Protein Kinases in Obesity, and the Kinase-Targeted Therapy

Area of Science:

• Biochemistry
• Cellular Biology
• Metabolic Disorders

Background:

• Protein kinases and phosphatases are crucial for physiological processes, exhibiting substrate specificity and regulatory mechanisms.
• Dual-specificity phosphatases are key signal transduction enzymes involved in cellular processes and obesity, often impairing insulin signaling through pathways like JNK.
• Obesity is linked to impaired glucose metabolism, insulin resistance, oxidative stress, and endoplasmic reticulum (ER) stress, involving kinases such as AMPK, mTOR, and PKC.

Purpose of the Study:

• To explore the role of protein kinases and phosphatases in obesity and related metabolic dysfunctions.
• To investigate the mechanisms by which these enzymes influence insulin signaling, lipotoxicity, and oxidative stress in obesity.
• To evaluate the potential of pharmacological interventions targeting these pathways for managing obesity and its complications.

Main Methods:

• Review of literature on protein kinase and phosphatase signaling in obesity.
• Analysis of the involvement of specific kinases (JNK, AMPK, mTOR, PKC) and phosphatases in insulin resistance and metabolic regulation.
• Examination of the effects of pharmacological agents (nifedipine, metformin, liraglutide, berberine, rapamycin) on obesity-related pathways.

Main Results:

• Impaired insulin signaling in obesity is associated with activated inhibitor of kappa B-kinase beta and JNK, which are activated by oxidative and ER stress.
• Obesity-activated kinases like CaMKII/p38 suppress insulin signaling by activating ATF-4 via ER stress.
• Pharmacological agents like metformin and liraglutide demonstrate potential in alleviating lipotoxicity and insulin resistance by modulating AMPK, mTOR, and oxidative stress pathways.

Conclusions:

• Protein kinases and phosphatases are central to metabolic regulation and dysfunction in obesity.
• Targeting specific signaling pathways, such as those involving AMPK, mTOR, and stress responses, offers therapeutic potential for obesity and associated insulin resistance.
• Pharmacological interventions like metformin and liraglutide show promise in mitigating obesity-induced metabolic damage and improving insulin sensitivity.