Gluthatione Peroxidase Research Articles

Olive oil increase catalase activity and gluthatione peroxidase level in hyperglycemic rats

Background: Diabetes mellitus is the most common endocrine disease globally. Hyperglycemia in diabetes mellitus is known to trigger oxidative stress. The activity of glutathione peroxidase (GSH-Px) is decreased in diabetic conditions. Catalase activity acts as a defense system to prevent the formation of free radicals (oxidants) in the human body. Objective: This study aimed to determine the effectiveness of olive oil antioxidants on catalase activity and GSH-Px levels in hyperglycemic rats. Methods: Adult male Wistar rats were randomized into three groups (n: 8): untreated control (Control), alloxan-induced untreated (Alloxan), and alloxan-induced treatment (Treatment) of olive oil at 25 mL/day for 14 days. Catalase activities were measured using the spectrophotometry method, and GSH-Px levels were analyzed using an enzyme-linked immunosorbent assay (ELISA). Results: Administration of olive oil increased catalase activity compared to the untreated group in alloxan-induced rats. The average level of glutathione peroxidase was higher in the treatment group than in alloxan-induced rats. Conclusion: Antioxidants in olive oil increased catalase activity and glutathione peroxidase levels in alloxan-induced hyperglycemic rats.

Effect of Citrus maxima (Shaddock) fruit juice on some oxidative stress parameters in CCl4 induced oxidative stress in wistar rats

This study was designed to evaluate the in vivo anti-oxidative stress potentials of Citrus maxima juice. Thirty six wistar rats were divided into nine groups. Group 1 served as the normal control. Groups 2-5 which served as the protective study groups were treated from day 1 to 14 of experiment, and administered Carbon tetrachloride on days 13 and 14. Groups 6-9 served as the curative study groups and were administered Carbon tetrachloride on days 0 and 1 of the experiment and treated from day 1 to 14. All animals were sacrificed on the 15th day after a 14-16 hour overnight fast and blood sample collected through ocular bleeding for biochemical analyses. Intoxication with Carbon tetrachloride decreased significantly (p>0.05) the activities of the antioxidant enzymes - Superoxide dismutase, Gluthatione peroxidase and Catalase. Administration of CMJ increased non-significantly (p>0.05) the activities of the antioxidant enzymes.

Effect of increased levels of dietary α-linolenic acid on the n-3 PUFA bioavailability and oxidative stress in rat.

We investigated the impact of increased alpha-linolenic acid (ALA) dietary levels on its plasma bioavailability and its bioconversion in n-3 long chain poly unsaturated fatty acids during a 60-d kinetics and the oxidative stress potentially associated. Rats were submitted to a normolipidic diet providing 0, 3, 10 and 24% ALA of dietary lipids for 0, 15, 30 and 60 days. The lipid peroxidation and oxidative stress (nitric oxide (NO) contents and catalase (CAT), superoxide dismutase (SOD), gluthation peroxidase (GPx) activities) were studied in the liver and plasma. When the diet was deprived in n-3 PUFAs, ALA, (eicosanoic acid) EPA and docosahexaenoic acid (DHA) levels decreased in all lipid fractions of plasma and in red blood cell (RBC) lipids. The addition of ALA in the diet linearly improves its bioavailability and its bioconversion in EPA (R²=0.98). By providing 10 to 24% ALA in dietary lipids (LA/ALA, 1·6 and 5·5 respectively), ALA and EPA were more broadly packaged in all lipid fractions (triglyceride (TAG), cholesterol ester (CE) and free fatty acids (FFA)) of plasma from 15 to 30 days timeframe. Only 3% ALA was sufficient to promote the maximal bioconversion of ALA in DHA in phospholipid (PL) and TAG fractions. Additionally, the improvement of ALA bioconversion in EPA and DHA did not impact the oxidative stress markers and limiting lipid peroxidation. To conclude, this study demonstrated that in rat, 10% ALA in the lipid diet for 15-30 days promotes its bioavailability and its bioconversion and allowed the greatest levels in plasma and RBCs.

