How Does Testosterone Augment the Anabolic Response to Exercise in Frail Older Adults?

Testosterone treatment increases muscle mass, strength, and leg power in menopausal women, hypogonadal men, older men with mobility limitation, COPD and ESRD. Testosterone's effects on muscle mass and strength are augmented by exercise training and growth hormone. Testosterone treatment improves some measures of physical performance, such as stair climbing power and aerobic capacity; the improvements in gait speed have been modest. Testosterone increases muscle mass by inducing the hypertrophy of type 1 and 2 muscle fibers, and by increasing satellite cell number. Testosterone promotes the differentiation of mesenchymal progenitor cells into myogenic lineage and inhibits their differentiation into adipogenic lineage by activating Wnt-target genes, including follistatin that plays an important role in mediating testosterone's effects on the muscle. Testosterone also increases polyamine synthesis in the muscle. Combined administration of testosterone plus multi-component exercise intervention that includes functional training may be needed to improve function and mobility in older adults.

Testosterone Protects Mice Against Zika Virus Infection And Suppresses The Inflammatory Response In Brain

Background: Testosterone is an important hormone affecting human growth and development. Recent studies have shown that testosterone is related to immune regulation. Infection with Zika virus (ZIKV) can cause testicular damage and decrease testosterone secretion. However, whether testosterone plays a function in the pathogenesis of ZIKV is still unclear. The main objective of this study was to understand the role of testosterone in central nervous system injury and inflammation induced by ZIKV. Methods: In this work, a mouse model was used to evaluate the role of testosterone in ZIKV infection. Histopathological analysis, flow cytometry, and real-time PCR were performed to investigate the mechanism by which testosterone improved survival in mice after ZIKV infection.Results: ZIKV infection caused testicular damage and decreased testosterone secretion in mice, and testosterone supplementation after ZIKV infection reduced mortality and pathological symptoms in mice. Histopathological analysis showed that testosterone treatment after ZIKV infection could reduce inflammatory cell infiltration in the brain and alleviate brain injury. Flow cytometry and quantitative real-time PCR results confirmed that testosterone treatment could reduce the CD8+ T cell infiltration and the expression of interferon gamma and inflammatory cytokines induced by ZIKV. Conclusion: Testosterone plays an important protective role in mice during ZIKV infection and can be used as a potential therapeutic treatment for ZIKV infection.

Efficacy of preoperative testosterone therapy in hypospadias: a systematic review and meta-analysis

Background Bleeding, hematoma, edema, wound infection, and scar formation are the common problems linked with hypospadias reconstruction. Hormone treatment is recommended before surgical treatment to improve intraoperative circumstances. However, no meta-analysis has explored the effectiveness and side effects of testosterone treatment before surgery in hypospadias. Main body of the abstract The purpose of this paperwork is to evaluate the impact of preoperative testosterone treatment in hypospadias based on clinical data from published trials. This study searched MEDLINE, Science Direct, and the Cochrane Library without regard to year. However, only English journals were included, with a manual search using the Preferred Reporting Items for Systematic Reviews and Meta-analysis of Observational Studies in Epidemiology Guidelines supplementing the search. In this meta-analysis, five papers were considered. Two of these investigations were multicenter randomized clinical trials. Two of the studies were prospective, with a median follow-up of varying lengths. A retrospective investigation was conducted. There were 585 patients in all that took part in this trial. After surgery, the complication rate was measured in both the intervention and control groups, including meatal stenosis, fistula, glans dehiscence, scarring, reoperation rate, urethral diverticulum, fine pubic hair, and sexual precocity. The only significant difference between the intervention and control groups was that the intervention group had a decreased frequency of glans dehiscence following surgery (OR 0.40 with the 95% CI of 0.17 until 0.97). Conclusions This study discovered that a patient who got testosterone before surgery had a considerably decreased complication risk for glandular dehiscence. Reoperation rate, urethral-cutaneous fistula, meatal stenosis, and penile scarring in children with hypospadias, on the other hand, revealed no significant difference in the testosterone-treated group against the control group.

In-vivo skeletal muscle mitochondrial function in Klinefelter syndrome

Klinefelter syndrome (XXY) occurs in 1 in 600 males, resulting in testosterone deficiency and a high prevalence of insulin resistance. Testosterone deficiency in men is a known cause of insulin resistance, and mitochondrial dysfunction is hypothesized to mediate this relationship. The aim of this cross-sectional study was to evaluate muscle mitochondrial function in XXY compared with male controls. Twenty-seven boys with XXY (age 14.7±1.8 years) were compared with 87 controls (age 16.9±0.9). In-vivo calf muscle mitochondrial function was assessed via phosphorus magnetic resonance spectroscopy (31P-MRS) following 90 s of isometric 70% maximal exercise. Multiple linear regression was used to compare 31P-MRS outcomes (ADP and phosphocreatine (PCr) time constants, rate of oxidative phosphorylation (Oxphos), and Qmax or the maximal mitochondrial function relative to mitochondrial density) between groups after adjusting for age differences. There were no statistically significant differences in the mitochondrial outcomes of ADP, Oxphos, PCr, and Qmax between the groups. There were also no differences in a sensitivity analysis within the XXY group by testosterone treatment status. In this study, in-vivo postexercise skeletal muscle mitochondrial function does not appear to be impaired in adolescents with XXY compared with controls and is not significantly different by testosterone treatment status in XXY.