• 대한본초학회지
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• 제30권6호
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• pp.7-15
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• 2015

Objectives : Rosa laevigata Michx. has been used for the treatment of renal disease in traditional Korean medicine. In this study, we investigated cytoprotective effect of R. laevigata water extract (RLE) against oxidative stress induced by arachidonic acid (AA) + iron.Methods : To evaluate the protective effects of RLE against AA + iron-induced oxidative stress in HepG2 cell, cell viability and changes on apoptosis-related proteins were assessed by MTT and immunoblot analyses. The effects of RLE on reduced glutathione level, production of reactive oxygen species and mitochondrial membrane potential were also monitored. Furthermore, to verify underlying molecular mechanism, NF-E2-related factor 2 (Nrf2) was examined by immunoblot analysis. Additionally, Nrf2 transactivation and its downstream target genes expression were also determined by reporter gene and realtime RT-PCR analyses.Results : RLE pretreatment (30-300 μg/ml) prevented cells from AA + iron-mediated cell death in a concentration dependent manner. In addition, 100 μg/ml RLE inhibited AA + iron-induced glutathione depletion, reactive oxygen species production and mitochondrial dysfunction. RLE accumulated nuclear Nrf2 and also transactivated Nrf2, which was evidenced by antioxidant response element- and glutathione S-transferase A2-driven luciferase activities and mRNA level of glutamate-cysteine ligase catalytic subunit, NAD(P)H:quinone oxidoreductase 1 and sestrin 2. Moreover, protective effect of RLE against AA + iron was abolished in Nrf2 knockout cells.Conclusions : These results indicate that RLE has the ability to protect hepatocyte against oxidative stress through Nrf2 activation.

• 대한임상독성학회지
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• 제17권2호
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• pp.58-65
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• 2019

Purpose: Alpha-amanitin induces potent oxidative stress and apoptosis, and may play a significant role in the pathogenesis of hepatotoxicity. This study examined the mechanisms of α-amanitin-induced apoptosis in vitro, and whether green tea extract (GTE) offers protection against hepatic damage caused by α-amanitin (AMA) induced apoptosis in vivo. Methods: The effects of GTE and SIL on the cell viability of cultured murine hepatocytes induced by AMA were evaluated using an MTT assay. Apoptosis was assessed by an analysis of DNA fragmentation and caspase-3. In the in vivo protocol, mice were divided into the following four groups: control group (0.9% saline injection), AMA group (α-amanitin 0.6 mg/kg), AMA+SIL group (α-amanitin and silibinin 50 mg/kg), and AMA+GTE group (α-amanitin and green tea extract 25 mg/kg). After 48 hours of treatment, the hepatic aminotransferase and the extent of hepatonecrosis of each subject was evaluated. Results: In the hepatocytes exposed to AMA and the tested antidotes, the cell viability was significantly lower than the AMA only group. An analysis of DNA fragmentation showed distinctive cleavage of hepatocyte nuclear DNA in the cells exposed to AMA. In addition, the AMA and GTE or SIL groups showed more relief of the cleavage of the nuclear DNA ladder. Similarly, values of caspase-3 in the AMA+GTE and AMA+SIL groups were significantly lower than in the AMA group. The serum AST and ALT levels were significantly higher in the AMA group than in the control and significantly lower in the AMA+GTE group. In addition, AMA+GTE induced a significant decrease in hepatonecrosis compared to the controls when a histologic grading scale was used. Conclusion: GTE is effective against AMA-induced hepatotoxicity with its apoptosis regulatory properties under in vitro and in vivo conditions.

• 생명과학회지
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• 제27권8호
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• pp.909-918
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• 2017

본 연구는 아이스플랜트의 생리활성을 향상시키고, 식생활에서의 활용가능성을 높이기 위하여 물김치 형태로 발효시켰으며, 아이스플랜트의 성분 및 몇 가지 생리활성을 발효 전과 비교하였다. 물김치 침지액의 pH는 발효 6일째까지 계속해서 낮아졌으며, lactic acid의 생성량은 발효 4일째에 가장 많았다. 아이스플랜트 물김치 건더기 중의 D-pinitol은 발효 전 $4.196{\pm}0.096mg/g$에서 6일째에는 $3.843{\pm}0.116mg/g$으로 감소하였다. 그러나 myo-inositol과 D-chiro-inositol은 각각 발효 전 $0.453{\pm}0.022$와 $2.815{\pm}0.008mg/g$에서 6일째에 $0.630{\pm}0.029$와 $4.117{\pm}0.096mg/g$으로 증가하였다. 아이스플랜트 추출물의 DPPH, ABTS radical 소거활성 및 FRAP 활성은 대체로 발효 후에 높게 나타나 유사한 경향이었으며, 1 mg/ml의 농도로 처리하였을 때 각각 발효 5일째($79.09{\pm}0.69%$), 4일째($87.55{\pm}1.21%$) 및 6일째($78.72{\pm}0.99%$)에 가장 높았다. Lipid/MA assay에 의한 항산화 활성도 대체로 발효 후에 높게 나타나 유사한 경향이었으며, 추출물을 $500{\mu}g/ml$ 처리하였을 때, 발효 4일째에 가장 높은 활성($64.65{\pm}1.63%$)을 나타났으며, 발효 5, 6일째에는 낮아지는 경향이었다. 아이스플랜트 추출물의 t-BHP, $H_2O_2$ 및 ethanol에 의하여 손상된 BNL CL.2 세포의 생존율은 각각 $14.19{\pm}0.98$, $13.80{\pm}2.25$ 및 $25.89{\pm}2.90%$이었으나, 추출물을 $200{\mu}g/ml$의 농도로 처리하였을 경우, 각각 발효 6일째에 $50.07{\pm}4.85%$, 2일째에 57.06% 및 4일째에 $66.06{\pm}1.36%$의 세포생존율을 나타내어 간세포가 회복되고 있음을 알 수 있었다. 그러나 발효 후에 간세포 보호효과가 뚜렷이 증가하지는 않았다. ${\alpha}-Glucosidase$ 저해활성은 모든 실험군에서 $83.52{\pm}2.69{\sim}92.79{\pm}2.16%$로 상당히 높게 나타났으며, 발효기간이 경과함에 따라 조금씩 증가하였다. 한편 ${\alpha}-Amylase$ 저해활성은 전체적으로 $52.64{\pm}3.26{\sim}57.56{\pm}1.21%$로 나타났으며 발효 전후에 뚜렷한 차이가 없었다. 이와 같은 결과로 볼 때, 아이스플랜트의 물김치 발효기간은 4~5일이 적정할 것으로 생각되었다. 한편 발효에 의한 기능성은 항산화효과를 제외한 간세포보호 및 ${\alpha}-Glucosidase$, ${\alpha}-Amylase$ 저해활성은 전체적으로 소폭 향상에 그쳤다. 따라서 이러한 결과를 바탕으로 발효 등 다양한 가공방법이 개발되어, 향후 아이스플랜트의 소비촉진의 계기가 되기를 기대한다.