Sulforaphane improves disrupted ER-mitochondria interactions and suppresses exaggerated hepatic glucose production

• Aims: Exaggerated hepatic glucose production is one of the hallmarks of type 2 diabetes. Sulforaphane (SFN) has been suggested as a new potential anti-diabetic compound. However, the effects of SFN in hepatocytes are yet unclear. Accumulating evidence points to the close structural contacts between the ER and mitochondria, known as mitochondria-associated ER membranes (MAMs), as important hubs for hepatic metabolism. We wanted to investigate whether SFN could affect hepatic glucose production and MAMs. Materials and methods: We used proximity ligation assays, analysis of ER stress markers and glucose production assays in hepatoma cell lines, primary mouse hepatocytes and diabetic animal models. Results: SFN counteracted the increase of glucose production in palmitate-treated mouse hepatocytes. SFN also counteracted palmitate-induced MAM disruptions. Moreover, SFN decreased the ER stress markers CHOP and Grp78. In ob/ob mice, SFN improved glucose tolerance and reduced exaggerated glucose production. In livers of these mice, SFN increased MAM protein content, restored impaired VDAC1-IP3R1 interactions and reduced ER stress markers. In mice on HFHSD, SFN improved glucose tolerance, MAM protein content and ER-mitochondria interactions to a similar extent to that of metformin. Conclusions: The present findings show that MAMs are severely reduced in animal models of glucose intolerance, which reinforces the role of MAMs as a hub for insulin signaling in the liver. We also show that SFN restores MAMs and improves glucose tolerance by a similar magnitude to that of metformin. These data highlight SFN as a new potential anti-diabetic compound. (C) 2017 Elsevier B.V. All rights reserved.

Ämnesord

MEDICIN OCH HÄLSOVETENSKAP  -- Klinisk medicin -- Endokrinologi och diabetes (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Clinical Medicine -- Endocrinology and Diabetes (hsv//eng)

Nyckelord

Mitochondria-associated ER membranes

Type 2 diabetes

Sulphoraphane

endoplasmic-reticulum stress

induced insulin-resistance

type-2

diabetes-mellitus

high-fat diet

oxidative stress

dysfunction

nrf2

disease

cells

lipogenesis

Cell Biology

Endocrinology & Metabolism

fronzo ra

1989

metabolism-clinical and experimental

v38

p387

Publikations- och innehållstyp

ref (ämneskategori)

art (ämneskategori)