Effect of Silymarin Supplementation on Physical Performance, Muscle and Myocardium Histological Changes, Bodyweight, and Food Consumption in Rats Subjected to Regular Exercise Training

Abstract

(1) Background: Regular exercise induces physiological and morphological changes in the organisms, but excessive training loads may induce damage and impair recovery or muscle growth. The purpose of the study was to evaluate the impact of Silymarin (SM) consumption on endurance capacity, muscle/cardiac histological changes, bodyweight, and food intake in rats subjected to 60 min of regular exercise training (RET) five days per week. (2) Methods: Male Wistar rats were subjected to an eight-week RET treadmill program and were previously administered SM and vitamin C. Bodyweight and food consumption were measured and registered. The maximal endurance capacity (MEC) test was performed at weeks one and eight. After the last training session, the animals were sacrificed, and samples of quadriceps/gastrocnemius and cardiac tissue were obtained and process for histological analyzes. (3) Results: SM consumption improved muscle recovery, inflammation, and damaged tissue, and promoted hypertrophy, vascularization, and muscle fiber shape/appearance. MEC increased after eight weeks of RET in all trained groups; moreover, the SM-treated group was enhanced more than the group with vitamin C. There were no significant changes in bodyweight and in food and nutrient consumption along the study. (5) Conclusion: SM supplementation may enhance physical performance, recovery, and muscle hypertrophy during the eight-week RET program.

Effect of Silymarin Supplementation in Lung and Liver Histological Modifications during Exercise Training in a Rodent Model

“…The elevated demand of oxygen (O 2 ), fundamentally in endurance ET, promotes the inflammatory response along with modifications of the airways, and is accompanied by changes in other organs such as muscle and myocardium. It appears that the use of silymarin exhibits a benefit on the recovery and hypertrophy of quadriceps and gastrocnemius muscle and the myocardium, together with an increase in maximal endurance capacity and the improvement of the lean muscle mass and body weight of rats subjected to regular exercise training, as our research has previously reported [5]. During exertion, there is a multi-organ-function coupling triggered by muscle power in a demand for O 2 -rich blood; thus, pulmonary function is basically implicated in O 2 and CO 2 exchange and transport.…”

“…The administration of silymarin significantly optimized the race time and distance covered when compared with the other groups in the maximal effort test. In turn, it is suggested that silymarin helped to improve physical performance and induced myocardium and quadriceps/gastrocnemius muscle recovery and remodeling and improved body composition, by expanding lean muscle mass, after an 8-week exercise-training program [ 5 ]. To continue with this line of research, in the present work the hepatic changes included an increase in vascularization, specifically in the groups treated with antioxidants, and also the reduction of steatosis in all of the trained groups, with an even greater reduction observed in the group with silymarin, which was remarkably similar to that of the control group.…”

Silymarin and Inflammation: Food for Thoughts

“…Of note, SM (20 mg/kg/day i.p, 4 weeks) was demonstrated to enhance the expression of SIRT1 associated with decreased expression of NF-κB, providing anti-inflammatory effects in the hippocampus of old male rats [127]. In addition, SM was indicated to improve muscle recovery and to ameliorate inflammation and damaged tissue in rats subjected to regular exercise training [128]. Finally, a reduction in lung tissue inflammation was evident in rats subjected to 8-week exercise training due to the administration of SM (100 mg [129]).…”

Oxidative Stress, Mitochondrial Function and Adaptation to Exercise: New Perspectives in Nutrition

“…Our research group found that silymarin, the flavonolignan extract from Milk thistle, has been demonstrated to increase physical performance and to promote muscle hypertrophy and recovery at doses of 100 mg/kg after eight weeks of regular exercise in a rodent model [114]. Aside, the pretreatment with sulforaphane (SFN) from broccoli in 13-week-age Nrf2+/+ and Nrf2−/− male mice upregulated Nrf2 signaling and downstream genes, improved the endurance capacity associated with a lower OS marker, and provided protection against muscle fatigue during exhaustive exercise.…”