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1.
Pract Lab Med ; 35: e00314, 2023 May.
Article En | MEDLINE | ID: mdl-37181647

Objective: Anti-Müllerian Hormone (AMH) is a quantitative marker for ovarian reserve and is used to predict response during ovarian stimulation. Streamlining testing to the clinic or even to the physician's office would reduce inconvenience, turnaround time, patient stress and potentially also the total cost of testing, allowing for more frequent monitoring. In this paper, AMH is used as a model biomarker to describe the rational development and optimization of sensitive, quantitative, clinic-based rapid diagnostic tests. Design and Methods: We developed a one-step lateral-flow europium (III) chelate-based fluorescent immunoassay (LFIA) for the detection of AMH on a portable fluorescent reader, optimizing the capture/detection antibodies, running buffer, and reporter conjugates. Results: A panel of commercial calibrators was used to develop a standard curve to determine the analytical sensitivity (LOD = 0.41 ng/ml) and the analytical range (0.41-15.6 ng/ml) of the LFIA. Commercial controls were then tested to perform an initial evaluation of the prototype performance and showed a high degree of precision (Control I CV 2.18%; Control II CV 3.61%) and accuracy (Control I recovery 126%; Control II recovery 103%). Conclusions: This initial evaluation suggests that, in future clinical testing, the AMH LFIA will likely have the capability of distinguishing women with low ovarian reserve (<1 ng/ml AMH) from women with normal (1-4 ng/ml AMH) ovarian reserve. Furthermore, the LFIA demonstrated a wide linear range, indicating the assay's applicability to the detection of other health conditions such as PCOS, which requires AMH measurement at higher concentrations (>6 ng/ml).

2.
Diabetes Obes Metab ; 23(2): 489-498, 2021 02.
Article En | MEDLINE | ID: mdl-33140542

AIM: To examine how circulating glucagon-like peptide-1 (GLP-1) concentrations during liraglutide treatment relate to its therapeutic actions on glucose and weight, and to study the effects of liraglutide on other proglucagon-derived peptides (PGDPs), including endogenous GLP-1, glucagon-like peptide-2, glucagon, oxyntomodulin, glicentin and major proglucagon fragment, which also regulate metabolic and weight control. MATERIALS AND METHODS: Adults who were overweight/obese (body mass index 27-40 kg/m2 ) with prediabetes were randomized to liraglutide (1.8 mg/day) versus placebo for 14 weeks. We used specific assays to measure exogenous (liraglutide, GLP-1 agonist [GLP-1A]) and endogenous (GLP-1E) GLP-1, alongside five other PGDP concentrations during a mixed meal tolerance test (MMTT) completed at baseline and at week 14 (liraglutide, n = 16; placebo, n = 19). Glucose during MMTT, steady-state plasma glucose (SSPG) concentration for insulin resistance and insulin secretion rate (ISR) were previously measured. MMTT area-under-the-curve (AUC) was calculated for ISR, glucose and levels of PGDPs. RESULTS: Participants on liraglutide versus placebo had significantly (P ≤ .004) decreased weight (mean -3.6%, 95% CI [-5.2% to -2.1%]), SSPG (-32% [-43% to -22%]) and glucose AUC (-7.0% [-11.5% to -2.5%]) and increased ISR AUC (30% [16% to 44%]). GLP-1A AUC at study end was significantly (P ≤ .04) linearly associated with % decrease in weight (r = -0.54) and SSPG (r = -0.59) and increase in ISR AUC (r = 0.51) in the liraglutide group. Treatment with liraglutide significantly (P ≤ .005) increased exogenous GLP-1A AUC (median 310 vs. 262 pg/mL × 8 hours at baseline but decreased endogenous GLP-1E AUC [13.1 vs. 24.2 pmol/L × 8 hours at baseline]), as well as the five other PGDPs. Decreases in the PGDPs processed in the intestines are independent of weight loss, indicating a probable direct effect of GLP-1 receptor agonists to decrease their endogenous production in contrast to weight loss-dependent changes in glucagon and major proglucagon fragment that are processed in pancreatic alpha cells. CONCLUSIONS: Circulating GLP-1A concentrations, reflecting liraglutide levels, predict improvement in weight, insulin action and secretion in a linear manner. Importantly, liraglutide also downregulates other PGDPs, normalization of the levels of which may provide additional metabolic and weight loss benefits in the future.


