BIOENERGETIC REQUIREMENTS FOR A BIOARTIFICIAL PANCREAS

生物人工胰腺有望对血糖水平进行生理控制，有效治疗1型糖尿病。鉴于胰岛的供应不足，开发适合于这种装置的替代细胞系是必要的。转化细胞是一个可行的选择，尽管它们的生物能量机制可能效率低下。由于生物能量学在胰岛素分泌中起作用，确定对胰岛素分泌至关重要的生物能量因子对于选择合适的细胞系纳入生物人工胰腺可能很重要。本研究将研究被包裹的转化胰岛素瘤细胞的培养，并确定ATP和复变途径对其分泌胰岛素的能力的影响，以响应外部葡萄糖刺激。13C和31P数据的核磁共振光谱分析将提供能量代谢与胰岛素分泌之间耦合的非侵入性定量评估，而非核磁共振分析将获得葡萄糖和氧气消耗率，以及乳酸，NH4+和胰岛素产生率，以提供代谢谱。对TCA循环、逆转途径和氧化磷酸化的特定抑制剂的施用，将有助于确定胰岛素分泌起始的关键因素。这些知识将有助于合理设计和选择产生胰岛素的细胞。

Bioartificial pancreata promise physiological control of blood glucose levels, effectively treating Type I diabetes mellitus. Given the short supply of islets, development of alternative cell-lines appropriate for use in such devices is necessary. Transformed cells are a viable option, though their bioenergetic machinery may be inefficient. Because bioenergetics plays a role in the secretion of insulin, determining bioenergetic factors critical to insulin secretion may be important in selecting appropriate lines for inclusion into a bioartificial pancreas. This proposal will study cultures of entrapped transformed insulinoma cells and determine the impact of ATP and anaplerotic pathways on their ability to secrete insulin in response to an external glucose stimulus. NMR spectroscopic analysis of 13C and 31P data will provide a non-invasive quantitative assessment of the coupling between energy metabolism and insulin secretion, while non-NMR assays will derive glucose and oxygen consumption rates, as well as lactate, NH4+ and insulin production rates to provide a metabolic profile. Administration of specific inhibitors of the TCA cycle, anaplerotic pathways and oxidative phosphorylation, will aid in identifying factors critical to the initiation of insulin secretion. This knowledge will aid in the rational design and selection of insulin-producing cells.