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1.
Front Endocrinol (Lausanne) ; 14: 1201547, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37766684

RESUMO

Introduction: The pharmacological target for progesterone, different progestins, and Selective Progesterone Receptor Modulators (SPRMs) is the nuclear progesterone receptor (PR). EC313 is a new member of a subgroup of SPRMs, mesoprogestins, which combine especially PR- agonistic and PR-antagonistic activities in one molecule. Methods: The suitable in vivo-model for the differentiation of SPRMs from the subgroup of mesoprogestins is the estrogen-primed juvenile rabbit endometrium assay (McPhail Assay). Remarkably, in contrast to other well-known SPRMs with no agonistic effects in this test, EC313 shows clear partial PR-agonistic effects that are higher than that of the well-known mesoprogestin Asoprisnil which already demonstrated remarkable clinical effectiveness for the treatment of uterine fibroids and endometriosis. The findings from the guinea pig studies presented here can be the impetus for further preclinical development of EC313. This model shows the same features for the termination of pregnancy by antiprogestins such as Mifepristone and Ulipristal acetate (UPA) in humans. Moreover, it is possible to distinguish between progestational and anti-progestational activities in the same experiment. Results: The EC313 treatment reveals PR dominance in the genital tract and inhibits unopposed estrogenic effects. In very high doses (30.0 mg/animal/day subcutaneously (s.c.)) given twice on pregnancy days 43 and 44, no premature labor was induced (in contrast to UPA, dosed at 10.0 and 30. mg/animal/day s.c.). The anti-ovulatory activity of EC313 exceeds that of Ulipristal acetate or Mifepristone. EC313 binds to the steroid receptors in vitro with a similar affinity as the natural ligand progesterone. At the glucocorticoid receptor (GR) EC313 acts as a weak inhibitor. Minor activities at the human androgen receptor (AR) and mineralocorticoid receptor (MR) are considered negligible. No binding to the estradiol receptor was detected. In contrast to some in vitro-receptor findings, estrogenic, anti-estrogenic, androgenic, anti-androgenic, glucocorticoid, and anti-glucocorticoid actions were absent in vivo. The tissue selectivity of EC313 was demonstrated previously by reducing the growth and proliferation of uterine fibroids in animal models (lowest effective dosage 0.1 mg/kg/day s.c.).. As shown in this article, the anti-fibroid activity of EC313 was confirmed with a 10 times lower dosage (0.01 mg/kg/day s.c.). It was also shown that EC313 reduces the growth of endometriotic lesions in a human xenograft immune-deficient (NOD-SCID) mice model with a comparatively very low dosage range. In the aforementioned EC313 activity model, UPA was tested as the reference compound, the clinical effectiveness of which has already been demonstrated. Discussion: For an explanation of these findings, the possibility is discussed that the mixed agonistic/antagonistic feature of EC313 is tissue target-specific based on its super-additive synergism characteristic for active bifunctional agents. In conclusion, the specific pharmacodynamic profile of this compound opens the possibility for the development of a drug with a distinct pharmaco-endocrinological profile against uterine fibroids, endometriosis, and other PR-dependent gynecological diseases.


Assuntos
Endometriose , Receptores de Progesterona , Camundongos , Feminino , Gravidez , Humanos , Animais , Cobaias , Coelhos , Camundongos Endogâmicos NOD , Camundongos SCID , Progesterona , Mifepristona/farmacologia , Progestinas , Estrogênios
2.
An Acad Bras Cienc ; 94(3): e20210902, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35857934

RESUMO

This study investigated whether increased food intake after 15 days of low-protein, high-carbohydrate (LPHC) and its normalization in the later period of development change the content of key proteins related to leptin or adiponectin signaling in the hypothalamus. Male rats were divided into five groups: Control groups received a control diet (17% protein, 63% carbohydrate) for 15 (C15) or 45 (C45) days; LPHC groups received an LPHC diet (6% protein, 74% carbohydrate) for 15 (LPHC15) or 45 (LPHC45) days; and Reverse group (R): received LPHC diet for 15 days followed by control diet for another 30 days. The LPHC15 group showed increased adiposity index, leptin level, and adiponectin level, as well as decreased the leptin receptor (ObRb) and pro-opiomelanocortin (POMC) content in the hypothalamus compared with the C15 group. LPHC diet for 45 days or diet reversion (R group) rescued these alterations, except the adiponectin level in LPHC45 rats, which was higher. In summary, LPHC diet reduced hypothalamic leptin action by diminishing ObRb and POMC levels, leading to hyperphagia and adiposity body. Medium-term administration of LPHC diet or reverting to control diet restored the levels of these proteins, thereby improving body lipid mass rearrangement in adulthood.


