Beneficial Effect of Jojoba Seed Extracts on Hyperglycemia-Induced Oxidative Stress in RINm5f Beta Cells

• Published in: Nutrients Vol. 10; no. 3; p. 384
• Main Authors: Belhadj, Sahla, Hentati, Olfa, Hamdaoui, Ghaith, Fakhreddine, Khaskhoussi, Maillard, Elisa, Dal, Stéphanie, Sigrist, Séverine
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 20.03.2018; MDPI
• Subjects: Acetonitriles - isolation & purification; Acetonitriles - pharmacology; Animals; Antioxidants; Antioxidants - isolation & purification; Antioxidants - pharmacology; Beta cells; Caspase; Caspase 3 - metabolism; Caspase-3; Cell Line, Tumor; Cell Survival - drug effects; Cyclohexanes - isolation & purification; Cyclohexanes - pharmacology; Diabetes mellitus; Dose-Response Relationship, Drug; Fructose; Fructose - toxicity; Glucosides - isolation & purification; Glucosides - pharmacology; Hyperglycemia; Insulin; Insulin - metabolism; Insulin Secretion; Insulin-Secreting Cells - drug effects; Insulin-Secreting Cells - metabolism; Insulin-Secreting Cells - pathology; jojoba; Magnoliopsida - chemistry; NADPH Oxidases - metabolism; NF-E2-Related Factor 2 - metabolism; Nrf2; Oxidation resistance; Oxidative stress; Oxidative Stress - drug effects; p22phox; Phytotherapy; Plant Extracts - isolation & purification; Plant Extracts - pharmacology; Plants, Medicinal; Polyphenols; Rats; Reactive Oxygen Species - metabolism; RINm5f; Secretion; Seeds; Seeds - chemistry; Signal transduction; Signal Transduction - drug effects; Simmondsin; RINm5f; p22phox; Nrf2; jojoba; oxidative stress; caspase-3
• ISSN: 2072-6643; 2072-6643
• DOI: 10.3390/nu10030384

Hyperglycemia occurs during diabetes and insulin resistance. It causes oxidative stress by increasing reactive oxygen species (ROS) levels, leading to cellular damage. Polyphenols play a central role in defense against oxidative stress. In our study, we investigated the antioxidant properties of simmondsin, a pure molecule present in jojoba seeds, and of the aqueous extract of jojoba seeds on fructose-induced oxidative stress in RINm5f beta cells. The exposure of RINm5f beta cells to fructose triggered the loss of cell viability (-48%, < 0.001) and disruption of insulin secretion ( < 0.001) associated with of reactive oxygen species (ROS) production and a modulation of pro-oxidant and antioxidant signaling pathway. Cell pre-treatments with extracts considerably increased cell viability (+86% < 0.001) for simmondsin and +74% ( < 0.001) for aqueous extract and insulin secretion. The extracts also markedly decreased ROS (-69% ( < 0.001) for simmondsin and -59% ( < 0.001) for aqueous extract) and caspase-3 activation and improved antioxidant defense, inhibiting p22phox and increasing nuclear factor (erythroid-derived 2)-like 2 (Nrf2) levels (+70%, < 0.001) for aqueous extract. Simmondsin had no impact on Nrf2 levels. The richness and diversity of molecules present in jojoba seed extract makes jojoba a powerful agent to prevent the destruction of RINm5f beta cells induced by hyperglycemia.