Sorcin counteracts lipotoxicity in palmitate-exposed human beta-cells

• In obese subjects elevated circulating levels of free fatty acids (FFAs) have been connected with hyperinsulinemia and development of type 2 diabetes. In human islets insulin secretion is accentuated when palmitate concentration is increased for short time periods. Our previous findings indicated that increased sorcin expression may delay development of ER stress in such human islets exposed to palmitate. In the present study we tested this hypothesis by using human islets and human EndoC-βH1 cells transfected with lenti-viral transduction particles of anti-sorcin. Human islets and EndoC-βH1 cells treated with palmitate for 2 days induced sorcin expression. The beta-cells showed enhanced glucose-stimulated insulin secretion (GSIS), mitochondrial respiration and glycolysis and no alterations in ER stress and apoptosis. When sorcin was knocked down, palmitate-induced upregulation of sorcin was reduced. The beta-cells showed reduced GSIS, mitochondrial respiration and glycolysis and increased ER stress and apoptosis. We conclude that enhanced sorcin levels play a role in preventing lipotoxicity in beta-cells exposed to elevated palmitate levels for prolonged time periods.

Ämnesord

MEDICIN OCH HÄLSOVETENSKAP  -- Medicinska och farmaceutiska grundvetenskaper -- Cell- och molekylärbiologi (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Basic Medicine -- Cell and Molecular Biology (hsv//eng)

Nyckelord

Sorcin

palmitate

human islets

EndoC-βH1 cells

insulin secretion

mitochondrial respiration

ER stress

Medical Cell Biology

Medicinsk cellbiologi

Publikations- och innehållstyp

vet (ämneskategori)

ovr (ämneskategori)