The protective effects and genetic pathways of thorn grape seeds oil against high glucose-induced apoptosis in pancreatic β-cells

BACKGROUND: Excessive apoptosis of β-cell is closely related to diabetes mellitus. Chronic exposure to high glucose causes β-cell dysfunction and apoptosis in diabetes. Thorn grape (Vitis davidii Foex.) has been used to treat diabetes in Traditional Chinese medicine for many years. In our previous research, thorn grape seeds oil (TGSO) showed promising anti-diabetic effects in animal models. However, it is unknown whether TGSO played an anti-apoptotic role in the anti-diabetic effects and the mechanism regarding signal transduction pathway is unclear either. METHODS: The rattus pancreatic β-cell line RIN-m5F was treated with/without TGSO which was extracted by supercritical carbon dioxide (CO(2)) fluid extraction and analyzed by Gas Chromatography/Mass Spectrometry (GC/MS). Cell apoptosis was detected by fluorescence activated cell sorting (FACS), insulin secretion was assayed by Enzyme-Linked Immunosorbent Assay (ELISA), and the apoptosis-related genes expressions were evaluated by quantitative Reverse Transcription Polymerase Chain Reaction (qRT-PCR). RESULTS: TGSO, containing 87.02% unsaturated fatty acids (UFAs), significantly reduced pancreatic β-cell apoptosis and protected the insulin secretion impaired by high glucose. The expressions of pro-apoptotic genes such as iNOS, Caspase-3, ATF-3, JNK, p38 and Fas were down-regulated while the anti-apoptotic genes Akt and Bcl-2/Bax were up-regulated. CONCLUSIONS: The results indicated that TGSO protected β-cells from high glucose-induced apoptosis and its protective activity may be linked to mitochondrial pathway, endoplasmic reticulum (ER) stress pathway and Fas signal pathway, which implied that TGSO might be an effective complementary or alternative medicine to reduce β-cell apoptosis and dysfunction.