Effect of African Mango (Irvingia gabonesis, IGOB 131^TM) Extract on Glucose Regulation in STZ-Induced Diabetes

Streptozotocin으로 유발한 당뇨동물 모델에서 아프리칸 망고 추출물의 혈당 조절 효과

This study investigated the regulatory effects of African mango (Irvingia gabonesis, IGOB $131^{TM}$) extract on blood glucose level in streptozotocin (STZ)-induced diabetic rats. Experimental groups were treated with two different doses of IGOB $131^{TM}$ (1% and 2% in each AIN93G supplement) for 5 weeks [4 weeks pre-treatment and 1 week post-STZ treatment (60 mg/kg body weight)]. STZ-induced diabetic rats showed significantly reduced body weight gain compared to normal control (NC). Oral glucose tolerance test (OGTT) was measured using glucose oxidase-peroxidase reactive strips. The area of under the curve for the glucose response from OGTT in STZ-induced diabetic rats was higher than that of NC rats, and there was a significant difference between the DM and the IGOB $131^{TM}$-treated groups. Serum glucose levels after sacrifice were significantly lower in the IGOB $131^{TM}$ group than the DM group. However, there was no statistical difference between low- and high-dose treatments. Serum insulin levels increased by 234.4% and 175.9%, respectively, upon treatment with IGOB $131^{TM}$. Serum lipid profiles were not significantly different among the experimental groups. The tested samples had no effects on serum levels of lipid profiles (triglyceride, total cholesterol, low density lipoprotein/very low density lipoprotein-cholesterol, high density lipoprotein-cholesterol). These results suggest that IGOB $131^{TM}$ is able to ameliorate diabetes by reducing serum glucose levels that may result from increased insulin levels.

본 연구는 당뇨유발모델 쥐에서 아프리칸 망고(Irvingia gabonesis, IGOB $131^{TM}$) 추출물의 혈당 조절 효과를 알아보기 위해 SD계 수컷 흰쥐에 IGOB $131^{TM}$ 1%, IGOB $131^{TM}$ 2%(IGOB $131^{TM}$ 353 mg/kg body weight, IGOB $131^{TM}$ 706 mg/kg body weight)와 pinitol을 5주간 매일 강제 경구 투여하였다. 그리고 streptozotocin을 복강 주사하여 당뇨를 유발시킨 후 경구 당부하 검사(OGTT)를 실시하였다. 정상군에 비해 당뇨 유발군(DM, pinitol, IGOB $131^{TM}$ 1%, IGOB $131^{TM}$ 2%)의 체중 증가는 유의적으로 감소하였고, 당뇨 유발군 간의 유의적인 차이는 나타나지 않았다. 경구 당부하 검사 결과에서 DM군이 정상군에 비해 유의적으로 높았고, pinitol군, IGOB $131^{TM}$ 1%, IGOB $131^{TM}$ 2%군은 DM에 비해 각각 39.70%, 33.00%, 29.67% 유의적으로 감소하였다. 혈청 glucose 농도는 정상군에 비해 당뇨 유발군에서 유의적으로 높게 나타났고, pinitol, IGOB $131^{TM}$ 1%, IGOB $131^{TM}$ 2%군은 DM에 비해 유의적으로 감소하였다. 또한 혈청 insulin 농도는 정상군에 비해 당뇨 유발군에서 유의적으로 낮게 나타났고, pinitol, IGOB $131^{TM}$ 1%, IGOB $131^{TM}$ 2%군은 DM에 비해 유의적으로 증가한 것으로 나타났다. 따라서 아프리칸 망고 추출물이 STZ 유도 당뇨쥐의 혈청 insulin 함량을 개선시켜 혈청 glucose를 감소하는 효과가 있는 것으로 사료된다.