Sarcopenic Obesity with Normal Body Size May Have Higher Insulin Resistance in Elderly Patients with Type 2 Diabetes Mellitus

Prevalence of sarcopenic obesity in patients with diabetes and adverse outcomes: A systematic review and meta-analysis

BACKGROUND & AIMS

Sarcopenic obesity (SO), which refers to the coexistence of sarcopenia and obesity. The aim of this systematic review and meta-analysis was first to assess the prevalence of SO in patients with diabetes, and second, to evaluate possible adverse outcomes.

METHODS

This study was conducted in adherence to the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) guidelines and the data were collated by means of meta-analysis and narrative synthesis. We comprehensively and systematically searched PubMed, Embase, Web of Science, CBM, CNKI, Wanfang Database from the establishment of the database to December 2022, and collected related studies on SO in patients with diabetes. Using Stata 16.0 software to pool the estimates for the prevalence of SO in patients with diabetes, and a descriptive systematic review of possible adverse outcomes was performed.

RESULTS

The prevalence of 20 included studies were pooled by a random-effects model, which showed that the prevalence of SO in patients with diabetes was 27%. Subgroup analyses showed that the prevalence of SO was higher among studies using BIA (24%) to assess muscle mass, and those focused on literature of moderate-quality (29%), being published from 2013 to 2016 (29%), female patients with diabetes (17%), North Americans (30%). SO in patients with diabetes can lead to adverse outcomes including decreased glomerular filtration rate, massive proteinuria, cognitive decline, and insulin resistance.

CONCLUSION

The systematic review and meta-analysis revealed a prevalence of 27% for SO in patients with diabetes, and it is associated with potential serious adverse outcomes. Therefore, we should attach importance to the screening of SO in patients with diabetes and early detection of susceptible groups, then selecting appropriate interventions to reduce the occurrence of it and various adverse outcomes in this demographic.

Can Antidiabetic Medications Affect Telomere Length in Patients with Type 2 Diabetes? A Mini-Review

The fight against aging is an eternal pursuit of humankind. The aging rate of patients with type 2 diabetes mellitus (T2DM) is higher than that of healthy individuals. Reducing the aging rate of patients with T2DM and extending their life expectancy are challenges that endocrinologists are eager to overcome. Many studies have shown that antidiabetic medications have potent anti-aging potential. Telomeres are repetitive DNA sequences located at the ends of chromosomes, and telomere shortening is a hallmark of aging. This review summarizes clinical trials that have explored the association between antidiabetic medications and telomere length (TL) in patients with T2DM and explore the mystery of delaying aging in patients with T2DM from the perspective of telomeres. Various antidiabetic medications may have different effects on TL in patients with T2DM. Metformin and sitagliptin may protect telomeres in patients with T2DM, while exogenous insulin may promote telomere shortening in patients with T2DM. The effect of acarbose and glyburide on TL in patients with T2DM is still uncertain due to the absence of evidence from longitudinal studies.

Azilsartan Ameliorates Skeletal Muscle Wasting in High Fat Diet (HFD)-induced Sarcopenic Obesity in Rats via Activating Akt Signalling Pathway

An association between the loss of skeletal muscle mass and obesity in the geriatric population has been identified as a disease known as sarcopenic obesity. Therefore, therapeutic/preventive interventions are needed to ameliorate sarcopenia. The present study investigates the effect of azilsartan (AZL) on skeletal muscle loss in High-Fat Diet (HFD)-induced sarcopenic obese (SO) rats. Four- and fourteen-months male Sprague Dawley rats were used and randomized in control and azilsartan treatment. 14 months animals were fed with HFD for four months and labeled as HFD-fed SO rats. Young & old rats received 0.5% carboxymethyl cellulose as a vehicle/AZL (8 mg/kg, per oral) treatment for six weeks. Grip strength and body composition analysis were performed after the last dose of AZL. Serum and gastrocnemius (GN)muscles were collected after animal sacrifice. AZL treatment significantly increased lean muscle mass, grip strength, myofibrillar protein, and antioxidant (superoxide dismutase & nitric oxide) levels in SO rats. AZL also restored the muscle biomarkers (creatine kinase, myostatin & testosterone), and insulin levels. AZL improves cellular, and ultracellular muscle structure and prevents type I to type II myofiber transitions in SO rats. Further, immunohistochemistry results showed increased expressions of pAkt and reduced expression of MuRF-1 and TNF-α exhibiting that AZL intervention could decrease protein degradation in SO rats. In conclusion, present results showed that AZL significantly increased lean mass, and restored muscle biomarkers, and muscle architecture. Taken together, the aforementioned findings suggest that azilsartan could be a possible therapeutic approach to reduce muscle wasting in sarcopenic obesity.

