Effects of testosterone therapy in adult males with hypogonadism and T2DM: A meta-analysis and systematic review

Mechanisms in endocrinology: hypogonadism and metabolic health in men-novel insights into pathophysiology

Hypogonadism in men is associated with an adverse metabolic phenotype and increased mortality. Reciprocally, obesity and insulin resistance can suppress the hypothalamic-pituitary-gonadal axis in the absence of structural organic disease, further perpetuating a cycle of metabolic dysfunction and low testosterone. The mechanisms underpinning this bidirectional association are complex as hypogonadism is a heterogenous syndrome, and obesity is associated with metabolic perturbations in glucose and lipid metabolism even in the presence of normal testicular function. However, distinct molecular defects specific to testosterone deficiency have been identified in pathways relating to glucose and lipid metabolism in target metabolic depots such as adipose tissue and skeletal muscle. This review discusses the etiology and prevalence of metabolic disease in male hypogonadism, with a specific focus on both disease mechanisms and novel potential approaches to enhance our understanding.

Sex differences and testosterone interfere with the structure of the gut microbiota through the bile acid signaling pathway

Background

The gut microbiome has a significant impact on human wellness, contributing to the emergence and progression of a range of health issues including inflammatory and autoimmune conditions, metabolic disorders, cardiovascular problems, and psychiatric disorders. Notably, clinical observations have revealed that these illnesses can display differences in incidence and presentation between genders. The present study aimed to evaluate whether the composition of gut microbiota is associated with sex-specific differences and to elucidate the mechanism.

Methods

16S-rRNA-sequencing technology, hormone analysis, gut microbiota transplantation, gonadectomy, and hormone treatment were employed to investigate the correlation between the gut microbiome and sex or sex hormones. Meanwhile, genes and proteins involved bile acid signaling pathway were analyzed both in the liver and ileum tissues.

Results

The composition and diversity of the microbiota from the jejunum and feces and the level of sex hormones in the serum differed between the sexes in young and middle-aged Sprague Dawley (SD) rats. However, no similar phenomenon was found in geriatric rats. Interestingly, whether in young, middle-aged, or old rats, the composition of the microbiota and bacterial diversity differed between the jejunum and feces in rats. Gut microbiota transplantation, gonadectomy, and hormone replacement also suggested that hormones, particularly testosterone (T), influenced the composition of the gut microbiota in rats. Meanwhile, the mRNA and protein level of genes involved bile acid signaling pathway (specifically SHP, FXR, CYP7A1, and ASBT) exhibited gender-specific differences, and T may play a significant role in mediating the expression of this pathway.

Conclusion

Sex-specific differences in the structure of the gut microbiota are mediated by T through the bile acid signaling pathway, pointing to potential targets for disease prevention and management techniques by indicating that sex differences and T levels may alter the composition of the gut microbiota via the bile acid signaling pathway.

The impact of sex hormones on metabolic syndrome: univariable and multivariable Mendelian randomization studies

BACKGROUND

Observational studies have found associations between sex hormones and metabolic syndrome(Mets), but the causal relationships remains unclear. This study utilizes univariable and multivariable Mendelian randomization (MR) to elucidate the associations between sex hormones (including sex hormone-binding globulin(SHBG), estradiol(E2), testosterone(T)) and Mets and its subtypes (including waist circumference(WC), fasting blood glucose(FBG), high blood pressure(HBP), high-density lipoprotein(HDL-C), triglycerides(TG)).

METHODS

We utilized summary data from large-scale genome-wide association studies. Univariable Mendelian randomization (UMVMR) analysis was primarily conducted using the inverse variance weighted method (IVW), with secondary analyses employing the weighted median, MR-Egger regression, simple mode method, and weighted mode method. Subsequently, multivariable Mendelian randomization (MVMR) was employed to assess the causal relationships between SHBG, T, E2, and MetS and its components: WC, FPG, HBP, HDL-C, and TG. Sensitivity analyses were conducted to assess result reliability.