Assuntos
Leptina , Pró-Opiomelanocortina , Adiponectina , Animais , Carboidratos , Dieta com Restrição de Proteínas , Hiperfagia/etiologia , Hiperfagia/metabolismo , Leptina/metabolismo , Masculino , Obesidade/metabolismo , Pró-Opiomelanocortina/metabolismo , Ratos , Ratos Wistar
3.
Int J Lab Hematol ; 43(4): 724-731, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33393719

RESUMO

INTRODUCTION: Minimal residual disease (MRD) is a cornerstone for stratification of upfront B-lymphoblastic leukemia (B-ALL) treatment protocols to decrease relapse risk. Although its detection by flow cytometry (FC) and real-time quantitative polymerase has clinical usefulness, evidence suggests that methods with increased sensitivity could lead to improved outcomes. The aim of this study was to develop an amplicon-based assay followed by high-throughput sequencing of the immunoglobulin heavy chain variable region for MRD detection in B-ALL. METHODS: We analyzed 84 samples, 27 from diagnosis, 5 from relapse, 40 from post-treatment samples, and 12 from healthy controls. RESULTS: Our assay was able to identify more neoplastic clones at diagnosis than Sanger sequencing including incomplete DJ rearrangements. From the 40 MRD samples evaluated 21 were positive by our new approach on high-throughput sequencing assay, but only 15 of these were positive by FC. The remaining 19 were negative by the two techniques. CONCLUSION: We have developed a novel approach on high-sensitive assay for MRD detection in B-ALL, which could add clinical value in the management of patients, especially in cases negative for MRD by FC.


Assuntos
Cadeias Pesadas de Imunoglobulinas/genética , Neoplasia Residual/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Neoplasia Residual/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras B/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras B/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico
4.
Colorectal Dis ; 21(7): 775-781, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30848537

RESUMO

AIM: Studies addressing the benefit of early intervention are prone to lead-time bias, which results in an artificial improvement in cancer-specific mortality. We have previously compared the age at death for patients with colorectal cancer presenting on an emergency or elective basis. In this study, we aimed to repeat the analysis with a minimum follow-up of 10 years. METHOD: A nonscreen-detected cohort of patients presenting with colorectal cancer to three Lanarkshire Hospitals between 2000 and 2006 were entered into a prospective database, with analysis performed on 28 November 2016. The following data were collected: age at death, presentation type (emergency/elective), operative intent (palliative/curative) and Dukes stage. Results are presented as [mean (95% confidence intervals)]. Statistical analysis was undertaken using Student's t-test and multivariate analysis performed using Cox proportional hazard models. RESULTS: One thousand six hundred and thirty-six patients were identified. Elective patients presented younger than emergency patients [67.9 (67.3-68.5) vs 70.9 (69.6-72.2) years; P < 0.0001]. Overall mortality was 71.1% at time of analysis; no difference was seen in the mean age at death between emergency and elective presentation [73.5 (72.4-74.8) vs 73.6 (72.3-74.9) years; P = 0.841]. CONCLUSION: Current early detection strategies to diagnose colorectal cancer may improve cancer-specific survival by increasing lead-time bias. However, in our cohort of symptomatic patients, treatment on an elective or emergency basis does not influence overall survival. These data suggest that in selected patients, particularly where there is comorbidity, it may be reasonable to adopt a more expectant approach to investigate and treat colorectal symptoms.


Assuntos
Fatores Etários , Neoplasias Colorretais/mortalidade , Procedimentos Cirúrgicos Eletivos/mortalidade , Tratamento de Emergência/mortalidade , Fatores de Tempo , Idoso , Viés , Neoplasias Colorretais/patologia , Neoplasias Colorretais/cirurgia , Bases de Dados Factuais , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Modelos de Riscos Proporcionais , Estudos Prospectivos
5.
Gut ; 67(2): 299-306, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-27789658

RESUMO

OBJECTIVES: Colorectal polyp cancers present clinicians with a treatment dilemma. Decisions regarding whether to offer segmental resection or endoscopic surveillance are often taken without reference to good quality evidence. The aim of this study was to develop a treatment algorithm for patients with screen-detected polyp cancers. DESIGN: This national cohort study included all patients with a polyp cancer identified through the Scottish Bowel Screening Programme between 2000 and 2012. Multivariate regression analysis was used to assess the impact of clinical, endoscopic and pathological variables on the rate of adverse events (residual tumour in patients undergoing segmental resection or cancer-related death or disease recurrence in any patient). These data were used to develop a clinically relevant treatment algorithm. RESULTS: 485 patients with polyp cancers were included. 186/485 (38%) underwent segmental resection and residual tumour was identified in 41/186 (22%). The only factor associated with an increased risk of residual tumour in the bowel wall was incomplete excision of the original polyp (OR 5.61, p=0.001), while only lymphovascular invasion was associated with an increased risk of lymph node metastases (OR 5.95, p=0.002). When patients undergoing segmental resection or endoscopic surveillance were considered together, the risk of adverse events was significantly higher in patients with incomplete excision (OR 10.23, p<0.001) or lymphovascular invasion (OR 2.65, p=0.023). CONCLUSION: A policy of surveillance is adequate for the majority of patients with screen-detected colorectal polyp cancers. Consideration of segmental resection should be reserved for those with incomplete excision or evidence of lymphovascular invasion.


Assuntos
Algoritmos , Pólipos do Colo/patologia , Pólipos do Colo/cirurgia , Neoplasias Colorretais/patologia , Neoplasias Colorretais/cirurgia , Recidiva Local de Neoplasia/diagnóstico , Conduta Expectante , Idoso , Vasos Sanguíneos/patologia , Colectomia , Colonoscopia , Intervalo Livre de Doença , Detecção Precoce de Câncer , Medicina Baseada em Evidências , Feminino , Humanos , Metástase Linfática , Vasos Linfáticos/patologia , Masculino , Invasividade Neoplásica , Neoplasia Residual , Fatores de Risco , Escócia , Taxa de Sobrevida
6.
Indian J Cancer ; 54(1): 301-304, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29199709

