Move Your Body toward Healthy Aging: Potential Neuroprotective Mechanisms of Irisin in Alzheimer's Disease.

Alzheimer's disease (AD) is the leading cause of dementia in older adults, having a significant global burden and increasing prevalence. Current treatments for AD only provide symptomatic relief and do not cure the disease. Physical activity has been extensively studied as a potential preventive measure against cognitive decline and AD. Recent research has identified a hormone called irisin, which is produced during exercise, that has shown promising effects on cognitive function. Irisin acts on the brain by promoting neuroprotection by enhancing the growth and survival of neurons. It also plays a role in metabolism, energy regulation, and glucose homeostasis. Furthermore, irisin has been found to modulate autophagy, which is a cellular process involved in the clearance of protein aggregates, which are a hallmark of AD. Additionally, irisin has been shown to protect against cell death, apoptosis, oxidative stress, and neuroinflammation, all of which are implicated in AD pathogenesis. However, further research is needed to fully understand the mechanisms and therapeutic potential of irisin in AD. Despite the current gaps in knowledge, irisin holds promise as a potential therapeutic target for slowing cognitive decline and improving quality of life in AD patients.

Lipid profile and risk of cardiovascular disease in adult transgender men receiving cross-sex hormone therapy: a systematic review.

CONTEXT: A recent US national survey of the health status of the male transgender population has raised awareness about the little-studied relationship between testosterone hormone therapy in transgender men and cardiovascular outcomes. OBJECTIVE: The aim of this systematic review was to assess the relationship between cross-sex hormone therapy in transgender men and lipid profiles and cardiovascular risk. DATA SOURCES: The PubMed, SciELO, SpringerLink, and EBSCOhost databases were searched up to March 2021 for studies assessing the association between cross-sex hormone therapy and the incidence of outcomes related to cardiovascular disease in transgender men over 18 years of age . DATA EXTRACTION: Data extracted were sorted into clinical data (systolic, diastolic, and mean blood pressure), anthropometric data (body mass index, weight, waist circumference, fat mass, and lean mass), and biochemical data (triglycerides, total cholesterol, low-density lipoprotein cholesterol [LDL-C], high-density lipoprotein cholesterol [HDL-C], very low-density lipoprotein cholesterol [VLDL-C], and the HDL-C to LDL-C ratio). DATA ANALYSIS: Study quality was appraised independently by two reviewers using the Cochrane tools for assessment of methodological quality or risk of bias in nonrandomized studies, and the Newcastle-Ottawa Scale was applied. Of 735 studies identified, 11 were included in the review. Most studies reported no change in cholesterol or triglyceride levels after hormone treatment. A reduction in HDL-C levels was observed in 7 of 11 studies, although this alone cannot be considered a cardiovascular risk factor. Likewise, clinical and anthropometric findings showed no changes predictive of cardiovascular risk. CONCLUSIONS: Although these findings suggest that hormone therapy may lead to a decrease in HDL-C levels and an increase in LDL-C levels, they are insufficient to establish a relationship with cardiovascular disease. Furthermore, no significant effects on metabolic and anthropometric values were found. Further studies with higher quality and longer follow-up periods are needed to establish cardiovascular risk. SYSTEMATIC REVIEW REGISTRATION: PROSPERO registration number CRD 42020212560.