RESULTS

Genetically predicted SHBG was significantly negatively associated with MetS (UMVMR: β=-0.72; 95% CI = 0.41 to 0.57; P = 1.28e-17; MVMR: β=-0.60; 95% CI=-0.83 to -0.38; P < 0.001). Positive causal relationships were observed between SHBG and WC(MVMR: β = 0.10; 95% CI = 0.03 to 0.17; P = 0.01) and HDL-C (MVMR: β = 0.41; 95% CI = 0.21 to 0.60; P < 0.001), while negative causal relationships were found between SHBG and HBP (MVMR: β=-0.02; 95% CI=-0.04 to -0.00; P = 0.02), TG (MVMR: β=-0.48; 95% CI=-0.70 to -0.26; P < 0.001). Genetically predicted E2 exhibited a negative association with TG (MVMR: β=-1.49; 95% CI=-2.48 to -0.50; P = 0.003). Genetically predicted T was negatively associated with TG (MVMR: β=-0.36; 95% CI=-0.71 to -0.00; P = 0.049) and WC (MVMR: β=-0.13; 95% CI=-0.24 to -0.02; P = 0.02), with inconsistent sensitivity analyses. Additionally, No other causal associations were found.

CONCLUSION

Our study indicates that SHBG is a protective factor for MetS, potentially delaying its onset and progression through improvements in HBP and TG. Furthermore, T and E2 may improve TG levels, with T also reducing WC levels. Importantly, our study provides new insights for the prevention and treatment of MetS.

Gender Differences in the Incidence of Nephropathy and Changes in Renal Function in Patients with Type 2 Diabetes Mellitus: A Retrospective Cohort Study

Purpose

This research aims to examine and scrutinize gender variations in the incidence of diabetic nephropathy (DN) and the trajectory of renal function in type 2 diabetes mellitus (T2DM) patients.

Patients and Methods

We conducted a retrospective cohort study that enrolled 1549 patients diagnosed with T2DM from May 2015 to July 2023. We separately compared the clinical characteristics of male and female participants with and without DN. We utilized the Kaplan-Meier method to examine the cumulative incidence of DN among T2DM patients of varying genders. Hazard ratios (HR) and 95% confidence intervals (CI) were calculated using univariable and multivariable Cox proportional hazards regression analysis to evaluate the correlation between various factors and the risk of DN incidence. Multiple linear regression was utilized to investigate the relationship between ΔeGFR% and each factor. Logistic regression with cubic spline function and smooth curve fitting was employed to analyze the nonlinear link between ΔeGFR% and the risk of DN among participants of different genders.

Results

The prevalence of DN was higher in female participants (17.31%) than in male participants (12.62%), with a significant cumulative risk ratio (1.33 [1.02-1.73], P = 0.034). Multiple linear regression analysis revealed that creatinine, female gender, blood urea nitrogen, alkaline phosphatase, and total cholesterol had a significant impact on ΔeGFR% in T2DM patients, with standardized β coefficients of -0.325, -0.219, -0.164, -0.084, and 0.071, respectively. The restricted cubic spline analysis demonstrated a strong negative association between ΔeGFR% and the risk of developing DN (P < 0.001).

Conclusion

Both male and female patients with T2DM had a higher prevalence of DN over the 5-year follow-up period. However, women had a greater risk of developing DN and a faster decline in renal function compared to men.

Systematic reviews and meta-analyses on androgen administration in humans: an umbrella review

PURPOSE OF REVIEW

The present umbrella review systematically searches and synthesizes recent (2021-2023) systematic reviews and meta-analyses (SRMA) on androgen administration in humans.

RECENT FINDINGS

Results from 19 SRMA are synthesized. Four themes were identified: market for androgens, prevalence of androgen abuse, psychological effects of androgens, and clinical/therapeutic effects of androgens. One of three androgens on the illicit market are fake or substandard. Whereas one of three androgen users experiences dependence and various serious disorders, only one of three androgen users seeks physician support. Additionally, androgen administration increases self-reported aggression in healthy male individuals, and abuse positively correlates with interpersonal violence. Furthermore, androgen therapy is beneficial in treating persons suffering from various chronic diseases.

SUMMARY

In this umbrella review, we identified 19 SRMA on androgen use and abuse. Results show a high prevalence of fake androgens on the illicit market, a high prevalence of androgen abuse and dependence, and that a huge proportion of androgen users tend to avoid seeking support from clinicians. Also, androgen administration increases self-reported aggression among healthy male, and there is a positive correlation between androgen abuse and violent behavior. Finally, androgens have multiple therapeutic effects on various pathology.