RESUMO

CONTEXT: The hypofractionated stereotactic body radiation therapy (SBRT) has emerged as a safe and effective treatment modality for early-stage nonsmall cell lung carcinoma. AIMS: An audit SBRT in primary lung cancer treated in our center with and without an active breath coordinator (ABC) was undertaken to evaluate its impact on target volumes and clinical outcomes. SETTINGS AND DESIGN: This was an observational study. MATERIALS AND METHODS: Nine patients with lung carcinoma were treated from January 2014 to August 2016. Five patients were simulated using ABC and four patients with free breathing. Volumetric modulated arc therapy plans were generated using Monaco treatment planning software. Three patients were treated with a dose of 54 Gy in three fractions and six patients with a dose of 48 Gy in four fractions. STATISTICAL ANALYSIS USED: The statistical analysis was performed using Kaplan-Meier survival. RESULTS: The mean planning target volumes (PTV) in ABC and free breathing groups were 42.19cc and 60.17cc, respectively. The mean volume of lung receiving 20, 10, and 5 Gy (V20, V10and V5) in ABC group were 5.37cc, 10.49cc, and 18.45cc whereas in free breathing 6.63cc, 12.74cc, and 20.64cc, respectively. At a median follow-up of 18 months, there were three local recurrences. No significant toxicity occurred in our series. CONCLUSION: Our initial results show that SBRT is well tolerated with good local control. Although the PTV volume and irradiated normal lung volume was higher in this group compared to ABC group, this did not translate to any added clinical toxicity.


Assuntos
Neoplasias Pulmonares/epidemiologia , Neoplasias Pulmonares/radioterapia , Recidiva Local de Neoplasia/epidemiologia , Recidiva Local de Neoplasia/radioterapia , Idoso , Feminino , Humanos , Pulmão/fisiopatologia , Pulmão/efeitos da radiação , Neoplasias Pulmonares/fisiopatologia , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Radiocirurgia/efeitos adversos , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Radioterapia de Intensidade Modulada/efeitos adversos , Mecânica Respiratória , Resultado do Tratamento
7.
Indian J Cancer ; 54(1): 316-320, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29199713

RESUMO

AIM: The aim of this retrospective study is to assess the toxicity and tumor response of stereotactic body radiation therapy (SBRT) protocol for hepatocellular carcinoma (HCC) in our institution. BACKGROUND: Hepatocellular cancer is one of the leading cancers among men in India. In recent years, SBRT has emerged as a promising tool in the treatment of HCC. MATERIALS AND METHODS: Ten patients diagnosed as HCC with Barcelona Clinic Liver Cancer Stage B and C, treated with SBRT technique from January 2013 to December 2016, were included in this study. SBRT was delivered using 6 MV photons with volumetric modulated arc therapy. Acute and late toxicities were graded, and tumor response was assessed using response evaluation criteria in solid tumors criteria. Kaplan-Meier curves were generated for progression-free survival (PFS) and overall survival (OS). RESULTS: The median age was 61.5 (52-69) years. The radiation dose ranged from 35 Gy to 60 Gy. All patients obtained partial response during assessment at 3 months after completion of treatment. The median PFS is 8 months (95% confidence interval [CI] - 5.22-10.77 months). The median OS is 51 months (95% CI - 17.64-65.10 months). The OS at 1 and 2 years is 75% and 57%, respectively. CONCLUSIONS: SBRT is well tolerated by our patients. The 1- and 2-year OS of 75% and 57% is consistent with other prospective and retrospective SBRT studies from the literature.


Assuntos
Carcinoma Hepatocelular/radioterapia , Neoplasias Hepáticas/radioterapia , Radiocirurgia , Centros de Atenção Terciária , Idoso , Carcinoma Hepatocelular/epidemiologia , Carcinoma Hepatocelular/patologia , Feminino , Humanos , Índia/epidemiologia , Neoplasias Hepáticas/epidemiologia , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade
8.
Nutrition ; 42: 37-45, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28870477

RESUMO

OBJECTIVE: The aim of this study was to evaluate the browning and origin of fatty acids (FAs) in the maintenance of triacylglycerol (TG) storage and/or as fuel for thermogenesis in perirenal adipose tissue (periWAT) and inguinal adipose tissue (ingWAT) of rats fed a low-protein, high-carbohydrate (LPHC) diet. METHODS: LPHC (6% protein, 74% carbohydrate) or control (C; 17% protein, 63% carbohydrate) diets were administered to rats for 15 d. The tissues were stained with hematoxylin and eosin for histologic analysis. The content of uncoupling protein 1 (UCP1) was determined by immunofluorescence. Levels of T-box transcription factor (TBX1), PR domain containing 16 (PRDM16), adipose triacylglycerol lipase (ATGL), hormone-sensitive lipase, lipoprotein lipase (LPL), glycerokinase, phosphoenolpyruvate carboxykinase (PEPCK), glucose transporter 4, ß3-adrenergic receptor (AR), ß1-AR, protein kinase A (PKA), adenosine-monophosphate-activated protein kinase (AMPK), and phospho-AMPK were determined by immunoblotting. Serum fibroblast growth factor 21 (FGF21) was measured using a commercial kit (Student's t tests, P < 0.05). RESULTS: The LPHC diet increased FGF21 levels by 150-fold. The presence of multilocular adipocytes, combined with the increased contents of UCP1, TBX1, and PRDM16 in periWAT of LPHC-fed rats, suggested the occurrence of browning. The contents of ß1-AR and LPL were increased in the periWAT. The ingWAT showed higher ATGL and PEPCK levels, phospho-AMPK/AMPK ratio, and reduced ß3-AR and PKA levels. CONCLUSION: These findings suggest that browning occurred only in the periWAT and that higher utilization of FAs from blood lipoproteins acted as fuel for thermogenesis. Increased glycerol 3-phosphate generation by glyceroneogenesis increased FAs reesterification from lipolysis, explaining the increased TG storage in the ingWAT.


