著者
Stella Amarachi Ihim Yukiko K. Kaneko Moe Yamamoto Momoka Yamaguchi Toshihide Kimura Tomohisa Ishikawa
出版者
The Pharmaceutical Society of Japan
雑誌
Biological and Pharmaceutical Bulletin (ISSN:09186158)
巻号頁・発行日
vol.46, no.4, pp.630-635, 2023-04-01 (Released:2023-04-01)
参考文献数
31

The improvement of type 2 diabetes mellitus induced by naturally occurring polyphenols, known as flavonoids, has received considerable attention. However, there is a dearth of information regarding the effect of the trihydroxyflavone apigenin on pancreatic β-cell function. In the present study, the anti-diabetic effect of apigenin on pancreatic β-cell insulin secretion, apoptosis, and the mechanism underlying its anti-diabetic effects, were investigated in the INS-ID β-cell line. The results showed that apigenin concentration-dependently facilitated 11.1-mM glucose-induced insulin secretion, which peaked at 30 µM. Apigenin also concentration-dependently inhibited the expression of endoplasmic reticulum (ER) stress signaling proteins, CCAAT/enhancer binding protein (C/EBP) homologous protein (CHOP) and cleaved caspase-3, which was elevated by thapsigargin in INS-1D cells, with peak suppression at 30 µM. This was strongly correlated with the results of flow cytometric analysis of annexin V/propidium iodide (PI) staining and DNA fragmentation analysis. Moreover, the increased expression of thioredoxin-interacting protein (TXNIP) induced by thapsigargin was remarkably reduced by apigenin in a concentration-dependent manner. These results suggest that apigenin is an attractive candidate with remarkable and potent anti-diabetic effects on β-cells, which are mediated by facilitating glucose-stimulated insulin secretion and preventing ER stress-mediated β-cell apoptosis, the latter of which may be possibly mediated by reduced expression of CHOP and TXNIP, thereby promoting β-cell survival and function.
著者
Yukiko K. Kaneko
出版者
The Pharmaceutical Society of Japan
雑誌
Biological and Pharmaceutical Bulletin (ISSN:09186158)
巻号頁・発行日
vol.46, no.5, pp.640-646, 2023-05-01 (Released:2023-05-01)
参考文献数
47

Although diabetes is associated with an increased risk of various diseases, including cancer and infectious diseases, no definitive cure has yet been found. Long-term treatment for blood glucose control significantly reduces the QOL. Pancreatic β-cells are the only cells that can lower blood glucose levels by secreting insulin. Therefore, maintaining insulin-secreting β-cells is crucial in preventing the progression of diabetes and improving the QOL. We have investigated the mechanisms for the regulation of insulin secretion, the prevention of β-cell apoptosis, and the increase in β-cell mass. In particular, we have elucidated the involvement of type I diacylglycerol kinase (DGK) in the regulation of insulin secretion and the effects of nitric oxide (NO) signaling and natural products in suppressing β-cell death. In addition, we have elucidated the function of DGKδ as a suppressor of β-cell proliferation. This review introduces the findings of our study leading to development of novel anti-diabetic therapeutics that targets pancreatic β-cells.