1. Introduction

iabetes mellitus is the most common metabolic disease [2]. In diabetic patients, metabolic flexibility is impaired. Today, in addition to various sports exercises, other non-pharmacological solutions of plant origin have been considered for the management of diabetes [13, 14]. Wang et al. [12] found that those who did not exercise had a 2.2-fold increase in the expression of Pyruvate Dehydrogenase Kinase (PDK4) following resistance exercise and symmetric endurance exercise compared to single-mode endurance exercise. Sin et al. [19], by reviewing the anti-glycemic mechanism of Resveratrol in skeletal muscle of aged and diabetic patients, confirmed the changes in the expression of PDK4 through the Pparg Coactivator-1 Alpha (PGC-1α) pathway following Resveratrol consumption. The aim of present study was to examine the effect of periodic exercise and resveratrol supplementation on the expression of PDK4 and PGC-1α genes in gastrocnemius muscle of old rats with type 2 diabetes.

2. Methods and Materials

This is an experimental study conducted in 2018 in the research center of Islamic Azad University of Sari branch. 42 male rats (mean age=40-50 weeks; mean body weight=250-300 g) were randomly divided into 6 groups: healthy-control, diabetic-control, Diabetic+Periodic Exercise, Diabetic+Supplement, Diabetic+Periodic Exercise+Supplement, and Saline. The type 2 diabetes was induced by intraperitoneal injection of Streptozotocin (50 mg/kg body weight).

The exercise protocol consisted of 10 sets of 1-min activities at 50% intensity and a 2-min rest period between sets, and each week the speed was increased by 2 meters per minute. The exercises were performed for eight weeks. Resveratrol supplement was injected intraperitoneally daily at a dose of 20 mg/kg body weight. The expressions of PDK4 and PGC-1α in the gastrocnemius muscle were measured by real time Polymerase Chain Reaction (PCR) method. After quantification, gene expression values were analyzed using 2-∆∆Ct formula.

3. Results

According to the results shown in Figure 1, the highest expression level of PDK4 gene in gastrocnemius muscle was observed in the diabetic group received both periodic exercise and Resveratrol supplement and the lowest level was reported in the diabetic-control and saline groups.

The increase in PDK4 level in the rats treated with a combination of resveratrol and periodic exercise was significantly higher than that of those received resveratrol and periodic exercise alone (P<0.001). The results also show that the highest expression of PGC-1α gene was in the diabetic group received both periodic exercise and Resveratrol supplement and its lowest levels in the diabetic-control group (Figure 2). The increase in PGC-1α level in the rats treated with a combination of resveratrol and periodic exercise was significantly higher than that of those received resveratrol and periodic exercise alone (P <0.001).

4. Discussion

A number of previous studies have shown that diabetes is associated with an increase in the concentration of PDK4, a decrease in its gene expression, and its poor function [9, 11, 24]. In the present study, we found that the expression of the PDK4 gene in diabetic rats increased after administration of resveratrol to the gastrocnemius muscle tissue. Similarly, previous studies have shown that resveratrol supplementation can improve the complications of muscle aging and insulin resistance [13, 19].

Resveratrol supplementation can also increase the transactivation of PDK4 in response to decreased protein content of PDK4 [19]. In the present study, it was also observed that mRNA expression of PDK4 was higher in the resveratrol supplementation+periodic exercise group than in diabetic and saline groups. Wang et al. showed that after exercise, mRNAs associated with PGC-1α and PDK4 increased 5-8 times in both types of muscle fibers [12].

In the present study, changes in PGC-1α gene expression were consistent with the results of PDK4 gene. We suggest that a combination of resveratrol and periodic exercise be further studied as an effective way to improve glucose uptake in gastrocnemius muscles of older rats with type 2 diabetes.

5. Conclusion

The combination of resveratrol supplementation and periodic exercise can have beneficial effects on PDK4 and PGC-1α expression levels in the gastrocnemius muscle of old rats with type 2 diabetes and reduce the risks of diabetes-related complications.

