scholarly journals Deoxygenation Affects Composition of Membrane-Bound Proteins in Human Erythrocytes

2016 ◽  
Vol 39 (1) ◽  
pp. 81-88 ◽  
Author(s):  
Oksana G. Luneva ◽  
Svetlana V. Sidorenko ◽  
Olga O. Ponomarchuk ◽  
Artem M. Tverskoy ◽  
Aleksander A. Cherkashin ◽  
...  

Background/Aims: ATP release from erythrocyte plays a key role in hypoxia-induced elevation of blood flow in systematic circulation. We have previously shown that hemolysis contributes to erythrocyte ATP release triggered by several stimuli, including hypoxia, but the molecular mechanisms of hypoxia-increased membrane fragility remain unknown. Methods: In this study, we compared the action of hypoxia on hemolysis, ATP release and the composition of membrane-bound proteins in human erythrocytes. Results: Twenty minutes incubation of human erythrocytes in the oxygen-free environment increased the content of extracellular hemoglobin by ∼1.5 fold. Paired measurements of hemoglobin and ATP content in the same samples, showed a positive correlation between hemolysis and ATP release. Comparative analysis of SDS-PAGE electrophoresis of erythrocyte ghosts obtained under control and deoxygenated conditions revealed a ∼2-fold elevation of the content of membrane-bound protein with Mr of ∼60 kDa. Conclusion: Deoxygenation of human erythrocytes affects composition of membrane-bound proteins. Additional experiments should be performed to identify the molecular origin of 60 kDa protein and its role in the attenuation of erythrocyte integrity and ATP release in hypoxic conditions.

2009 ◽  
Vol 87 (6) ◽  
pp. 419-425 ◽  
Author(s):  
Daniel Prins ◽  
Marek Michalak

An understanding of cardiac pathologies and the molecular mechanisms thereof is essential for the development of therapies for cardiovascular disease, a common cause of death in Western societies. Investigations into heart diseases have shown that the endoplasmic reticulum and its diverse functions may lie at the center of many cardiac pathologies. Animal models have demonstrated that in numerous cases, faulty endoplasmic reticulum activity is manifested in defective cardiogenesis or impaired heart function. These findings suggest that the endoplasmic and sarcoplasmic reticulum membranes may represent functionally independent organelles responsible for specialized functions in the heart. This review addresses the molecular pathways linking endoplasmic reticulum function and malfunction with impaired cardiac phenotypes. The endoplasmic reticulum affects cardiac development and function through Ca2+-dependent pathways, its catalytic role in the proper folding and targeting of membrane-bound and secretory proteins, and its response to cellular stress events, particularly hypoxic conditions. These pathways present potential novel targets for treatment of cardiac disease.


Author(s):  
Debanjan Kundu ◽  
Vikash Kumar Dubey

Abstract:: Various neurodegenerative disorders have molecular origin but some common molecular mechanisms. In the current scenario, there are very few treatment regimens present for advanced neurodegenerative diseases. In this context, there is an urgent need for alternate options in the form of natural compounds with an ameliorating effect on patients. There have been individual scattered experiments trying to identify potential values of various intracellular metabolites. Purines and Pyrimidines, which are vital molecules governing various aspects of cellular biochemical reactions, have been long sought as crucial candidates for the same, but there are still many questions that go unanswered. Some critical functions of these molecules associated with neuromodulation activities have been identified. They are also known to play a role in foetal neurodevelopment, but there is a lacuna in understanding their mechanisms. In this review, we have tried to assemble and identify the importance of purines and pyrimidines, connecting them with the prevalence of neurodegenerative diseases. The leading cause of this class of diseases is protein misfolding and the formation of amyloids. A direct correlation between loss of balance in cellular homeostasis and amyloidosis is yet an unexplored area. This review aims at bringing the current literature available under one umbrella serving as a foundation for further extensive research in this field of drug development in neurodegenerative diseases.


