The Effects of Green Tea Consumption on Cardiometabolic Alterations Induced by Experimental Diabetes

Abstract

We evaluated cardiac autonomic modulation by heart rate (HRV), and arterial pressure variability (APV), and metabolic response in streptozotocin diabetic rats treated with green tea. Male Wistar rats were separated in groups: control, drinking tap water (C), green tea-treated (GT) group, diabetic, drinking tap water (D), and diabetic, treated with green tea (DGT). Kidney mass was greater in D and DGT than in C and GT, but reduced in DGT compared to D. Green tea prevented the increase in creatinine clearance and reduced hyperglycemia in DGT compared to D. Arterial pressure was increased in GT and decreased in D compared to C. HRV was reduced in D compared with all groups. APV was decreased in D compared to C and recovery in DGT. Sympathetic modulation of APV was decreased in D compared with all groups. Green tea reduced hyperglycemia, prevented renal injury and autonomic dysfunction, suggesting reduced cardiovascular risk and target organ damage in diabetes.

White tea consumption improves cardiac glycolytic and oxidative profile of prediabetic rats

“…In our work, although WTEA consumption by prediabetic rats did not restore blood glycaemia to control values, it improved glucose tolerance and insulin resistance. It has been reported that GT consumption and/or administration ameliorates glucose metabolism in diabetic individuals (Babu, Sabitha, Srinivasan, & Shyamaladevi, 2007;Fiorino et al, 2012;Tang et al, 2013). The normoinsulinaemia effect and glucose metabolism improvement caused by tea consumption has been attributed to the antioxidant properties of tea.…”

Effects and Mechanisms of Tea for the Prevention and Management of Diabetes Mellitus and Diabetic Complications: An Updated Review

“…Furthermore, green tea catechins could protect kidney function by reducing the permeability of glomerular filtration membrane through inhibiting thrombosis with lowered microsomal phospholipase A2 and regulating arachidonic acid cascade system [42]. An in vivo study also found that green tea could improve glomerular filtration and reduce the rate of creatinine increase and renal hypertrophy [77]. Further, in diabetic spontaneously hypertensive rats (SHRs), green tea prevented podocyte apoptosis and albuminuria by rising p-low-density lipoprotein receptor-related protein 6 (p-LRP6) expression and blocking glycogen synthase kinase 3 interaction with p53 (GSK3-p53) [78].…”

“…Cardiovascular complications, containing cardiomyopathy, atherosclerosis, coronary ischemia, and vascular disease, are associated with the high morbidity and mortality of diabetes mellitus [77,88], among which cardiomyopathy is responsible for 80% [17]. It was reported that tea could improve cardiovascular complications by decreasing hyperglycemia, adjusting lipid metabolism, activating signaling pathways, down-regulating the inflammatory factors, and so on.…”

“…Also, MMP-9 played an important role in atherosclerosis, and green tea catechins could inhibit the mRNA expression and the activity of MMPs [83,99]. Further, green tea catechins increased plasma total antioxidant activity and prevented diabetic cardiovascular autonomic dysfunction by blocking changes in arterial pressure variability [77]. Moreover, the green tea extract inhibited the accumulation of aortic collagen, reduced the solubility of collagen, and decreased AGEs and collagen cross-linking, finally preventing diabetic cardiomyopathy in streptozotocin diabetic rats [98,100].…”

Hypoglycemic Property of Ginger and Green Tea and their Possible Mechanisms in Diabetes Mellitus

“…Several studies suggested that administration of green tea or its main constituents by different routes, in various doses, and in different length of time lowered the blood glucose level in type 1 induced diabetic animals [41,56,[66][67][68][69].…”