Assuntos
Tecido Adiposo Marrom/metabolismo , Dieta com Restrição de Proteínas/métodos , Carboidratos da Dieta/administração & dosagem , Rim/metabolismo , Tecido Adiposo Marrom/efeitos dos fármacos , Animais , Dieta/métodos , Fatores de Crescimento de Fibroblastos/sangue , Imunofluorescência , Canal Inguinal , Rim/efeitos dos fármacos , Masculino , Modelos Animais , Ratos , Ratos Wistar
9.
J Steroid Biochem Mol Biol ; 165(Pt B): 305-311, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27449818

RESUMO

Oral compared to parenteral estrogen administration is characterized by reduced systemic but prominent hepatic estrogenic effects on lipids, hemostatic factors, GH-/IGF I axis, angiotensinogen. In order to avoid such adverse metabolic effects of oral treatment, estradiol (E2) prodrugs (EP) were designed which bypass the liver tissue as inactive molecules. Carbone17-OH sulfonamide [-O2-NH2] substituted esters of E2 (EC508, others) were synthesized and tested for carbonic anhydrase II (CA-II) binding. CA II in erythrocytes is thought to oppose extraction of EP from portal vein blood during liver passage. Ovariectomized (OVX, day minus 14) rats were orally treated once daily from day 1-3. Sacrifice day 4. Uteri were dissected and weighed. Cholesterol fractions and angiotensinogen were determined in plasma. Oral E2 and ethinyl estradiol (EE) generated dose related uterine growth and important hepatic estrogenic effects. EP induced uterine growth at about hundred-fold lower doses. This was possible with almost absent effects on plasma cholesterol or angiotensinogen. Preliminary pharmacokinetic studies with EC508 used intravenous and oral administration in male rats. Resulting blood levels revealed complete oral bioavailability. Further high blood- but low plasma concentrations indicated erythrocyte binding of EC508 in vivo as potential mechanism of low extraction at liver passage. Very high systemic estrogenicity combined with markedly lower or absent adverse hepatic estrogenic effects is evidence for a systemic release of E2 from sulfonamide EP. In conclusion, tested oral EP bypass the liver in erythrocytes furnishing systemic estradiol at hydrolysis. This mechanism avoids the hepatic estrogenic impact of conventional oral estrogen therapy.


Assuntos
Estradiol/farmacologia , Estrogênios/administração & dosagem , Fígado/metabolismo , Pró-Fármacos/farmacologia , Administração Oral , Angiotensinogênio/sangue , Animais , Disponibilidade Biológica , Anidrase Carbônica II/metabolismo , Colesterol/sangue , Eritrócitos/citologia , Eritrócitos/metabolismo , Ésteres/química , Feminino , Humanos , Hidrólise , Fígado/efeitos dos fármacos , Masculino , Ovariectomia , Ratos , Ratos Sprague-Dawley , Especificidade da Espécie , Sulfonamidas/química , Tromboembolia , Útero/efeitos dos fármacos
10.
Int J Surg Case Rep ; 11: 68-70, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25935734

RESUMO

INTRODUCTION: Internal herniae, although rare, can give rise to potentially serious morbidity and mortality. The protrusion and entrapment of the small bowel through an embryological or iatrogenic mesenteric aperture within the confines of the peritoneal cavity can be difficult to diagnose, and delay treatment (operative). Timely intervention must be achieved to minimize small bowel ischemia and infarction. CASE PRESENTATION: In this case, a young lady who had a previous laparoscopic total colectomy and ileostomy developed an unusual internal hernia. Small bowel was passing behind the lesser curvature of the stomach causing the stomach to be rotated to form of a tight "band" trapping bowel. The herniated small bowel was reduced, hence, avoiding resection; the defect closed by interupted 4-0 PDS. "Prompt" surgery avoided small bowel length resection and sacrifice of the ileoanal pouch reconstruction. DISCUSSION: It is theorized that a laparoscopic approach results in a more advanced mobilization of the mesentery right up to the small bowel origin, and with less adhesion formation may in fact promote unusual internal hernia and volvulus. CONCLUSION: The case presented highlights the difficulty in making the diagnosis, and the pictures clearly indicate an unusual hernia passing directly behind the stomach and involving a large section of the small bowel. The lead up history of several admissions with sub acute small bowel obstruction suggested the underlying problem was adhesional but quite clearly there was a well defined internal hernia. Without timely surgery she would have been at high risk of losing her pouch.

