RESUMO
STUDY QUESTION: What is the relationship between late follicular phase progesterone levels and clinic pregnancy and live birth rates in couples with unexplained infertility undergoing ovarian stimulation with IUI (OS-IUI)? SUMMARY ANSWER: Late follicular progesterone levels between 1.0 and <1.5 ng/ml were associated with higher live birth and clinical pregnancy rates while the outcomes in groups with higher progesterone levels did not differ appreciably from the <1.0 ng/ml reference group. WHAT IS KNOWN ALREADY: Elevated late follicular progesterone levels have been associated with lower live birth rates after fresh embryo transfer following controlled ovarian stimulation and egg retrieval, but less is known about whether an association exists with outcomes in OS-IUI cycles. Existing studies are few and have been limited to ovarian stimulation with gonadotrophins, but the use of oral agents, such as clomiphene citrate and letrozole, is common with these treatments and has not been well studied. STUDY DESIGN, SIZE, DURATION: The study was a prospective cohort analysis of the Assessment of Multiple Intrauterine Gestations from Ovarian Stimulation (AMIGOS) randomized controlled trial. Frozen serum was available for evaluation from 2121 cycles in 828 AMIGOS participants. The primary pregnancy outcome was live birth per cycle, and the secondary pregnancy outcome was clinical pregnancy rate per cycle. PARTICIPANTS/MATERIALS, SETTING, METHODS: Couples with unexplained infertility in the AMIGOS trial, for whom female serum from day of trigger with hCG was available in at least one cycle of treatment, were included. Stored frozen serum samples from day of hCG trigger during treatment with OS-IUI were evaluated for serum progesterone level. Progesterone level <1.0 ng/ml was the reference group for comparison with progesterone categorized in increments of 0.5 ng/ml up to ≥3.0 ng/ml. Unadjusted and adjusted risk ratios (RR) and 95% CI were estimated using cluster-weighted generalized estimating equations to estimate modified Poisson regression models with robust standard errors. MAIN RESULTS AND THE ROLE OF CHANCE: Compared to the reference group with 110/1363 live births (8.07%), live birth rates were significantly increased in cycles with progesterone 1.0 to <1.5 ng/ml (49/401 live births, 12.22%) in both the unadjusted (RR 1.56, 95% CI 1.14, 2.13) and treatment-adjusted models (RR 1.51, 95% CI 1.10, 2.06). Clinical pregnancy rates were also higher in this group (55/401 clinical pregnancies, 13.72%) compared to reference group with 130/1363 (9.54%) (unadjusted RR 1.46, 95% CI 1.10, 1.94 and adjusted RR 1.42, 95% CI 1.07, 1.89). In cycles with progesterone 1.5 ng/ml and above, there was no evidence of a difference in clinical pregnancy or live birth rates relative to the reference group. This pattern remained when stratified by ovarian stimulation treatment group but was only statistically significant in letrozole cycles. LIMITATIONS, REASONS FOR CAUTION: The AMIGOS trial was not designed to answer this clinical question, and with small numbers in some progesterone categories our analyses were underpowered to detect differences between some groups. Inclusion of cycles with progesterone values above 3.0 ng/ml may have included those wherein ovulation had already occurred at the time the IUI was performed. These cycles would be expected to experience a lower success rate but pregnancy may have occurred with intercourse in the same cycle. WIDER IMPLICATIONS OF THE FINDINGS: Compared to previous literature focusing primarily on OS-IUI cycles using gonadotrophins, these data include patients using oral agents and therefore may be generalizable to the wider population of infertility patients undergoing IUI treatments. Because live births were significantly higher when progesterone ranged from 1.0 to <1.5 ng/ml, further study is needed to clarify whether this progesterone range may truly represent a prognostic indicator in OS-IUI cycles. STUDY FUNDING/COMPETING INTEREST(S): Oklahoma Shared Clinical and Translational Resources (U54GM104938) National Institute of General Medical Sciences (NIGMS). AMIGOS was funded by the Eunice Kennedy Shriver National Institute of Child Health and Human Development: U10 HD077680, U10 HD39005, U10 HD38992, U10 HD27049, U10 HD38998, U10 HD055942, HD055944, U10 HD055936, and U10HD055925. Research made possible by the funding by American Recovery and Reinvestment Act. Dr Burks has disclosed that she is a member of the Board of Directors of the Pacific Coast Reproductive Society. Dr Hansen has disclosed that he is the recipient of NIH grants unrelated to the present work, and contracts with Ferring International Pharmascience Center US and with May Health unrelated to the present work, as well as consulting fees with May Health also unrelated to the present work. Dr Diamond has disclosed that he is a stockholder and a member of the Board of Directors of Advanced Reproductive Care, Inc., and that he has a patent pending for the administration of progesterone to trigger ovulation. Dr Anderson, Dr Gavrizi, and Dr Peck do not have conflicts of interest to disclose. TRIAL REGISTRATION NUMBER: N/A.
