What is Enterocyte apoptosis?
Apoptosis is a highly regulated type of programmed cell death that allows for the homeostatic turnover of the epithelial layer. Recent studies have suggested that microbial modulation of enterocyte apoptosis can result in increased epithelial permeability, leading to gastrointestinal pathophysiology.
Where does apoptosis occur in the villus?
Two sites of epithelial cell death have been described along the length of the villus: the first takes place in the crypt at the level of the stem and early transit cells and is sometimes referred to as “spontaneous” apoptosis and the second at the villus tip or to the surface epithelial cuff in the colon, where …
What are the 2 pathways that initiate apoptosis?
The two main pathways of apoptosis are extrinsic and intrinsic as well as a perforin/granzyme pathway. Each requires specific triggering signals to begin an energy-dependent cascade of molecular events.
What are the pathways of apoptosis?
There are two major pathways leading to apoptosis in the mammalian system: an extrinsic pathway initiated by death receptors and an intrinsic pathway that occurs through the mitochondria (Figure 1). The extrinsic pathway depends on binding of appropriate exogenous mediators to death receptors at the cell surface.
What is the intestinal epithelium?
The intestinal epithelium is the single cell layer that form the luminal surface (lining) of both the small and large intestine (colon) of the gastrointestinal tract.
What is intestinal cell?
The intestinal epithelium is a single layer of cells organized into crypts and villi, known as the most rapidly self-renewing tissue in adult mammals. The cells that line the intestinal lumen perform the primary functions of digestion, water and nutrient absorption, and forms a barrier against luminal pathogens.
What is apoptosis what is its purpose?
Cell biologist Michael Overholtzer explains apoptosis, a form of programmed cell death that can lead to cancer when it doesn’t function properly. It also plays an important role in cancer.” One purpose of apoptosis is to eliminate cells that contain potentially dangerous mutations.
Do intestinal cells undergo apoptosis?
Apoptosis is especially relevant in the gastrointestinal tract, as the mammalian intestinal mucosa undergoes a process of continual cell turnover that is essential for maintenance of normal function.
What can trigger intrinsic apoptosis?
Intrinsic pathway of apoptosis The intrinsic apoptosis pathway begins when an injury occurs within the cell. Intrinsic stresses such as oncogenes, direct DNA damage, hypoxia, and survival factor deprivation, can activate the intrinsic apoptotic pathway.
How does TrkB-plc / IP3 affect enterocyte apoptosis in mice?
In conclusion, inhibition of TrkB-PLC/IP3 pathway can increase the expression of intestinal inflammatory factors and promote enterocyte apoptosis in mice with colitis. Ulcerative colitis is a kind of chronic colitis with repeated attack and unknown etiology [ 1, 2 ]. Recently, its incidence rate in human beings has increased year by year in China.
How does NAC prevent intestinal lymphocyte apoptosis?
Recently, it has been proved that NAC prevents exercise-induced intestinal lymphocyte apoptosis by maintaining intracellular GSH contents and reducing mitochondrial membrane depolarisation (14). Administration of NAC before ischaemia in experiments was effective in the prevention of bacterial translocation and oxidative stress (16).
Which is part of the TrkB-plc / IP3 pathway?
The TrkB-PLC/IP3 pathway is mainly composed of protein-tyrosine kinase receptor B (TrkB), phospholipase C (PLC), and inositol triphosphate (IP3).