Anti-Mullerian Hormone and Inhibin B Levels in Obese Boys; Relations with Cardiovascular Risk Factors

AMH in Males: Effects of Body Size and Composition on Serum AMH Levels

Serum concentrations of anti-Müllerian hormone (AMH) have been found to decrease with increasing body mass index (BMI) in many studies. It is not yet clear whether this stems from an adverse effect of adiposity on AMH production, or from dilution due to the greater blood volume that accompanies a larger body size. To investigate a possible hemodilution effect, we explored the relationships between serum AMH levels and different parameters of body composition using linear regression models in a cohort of adult males. Body weight, lean mass (LM), and body surface area (BSA) were found to be better predictors of AMH than measures of adiposity, such as BMI or fat mass. Since both LM and BSA correlate with plasma volume better than adipose tissue, we conclude that hemodilution of AMH does occur in adult males and should be considered for normalization in future studies.

Testicular volume in 268 children and adolescents followed-up for childhood obesity-a retrospective cross-sectional study

CONTEXT

Prevalence of obesity in childhood has increased over the past few decades. The impact of obesity and of obesity-related metabolic disorders on testicular growth is unknown.

OBJECTIVE

To evaluate the impact of obesity, hyperinsulinemia, and insulin resistance on testicular volume (TV) in pre-pubertal (<9 years), peri-pubertal (9-14 years), and post-pubertal (14-16 years) periods.

METHODS

We collected data on TV, age, standard deviation score (SDS) of the body mass index (BMI), insulin, and fasting glycemia in 268 children and adolescents followed-up for weight control.

RESULTS

Peri-pubertal boys with normal weight had a significantly higher TV compared to those with overweight or obesity. No difference was found in the other age ranges when data were grouped according to BMI. Pre- and post-pubertal children/adolescents with normal insulin levels had significantly higher TV compared to those with hyperinsulinemia. Peri-pubertal boys with hyperinsulinemia had significantly higher TV compared to those with normal insulin levels. Post-pubertal adolescents with insulin resistance had lower TV and peri-pubertal boys had higher TV compared to those without insulin resistance. No difference was found in pre-puberty.

CONCLUSIONS

Closer control of the body weight and the associated metabolic alterations in childhood and adolescence may maintain testicular function later in life.

The effects of different physiologic concentrations of prolactin in association with reproductive hormones on the incidence of type 2 diabetes mellitus in men: Tehran Lipid and Glucose Study

BACKGROUND

Data is inconsistent and, for the most part, not sufficient to demonstrate the association between serum Prolactin (PRL) concentration within the physiologic range and the incidence rate of type 2 Diabetes Mellitus (DM) among men. Moreover, since both PRL and type 2 DM are associated with reproductive hormones, investigating these hormones might improve our understanding of how PRL might impose its effect on the incidence rate of type 2 DM.

METHODS

For the present study, 652 eligible men aged 29-70 with a normal baseline PRL concentration were selected from the Tehran Lipid and Glucose Study (TLGS). Participants were sub-classified into three groups (tertiles) according to the serum concentration of PRL and were followed for 15.8 years. The incidence of type 2 DM and PRL, LH, FSH, testosterone, and AMH concentrations were measured. The effect of hormonal variables on the incidence of type 2 DM was estimated using the log-binomial model, adjusted for major confounding factors. The correlations between PRL and the indicators of glucose and lipid metabolism and other hormonal variables were also explored.

RESULTS

In the unadjusted model, PRL was not significantly associated with the incidence rate of type 2 DM (RR = 0.98, 95% CI: 0.94 - 1.03). After adjusting for potential confounders, the inverse effect of AMH on the incidence rate of type 2 DM was the only significant association. The analyses also indicated a significant positive association between PRL and LH/FSH ratio (r = 0.1, P = 0.01).

CONCLUSION

No significant association was found between serum PRL concentrations within the physiologic range and the incidence rate of type 2 diabetes mellitus among middle-aged men. Men with higher concentrations of PRL within the physiologic range tended to show higher levels of LH and LH/FSH. AMH was the only variable significantly linked to the incidence rate of type 2 DM in men.