Assuntos
Inseminação Artificial , Indução da Ovulação , Resultado da Gravidez , Progesterona , Humanos , Feminino , Gravidez , Indução da Ovulação/métodos , Progesterona/sangue , Inseminação Artificial/métodos , Adulto , Taxa de Gravidez , Nascido Vivo , Estudos Prospectivos , Fase Folicular , Infertilidade/terapia , Infertilidade/sangue , Coeficiente de Natalidade , MasculinoRESUMO
OBJECTIVES: To identify uterine measurements that are reliable and accurate to distinguish between T-shaped and normal/arcuate uterus, and define T-shaped uterus, using Congenital Uterine Malformation by Experts (CUME) methodology, which uses as reference standard the decision made most often by several independent experts. METHODS: This was a prospectively planned multirater reliability/agreement and diagnostic accuracy study, performed between November 2017 and December 2018, using a sample of 100 three-dimensional (3D) datasets of different uteri with lateral uterine cavity indentations, acquired from consecutive women between 2014 and 2016. Fifteen representative experts (five clinicians, five surgeons and five sonologists), blinded to each others' opinions, examined anonymized images of the coronal plane of each uterus and provided their independent opinion as to whether it was T-shaped or normal/arcuate; this formed the basis of the CUME reference standard, with the decision made most often (i.e. that chosen by eight or more of the 15 experts) for each uterus being considered the correct diagnosis for that uterus. Two other experienced observers, also blinded to the opinions of the other experts, then performed independently 15 sonographic measurements, using the original 3D datasets of each uterus. Agreement between the diagnoses made by the 15 experts was assessed using kappa and percent agreement. The interobserver reliability of measurements was assessed using the concordance correlation coefficient (CCC). The diagnostic test accuracy was assessed using the area under the receiver-operating-characteristics curve (AUC) and the best cut-off value was assessed by calculating Youden's index, according to the CUME reference standard. Sensitivity, specificity, negative and positive likelihood ratios (LR- and LR+) and post-test probability were calculated. RESULTS: According to the CUME reference standard, there were 20 T-shaped and 80 normal/arcuate uteri. Individual experts recognized between 5 and 35 (median, 19) T-shaped uteri on subjective judgment. The agreement among experts was 82% (kappa = 0.43). Three of the 15 sonographic measurements were identified as having good diagnostic test accuracy, according to the CUME reference standard: lateral indentation angle (AUC = 0.95), lateral internal indentation depth (AUC = 0.92) and T-angle (AUC = 0.87). Of these, T-angle had the best interobserver reproducibility (CCC = 0.87 vs 0.82 vs 0.62 for T-angle vs lateral indentation depth vs lateral indentation angle). The best cut-off values for these measurements were: lateral indentation angle ≤ 130° (sensitivity, 80%; specificity, 96%; LR+, 21.3; LR-, 0.21), lateral indentation depth ≥ 7 mm (sensitivity, 95%; specificity, 77.5%; LR+, 4.2; LR-, 0.06) and T-angle ≤ 40° (sensitivity, 80%; specificity, 87.5%; LR+, 6.4; LR-, 0.23). Most of the experts diagnosed the uterus as being T-shaped in 0% (0/56) of cases when none of these three criteria was met, in 10% (2/20) of cases when only one criterion was met, in 50% (5/10) of cases when two of the three criteria were met, and in 93% (13/14) of cases when all three criteria were met. CONCLUSIONS: The diagnosis of T-shaped uterus is not easy; the agreement among experts was only moderate and the judgement of individual experts was commonly insufficient for accurate diagnosis. The three sonographic measurements with cut-offs that we identified (lateral internal indentation depth ≥ 7 mm, lateral indentation angle ≤ 130° and T-angle ≤ 40°) had good diagnostic test accuracy and fair-to-moderate reliability and, when applied in combination, they provided high post-test probability for T-shaped uterus. In the absence of other anomalies, we suggest considering a uterus to be normal when none or only one criterion is met, borderline when two criteria are met, and T-shaped when all three criteria are met. These three CUME criteria for defining T-shaped uterus may aid in determination of its prevalence, clinical implications and best management and in the assessment of post-surgical morphologic outcome. The CUME definition of T-shaped uterus may help in the development of interventional randomized controlled trials and observational studies and in the diagnosis of uterine morphology in everyday practice, and could be adopted by guidelines on uterine anomalies to enrich their classification systems. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.
Assuntos
Ultrassonografia/estatística & dados numéricos , Anormalidades Urogenitais/diagnóstico por imagem , Útero/anormalidades , Adulto , Área Sob a Curva , Feminino , Humanos , Funções Verossimilhança , Variações Dependentes do Observador , Gravidez , Estudos Prospectivos , Padrões de Referência , Reprodutibilidade dos Testes , Projetos de Pesquisa , Sensibilidade e Especificidade , Ultrassonografia/normas , Útero/diagnóstico por imagemRESUMO
STUDY QUESTION: Can asoprisnil, a selective progesterone receptor modulator, provide clinically meaningful improvements in heavy menstrual bleeding (HMB) associated with uterine fibroids with an acceptable safety profile? SUMMARY ANSWER: Uninterrupted treatment with asoprisnil for 12 months effectively controlled HMB and reduced fibroid and uterine volume with few adverse events. WHAT IS KNOWN ALREADY: In a 3-month study, asoprisnil (5, 10 and 25 mg) suppressed uterine bleeding, reduced fibroid and uterine volume, and improved hematological parameters in a dose-dependent manner. STUDY DESIGN, SIZE, DURATION: In two Phase 3, double-blind, randomized, placebo-controlled, multicentre studies, women received oral asoprisnil 10 mg, asoprisnil 25 mg or placebo (2:2:1) once daily for up to 12 months. PARTICIPANTS/MATERIALS, SETTING, METHODS: Premenopausal women ≥18 years of age in North America with HMB associated with uterine fibroids were included (N = 907). The primary efficacy endpoint was the percentage of women who met all three predefined criteria at 12 months or the final month for patients who prematurely discontinued: (1) ≥50% reduction in monthly blood loss (MBL) by menstrual pictogram, (2) hemoglobin concentration ≥11 g/dL or an increase of ≥1 g/dL, and (3) no interventional therapy for uterine fibroids. Secondary efficacy endpoints included changes in other menstrual bleeding parameters, volume of the largest fibroids, uterine volume and health-related quality of life (HRQL). MAIN RESULTS AND THE ROLE OF CHANCE: In all, 90% and 93% of women in the asoprisnil 10-mg and 25-mg groups, respectively, and 35% of women in the placebo group met the primary endpoint (P < 0.001). Similar results were observed at month 6 (P < 0.001). The percentage of women who achieved amenorrhea in any specified month ranged from 66-78% in the asoprisnil 10-mg group and 83-93% in the asoprisnil 25-mg group, significantly higher than with placebo (3-12%, P < 0.001). Hemoglobin increased rapidly (by month 2) with asoprisnil treatment and was significantly higher versus placebo throughout treatment. The primary fibroid and uterine volumes were significantly reduced from baseline through month 