Glucagon-Like Peptide 1 , Liraglutide , Adult , Body Weight , Glucagon-Like Peptide-1 Receptor , Humans , Insulin/metabolism , Insulin Secretion , Liraglutide/therapeutic use , Peptides , Proglucagon
3.
Article En | MEDLINE | ID: mdl-32499758

The number of mature oocytes is a key factor in the success of Assisted Reproductive Techniques (ART). Exogenous gonadotropins are administered during ovarian stimulation in order to maximize the number of oocytes available for fertilization. During stimulation, monitoring is mandatory to evaluate individual response, to avoid treatment complications and assist in the determination of the optimal day for final oocyte maturation and oocyte retrieval. Routine monitoring during stimulation includes transvaginal ultrasound examinations and measurement of serum estradiol (E2). Due to multifollicular growth of follicles of varying size, serum E2 levels are commonly supraphysiological and often variable, rendering E2-measurement during ovarian stimulation unreliable as a determinant of oocyte maturity. In contrast to serum E2, serum Inhibin A levels increase once a minimum follicle size of 12-15 mm is achieved. Due to this fact, serum Inhibin A levels could present in combination with ultrasound monitoring a more reliable parameter to determine the optimal follicle size for final oocyte maturation, as only follicles with a size of 12 mm and beyond will contribute to the serum Inhibin A level. This prospective observational, cross-sectional study demonstrates, that on the day of final oocyte maturation serum Inhibin A is strongly correlated to the number of follicles ≥15 mm (0.72) and to the number of retrieved and mature oocytes (ρ 0.82/0.77, respectively), whereas serum E2 is moderately correlated to the parameters mentioned above (ρ 0.64/0.69/0.69, respectively). With an area under the curve (AUC) of 0.91 for Inhibin A, compared to an AUC of 0.84 for E2, Inhibin A can be regarded as a better predictor for the optimal timing of trigger medication with a threshold number of ≥10 mature oocytes. It can be concluded from this data that serum Inhibin A in combination with transvaginal ultrasound monitoring may be a more powerful tool in the decision making process on trigger timing as compared to E2.


Biomarkers/metabolism , Fertilization in Vitro/methods , In Vitro Oocyte Maturation Techniques/methods , Inhibins/metabolism , Oocytes/cytology , Oogenesis , Ovulation Induction/methods , Sperm Injections, Intracytoplasmic/methods , Adult , Cross-Sectional Studies , Female , Humans , Inhibins/genetics , Oocytes/metabolism , Prospective Studies
4.
Fertil Steril ; 113(4): 876-884.e2, 2020 04.
Article En | MEDLINE | ID: mdl-32147175

OBJECTIVE: To examine whether accounting for a woman's age and body mass index (BMI) would improve the ability of antimüllerian hormone (AMH) to distinguish between women with (cases) and without (controls) polycystic ovarian syndrome (PCOS). DESIGN: An opportunistic case-control dataset of reproductive age women having evaluations for PCOS as defined by National Institutes of Health criteria. SETTING: Two medical centers in the United States enrolled women. Serum samples were analyzed for relevant analytes. PATIENTS: Women were between 18 and 39 years of age when samples and clinical information were collected. Residual samples had been stored for 2-17 years. AMH was measured via immunoassay. INTERVENTIONS: None; this was an observational study. MAIN OUTCOME MEASURES: Detection and false-positive rates for PCOS were computed for AMH results expressed as multiples of the median (MoM) both before and after adjustment for the woman's age and BMI. RESULTS: Using unadjusted AMH MoM results, 168 cases (78%) cases were at or beyond the 90th centile of controls (2.47 MoM). After accounting for each woman's age and BMI, 188 (87%) of those women were beyond the 90th centile of controls (2.20 MoM), a significant increase (P = .015). The adjusted AMH MoM levels fitted logarithmic normal distributions well (mean, standard deviation for controls and cases of 0.0000, 0.2765 and 0.6884, 0.2874, respectively) and this allowed for computation of patient-specific PCOS risks. CONCLUSIONS: Accounting for the woman's age and BMI resulted in significantly higher AMH-based detection rates for PCOS at a 10% false-positive rate, and patient-specific PCOS risks could be computed.


