Effects of metformin on compensatory pancreatic {beta}-cell hyperplasia in mice fed a high-fat diet

In this study, we investigated the impacts of treatment with metformin on pancreatic β-cells in a mouse model fed a high-fat diet (HFD), which triggers adaptive β-cell replication. An 8-wk treatment with metformin improved insulin resistance and suppressed the compensatory β-cell hyperplasia induced by HFD-feeding. In contrast, the increment in β-cell mass arising from 60 wk of HFD feeding was similar in mice treated with and those treated without metformin. Interestingly, metformin suppressed β-cell proliferation induced by 1 wk of HFD feeding without any changes in insulin resistance. Metformin directly suppressed glucose-induced β-cell proliferation in islets and INS-1 cells in accordance with a reduction in mammalian target of rapamycin phosphorylation. Taken together, metformin suppressed HFD-induced β-cell proliferation independent of the improvement of insulin resistance, partly via direct actions.

Source: AJP: Endocrinology and Metabolism - September 11, 2017 Category: Endocrinology Authors: Tajima, K., Shirakawa, J., Okuyama, T., Kyohara, M., Yamazaki, S., Togashi, Y., Terauchi, Y. Tags: Research Article Source Type: research