12 with asoprisnil 10 mg (median changes up to -48% and -28%, respectively) and 25 mg (median changes up to -63% and -39%, respectively) versus placebo (median changes up to +16% and +13%, respectively; all P < 0.001). Dose-dependent, significant improvements in HRQL (Uterine Fibroid Symptom and Quality of Life instrument) were observed with asoprisnil treatment. Asoprisnil was generally well tolerated. Endometrial biopsies indicated dose- and time-dependent decreases in proliferative patterns and increases in quiescent or minimally stimulated endometrium at month 12 of treatment. Although not statistically significantly different at month 6, mean endometrial thickness at month 12 increased by ~2 mm in both asoprisnil groups compared with placebo (P < 0.01). This effect was associated with cystic changes in the endometrium on MRI and ultrasonography, which led to invasive diagnostic and therapeutic procedures in some asoprisnil-treated women. LIMITATIONS, REASONS FOR CAUTION: Most study participants were black; few Asian and Hispanic women participated. The study duration may have been insufficient to fully characterize the endometrial effects. WIDER IMPLICATIONS OF THE FINDINGS: Daily uninterrupted treatment with asoprisnil was highly effective in controlling menstrual bleeding, improving anemia, reducing fibroid and uterine volume, and increasing HRQL in women with HMB associated with uterine fibroids. However, this treatment led to an increase in endometrial thickness and invasive diagnostic and therapeutic procedures, with potential unknown consequences. STUDY FUNDING/COMPETING INTEREST(S): This trial was funded by AbbVie Inc. (prior sponsors: TAP Pharmaceutical Products Inc., Abbott Laboratories). E.A. Stewart was a site investigator in the Phase 2 study of asoprisnil and consulted for TAP during the design and conduct of these studies while at Harvard Medical School and Brigham and Women's Hospital. She received support from National Institutes of Health grants HD063312, HS023418 and HD074711 and research funding, paid to Mayo Clinic for patient care costs related to an NIH-funded trial from InSightec Ltd. She consulted for AbbVie, Allergan, Bayer HealthCare AG, Gynesonics, and Welltwigs. She received royalties from UpToDate and the Med Learning Group. M.P. Diamond received research funding for the conduct of the studies paid to the institution and consulted for AbbVie. He is a stockholder and board and director member of Advanced Reproductive Care. He has also received funding for study conduct paid to the institution from Bayer and ObsEva. A.R.W. Williams consulted for TAP and Repros Therapeutics Inc. He has current consultancies with PregLem SA, Gedeon Richter, HRA Pharma and Bayer. B.R. Carr consulted for and received research funding from AbbVie. E.R. Myers consulted for AbbVie, Allergan and Bayer. R.A. Feldman received compensation for serving as a principal investigator and participating in the conduct of the trial. W. Elger was co-inventor of several patents related to asoprisnil. C. Mattia-Goldberg is a former employee of AbbVie and may own AbbVie stock or stock options. B.M. Schwefel and K. Chwalisz are employees of AbbVie and may own AbbVie stock or stock options. TRIAL REGISTRATION NUMBER: NCT00152269, NCT00160381 (clinicaltrials.gov). TRIAL REGISTRATION DATE: 7 September 2005; 8 September 2005. DATE OF FIRST PATIENT'S ENROLMENT: 12 September 2002; 6 September 2002.
Assuntos
Estrenos/efeitos adversos , Estrenos/uso terapêutico , Leiomioma/tratamento farmacológico , Menorragia/tratamento farmacológico , Oximas/efeitos adversos , Oximas/uso terapêutico , Receptores de Progesterona/efeitos dos fármacos , Neoplasias Uterinas/tratamento farmacológico , Administração Oral , Adulto , Método Duplo-Cego , Endométrio/efeitos dos fármacos , Estrenos/administração & dosagem , Feminino , Seguimentos , Humanos , Leiomioma/complicações , Menorragia/complicações , Pessoa de Meia-Idade , Oximas/administração & dosagem , Medidas de Resultados Relatados pelo Paciente , Pré-Menopausa , Qualidade de Vida , Resultado do Tratamento , Carga Tumoral/efeitos dos fármacos , Neoplasias Uterinas/complicaçõesRESUMO
Postoperative abdominal/pelvic peritoneal adhesions are a major source of morbidity (bowel obstruction, infertility, ectopic gestation as well as chronic pelvic pain) in women. In this study, we screened various transduction and transcription modifications of adenovirus (Ad) to identify those that support maximal Ad-mediated gene delivery to human adhesion fibroblasts, which in turn would enhance the efficacy of this novel treatment/preventative strategy for postoperative adhesions. We transduced primary cultures of human peritoneal adhesion fibroblasts with fiber-modified Ad vectors Ad5-RGD-luc, Ad5-Sigma-luc, Ad5/3-luc and Ad5-CAV2-luc as well as transcriptional targeting viruses Ad5-survivin-luc, Ad5-heparanase-luc, Ad5-mesothelin (MSLN)-CRAd-luc and Ad5-secretory leukoprotease inhibitor (SLPI)-luc, and compared their activity to wild-type Ad5-luc. At 48 h, luciferase activity was measured and normalized to the total protein content in the cells. Among the fiber-modified Ad vectors, Ad5-Sigma-luc and among the transcriptional targeting modified Ad vectors, Ad5-MSLN-CRAd-luc showed significantly increased expression levels of luciferase activity at 5, 10 and 50 plaque forming units/cell in adhesion fibroblast cells compared with wild-type Ad5-luc (p < 0.05). Specific modifications of Ad improve their gene delivery efficiency towards human peritoneal adhesion fibroblasts. Developing a safe localized method to prevent/treat postoperative adhesion formation would have a major impact on women health.
Assuntos
Adenoviridae/genética , Fibroblastos , Terapia Genética , Aderências Teciduais/terapia , Transdução Genética , Células Cultivadas , Fibroblastos/enzimologia , Expressão Gênica , Vetores Genéticos , Humanos , Luciferases/genética , Luciferases/metabolismo , Mesotelina , Aderências Teciduais/prevenção & controle , Transcrição GênicaRESUMO
PURPOSE: Fibroids are the most common smooth muscle overgrowth in women. This study determined the expression and the effect of hypoxia on two potent antioxidant enzymes, superoxide dismutase (SOD) and catalase (CAT) on human fibroid cells. METHODS: Immortalized human leiomyoma (fibroid) and myometrial cells were subjected to hypoxia (2 % O2, 24 h). Total RNA and cell homogenate were obtained from control and treated cells; CAT and SOD mRNA and activity levels were determined by real-time RT-PCR and ELISA, respectively. RESULTS: Fibroid cells have significantly lower antioxidant enzymes, SOD and CAT mRNA and activity levels than normal myometrial cells (p < 0.05). Hypoxia treatment significantly increased SOD activity in myometrial cells while significantly decreasing CAT activity in fibroid cells (p < 0.05). There was no significant difference in CAT mRNA levels or activity in response to hypoxia in myometrial cells. Also, there was no significant difference in SOD mRNA levels in response to hypoxia in myometrial cells. CONCLUSION: This is the first report to show that uterine fibroids are characterized by an impaired antioxidant cellular enzymatic system. More importantly, our results indicate a role for hypoxia in the modulation of the balance of those enzymes in fibroid and myometrial cells. Collectively, these results shed light on the pathophysiology of fibroids thereby providing potential targets for novel fibroid treatment.