Anti-Mullerian Hormone/blood , Body Mass Index , Polycystic Ovary Syndrome/blood , Polycystic Ovary Syndrome/diagnosis , Adolescent , Adult , Age Factors , Biomarkers/blood , Case-Control Studies , Female , Humans , Young Adult
5.
Endocr Pract ; 26(3): 318-327, 2020 Mar.
Article En | MEDLINE | ID: mdl-31859547

Objective: Preeclampsia is a common disorder of pregnancy, causing significant morbidity and mortality for mothers and infants. Several molecules, including glycosylated fibronectin (GlyFn), the inhibin-related proteins, anti-müllerian hormone (AMH), and the insulin-like growth factor axis, are altered in maternal plasma in the setting of preeclampsia; however, these molecules have not been previously measured in cord blood of infants born to mothers with preeclampsia, which may represent changes in fetal physiology. We evaluated potential biomarkers of preeclampsia in umbilical cord blood to fill the gap in knowledge. Methods: This is a case-control study of 196 neonates born at a tertiary teaching hospital in Boston from 2010-2017. Forty-nine neonates born to mothers with preeclampsia were matched 1:3 by gestational age, sex, and birth weight z-score with 147 controls. Eleven analytes were measured in cord blood by enzyme-linked immunosorbent assay. Binary logistic regression analyses were performed to evaluate associations between preeclampsia and analytes. Results: Mean cord blood levels of GlyFn and total inhibin were significantly lower in neonates born to mothers with preeclampsia compared to controls, and AMH levels were significantly higher in males born to mothers with preeclampsia than male controls. Associations remained significant after controlling for maternal and neonatal characteristics. Conclusion: Cord blood levels of GlyFn and inhibin are decreased and AMH (male) levels are increased in infants of preeclamptic mothers, which is opposite the pattern these biomarkers show in serum of mothers with preeclampsia. These molecules may be important in the pathophysiology and long-term effects of preeclampsia on the developing fetus. Abbreviations: AMH = anti-müllerian hormone; ELISA = enzyme-linked immunosorbent assay; GlyFn = glycosylated fibronectin; IGF = insulin-like growth factor; IGFBP5 = insulin-like growth factor binding protein 5; LOD = limit of detection; PAPP-A = pregnancy-associated plasma protein A; PAPP-A2 = pregnancy-associated plasma protein A2.


Pre-Eclampsia , Anti-Mullerian Hormone , Boston , Case-Control Studies , Female , Fetal Blood , Fibronectins , Glycation End Products, Advanced , Humans , Infant, Newborn , Inhibins , Male , Mothers , Pregnancy
6.
Metabolism ; 100: 153959, 2019 11.
Article En | MEDLINE | ID: mdl-31401027

