Risk Factors for Hypogonadism in Male Patients with Type 2 Diabetes

A Novel Immunodeficient Hyperglycemic Mouse Carrying the Ins1 Akita Mutation for Xenogeneic Islet Cell Transplantation

BACKGROUND

For patients who have difficulty controlling blood glucose even with insulin administration, xenogeneic islet cells, including human stem cell-derived pancreatic islets (hSC-islet) and porcine islets, have garnered attention as potential solutions to challenges associated with donor shortages. For the development of diabetes treatment modalities that use cell transplantation therapy, it is essential to evaluate the efficacy and safety of transplanted cells using experimental animals over the long term.

METHODS

We developed permanent diabetic immune-deficient mice by introducing the Akita (C96Y) mutation into the rodent-specific Insulin1 gene of NOD/Shi-scid IL2rγc null (NOG) mice ( Ins1 C96Y/C96Y NOG). Their body weight, nonfasting blood glucose, and survival were measured from 4 wk of age. Insulin sensitivity was assessed via tolerance tests. To elucidate the utility of these mice in xenotransplantation experiments, we transplanted hSC-islet cells or porcine islets under the kidney capsules of these mice.

RESULTS

All male and female homozygous mice exhibited persistent severe hyperglycemia associated with β-cell depletion as early as 4 wk of age and exhibited normal insulin sensitivity. These mice could be stably engrafted with hSC-islets, and the mice that received porcine islet grafts promptly exhibited lowered blood glucose levels, maintaining blood glucose levels below the normal glucose range for at least 52 wk posttransplantation.

CONCLUSIONS

The Ins1C96Y/C96Y NOG mouse model provides an effective platform to assess both the efficacy and safety of long-term xenograft engraftment without the interference of their immune responses. This study is expected to contribute essential basic information for the clinical application of islet cell transplantation.

Combined obesity- and lipid-related indices are associated with hypogonadism in Chinese male patients with type 2 diabetes: a cross-sectional study

Background

There is insufficient attention to hypogonadism in Chinese males with type 2 diabetes mellitus (T2DM). We evaluated the relationship between Combined obesity- and lipid-related indices [Visceral Adiposity Index (VAI), Chinese Visceral Adiposity Index (CVAI), Triglyceride Glucose Index (TyG) and Lipid Accumulation Product (LAP)] with total testosterone (TT) and analyzed the predictive capability of the respective cut-off values.

Methods

We recruited 958 hospitalized male patients with T2DM at the Affiliated Hospital of Qingdao University, collected baseline data and four calculated indices, and obtained their dominance ratio (OR) and corresponding 95% confidence intervals (CI) with TT by multivariate logistic regression. Receiver operating characteristic (ROC) curves were then used to determine cutoff values in predicting hypogonadism (TT< 12 nmol/L), and we also analyzed the combinations between the different indices.

Results

VAI, CVAI, TyG, and LAP all have satisfactory predictive capabilities. The test capability (sensitivity and specificity) of all four indices was better or not worse than that of body mass index (BMI), homeostasis model assessment of insulin resistance (HOMA-IR) and waist circumference (WC). All four indices were effective predictors of hypogonadism at their respective cutoff values (VAI ≥ 2.284, CVAI ≥ 145.779, TyG ≥ 4.308, and LAP ≥ 59.850). Of these, LAP had the largest area under the curve (AUC, AUC = 0.852, Std. Error = 0.014, 95% CI = 0.818-0.873). However, the predictive capability of the combined indices was not significantly improved over the individual indices.

Conclusions

VAI, CVAI, TyG, and LAP are sensitive indices for predicting hypogonadism in Chinese male patients with T2DM. Considering the need for concise and accurate indices in clinical practice, we suggest LAP as a commonly used index.

Testosterone deficiency in non-obese type 2 diabetic male patients

BACKGROUND AND AIMS

it is unclear whether male hypogonadism is ascribable to the diabetic state per se, or because of other factors, such as obesity or age. We aimed to investigate the prevalence and identify the predictors for testosterone deficiency among non-obese type 2 diabetic males.

METHODS

This cross-sectional study was conducted on 95 nonobese type 2 diabetic males with BMI below 30. We evaluated the total testosterone (TT) levels to determine prevalence and risk factors of testosterone deficiency. Serum TT ≤ 300 ng/dl defined testosterone deficiency.

RESULTS

The prevalence of testosterone deficiency was 29.1%. Testosterone deficient patients had statistically significantly higher visceral adiposity index (VAI), waist, and triglyceride in comparison with normal testosterone patients. TT level correlated with VAI, waist, BMI, LH, and age. VAI was the only significant predictor of TT levels even after adjustment for age and BMI in regression analysis. Furthermore, VAI was a statistically significant risk factor for testosterone deficiency in binary logistic analysis.