2014 ◽  
Vol 81 (3) ◽  
pp. 1024-1031 ◽  
Author(s):  
Bhagyalakshmi Kalidass ◽  
Muhammad Farhan Ul-Haque ◽  
Bipin S. Baral ◽  
Alan A. DiSpirito ◽  
Jeremy D. Semrau

ABSTRACTIt is well known that copper is a key factor regulating expression of the two forms of methane monooxygenase found in proteobacterial methanotrophs. Of these forms, the cytoplasmic, or soluble, methane monooxygenase (sMMO) is expressed only at low copper concentrations. The membrane-bound, or particulate, methane monooxygenase (pMMO) is constitutively expressed with respect to copper, and such expression increases with increasing copper. Recent findings have shown that copper uptake is mediated by a modified polypeptide, or chalkophore, termed methanobactin. Although methanobactin has high specificity for copper, it can bind other metals, e.g., gold. Here we show that inMethylosinus trichosporiumOB3b, sMMO is expressed and active in the presence of copper if gold is also simultaneously present. Such expression appears to be due to gold binding to methanobactin produced byM. trichosporiumOB3b, thereby limiting copper uptake. Such expression and activity, however, was significantly reduced if methanobactin preloaded with copper was also added. Further, quantitative reverse transcriptase PCR (RT-qPCR) of transcripts of genes encoding polypeptides of both forms of MMO and SDS-PAGE results indicate that both sMMO and pMMO can be expressed when copper and gold are present, as gold effectively competes with copper for binding to methanobactin. Such findings suggest that under certain geochemical conditions, both forms of MMO may be expressed and activein situ. Finally, these findings also suggest strategies whereby field sites can be manipulated to enhance sMMO expression, i.e., through the addition of a metal that can compete with copper for binding to methanobactin.


2014 ◽  
Vol 66 (3) ◽  
pp. 665-671 ◽  
Author(s):  
A.F.S. Nogueira ◽  
P.A. Di Filippo ◽  
L.A. Anai ◽  
M.C. Vieira ◽  
K.M.M.G. Simplício ◽  
...  

The initial inflammatory stages of the colic syndrome include changes known as acute phase response. The aim of this study was to contribute with the establishment of reference values concerning the electrophoretogram of peritoneal liquid from healthy horses and horses submitted to experimentally induced intestinal obstruction. Twenty-one horses were allotted in four groups: duodenal obstruction (DG), ileum obstruction (IG), left-dorsal colon obstruction (MG), and control group (CG). Peritoneal liquid was sampled before obtruction (T0), with 3 hours of obstruction (T3) and 6, 30, 102 and 174 hours after desobstructing (T6, T30, T102 and T174, respectively). Total protein levels were determined by the biuret method and protein fractions were obtained by SDS-PAGE electrophoresis. The acute phase proteins (APP) identified were Immunoglobulin-A, ceruloplasmin, transferrin, albumin, α1-antitrypsin, heavy and light chains of immunoglobulin-G, haptoglobin, α1-acid glycoprotein and a still unnamed protein, which was called P24. There was no difference (P>0.3) in protein levels among groups, although a significant difference (P>0.05) was observed between distinct experimental moments in each group evidencing a higher response of the APP in the obstructed groups. The APP fractioning of the peritoneal liquid was standardized to establish a standard curve for healthy equines and those submitted to induced intestinal obstruction. Moreover, it was verified that the SDS-PAGE electrophoresis was sensitive and effective to help diagnose abdominal inflammatory processes.


2006 ◽  
Vol 84 (1) ◽  
pp. 49-59 ◽  
Author(s):  
Aaron Y. Lai ◽  
Kathryn G. Todd

The precise role of microglia in stroke and cerebral ischemia has been the subject of debate for a number of years. Microglia are capable of synthesizing numerous soluble and membrane-bound biomolecules, some known to be neuroprotective, some neurotoxic, whereas others have less definitive bioactivities. The molecular mechanisms through which microglia activate these molecules have thus become an important area of ischemia research. Here we provide a survey review that summarizes the key actions of microglial factors in cerebral ischemia including complement proteins, chemokines, pro-inflammatory cytokines, neurotrophic factors, hormones, and proteinases, as well several important messenger molecules that play a part in how these factors respond to extracellular signals during ischemic injuries. We also provide some new perspectives on how microglial intracellular signaling may contribute to the seemingly contradictory roles of several microglial effector molecules.


