Protein Sulfhydryl Research Articles

The use of retinoic acid in association with microneedling in the treatment of epidermal melasma: efficacy and oxidative stress parameters.

This study aimed to evaluate the effectiveness of isolated treatment with retinoic acid and its combination with the microneedling technique in facial melasma, seeking to associate these results with possible oxidative damage. This is a blinded randomized clinical trial with 42 women with facial melasma (skin phototype I-IV), randomized into Group A (microneedling and 5% retinoic acid) or Group B (5% retinoic acid alone). Four procedures were applied with 15days intervals (4 blood collections). Clinical improvement was assessed using the Melasma Area Severity Index (MASI). Serum oxidative stress levels were evaluated by protein oxidation (carbonyl), lipid peroxidation (TBARS) and sulfhydryl groups, as well as enzyme activities of superoxide dismutase (SOD) and catalase (CAT). The statistical analyzes were performed by generalized estimation equation (GEE). There was a reduction in MASI scale and TBARS levels in both groups over time (p < 0.05), with no difference between groups (p = 0.416). There was also a substantial increase in the carbonyl levels at 30days (p = 0.002). The SOD activity decreased after 30days, regardless of group (p < 0.001), which was maintained after 60days. In Group A, there was a reduction in sulfhydryl levels at 60days (p < 0.001). It is important to highlight that both groups demonstrated efficacy in the clinical improvement of melasma within at least 60days, reducing the MASI score by almost 50%. However, microneedling with retinoic acid seems to be the worst treatment because there is a reduction in the non-enzymatic antioxidant defense, which is important to protect against oxidative stress.

Effect of melatonin and folic acid supplementation on the growth performance, antioxidant status, and liver histology of the farmed gilthead sea bream (Sparus aurata L.) under standard rearing conditions.

The present study aimed to investigate the effect of dietary of melatonin (MLT) and folic acid (FA) administrations on growth performance, antioxidant status, and liver histological structure of juvenile gilthead sea bream, Sparus aurata L. under standard rearing conditions. Four diets were considered: a basal diet considered a control and three diets supplemented with 40mg/kg of melatonin (MLT), 2mg/kg of folic acid (FA), and with the mixture of melatonin and folic acid (MLT + FA). Each diet was randomly allocated to triplicate groups of fish (mean initial weight was 2.99 ± 0.55g) for 41days. The obtained results clearly indicated that the melatonin-supplemented diet decreased significantly the growth performance parameters (final body weight, weight gain rate, and specific growth rate) and IGF-1 level of the gilthead sea bream, while the folic acid-supplemented diet has no significant effect on these parameters. The mixture supplementation of melatonin and folic acid has no significant effect on the growth parameters due to the possible interaction between melatonin and folic acid effects. Furthermore, fish fed with all experimental diets showed significantly higher superoxide dismutase activity (SOD) and protein sulfhydryl level (PSH) and lower lipid peroxidation level (TBARS) and catalase activity (CAT) which confirm their powerful antioxidant role. The acetylcholinesterase activity (ACHE) decreased in fish fed with all experimental diets. The underlying mechanisms of driving melatonin and folic acid to reduce acetylcholinesterase activity require further studies. The histological structure of liver of control S. aurata fish shows severe hepatic lipid accumulation in large vacuoles that diminished after dietary individual or mixture folic acid and melatonin supplementations over 41days. This work proved that 2mg/kg of dietary folic acid has a positive effect on the growth performance, oxidative stress defense, and hepatic lipid accumulation reduction in the gilthead sea bream fish. Under our experimental conditions, melatonin failed to improve the growth indexes WGR, SGR, and IGF-I. This study recommends the diet supplementation with a dose lower than 2mg/kg of food due to the observed effects on tissue ACHE activity.

Quercetin treatment increases H2O2 removal by restoration of endogenous antioxidant activity and blocks isoproterenol-induced cardiac hypertrophy.