Assuntos
Catalase/biossíntese , Leiomioma/metabolismo , Superóxido Dismutase/biossíntese , Neoplasias Uterinas/metabolismo , Catalase/genética , Catalase/metabolismo , Hipóxia Celular , Células Cultivadas , Feminino , Humanos , Oxirredução , RNA Mensageiro/análise , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismoRESUMO
BACKGROUND: Intrauterine insemination with ovarian stimulation (IUI-OS) is a first-line treatment for unexplained infertility. Gonadotrophins, letrozole and clomiphene citrate (CC) are commonly used agents during IUI-OS and have been compared in multiple aggregate data meta-analyses, with substantial heterogeneity and no analysis on time-to-event outcomes. Individual participant data meta-analysis (IPD-MA) is considered the gold standard for evidence synthesis as it can offset inadequate reporting of individual studies by obtaining the IPD, and allows analyses on treatment-covariate interactions to identify couples who benefit most from a particular treatment. OBJECTIVE AND RATIONALE: We performed this IPD-MA to compare the effectiveness and safety of ovarian stimulation with gonadotrophins, letrozole and CC and to explore treatment-covariate interactions for important baseline characteristics in couples undergoing IUI. SEARCH METHODS: We searched electronic databases including MEDLINE, EMBASE, CENTRAL, CINAHL, and PsycINFO from their inception to 28 June 2021. We included randomized controlled trials (RCTs) comparing IUI-OS with gonadotrophins, letrozole and CC among couples with unexplained infertility. We contacted the authors of eligible RCTs to share the IPD and established the IUI IPD-MA Collaboration. The primary effectiveness outcome was live birth and the primary safety outcome was multiple pregnancy. Secondary outcomes were other reproductive outcomes, including time to conception leading to live birth. We performed a one-stage random effects IPD-MA. OUTCOMES: Seven of 22 (31.8%) eligible RCTs provided IPD of 2495 couples (62.4% of the 3997 couples participating in 22 RCTs), of which 2411 had unexplained infertility and were included in this IPD-MA. Six RCTs (n = 1511) compared gonadotrophins with CC, and one (n = 900) compared gonadotrophins, letrozole and CC. Moderate-certainty evidence showed that gonadotrophins increased the live birth rate compared to CC (6 RCTs, 2058 women, RR 1.30, 95% CI 1.12-1.51, I2 = 26%). Low-certainty evidence showed that gonadotrophins may also increase the multiple pregnancy rate compared to CC (6 RCTs, 2058 women, RR 2.17, 95% CI 1.33-3.54, I2 = 69%). Heterogeneity on multiple pregnancy could be explained by differences in gonadotrophin starting dose and choice of cancellation criteria. Post-hoc sensitivity analysis on RCTs with a low starting dose of gonadotrophins (≤75 IU) confirmed increased live birth rates compared to CC (5 RCTs, 1457 women, RR 1.26, 95% CI 1.05-1.51), but analysis on only RCTs with stricter cancellation criteria showed inconclusive evidence on live birth (4 RCTs, 1238 women, RR 1.15, 95% CI 0.94-1.41). For multiple pregnancy, both sensitivity analyses showed inconclusive findings between gonadotrophins and CC (RR 0.94, 95% CI 0.45-1.96; RR 0.81, 95% CI 0.32-2.03, respectively). Moderate certainty evidence showed that gonadotrophins reduced the time to conception leading to a live birth when compared to CC (6 RCTs, 2058 women, HR 1.37, 95% CI 1.15-1.63, I2 = 22%). No strong evidence on the treatment-covariate (female age, BMI or primary versus secondary infertility) interactions was found. WIDER IMPLICATIONS: In couples with unexplained infertility undergoing IUI-OS, gonadotrophins increased the chance of a live birth and reduced the time to conception compared to CC, at the cost of a higher multiple pregnancy rate, when not differentiating strategies on cancellation criteria or the starting dose. The treatment effects did not seem to differ in women of different age, BMI or primary versus secondary infertility. In a modern practice where a lower starting dose and stricter cancellation criteria are in place, effectiveness and safety of different agents seem both acceptable, and therefore intervention availability, cost and patients' preferences should factor in the clinical decision-making. As the evidence for comparisons to letrozole is based on one RCT providing IPD, further RCTs comparing letrozole and other interventions for unexplained infertility are needed.
Assuntos
Infertilidade Feminina , Infertilidade , Clomifeno/uso terapêutico , Feminino , Fármacos para a Fertilidade Feminina/uso terapêutico , Gonadotropinas/uso terapêutico , Humanos , Infertilidade/terapia , Infertilidade Feminina/terapia , Inseminação , Letrozol/uso terapêutico , Nascido Vivo , Indução da Ovulação , Gravidez , Taxa de GravidezRESUMO
Intact ribosomal RNAs (rRNAs) comprise the majority of somatic transcripts, yet appear conspicuously absent in spermatozoa, perhaps reflecting cytoplasmic expulsion during spermatogenesis. To discern their fate, total RNA retained in mature spermatozoa from three fertile donors was characterized by Next Generation Sequencing. In all samples, >75% of total sequence reads aligned to rRNAs. The distribution of reads along the length of these transcripts exhibited a high degree of non-uniformity that was reiterated between donors. The coverage of sequencing reads was inversely correlated with guanine-cytosine (GC)-richness such that sequences greater than â¼70% GC were virtually absent in all sperm RNA samples. To confirm the loss of sequence, the relative abundance of specific regions of the 28S transcripts in sperm was established by 7-Deaza-2'-deoxy-guanosine-5'-triphosphate RT-PCR. The inability to amplify specific regions of the 28S sequence from sperm despite the abundant representation of this transcript in the sequencing libraries demonstrates that approximately three-quarters of RNA retained in the mature male gamete are products of rRNA fragmentation. Hence, cleavage (not expulsion of the RNA component of the translational machinery) is responsible for preventing spurious translation following spermiogenesis. These results highlight the potential importance of those transcripts, including many mRNAs, which evade fragmentation and remain intact when sperm are delivered at fertilization. Sequencing data are deposited in GEO as: GSE29160.
