Protein Tyrosine Phosphatase 1B Deficiency Improves Glucose Homeostasis in Type 1 Diabetes Treated With Leptin

Area of Science:

• Endocrinology
• Metabolic Diseases
• Pharmacology

Background:

• Leptin, an adipocyte-secreted hormone, has therapeutic potential for type 1 diabetes (T1D).
• Protein tyrosine phosphatase 1B (PTP1B) negatively regulates leptin receptor signaling, impacting metabolic control.

Purpose of the Study:

• To investigate the role of PTP1B in T1D treatment using PTP1B-deficient mice and a PTP1B inhibitor.
• To evaluate the combined therapeutic effects of leptin and PTP1B inhibition in a T1D mouse model.

Main Methods:

• Utilized streptozotocin-induced T1D wild-type (WT) and PTP1B-deficient (KO) mice.
• Administered leptin peripherally or centrally, and a PTP1B inhibitor.
• Assessed glucose metabolism, hepatic gluconeogenesis, and glucose uptake in adipose tissue and muscle.

Main Results:

• PTP1B KO mice exhibited significantly improved glucose metabolism compared to T1D WT mice.
• Leptin alone partially improved glucose metabolism in T1D WT mice.
• Combined peripheral therapy with leptin and a PTP1B inhibitor normalized glucose metabolism in T1D WT mice.
• Leptin's effects on suppressing gluconeogenesis and enhancing glucose uptake were amplified by PTP1B deficiency.

Conclusions:

• PTP1B deficiency or inhibition enhances leptin's efficacy in improving glucose metabolism in T1D.
• Targeting PTP1B alongside leptin presents a potential alternative therapeutic strategy for managing type 1 diabetes.