11.
Cell Death Discov ; 1: 15061, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-27551486

RESUMO

As breast cancer cells often develop chemoresistance, better therapeutic options are in search to circumvent it. Here we demonstrate that human epidermal growth factor receptor-2 (HER-2)-overexpressing breast cancer cells resist docetaxel-induced cytotoxicity by upregulating HER-2 and its activity downstream, through Akt and mitogen-activated protein kinase (MAPK) pathways. We observed that introducing resveratrol as a chemosensitizer in docetaxel chemotherapy blocks upregulation and activation of HER-2 in addition to blocking downstream signaling pathways such as Akt. Resveratrol and docetaxel combination results in the synergistic induction of cell death in HER-2-overexpressing SK-BR-3 cells, whereas introduction of wild-type HER-2 in MDA-MD-231 cells increased the resistance to docetaxel. Dominant-negative HER-2 sensitizes SK-BR-3 cells to docetaxel. Our study identified a new synergistic therapeutic combination that targets HER-2-induced breast cancer resistance and might help to overcome therapeutic resistance during breast cancer therapy. The synergism of docetaxel and resveratrol was maximum in SK-BR-3, which is unique among the cell lines studied, due to its high expression status of HER-2, a receptor known to dictate the signaling environment of breast cancer cells. Docetaxel could further induce HER-2 activity in these cells, which was downregulated on resveratrol treatment. Transfection of DN-HER-2 in SK-BR-3 cells inhibits the synergism as the transfection itself sensitizes these cells to docetaxel, leaving no role for resveratrol, whereas ectopic expression of HER-2 introduces the synergism in MDA-MB-231, the triple-negative cell line, in which the synergism was minimum, attesting the crucial role of HER-2 in suppressing the sensitivity to docetaxel. Single-agent docetaxel induced HER-2-mediated resistance to cell death, which was blocked by resveratrol. Resveratrol also downregulated docetaxel-induced activation of MAPK and Akt, survival signaling pathways downstream of HER-2. In short, this study, for the first time, establishes the role of HER-2-Akt signaling axis in regulating the synergistic effect of docetaxel and resveratrol in breast cancer cells overexpressing HER-2.

12.
Lipids ; 48(8): 779-86, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23794137

RESUMO

The aim of this study was to investigate tumor necrosis factor alpha (TNF-α)- and noradrenaline (NE)-stimulated lipolysis in retroperitoneal (RWAT) and epididymal (EAT) white adipose tissue as a means of understanding how low-protein, high-carbohydrate (LPHC) diet-fed rats maintain their lipid storage in a catabolic environment (marked by increases in serum TNF-α and corticosterone and sympathetic flux to RWAT and EAT), as previously observed. Adipocytes or tissues from the RWAT and EAT of rats fed an LPHC diet and rats fed a control (C) diet for 15 days were used in the experiments. The adipocytes from both tissues of the LPHC rats exhibited lower TNF-α- stimulated lipolysis compared to adipocytes from the C rats. The intracellular lipolytic agents IBMX, DBcAMPc and FSK increased lipolysis in both tissues from rats fed the C and LPHC diets compared to basal lipolysis; however, the effect was approximately 2.5-fold lower in adipocytes from LPHC rats. The LPHC diet induced a marked reduction in the ß3 and α2-AR, adipose triglyceride lipase (ATGL) and hormone-sensitive lipase (HSL) content in RWAT and EAT. The LPHC diet did not affect TNF-α receptor 1 content but did induce a reduction in ERK p44/42 in both tissues. The present work indicates that RWAT and EAT from LPHC rats have an impairment in the lipolysis signaling pathway activated by NE and TNF-α, and this impairment explains the reduced response to these lipolytic stimuli, which may be fundamental to the maintenance of lipid storage in LPHC rats.


Assuntos
Adipócitos/metabolismo , Dieta com Restrição de Proteínas , Lipólise/fisiologia , Norepinefrina/farmacologia , Fator de Necrose Tumoral alfa/farmacologia , 1-Metil-3-Isobutilxantina/farmacologia , Adipócitos/efeitos dos fármacos , Tecido Adiposo Branco/efeitos dos fármacos , Tecido Adiposo Branco/crescimento & desenvolvimento , Tecido Adiposo Branco/metabolismo , Animais , Peso Corporal/efeitos dos fármacos , Bucladesina/farmacologia , Dieta , Carboidratos da Dieta/farmacologia , Lipase/metabolismo , Lipólise/efeitos dos fármacos , Masculino , Norepinefrina/metabolismo , Ratos , Ratos Wistar , Receptores Adrenérgicos alfa 2/metabolismo , Receptores Adrenérgicos beta 3/metabolismo , Receptores do Fator de Necrose Tumoral/metabolismo , Esterol Esterase/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
13.
Cell Death Dis ; 4: e505, 2013 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-23429291

RESUMO

5-Fluorouracil (5-FU) is the first rationally designed antimetabolite, which achieves its therapeutic efficacy through inhibition of the enzyme thymidylate synthase (TS), which is essential for the synthesis and repair of DNA. However, prolonged exposure to 5-FU induces TS overexpression, which leads to 5-FU resistance in cancer cells. Several studies have identified curcumin as a potent chemosensitizer against chemoresistance induced by various chemotherapeutic drugs. In this study, we report for the first time, with mechanism-based evidences, that curcumin can effectively chemosensitize breast cancer cells to 5-FU, thereby reducing the toxicity and drug resistance. We found that 10 µM 5-FU and 10 µM curcumin induces a synergistic cytotoxic effect in different breast cancer cells, independent of their receptor status, through the enhancement of apoptosis. Curcumin was found to sensitize the breast cancer cells to 5-FU through TS-dependent downregulation of nuclear factor-κB (NF-κB), and this observation was confirmed by silencing TS and inactivating NF-κB, both of which reduced the chemosensitizing efficacy of curcumin. Silencing of TS suppressed 5-FU-induced NF-κB activation, whereas inactivation of NF-κB did not affect 5-FU-induced TS upregulation, confirming that TS is upstream of NF-κB and regulates the activation of NF-κB in 5-FU-induced signaling pathway. Although Akt/PI3kinase and mitogen-activated protein kinase pathways are activated by 5-FU and downregulated by curcumin, they do not have any role in regulating the synergism. As curcumin is a pharmacologically safe and cost-effective compound, its use in combination with 5-FU may improve the therapeutic index of 5-FU, if corroborated by in vivo studies and clinical trials.


