In a lab study using mouse pancreatic beta‑cell lines, adding ghrelin or its analogue GHRP‑6 helped the cells survive when they were overloaded with sugar and fat. The peptides boosted insulin production and blocked a stress pathway (IRE1/JNK) that normally leads to cell death.

Glucose and fatty acid overload-induced glucolipid toxicity of pancreatic β-cells is associated with the development of diabetes. Endoplasmic reticulum stress (ERS) plays an essential role in this process. Ghrelin, a peptide secreted by the pancreas, negatively correlates with oxidative stress. The study aimed to investigate ghrelin's role in glycolipid-induced β-cell dysfunction and its possible mechanism. Mouse insulinoma β-cell, NIT-1 cells, were stimulated with high fat and high glucose to induce glucolipid toxicity. High fat and high glucose-induced NIT-1 cells were treated with acylated ghrelin (AG) or [d-Lys3]-growth hormone releasing peptide (GHRP)-6. Flow cytometry and Cell Counting Kit-8 (CCK-8) assay were performed to assess apoptosis and cell viability. The protein expression related to apoptosis, inositol-requiring kinase 1 (IRE1)/c-Jun N-terminal kinase (JNK) signaling, and ERS were investigated using western blot. Enzyme-linked immunosorbent assay (ELISA) was adopted to examine insulin's synthesis and secretion levels. Ghrelin treatment improved cell viability while inhibiting cell glucolipotoxicity-induced NIT-1 cell apoptosis. Ghrelin can promote the synthesis and secretion of insulin in NIT-1 cells. Mechanistically, ghrelin attenuates ERS and inhibits the IRE1/JNK signaling pathway in NIT-1 cells induced by glucolipotoxicity. Ghrelin improves β-cellular dysfunction induced by glucolipotoxicity by inhibiting the IRE1/JNK pathway induced by ERS. It could be an effective treatment for β-cellular dysfunction.