Effects of epigallocatechin-3-gallate of Camellia sinensis leaves on blood pressure, lipid profile, atherogenic index of plasma and some inflammatory and antioxidant markers in type 2 diabetes mellitus patients: a clinical trial

Abstract

BackgroundIn patients with type 2 diabetes mellitus (T2DM) the inflammatory and metabolic responses to epigallocatechin-3-gallate (EGCG) are unknown.ObjectivesEvaluate the impacts of EGCG on metabolic factors and some biomarkers of stress oxidative in patients with T2DM.MethodsIn this randomized, double-blind, placebo-controlled trial, 50 patients with T2DM consumed either 2 tablets (300 mg) EGCG (n=25) or wheat flour as placebo (n=25) for 2 months. The total antioxidant capacity (TAC), interleukin-6 (IL-6), lipid profile, mean arterial pressure (MAP), atherogenic index of plasma (AIP) were evaluated before and after the intervention.ResultsThe finding of present study exhibited a significant increase in the serum levels of TAC after the EGCG supplementation (p=0.001). Also, in compare with control group, the mean changes of TAC were significantly higher in supplement group (p=0.01). In intervention group, a significant decrease was observed in the mean levels of triglyceride, total cholesterol, diastolic blood pressure (DBP), AIP, and MAP (p<0.05). Taking EGCG resulted in the mean changes of total cholesterol, MAP and DBP were significantly lower in compare with control group (p<0.05).ConclusionsThis study recommended that EGCG supplementation may be improved blood pressure, lipid profile, AIP, and oxidative status in patients with T2DM.

Effect of Green Tea Supplementation on Antioxidant Status in Adults: A Systematic Review and Meta-Analysis of Randomized Clinical Trials

“…Consequently, 42 studies were retrieved for full-text review, 26 of which were excluded due to: lack of sufficient data and the use of two or more interventions at the same time [ 2 , 21 , 22 , 24 , 30 , 34 , 40 , 41 , 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49 , 50 , 51 , 52 , 53 , 54 , 55 , 56 , 57 , 58 , 59 , 60 , 61 ]. Finally, sixteen RCTs with one double-arm study [ 4 , 5 , 9 , 10 , 13 , 22 , 24 , 29 , 37 ] were eligible for this systematic review and meta-analysis. The flow chart of the literature search is shown in Figure 1 .…”

“…Sixteen RCTs with one double-arm study assessing the effects of green tea supplementation on oxidative stress were identified. Included studies carried out in various countries such as Iran [ 5 , 9 , 22 , 24 , 33 , 36 , 37 ], Poland [ 4 , 29 , 31 , 32 ], Lithuania [ 13 , 31 ], Taiwan [ 34 , 35 ] and Brazil [ 10 ]. Publication dates ranged from 2009 and 2020.…”

“…The sample size of the included studies ranged from eight to forty-eight participants. Some studies enrolled only females [ 35 ] or males [ 4 , 5 , 9 , 31 , 34 , 36 ], and the rest of included studies involved both genders [ 10 , 13 , 22 , 24 , 29 , 32 , 33 , 37 ], and one of them was unclear [ 31 ]. Type of intervention administration were green tea [ 9 , 22 , 24 , 34 , 35 ] and green tea extract [ 4 , 5 , 9 , 10 , 13 , 29 , 32 , 34 , 36 , 37 ].…”

“…Two studies had low random sequence generation [ 29 , 30 ]. Allocation concealment reported in 15 studies [ 4 , 5 , 10 , 13 , 23 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 ]. Moreover, 3 trials had a high risk of bias regarding blinding of participants, personnel [ 9 , 24 , 31 ], and 3 trials had low-risk outcome assessors [ 22 , 29 , 34 ].…”

“…All of the studies showed a low risk of bias based on incomplete outcome data. Other sources of bias were low in 10 trials [ 5 , 10 , 13 , 22 , 29 , 30 , 32 , 34 , 35 , 37 ].…”