2022 ◽  
Vol 11 (2) ◽  
pp. 301
Author(s):  
Neeraja Purandare ◽  
Katherine J. Kramer ◽  
Paige Minchella ◽  
Sarah Ottum ◽  
Christopher Walker ◽  
...  

Adhesions frequently occur postoperatively, causing morbidity. In this noninterventional observational cohort study, we enrolled patients who presented for repeat abdominal surgery, after a history of previous abdominal myomectomy, from March 1998 to June 20210 at St. Vincent’s Catholic Medical Centers. The primary outcome of this pilot study was to compare adhesion rates, extent, and severity in patients who were treated with intraperitoneal triamcinolone acetonide during the initial abdominal myomectomy (n = 31) with those who did not receive any antiadhesion interventions (n = 21), as documented on retrospective chart review. Adhesions were blindly scored using a standard scoring system. About 32% of patients were found to have adhesions in the triamcinolone group compared to 71% in the untreated group (p < 0.01). Compared to controls, adhesions were significantly less in number (0.71 vs. 2.09, p < 0.005), severity (0.54 vs. 1.38, p < 0.004), and extent (0.45 vs. 1.28, p < 0.003). To understand the molecular mechanisms, human fibroblasts were incubated in hypoxic conditions and treated with triamcinolone or vehicle. In vitro studies showed that triamcinolone directly prevents the surge of reactive oxygen species triggered by 2% hypoxia and prevents the increase in TGF-β1 that leads to the irreversible conversion of fibroblasts to an adhesion phenotype. Triamcinolone prevents the increase in reactive oxygen species through alterations in mitochondrial function that are HIF-1α-independent. Controlling mitochondrial function may thus allow for adhesion-free surgery and reduced postoperative complications.


2021 ◽  
Author(s):  
Hayat Ali Alafari ◽  
Magda Abdelgawad

Abstract BackgroundWithin their natural habitat, plants are subjected to abiotic stresses that include heat stress. In the current study, the effect of 4h, 24h and 48h of heat stress on Tetraena propinqua ssp. migahidii seedling’s protein profile and proteomic analyses were investigated. ResultsTotal soluble protein SDS-PAGE profile showed 18-protein bands downregulated at 4h and 48h, however, 20-protein bands were upregulated at 24h of heat stress. A proteomic analysis showed that 81 and 59 targets are involved in gene and protein expression respectively. ConclusionsThe genes and proteins involved in transcription, translation, photosynthesis, transport and other unknown metabolic processes, were differentially expressed under treatments of heat stress. These findings provide insights into the molecular mechanisms related to heat stress, in addition to its influence on the physiological traits of T. propinqua seedlings. Heat stress mediated differential regulation genes indicate a role in development and stress response of T. propinqua. The candidate dual specificity genes identified in this study paves way for more molecular analysis of up- and down-regulation.


1995 ◽  
Vol 42 (2) ◽  
pp. 269-274 ◽  
Author(s):  
U Lenart ◽  
J Haplova ◽  
P Magdolen ◽  
V Farkas ◽  
G Palamarczyk

The membrane-bound sterolglucoside synthase from the yeast Saccharomyces cerevisiae has been solubilized by nonionic detergent, Nonidet P-40, Triton X-100, and partially purified by DEAE-cellulose column chromatography and ammonium sulfate fractionation. SDS/PAGE of the purified fraction revealed the presence of two protein bands of molecular mass 66 kDa and 54 kDa. In an attempt to identify further the polypeptide chain of sterolglucoside synthase, the partially purified enzyme was treated with [di-125I]-5-[3-(p-azidosalicylamide)]allyl-UDPglucose, a photoactive analogue of UDP glucose, which is a substrate for this enzyme. Upon photolysis the 125I-labeled probe was shown to link covalently to the 66 kDa protein. The photoinsertion was competed out by the presence of unlabeled UDPglucose thus suggesting that this protein contains substrate binding site for UDPglucose. Since photoinsertion of the probe to protein of 66 kDa correlates with the molecular mass of the protein visualized upon enzyme purification we postulate that the 66 kDa protein is involved in sterolglucoside synthesis in yeast.


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