BACKGROUND: A newborn's birth weight for gestational age provides important insights into his or her fetal growth and well-being. While the underlying mechanisms regulating fetal growth remain to be fully elucidated, the IGF axis plays an important role. Some components of this axis have been well-characterized in umbilical cord blood, but others have not yet been studied. We measured the proteases PAPP-A and PAPP-A2, the binding proteins they cleave (IGFBP-4 and -5), and the established molecules IGF-I and -II in umbilical cord blood to better characterize the IGF axis in relation to birth weight and length. METHODS: We performed a case-control study of 180 neonates born at a tertiary teaching hospital in Boston. To maximize power, infants were recruited in a 1:3:1 ratio with 37 SGA, 111 AGA, and 37 LGA infants matched by gestational age, sex, and delivery mode. IGF-I, IGF-II, IGFBP-4, IGFBP-5, PAPP-A, and PAPP-A2 were measured in umbilical cord blood by ELISA. Associations between birth weight and birth length Z-scores and the Z-scores of the above molecules were analyzed using linear regression models and analysis of covariance. RESULTS: Birth weight and length Z-scores were positively associated with Z-scores of IGF-I, IGF-II, total IGFBP-4, and IGFBP-5, with IGF-I having the strongest association. Birth weight and length Z-scores were negatively associated with Z-scores of intact IGFBP-4, PAPP-A, and PAPP-A2 levels. CONCLUSIONS: We confirm previous findings of significant associations between the IGFs in cord blood and newborn size and for the first time show positive associations between cord blood total IGFBP-4 and -5 and birth weight and a negative association between intact IGFBP-4 and birth weight. We also show for the first time a reciprocal relationship between cord blood levels of PAPP-A and PAPP-A2 and newborn size. The implications of these findings need to be further examined in large longitudinal studies and likely have diagnostic and therapeutic potential.


Insulin-Like Growth Factor Binding Protein 4/metabolism , Insulin-Like Growth Factor Binding Protein 5/metabolism , Insulin-Like Growth Factor II/metabolism , Insulin-Like Growth Factor I/metabolism , Isoenzymes/metabolism , Placenta/enzymology , Pregnancy-Associated Plasma Protein-A/metabolism , Case-Control Studies , Female , Humans , Infant, Newborn , Isoenzymes/chemistry , Pregnancy , Pregnancy-Associated Plasma Protein-A/chemistry , Protein Binding , Proteolysis
7.
Theriogenology ; 86(6): 1467-1474, 2016 Oct 01.
Article En | MEDLINE | ID: mdl-27291082

In the veterinary practice, there is a need for a diagnostic tool to check the gonadal status in female dogs because it may be difficult to determine whether a female animal has been spayed or whether there are ovarian remnants. Although less prevalent, a similar situation pertains to male dogs. Anti-Müllerian hormone (AMH) is an important regulator of gonadal function and is a specific gonadal product that can be determined in circulation. The objective of this study was to develop and test a canine blood AMH assay as a diagnostic tool to determine the presence of functional gonadal tissue in dogs. A prospective study with a training-validation set paradigm was used. A canine AMH assay was developed and serum and plasma AMH concentrations were determined in blood samples from 46 intact female dogs, 48 spayed females, 50 intact males, and 48 castrated males collected at two separate institutes. Using a training-validation set paradigm, it was found that using cutoff values of 1.1 ng/mL (female) and 5.5 ng/mL (male) AMH, the assay reported excellent specificity and sensitivity of 100% and 90% in female dogs, and good specificity and sensitivity of 100% and 76%, in male dogs, respectively. The sensitivity in male dogs could be further enhanced by including a serum testosterone determination. This newly developed canine AMH assay is a valuable diagnostic tool to determine gonadal status in veterinary medicine.


Anti-Mullerian Hormone/blood , Dogs , Orchiectomy/veterinary , Ovariectomy/veterinary , Animals , Female , Male , Ovary/physiology , Prospective Studies , Reference Values , Sensitivity and Specificity , Testis/physiology
8.
Fertil Steril ; 106(1): 50-55, 2016 07.
Article En | MEDLINE | ID: mdl-27042970

OBJECTIVE: To investigate for differences in reproductive hormone levels in male relatives of women with polycystic ovary syndrome (PCOS). DESIGN: Cross-sectional study. SETTING: Academic medical center. PATIENT(S): Sixty-three fathers and 66 brothers of women with PCOS as well as two groups of control men of comparable age to fathers (older control, n = 30) and brothers (younger control, n = 58). INTERVENTION(S): A single early morning fasting blood sample was obtained for the measurement of reproductive hormone levels. MAIN OUTCOME MEASURE(S): Testosterone, LH, FSH, antimüllerian hormone (AMH), inhibin B, estradiol (E2), and estrone (E1) levels were measured. RESULT(S): The AMH, LH, and FSH levels were significantly increased in male relatives compared with their respective control groups. The levels of E2, E1, T, and inhibin B did not differ between the groups. CONCLUSION(S): The AMH, LH, and FSH levels were increased in adult male relatives of women with PCOS, suggesting that they may have altered testicular function and changes in neuroendocrine regulation of gonadotropin secretion. These changes may reflect effects of PCOS susceptibility genes such as the recently mapped chromosome 11p14.1 locus in the region of the FSH B polypeptide gene.