Identification and Characterization of Genomic Predictors of Sarcopenia and Sarcopenic Obesity Using UK Biobank Data

The substantial decline in skeletal muscle mass, strength, and gait speed is a sign of severe sarcopenia, which may partly depend on genetic risk factors. So far, hundreds of genome-wide significant single nucleotide polymorphisms (SNPs) associated with handgrip strength, lean mass and walking pace have been identified in the UK Biobank cohort; however, their pleiotropic effects on all three phenotypes have not been investigated. By combining summary statistics of genome-wide association studies (GWAS) of handgrip strength, lean mass and walking pace, we have identified 78 independent SNPs (from 73 loci) associated with all three traits with consistent effect directions. Of the 78 SNPs, 55 polymorphisms were also associated with body fat percentage and 25 polymorphisms with type 2 diabetes (T2D), indicating that sarcopenia, obesity and T2D share many common risk alleles. Follow-up bioinformatic analysis revealed that sarcopenia risk alleles were associated with tiredness, falls in the last year, neuroticism, alcohol intake frequency, smoking, time spent watching television, higher salt, white bread, and processed meat intake; whereas protective alleles were positively associated with bone mineral density, serum testosterone, IGF1, and 25-hydroxyvitamin D levels, height, intelligence, cognitive performance, educational attainment, income, physical activity, ground coffee drinking and healthier diet (muesli, cereal, wholemeal or wholegrain bread, potassium, magnesium, cheese, oily fish, protein, water, fruit, and vegetable intake). Furthermore, the literature data suggest that single-bout resistance exercise may induce significant changes in the expression of 26 of the 73 implicated genes in m. vastus lateralis, which may partly explain beneficial effects of strength training in the prevention and treatment of sarcopenia. In conclusion, we have identified and characterized 78 SNPs associated with sarcopenia and 55 SNPs with sarcopenic obesity in European-ancestry individuals from the UK Biobank.

Predictive Roles of Basal Metabolic Rate and Body Water Distribution in Sarcopenia and Sarcopenic Obesity: The link to Carbohydrates

Sarcopenic obesity is a new category of obesity and is a specific condition of sarcopenia. This study aimed to find the relationship of the basal metabolic rate (BMR) and body water distribution with muscle health and their prospective roles in screening for sarcopenic obesity and sarcopenia. The role of nutrients such as carbohydrates in the relationship was further detected. A total of 402 elderly subjects were recruited. Body composition was estimated by bioelectrical impedance analysis. Sarcopenia was defined by the Asian Working Group for Sarcopenia 2019. The cutoff values were determined by the receiver operating characteristic curve. Mediation analyses were performed using SPSS PROCESS. Higher BMR and BMR/body surface area (BSA) were protective factors against sarcopenic obesity (OR = 0.047, p = 0.004; OR = 0.035, p = 0.002) and sarcopenia (OR = 0.085, p = 0.001; OR = 0.100, p = 0.003) in elderly people. Low extracellular water (ECW)/intracellular water (ICW) and ECW/total body water (TBW) were negatively correlated with the skeletal muscle index (SMI). The intake of dietary carbohydrates in people with sarcopenic obesity was the lowest, but in subjects with obesity, it was the highest (p = 0.023). The results of the moderated mediation model showed that BMR fully mediated the positive relationship between carbohydrates and SMI, which was more obvious in the population with an abnormal body water distribution. BMR or BMR/BSA had the potential role of predicting a higher risk of sarcopenic obesity and sarcopenia. Higher BMR and lower ECW/ICW and ECW/TBW may benefit muscle health. The overconsumption of carbohydrates (especially > AMDR) might be a risk factor for obesity. Moderate dietary carbohydrate intake might promote SMI by regulating BMR and body water distribution in the elderly.