Bee stings and venomous snake bites cause immediate inflammation, resulting in pain and swelling. The enzyme in venom that triggers this immune response is phospholipase A2. This enzyme is also present in human tissue. However, this killing mechanism comes at a cost to the human host.
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Bee stings and venomous snake bites cause immediate inflammation, resulting in pain and swelling. The enzyme in venom that triggers this immune response is phospholipase A2. This enzyme is also present in human tissue. However, this killing mechanism comes at a cost to the human host. Lysolecithin products are involved in the pain response and cause hemolysis of erythrocytes. The most common free fatty acid produced by PLA2 is arachidonic acid, which can increase the production of powerful mediators of inflammation: prostaglandins, leukotrienes, and thromboxanes, collectively called eicosanoids.
Release of these mediators initiates the pain, swelling, and other unpleasant symptoms we experience as part of an inflammatory response. Microorganisms such as Candida albicans and certain Clostridia species produce PLA2, which increases the ability of the microorganism to infect the host.
This same enzyme is produced in the body as a response to invading microorganisms and foreign proteins such as allergens, particularly house dust and cats. Physical trauma may also cause significant increases in PLA2, contributing to tissue damage and brain injury.
They have strong antibacterial and antiviral properties as part of the innate immune system, but also participate in many other biochemical processes that include cell signaling, cell proliferation and differentiation, cell migration and apoptosis, and modulation of inflammatory response. Multiple sclerosis involves both antigen-specific mechanisms and components of the innate immune system that result in inflammatory response.
Inflammation is the hallmark of rheumatoid arthritis RA , a joint-destructive autoimmune disease. In cancer, the spread of tumor cells from a primary tumor to the secondary sites within the body is a complicated process involving cell proliferation and migration, degradation of basement membranes, invasion, adhesion, and angiogenesis. Glucocorticoids such as the natural hormone cortisol and pharmaceutical agents such as dexamethasone inhibit the production of phospholipase, decreasing harm caused by the enzyme but also decreasing the benefits of the enzyme in killing harmful microorganisms.
Vitamin E is also an inhibitor of PLA2. No side effects were noticed at the lower doses of CDP-choline and only some mild gastrointestinal symptoms were found using higher doses. No abnormal blood chemistry or hematology values were found after the use of CDP-choline.
There are no dietary restrictions. This test is convenient to include with the organic acids test. Since chelating agents might interfere with the test, they should not be used for at least 48 hours prior to testing.
These enzymes are responsible for fast turnover rates of cellular phospholipids. Most notably, it can be found in mammalian cells such as plasma of rat livers and bovine brains, and can also be found in metazoan parasites, protozoan parasites, and snake venom. Substrate specificity[ edit ] PLA1 hydrolyzes nonionic substrates preferentially over ionic substrates. Optimum pH conditions for PLA1 activity on neutral phospholipids is around 7. The serine is considered the active site in the enzyme. The cysteine residues are responsible for key structural motifs such as the lid domain and the B9 domain, both of which are lipid binding surface loops. These two loops can vary between each PLA1.
Phospholipase A2 Activity Test