Artemisia restores systolic blood pressure, attenuates serum sodium/potassium levels and prevents cardiac oxidative stress in hypertension

PurposeThis paper aims to evaluate systolic blood pressure (SBP), serum sodium/potassium levels and cardiac antioxidants after Artemisia herba-alba oral administration in spontaneous hypertensive rats (SHR).Design/methodology/approachHypertension is a silent killer disease. The SHR model was used in this study due to the similarity of high blood pressure in human and rat. The SBP, serum sodium and potassium, urinary sodium and potassium, cardiac antioxidants and heart histology were examined in SHR after oral administration with 10 and 20% of the LD50 of Artemisia herba-alba during four weeks.FindingsThe LD50 of Artemisia herba-alba was found to be 1000 mg/kg. Doses of 100 mg/kg (10% LD50) and 200 mg/kg (20% LD50) were considered in the present study. The oral administration of SHR rats with Artemisia extract at 100 and 200 mg/kg decreased (p < 0.01) the body weights, SBP and serum sodium and potassium. Meanwhile, cardiac superoxide dismutase and gluthatione peroxidase were increased in SHR-treated rats. Histology of SHR cardiac tissues showed tissue degenerative but oral intake of 100 and 200 mg/kg artemisia exhibited normal muscle fibers, acidophilic cytoplasm and central nuclei.Originality/valueThe cardiovascular diseases are the first reason for high death rate in Western countries and collapsing economies due to hypertensive patients suffering high health-care costs. The advantage of hypertension Herba l treatment occurred due to its cheap and available source. Artemisia herba-alba leaves restored SBP, attenuated serum sodium/potassium levels and prevented cardiac oxidative stress in SHR.

How macroalgae can deal with radiation variability and photoacclimation capacity: The example of Gracilaria tenuistipitata (Rhodophyta) in laboratory

Radiation continuously varies in the environment, exposing phototrophic organisms to diverse compositions and ratios among photosynthetically active radiation (PAR), UV-A (Ultraviolet A radiation) and UV-B (Ultraviolet B radiation). In this sense, UV radiation can control, either positively or negatively, the physiology and metabolism of marine organisms in intertidal areas. Our study focused on the exposure of Gracilaria tenuistipitata to variable combinations of radiation, evaluating its physiology, photoprotective strategies and DNA damage under each condition. To accomplish this, algal apical fragments were acclimated to three radiation treatments (PAR, PAR + UV-A and PAR + UV-A + UV-B) for one week. Thereafter, PAR-acclimated samples were moved to PAR (control), PAR + UV-A + UV-B and PAR + UV-B. PAR + UV-A-acclimated samples were moved to PAR + UV-A (control), PAR + UV-A + UV-B and PAR + UV-B, and PAR + UVR-acclimated thalli were placed in PAR + UV-A + UV-B (control), PAR + UV-B and PAR. Samples remained in these conditions for a period of 48 h continuously. Photosynthetic parameters from chlorophyll a fluorescence were evaluated, as well as growth rates, mycosporine-like amino acids, chlorophyll a, and carotenoid contents. In addition, DNA damage was assessed by detecting cyclobutane pyrimidin dimer. Expression of photolyases, ascorbate peroxidase and gluthatione peroxidase was also analyzed at the end of experimental period. Mycosporine-like amino acids were stimulated by UV radiation. DNA damage occurred only when UV-B was provided separately. In some cases, photoacclimation procedures were activated, while in others, it was not enough. In other words, although some tolerance was observed, the species could suffer the consequences of excessive energy present in some specific treatments, e.g., PAR + UV-B. After exposure to variable radiation, it was concluded that our model organism presented acclimation depending of spectral availability, including regulation of photoprotective strategies.

Protective effect of genistein in a rat model of ischemic acute kidney injury.

This study determined the possible anti-inflammatory and antioxidant renal protective effect of genistein, a soy isoflavone, against kidney damage and functional disorders following renal ischemia/reperfusion (I/R) in male rats. The animals were dedicated to five groups (n=7 per group): Sham, Sham+Geni (genistein, 15mg/kg in 1ml 1% DMSO, i.p.), Sham+DMSO (1ml 1% DMSO, i.p.), I/R (bilateral renal ischemia for 45min followed by 24h reperfusion), I/R+Geni (genistein, 15mg/kg). 24-h urine samples, blood and tissue samples of the kidney were collected at the end of 24h reperfusion period. Compared to sham, sham+Geni and sham+DMSO groups, IR injury (IRI) ended in kidney dysfunction (decreased creatinine clearance, and increased fractional excretion of sodium), increased levels of malondialdehyde, decreased activities of antioxidant enzymes (superoxide dismutase, gluthatione peroxidase, and catalase), increased gene expression levels of TLR4 (Toll-like receptor 4) and TNF-α (tumor necrosis factor-alpha), as well as histological damages in kidney tissue. Genistein administration decreased all the changes. Therefore, genistein apparently protects the kidney against IRI by mitigating both oxidative stress and inflammation. The antioxidant and anti-inflammatory properties of genistein probably exert important roles in improving functional disorders and offer renal protection against IRI.