Ethical Considerations

Compliance with ethical guidelines

This study was approved by the Animal Care and Use Committee of Islamic Azad University of Sari branch (Ethical Code: IR.IAU.SARI.REC.1397.011). All ethical principles governing animal experiments were fully met.

Funding

The present paper was extracted from the PhD dissertation of the first author, Department of Exercise Physiology, Sari Branch, Islamic Azad University, Sari.

Authors' contributions

Conceptualization, investigation, writing – review & editing, supervision: All Authors; Methodology, writing – original draft, resources: Ali Salehi, Hajar Abbaszadeh; Funding acquisition: Ali Salehi.

Conflicts of interest

The authors declared no conflict of interest.

Acknowledgements

The authors would like to thank the animal laboratory staff of Islamic Azad University of Sari branch for their valuable cooperation.


 

References

1. Gray DWR, Titus N, Badet L. Islet cell transplantation for insulin-dependent diabetes mellitus: Perspectives from the present and prospects for the future. Expert Reviews in Molecular Medicine. 2000; 2(6):1-28. [DOI:10.1017/S1462399400001861] [PMID]
2. Biensø RS, Olesen J, Gliemann L, Schmidt JF, Matzen MS, Wojtaszewski JF, et al. Effects of exercise training on regulation of skeletal muscle glucose metabolism in elderly men. Journals of Gerontology Series A: Biomedical Sciences and Medical Sciences. 2015; 70(7):866-72. [DOI:10.1093/gerona/glv012] [PMID]
3. Traub O, Van Bibber R. Role of nitric oxide in insulin-dependent diabetes mellitus-related vascular complications. Western Journal of Medicine. 1995; 162(5):439-45. [PMID] [PMCID]
4. Jeoung NH. Pyruvate dehydrogenase kinases: Therapeutic targets for diabetes and cancers. Diabetes & Metabolism Journal. 2015; 39(3):188-97. [DOI:10.4093/dmj.2015.39.3.188] [PMID] [PMCID]
5. Wang L, Sahlin K. The effect of continuous and interval exercise on PGC‐1α and PDK4 mRNA in type I and type II fibres of human skeletal muscle. Acta Physiologica. 2012; 204(4):525-32. [DOI:10.1111/j.1748-1716.2011.02354.x] [PMID]
6. Bowker-Kinley MM, Davis WI, Wu P, Harris RA, Popov KM. Evidence for existence of tissue-specific regulation of the mammalian pyruvate dehydrogenase complex. Biochemical Journal. 1998; 329(Pt 1):191-6. [DOI:10.1042/bj3290191] [PMID] [PMCID]
7. Zhang Sh, Hulver MW, McMillan RP, Cline MA, Gilbert ER. The pivotal role of pyruvate dehydrogenase kinases in metabolic flexibility. Nutrition & Metabolism. 2014; 11:10. [DOI:10.1186/1743-7075-11-10] [PMID] [PMCID]
8. Puigserver P, Spiegelman BM. Peroxisome proliferator-activated receptor-γ coactivator 1α (PGC-1α): Transcriptional coactivator and metabolic regulator. Endocrine Reviews. 2003; 24(1):78-90. [DOI:10.1210/er.2002-0012] [PMID]
9. Wende AR, Huss JM, Schaeffer PJ, Giguere V, Kelly DP. PGC-1α coactivates PDK4 gene expression via the orphan nuclear receptor ERRα: A mechanism for transcriptional control of muscle glucose metabolism. Molecular and Cellular Biology. 2005; 25(24):10684-94. [DOI:10.1128/MCB.25.24.10684-10694.2005] [PMID] [PMCID]
10. Niklas P, Li W, Jens W, Michail T, Kent S. Mitochondrial gene expression in elite cyclists: Effects of high-intensity interval exercise. European Journal of Applied Physiology. 2010; 110(3):597-606. [DOI:10.1007/s00421-010-1544-1] [PMID]