CONCLUSIONS

testosterone deficient non-obese type 2 diabetic male patients had elevated VAI, waist, and triglyceride. Moreover, elevated VAI was a risk factor for testosterone deficiency. VAI could be an easily applicable and reliable index for the evaluation and prediction in type 2 non-obese diabetic males.

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.

Correlation between reproductive hormones levels and semen quality in patients with diabetes

Diabetes mellitus (DM) is rarely sought among infertile patients due to a lack of studies and inconsistency regarding its impact on semen quality. This cross-sectional study aimed to determine the influence of T2DM on the pituitary gland hormones (FSH and LH) in males. A total of 60 participants participated in this study, of which 35 were diagnosed with diabetes mellitus, and 25 were without diabetes. Fasting blood sugar, HbA1c, LH, FSH, TT, E2, and prolactin were tested. Diabetic men had lower serum LH, FSH, and TT levels than non-diabetics and higher prolactin and E2 levels. According to the semen examination, including sperm count, PH, motility, and morphology, diabetic patients had considerably lower sperm counts, motility, and morphology than non-diabetic patients. In conclusion, the decrease in the concentration of reproductive hormones in diabetic patients leads to sexual weakness, resulting in abnormal seminal fluid parameters, which are below the normal levels than in apparently healthy persons.

Gaps in the management of diabetes in Asia: A need for improved awareness and strategies in men's sexual health

Sexual dysfunction, which is defined as 'difficulty during any stage of the sexual encounter that prevents or impairs the individual or couple from enjoying sexual activity', is globally prevalent in males with prediabetes and diabetes. It is an early harbinger of cardiovascular diseases and has a profound impact on one's physical, mental, and social health. Among patients with either prediabetes or diabetes, the most common male sexual dysfunctions are hypogonadism, erectile dysfunction, and premature ejaculation. In Asia, although sexual health is an important factor of men's health, it is rarely discussed freely in real-life practice. Addressing sexual health in Asian males has always been challenging with multiple barriers at the levels of patients and health care providers. Therefore, the assessment and management of sexual dysfunction in routine clinical practice should involve a holistic approach with effective patient-provider communication. In this review, we discuss the epidemiology, pathophysiology, and the management of hypogonadism, erectile dysfunction, and premature ejaculation among males with either prediabetes or diabetes (type 1 and type 2), as well as the evidence gaps across Asia.

Glycemic Variability in Subjects with Diabetes and Hypogonadism during Testosterone Replacement Treatment: A Pilot Study

Background: This is a proof of concept, as a pilot study, with the aim to evaluate continuous glucose monitoring metrics (CGM) in subjects with type 2 diabetes (T2DM), treated with nutritional therapy and metformin, before and after testosterone replacement therapy (TRT). Methods: In this longitudinal observational study, subjects affected by T2DM and starting TRT for documented ED and hypogonadism were enrolled. All subjects mounted a CGM system during the v0 visit, one week before the beginning of the TRT (week−1), during v2, four weeks after the start of TRT (week 4), and v4 (week 12). CGM was worn for about 144 h after each visit. Results: A total of seven patients, referring to our clinic for erectile dysfunction (ED), were studied (aged 63.3 ± 2.3 years). Mean (± standard deviation) total testosterone level was 2.3 ± 0.6 ng/mL at baseline. After TRT, total testosterone level was 4.6 ± 3.04 ng/mL at week 4 and 3.93 ± 4.67 ng/mL at week 12. No significant differences were observed in TIR, TAR, TBR, estimated HbA1c, AUC below, and AUC above limit during the intervention period. Conclusions: This is the first study evaluating the effects of TRT on daily glucose excursions in subjects with T2DM and hypogonadism. Though we did not find any significant difference in key CGM metrics during the 12 weeks of TRT, this study confirms the glycometabolic safety of the TRT even on the most novel standardized glycemic targets.

