Apoptosis in human beings
In humans, approximately 10-100 billion cells die daily, and the same amount of cells regenerate, all cells infected with microorganism or cancer cells are removed by NK lymphocytes.¨ Apoptosis is a death or "genetically programmed cellular". This process is necessarily for cells to work in their best state.¨ Apoptosis is divided into two branches: physiological cause and pathological cause. Cell death that occur physiologically are caused by apoptosis and are rapidly degenerated by macrophages. Caspasas are a large family of proteases that act in waterfalls. ¨A waterfall that leads to the activation of Caspase 3 Media apoptosis and is responsible for eliminating cells, recruiting macrophages and presenting a signal to conduct the elimination. When apoptotic cells are not efficiently absorbed by macrophages, they undergo secondary "secondary necrosis and release intracellular materials that represent a molecular pattern associated with damage"
Electronic light and microscopy have identified the various morphological changes that occur during apoptosis. During the initial apoptosis process, cell contraction and pyknosis are visible by light microscopy. "With cell contraction, cells are smaller in size, the cytoplasm is dense and the organelles are more compact". "Pirnosis is the result of chromatin condensation and this is the most characteristic feature of apoptosis" . In the histological examination with hematoxylin and eosin staining, apoptosis involves individual cells or small cell groups. The apoptotic cell appears as a round or oval mass with dark eosinophilic cytoplasm and dense fragments of purple nuclear chromatin¨. Electronic microscopy can better define subcellular changes. Early during the chromatin condensation phase, dense nuclear material in electrons is added characteristically peripherally under the nuclear membrane, although there may also be uniformly dense nuclei
Apoptosis also eliminates cells that are normal but are no longer necessary, such as those that produce antibodies once the need of the antibody has passed. Apoptosis can also be triggered in normal cells, otherwise, through external stimuli, which include the elimination of nutrients, toxins, hormones, heat and radiation.
Apoptosis is generally considered a cellular death mediated by Caspasa3. Apoptotic cells have different morphological characteristics, such as cell contraction, chromosomal condensation, ¨The nuclear fragmentation (late stage), bubble formation in the plasma membrane and the formation of apoptotic bodies, and exhibit biochemical changes, such as exposure ofphosphatidyl-l-series in the external plasma membrane¨ (early). Apoptosis can be activated through the apoptosis path. ¨ Apoptosis is triggered in many different ways, but all of them, ultimately, activate the enzymes known as caspases that alter DNA, organelles and cytoskeleton of a cell. Caspasas also recruit other cells to eat the remains of Moribundas cells¨ even after starting this suicidal process, cells can recover through a recently discovered process called Anastasis. But if "anástasis occurs late in apoptosis, surviving cells can have important chromosomal scars and other genetic defects that can lead to malignancy" "
¨CASPASA-8, CASPASA-9 and CASASA-3 are located in pivotal unions on the apoptotic pathways. Caspasa-8 starts disassembly in response to ligands that induce extracellular apoptosis and activates in a complex associated with the cytoplasmic death domains of receptors.¨ ¨ Caspasa-9 activates the desensamblage in response to agents or insults that trigger the release of cytochrome C from mitochondria and activate when they are complex with DATP, APAF-1 and extra-tramoscondrial cytochrome¨. Caspasa-3 seems to amplify the Caspasa-8 and Caspasa-9 indicates the full-fledged commitment of disassembly.¨ The first apoptosis signal, caspases are the factors that promote apoptosis, while BCL-2 inhibits apoptosis.¨
An important role of apoptosis is in the functioning of the immune system. Participate in the development of lymphocyte repertoires, which guarantees that cells that recognize themselves are destroyed before they can be activated, and it is also a path by which activated lymphocytes induce the destruction of infected cells.Lymphocytes can activate the apopptotic process in two ways. First, they secrete a protein range to the surface of the infected cell. One of these, "perforin, can be assembled to form transmembrane channels that allow other proteins to enter the cell" one of them is "the protease granzima B, which cuts and activates the specific procaspasses to start a waterfall.¨
¨The apopototic cell death inhibits oncogenesis in multiple stages, from transformation to metastasis¨ . Consequently, for cancer to develop and progress, apoptosis should be inhibited.¨ Cell death also plays an important role in the treatment of cancer, since it is the main effector function of many cancer therapies. ¨, a regulator of apoptosis, also controls metabolism by limiting glycolysis and facilitating mitochondrial breathing. Consequently, with deregulated metabolism and the inactivation of cancer cells are well equipped to disable apoptotic machinery. ¨ Induces apoptosis in cells not mainly transformed by direct transcriptional activation of BH3 pro-apototic proteins only Puma¨ ¨ Flavonoids have gained importance as anti-cancer agents and have demonstrated great potential as anti-gagy cytotoxic agents "that promote apoptosis in cancer cells.
¨The proteins only bh3 are regulated up in response to apopaptotic stress. Bax and Bak activate that oligomerize and result in the permeabilization of the mitochondrial membrane. Cytochrome C, SMAC and IMO are released and apoptosome is formed from Procaspase-9, Datp, Citocroma C and APAF-1. ¨ . ¨ Small molecules that are directed directly to the antiapopptotic proteins of the BCL-2 family have entered the cancer test clinic. ¨ . ¨ Antiapopototic proteins include BCL-2, BCL-XL and MCL-1, which have BH1-4 domains. The members of the BCL-2 pro-apuptotic family are divided into two subclasses, which comprise the BH3¨
Apoptosis represents spontaneous cell death and requires energy, with specific morphological and biochemical characteristics. A sequence of events results in the elimination of damaged cells. Proliferative conditions, physiological remodeling and neoplastic lesions favor apoptosis. Diseases such as cancer, Parkinson, Alzheimer. The apoptosis process is developed by phases.
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