Anti-Mullerian Hormone/blood , Fathers , Polycystic Ovary Syndrome/genetics , Reproduction/genetics , Siblings , Academic Medical Centers , Adolescent , Adult , Aged , Biomarkers/blood , Case-Control Studies , Cross-Sectional Studies , Female , Follicle Stimulating Hormone, Human/blood , Humans , Luteinizing Hormone/blood , Male , Middle Aged , Polycystic Ovary Syndrome/diagnosis , Polycystic Ovary Syndrome/physiopathology , Reproductive Health , Up-Regulation , Young Adult
9.
Oncotarget ; 5(4): 1014-25, 2014 Feb 28.
Article En | MEDLINE | ID: mdl-24572990

The insulin-like growth factor (IGF) signaling pathway is involved in certain human cancers, and the feasibility of directly targeting the IGF receptor has been actively investigated. However, recent evidence from clinical trials suggests that this approach can be problematic. We have developed an alternative strategy to indirectly inhibit the IGF signaling by targeting the metalloproteinase, pregnancy-associated plasma protein-A (PAPP-A). PAPP-A associated with the cell surface cleaves IGF binding protein-4 (IGFBP-4), when IGF is bound to IGFBP-4, and thereby increases IGF bioavailability for receptor activation in an autocrine/paracrine manner. We hypothesized that inhibition of PAPP-A would suppress excessive local IGF signaling in tissues where this is caused by increased PAPP-A proteolytic activity. To test this hypothesis, we developed an inhibitory monoclonal antibody, mAb 1/41, which targets a unique substrate-binding exosite of PAPP-A. This inhibitor selectively and specifically inhibits proteolytic cleavage of IGFBP-4 with an inhibitory constant (Ki) of 135 pM. In addition, it inhibited intracellular signaling of the IGF receptor (AKT phosphorylation) in monolayers of A549 cells, an IGF-responsive lung cancer-derived cell line found to express high levels of PAPP-A. We further showed that mAb 1/41 is effective towards PAPP-A bound to cell surfaces, and that it is capable of inhibiting PAPP-A activity in vivo. Using a murine xenograft model of A549 cells, we demonstrated that mAb 1/41 administered intraperitoneally significantly inhibited tumor growth. Analysis of xenograft tumor tissue recovered from treated mice showed penetration of mAb 1/41, reduced IGFBP-4 proteolysis, and reduced AKT phosphorylation. Our study provides proof of concept that IGF signaling can be selectively reduced by targeting a regulatory proteinase that functions extracellularly, upstream of the IGF receptor. PAPP-A targeting thus represents an alternative therapeutic strategy for inhibiting IGF receptor signaling.


Antibodies, Monoclonal/pharmacology , Lung Neoplasms/drug therapy , Lung Neoplasms/metabolism , Pregnancy-Associated Plasma Protein-A/antagonists & inhibitors , Receptors, Somatomedin/metabolism , Animals , Antibodies, Monoclonal/immunology , Disease Models, Animal , Female , HEK293 Cells , Heterografts , Humans , Insulin-Like Growth Factor I/metabolism , Lung Neoplasms/enzymology , Male , Mice , Mice, Knockout , Molecular Targeted Therapy , Pregnancy , Pregnancy-Associated Plasma Protein-A/immunology , Pregnancy-Associated Plasma Protein-A/pharmacology , Signal Transduction , Transfection , Xenograft Model Antitumor Assays
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