In vitro and in vivo Antioxidant Properties of Extracts from the Root of Curcuma longa Linn

Many plants possess antioxidants that exhibit additive or synergistic activities. The antioxidant activities of the root of Curcuma longa Linn extracts extracted different solvents were investigated by using several established in vitro systems: α,α-diphenyl-β-picrylhydrazyl (DPPH) radical scavenging activity, hydrogen Peroxide scavenging activity (HPSA), nitric oxide radical scavenging activity (NOSA) and ferric reducing antioxidant power (FRAP). The result showed that methanol extract exhibited greater antioxidant activity in vitro which was statistically significant compared to the other extracts. Based on the in vitro results, the methanol extract was subjected to column chromatography. Six pooled fractions (FI-FVI) were evaluated for in vivo antioxidant activity in liver and kidney of alloxan-induced diabetic rats using a total of forty-five (45) rats which were grouped into nine (9) groups of five (5) rats. The in vivo antioxidants showed a significant decrease in superoxide dismutase (SOD), catalase (CAT) and gluthatione peroxidase (GPx) levels in both liver and kidney of Alloxan-induced diabetic rats. These changes were significantly reversed after treatment with methanol fraction II and the standard drug. Thus, Curcuma longa Linn may be useful in the management of diabetes and oxidative stress.

Reducing stress by improving performance of hatchery-reared Catarina scallop (Argopecten ventricosus) spat with different genera of beneficial microorganisms: A biochemical and molecular analysis

This study investigated the probiotic effects of one lactobacillus, one marine yeast, mix of three bacilli and mix of all probiotic strains on the growth, survival, antioxidant response (superoxide dismutase = SOD, catalase = CAT, gluthatione peroxidase = GPX) and immune response (lysozyme = LYZ, heat shock protein =HSP70) of hatchery-reared Catarina scallop Argopecten ventricosus early spat. The spat was exposed every three days for 28 days to a single dose of 1 × 106 CFU mL–1 of one of five treatments used in triplicate: (1) Lactobacillus plantarum (C3); (2) Candida cretensis (S10); (3) Mix of Bacillus cereus, Bacillus flexus, and Bacillus firmus (BMix); (4) Mix of 1 + 2+3 (LLBMix); (5) Group of spat without probiotics as control. Survival was 100 % in all probiotic treatments and the control group. The spat treated with the yeast (S10) and lactobacillus (C3) significantly increased absolute growth and growth rate compared to the control. The antioxidant activity and gene expression was significantly lower in all spat treated with probiotics than in the control group, particularly with the BMix, LLBMix (SOD), C3 (CAT, GPX), and BMix (CAT) strains. The immune activity and gene expression was also significantly lower in spat treated with probiotics, particularly BMix, LLBMix (LYZ), C3, BMix, and S10 (HSP70) strains, compared to the control group. The use of a single dose of probiotic or mix of different strains reduced activation of antioxidant and immune response and improved overall performance of hatchery-reared A. ventricosus spat.

N-Acetyl-Cysteine supplementation lowers high homocysteine plasma levels and increases Glutathione synthesis in the trans-sulfuration pathway

Glutathione (GSH), a compound derived of a combination of three amino acids – cysteine, glycine and glutamine – is the final product of homocysteine (Hcy) metabolism in the transsulfuration pathway. The major determinants of GSH synthesis are the availability of cysteine and the activity of the rate-limiting enzyme, glutamate cysteine ligase (GCL). A deficiency in transsulfuration pathway leads to excessive Hcy production (HHcy) and reduced GSH synthesis. This tripeptide, that exists in the reduced or active form (GSH) and oxidized variant (GSH), is the main antioxidant of the body. Independently of its antioxidant function, the compound has an anti-inflammatory role too, reducing the production of interleukines and the expression of TNF-alfa and iNOS synthase. A dysregulation of GSH synthesis is recognized as contributing factor to the pathogenesis of many pathological conditions. But, the insufficiency of the transsulfuration pathway is also responsible of HHcy. Besides, this condition decreases the activity of cellular “gluthatione peroxidase”, an intracellular antioxidant enzyme that reduces hydrogen peroxide to water with the prevalence of GSSH on GSH. The consequent GSH/GSSH impaired ratio also causes some common cardiovascular and neurodegenerative disorders. In both occurrences, N-Acetyl-Cysteine (NAC) supplementation supplies the cysteine necessary for GSH synthesis and contemporarily reduces HHcy, improving the GPx1 activity and further reducing oxidative stress.