Overt hypogonadism is a cardiovascular risk factor in type 2 diabetic males: An observational study

We aimed to evaluate the effects of hypogonadism on metabolic and chronic complications in type 2 diabetic males. 261 nonobese males with type 2 diabetes aged 18-70 were involved in the study. Hypononadal males were divided into 2 groups as overt hypogonadism (total testosterone≤230 ng/dl) and borderline hypogonadism (230-345 ng/dl). The control group involved eugonadal diabetic males. Micro-macrovascular complications were recorded. 101 patients had hypogonadism (38.7%), and 160 patients were eugonadal (61.3%). Microvascular complication rate was not different, but macrovascular complication rate was significantly higher in hypogonadal males (42.6%/31.3%, p = 0.042). Optimal glycosylated haemoglobin (HbA1c) achievement(<7%) was significantly lower in hypogonadal patients (20.8%/31.3%, p = 0.043). Poor glycaemic control (HbA1c≥7%), presence of microvascular complication and increased triglyceride levels were independent risk factors for hypogonadism (OR: 1.5, p = 0.044;OR:3.89,p = 0.025 and OR: 1.0, p = 0.016 respectively). Overt hypogonadism, hypertension, hypercholesterolaemia and severe hypoglycaemia were independent risk factors for macrovascular complications (OR: 1.0, p = 0.027; OR:2.6, p = 0.002; OR: 1.8, p = 0.047 and OR: 1.0, p = 0.007 respectively), diabetes duration (≥5 years) and poor glycaemic control for microvascular complication (OR: 1.0, p = 0.031 and OR:2.0, p = 0.028). As a result, hypogonadism is frequent among diabetic males and poor glycaemic control may be an important contributing factor. Furthermore overt hypogonadism is an important cardiovascular risk marker. Therefore, ensuring eugonadism in diabetic patients may positively affect both glycaemic control and complications.

Clinical and biochemical correlates of hypogonadism in men with type 2 diabetes mellitus

Introduction

there is an association between hypogonadism and obesity, chronic hyperglycaemia, and ageing in men with type 2 diabetes mellitus (T2DM). T2DM is known to be associated with low testosterone. There is a paucity of data on the risk factors of hypogonadism in Nigerian men with T2DM. The objective of this study was to determine the clinical and biochemical correlates of hypogonadism and clinical predictors of low total testosterone levels in men with T2DM.

Methods

this was a cross-sectional study consisting of 358 men with T2DM and 179 non-diabetic men (controls). Structured Androgen Deficiency in the Ageing Male questionnaire was administered. Clinical and biochemical parameters were measured. Free testosterone was calculated from albumin, SHBG and total testosterone using Vermeulen´s method. Hypogonadism was defined as fasting TT as < 8 nmol/L with or without symptoms or TT of 8-12 nmol/L with symptoms of androgen deficiency. Low testosterone was defined as serum total testosterone levels ≤ 12 nmol/L.

Results

the mean (±SD) total testosterone of men with T2DM and controls were 8.79±3.35 nmol/L and 15.41±3.79 nmol/L respectively (p < 0.001). The risk of hypogonadism was associated with central obesity (Odds ratio [OR] 2.24, 95% confidence interval [CI] 0.38-13.07), systolic hypertension (OR 3.93, 95% CI 0.67-23.10), hyperglycaemia (OR 2.48, 95% CI 0.37-16.46) and hypercholesterolaemia (OR 2.50, 95% CI 0.43-14.61). In a multivariable regression analysis, there was a significant negative correlation between total testosterone and triglycerides (r -1.85, 95% CI -3.58 - 0.12, P = 0.04) and HDL cholesterol (r -1.25, 95% CI -5.95-3.45, P = 0.02).

Conclusion

this study shows that in men with T2DM, triglycerides and HDL cholesterol are independent correlates of hypogonadism but not central adiposity, systolic blood pressure and glycaemia. Further large prospective studies are recommended.

Secondary male hypogonadism: A prevalent but overlooked comorbidity of obesity

Male hypogonadism associated with obesity is a very prevalent condition and is increasing in parallel with the epidemic prevalence of obesity. Low testosterone levels promote higher fat mass with reduced lean mass. Male hypogonadism is related to an increase in associated cardiometabolic complications, such as hypertension, type 2 diabetes mellitus, the metabolic syndrome, and cardiovascular disease. Its influence as a comorbidity of obesity is becoming more evident and should be evaluated and treated in at-risk patients. Mechanisms involved in this relationship include body composition changes, the presence of adipokines, insulin resistance, and other factors, some of which are still unknown. Weight loss and treatment to replace testosterone levels improve the metabolic profile and quality of life in patients with obesity and hypogonadism; these beneficial effects depend on treatment modality and duration of therapy. The use of testosterone replacement therapy may be indicated, as it has not been shown to increase cardiovascular risk, and retrospective studies suggest a reduction in events in men with metabolic syndrome and type 2 diabetes.