Oxidative stress, characterized by the accumulation of reactive oxygen species (ROS), is implicated in the pathogenesis of several diseases, including cardiac hypertrophy. The flavonoid quercetin is a potent ROS scavenger, with several beneficial effects for the cardiovascular system, including antihypertrophic effects. Oxidative imbalance has been implicated in cardiac hypertrophy and heart failure. In this work, we tested whether quercetin could attenuate cardiac hypertrophy by improving redox balance and mitochondrial homeostasis. To test this hypothesis, we treated a group of mice with isoproterenol (30mg/kg/day) for 4 or 8 consecutive days. Another group received quercetin (10mg/kg/day) from day 5th of isoproterenol treatment. We carried out the following assays in cardiac tissue: measurement of cardiac hypertrophy, protein sulfhydryl, catalase, Cu/Zn and Mn-superoxide dismutase (SOD) activity, detection of H2O2, and opening of the mitochondrial permeability transition pore. The animals treated with isoproterenol for the initial 4days showed increased cardiac weight/tibia length ratio, decreased protein sulfhydryl content, compromised SOD and catalase activity, and high H2O2 levels. Quercetin was able to attenuate cardiac hypertrophy, restore protein sulfhydryl, and antioxidant activity, in addition to efficiently blocking the H2O2. We also observed that isoproterenol decreases mitochondrial SOD activity, while quercetin reverses it. Strikingly, quercetin also protects mitochondria against the opening of mitochondrial permeability transition pore. Taken together, these results suggest that quercetin is capable of reversing established isoproterenol-induced cardiac hypertrophy through the restoration of cellular redox balance and protecting mitochondria.

Oxidative Stress Biomarkers and Peripheral Endothelial Dysfunction in Rheumatoid Arthritis: A Monocentric Cross-Sectional Case-Control Study.

Previous studies have suggested that oxidative stress may heighten atherosclerotic burden in rheumatoid arthritis (RA), but direct evidence is lacking. Objective: To evaluate the relationship between established plasma oxidative stress biomarkers and peripheral endothelial dysfunction (ED), a marker of early atherosclerosis, in RA. Methods: Paroxonase-1 (PON-1), protein-SH (PSH), and malondialdehyde (MDA) were measured in 164 RA patient s and 100 age- and sex-matched healthy controls without previous cardiovascular events. Peripheral ED, evaluated by flow-mediated pulse amplitude tonometry, was defined by log-transformed reactive hyperemia index (Ln-RHI) values < 0.51. Results: PON-1 activity and PSH concentrations were significantly reduced in RA patients compared to controls. In regression analysis, increased plasma MDA levels were significantly associated with reduced Ln-RHI [B coefficient (95% CI) = −0.003 (−0.005 to −0.0008), p = 0.008] and the presence of peripheral ED (OR (95% CI) = 1.75 (1.06–2.88), p = 0.028). Contrary to our expectations, increased PON-1 activity was significantly associated, albeit weakly, with the presence of ED (OR (95% CI) = 1.00 (1.00–1.01), p = 0.017). Conclusions: In this first evidence of a link between oxidative stress and markers of atherosclerosis, MDA and PON-1 showed opposite associations with peripheral vasodilatory capacity and the presence of ED in RA. Further studies are needed to determine whether this association predicts atherosclerotic events in the RA population.

Gamma irradiation, an effective strategy to control the oxidative damage of soy proteins during storage and processing

Consumption of soybean is dependent on its protein quality and texture which is influenced by protein modification. In the present study, modifications of soybean proteins were investigated by chemical analysis. Irradiation dose of 2.0 kGy resulted in reduced turbidity, surface hydrophobicity and protein oxidation, but caused increase in protein solubility and sulfhydryl contents in both the genotypes. Free phenolics, DPPH and FRAP activites in all the genotypes increased significantly at 2.0 kGy and declined at 5.0 kGy with the exception of DPPH. However, lipoxygenase and bound phenolics decreased with the increase doses of gamma irradiation in both the genotypes tested. To the best of our knowledge this study is the virgin report exploring the use of gamma irradiation for improvement of soybean protein stability, quality and its bioavailability by reducing protein oxidation& modification and/or by enhancing the total inherent antioxidant capacity.

A General Strategy for the Construction of NIR-emitting Si-rhodamines and Their Application for Mitochondrial Temperature Visualization.