A New Role of Glutathion Peroxydase 4 in Human Erythroblast Enucleation

The Gluthation peroxidase (GPX) enzymes are part of the protective system against lipid peroxydation that includes prevention of oxydation and reduction of already oxidized lipid through enzymatic reactions catalyzed by GSH. GPX4 is one of the five GPX able to incorporate selenium. It is also the only GPX able to directly reduce in the membrane the oxidized fatty acids and cholesterol. Recent reports identified GPX4 as the central inhibitor of ferroptosis, a process during which iron-induced peroxydation of membrane lipids causes a specific cell death that can be reverted by lipophilic antioxydants or by iron chelators. GPX4 has recently been involved during mice erythropoiesis: GPX4-/-mice present a hemolytic anemia and a high apoptotic rate in spleen erythroid progenitors. Although transcriptomics and proteomics found it expressed in human erythroid precursors, its role during human erythropoiesis has not been described. Using an in-vitroerythroid differentiation protocol from CD34+cells obtained from apheresis, we confirmed that GPX4 expression was induced at RNA and protein level during differentiation. RSL3, a specific GPX4 inhibitor, didn't affect early steps of erythropoiesis (i.eclonogenic potential and progenitor amplification) nor the early maturation of erythroid precursors (assessed by sequential CD49d/CD235/CD71 staining) but led to a significant decrease in the enucleation rate as assessed by Hoechst staining using flow cytometry (74%±9 DMSO versus 35%±6 RSL3, p&amp;lt;0.01) and by cytology after MGG staining (58%±10 DMSO versus 27% RSL3±5, p&amp;lt;0.05). This effect was not related to ferroptosis since (i) FIN56 and erastin, two other ferroptosis activators, didn't impact enucleation and (ii) the enucleation defect was not reverted by tocopherol or ferrostatin. Of note, tocopherol reverted lipid peroxydation at cell surface, as shown by Bodipy-C11 staining, showing that enucleation defect and lipid peroxydation were not directly related. These data argue for a specific GPX4 role in the enucleation process, independently to its well-described function in ferroptosis control. Using Western Blot, we observed that RSL3 exposure induced a strong GPX4 depletion in erythroid progenitors while it didn't affect GPX1, another member of the GPX family expressed in erythroid cells. In order to confirm that enucleation defect was related to GPX4 knockdown, we used an Sh-RNA strategy that allowed a 62%±6 GPX4 decrease at RNA level and a 46%±5 at protein level. We observed a significant defect in terminal enucleation in the cells transduced with shGPX4-lentiviruses in comparison with sh-Scramble (59%±5 Sh-Scr versus 39%±6 Sh-Gpx4, p&amp;lt;0.05). Isopentylpyrophosphate, an intermediate component of cholesterol synthesis that also acts as a substract of selenoprotein synthesis, restored partially both GPX4 expression and erythroblast enucleation. We investigated then whether GPX4-knock-down affected quantitatively or qualitatively the membrane lipid content, which was shown to be involved in the enucleation process. Addition of Cholesterol to RSL3 in the medium partially restored the enucleation rate. However, lipidomics failed to show any significant difference in the total membrane lipid content (and particularly in the cholesterol content) after RSL3 exposure in comparison to DMSO. Since cholesterol is particularly abundant in the lipid rafts, we investigated whether the lipid distribution was qualitatively altered within the cell membrane. We observed a disruption of membrane lipid rafts when cells were exposed to RSL3, as shown by a 60%±12 decrease in the mean cholera toxin fluorescence intensity. GPX4 presence in lipid rafts was confirmed using immunofluorescence showing their co-localization at cell surface in human primary erythroblasts. Since lipid rafts play a role in the contractile ring that separates pyrenocyte from reticulocyte, we evaluated the myosin-light chain phosphorylation using flow cytometry and Western Blot and found it drastically decreased in GPX4-knockdown conditions. In summary, we identified GPX4 as a new actor of human terminal erythroid differentiation, independently to its function in ferroptosis control. We described its interaction at cell surface with lipid rafts that are required for the assembly of the contractile ring and cytokinesis leading to the nucleus extrusion. Disclosures No relevant conflicts of interest to declare.

