Diabetes and Metabolism Journal

Korean Diabetes Association (대한당뇨병학회)
권호 표지

The Effect of Green Tea Polyphenol on Plasma Glucose, Lipid Levels and Antioxidant Systems in Type 2 Diabetic Patients

녹차 폴리페놀이 제2형 당뇨병환자의 혈당, 지질 및 항산화 체계에 미치는 영향

Suk, Ji-Hye;Kim, Mi-Kyung;Ju, Jae-Won;Han, Ji-Sook;Park, Jeong-Hyun
석지혜;김미경;주재원;한지숙;박정현

  • Published : 2006.05.30
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Abstract

Background: Green-tea polyphenol (GTP) is a well known antioxidant with favorable effect on blood glucose and lipid level in animal models. We were to investigate the effects of GTP on plasma glucose, lipid and antioxidant systems in patients with type 2 diabetes. Methods: We recruited non-complicated type 2 diabetic patients with stable glycemic control by oral hypoglycemic agents. Subjects were randomly assigned to GTP group or placebo group for 12 weeks. Fasting plasma glucose (FPG), HbA1c, C-peptide, lipid levels, liver function test, renal function test, urine microalbumin, malondialdehyde (MDA), superoxide dismutase (SOD) and glutathione peroxidase (GSHPx) activities were measured at baseline and after 12 weeks of treatment. Results: At baseline, there were no significant differences in age, body mass index, duration of diabetes, dietary status, HbA1c, total cholesterol, LDL cholesterol, and HDL cholesterol levels between GTP and placebo group. However, FPG levels and triglyceride levels were significantly different between GTP and placebo group at baseline. In both of GTP and placebo group, there were no significant change after 12 weeks of treatment in FPG, HbA1c, total cholesterol, LDL cholesterol, triglyceride, levels of MDA, and GSHPx activities. SOD activities significantly increased after 12 weeks of treatment in both of GTP and placebo group. The increase of SOD activities were significantly higher in GTP group than in placebo group (P = 0.01). Conclusions: Supplementation of green tea polyphenol increased antioxidant activity in type 2 diabetic patients. The effect on plasma glucose and lipid level was not significant but should be confirmed in further large scaled studies.

연구배경: 녹차 폴리페놀은 동물 모델에서 항산화 효과를 보이며 혈당 및 혈중 콜레스테롤 수치의 호전을 보인다. 녹차 폴리페놀이 제2형 당뇨병환자에서 혈당, 지질 및 항산화 체계에 미치는 영향을 살펴보았다. 방법: 경구혈당강하제 투여로 혈당이 안정되게 조절되고 합병증이 없는 제2형 당뇨병환자를 실험군과 대조군으로 무작위 배정하였다. 12주간 실험군에게 녹차 폴리페놀을 대조군에게는 위약을 각각 투여하였다. 투약 전후에 공복혈당, 당화혈색소, C-펩티드, 지질, 간 및 신장기능검사를 시행하였으며, 항산화의 지표로 MDA 농도, GSHPx 활성, SOD 활성을 측정하였다. 결과: 실험군 (21명), 대조군 (17명) 간에 투약 전에 연령, 당뇨병의 유병기간, 체질량지수, 식습관, 영양상태, 당화혈색소, 총 콜레스테롤, LDL 콜레스테롤, HDL 콜레스테롤 수치는 유의한 차이가 없었으나 공복혈당과 중성지방 수치는 차이를 보였다. 실험군과 대조군 모두에서 투약 전후에 공복혈당, 당화혈색소, 총 콜레스테롤, LDL 콜레스테롤, 중성지방 수치, MDA 농도와 GSHPx 활성은 유의한 변화가 없었다. 실험군과 대조군 모두에서 투약 전후에 SOD 활성이 증가하였는데 실험군에서 대조군보다 증가 정도가 유의하게 높았다. 결론: 본 연구는 녹차 폴리페놀을 제2형 당뇨병환자에게 12주간 투여하면 항산화 상태의 개선을 보일 것이라는 가능성을 제시하였다. 녹차 폴리페놀은 혈당 조절, 혈중 지질에 유의한 영향을 미치지 않았으나, 이는 향후 대규모 연구를 통한 검증이 필요할 것이다.

Keywords

References

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