Carnosol attenuates high glucose damage in human retinal endothelial cells through regulation of ERK/Nrf2/HO-1 pathway

Abstract

Carnosol is a natural compound with antioxidant properties. Based on this evidence, in the present study we investigated whether this compound can protect retinal vascular endothelium from hyperglycemic insult responsible for diabetic retinopathy development. We performed in vitro study on human retinal endothelial cells (HREC) cultured both in normal and high glucose conditions to assess the effects of carnosol on cell viability, Nrf2 expression, HO-1 activity, and ERK1/2 expression. HREC exposed to high glucose insult were treated with carnosol. Data indicated that carnosol treatment is able to induce HO-1 expression via Nrf2 activation and counteracts the damage elicited by high glucose. Further, carnosol activation of Nrf2/HO-1 signaling axis involves ERK1/2 pathway. These data confirm the therapeutic value of carnosol by suggesting its use to treat diabetic retinopathy.

Graphical Abstract

Keywords:

• Diabetic retinopathy
• carnosol
• human retinal endothelial cells (HREC)
• heme oxygenase-1 (HO-1)
• apoptosis

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was funded by Italian Ministry of Education, University and Research (MIUR) [grant number PRIN 2017TSHBXZ_003] and by the Grant PIano inCEntivi RIcerca (PIACERI) Ateneo 2020/2022 – Linea Intervento 2.