11. Lee IK. The role of pyruvate dehydrogenase kinase in diabetes and obesity. Diabetes & Metabolism Journal. 2014; 38(3):181-6. [DOI:10.4093/dmj.2014.38.3.181] [PMID] [PMCID]
12. Wang L, Mascher H, Psilander N, Blomstrand E, Sahlin K. Resistance exercise enhances the molecular signaling of mitochondrial biogenesis induced by endurance exercise in human skeletal muscle. Journal of Applied Physiology. 2011; 111(5):1335-44. [DOI:10.1152/japplphysiol.00086.2011] [PMID]
13. Movahed A. [Beneficial effects of resveratrol on reducing blood glucose and insulin resistance in T2DM (Persian)]. Iranian South Medical Journal. 2016; 19(1):155-66. [DOI:10.7508/ismj.1395.01.013]
14. Nasri S. [The effect of Resveratrol flavonoid on learning and memory in passive avoidance and Y maze in diabetic rat (Persian)]. Iranian South Medical Journal. 2014; 17(1):11-20. http://ismj.bpums.ac.ir/article-1-500-en.html
15. Brown VA, Patel KR, Viskaduraki M, Crowell JA, Perloff M, Booth TD, et al. Repeat dose study of the cancer chemopreventive agent resveratrol in healthy volunteers: Safety, pharmacokinetics, and effect on the insulin-like growth factor axis. Cancer Research. 2010; 70(22):9003-11. [DOI:10.1158/0008-5472.CAN-10-2364] [PMID] [PMCID]
16. Shang J, Chen LL, Xiao FX, Sun H, Ding HC, Xiao H. Resveratrol improves non-alcoholic fatty liver disease by activating AMP-activated protein kinase. Acta Pharmacologica Sinica. 2008; 29(6):698-706. [DOI:10.1111/j.1745-7254.2008.00807.x] [PMID]
17. Rubiolo JA, Mithieux G, Vega FV. Resveratrol protects primary rat hepatocytes against oxidative stress damage: Activation of the Nrf2 transcription factor and augmented activities of antioxidant enzymes. European Journal of Pharmacology. 2008; 591(1-3):66-72. [DOI:10.1016/j.ejphar.2008.06.067] [PMID]
18. Mohajeri D, Monadi AR, Mousavi Gh, Rezaei Saber AP. [Cardioprotective effect of resveratrol on isoproterenol-induced experimental myocardial infarction in rat (Persian)]. Veterinary Clinical Pathology. 2014; 8(3):537-48. https://www.sid.ir/fa/journal/ViewPaper.aspx?ID=253770
19. Sin TK, Yung BY, Siu PM. Modulation of SIRT1-Foxo1 signaling axis by resveratrol: Implications in skeletal muscle aging and insulin resistance. Cellular Physiology and Biochemistry. 2015; 35(2):541-52. [DOI:10.1159/000369718] [PMID]
20. Linden MA, Fletcher JA, Matthew Morris E, Meers GM, Harold Laughlin M, Booth FW, et al. Treating NAFLD in OLETF rats with vigorous-intensity interval exercise training. Medicine and Science in Sports and Exercise. 2015; 47(3):556-67. [DOI:10.1249/MSS.0000000000000430] [PMID] [PMCID]
21. Mozafari M, Nekooeian AA, Panjeshahin MR, Zare HR. The effects of resveratrol in rats with simultaneous type 2 diabetes and renal hypertension: A study of antihypertensive mechanisms. Iranian Journal of Medical Sciences. 2015; 40(2):152-60. [PMID] [PMCID]
22. Delaviz H, Davoudi P, Sharif Talebian Pour M, Rad P, Sadeghi H. [The effect of resveratrol on fetal heart tissue changes after preeclampsia induced by L-name in rats (Persian)]. Journal of Shahid Sadoughi University of Medical Sciences. 2015; 23(7):669-78. http://jssu.ssu.ac.ir/article-1-3222-en.html