Novel Therapies in Diabetes: A Comprehensive Narrative Review of GLP-1 Receptor Agonists, SGLT2 Inhibitors, and Beyond

Diabetes mellitus, a widespread metabolic illness with increasing global occurrence, continues to have a significant impact on public health. Diabetes is a condition marked by long-term high blood sugar levels. It is caused by a combination of genetic, environmental, and lifestyle factors, which lead to problems with insulin production and insulin resistance. This dysfunctional state disturbs the delicate balance of glucose regulation, promoting the emergence of problems in both large and small blood vessels that have a substantial impact on illness and death rates. Traditional therapy methods have traditionally given more importance to managing blood sugar levels by using insulin sensitizers, secretagogues, and other medications that lower glucose levels. Advancements in our understanding of the underlying mechanisms of diabetes have led to a significant change in approach, focusing on comprehensive therapies that target not only high blood sugar levels but also the accompanying dangers to the heart and kidneys. This study examines the evolving field of diabetes therapies, explicitly highlighting the significance of GLP-1 receptor agonists and SGLT2 inhibitors. These two types of drugs have become essential components in modern diabetes management. GLP-1 receptor agonists replicate the effects of natural glucagon-like peptide-1, leading to insulin production that is reliant on glucose levels, reducing the release of glucagon, and providing cardiovascular advantages that go beyond controlling blood sugar levels. SGLT2 inhibitors, however, act on the process of renal glucose reabsorption, leading to increased excretion of glucose in the urine and showing significant benefits for cardiovascular and renal protection. This extensive investigation seeks to contribute to the ongoing discourse on diabetes therapies by synthesizing existing research. This review aims to provide clinicians, researchers, and policymakers with a comprehensive understanding of the disease background and the specific pharmacological details of GLP-1 receptor agonists, SGLT2 inhibitors, and other related treatments. The goal is to assist them in developing more effective and personalized strategies to tackle the complex challenges presented by diabetes.

Age-Dependent Changes in the Effects of Androgens on Female Metabolic and Body Weight Regulation Systems in Humans and Laboratory Animals

In recent years, the effects of androgens on metabolic and body weight regulation systems and their underlying mechanisms have been gradually revealed in females. In women and experimental animals of reproductive age, androgen excess can adversely affect metabolic functioning, appetite, and body weight regulation. In addition, excess androgens can increase the risk of metabolic disorders, such as obesity, insulin resistance, and diabetes. These unfavorable effects of androgens are induced by alterations in the actions of hypothalamic appetite-regulatory factors, reductions in energy expenditure, insulin resistance in skeletal muscle, and β-cell dysfunction. Interestingly, these unfavorable effects of androgens on metabolic and body-weight regulation systems are neither observed nor evident in ovariectomized animals and post-menopausal women, indicating that the adverse effects of androgens might be dependent on the estrogen milieu. Recent findings may provide novel sex- and age-specific strategies for treating metabolic diseases.

Cardiovascular Complications of Diabetes: From Microvascular to Macrovascular Pathways

Diabetes mellitus, with a growing risk of developing complications, has a significant negative impact on cardiovascular health, including microvascular and macrovascular issues. This thorough narrative study methodically examines the complex connection between cardiovascular problems and diabetes. We start by thoroughly introducing diabetes mellitus, classifying its various forms, and discussing its growing global impact. Then, we examine retinopathy, nephropathy, and neuropathy in detail, illuminating their biology, clinical presentations, and treatment options. Moving on to macrovascular consequences, we investigate the complex relationships between diabetes and coronary artery disease, stroke, and peripheral arterial disease, emphasizing risk factors, diagnostic standards, and treatment plans designed for people with diabetes. The review analyzes the pathophysiological pathways that link diabetes to cardiovascular problems, including endothelial dysfunction, chronic inflammation, immune system dysregulation, and oxidative stress brought on by hyperglycemia. Additionally, we review the critical function of risk monitoring, assessment, and predictive tools in early detection. While highlighting current research paths and the need for tailored medical approaches to address this complex health issue, the story also includes prevention and management strategies, ranging from lifestyle changes to developing medications. This narrative review concludes by providing a thorough summary of current information, highlighting research gaps, and advocating for interdisciplinary efforts to reduce the cardiovascular effects of diabetes.

Diabetes and Prostate Cancer Outcomes in Men with Nonmetastatic Castration-Resistant Prostate Cancer: Results from the SEARCH Cohort

BACKGROUND

The prognosis of diabetic men with advanced prostate cancer is poorly understood and understudied. Hence, we studied associations between diabetes and progression to metastases, prostate cancer-specific mortality (PCSM) and all-cause mortality (ACM) in men with nonmetastatic castration-resistant prostate cancer (nmCRPC).

METHODS

Data from men diagnosed with nmCRPC between 2000 and 2017 at 8 Veterans Affairs Health Care Centers were analyzed using Cox regression to determine HRs and 95% confidence intervals (CI) for associations between diabetes and outcomes. Men with diabetes were classified according to: (i) ICD-9/10 codes only, (ii) two HbA1c values > 6.4% (missing ICD-9/10 codes), and (iii) all diabetic men [(i) and (ii) combined].

