Apoptosis is a physiological response in development and homeostasis of metazoans. Apoptosis is triggered during pathological events as a means to renew affected tissues and eliminate cancer cells. The immune system regulates the extrinsic pathway of apoptosis, where signals such as TNFα or displayed ligands on the surface of immune cells trigger signal cascades by death receptors present on targeted cells.

N4-acetylcytidine (N4A) is an organic compound and a metabolite of transferrable ribonucleic acid. Its molecular formula is C11H15N3O6. Earlier studies suggest that N4A was mainly found on tRNA and 18S rRNA, while recent studies have shown that there is also a large amount of N4A on mRNA, whose abundance is not even lower than the m7G cap modification carried by mRNA.

The important immune cells in the brain are called microglia acting as the central junction between neuroinflammation and neurodegenerative diseases. In patients of cognitive disorders and Alzheimer’s disease (AD) animal models, amoebic morphology and inflammatory pathways are activated to release numerous cells in the inflammatory factors by active microglia.

Macrophages are innate immune cells that play a key role in regulation of innate and adaptive immune responses against infections with several pathogens as they respond to pathogens and tissue injury, serve as antigen presenting cells priming the adaptive immune response, drive inflammation and host defense as well as repairing

Mammals have two main types of adipose tissue (commonly defined as “fat”): the white adipose tissue (WAT), which represents the main energy reservoir of the body and provides lipids as substrates for other tissues, and the brown adipose tissue (BAT), which uses lipids for heat production (a process called “thermogenesis”).