Assuntos
Sequenciamento de Nucleotídeos em Larga Escala/métodos , Biossíntese de Proteínas/fisiologia , Clivagem do RNA/fisiologia , RNA Ribossômico 28S/metabolismo , RNA Ribossômico/metabolismo , Espermatogênese/genética , Espermatozoides/metabolismo , Composição de Bases , Fertilidade/genética , Fertilização/genética , Humanos , Masculino , RNA Ribossômico/genética , RNA Ribossômico 28S/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Testículo/metabolismoRESUMO
STUDY QUESTION: What is the safety and efficacy profile during long-term (12-24 months) uninterrupted treatment with the selective progesterone receptor modulator asoprisnil, 10 and 25 mg in women with heavy menstrual bleeding (HMB) associated with uterine fibroids? SUMMARY ANSWER: Uninterrupted treatment with asoprisnil should be avoided due to endometrial safety concerns and unknown potential long-term consequences. WHAT IS KNOWN ALREADY: Asoprisnil was well tolerated in shorter-term studies and effectively suppressed HMB and reduced fibroid volume. STUDY DESIGN SIZE DURATION: Women with uterine fibroids who had previously received placebo (n = 87) or asoprisnil 10 mg (n = 221) or 25 mg (n = 215) for 12 months in two double-blind studies entered this randomized uncontrolled extension study and received up to 12 additional months of treatment followed by 6 months of post-treatment follow-up. Women who previously received placebo were re-randomized to either asoprisnil 10 or 25 mg for the extension study. This report focuses on the 436 women who received asoprisnil in the double-blind studies and this extension study. Results for women who previously received placebo in the double-blind studies are not described. PARTICIPANTS/MATERIALS SETTING METHODS: Women ≥18 years of age who completed a 12-month, double-blind, placebo-controlled study, had estradiol levels indicating that they were not menopausal and had no endometrial hyperplasia or other significant endometrial pathology were eligible. The safety endpoints were focused on endometrial assessments. The composite primary efficacy endpoint was the proportion of women who demonstrated a response to treatment by meeting all three of the following criteria at the final month for participants who prematurely discontinued or at month 12 for those who completed the study: a reduction from initial baseline to final visit of ≥50% in the menstrual pictogram score, hemoglobin concentration ≥11 g/dl or an increase of ≥1 g/dl from initial baseline at the final visit, and no surgical or invasive intervention for uterine fibroids. Other efficacy endpoints included rates for amenorrhea and suppression of bleeding, changes in fibroid and uterine volume and changes in hematologic parameters. No statistical tests were planned or performed for this uncontrolled study. MAIN RESULTS AND ROLE OF CHANCE: Imaging studies revealed a progressive increase in endometrial thickness and cystic changes that frequently prompted invasive diagnostic procedures. Endometrial biopsy results were consistent with antiproliferative effects of asoprisnil. Two cases of endometrial cancer were diagnosed. At the final month of this extension study (total duration of uninterrupted treatment up to 24 months), the primary efficacy endpoint was achieved in 86 and 92% of women in the asoprisnil 10- and 25-mg groups, respectively. During each month of treatment, amenorrhea was observed in the majority of women (up to 77 and 94% at 10 and 25 mg, respectively). There was a progressive, dose-dependent decrease in the volume of the primary fibroid with asoprisnil 10 and 25 mg (-55.7 and -75.2% median decrease, respectively, from baseline [i.e. the beginning of the placebo-controlled study] to month 12 [cumulative months 12-24] of this extension study). These effects were associated with improvements in quality of life measures. LIMITATIONS REASONS FOR CAUTION: This study was uncontrolled, which limits the interpretation of safety and efficacy findings. The study also had multiple protocol amendments with the addition of diagnostic procedures and, because no active comparator was included, the potential place of asoprisnil in comparison to therapies such as GnRH agonists and surgery cannot be determined. WIDER IMPLICATIONS OF THE FINDINGS: Long-term, uninterrupted treatment with asoprisnil leads to prominent cystic endometrial changes that are consistent with the 'late progesterone receptor modulator' effects, which prompted invasive diagnostic procedures, although treatment efficacy is maintained. Although endometrial cancers were uncommon during both treatment and follow-up, these findings raise concerns regarding endometrial safety during uninterrupted long-term treatment with asoprisnil. This study shows that uninterrupted treatment with asoprisnil should be avoided due to safety concerns and unknown potential long-term consequences. STUDY FUNDING/COMPETING INTERESTS: AbbVie Inc. (prior sponsor, TAP Pharmaceutical Products Inc.) sponsored the study and contributed to the design and conduct of the study, data management, data analysis, interpretation of the data and the preparation and approval of the manuscript. Financial support for medical writing and editorial assistance was provided by AbbVie Inc. M. P. Diamond received research funding for the conduct of the study paid to the institution and is a consultant to AbbVie. He is a stockholder and board and director member of Advanced Reproductive Care. He has also received funding for study conduct paid to the institution for Bayer and ObsEva. E. A. Stewart participated as a site investigator in the phase 2 study of asoprisnil and served as a consultant to TAP Pharmaceuticals during the time of design and conduct of the studies while on the faculty of Harvard Medical School and Brigham and Women's Hospital, Boston, MA. In the last 3 years, she has received support from National Institutes of Health grants HD063312, HS023418 and HD074711. She has served as a consultant for AbbVie Inc., Allergan, Bayer HealthCare AG and Myovant for consulting related to uterine leiomyoma and to Welltwigs for consulting related to infertility. She has received royalties from UpToDate and the Med Learning Group. A.R.W. Williams has acted as a consultant for TAP Pharmaceutical Products Inc. and Repros Therapeutics Inc. He has current consultancies with PregLem SA, Gedeon Richter, HRA Pharma and Bayer. B.R. Carr has served as consultant and received research funding from AbbVie Inc. and Synteract (Medicines360). E.R. Myers has served as consultant for AbbVie Inc., Allergan and Bayer. R.A. Feldman received compensation for serving as a principal investigator and participating in the conduct of the trial. W. Elger was a co-inventor of several patents related to asoprisnil.C. Mattia-Goldberg is a former employee of AbbVie Inc. and owns AbbVie stock or stock options. B.M. Schwefel and K. Chwalisz are employees of AbbVie Inc. and own AbbVie stock or stock options. TRIAL REGISTRATION NUMBER: NCT00156195 at clinicaltrials.gov.
RESUMO
Uterine artery embolization (UAE) is typically not indicated in the pre-operative management of pregnancies with a live fetus, because risk of fetal death from reduced uteroplacental blood flow. However, pre-operative UAE in pregnancies with a fetal demise poses no fetal risk, and may offer maternal benefits. Patients with placental abruption resulting in fetal demise are at high-risk for developing disseminated intravascular coagulation (DIC), which could have devastating complications such as peri-operative hemorrhage and death. This case report describes the first successful execution of a pre-operative UAE that effectively prevented antepartum and postpartum hemorrhage in a patient with DIC secondary to a placental abruption and recent fetal demise.