RESULTS

Of 976 men (median age: 76 years), 304 (31%) had diabetes at nmCRPC diagnosis, of whom 51% had ICD-9/10 codes. During a median follow-up of 6.5 years, 613 men were diagnosed with metastases, and 482 PCSM and 741 ACM events occurred. In multivariable-adjusted models, ICD-9/10 code-identified diabetes was inversely associated with PCSM (HR, 0.67; 95% CI, 0.48-0.92) while diabetes identified by high HbA1c values (no ICD-9/10 codes) was associated with an increase in ACM (HR, 1.41; 95% CI, 1.16-1.72). Duration of diabetes, prior to CRPC diagnosis was inversely associated with PCSM among men identified by ICD-9/10 codes and/or HbA1c values (HR, 0.93; 95% CI, 0.88-0.98).

CONCLUSIONS

In men with late-stage prostate cancer, ICD-9/10 'code-identified' diabetes is associated with better overall survival than 'undiagnosed' diabetes identified by high HbA1c values only.

IMPACT

Our data suggest that better diabetes detection and management may improve survival in late-stage prostate cancer.

The Bidirectional Link Between Diabetes and Kidney Disease: Mechanisms and Management

The complex and mutually influential connection between diabetes mellitus and chronic kidney disease (CKD) is a significant focal point in the current healthcare landscape. Diabetes, a medical condition characterized by elevated blood glucose levels resulting from impaired insulin action or secretion, has become a significant global epidemic. It poses considerable challenges to healthcare systems and affects millions of individuals worldwide. Concurrently, CKD, characterized by the gradual decline of kidney function, has become a persistent health challenge. This narrative review explores the complex relationship between these two conditions, shedding light on their significant implications for public health, clinical practice, and biomedical research. The correlation between diabetes and kidney disease is not merely coincidental. Diabetes is recognized as a significant risk factor for CKD, as individuals with diabetes are considerably more vulnerable to developing renal complications. Diabetic nephropathy, a distinct type of kidney disease closely associated with diabetes, is a significant factor in developing end-stage renal disease. It is imperative to implement efficient diabetes management strategies to regulate blood sugar levels and prevent potential kidney damage. On the other hand, kidney disease may contribute to the development of diabetes. The kidneys regulate glucose levels by filtering the blood and selectively reabsorbing glucose as necessary. In compromised kidney function, such as CKD, impaired glucose metabolism can give rise to insulin resistance and diabetes. As a result, the management of kidney disease plays a dual role in both preserving renal function and preventing diabetes in individuals who are at risk. The coexistence of diabetes and kidney disease in a patient presents complex clinical challenges. Achieving effective management requires a meticulous balance between glycemic control and preservation of renal function. Failing to maintain this delicate equilibrium can lead to cardiovascular complications and subsequent hospitalizations. This comprehensive narrative review aims to thoroughly examine the pathophysiological mechanisms that connect diabetes and kidney disease. It will provide insights into the clinical manifestations and diagnostic methods, explore various approaches to managing the condition, discuss the crucial role of nutrition, delve into pharmacological interventions, emphasize the importance of patient education and self-care, and shed light on emerging research areas. In addition to impacting individual health outcomes, this reciprocal relationship has significant implications for healthcare systems, socioeconomic landscapes, and public health policy. Comprehending this complex interaction is crucial for making well-informed clinical judgments, improving patient care, and developing a more efficient public health approach to address the interconnected issues of diabetes and kidney disease.

Advances in the Management of Diabetes Mellitus: A Focus on Personalized Medicine

Diabetes mellitus poses a substantial global health challenge, necessitating innovative approaches to improve patient outcomes. Conventional one-size-fits-all treatment strategies have shown limitations in addressing the diverse nature of the disease. In recent years, personalized medicine has emerged as a transformative solution, tailoring treatment plans based on individual genetic makeup, lifestyle factors, and health characteristics. This review highlights the role of genetic screening in predicting diabetes susceptibility and response to treatment, as well as the potential of pharmacogenomics in optimizing medication choices. Moreover, it discusses the incorporation of lifestyle modifications and behavioral interventions to empower patients in their health journey. Telemedicine and remote patient monitoring are also examined for their role in enhancing accessibility and adherence. Ethical considerations and challenges in implementing personalized medicine are addressed. The review envisions a future where personalized medicine becomes a cornerstone in diabetes management, ensuring improved patient outcomes and fostering more effective and patient-centric care on a global scale.