23. Aminizadeh S, Habibi A, Marefati H, Shakerian S. [The role of Pyruvate Dehydrogenase Kinase 4 (PDK4) on the expression of citrate synthase in the skeletal muscle After 4 weeks of endurance training in male wistar rats (Persian)]. Journal of Rafsanjan University of Medical Sciences. 2017; 16(3):191-202. http://journal.rums.ac.ir/article-1-3660-en.html
24. Tao R, Xiong X, Harris RA, White MF, Dong XC. Genetic inactivation of pyruvate dehydrogenase kinases improves hepatic insulin resistance induced diabetes. PloS One. 2013; 8(8):e71997. [DOI:10.1371/journal.pone.0071997] [PMID] [PMCID]
25. Dlamini Z, Ntlabati P, Mbita Z, Shoba-Zikhali L. Pyruvate Dehydrogenase Kinase 4 (PDK4) could be involved in a regulatory role in apoptosis and a link between apoptosis and insulin resistance. Experimental and Molecular Pathology. 2015; 98(3):574-84. [DOI:10.1016/j.yexmp.2015.03.022] [PMID]
26. Liao ZY, Chen JL, Xiao MH, Sun Y, Zhao YX, Pu D, et al. The effect of exercise, resveratrol or their combination on Sarcopenia in aged rats via regulation of AMPK/Sirt1 pathway. Experimental Gerontology. 2017; 98:177-83. [DOI:10.1016/j.exger.2017.08.032] [PMID]
27. Egan B, Carson BP, Garcia-Roves PM, Chibalin AV, Sarsfield FM, Barron N, et al. Exercise intensity-dependent regulation of peroxisome proliferator-activated receptor γ coactivator-1α mRNA abundance is associated with differential activation of upstream signalling kinases in human skeletal muscle. The Journal of Physiology. 2010; 588(Pt 10):1779-90. [DOI:10.1113/jphysiol.2010.188011] [PMID] [PMCID]
28. Nordsborg NB, Lundby C, Leick L, Pilegaard H. Relative workload determines exercise-induced increases in PGC-1α mRNA. Medicine & Science in Sports & Exercise. 2010; 42(8):1477-84. [DOI:10.1249/MSS.0b013e3181d2d21c] [PMID]
29. Connaughton S, Chowdhury F, Attia RR, Song S, Zhang Y, Elam MB, et al. Regulation of Pyruvate Dehydrogenase Kinase isoform 4 (PDK4) gene expression by glucocorticoids and insulin. Molecular and Cellular Endocrinology. 2010; 315(1-2):159-67. [DOI:10.1016/j.mce.2009.08.011] [PMID] [PMCID]
30. Sugden MC, Holness MJ. Interactive regulation of the pyruvate dehydrogenase complex and the carnitine palmitoyltransferase system. The FASEB Journal. 1994; 8(1):54-61. [DOI:10.1096/fasebj.8.1.8299890] [PMID]
31. Roche TE, Baker JC, Yan X, Hiromasa Y, Gong X, Peng T, et al. Distinct regulatory properties of pyruvate dehydrogenase kinase and phosphatase isoforms. Progress in Nucleic Acid Research and Molecular Biology. 2001; 70:33-54,IN1-IN2,55-75. [DOI:10.1016/S0079-6603(01)70013-X]
32. Minakawa M, Kawano A, Miura Y, Yagasaki K. Hypoglycemic effect of resveratrol in type 2 diabetic model db/db mice and its actions in cultured L6 myotubes and RIN-5F pancreatic β-cells. Journal of Clinical Biochemistry and Nutrition. 2011; 48(3):237-44. [DOI:10.3164/jcbn.10-119] [PMID] [PMCID]
33. Goh KP, Lee HY, Lau DP, Supaat W, Chan YH, Koh AF. Effects of resveratrol in patients with type 2 diabetes mellitus on skeletal muscle SIRT1 expression and energy expenditure. International Journal of Sport Nutrition and Exercise Metabolism. 2014; 24(1):2-13. [DOI:10.1123/ijsnem.2013-0045] [PMID]
34. Barger JL, Kayo T, Vann JM, Arias EB, Wang J, Hacker TA, et al. A low dose of dietary resveratrol partially mimics caloric restriction and retards aging parameters in mice. PloS One. 2008; 3(6):e2264. [DOI:10.1371/journal.pone.0002264] [PMID] [PMCID]