Si-rhodamine (SiR) is an ideal fluorophore because it possesses bright emission in the NIR region and can be implemented flexibly in living cells. Currently, several promising approaches for synthesizing SiR are being developed. However, challenges remain in the construction of SiR containing functional groups for bioimaging application. Herein, we introduce a general and simple approach by a condensation reaction of diarylsilylether and arylaldehyde in o-dichlorobenzene to synthesize a series of SiRs bearing various functional substituents. These SiRs have moderate to high quantum efficiency, tolerance to photobleaching, and high water solubility as well as NIR emitting, and their NIR fluorescence properties can be controlled through the photoinduced electron transfer (PET) mechanism. Fluorescence OFF-ON switching effect is observed for SiR 9 in the presence of acid, which is rationalized by DFT/TDDFT calculations. Moreover, reversible stimuli response toward temperature is achieved. Since positive charge enables mitochondrial targeting ability and chloromethyl unit can covalently immobilize the dyes onto the mitochondrial via click reaction between the benzyl choride and protein sulfhydryls, SiR 8 is identified as a valuable fluorescent marker to visualize the morphology and monitor the temperature change of mitochondria with high photostability.

Molecular mechanisms of the effects of N-ethylmaleimide and 1,4-dithioerythritol on regulation of apoptosis in P19 cells under hypoxia

Relevance. Impairment of apoptosis regulation in P19 cells is correlated with generation of oxidative stress. Under hypoxia, changes in mitochondrial functions occur, which may exacerbate oxidative stress in the tumor cell. The aim of the study was to evaluate the effects of N-ethylmaleimide and 1,4-dithioerythritol on implementation and regulation of apoptosis in P19 cells under hypoxia in vitro . Materials and methods . P19 cells (mouse teratocarcinoma) cultured under hypoxia served as the material for the study. For redox status modulation, 5mM N-ethylmaleimide and 1,4-dithioerythritol in the final concentrations of 5 mM were used. The intracellular concentration of calcium ions, the transmembrane potential and the number of Annexin V, CD95 and CD120 positive cells were determined by flow cytometry. The levels of reduced, oxidized and protein-bound glutathione, protein SH groups, hydroxyl radical and protein carbonyl derivatives were measured by spectrophotometry. Results. The alteration in the redox status of the glutathione system under hypoxia, accompanied by oxidative modification of proteins (glutathionylation and carbonylation), influences the metabolism in the tumor cell on the whole. Under the effects of 1,4-dithioerythritol, an SH group protector, this alteration promotes formation of additional mechanisms to escape apoptosis, whereas under the effects of N-ethylmaleimide, an SH group blocker, it, on the contrary, promotes apoptosis activation. Conclusions . The changes in the redox homeostasis of the tumor cell and modulation of oxidative modification of proteins (glutathionylation and carbonylation) under hypoxia are one of the promising approaches to targeted regulation of cell death.

EFFECT OF N-ACETYLCYSTEINE ON APOPTOSIS OF P19 CANCER CELLS DURING HYPOXIA

Introduction. Hypoxia in tumor growth contributes to mitochondrial dysfunction and exacerbates oxidative stress in the immortalized cell. The objective of the study was to investigate the molecular mechanisms of the effects of N-acetylcysteine on redox regulation of tumor cell apoptosis under hypoxia.Material and Methods. P19 cells (mouse teratocarcinoma) cultured under hypoxia served as the material for the study. The redox status was modulated with N-acetylcysteine in the final concentration of 5 mM. The level of reactive oxygen species, concentration of calcium ions, transmembrane potential and the number of CD95-, CD120- and Annexin V-positive cells were determined by flow cytometry. The concentration of glutathione system components as well as the levels of protein SH groups and protein carbonyl derivatives were measured by spectrophotometry.Results. The use of N-acetylcysteine under hypoxic conditions was accompanied by the increased total glutathione concentration and protein SH groups levels, decreased levels of Са2+ ions, proteinbound glutathione and protein carbonyl derivatives, as well as the production of reactive oxygen species and more appropriate functioning of P19 cells mitochondria. N-acetylcysteine contributed to the development of additional resistance of P19 cells to apoptosis under hypoxia.Conclusion. The alteration in the state of the glutathione system under hypoxia influences the changes in tumor cell metabolism on the whole and promotes formation of additional mechanisms to escape apoptosis.

