Pair Fed 흰쥐에 있어서 녹차의 항증체, 지질개선 및 항산화 효과 = Effects of Green Tea on Weight Gain, Plasma and Liver Lipids and Lipid Peroxidation in Pair Fed Rats

국문 초록 (Abstract)

본 연구에서 pair feeding함으로서 사료 섭취량이 체중이나 지단백 대사에 미칠 요인을 제거한 상태에서 녹차분말이나 녹차추출물이 갖는 항 비만효과나 지질 강하효과를 비교조사하였다.
녹차분말이나 추출물에서 증체 억제효과를 보였는데 이는 녹차성분이 소장에서의 지방흡수를 억제하거나 지방산화를 촉진하고 대사율을 올려 열량소비를 증가시킨다는 기존 연구결과와 이해를 같이 하는데, 예비실험에서 사료섭취량 자체가 억제됨을 감안 할 때 녹차 추출물이나 분말의 항비만 효과에 대해서 긍정적이다. 본 연구에서 녹차 추출물의 높은 콜레스테롤 흡수 억제력에도 불구하고 녹차의 콜레스테롤 강하효과는 나타나지 않았는데 이는 체 콜레스테롤 pool size에 강한 homeostasis 기질이 작용한 것이라고 생각할 수 있다.
식이 콜레스테롤과 지방의 흡수억제에 있어서 녹차분말과 녹차 추출물의 장내 유용성과 체 콜레스테롤의 합성과 담즙 생성에 있어서 EGCG를 포함한 차 카테킨 작용기전을 이해하기 위해서 보다 많은 연구가 필요하리라 생각된다. 녹차 분말과 추출물은 항산화 지표에도 정도에 다소 차이가 있으나 긍정적인 효과를 보였는데 녹차 카테킨은 수용성으로 bioavailability가 비교적 높은 polyphenol계 항산화 물질로서 녹차 잎의 건조중량 50% 이상이 카테킨이고 이중 80% 이상이 catechin gallate 형태로 강한 항산화 효력을 지닌 것으로 나타나 있다.
노화를 활성산소에 의한 세포의 손상과정이라 볼 때 식품으로서 녹차는 매우 중요한 입지에 있다. 차로 마시는 녹차의 섭취방법에서 분말이나 추출물로 섭취방법을 다양화하고 있는데 분말과 추출물의 영양적 효과를 비교해 볼 때 유리 (free)된 카테킨 형태로 추출물이 유리할 수 있지만 녹차분말이 식품으로서의 높은 선호도와 함께 HDL-콜레스테롤을 증가시키는 효과가 있다면 분말차의 섭취도 좋은 방법이다. 음료로서 따져 볼 때 일회 분량 2 g의 녹차를 3회 우려 마시는 경우 이로부터 섭취할 수 있는 항산화물질은 EGCG기준으로 109~147 ㎎정도이고 이를 비타민 C로 환산하는 경우 142~168 ㎎이다.31) 천연의 항산화 물질을 자연스럽게 섭취하는 방법으로서 차의 음용을 생활화하는 것은 비만이나 퇴행성 또는 노화관련 질환의 예방차원에서 바람직하리라 본다.

다국어 초록 (Multilingual Abstract)

We compared antiobese, hypocholesterolemic, antiplatelet and antioxidant effect of 10% green tea powder and 3% green tea extract in rats pair fed 5% cholesterol diets. The final body weight was decreased significantly compared with the control (p ＜ 0.05). Plasma and liver total cholesterol were lower in group of green tea powder or extract, but not statistically different. HDL cholesterol was increased significantly in group of green tea powder compared with the control or green tea extract (p ＜< 0.05). Plasma triglyceride was significantly decreased in group of green tea extract compared with green tea powder, and green tea powder compared with the control respectively (p ＜ 0.05). Liver triglyceride was significantly decreased in group of green tea powder or green tea extract compared with the control (p ＜ 0.01). Platelet aggregations in the maximum and initial slope were not different among groups. Hemolysis was significantly lower in group of green tea powder compared with the control (p ＜ 0.05). Plasma TBARS production was decreased in group of green tea extract compared with the control (p ＜ 0.05). Na passive leak in intact cells was not different, but Na leak in AAPH treated cell was significantly decreased in group of green tea powder than the control (p ＜ 0.05). The leak increase (△Na Leak) after AAPH treatment was significantly decreased in groups of green tea powder and extract compared with the control (p ＜ 0.05). Isotope excretion after ¹⁴C-cholesterol ingestion was significantly increased in group of green tea extract compared with the control or the green tea powder (p ＜ 0.05). Consumption of green tea in powder or extract may give beneficial effects in weight control and plasma lipid profiles, impeding metabolic syndrome. More studies are needed to clarify what component of green tea and what mechanism are involved in antiobese and hypolipedemic actions of green tea.

목차 (Table of Contents)

• ABSTRACT
• 서론
• 재료 및 방법
• 결과
• 고찰
• 요약
• Literature cited

참고문헌 (Reference)

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