中国病理生理杂志2012，Vol.28Issue(7)：1281-1286,6.DOI:10.3969/j.issn.1000-4718.2012.07.024
L-carnosine 对 NIT-1胰岛细胞的影响及机制
Effects of L-carnosine on NIT-1 islet cells
摘要
Abstract
AIM: To investigate the protective effect of L — carnosine on insulin secretion, proliferation and ap-optosis of (3 — cells impaired by high glucose. METHODS: NIT — 1 cells were pre — treated with glucose at concentrations of 11. 1 mmol/L ( control level ) and 33.3 mmol/L ( high level ) for 72 h, and then the cells were stimulated with various concentrations of glucose (0,5 and 25 mmol/L ) and/or L — carnosine (0,1 and 20 mmol/L ). The level of insulin in the medium was measured by radioimmunoassay. To detect the effect of L — carnosine on proliferation and apoptosis, NIT — 1 cells were divided into 4 groups according to different culture conditions for 72 h: group C ( with 11.1 mmol/L glucose ), group H ( with 33. 3 mmol/L glucose ), group H + A ( with 33. 3 mmol/L glucose + 1 mmol/L L - carnosine ) and group H + B ( with 33. 3 mmol/L glucose + 20 mmol/L L - carnosine ). Proliferous or apoptotic cells were identified by BrdU labeling and flow cytometry ( labeling with annexin V - FITC/PI ), respectively. Total RNA was extracted and the mRNA expression of caspase - 3 and bcl - 2 was measured by RT - PCR. The caspase - 3 activity was also checked by fluorometric assay kit. RESULTS: The insulin in high - level glucose group was lower than that in control - level glucose group. L -carnosine at concentration of 20 mmol/L notably increased the insulin secretion of the cells pre - treated with glucose at control level or high level. The proliferation and apoptosis were both increased in group H compared with group C, but the total cell counts declined because the apoptotic rate was higher than the proliferation rate. L - carnosine at concentration of 1 mmol/L significantly increased the proliferation rate and decreased the apoptotic rate. The mRNA level of caspase — 3 was decreased and the mRNA level of bcl - 2 was increased after the cells were treated with L - carnosine at concentration of 1 mmol/L. L — carnosine at concentrations of both 1 mmol/L and 20 mmol/L significantly decreased the caspase — 3 activity. CONCLUSION: L — carnosine at high level directly stimulates insulin secretion in NIT — 1 cells, and L — carnosine at normal level promotes the cell proliferation and inhibits apoptosis induced by high concentration of glucose. Caspsase — 3 and Bcl - 2 may be partly involved in this process.关键词
肌肽/葡萄糖/胰岛素/细胞凋亡/NIT-1细胞Key words
Carnosine/ Glucose/ Insulin/ Apoptosis/ NIT - 1 cells分类
医药卫生引用本文复制引用
周莉莉,桂书彦,杨雁,袁刚..L-carnosine 对 NIT-1胰岛细胞的影响及机制[J].中国病理生理杂志,2012,28(7):1281-1286,6.基金项目
国家自然科学基金资助项目(No.81100582) （No.81100582）