Assuntos
Descolamento Prematuro da Placenta/diagnóstico por imagem , Transfusão de Sangue/métodos , Coagulação Intravascular Disseminada/diagnóstico por imagem , Morte Fetal , Complicações na Gravidez/diagnóstico por imagem , Embolização da Artéria Uterina , Dor Abdominal , Descolamento Prematuro da Placenta/terapia , Adulto , Coagulação Intravascular Disseminada/complicações , Coagulação Intravascular Disseminada/terapia , Feminino , Humanos , Gravidez , Complicações na Gravidez/terapia , Resultado do Tratamento , Embolização da Artéria Uterina/métodosRESUMO
We previously showed that infusion of glucagon at four times the basal rate into conscious dogs given somatostatin and basal replacement amounts of insulin caused hyperglycemia (217 15 mg/dl) for at least 3 h and an initial increment in hepatic glucose production of 5.5 0.8 mg/kg . min. After 3 h, however, the effect of hyperglucagonemia on glucose production had declined by 85%. The aim of the present study was to determine the importance of hyperglycemia in the "downregulation" of the action of glucagon. Six overnight-fasted conscious dogs were given somatostatin (0.8 microgram/kg . min) plus basal intraportal replacement amounts of insulin (263 microunits/kg . min) and glucagon (0.65 ng/kg . min). Hyperglycemia (276 12 md/dl) was established after 2 h by the infusion of exogenous glucose. The glucagon infusion rate was then increased fourfold 1 h later, so that the plasma glucagon level rose from 95 16 to 227 35 pg/ml. The glucose concentration was maintained at a fixed value despite the increase in glucagon by decreasing the glucose infusion rate by an amount equal to the increase in endogenous glucose production induced by the hormone. Glucose production was measured using a primed infusion of 3H-glucose. With the insulin (11 2 microunits/ml) and glucose levels fixed, the elevation in glucagon caused an initial increment of 5.1 0.7 mg/kg . min in glucose production which was followed by a fall of only 2.5 0.4 mg/kg . min (50%) over the next 3 hr. Thus, when the plasma glucagon level is raised fourfold under conditions in which insulin mobilization cannot occur, the effect of hyperglucagonemia on glucose production will be partially offset by the resulting hyperglycemia and partly inhibited by an hepatic factor(s).
Assuntos
Glucagon/fisiologia , Glucose/biossíntese , Animais , Cães , Feminino , Glucagon/sangue , Insulina/metabolismo , Secreção de Insulina , Fígado/fisiologia , MasculinoRESUMO
Intensive insulin treatment during diabetic pregnancy is complicated by maternal hypoglycemia. To investigate whether pregnancy may contribute as an independent hypoglycemia risk factor, awake pregnant rats that were near term underwent stepped insulin hypoglycemic (3.4 and 2.3 mM) clamp studies in the fasted and nonfasted states. In the fasted state, the glucagon response to hypoglycemia was completely suppressed in the pregnant rats (P < 0.01). Epinephrine, but not norepinephrine, was also diminished by approximately 70-75% at both hypoglycemic steps, and more exogenous glucose was needed to maintain hypoglycemia during pregnancy. To avoid the potential confounding effect of increased ketone levels (beta-hydroxybutyrate was approximately 170% higher in the pregnant rats), experiments were repeated in the nonfasting state when ketosis was eliminated in both groups. The nonfasted pregnant rats continued to show near complete suppression of the glucagon response, even at glucose levels of 2.3 mM. In contrast, a brisk response occurred in nonpregnant controls when glucose fell to 3.4 mM. Although epinephrine levels in the pregnant rats were also markedly suppressed during the milder hypoglycemic stimulus, they approached values seen in nonpregnant controls when glucose was lowered further to 2.3 mM. We concluded that in the rat, pregnancy markedly suppresses glucagon responses to hypoglycemia. The release of epinephrine, but not norepinephrine, is also blunted, especially during mild hypoglycemia. These findings suggest that pregnancy may impair glucose counterregulation by inhibiting glucagon and epinephrine release during hypoglycemia.
Assuntos
Epinefrina/sangue , Glucagon/sangue , Hipoglicemia/sangue , Hipoglicemia/fisiopatologia , Gravidez em Diabéticas/fisiopatologia , Ácido 3-Hidroxibutírico , Análise de Variância , Animais , Glicemia/análise , Jejum , Feminino , Hidroxibutiratos/sangue , Hipoglicemia/induzido quimicamente , Insulina/efeitos adversos , Resistência à Insulina/fisiologia , Gravidez , Gravidez em Diabéticas/sangue , Ratos , Ratos Sprague-DawleyRESUMO
The effects of sodium dichloroacetate (DCA) on carbohydrate metabolism in conscious, 48-h-fasted dogs were examined using the hepatic A-V difference technique and a double isotope infusion technique (3H-glucose to measure glucose production and 14C-alanine to assess gluconeogenesis). DCA infusion (0.4 mg/kg-min) resulted in an 82 +/- 1% fall in the arterial plasma alanine level and a 53 +/- 8% fall in the arterial whole blood lactate level. Hepatic uptake of alanine and lactate fell 67 +/- 5% and 59 +/- 15%, respectively, although the fractional extraction of these intermediates was not altered. DCA decreased the conversion of circulating alanine and lactate to glucose but by only 41 +/- 7%, suggesting that a slight increase in the efficiency of the intrahepatic gluconeogenic process took place. This may be explained by the decrease in the plasma insulin level (39 +/- 9%) that occurred in the presence of an unchanged plasma glucagon concentration. Despite the substantial fall in the levels of gluconeogenic precursors in blood and the considerable decrease in their rate of conversion to glucose, the overall rates of glucose production and the blood glucose concentration were not altered by DCA. These data indicate that the alanine and lactate supplied by the periphery after a 48 h fast in the dog are not essential for the acute maintenance of glucose production or euglycemia. They suggest, further, that a compensatory increase in glucose production can occur by drawing on an alternate intrahepatic carbon source, the nature of which and signal for which remain unclear.