Вплив лазерного опромінення на ксантиноксидазну активність та генерацію супероксидного радикала в цитозольній фракції печінки щурів-пухлиноносіїв

The effect of tumor growth in the body and laser irradiation on the enzymatic activity of xanthine oxidase, in particular its D- and O-forms, and also the rate of generation of the superoxide radical (O2–) and the level of protein sulfhydryl groups in the liver rat cytosolic fraction has been investigated. It has been found that in the cytosolic fraction of rats with transplanted Guerin’s carcinoma decreases the enzymatic activity of the D-form of xanthine oxidase with a simultaneous increase in its O-form during the period of intensive (14 days, which corresponds to the logarithmic phase of on cogenesis) and the period of final tumor growth (21 days, which corresponds to the stationary phase of oncogenesis). The increase in the enzymatic activity of the O-form of xanthine oxidase was accompanied by an increase the rate of superoxide radical generation and a decrease in the level of protein SH-groups in the liver cytosolic fraction of tumor-bearing rats. Daily directed action of laser irradiation on the area of growth of Guerin’s carcinoma leads to less destructive changes in the liver. Thus, there is an increase in the enzymatic activity of the D-form of xanthine oxidase, a decrease the rate of superoxide radical formation and an increase the content of protein SH-groups in the cytosolic fraction of the liver of experimental animals compared with non-irradiated tumor-bearing rats.

A water-soluble and incubate-free fluorescent environment-sensitive probe for ultrafast visualization of protein thiols within living cells

The amount of protein thiols play a crucial role in maintaining the cellular redox homeostasis and have significant implications to indicate a series of diseases. Therefore, it is necessary to develop an ideal probe for protein thiol detection in a simple and readily implementable method. Consequently, a water-soluble and incubate-free fluorescent environment-sensitive probe DMTs-OCC was synthesized using 7-diethylamincoumarin as the fluorophore and 4-(5-Methanesulfonyl- [1,2,3,4]tetrazol-1-yl)-phenol (MSTP) as a thiol receptor reagent. The blue-shift emission spectra of probe DMTs-OCC was observed by ultrafast binding to protein sulfhydryl groups from the excited intramolecular charge transfer (ICT) to the twisted intramolecular charge transfer (TICT) conversion process in aqueous solution. The experimental results showed that probe DMTs-OCC exhibited an excellent selectivity to protein thiols and biocompatibility in aqueous solution, as well as terrific cell membrane permeability which enabled the successful visualization of BSA protein thiol in living cells. Moreover, no excess probe was cleaned and no incubation time was needed in cell experiments. Therefore, it could provide a new method to the construction of fluorescent probes for protein thiols labelling and visualization.

Thiol/disulfide homeostasis in patients with chronic hepatitis B

Aim: The purpose of this study was to evaluate the relation between chronic hepatitis B (CHB) and the thiol/disulfide balance, used as a marker of oxidative stress. Materials and Methods: This study was conducted between May 2016 and July 2016 at the Erzurum Regional Training and Research Hospital Infectious Diseases Polyclinic. 63 subjects with CHB and 60 healthy volunteers without any known diseases were included in the study. In term of measuring dynamic thiol/disulfide homeostasis, we used the novel automated assay method developed by Erel and Neselioglu. Results: Native thiol (SH), total thiol (total SH) and disulfide (SS) levels were determined; measures such as SS/SH, SS/total SH, and SH/total SH were calculated. It is determined that CHB group’s SH levels (P=0.041), total SH levels (P=0.043) were lower than the control group’s. There is negative correlation between Anti-HBc total IgG and total SH, SH, SH/total SH, there is positive correlation between Anti-HBc total IgG and SS/SH, SS/total SH ratio. There is negative correlation between BMX index and total SH, SH, SH/total SH and positive correlation between SS/total SH, SS/SH. Positive correlation is determined between total protein, albumin and total SH, SH. Conclusions: In our study thiol levels as an antioxidant were found to be low in CHB patients. Thiol levels were again emphasized as a new marker in hepatitis B. Thiol levels in CHB are thought to shed light to slowing of disease course and improving new treatment efforts with more wide studies.

Physical Properties and Structural Changes of Myofibrillar Protein Gels Prepared with Basil Seed Gum at Different Salt Levels and Application to Sausages.

The objective of this study was to evaluate physical properties and structural changes of myofibrillar protein gels with basil seed gum (BSG) at different salt levels and develop the low-salt sausages with BSG. Myofibrillar protein (MP) gels were prepared with or without BSG at different salt concentrations (0.15, 0.30, and 0.45 M). Cooking yield (CY, %), gel strength (GS, gf), viscosity, sulfhydryl contents, protein surface hydrophobicity, scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy (FTIR) of MP were measured. Pork sausages were manufactured with 1% BSG at both low-salt (1.0%) and regular-salt (1.5%) levels. pH, color, expressible moisture (EM, %), CY, textural profile analyses, FTIR, sulfhydryl group, and protein surface hydrophobicity (μg) were measured for analyzing the properties of sausages. The addition of 1% BSG to MP gels increased CY and shear stress. Among treatments with different salt concentrations, MP at 0.30 M salt level with 1% BSG had higher GS than that at 0.15 M salt level with BSG. In microstructure, swollen structures were shown in MP gels with BSG. Although CY of sausage at the low-salt concentration (1.0%) decreased, regardless of the BSG addition, hardness values of sausages with regular-salt level increased with the addition of 1% BSG was added. Protein surface hydrophobicity and sulfhydryl contents of sausages increased with the addition of 1% BSG, resulting in higher hardness and lower springiness than those without BSG. These results suggest that BSG could be used as a water-binding and gelling agent in processed meats.