Lower Circulating Sertoli and Leydig Cell Hormone Levels During Puberty in Obese Boys: A Cross-sectional Study

CONTEXT

Alterations in semen characteristics and circulating Sertoli and Leydig cell hormones have been described in obese male adults. Whether hormonal alterations occur before adulthood has not been fully evaluated.

OBJECTIVE

We describe circulating Sertoli and Leydig cell hormone levels in overweight-obese (ow/ob) boys through childhood and adolescence in a cross-sectional study.

METHODS

Monocentric study in the Pediatric Endocrinology Unit of Angers University Hospital. Three hundred and fifty-one obese and overweight boys aged 5-19 years underwent physical examination, dual-energy X-ray absorptiometry for body composition, oral glucose tolerance test on insulin and glucose, and measurements of follicle-stimulating hormone, luteinizing hormone, anti-Müllerian hormone (AMH), inhibin B, testosterone, and estradiol. Hormonal levels were compared with normative data obtained from 652 healthy nonoverweight nonobese boys of similar age or Tanner stage.

RESULTS

Median inhibin B and testosterone levels during puberty were significantly lower in ow/ob than in healthy boys (1) from age >12 years and thereafter for inhibin B, and (2) from age >14 years and thereafter for testosterone. At Tanner stages 4 and 5, 26%, 31%, and 18% of inhibin B, testosterone, and AMH values were below the 5th percentile in ow/ob subjects (P < .01). In multiple regression analyses, estradiol and total bone mineral density Z-score were negative predictors of inhibin B, fat mass percentage was a negative predictor of testosterone, and insulin was a negative predictor of AMH.

CONCLUSION

Lower Sertoli and Leydig cell hormone levels during puberty were observed in the ow/ob boys.

Anti-mullerian hormone attenuates insulin resistance and systemic inflammation in old obese C57BL/6 male mice

Purpose

Epidemiological studies show that Anti-mullerian hormone (AMH) is inversely correlated with age, obesity-related diseases, and all-cause mortality in men. To further investigate the role of AMH in aging and obesity, we studied the effect of AMH treatment on the inflammatory and metabolic parameters and weight in old male C57BL/6 mice.

Method

Thirty-six old male C57BL/6 mice (18 month-old) were either on the High-Fat Diet (HFD) or Normal Diet (ND). When obesity occurred in the HFD group, each group was divided into two subgroups; AMH-treated (ND^+AMH and HFD^+AMH) or controls (ND and HFD). The AMH subgroup received 15 ng/gbw of recombinant AMH injection every 48 h in four weeks. Then, serum AMH, CRP, fasting glucose, fasting insulin, and HOMA-IR were measured and analyzed.

Results

AMH injection decreased CRP level (HFD =622.86±25.73, HFD^+AMH =543.2±24.99 ng/ml, p= 0.003), fasting insulin (HFD=1.50± 0.34, HFD^+AMH =0.8±0.25 ng/ml, p=0.006) and HOMA-IR (HFD=12.76± 2.88, HFD^+AMH =7.06±2.31, p=0.008) in the obese old mice comparison with control. In ND group, just CRP levels dropped following AMH injection (ND=451.24±20.61, ND^+AMH= 326.8±23.76 ng/ml; p=0.001). Accelerated weight gain was observed in HFD^+AMH compared with the HFD subgroup (p<0.05).

Conclusions

In conclusion, increasing the circulating level of AMH could subside the systemic inflammation through decreasing CRP levels regardless of diet type and enhance insulin sensitivity in old obese mice. It can also lead to higher weight gain, without inflammation, in old obese male mice who are on an HFD.

The "Hitchhiker's Guide to the Galaxy" of Endothelial Dysfunction Markers in Human Fertility

Endothelial dysfunction is an early event in the pathogenesis of atherosclerosis and represents the first step in the pathogenesis of cardiovascular diseases. The evaluation of endothelial health is fundamental in clinical practice and several direct and indirect markers have been suggested so far to identify any alterations in endothelial homeostasis. Alongside the known endothelial role on vascular health, several pieces of evidence have demonstrated that proper endothelial functioning plays a key role in human fertility and reproduction. Therefore, this state-of-the-art review updates the endothelial health markers discriminating between those available for clinical practice or for research purposes and their application in human fertility. Moreover, new molecules potentially helpful to clarify the link between endothelial and reproductive health are evaluated herein.