Assuntos
Acetatos/farmacologia , Ácido Dicloroacético/farmacologia , Glucose/metabolismo , Alanina/metabolismo , Aminoácidos/sangue , Animais , Cães , Feminino , Glucagon/sangue , Gluconeogênese/efeitos dos fármacos , Glicerol/metabolismo , Insulina/sangue , Cinética , Fígado/metabolismo , MasculinoRESUMO
OBJECTIVE: To examine the hormonal mechanisms underlying the variability in glycemic control during the different phases of the menstrual cycle in women with insulin-dependent diabetes mellitus (IDDM). RESEARCH DESIGN AND METHODS: Hyperglycemic (11.7 +/- 0.1 mM), hyperinsulinemic (24 +/- 3 mU/L) clamp studies were performed in 16 women with IDDM during the follicular (day 8 +/- 1) and luteal (day 23 +/- 1) phases of the menstrual cycle. Seven of the patients (group 1) experienced worsening glucose control during the luteal phase, whereas nine patients (group 2) did not. RESULTS: In group 1, glucose metabolism fell from 30.2 +/- 3.8 mumol.kg-1.min-1 during the follicular phase to 24.5 +/- 2.0 mumol.kg-1.min-1 during the luteal phase (P = 0.09), whereas in group 2 it increased from 18.5 +/- 1.2 to 23.2 +/- 2.3 mumol.kg-1.min-1 (P = 0.03). The decrease in glucose metabolism during the luteal phase in patients in group 1 was associated with a significant rise in the serum estradiol levels from the follicular to luteal phase (164 +/- 39 vs. 352 +/- 59 pM, P = 0.006), whereas this rise was not observed in group 2 (334 +/- 156 vs. 423 +/- 74 pM, NS). Changes in other reproductive hormones (progesterone, testosterone, dihydrotestosterone, androstenedione, luteinizing hormone, follicular-stimulating hormone, or prolactin) were not related to the differences in glucose uptake in the two groups. CONCLUSIONS: 1) Marked heterogeneity in glucose metabolism is seen throughout the menstrual cycle in women with IDDM, 2) a subgroup of patients exhibits worsening premenstrual hyperglycemia and a decline in insulin sensitivity during the luteal phase, and 3) the deterioration in glucose uptake in this subgroup was associated with a greater increment in estradiol levels from the follicular to the luteal phase.
Assuntos
Glicemia/metabolismo , Diabetes Mellitus Tipo 1/fisiopatologia , Ciclo Menstrual/sangue , Adulto , Diabetes Mellitus Tipo 1/sangue , Feminino , Fase Folicular , Técnica Clamp de Glucose , Humanos , Hiperglicemia/fisiopatologia , Sistemas de Infusão de Insulina , Fase LutealRESUMO
OBJECTIVE: To examine whether pork and human insulin induce different counterregulatory responses to hypoglycemia. RESEARCH DESIGN AND METHODS: The responses to a mild hypoglycemic stimulus were determined in 35 healthy young adults with the glucose-clamp technique to ensure standardization of glucose and insulin levels. Either pork (n = 15) or human (n = 20) regular insulin was infused (0.8 mU.kg-1.min-1) to lower plasma glucose from 4.7 +/- 0.07 to 3.3 +/- 0.04 mM (both groups) over approximately 40 min. Plasma glucose was maintained at that level (with variable rate glucose infusion) for an additional 60 min. RESULTS: Steady-state insulin levels were similar in both groups (316 +/- 50 vs. 280 +/- 29 pM, pork vs. human). Before insulin administration, basal counterregulatory hormone levels were indistinguishable. Most importantly, after plasma glucose was lowered, hormonal responses were nearly identical. No significant differences in peak values of epinephrine (1769 +/- 404 vs. 1775 +/- 311 pM, pork vs. human), norepinephrine (1.64 +/- 0.23 vs. 1.87 +/- 0.20 nM, pork vs. human), glucagon (163 +/- 29 vs. 175 +/- 20 ng/L, pork vs. human), growth hormone (14 +/- 3 vs. 17 +/- 3 micrograms/L, pork vs. human), or cortisol (543 +/- 83 vs. 458 +/- 28 nM, pork vs. human) occurred. CONCLUSIONS: Our data suggest that pork and human insulin produce a comparable and robust hormonal response in healthy adults under conditions of controlled hypoglycemia.
Assuntos
Hormônios/sangue , Hipoglicemia/fisiopatologia , Insulina/farmacologia , Adulto , Animais , Epinefrina/sangue , Retroalimentação , Feminino , Glucagon/sangue , Técnica Clamp de Glucose , Hormônio do Crescimento/sangue , Hormônios/metabolismo , Humanos , Hidrocortisona/sangue , Infusões Intravenosas , Insulina/administração & dosagem , Masculino , Norepinefrina/sangue , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/farmacologia , Especificidade da Espécie , SuínosRESUMO
In mammals, insulin stimulates granulosa cell aromatase activity and steroid production and is a regulating factor of oocyte maturation. To assess the role of insulin in human follicular and oocyte maturation, human follicular fluid was obtained 32-36 h after hCG administration at the time of oocyte recovery for in vitro fertilization. Follicular fluid insulin levels, measured by RIA, ranged from undetectable (less than 2 microU/ml) to 65.4 microU/ml. In women treated with human menopausal gonadotropin (n = 21), clomiphene citrate (n = 4), and human menopausal gonadotropin/clomiphene citrate (n = 14), follicular fluid insulin concentrations were 18.0 +/- 4.3 (+/- SE), 10.2 +/- 4.2, and 12.0 +/- 3.8 microU/ml, respectively (P = NS). Similarly, there was no significant difference in follicular fluid insulin concentrations in follicles with mature (n = 33) or immature (n = 6) oocytes (13.3 +/- 2.7 vs. 24.7 +/- 9.5 microU/ml) or in oocytes which eventually did (n = 35) or did not (n = 4) fertilize (16.4 +/- 3.0 vs. 3.2 +/- 0.8 microU/ml). Follicular fluid insulin levels (n = 30) correlated positively with follicular fluid progesterone levels (P less than 0.05), but not with follicular fluid estradiol or androstenedione levels or the estradiol to androstenedione ratio. The relationship of follicular fluid insulin and progesterone levels suggests that, as in other mammals, follicular fluid insulin may have a physiological role in follicular maturation.
Assuntos
Insulina/metabolismo , Folículo Ovariano/metabolismo , Adulto , Androstenodiona/metabolismo , Líquidos Corporais/metabolismo , Estradiol/metabolismo , Feminino , Fertilização in vitro , Humanos , Insulina/sangue , Oócitos/crescimento & desenvolvimento , Progesterona/metabolismoRESUMO
Extreme pharmacological elevation of the circulating insulin level acutely lowers dehydroepiandrosterone sulfate (DHEAS) levels. To assess whether more physiological elevations in plasma insulin (due to exogenous infusion or endogenous secretion) would have similar effects, we examined the levels of DHEAS, androstenedione, testosterone, and free testosterone before and after euglycemic hyperinsulinemic and hyperglycemic hyperinsulinemic clamp studies. Studies were performed in women within 20% of ideal body weight after an overnight fast. Androgen levels were measured before and at the conclusion of studies in which either insulin was infused exogenously at 1 mU/kg.min or endogenous insulin secretion was stimulated for 2 h by elevation of the plasma glucose concentration by 125 mg/dL above basal levels by an exogenous glucose infusion. Basal plasma DHEAS (6.2 +/- 0.5 mumol/L) declined to 5.2 +/- 0.4 mumol/L (P less than 0.001) during the euglycemic insulin clamp, without any significant change in testosterone, free testosterone, or androstenedione. During the hyperglycemic clamp, DHEAS fell from 6.7 +/- 0.5 to 5.1 +/- 0.4 mumol/L (P less than 0.001) in response to endogenous hyperinsulinemia; plasma testosterone, free testosterone, and androstenedione did not change significantly. There was no correlation between the elevation in plasma insulin concentration and the fall in DHEAS during either the euglycemic or hyperglycemic clamps. However, the magnitude of fall of DHEAS was directly correlated with the initial DHEAS level in both the euglycemic (r = 0.51; P less than 0.05) and hyperglycemic (r = 0.75; P less than 0.01) studies. This association of hyperinsulinemia with a reduction of circulating levels of DHEAS, but not other C-19 steroids (e.g. testosterone and androstenedione) may reflect differential mechanisms by which DHEAS levels are regulated and suggests that insulin either inhibits its biosynthesis and/or secretion, or enhances its MCR.
