Membrane peroxidases

Abstract

It is well known that the partial reduction of oxygen can result in the formation of highly reactive oxygen products. Hydrogen peroxide is one of these metabolites of oxygen. Peroxidases utilize this metabolite for a variety of functions. It is the purpose of this treatise to review the nature and function of various membrane peroxidases in the body.

Light‐emitting diode therapy in exercise‐trained mice increases muscle performance, cytochrome c oxidase activity, ATP and cell proliferation

“…In this context, the effect of LEDT to protect against exercise-muscle damage has suggested a modulation of ROS [27,28] produced naturally during exercise [18,20] and for this reason we investigated several oxidative stress markers in the current study: protein carbonyls, glutathione (total and oxidized), catalase, lipid peroxidation using TBARS (contents of malondialdehyde -MDA) and protein thiols. Protein carbonyl content was significantly decreased only in LEDT-After group, promoting an effective protection against protein oxidation and injury as well as suggesting better protein function [20][21][22]. Protein carbonyls were investigated in the current study because they are formed quickly after a bout of oxidative stress and are stable for hours or days, being a specific and reliable oxidative stress marker [22].…”

“…Protein carbonyl content was significantly decreased only in LEDT-After group, promoting an effective protection against protein oxidation and injury as well as suggesting better protein function [20][21][22]. Protein carbonyls were investigated in the current study because they are formed quickly after a bout of oxidative stress and are stable for hours or days, being a specific and reliable oxidative stress marker [22]. To our knowledge this is the first study measuring protein carbonyls as a marker of oxidative stress of muscles exposed to LEDT.…”

“…Several biological factors govern success or optimum performance in sports that involve high-intensity exercise, or alternatively involve endurance exercise, that both require muscle adaptation during pre-competition training programs. Among these factors are the depletion of the energy supply for muscle contraction which comprises adenosine triphosphate (ATP) and glycogen; accumulation of possibly deleterious metabolites from energy metabolism such as lactate, adenosine diphosphate (ADP), adenosine monophosphate (AMP), ions Ca 2+ and H + ; production of reactive oxygen species (ROS) [19][20][21][22]; and the recovery process from microlesions or muscle damage [23]. Light therapy seems to be able to benefit all these "limitations" since its mechanism of action involves the improvement of mitochondrial metabolism and increased ATP synthesis [24,25] owing to increased activity of cytochrome c oxidase (COX) in the electron transport chain (ETC) [9,25,26]; reduction of reactive oxygen species (ROS) or improvement of oxidative stress defense [27,28]; and can stimulate faster muscle repair due to an increased proliferation and differentiation of muscle cells [29].…”

“…Confirming previous hypotheses regarding oxidative stress balance, the content of total glutathione (GSH) was significantly moved towards oxidized (GSSH) in LEDT-Before animals compared to animals in LEDT-Sham; LEDT-Before-After animals compared to LEDT-Sham and LEDT-Before as well as in LEDT-After animals compared to LEDT-Sham and LEDT-Before. These results may have occurred due to the increased activity or up-regulation of glutathione peroxidase (GPX) enzyme activity [18] responsible for oxidizing GSH to GSSH during the process of reduction of hydrogen peroxide (H 2 O 2 ) to water [20][21][22]. Moreover, the muscular GSH content was significantly higher in Control group animals compared to LEDT-Sham and LEDT-Before, but without statistical significance compared to both groups treated with LEDT after each training session.…”

Scaffold/matrix attachment regions from CHO cell chromosome enhanced the stable transfection efficiency and the expression of transgene in CHO cells

“…The most consistent features of S/MARs include an overall high AT-rich and origin of replication site (ATTA, ATTTA, and ATTTTA), which may form the base for unsparing regions for the initiation of replication [11], the binding sites of DNA topoisomerase II, SATB1 motif, kinked DNA, and curved DNA, etc. MARFinder and MARScan have been used previously to identify functional S/MARs elements in Entamoeba and human genome [12,13]. MARFinder, known as MAR-Wiz (http://genomecluster.secs.oakland.edu/marwiz/) is based on the statistical occurrence of motifs related to DNA secondary structure.…”