Anti-Müllerian hormone levels and risk of type 2 diabetes in women

AIMS/HYPOTHESIS

Given its role in ovarian follicle development, circulating anti-Müllerian hormone (AMH) is considered to be a marker of reproductive ageing. Although accelerated reproductive ageing has been associated with a higher risk of type 2 diabetes, research on the relationship between AMH and type 2 diabetes risk is scarce. Therefore, we aimed to investigate whether age-specific AMH levels and age-related AMH trajectories are associated with type 2 diabetes risk in women.

METHODS

We measured AMH in repeated plasma samples from 3293 female participants (12,460 samples in total), aged 20-59 years at recruitment, from the Doetinchem Cohort Study, a longitudinal study with follow-up visits every 5 years. We calculated age-specific AMH tertiles at baseline to account for the strong AMH-age correlation. Cox proportional hazards models adjusted for confounders were used to assess the association between baseline age-specific AMH tertiles and incident type 2 diabetes. We applied linear mixed models to compare age-related AMH trajectories for women who developed type 2 diabetes with trajectories for women who did not develop diabetes.

RESULTS

During a median follow-up of 20 years, 163 women developed type 2 diabetes. Lower baseline age-specific AMH levels were associated with a higher type 2 diabetes risk (HR_T2vsT3 1.24 [95% CI 0.81, 1.92]; HR_T1vsT3 1.62 [95% CI 1.06, 2.48]; p_trend = 0.02). These findings seem to be supported by predicted AMH trajectories, which suggested that plasma AMH levels were lower at younger ages in women who developed type 2 diabetes compared with women who did not. The trajectories also suggested that AMH levels declined at a slower rate in women who developed type 2 diabetes, although differences in trajectories were not statistically significant.

CONCLUSIONS/INTERPRETATION

We observed that lower age-specific AMH levels were associated with a higher risk of type 2 diabetes in women. Longitudinal analyses did not show clear evidence of differing AMH trajectories between women who developed type 2 diabetes compared with women who did not, possibly because these analyses were underpowered. Further research is needed to investigate whether AMH is part of the biological mechanism explaining the association between reproductive ageing and type 2 diabetes. Graphical abstract.

Effects of Insulin on Porcine Neonatal Sertoli Cell Responsiveness to FSH In Vitro

There is ongoing debate as to whether the decline of sperm production in recent times may be related to a parallel increase in the rate of obesity and diabetes. Lower anti-Müllerian hormone (AMH) and inhibin B secretion have been observed in young hyperinsulinemic patients compared to healthy controls, suggesting a Sertoli cell (SC) dysfunction. The pathophysiological mechanisms underlying SC dysfunction in these patients are poorly understood. To the best of our knowledge, no evidence is available on the effects of insulin on SC function. Therefore, this study was undertaken to assess the effects of insulin on basal and follicle-stimulating hormone (FSH)-stimulated SC function in vitro. To accomplish this, we evaluated the expression of AMH, inhibin B and FSHR genes, the secretion of AMH and inhibin B and the phosphorylation of AKT473 and SC proliferation on neonatal porcine SC after incubation with FSH and/or insulin. We found that similar to FSH, the expression and secretion of AMH is suppressed by insulin. Co-incubation with FSH and insulin decreased AMH secretion significantly more than with FSH alone. Insulin had no effect on the expression and secretion of the inhibin B gene, but co-incubation with FSH and insulin had a lower effect on inhibin B secretion than that found with FSH alone. FSH and/or insulin increased AKT473 phosphorylation and SC proliferation. In conclusion, the results of this study showed that insulin modulates SC function. We hypothesize that hyperinsulinemia may therefore influence testicular function even before puberty begins. Therefore, particular care should be taken to avoid the onset of hyperinsulinemia in children to prevent a future deleterious effect on fertility.

Early Identification of Isolated Sertoli Cell Dysfunction in Prepubertal and Transition Age: Is It Time?

The male transitional phase is of fundamental importance for future fertility. This aspect is largely neglected in clinical practice. This opinion aims to shed light on these issues. The children frequently complete the transition phase with a slight reduction of testicular volume. The system of detecting testicular volume is often inadequate. These patients evidently complete puberty in an incomplete way because they do not reach an adequate testicular volume, albeit in the presence of adequate height and regular secondary sexual characteristics.