Endocan and advanced oxidation protein products in adult population with hypertension.

Hypertension is closely related to oxidative stress and inflammation. Endocan is a new inflammation marker whose role is not completely elucidated in hypertension. The aim of this study was to explore the association between endocan and several oxidative stress markers [i.e., advanced oxidation protein products (AOPP), total protein sulfhydryl (SH-) groups and prooxidant-antioxidant balance (PAB)] in adult population with hypertension. A total of 90 patients with hypertension were compared with 44 controls. Blood pressure, anthropometric and biochemical parameters were measured. Associations of clinical data with hypertension were tested with univariable and multivariable logistic ordinal regression analysis. Endocan and AOPP were significantly higher in hypertensive patients than in the controls (p=0.006 and p=0.046, respectively). In the multivariable logistic regression analysis, AOPP and endocan kept their independent positive associations with hypertension. As AOPP rose by 1 μmol/L and endocan rose by 1 pg/mL, the probability for hypertension presence rose by 4.2% and 32.2%, respectively and 39.9% of variation in hypertension could be explained with the Model. The area under the Receiver Operating Characteristic curve [(AUC) for AOPP=0.638 (0.550-0.719), p=0.01 and for endocan=0.679 (0.593-0.757), p<0.001] demonstrated sufficient clinical accuracy towards hypertension. On the contrary, the Model showed very good clinical accuracy [AUC= 0.825 (0.749-0.900), p<0.001]. Endocan and AOPP are independently correlated with hypertension in adult population and these tested markers together could be reliable parameters to discriminate patients with hypertension from normotensive ones.

Teratozoospermia: Its association with sperm DNA defects, apoptotic alterations, and oxidative stress.

This study was carried out to evaluate the level of nuclear sperm DNA damage in men with isolated polymorphic teratozoospermiaand examining its relationship with apoptosis and oxidative stress. A total of 89 subjects were divided into two groups: men with isolated teratozoospermia (n=69) and men with normal semen parameters (n=20) as controls. Sperm DNA breaks were determined by using acridine orange staining. The proportion of viable spermatozoa with mitochondrial transmembrane depolarization was detected by fluorescence microscopy through the use of MitoPTJC-1 staining method. Bivariate Annexin V/6-CFDA analysis was then set out in order to measure the percentage of both viable and dead spermatozoa with phosphatidylserine (PS) externalization. Seminal antioxidant profile (reduced glutathione (GSHr); oxidized glutathione (GSSG); glutathione S-transferase (GST)) and total protein sulfhydryl (P-SH) concentrations were measured spectrophotometrically. Men with isolated teratozoospermia, when compared to controls, showed significantly increased level of single sperm DNA breaks and higher proportions of spermatozoa with phosphatidylserine externalization and mitochondrial depolarization. Among the differently studied oxidative stress seminal parameters, the rates of seminal GSHr, GST, and P-SH were significantly decreased in the teratozoospermic group. However, the seminal rates of GSSG and GST have decreased, but only GST did not show a significant difference. Interestingly, significant correlations were found between the studied apoptotic markers and the rate of atypical sperm forms with the incidences of head abnormalities. Furthermore, positive inter-correlations were found between sperm DNA defects, impaired seminal antioxidant status, and the apoptotic sperm markers. Such data provide clear evidence that the apoptotic alterations are closely correlated to abnormal sperm morphology and DNA damage. Moreover, decreased seminal antioxidant profile may be a crucial factor involved in the mechanism of sperm cell death-mediated DNA breaks in teratozoospermic semen.

