Flavonoids from green tea reverse insulin resistance and inflammation: in vitro and in vivo evidence
DOI:
https://doi.org/10.60988/p.v37i2S.144Keywords:
flavonoids; molecular mechanisms; diabetes mellitus; phytochemicals; green teaAbstract
Flavonoids are a class of polyphenolic compounds that can be isolated from green tea (Camellia sinensis). This study has investigated the in vitro and in vivo effects of green tea flavonoids on insulin resistance and inflammation. Flavonoids were extracted from green tea using ethanol extraction followed by purification through the employment of HPLC. In vitro experiments were conducted on two cell lines in order to assess glucose uptake and inflammatory marker expression, while in vivo studies involved streptozotocin-induced diabetic mice treated with green tea-derived flavonoids (240 mg/kg) for 30 days, and with their blood glucose and glycated haemoglobin (HbA1c) levels being analysed. Our results revealed that the flavonoid treatment could significantly increase glucose uptake in vitro (p<0.05), while diabetic mice exhibited lower fasting blood glucose (p<0.001) and HbA1c (p<0.01) levels compared to untreated controls. In conclusion, these findings suggest that flavonoids may serve as effective adjunct therapies for diabetes and inflammation.
References
Al-Ishaq R.K., Abotaleb M., Kubatka P., Kajo K., Büsselberg D. Flavonoids and their anti-diabetic effects: cellular mechanisms and effects to improve blood sugar levels. Biomolecules 9(9), 430, 2019. DOI: 10.3390/biom9090430
Zhang Y., Hu T., Zhou H., Zhang Y., Jin G., Yang Y. Antidiabetic effect of polysaccharides from Pleurotus ostreatus in streptozotocin-induced diabetic rats. Int. J. Biol. Macromol. 83, 126–132, 2016. DOI: 10.1016/j.ijbiomac.2015.11.045
Zhang B., Li Y., Zhang F., Linhardt R.J., Zeng G., Zhang A. Extraction, structure and bioactivities of the polysaccharides from Pleurotus eryngii: a review. Int. J. Biol. Macromol. 150, 1342–1347, 2020. DOI: 10.1016/j.ijbiomac.2019.10.144
Scalbert A., Johnson I.T., Saltmarsh M. Polyphenols: antioxidants and beyond. Am. J. Clin. Nutr. 81(1s), 215s–217s, 2005. DOI: 10.1093/ajcn/81.1.215s
Spencer J.P., Abd El Mohsen M.M., Minihane A.M., Mathers J.C. Biomarkers of the intake of dietary polyphenols: strengths, limitations and application in nutrition research. Br. J. Nutr. 99(1), 12–22, 2008. DOI: 10.1017/S0007114507798938
Fraga C.G., Croft K.D., Kennedy D.O., Tomás-Barberán F.A. The effects of polyphenols and other bioactives on human health. Food Funct. 10(2), 514–528, 2019. DOI: 10.1039/c8fo01997e
Miyake Y., Yamamoto K., Tsujihara N., Osawa T. Protective effects of lemon flavonoids on oxidative stress in diabetic rats. Lipids 33(7), 689–695, 1998. DOI: 10.1007/s11745-998-0258-y
Ren N., Kim E., Li B., Pan H., Tong T., Yang C.S., et al. Flavonoids alleviating insulin resistance through inhibition of inflammatory signaling. J. Agric. Food Chem. 67(19), 5361–5373, 2019. DOI: 10.1021/acs.jafc.8b05348
Gasmi A., Mujawdiya P.K., Noor S., Lysiuk R., Darmohray R., Piscopo S., et al. Polyphenols in metabolic diseases. Molecules 27(19), 6280, 2022. DOI: 10.3390/molecules27196280
Middleton E.Jr, Kandaswami C., Theoharides T.C. The effects of plant flavonoids on mammalian cells: implications for inflammation, heart disease, and cancer. Pharmacol. Rev. 52(4), 673–751, 2000.
