Impact of 8-week cold-and warm water swimming training combined with cinnamon consumption on serum METRNL, HDAC5, and insulin resistance levels in diabetic male rats

ObjectiveNumerous studies have reported the beneficial effects of exercise and the use of herbal supplements in improving type 2 diabetes and insulin resistance. However, there are still many unanswered questions about the effects of cold and hot water, exercise, and herbal supplements on meteorine-like protein (METRNL), which is considered one of the key factors influencing insulin resistance improvement in this condition. Hence, the current study aimed to address these knowledge gaps and investigate the effects of 8 weeks of warm and cold-water swimming exercise with cinnamon consumption on serum levels of METRNL, histone deacetylase-5 (HDAC5), and insulin resistance in diabetic male rats.MethodsFor this purpose, 70 diabetic male rats were randomly divided into seven groups (10 rats in each group) (1Saeidi A. Hackney A.C. Tayebi S.M. Ahmadian M. Zouhal H. Diabetes, Insulin Resistance, Fetuin-B and Exercise Training.Annals of Applied Sport Science. 2019; 7: 1-2Crossref Scopus (8) Google Scholar) Healthy control (HC), (2Tayebi S.M. Ghanbari-Niaki A. Saeidi A. Hackney A.C. Exercise Training, Neuregulin 4 and Obesity.Ann Appl Sport Sci. 2017; 5: 1-2Crossref Scopus (9) Google Scholar) Diabetic control, (3Saeidi A. Tayebi S.M. Khosravi A. Razi O. Sellami M. Abderrahman A.B. et al.Obesity, Fat Mass, Osteopontin and Exercise Training.International Journal of Applied Exercise Physiology. 2019; 8: 177-179Google Scholar) swimming training in cold water (temperature 5 °C), (4Rao Kondapally Seshasai S. Kaptoge S. Thompson A. Di Angelantonio E. Gao P. Sarwar N. et al.Diabetes mellitus, fasting glucose, and risk of cause-specific death.The New England journal of medicine. 2011; 364: 829-841Crossref PubMed Scopus (0) Google Scholar) swimming training at 5‌‌ °C + cinnamon consumption (200 mg/kg body weight), (5Petersmann A. Müller-Wieland D. Müller U.A. Landgraf R. Nauck M. Freckmann G. et al.Definition, classification and diagnosis of diabetes mellitus.Experimental and Clinical Endocrinology 127: S1-S7Crossref PubMed Scopus (0) Google Scholar) swimming training in warm water (temperature 36-35 °C), (6Kolahdouzi S. Baghadam M. Kani-Golzar F.A. Saeidi A. Jabbour G. Ayadi A. et al.Progressive circuit resistance training improves inflammatory biomarkers and insulin resistance in obese men.Physiology 205: 15-21Crossref Scopus (43) Google Scholar) swimming training in warm water (temperature 36-35 °C) + consumption of cinnamon, and (7Dezhkam N. Rezaeian N. Effect of Six Weeks of Aerobic Training on Meteorin Like Factor Response and Insulin Resistance Index in Overweight and Obese Young Women.Journal of Applied Health Studies in Sport Physiology. 2021; 8: 28-35Google Scholar) consumption of cinnamon only.ResultsThe present study revealed a significant increase in serum METRNL concentration in the cold-water swimming + cinnamon consumption group (p0.05). Additionally, noteworthy findings included a significant reduction in HDAC5 levels in both the cold-water swimming group and the cold-water swimming + cinnamon consumption group, as well as a significant decrease in fasting blood sugar (FBS) levels in all groups compared to the HC group (p<0.05).ConclusionsThe results of the present study demonstrate that the combination of cold-water swimming exercises and cinnamon extract consumption led to notable increases in serum METRNL concentration. Additionally, significant reductions were observed in HDAC5 and FBS levels. These findings highlight the potential effectiveness and benefits of the combination of cold-water swimming exercises and cinnamon extract consumption as an approach to improve diabetes-related indices.