Response of Bacillus vallismortis sp. EPS to exogenous sulfur stress/ induction and its adsorption performance on Cu(II)

The chemical composition of EPS (Extracellular Polymeric Substances) produced by Bacillus vallismortis sp. and its adsorption performance on typical heavy metal were studied under Na2S stress/induction at different concentrations. Its structure was characterized by three-dimensional fluorescence spectrogram (3D-EEM), infrared spectrum (FTIR) and X-ray photoelectron spectroscopy (XPS). The results showed that, when the Na2S stress/induction intensity was 20 mg/L, the protein concentration was nearly doubled compared with Control-EPS (EPS produced by Bacillus vallismortis sp. without exogenous sulfur stress); furthermore, the 3D-EEM results also demonstrated that there was an increase in the protein content, with the –SH content reaching 154.36 μmol/L, which was 48.2% higher than before stress (104.15 μmol/L). Under this condition, S-EPS (EPS produced by Bacillus vallismortis sp. stressed by exogenous sulfur) exhibited the best adsorption effect on Cu(II), with the theoretical maximum adsorption capacity reaching 1428.57 mg/g EPS. FTIR and XPS analyses revealed that the –SH, CO, N–H played a major role in the adsorption of Cu(II); among those, –SH played a key role. Moreover, the adsorption capacity of Cu(II) by S-EPS was correlated with the content of sulfhydryl protein; indeed, the exogenous sulfur stress/induction can effectively regulate the chemical composition of EPS and improve its adsorption performance, which can be crucial in the prevention and control of heavy metal pollution.

Effects of oxidative modification by 13-hydroperoxyoctadecadienoic acid on the structure and functional properties of rice protein

13-hydroperoxyoctadecadienoic acid (13-HPODE) was selected as lipid peroxidation primary products during rice ageing to investigate the effects of lipid hydroperoxide modification on the structural characteristics and functional properties of rice protein. Incubation of rice protein with 13-HPODE resulted in protein carbonylation and loss of protein sulfhydryl groups in a concentration-dependent manner. FT-IR evaluated the effects of 13-HPODE on rice protein, and the results indicated increasing concentration of 13-HPODE resulted in continuous loss of α-helix, β-turn and random coil structure, and increase in β-sheet content and amino acid side chains. The content of soluble protein aggregates gradually increased, accompanied by protein crosslink via disulfide bonds. 13-HPODE had a negative impact on the solubility, water holding capacity, foaming capacity, and foam stability of rice protein. 13-HPODE could promote oil holding capacity of rice protein. With the concentration of 13-HPODE below 0.1 mmol/L, emulsifying activity index (EAI) and emulsifying stability index (ESI) of rice protein gradually increased, which due to gradual increase in rice protein surface hydrophobicity and flexibility. However, at relatively high concentration of 13-HPODE (above 1 mmol/L), the adverse effect in EAI and ESI was observed, which might be attributed to a decrease in surface hydrophobicity and protein aggregates formation.

The role of açaí ( Euterpe oleracea Mart. 1824) as a chemoprotective agent in the evaluation of antioxidant defence, oxidative damage and histology of juvenile shrimp Litopenaeus vannamei (BOONE, 1931) exposed to ammonia

This study investigated the effects of the use of the inclusion of açaí on the diet of shrimp Litopenaeus vannamei on antioxidant and histopathological responses after exposure to ammonia. The shrimps were fed two experimental diets: control and with 10% of açaí inclusion (W/W), for 35 days. Afterwards, the organisms were exposed at four concentrations of ammonia (0.01-control; 0.26; 0.48 and 0.91 mg NH3-N L−1) for 96 hr. The total antioxidant capacity (ACAP) of the gills decreased significantly in both diets when exposed to ammonia, whereas in the muscle, the açaí promoted an increase in ACAP. Concomitantly, lipid peroxidation levels increased in the gills and decreased in muscle. After exposure to ammonia, glutathione-S-transferase activity increased in hepatopancreas in shrimps fed with açaí facilitating the detoxification of lipid peroxidation by-products, and the concentration of protein sulfhydryl groups decreased in the gills and muscle of the shrimp of the control diet, evidencing protein damage, an unobserved response in shrimps that received the açaí diet. Histopathological changes decreased in açaí-fed shrimps about the control diet after exposure to ammonia. It is concluded that açaí mitigated ammonia-induced histopathological changes, improved the antioxidant defence system (gills and muscle) and attenuated the lipid damage in the muscle.

Oxidative Modifications in Advanced Atherosclerotic Plaques: A Focus on In Situ Protein Sulfhydryl Group Oxidation.

