The effect of aerobic training and hydroalcoholic extract of dill on skeletal muscle inflammation in a high-fat diet-induced obesity rat model

Abstract

Aerobic training (AT) and herbal medicine interventions are effective in reducing chronic inflammation and achieving weight loss. The present study aimed to investigate the effect of 10 weeks of AT and hydroalcoholic extract of dill (HED) on tumour necrosis factor-alpha (TNF-α), interleukin-4 (IL-4), and peroxisome proliferator-activated receptor gamma (PPARγ) concentrations in gastrocnemius muscle and Lee index of obese male rats. Thirty-two obese male Wistar rats were randomly divided into AT (70-80% of maximal oxygen uptake, 5 times/week), HED (300 mg/kg body weight, 3 times/week), AT+HED, and obese control (Ctr), and eight non-obese rats were included in the non-obese control group (NCtr). Lee index was measured before and after 10 weeks of interventions. Also, rats were sacrificed 48 hs after the last intervention session and gastrocnemius muscle was removed to measure protein concentrations of TNF-α, IL-4, and PPARγ. When compared with the pre-intervention period, the Lee index decreased in the AT and AT+HED groups and increased in the NCtr group at the post-intervention period. Also, there was no significant difference between non-obese and obese rats in the concentrations of TNF-α and IL-4, but the AT+HED group showed a higher concentration of TNF-α than the AT group. Furthermore, the expression of PPARγ protein in the HED group was higher than in the Ctr and AT groups. Although we observed the beneficial effects of AT and its combination with HED in reducing the Lee index, we found that the administration of HED compared with AT can provide better protection against some metabolic complications in the skeletal muscles of obese rats caused by a high-fat diet. Lastly, it seems that the AT combined with HED interferes with possible antiinflammatory effects of AT or HED intervention alone.