Assuntos
Androgênios/sangue , Insulina/sangue , Androstenodiona/sangue , Desidroepiandrosterona/análogos & derivados , Desidroepiandrosterona/sangue , Sulfato de Desidroepiandrosterona , Feminino , Técnica Clamp de Glucose , Humanos , Insulina/metabolismo , Insulina/farmacologia , Secreção de Insulina , Concentração Osmolar , Valores de Referência , Testosterona/sangueRESUMO
The frequent coexistence of hyperandrogenism and insulin resistance is well established; however, whether a cause and effect relationship exists remains to be established. In this study we tested the hypothesis that short-term androgen administered to women would induce insulin resistance. To test this hypothesis, regularly menstruating, nonobese women were studied before and during methyltestosterone administration (5 mg tid for 10-12 days) by the hyperglycemic (n=8) and euglycemic, hyperinsulinemic (n=7) clamp techniques. Short-term methyltestosterone administration had no significant effects on the fasting levels of glucose, insulin, c-peptide, glucagon, or glucose turnover. During the hyperglycemic clamp studies, the mean glucose level during the final hour was 203+/-2 and 201+/-1 mg/dL in the methyltestosterone and control studies, respectively. The insulin response to this hyperglycemic challenge was slightly but not significantly greater during methyltestosterone treatment (first phase 59+/-8 vs. 50+/-8 microU/mL in controls; second phase 74+/-9 vs. 67+/-9 microU/mL in controls; total insulin response 133+/-16 vs. 117+/-15 microU/mL in controls). In spite of this, glucose uptake was reduced from the control study value of 10.96+/-1.11 to 7.3+/-0.70 mg/kg/min by methyltestosterone (P < 0.05). The ratio of glucose uptake per unit of insulin was also significantly reduced from a control study value of 14.3+/-1.4 to 9.4+/-1.3 mg/kg/min per microU/mL x 100 during methyltestosterone administration. In the euglycemic hyperinsulinemic clamp studies, insulin was infused at rates of 0.25 and 1.0 mU/kg/min to achieve insulin levels of approximately 25 and 68 microU/mL, respectively. During low-dose insulin infusion, rates of endogenous hepatic glucose production were equivalently suppressed from basal values of 2.37+/-0.29 and 2.40+/-0.27 mg/kg/min to 0.88+/-0.25 and 0.77+/-0.26 mg/kg/min in the methyltestesterone and control studies respectively. Whole body glucose uptake during low-dose insulin infusion was minimally affected. During the high-dose insulin infusion, endogenous hepatic glucose production was nearly totally suppressed in both groups. However, whole body glucose uptake was reduced from the control value of 6.11+/-0.49 mg/kg/min to 4.93+/-0.44 mg/kg/min during methyltestosterone administration (P < 0.05). Our data demonstrate that androgen excess leads to the development of insulin resistance during both hyperglycemic and euglycemic hyperinsulinemia. These findings provide direct evidence for a relationship between hyperandrogenemia and insulin resistance, and its associated risk factors for cardiovascular disease.
Assuntos
Resistência à Insulina/fisiologia , Insulina/metabolismo , Metiltestosterona/farmacologia , Congêneres da Testosterona/farmacologia , Adulto , Relação Dose-Resposta a Droga , Feminino , Glucose/antagonistas & inibidores , Glucose/metabolismo , Técnica Clamp de Glucose , Homeostase/efeitos dos fármacos , Humanos , Hiperinsulinismo/sangue , Hiperinsulinismo/metabolismo , Hipoglicemiantes/farmacologia , Insulina/farmacologia , Secreção de Insulina , Fígado/metabolismoRESUMO
Although assessment of counterregulatory hormone responses to hypoglycemia relies upon insulin to lower the glucose level, it is not known if the exogenous insulin does used itself influences the magnitude of the hormone response. To assess this, 12 normal subjects randomly received 2 hypoglycemic clamp studies in which the only variable was the insulin dose (0.6 or 5.0 mU/kg-min). Despite 10-fold differences in circulating insulin (265 +/- 29 vs 2576 +/- 222 pmol/L respectively), the hypoglycemic stimulus did not vary. Glucose levels fell over one hour, and then were maintained for two hours at the same hypoglycemic plateau (approximately 3.1 mmol/L for each study) by a variable glucose infusion. Although basal counterregulatory hormone levels in low and high dose studies were indistinguishable, during hypoglycemia the response of epinephrine, growth hormone, and glucagon was significantly suppressed when the degree of hyperinsulinemia was increased. We conclude that raising the magnitude of hyperinsulinemia suppresses the magnitude of the counterregulatory hormone response to hypoglycemia in normal subjects. This modulating effect of insulin per se is yet another variable in the interpretation of hypoglycemic counterregulation.
Assuntos
Epinefrina/sangue , Glucagon/sangue , Hormônio do Crescimento/sangue , Hipoglicemia/sangue , Insulina/farmacologia , Adulto , Relação Dose-Resposta a Droga , Feminino , Técnica Clamp de Glucose , Humanos , MasculinoRESUMO
In systemic carnitine deficiency, an early phase of nonketotic hypoglycemia and liver dysfunction may precede a late phase of encephalopathy and myopathy. We studied two children with recurrent episodes of nonketotic hypoglycemia who were found to have systemic carnitine deficiency without myopathy or encephalopathy. Early institution of appropriate therapy prevented the onset of late debilitating complications in one patient, whereas therapeutic noncompliance in the other patient led to an episode of encephalopathy and myopathy. Metabolic studies indicated that decreased availability of alanine may be a factor in the genesis of hypoglycemia; concurrent depletion of cerebral glucose, ketones, and glycogen may be the cause of the encephalopathy.