Although oxidative stress has been long associated with the genesis and progression of the atherosclerotic plaque, scanty data on its in situ effects on protein sulfhydryl group modifications are available. Within the arterial wall, protein sulfhydryls and low-molecular-weight (LMW) thiols are involved in the cell regulation of both Reactive Oxygen Species (ROS) and Reactive Nitrogen Species (RNS) levels and are a target for several posttranslational oxidative modifications that take place inside the atherosclerotic plaque, probably contributing to both atherogenesis and atherosclerotic plaque progression towards complicated lesions. Advanced carotid plaques are characterized by very high intraplaque GSH levels, due to cell lysis during apoptotic and/or necrotic events, probably responsible for the altered equilibrium among protein sulfhydryls and LMW thiols. Some lines of evidence show that the prooxidant environment present in atherosclerotic tissue could modify filtered proteins also by protein-SH group oxidation, and demonstrate that particularly albumin, once filtered, represents a harmful source of homocysteine and cysteinylglycine inside the plaque. The oxidative modification of protein sulfhydryls, with particular emphasis to protein thiolation by LMW thiols and its association with atherosclerosis, is the main topic of this review.

Role of Zinc Supplementation on Ischemia/Reperfusion Injury in Various Organs.

Ischemia-reperfusion (I/R) injury is a serious condition which is associated with myocardial infarction, stroke, acute kidney injury, trauma, circulatory arrest, sickle cell disease, and sleep apnea and can lead to high morbidity and mortality. Salts of zinc (Zn) are commonly used by humans and have protective effects against gastric, renal, hepatic, muscle, myocardial, or neuronal ischemic injury. The present review evaluates molecular mechanisms underlying the protective effects of Zn supplement against I/R injury. Data of this review have been collected from the scientific articles published in databases such as Science Direct, Scopus, PubMed, and Scientific Information Database from 1991 to 2019. Zn supplementation increased the decreased parameters including superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX), glutathione (GSH), metallothionein (MT), protein sulfhydryl (P-SH), and nuclear factor-erythroid 2-related factor-2 (Nrf2) expression and decreased the increased elements such as endoplasmic reticulum (ER) stress, mitochondrial permeability transition pore (mPTP) opening, malondialdehyde (MDA), serum level of aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), lactate dehydrogenase (LDH), and microRNAs-(122 and 34a), apoptotic factors, and histopathological changes. Zn also increases phosphatidylinositol 3-kinase (PI3K)/Akt and glycogen synthase kinase-3β (GSK-3β) phosphorylation and preserves protein kinase C isoforms. It is suggested that Zn can be administered before elective surgeries for prevention of side effects of I/R injury.

Evaluation of the Putative Efficacy of a Methanolic Extract of Ocimum Basilicum in Preventing Disruption of Structural Proteins in an in Vitro System of Selenite-induced Cataractogenesis

ABSTRACTPurpose: To evaluate whether a methanolic extract of Ocimum basilicum (OB) leaves prevented lenticular protein alterations in an in-vitro model of selenite-induced cataractogenesis.Materials and Methods: Transparent lenses extirpated from Wistar rats were divided into three groups: control; selenite only; treated. Control lenses were cultured in Dulbecco’s modified Eagle’s medium (DMEM) alone, selenite only lenses were cultured in DMEM containing sodium selenite only (100 µM selenite/ml DMEM) and treated lenses were cultured in DMEM containing sodium selenite and the methanolic extract of OB leaves (200 µg of extract/ml DMEM); all lenses were cultured for 24 h and then processed. The parameters assessed in lenticular homogenates were lenticular protein sulfhydryl and carbonyl content, calcium level, insoluble to soluble protein ratio, sodium dodecyl sulphate-polyacrylamide gel electrophoretic (SDS-PAGE) patterns of lenticular proteins, and mRNA transcript and protein levels of αA-crystallin and βB1-crystallins.Results: Selenite only lenses exhibited alterations in all parameters assessed. Treated lenses exhibited values for these parameters that were comparable to those noted in normal control lenses.Conclusions: The methanolic extract of OB leaves prevented alterations in lenticular protein sulfhydryl and carbonyl content, calcium level, insoluble to soluble protein ratio, SDS-PAGE patterns of lenticular proteins, and expression of αA-crystallin and βB1-crystallin gene and proteins in cultured selenite-challenged lenses. OB may be further evaluated as a promising agent for the prevention of cataract.