Squamosamide Derivative FLZ Protects Pancreatic β-Cells from Glucotoxicity by Stimulating Akt-FOXO1 Pathway

Area of Science:

• Endocrinology
• Cell Biology
• Pharmacology

Background:

• Chronic hyperglycemia impairs pancreatic beta-cell function.
• This leads to increased apoptosis and reduced insulin secretion.
• Effective protective agents against glucotoxicity are currently lacking.

Purpose of the Study:

• To investigate the potential antiglucotoxic effects of FLZ, a synthetic squamosamide derivative.
• To evaluate FLZ's impact on beta-cell viability, apoptosis, and insulin secretion under high glucose conditions.
• To elucidate the molecular mechanisms underlying FLZ's protective action.

Main Methods:

• INS-1E cells and mouse islets were cultured under high glucose (30 mM) conditions.
• FLZ was administered in a dose-dependent manner.
• Cell viability, apoptosis, protein expression (FOXO1, PDX-1), Akt phosphorylation, and ATP/ADP ratio were assessed.

Main Results:

• FLZ reversed high glucose-induced reduction in beta-cell viability and insulin secretion.
• FLZ dose-dependently reduced apoptosis by decreasing nuclear FOXO1 localization.
• FLZ enhanced PDX-1 expression and nuclear localization via Akt activation, which was essential for its protective effects.

Conclusions:

• FLZ demonstrates significant antiglucotoxicity in pancreatic beta cells.
• FLZ protects against hyperglycemia-induced beta-cell failure by modulating FOXO1 and Akt/PDX-1 pathways.
• FLZ represents a promising therapeutic candidate for managing hyperglycemia-related complications.