Resistance training alone or combined with leucine supplementation improves the serum lipid profile of diabetic rats, whereas leucine alone does not

Assessment of Paraoxonase 1 and Arylesterase Activities and Lipid Profile in Bodybuilders: A Comparative Study of Physical Activity and Anthropometry on Atherosclerosis

Background and Objectives: Atherosclerosis, driven by dyslipidaemia and oxidative stress, is a leading cause of cardiovascular morbidity and mortality. This study evaluates the effects of vigorous-intensity bodybuilding exercise (VIBBE) on atherosclerosis biomarkers-including paraoxonase-1 (PON1) and arylesterase (ARE) activities-and lipid profiles in male bodybuilders who do not use anabolic-androgenic steroids. Comparisons were made with individuals engaged in moderate-intensity aerobic exercise (MIAE), as well as overweight/obese sedentary (OOS) and normal-weight sedentary (NWS) individuals. Materials and Methods: A cross-sectional study was conducted involving 122 healthy male participants aged 18-45 years, divided into four groups: VIBBE (n = 31), OOS (n = 30), MIAE (n = 32), and NWS (n = 29). Anthropometric assessments were performed, and fasting blood samples were collected for biochemical analyses, including lipid profiles and PON1 and ARE activities. Statistical analyses compared the groups and evaluated correlations between adiposity measures and atherosclerosis biomarkers. Results: The VIBBE group exhibited significantly lower levels of low-density lipoprotein cholesterol (LDL-C), triglycerides (TG), and logarithm of the TG to high-density lipoprotein cholesterol (HDL-C) ratio [log(TG/HDL-C)] compared to the OOS group (p < 0.05 for all), indicating improved lipid profiles. However, these improvements were not significant when compared to the NWS group (p > 0.05), suggesting that VIBBE may not provide additional lipid profile benefits beyond those associated with normal weight status. PON1 and ARE activities were significantly lower in the VIBBE group compared to the MIAE group (p < 0.05 for both), suggesting that VIBBE may not effectively enhance antioxidant defences. Correlation analyses revealed significant inverse relationships between PON1 and ARE activities and adiposity measures, including body mass index (BMI), waist-to-hip ratio (WHR), waist-to-height ratio (WHtR), body fat percentage (BFP), fat mass index (FMI), and obesity degree (OD) (p < 0.05 for all). Positive correlations were observed between oxLDL and log(TG/HDL-C) and adiposity measures (p < 0.05 for all). Conclusions: Vigorous-intensity bodybuilding exercise improves certain lipid parameters compared to sedentary obese individuals but does not significantly enhance antioxidant enzyme activities or further improve lipid profiles beyond those observed in normal-weight sedentary men. Conversely, moderate-intensity aerobic exercise significantly enhances PON1 and ARE activities and improves lipid profiles, offering superior cardiovascular benefits. These findings underscore the importance of incorporating moderate-intensity aerobic exercise into physical activity guidelines to optimize cardiovascular health by balancing improvements in lipid metabolism with enhanced antioxidant defences.

The Effect of Raloxifene Treatment on Lipid Profile in Elderly Individuals: A Systematic Review and Meta-analysis of Randomized Clinical Trials

PURPOSE

To perform a systematic review and meta-analysis of randomized clinical trials (RCTs) to elucidate the effects of raloxifene on the lipid profile in elderly individuals.

METHODS

A systematic review and meta-analysis of RCTs was performed following the PRISMA statement. Data on triglycerides (TGs), total cholesterol (TC), HDL-C, and LDL-C were extracted. Relevant publications up to October 2020 were detected through searches in the PubMed/MEDLINE, Web of Science, Scopus, and Embase databases. Changes were reported as weighted mean differences (WMDs) and 95% CIs using random-effects models.

FINDINGS

Nine studies were selected, with a duration of intervention ranging from 2 and 12 months and a raloxifene dose of 60 to 120 mg/d. Studies were performed in healthy individuals and in those with disorders, such as osteoporosis, type 2 diabetes, and kidney disease required long-term hemodialysis. Overall, TG (WMD, -6.50 mg/dL; 95% CI, -34.18 to 21.20 mg/eL; P = 0.646), LDL-C (WMD, -17.86 mg/dL; 95% CI, -42.44 to 6.72 mg/dL; P = 0.154), and HDL-C (WMD, 2.35 mg/dL; 95% CI, -1.14 to 5.84 mg/dL; P = 0.187) levels did not change significantly after the administration of raloxifene. In contrast, TC levels decreased after raloxifene therapy (WMD, -6.59 mg/dL; 95% CI, -13.13 to -0.05 mg/dL; P = 0.048).

IMPLICATIONS

Raloxifene therapy decreased TC levels but did not alter TG, HDL-C, and LDL-C concentrations in elderly individuals. Regarding the LDL-C levels, although the finding lacked statistical significance, we believe that there was a mean reduction that deserves further clinical attention as much as TC.

A comparative study of the antidiabetic effect of two training protocols in streptozotocin-nicotinamide diabetic rats

Background Physical inactivity is the major risk factor for type 2 diabetes (T2D). The present study was conducted to investigate the effects of resistance training and endurance training on diabetic-related metabolic parameters in diabetic rats. Materials and methods Twenty-four male Wistar rats were randomly assigned to four groups of six rats each: control group (C), diabetic group (D), resistance training group (RES) and endurance training group (END). T2D was induced intraperitoneally using nicotinamide (120 mg/kg) and streptozotocin (STZ, 65 mg/kg). The training period was 70 days. The irisin, betatrophin, insulin, fasting blood glucose (FBG) and lipid profiles were measured in the serum of all rats. Results Diabetes significantly increased serum levels of FBG (p < 0.001), which were decreased significantly after the administration of training (p < 0.001). Training administration had a significant effect in normalizing serum lipid profiles (p < 0.001) and it was shown to increase the serum levels of irisin, betatrophin (p < 0.001) and insulin (END: p < 0.001 and resistance training: p < 0.05). It was also found that the endurance training was more effective in improving this parameters when compared with resistance training (p < 0.05). In addition, the irisin revealed a significant positive association with betatrophin (END: p < 0.01 and resistance training: p < 0.05) and insulin (END: p < 0.01 and RES: p < 0.05) values in diabetic groups. Conclusion This study demonstrated that endurance training was more effective in diabetic related metabolic derangement compared with resistance training. This effect is probably due to better regulation of irisin, betatrophin and insulin relative to resistance training.