Comparison of Anthropometric Measures for Evaluating the Association Between Hypogonadism and Hypothalamic-Pituitary-Gonadal Hormones in a Taiwanese Population

To investigate the degree of association between levels of sex hormones and anthropometric indices in male population. A cross-sectional survey was conducted between July 2014 and July, 2016, in a men's health polyclinic in Taiwan. Body mass index, waist circumference, waist-to-height ratio (WHtR), and conicity index were tested. Serum total testosterone, free testosterone, and dehydroepiandrosterone sulfate (DHEA-S) were measured. Decreased testosterone levels were correlated with the four indices (r = -0.09 to -0.27, p < 0.01). In hypogonadism group, DHEA-S deficiency was associated with older age, higher anthropometric indices, and chronic illness. The areas under the receiver operating characteristic curves of hypogonadism and DHEA-S deficiency by the four anthropometric indices ranged from 52.5% to 65.9%. Logistic regression analysis revealed that obesity, defined by the four indices, was associated with increased risk of hypogonadism. Moreover, obesity was also associated with increased risk and DHEA-S deficiency. Anthropometric indices analyzed are associated with lower testosterone and DEAH-S deficiency. A WHtR of 0.5 is suggested to be a simple and reliable indicator of hypogonadism and DHEA-S deficiency.

Assessment of Hypogonadism in Men With Type 2 Diabetes: A Cross-Sectional Study From Saudi Arabia

BACKGROUND/OBJECTIVES

A high incidence of hypogonadism in men with type 2 diabetes (T2D) has been globally reported. This study aimed to determining the frequency of hypogonadism and related risk factors among men with T2D in a single-site hospital in Saudi Arabia.

DESIGN AND METHODS

A cross-sectional study was performed on 157 men with T2D (between 30 and 70 years of age). Using a prestructured questionnaire, the demographic features of these patients were gathered and their medical records were referred to gather information regarding the duration of the diabetes, smoking habits, and the presence of retinopathy, neuropathy, and nephropathy. Besides these, the biochemical parameters, total testosterone (TT), free testosterone, sex hormone-binding globulin, follicle-stimulating hormone, luteinizing hormone, prolactin, serum lipids, and glycosylated hemoglobin were also recorded. All the patients submitted the fully completed Androgen Deficiency in Aging Male (ADAM) questionnaire. The combination of symptoms (positive ADAM score) plus a TT level ⩽8 nmol/L constituted the condition of hypogonadism.

RESULTS

The total frequency of hypogonadism was 22.9% (36/157). Of the 157 total patients, 123 (78.3%) were shown to be ADAM positive, and of these, 90 (73.2%) exhibited decreased libido, 116 (94.3%) had weak erections, and 99 (80.5%) reported more than 3 symptoms of ADAM. Of these hypogonadic patients, 22.2% (n = 8) revealed primary hypogonadism, whereas 77.8% (n = 28) showed secondary hypogonadism. From the univariate analysis conducted, significant relationship was observed between treatment type, body mass index (BMI), and hypogonadism. The regression analysis showed BMI acting an independent risk factor of hypogonadism.

CONCLUSIONS

Saudi men with T2D revealed a high incidence of hypogonadism. Body mass index was identified as an independent risk factor for hypogonadism.

Effects of Betulinic Acid on the Male Reproductive System of a Streptozotocin-Nicotinamide-Induced Diabetic Mouse Model

Purpose

The present study was conducted to evaluate the favorable or harmful effects of betulinic acid (BA) on a diabetic reproductive system.

Materials and Methods

In this experimental study, 60 male Naval Medical Research Institute mice (20∼25 g) were randomly divided into 6 groups: control, diabetes, diabetes+BA (10, 20, and 40 mg/kg), and diabetes+ metformin (200 mg/kg). A diabetic model was induced by a single dose of streptozotocin (STZ) (65 mg/kg) injection intraperitoneally 15 minutes after an intraperitoneal administration of nicotinamide (NA) (120 mg/kg). BA and metformin were gavaged for 2 weeks after confirmed diabetes induction in the treatment groups. One day after the last treatment, plasma luteinizing hormone (LH), follicle-stimulating hormone (FSH), and testosterone levels were evaluated. The cauda epididymis and testis were removed to analyze the sperm count and testis histopathology.

Results

LH levels increased in diabetic (p<0.001) and diabetic BA-treated mice (p=0.009). Plasma levels of testosterone (p< 0.001) and sperm count (p=0.04) decreased in these groups when compared to the control group. Furthermore, administration of 10 mg/kg (p=0.001), 20 mg/kg (p=0.004), or 40 mg/kg (p<0.001) of BA led to a greater reduction in plasma testosterone levels compared to the diabetes group. Seminiferous tubule vacuole numbers increased in diabetic and diabetic BA-treated mice, but testis morphology and FSH level assessment revealed no significant differences between the groups.

Conclusions

STZ-NA can induce diabetic alterations in the male reproductive system and the administration of BA in diabetic treated mice resulted in a worse outcome.