Novel ABCA1 peptide agonists with antidiabetic action

Area of Science:

• Biochemistry
• Metabolic Diseases
• Pharmacology

Background:

• Apolipoprotein E (apoE)-derived peptides targeting ATP-binding cassette transporter A1 (ABCA1) have demonstrated anti-atherosclerotic and potential anti-diabetic effects.
• A second generation of ABCA1 agonists, CS6253 and T6991-2, were developed to further investigate their impact on metabolic health.

Purpose of the Study:

• To evaluate the in vitro and in vivo effects of novel ABCA1 peptide agonists, CS6253 and T6991-2, on glucose homeostasis.
• To determine the mechanisms by which these peptides influence glucose metabolism and insulin secretion.

Main Methods:

• In vivo studies using a prediabetic diet-induced obesity mouse model and leptin-deficient (ob/ob) mice to assess glucose tolerance.
• In vitro studies using pancreatic INS-1 β-cells and hepatic cells to investigate insulin secretion, gluconeogenesis, and glucose transport.
• Utilized siRNA to render INS-1 β-cells deficient in leptin receptors for specific mechanistic studies.

Main Results:

• Both CS6253 and T6991-2 significantly improved glucose tolerance in a prediabetic mouse model, primarily by enhancing insulin secretion.
• T6991-2 demonstrated efficacy in improving glucose tolerance in leptin-deficient (ob/ob) mice.
• CS6253 enhanced insulin secretion in pancreatic β-cells, even under conditions of leptin receptor deficiency.
• In vitro studies indicated that CS6253 reduces hepatic gluconeogenesis and glucose transport while promoting insulin-stimulated glucose uptake and utilization.

Conclusions:

• The novel ABCA1 peptide agonists CS6253 and T6991-2 exhibit significant anti-diabetic properties by improving glucose tolerance and enhancing insulin secretion.
• CS6253 also demonstrates beneficial effects on hepatic glucose metabolism and insulin sensitivity.
• These findings highlight the potential of CS6253 and T6991-2 as therapeutic agents for managing type 2 diabetes, offering additional benefits beyond their previously established anti-atherosclerotic effects.