Assuntos
Antineoplásicos/farmacologia , Curcumina/farmacologia , Fluoruracila/farmacologia , Transdução de Sinais/efeitos dos fármacos , Anexina A5/metabolismo , Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Caspases/metabolismo , Linhagem Celular Tumoral , Curcumina/uso terapêutico , Fragmentação do DNA/efeitos dos fármacos , Regulação para Baixo , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Sinergismo Farmacológico , Feminino , Fluoruracila/uso terapêutico , Humanos , Células MCF-7 , Proteínas Quinases Ativadas por Mitógeno/metabolismo , NF-kappa B/metabolismo , Poli(ADP-Ribose) Polimerases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Timidilato Sintase/antagonistas & inibidores , Timidilato Sintase/genética , Timidilato Sintase/metabolismo , Regulação para Cima
14.
Lipids ; 47(3): 279-89, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22228227

RESUMO

A low-protein, high-carbohydrate (LPHC) diet for 15 days increased the lipid content in the carcass and adipose tissues of rats. The aim of this work was to investigate the mechanisms of this lipid increase in the retroperitoneal white adipose tissue (RWAT) of these animals. The LPHC diet induced an approximately two- and tenfold increase in serum corticosterone and TNF-α, respectively. The rate of de novo fatty acid (FA) synthesis in vivo was reduced (50%) in LPHC rats, and the lipoprotein lipase activity increased (100%). In addition, glycerokinase activity increased (60%), and the phosphoenolpyruvate carboxykinase content decreased (27%). Basal [U-¹4C]-glucose incorporation into glycerol-triacylglycerol did not differ between the groups; however, in the presence of insulin, [U-¹4C]-glucose incorporation increased by 124% in adipocytes from only control rats. The reductions in IRS1 and AKT content as well as AKT phosphorylation in the RWAT from LPHC rats and the absence of an insulin response suggest that these adipocytes have reduced insulin sensitivity. The increase in NE turnover by 45% and the lack of a lipolytic response to NE in adipocytes from LPHC rats imply catecholamine resistance. The data reveal that the increase in fat storage in the RWAT of LPHC rats results from an increase in FA uptake from circulating lipoproteins and glycerol phosphorylation, which is accompanied by an impaired lipolysis that is activated by NE.


Assuntos
Dieta com Restrição de Proteínas , Ácidos Graxos/metabolismo , Gordura Intra-Abdominal/metabolismo , Norepinefrina/metabolismo , Animais , Dieta , Glucose/metabolismo , Hiperfagia/metabolismo , Lipólise , Masculino , Ratos
15.
Oncogene ; 31(7): 907-17, 2012 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-21743488

RESUMO

A large fraction of ductal carcinoma in situ (DCIS), a non-invasive precursor lesion of invasive breast cancer, overexpresses the HER2/neu oncogene. The ducts of DCIS are abnormally filled with cells that evade apoptosis, but the underlying mechanisms remain incompletely understood. We overexpressed HER2 in mammary epithelial cells and observed growth factor-independent proliferation. When grown in extracellular matrix as three-dimensional spheroids, control cells developed a hollow lumen, but HER2-overexpressing cells populated the lumen by evading apoptosis. We demonstrate that HER2 overexpression in this cellular model of DCIS drives transcriptional upregulation of multiple components of the Notch survival pathway. Importantly, luminal filling required upregulation of a signaling pathway comprising Notch3, its cleaved intracellular domain and the transcriptional regulator HES1, resulting in elevated levels of c-MYC and cyclin D1. In line with HER2-Notch3 collaboration, drugs intercepting either arm reverted the DCIS-like phenotype. In addition, we report upregulation of Notch3 in hyperplastic lesions of HER2 transgenic animals, as well as an association between HER2 levels and expression levels of components of the Notch pathway in tumor specimens of breast cancer patients. Therefore, it is conceivable that the integration of the Notch and HER2 signaling pathways contributes to the pathophysiology of DCIS.


Assuntos
Neoplasias da Mama/genética , Carcinoma Intraductal não Infiltrante/genética , Receptor ErbB-2/genética , Receptores Notch/genética , Animais , Neoplasias da Mama/metabolismo , Carcinoma Intraductal não Infiltrante/metabolismo , Linhagem Celular , Proliferação de Células , Fator de Crescimento Epidérmico/farmacologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Feminino , Perfilação da Expressão Gênica , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Células HEK293 , Humanos , Immunoblotting , Glândulas Mamárias Humanas/citologia , Glândulas Mamárias Humanas/metabolismo , Camundongos , Camundongos Transgênicos , Microscopia Confocal , Modelos Biológicos , Análise de Sequência com Séries de Oligonucleotídeos , Interferência de RNA , Receptor ErbB-2/metabolismo , Receptor Notch3 , Receptores Notch/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/genética , Transfecção
17.
Arq. bras. endocrinol. metab ; 53(1): 87-94, fev. 2009. graf, tab
Artigo em Português | LILACS | ID: lil-509870