Investigation of the response to salinity of transgenic potato plants overexpressing the transcription factor StERF94

Salinity is one of the most important constraints threatening the cultivation of potato plants (Solanum tuberosum L.). It affects plant growth and leads to significant yield loss. Consequently, it is important to improve the tolerance of potato plants to salinity. In this context, we investigated the involvement of a potato ethylene responsive factor (StERF94) in plant response to salinity, since our previous genome-wide analysis showed that it may be related to biotic and abiotic stress response. ERF proteins belong to a large family of transcription factors that participate in plant response to abiotic stresses. We have previously identified the StERF94 gene which shows increased expression in potato plants submitted to salt treatment. In this study, transgenic potato plants overexpressing StERF94 were produced and submitted to salt treatment (100 mM NaCl) in vitro and under greenhouse culture conditions. StERF94 transgenic lines showed lower decrease of stem elongation under salt treatment in comparison to non-transgenic wild-type plants. Moreover, these plants showed a low level of H2O2 and Malondialdehyde content, and an increase in catalase and GPX (Gluthation peroxidase) activities compared to non-transgenic plants. In a second step, enhanced expression of some target genes for example CuZn-SOD, DHN25 (Dehydrin) and ERD (Early Responsive to Dehydration) was noted in the StERF94 transgenic plants, submitted to salt treatment. The StERF94 factor was also involved in the activation of osmoprotectant synthesis. Taken together, all these data suggest that overexpression of the StERF94 transcription factor increases the tolerance of potato plants to salinity by improving plant growth, osmoprotectant synthesis and antioxidant activityleading to low oxidative stress damage.

The effect of diosmin against liver damage caused by cadmium in rats.

A total of 40, male Wistar Albino, 2-3-months-old rats were used and divided into four groups. Control group received the vehicle alone, diosmin group received 100mg/kg.bw diosmin, the cadmium group received 200ppm cadmium, cadmium plus diosmin group received 200ppm cadmium, and 100mg/kg.bw diosmin for 30days. Some biochemical parameters (aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, and lactate dehydrogenase) and oxidative stress parameters (malondialdehyde [MDA], nitric oxide [NO], superoxide dismutase [SOD], catalase [CAT], gluthatione peroxidase [GSH-Px], and glutathione [GSH]) were analyzed in the samples. Histo-pathological findings were evaluated in the liver. The body weights and liver weights of the animals were measured. The MDA and NO levels and biochemical enzyme activities examined were increased, whereas SOD, CAT, and GSH-Px activities and GSH levels decreased in cadmium-exposed group. There were also negative changes in body weight, liver weight, and liver tissue histo-phathology. Positive improvements were observed in all these parameters evaluated of the group co-administered cadmium and diosmin. PRACTICAL APPLICATIONS: Cadmium is one of the common environmental pollutants. Diosmin is a type of flavonoid found mainly in citrus fruits. It can also be produced from hesperidine. This compound is used for medical purposes and also has strong antioxidant properties. One of the toxic effects mechanisms of cadmium is oxidative stress and causes liver damage with different pathways. This compound can be used as a supporting agent in addition to the main treatment options against liver damage in case of exposure to possible cadmium. This flavonoid can also be taken with food for prophylactic purposes.

Exercise training initiated at old stage of lifespan attenuates aging-and ovariectomy-induced cardiac and renal oxidative stress: Role of baroreflex.

