AktPKB

**AktPKB (AKT/PKB Pathway)**

The Akt/PKB (Protein Kinase B) pathway is a central signaling cascade involved in various cellular processes, including metabolism, survival, proliferation, and growth. Akt, also known as Protein Kinase B, is a serine/threonine kinase that plays a pivotal role in transmitting signals from growth factors and cytokines to the nucleus. It is activated through phosphorylation by two upstream kinases: PDK1 (3-Phosphoinositide Dependent Protein Kinase-1) and mTORC2 (Mechanistic Target of Rapamycin Complex 2).

Upon activation, Akt phosphorylates and inhibits several pro-apoptotic proteins, such as Bad, Caspase-9, and FOXO transcription factors, thereby promoting cell survival. Additionally, Akt stimulates glucose uptake by phosphorylating and activating GLUT4 (Glucose Transporter Type 4) in muscle and adipose tissues, contributing to metabolic regulation. It also promotes lipogenesis by activating SREBP-1 (Sterol Regulatory Element-Binding Protein 1) and inhibits lipolysis.

Mutations or dysregulation in the Akt pathway are associated with various diseases, including cancer, diabetes, and neurodegenerative disorders. For instance, overactivation of Akt is often observed in tumors, where it contributes to uncontrolled cell growth and resistance to apoptosis. Conversely, reduced Akt activity can lead to metabolic disorders and impaired cellular responses to growth signals.

The Akt pathway is tightly regulated to maintain cellular homeostasis. Negative feedback loops, protein-protein interactions, and post-translational modifications ensure precise control over its activity. Understanding the intricacies of the Akt/PKB pathway provides valuable insights into potential therapeutic targets for treating diseases characterized by aberrant signaling.