RESUMO

Foram avaliadas as alterações no metabolismo materno durante a prenhez em ratas Wistar, prenhes e não-prenhes, submetidas à restrição protéica, que receberam dietas isocalóricas (15,74 kJ/g), controle ou hipoprotéica (17 por cento versus 6 por cento), distribuídas em quatro grupos (n = 7), quais sejam: controle não-prenhe (CNP) e prenhe (CP) e hipoprotéico não-prenhe (HNP) e prenhe (HP), do 1º ao 18º dia de prenhez. Parâmetros bioquímicos, hormonais e relacionados à síntese de lipídios foram considerados. Utilizou-se ANOVA a duas vias seguido de teste Tukey-HSD e teste t de Student, significância de p < 0,05. A restrição protéica elevou a síntese de lipídios e a atividade da enzima málica (EM) no fígado (FIG) e reduziu a massa ( por cento) e a razão lipí+dio/glicogênio nesse tecido, bem como reduziu a ingestão protéica (total e por cento), o conteúdo ( por cento) de lipídios na glândula mamária (GMA), as proteínas e a albumina séricas, com consequente redução nas massas da placenta e fetos. A prenhez reduziu a proteinemia, a albuminemia, a síntese de lipídios, a atividade da EM, os lipídios e o glicogênio no FIG. Mas elevou a massa corporal final, a massa ( por cento) do tecido adiposo gonadal (GON), do FIG e da GMA, e reduziu a massa ( por cento) da carcaça (CARC), a síntese e o conteúdo de lipídios no GON e, na GMA, o conteúdo de lipídios. A insulinemia elevou-se na prenhez, com glicemia reduzida, caracterizando resistência hormonal. A leptina e a prolactina também se elevaram na prenhez, sendo o aumento maior no HP. A restrição protéica na prenhez modificou o metabolismo materno, alterando a síntese de lipídios no FIG e o perfil hormonal, além de reduzir a massa da placenta e dos fetos.


Metabolism alterations were evaluated in female Wistar rats (dams) during pregnancy. Pregnant and non-pregnant dams submitted to protein restriction, were fed isocaloric (15.74 kJ/g), control or hypoproteic (17 percent vs. 6 percent) diets, and distributed in four Groups (n=7) as follows: non-pregnant control (NPC), pregnant control (PC), non-pregnant hypoproteic (NPH), and pregnant hypoproteic (PH); from Day 1 to Day 18 of pregnancy. Biochemical, hormonal and metabolic parameters related to lipid synthesis were assessed. The two-way ANOVA, followed by Tukey-HSD and Student-t tests were used, with a significance of p< 0.05. Protein restriction elevated lipid synthesis and malic enzyme (ME) activity in the liver, and reduced mass and the lipid/glycogen ratio in this tissue; it also lowered protein ingestion (total and percent), lipid content ( percent) in the mammary gland (MAG), serum proteins and albumin, with consequent reduction of placenta and fetal masses. Pregnancy reduced serum protein and albumin concentrations, lipid synthesis, ME activity, hepatic lipid and glycogen content. However, it increased final body mass; increased relative masses of gonad (GON), liver and MAG; but reduced lipid synthesis and content of GON, lipid content of MAG and the relative mass of carcass. Pregnancy Insulinemia increased during pregnancy with reduced glycemia, characterizing hormonal resistance. Leptin and prolactin were also increased during pregnancy, being the highest increase in observed in HP rats. Protein restriction in pregnancy modified maternal metabolism, altering lipid synthesis in the liver and hormonal profile and decreasing the placenta and fetus masses.


Assuntos
Animais , Feminino , Gravidez , Ratos , Dieta com Restrição de Proteínas/efeitos adversos , Fenômenos Fisiológicos da Nutrição Materna/fisiologia , Análise de Variância , Tecido Adiposo/metabolismo , Feto/metabolismo , Gônadas/metabolismo , Hormônios/biossíntese , Lipídeos/biossíntese , Glicogênio Hepático/biossíntese , Fígado/química , Fígado/enzimologia , Modelos Animais , Malato Desidrogenase/biossíntese , Glândulas Mamárias Animais/metabolismo , Placenta/metabolismo , Ratos Wistar
18.
J Neurosci ; 21(12): 4400-7, 2001 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-11404426

RESUMO

The ability to express a behavior during the postnatal period may be related to developmental changes in the recruitment of particular neural systems. Here, we show that developmental changes in the functional interactions involving three cortical regions (the medial prefrontal cortex, orbitofrontal cortex, and anterior cingulate cortex) are associated with maturation of extinction behavior in infant rats. Postnatal day 17 (P17) and P12 pups were trained in a straight-alley runway on an alternating schedule of reward and nonreward [patterned single alternation (PSA)] or on a pseudorandom schedule of partial reinforcement (PRF); the pups were then injected with fluorodeoxyglucose (FDG) and shifted to continuous nonreward (extinction). Handled control groups exposed to the same training environment but not trained on a particular schedule were included. Among P17 pups, extinction proceeded faster in PSA pups relative to PRF pups. No differences were found between P12 groups. FDG uptake, an index of acute changes in functional activity, was quantified in the three cortical regions and 27 other brain regions of interest. A multivariate covariance analysis, seed partial least squares, revealed that functional relationships involving the three cortical regions and large-scale systems of regions throughout the rostrocaudal extent of the brain changed with training in P17 pups. The cortical regions were primarily uncoupled in the younger group. The data suggest that functional maturation of the frontal cortical regions and their interactions with other brain systems are related to the maturational shift in behavior.


