Background: This study examined the hypoglycemic and kidney protective effect of black ginseng in streptozotocin-induced diabetic mice. Methods and Results: Diabetes was induced by treating mice with streptozotocin (STZ) for four weeks. In vivo studies were performed in order to investigate the hypoglycemic effect of the black ginseng prosapogenin (GBG05-FF) extract. The body weight and blood glucose level were measured. Moreover, after the mice were sacrificed, the kidneys were isolated and histological changes were observed with hematoxylin and eosin staining. Blood urea nitrogen and creatinine levels were also measured. The results showed that administration of black ginseng increased body weight. Compared to blood glucose levels in STZ mice, blood glucose levels were reduced by 48% in STZ mice supplemented with 300 ㎎/㎏ of black ginseng, and by 69% in STZ mice supplemented with 900 ㎎/㎏. Furthermore, histopathological examination of STZ mouse kidneys revealed, changes in the kidneys, epithelial cell damages, inflammatory cell infiltration and glomerulus hypertrophy. However, a significant reduction of glomerular water droplets (indicative of glomerulus hypertrophy) was observed in the kidneys of STZ mice supplemented with black ginseng extract. Conclusions: These results suggest that black prosapogenin (GBG05-FF) ginseng extract has a significant hypoglycemic effect and can be used as an anti-diabetic substance and renal protective agents as part of dietary supplements or novel drugs.

The aim of the present study was to evaluate the beneficial effects of Eriobotryae Folium on diabetic improvement through oxidative stress and inflammation in the liver of type 2 diabetic db/db mice. Eriobotryae Folium extract (100 or 200 mg/kg body weight, p.o) was administrated everyday for 3 weeks. And then, its effect was assessed on comparison with vehicle-treated db/db and non-diabetic m/m mice. Serum glucose and hepatic tissue biochemical factors and protein expression related with oxidative stress and inflammation such as reactive oxygen species (ROS) and nicotinamide adenine dinucleotide phosphate (NADPH) oxidase were measured. As a result, the administration of Eriobotryae Folium decreased body and liver weight, food intake in vehicle-treated db/db. Also, serum glucose was lowered by Eriobotryae Folium treatment. Eriobotryae Folium administration decreased oxidative stress through the down-regulation of ROS and NADPH oxidase subunit proteins, NOX-4 and p47 phox .Moreover,theincreaseofinflammatoryproteinssuchasinduciblenitricoxidesynthase(iNO S),cyclooxygenase-2(COX-2),tumornecrosisfactoralpha(TNF-α), interleukin-6 (IL-6) on vehicle-treated db/db were significantly decreased through down-regulation nuclear factor-kappa B (NF-κB) and activator pretoein-1 (AP-1) via reduction of oxidative stress. Therefore, hepatic functional parameters such as alanine aminotransferase, aspartate aminotransferase significantly decreased. In conclusion, Eriobotryae Folium extract could have hepato-protective effect through down-regulation of abnormal NADPH oxidase subunit and the oxidative stress in type 2 diabetic db/db mice.

본 연구에서는 비 상품 부추의 산업적 활용의 활성화를 위해 제 2형 당뇨모델인 db/db 마우스에서 부추 추출물과 부추 발효물에 대한 항당뇨 효과를 조사하였다. 부추 발효 물 제조를 위한 균주선발을 위해 L. acidophilus, L. plantarum, L. casei을 접종하여 배양시킨 부추 추출물(부추 발효물)에 대한 전자공여능을 측정한 결과, L. acidophilus, L. plantarum 부추 발효물은 활성이 증가되었으나 L. plantarum 접종한 부추 발효물의 superoxide radical 소거능 은 부추 추출물의 0.6배 수준으로 감소하였다. L. plantarum 와L. casei 균주를 접종한 부추 발효물의 superoxide radical 소거능은 부추 추출물과 유사한 수준을 나타내었다. 따라 서L. plantarum과L. casei를 이용하여 발효한 부추 발효물 과 부추 추출물을 제2형 당뇨질환 동물모델인db/db mice에 두 가지 농도구간으로(저농도 : 200 mg/kg, 고농도 : 400 mg/kg) 경구 투여한 후, 항당뇨 효능을 평가하였다. 체중 및 식이섭취량을 측정한 결과, 저농도 부추 발효물을 투여 하였을 때, 식이섭취량의 변화 없이 체중증가량이 유의적 으로 감소되는 것을 확인할 수 있었다(p<0.05). 혈당증가량 과 혈청 내 insulin 함량은 고농도 부추 추출물을 투여하였을 때, 유의적으로 감소되었고, 부추 발효물을 투여한 군에서 도 감소되는 경향을 나타내었다(p<0.05). 경구 당 부하검사 결과에서도 고농도의 부추 추출물 및 부추 발효물을 투여한 군에서 포도당 내성 효과가 개선되는 것으로 나타났다. 당 뇨병에 의해 감소된 혈청 내 GLP-1 농도는 고농도 부추 추출물 및 고농도의 부추 발효물 투여로 인해 증가되었으며 이상의 결과들은 부추 추출물 및 부추 발효물이 GLP-1 분비 를 증가시켜 insulin 저항성을 개선시킬 수 있음을 나타낸다. 비록 본 연구결과에서 제2형 당뇨질환에 대한 항당뇨 효능 은 부추 추출물이 부추 발효물 보다 더 효과적인 것으로 나타났으나, 두가지 유산균으로 혼합발효한 부추 발효물은 부추 추출물과 유사한 수준의 항당뇨 효능을 보임과 동시에 제2형 당뇨병으로 인한 체중증가도 감소시킬 수 있어 비만 을 동반하는 제2형 당뇨병의 예방과 개선을 위한 기능성 소재로 활용될 수 있을 것이라 사료된다.