Peroxisomes are membranous organelles found in cells. They are differentiated in many ways, including their enzymes, oxidases and catalases in the form of vesicles that are responsible for detoxification.
The main function of peroxisomes is to participate in lipidic metabolism, mainly in the shortening of long chain fatty acids, so that their oxidation can be complete in the mitochondria, in addition to oxidizing amino acids, and other substrates.
Toxic products, such as hydrogen peroxide generated in some reactions degrade within the peroxisome rapidly, due to the oxidative enzyme that is used as an intermediate in some substances. The ethanol we drink is oxidized by the action of catalase, almost 50%.
Among other functions of the peroxisomes, this one of taking charge of unchaining oxidative reactions that allows to produce heat.
The formation of peroxisomes takes place in the endoplasmic reticulum, and they have the ability to divide, which generally occurs during cell division.
There are 2 types of peroxisome disorders:
-Those with defective formation of peroxisomes
-Defects in peroxisome enzymes
X-linked adrenoleukodystrophy is the most common peroxisome disorder (incidence of 1/17,000 births), all others are autosomal recessive, with a combined incidence of about 1/50,000 births.
They are attributed a critical role in aging and loss of cell cycle control that can lead to tumors and cancer.
The proteins involved in peroxisome biogenesis and in the transport of peroxisome proteins are called peroxins and are encoded by the PEX genes. So far, 15 PEX genes are known.
More than 25 diseases are known to be related to the dysfunction of the enzymatic activities of peroxisomes, known as peroxisome genesis abnormalities (PBD).
Peroxisome proliferator activated receptors (PPARs) are important in the development of obesity and insulin resistance.
Peroxisome proliferator activated receptors (PPARs) are a family of nuclear transcription factors that belong to the steroid receptor superfamily.
PPARs control gene expression of fatty acid synthesis and oxidation, and are involved in fatty acid storage in different tissues.
PPARs are located in most tissues, being PPARalpha (where phenofibrates act) the most abundant form in liver and skeletal muscle, while PPARgamma is located mainly in adipose tissue.
There must be a balance between the different isoforms of PPARs, especially PPARbeta and PPARgamma (where some antidiabetic such as thiazolidinediones and certain anti-inflammatory drugs act), to maintain a balance between fatty acid synthesis and oxidation, since an imbalance in the balance is associated with the development of obesity and insulin resistance.
The study of PPAR has allowed progress in the knowledge of the molecular bases of such common metabolic disorders as obesity and type 2 diabetes.
The expression of PPAR in various organs oscillates daily, and studies have shown that intestinal microbiota can influence the activities of PPAR in various metabolic organs.
-Int J Mol Sci. 2019 Jan 17;20(2):387. doi: 10.3390/ijms20020387.
Interactions between Host PPARs and Gut Microbiota in Health and Disease. Arif Ul Hasan, Asadur Rahman, Hiroyuki Kobori.
-Schluter, A., Real-Chicharro, A., Gabaldon, T., Sanchez-Jimenez, F. and Pujol, A. (2010) PeroxisomeDB 2.0: an integrative view of the global peroxisomal metabolome. Nucleic Acids Res, 38, D800-5.
Peroxisomes and their function, Peroxisomes and disease, Peroxisomes and diabetes mellitus, Peroxisomes and fatty liver, Peroxisomes and PPARs, PPARs and microbiota, PPARs and insulin resistance, Peroxisomes and aging, defective peroxisome formation, defects in peroxisome enzymes, lipid metabolism, and peroxisomes