The association of aging and menopause is a potent risk factor for cardiometabolic disease. We studied the impact of aerobic exercise training (ET) initiated in the old stage of lifespan in hemodynamics, metabolic, autonomic and oxidative stress. Aged (18 months old) female Wistar rats were divided into: ovariectomized and untrained (AG-OVX), and ovariectomized and trained (AG-OVXt, ET for 8 weeks). Intact aged (AG) and young female rats (3 months old; Y) were also studied. Blood pressure and metabolic parameters were measured. Baroreflex sensitivity (BRS) was studied by bradycardic (BR) and tachycardic (TR) responses to vasoactive drugs. Cardiac and renal lipid peroxidation (LPO), catalase (CAT), superoxide dismutase (SOD) and gluthatione peroxidase (GPx), and gluthatione redox balance (GSH/GSSG) were analyzed. AG-OVXt group increased aerobic performance in 35%, decreased adipose tissue and triglycerides in 36% and 27%, respectively, and improved insulin tolerance in 50% in comparison to AG-OVX. AG-OVX presented hypertensive levels of blood pressure (systolic: 155 ± 5, diastolic: 111 ± 3 mmHg). In contrast, AG-OVXt presented blood pressure values similar to Y rats (systolic: 129 ± 3, diastolic: 112 ± 3 mmHg). TR and BR were reduced by 70% and 46%, respectively, in AG-OVX vs. Y. Once more, AG-OVXt presented similar results to Y. ET decreased LPO in the heart and kidney. In the latter, renal CAT and SOD were corrected by ET, while cardiac redox balance was partially recovered. Improved BRS was correlated with improved oxidative stress markers. Even when initiated after aging and ovariectomy deleterious effects, ET is able to normalize BRS and highly improve cardiac and renal oxidative stress.

Chemical composition of propolis extract and its effects on epirubicin-induced hepatotoxicity in rats

Propolis is a natural substance, produced by honeybees from the resin of various plants. The purpose of this study was to determine the chemical composition and evaluate the hepatoprotective effect of ethyl acetate extract of propolis from Tigzirt, against the toxicity induced by epirubicin which is a anticancer agent, and belongs to the family of antracyclines. The study included thirty male Wistar albino rats divided into five groups. The rats received the extraction of propolis or the quercetin orally for 15 days. The hepatotoxicity was promoted by injection epirubicin (i.v.) with a cumulative dose of 9mg/kg. Several biological parameters were measured. Oxidative status was also assessed by evaluating antioxidant enzyme and histological study of some organs. Epirubicin caused oxidative stress by a significant decrease in hepatic antioxidant enzymes (gluthation peroxidase, catalase, superoxide dismutase), increased malondialdehyde and liver parameters (ASAT, ALAT, γGT, ALP) compared to the control. The histological study revealed major damage to the liver. Perturbations in this liver function, antioxidant status and damage to the liver by epirubicin have been repaired by the administration of propolis. Furthermore, epirubicin showed inflammatory effects induced by an increase in TNF-α and PGE2. Pretreatment with propolis to rats restored these inflammatory parameters. The chemical identification of extract of propolis by HPLC/UV shows the presence of polyphenolic compounds and many flavonoids. The propolis extract showed a significant reduction in oxidative damage from oxidative stress and a very important protective effect against epirubicin-induced hepatotoxicity.

Demethylation of the hypoxia induction factor 1 binding site of GPX3 at excess blood ammonia in propionic acidemia

ObjectivesElevated levels of metabolites such as ammonia and propionylcarnitine in propionic acidemia (PA) lead to an increased reactive oxygen species (ROS) production which could activate and stabilize the epigenetic regulated hypoxia-inducible factor-1α (HIF-1α). In order to evaluate the DNA methylation status of the HIF-1α binding site in PA, we investigated the antioxidant gluthatione peroxidase 3 gene (GPX3) promoter region. Design and methodsUsing leukocyte DNA extracted from bloodspots collected 2–4 days after birth from diet free newborns, the cytosine phosphodiester bond guanine (CpG) dinucleotides of a HIF-1α binding site (CGTTTTTTACG) in the promoter region of GPX3 was retrospectively analysed. Patients included 7 PA.and 7 healthy controls (KO) respectively. ResultsA demethylated TGTTTTTTATG allele was detected in 3 PA patients with blood ammonia (NH3) concentrations of 500, 595, and 987 umol/L respectively; a demethylated/partial methylated TGTTTTTTAC/TG allele in 4 PA patients (2 PA with blood NH3 = 213, 271 umol/L respectively); a partial methylated C/TGTTTTTTAC/TG allele in 5 healthy controls respectively; a partial methylated/methylated C/TGTTTTTTACG allele in 2 healthy controls. ConclusionOur results suggest that at excess NH3, the DNA methylation status of the HIF-1α binding site of GPX3 in newborns with PA is demethylated (TGTTTTTTATG allele). However, the demethylated allele has to be confirmed as a statistically significant change in more patients.