Assuntos
Envelhecimento/fisiologia , Comportamento Animal/fisiologia , Extinção Psicológica/fisiologia , Lobo Frontal/fisiologia , Giro do Cíngulo/fisiologia , Animais , Autorradiografia , Mapeamento Encefálico , Radioisótopos de Carbono , Fluordesoxiglucose F18/farmacocinética , Aprendizagem/fisiologia , Atividade Motora/fisiologia , Análise Multivariada , Córtex Pré-Frontal/fisiologia , Ratos , Ratos Sprague-Dawley , Reforço Psicológico , Recompensa , Distribuição Tecidual
19.
J Card Surg ; 16(2): 118-26, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11766829

RESUMO

BACKGROUND AND AIM: Surgical resection of myocardium that acutely reduces left ventricular (LV) volume in patients with advanced heart failure (HF), the so-called "Batista Operation," remains controversial. We examined the effects of acute LV reduction with the Acorn Cardiac Support Device (CSD) in dogs with HF (LV ejection fraction < 30%). METHODS: HF was produced in 15 dogs by intracoronary microembolization. In nine dogs, intravenous dobutamine was administered to reduce LV end-diastolic dimension (LVEDD) by 10%-25%. While on dobutamine infusion, the CSD, a preformed knitted polyester device, was surgically placed around the ventricles, anchored to the arteriovenous (AV) groove, and tailored anteriorly to fit snugly over the ventricles. Dogs were then weaned off dobutamine. RESULTS: On average, the procedure reduced LVEDD by 7 +/- 1 mm (range 5-12 mm). Of the nine dogs, two died before completion of the study and seven survived for the entire period. Six dogs did not undergo device placement and served as controls. All were followed for 3 months prior to sacrifice. In controls, LV end-diastolic volume increased after 3 months (66 +/- 5 mL vs 77 +/- 6 mL; p = 0.007), while in CSD-treated dogs (n = 7), it decreased (80 +/- 5 mL vs 60 +/- 3 mL; p = 0.002). In controls, LV ejection fraction (EF) decreased after 3 months (27 +/- 1% vs 23 +/- 1%; p = 0.001) but was unchanged in CSD-treated dogs (25 +/- 1% vs 26 +/- 1%; p = 0.66). Compared to controls, CSD-treated dogs showed improved LV diastolic dysfunction and chamber sphericity, decreased wall stress, and no functional mitral regurgitation (MR). CONCLUSION: In dogs with advanced HF, acute LV reduction with the Acorn CSD prevents progressive global LV dilatation and ameliorates functional MR.


Assuntos
Insuficiência Cardíaca/cirurgia , Ventrículos do Coração/cirurgia , Coração Auxiliar , Disfunção Ventricular Esquerda/prevenção & controle , Remodelação Ventricular , Doença Aguda , Animais , Doença Crônica , Angiografia Coronária , Dilatação Patológica/prevenção & controle , Progressão da Doença , Cães , Ecocardiografia Doppler , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/fisiopatologia , Ventrículos do Coração/diagnóstico por imagem , Ventrículos do Coração/fisiopatologia , Índice de Gravidade de Doença , Volume Sistólico , Resultado do Tratamento , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Esquerda/fisiopatologia
20.
J Neurosci ; 19(19): 8646-55, 1999 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-10493765

RESUMO

Learning of a behavior at a particular age during the postnatal period presumably occurs when the functional brain circuit mediating the behavior matures. The inability to express a learned behavior, such as inhibition, may be accounted for by the functional dissociation of brain regions comprising the circuit. In this study we tested this hypothesis by measuring brain metabolic activity, as revealed by fluorodeoxyglucose (FDG) autoradiography, during behavioral extinction in 12- and 17-d-old rat pups. Subjects were first trained on a straight alley runway task known as patterned single alternation (PSA), wherein reward and nonreward trials alternate successively. They were then injected with FDG and given 50 trials of continuous nonreward (i.e., extinction). Pups at postnatal day 12 (P12) demonstrated significantly slower extinction rates compared to their P17 counterparts, despite the fact that both reliably demonstrated the PSA effect, i.e., both age groups distinguished between reward and nonreward trials during acquisition. Covariance analysis revealed that the dentate gyrus, hippocampal fields CA1-3, subiculum, and lateral septal area were significantly correlated in P17 but not P12 pups. Significant correlations were also found between the lateral septal area, ventral tegmental area, and the medial septal nucleus in P17 pups. Similar correlative patterns were not found in P12 and P17 handled control animals. Taken together, these results suggest that septal, hippocampal, and mesencephalic regions may be functionally dissociated at P12, and the subsequent maturation of functional connectivity between these regions allows for the more rapid expression of behavioral inhibition during extinction at P17.


Assuntos
Envelhecimento/fisiologia , Mapeamento Encefálico , Encéfalo/fisiologia , Extinção Psicológica/fisiologia , Animais , Encéfalo/crescimento & desenvolvimento , Fluordesoxiglucose F18/farmacocinética , Hipocampo/crescimento & desenvolvimento , Hipocampo/fisiologia , Modelos Neurológicos , Neurônios/fisiologia , Ratos , Ratos Sprague-Dawley , Recompensa , Tegmento Mesencefálico/crescimento & desenvolvimento , Tegmento Mesencefálico/fisiologia
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