Exploring the Complex Connection Between Diabetes and Cardiovascular Disease: Analyzing Approaches to Mitigate Cardiovascular Risk in Patients With Diabetes

Cardiovascular disease (CVD) is the primary cause of morbidity and mortality in individuals diagnosed with diabetes mellitus. This narrative review offers a comprehensive examination of the complex correlation between diabetes and cardiovascular complications. The objective of this review is to analyze the most recent evidence on preventive measures and treatment options for mitigating cardiovascular risk in patients with diabetes, by synthesizing existing literature. Insulin resistance plays a crucial role in connecting diabetes and CVD, leading to the development of dyslipidemia and atherogenesis. As a result, the risk of cardiovascular events in individuals with diabetes is significantly elevated. Moreover, the presence of hyperglycemia-induced oxidative stress and inflammation serves to intensify endothelial dysfunction and vascular damage, thereby exacerbating the risk of cardiovascular complications. The interaction between diabetes and CVD frequently speeds up the development of atherosclerotic plaque, making the plaque more prone to rupture. This can lead to severe cardiovascular events such as myocardial infarction and stroke. It is crucial to comprehend the intricate relationship between diabetes and CVD in order to formulate effective strategies aimed at enhancing patient outcomes and mitigating the burden associated with these interconnected chronic conditions. Healthcare practitioners can enhance the quality of life and reduce mortality rates associated with CVD in diabetic patients by thoroughly examining evidence-based preventive measures and treatment options. This approach allows them to make informed decisions when managing cardiovascular risk. In summary, this narrative review provides a valuable resource for healthcare professionals and researchers, presenting a comprehensive analysis of the complex relationship between diabetes and CVD. By providing a comprehensive analysis of the latest evidence and elucidating the underlying mechanisms, this review seeks to establish a foundation for the development of innovative strategies in diabetes management. These strategies have the potential to significantly improve cardiovascular outcomes and enhance overall patient care.

Comparative efficacy and safety profile of once-weekly Semaglutide versus once-daily Sitagliptin as an add-on to metformin in patients with type 2 diabetes: a systematic review and meta-analysis

BACKGROUND

The emergence of genetically-modified human proteins and glucagon-like peptide-1 (GLP-1) receptor agonists have presented a promising strategy for effectively managing diabetes. Due to the scarcity of clinical trials focusing on the safety and efficacy of semaglutide as an adjunctive treatment for patients with type 2 diabetes who had inadequate glycemic control with metformin, we conducted a systematic review and meta-analysis. This was necessary to fill the gap and provide a comprehensive assessment of semaglutide compared to sitagliptin, a commonly prescribed DPP-4 inhibitor, in this patient population.

METHODS

A comprehensive and systematic search was carried out on reputable databases including PubMed, the Cochrane Library, and Elsevier's ScienceDirect to identify relevant studies that compared the efficacy of once-weekly Semaglutide with once-daily Sitagliptin in individuals diagnosed with type 2 diabetes mellitus. The analysis of the gathered data was performed utilizing the random-effects model, which considers both within-study and between-study variations.

RESULTS

The meta-analysis incorporated three randomized controlled trials (RCTs), encompassing 2401 participants, with a balanced distribution across the treatment groups. The primary focus of the study revolved around evaluating changes in HbA1C, blood pressure, pulse rate, body weight, waist circumference, and BMI. The findings revealed that once-weekly Semaglutide showed substantially improved HbA1C (WMD: -0.98; 95% CI: -1.28, -0.69, p-value: < 0.0001; I2: 100%), systolic (WMD: -3.73; 95% CI: -5.42, -2.04, p-value: <0.0001; I2: 100%) and diastolic blood pressures (WMD: -0.66; 95% CI: -1.02, -0.29, p-value: 0.0005; I2: 100%), and body weight (WMD: -3.17; 95% CI: -3.84, -2.49, p-value: <0.00001; I2: 100%) compared to once-daily Sitagliptin. However, there was an observed increase in pulse rate (WMD: 3.33; 95% CI: 1.61, 5.06, p-value: <0.00001; I2: 100%) associated with Semaglutide treatment. Regarding secondary outcomes, there was an elevated risk of total adverse events and premature treatment discontinuation with Semaglutide. The risk of serious, severe, moderate, and mild adverse events did not significantly differ between the two treatments.

CONCLUSIONS

In conclusion, the administration of once-weekly Semaglutide exhibited a substantial reduction in HbA1c, average systolic blood pressure (SBP), mean diastolic blood pressure (DBP), body weight, waist circumference, body mass index (BMI), and a rise in pulse rate, as opposed to the once-daily administration of Sitagliptin.