Berberine ameliorates experimental varicocele-induced damages at testis and sperm levels; evidences for oxidative stress and inflammation.

The present study was performed to show the ameliorative effect of berberine (BBR), as an antioxidant and anti-inflammatory agent, against experimental varicocele (VCL)-induced molecular and histological damages. For this purpose, 50 mature Wistar rats were divided into control, control-sham, VCL-sole, 50mg/kg and 100mg/kg BBR-treated VCL-induced groups. The tissue levels of interleukin-6 (IL-6), tumour necrosis factor-α (TNF-α), nitric oxide (NO), total antioxidant capacity (TAC), malondialdehyde (MDA), superoxide dismutase (SOD) and gluthatione peroxidase (GSH-px) as well as the mRNA levels of testicular CuZn SOD, MnSOD, EC-SOD and GSH-px were evaluated. The serum concentration of testosterone and germ cells mRNA damage were analysed. Finally, the sperm viability, motility, DNA integrity and chromatin condensation were analysed. Observations revealed that, the BBR significantly downregulated VCL-increased IL-6, TNF-α and NO levels, upregulated the CuZn SOD, MnSOD, EC-SOD and GSH-px mRNA level, decreased testicular MDA content, enhanced serum testosterone level and ameliorated testicular TAC, SOD and GSH-px levels. The animals in BBR-treated groups exhibited diminished mRNA damage versus non-treated VCL-induced group. The BBR has significantly (p<0.05) improved sperm parameters. In conclusion, the BBR by promoting testicular antioxidant potential and by downregulating inflammatory reactions fairly promotes spermatogenesis and upregulates the sperm quality.

CAT-262CT Genotype shows higher catalase activity in seminal plasma and lower risk of male infertility

Catalase (CAT), the key enzyme for high H2O2 elimination, constitutes, along with superoxide dismutase (SOD) and gluthatione peroxidase (GPX), the main enzymatic antioxidant system. Catalase enzyme plays an important role in seminal antioxidant defence and is present in seminal plasma at high concentrations. Low concentrations of catalase enzyme in seminal plasma have been related with male infertility. The objective of this study was to evaluate the correlation between the CAT C-262T polymorphism and male infertility. Semen samples from 400 infertile patients and 80 donors with proven fertility were included in the study. Standart semen parameters, DNA integrity and oxidative stress were evaluated. Genotype frequencies for the CAT C-262T polymorphism were determined by PCR-RFLP. Catalase concentration and activity in seminal plasma were evaluated by western-blot and activity gels respectively while catalase mRNA levels in mature spermatozoa were evaluated by qPCR. The CC genotype was associated with an increased risk of male infertility (OR = 1.976; CI = 1.241–3.216; P = 0.006) while the CT genotype was associated with a protective effect against infertility (OR = 0.479; CI = 0.293–0.783; P = 0.003). Functionally, the CT genotype showed higher concentrations of the enzyme in seminal plasma as well as 2.70 times higher activity levels than the CC genotype. Also, the CT genotype showed 3.5 higher levels of CAT mRNA in the mature spermatozoa than the CC genotype. This suggests that the CAT -262CT genotype correlates with a lower risk of suffering male infertility.

Cerebellar adrenomedullin: A new target for blood pressure regulation

Adrenomedullin (AM) and their receptor components, CRLR, RAMP1, RAMP2 and RAMP3 are widely expressed in the central nervous system, including cerebellum. Recent evidence suggests a role for cerebellar adrenomedullinergic system in blood pressure (BP) regulation. We assessed AM, RAMP1, RAMP2, RAMP3 and CRLR expression; and AM receptor signaling pathway in the cerebellar vermis of WKY and SHR rats. Our findings demonstrated that CRLR, RAMP1 and RAMP3 expression was higher in cerebellum of SHR rats, while AM and RAMP2 expression was lower than those of WKY rats, both in 8 and 16 week old rats. In regard of AM signaling pathways, we show that AM activates ERK, increases cAMP production, increases cGMP production and NO accumulation. These effects are mediated through the activation of AM 1 receptor, since AM 22-52 blunted AM action, meanwhile AM increase of cAMP production is also mediated through stimulation of AM2 and CGRP receptors. Furthermore, AM decreased TBARS production and antioxidant enzymes basal activity: catalase (CAT), gluthation peroxidase (GPx) and superoxide dismutase (SOD). During hypertension, AM signaling pathways in the cerebellar vermis are altered. Effectively, in WKY rats AM decreased the activity of three antioxidant enzymes and TBARS production, while in SHR rats AM was unable to affect these signaling pathways; AM-induced ERK1/2 activation in cerebellum of the SHR was smaller in magnitude than in WKY; and AM increased cGMP/NO production in cerebellar vermis of the WKY rats, while in SHR rats AM was unable to stimulate this signaling pathway. We anticipated a possible functional role of cerebellar AM on BP regulation. Indeed, in vivo microinjection of AM into the cerebellar vermis caused a profound, dose dependent, hypotensive effect in SHR but not in normotensive WKY rats. Co-injections of a putative AM receptor antagonist, AM 22–52 abolished the decreases in MAP evoked by AM, showing that AM acts through its AM1 receptor to reduce blood pressure. These findings demonstrate dysregulation of cerebellar AM system during hypertension, and suggest that cerebellar AM plays an important role in the regulation of BP. Likewise, they constitute a novel mechanism of BP control which has not been described so far.

P-195 - Oxidative stress parameters as markers of the rate of aging and longevity in mice

Given the different rate of aging of each individual, it is necessary to find valid biomarkers for measuring biological age. In this sense parameters of oxidative stress could be useful. Moreover, it has been shown that there is an age-related decrease in antioxidant as well as an increase in oxidant compounds. Due to the difficulty of carrying out longitudinal studies in humans, all parameters suitable as markers of biological age, have to be validated using experimental animals. Therefore, antioxidant (Catalase, Gluthatione Peroxidase and Gluthatione Reductase activities and GSH levels), oxidant (GSSG and superoxide anion) and malondialdehyde levels were studied in murine peritoneal immune cells at the adult, mature, old, very old and long-lived ages, in a longitudinal study. The results show decreased antioxidant defenses and increased oxidant compounds in old mice. However, long-lived mice show similar values to those of adults. In addition, the values of these parameters in adult prematurely aging mice were similar to those in chronologically old animals, and they died before their non-prematurely aging mice counterparts. Thus, the parameters studied are proposed as markers of the rate of aging.

Protective effect of the hydroalcoholic extract of Tripodanthus acutifolius in hypercholesterolemic Wistar rats

Cardiovascular disease (CVD) are a major public health problem, as they are among the leading causes of mortality worldwide. Tripodanthus acutifolius (TA) is a hemiparasite plant used for medicinal purposes with great antioxidant capacity. However, little is known about its hypolipemic effect. Thus, the aim of this study was to evaluate the effects of the hydroalcoholic extract of Tripodanthus acutifolius leaves in hypercholesterolemic Wistar rats. The animals were divided into: (1) NC (Normocaloric Control); (2) HC (Hypercaloric Control); (3) Oral Simvastatin Suspension 10mg/kg (SIM); (4) TA extract 50mg/kg (TA 50mg/kg) and (5) TA 100mg/kg. The in vitro antioxidant activity assay demonstrated that TA shows high antioxidant capacity. The in vivo findings demonstrated that TA supplementation resulted in significant decreases (p<0.05) in Total Cholesterol (TC), Triglycerides (TG) and Low density lipoprotein (LDL) levels, whereas High density lipoprotein (HDL) levels increased significantly in all TA-supplemented groups in relation to the HC group. Hepatic, renal and cardiac function markers improved during supplementation. Serum adiponectin levels increased significantly, whereas C-reactive protein (PCRus) levels decreased in the TA-supplemented in relation to the HC group. Catalase (CAT), superoxide dismutase (SOD) and gluthatione peroxidase (GPx) activities, as well as polyphenols, vitamin C (VitC) and total gluthatione (GSH), increased significantly in the TA-supplemented groups treated when compared to the HC group. Concerning oxidative damage to biomolecules, TA showed a protective effect on lipids, proteins and DNA. Regarding the histological analysis of the aortic artery, TA treatment was able to decrease aortic vasculature. Therefore, TA is rich in antioxidant compounds and may be an alternative for the treatment of hypercholesterolemia.