Changes In Superoxide Dismutase Research Articles

Evaluation of the Post-Mortem Superoxide Dismutase, Glutathione Peroxidase Activities and Malondialdehyde Level in Renal and Brain Tissues: Is it Possible to Estimate Post-Mortem Interval Using these Parameters?

Estimation of the postmortem interval (PMI) is one major area of interest in forensic medicine. We investigated changes of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities and malondialdehyde (MDA) levels in rat brain and renal tissues in the PMI and examined the potential changes which may be useful for an estimation of time of death. Forty albino female rats were used in this study. The rats were sacrificed and divided into five groups: Group 1: 0 hour, Group 2: 6 hours, Group 3: 12 hours, Group 4: 24 hours, and Group 5: 48 hours. The rats were housed at room temperature (22 degrees C ± 2 degrees C) for the defined period for each group, and their brains and kidneys were excised. The postmortem MDA levels were significantly different between groups for both renal and brain tissues (p = 0.003; p = 0.007). The diagnostic adequacy of MDA was calculated. Regarding SOD and GSH-Px, we were not able to obtain any date that would be useful for the prediction of PMI. According to this study, it is possible that an estimation of the PMI can be made using postmortem MDA levels. Regarding SOD and GSH-Px, we were not able to obtain any data that would be useful for the prediction of PMI.

English

The present study investigates and examines the comparative effects of plant extracts such as, garlic, ginger and onion on some organs (liver, kidney and heart) of x-ray exposed rats, using and assaying some biochemical enzymes. Twenty (20) albino rats with an average weight of (155.00 ± 2.01 g), divided into five groups were used for the study. The rats with exception of the control were exposed to x-ray with ionizing radiation at a dose of 525 kv/s. The results indicate some toxicity conferred on the rats were reversed when fed with diet containing garlic, ginger and onion, as evidently shown in some of the biochemical parameters examined that includes: body weight gain, plasma and femur alanine aminotransferase (ALP) activity; enzymatic changes in super oxide dismutase (SOD), catalase (CAT) level in the liver, kidney and heart. Feeding with ginger, garlic and onions extracts failed to restore the x-ray induced inhibition of aldenylate oxidase (AO) and sulphite oxidase (SO) activities in the liver and heart. Data of the study indicates that garlic and onions had more beneficial effects on radiation induced toxicity in rats, as increased body weight gain (P<0.05) of rats caused by radiation which was reduced by feeding with garlic and onion by -65.11 and -30.02%, respectively as against radiation exposed rats fed ginger (-3.17%) compared to rats treated with only x-ray. Together, the results obtained from this study suggest that garlic, ginger and onion may have significant anti-radiation properties, bearing the reversal and restoration observed after radiation exposure on some of the investigated biochemical parameters. Such properties properly harnessed will be helpful in combating cellular oxidative stress. Key words: Radiation, x-ray, ionizing, radical scavengers, anti-oxidant, medicinal plants.

Thiobarbituric acid reactive substances (TBARS) is a state biomarker of oxidative stress in bipolar patients in a manic phase

ObjectivesOxidative stress may contribute to the pathophysiology of bipolar disorder. The aim of this study was to investigate the serum levels or activities of oxidative stress markers in bipolar patients in a manic phase, and evaluate the changes in superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), thiobarbituric acid reactive substances (TBARS), protein carbonyl content (PCC) and 8-hydroxy 2′-deoxyguanosine after treatment (8-OHdG). MethodsWe consecutively enrolled 23 bipolar inpatients in a manic phase and 40 healthy subjects. Serum oxidative stress markers were measured with assay kits. All patients were evaluated by examining the correlation between oxidative stress markers and Young Mania Rating Scale (YMRS) scores. ResultsThe serum TBARS levels in bipolar patients in a manic phase were significantly higher than those of healthy subjects (p=0.006), and serum GPx activity was significant lower than that of healthy subjects (p<0.05). The YMRS scores had a significantly positive association with CAT activity and PCC levels (p<0.05) and a negative association with GPx activity (p<0.05). Twenty bipolar patients were followed up, and their oxidative stress markers were measured at the end of treatment. We found significantly decreased changes in TBARS levels only in bipolar manic patients after treatment (p=0.019). LimitationOur sample size was limited. ConclusionOur results suggest that serum TBARS levels might be a state biomarker of oxidative stress in bipolar patients in a manic phase and after treatment. In addition, GPx deficit might be a trait biomarker of severity of mania.

Cu/ZnSOD involved in tolerance to dehydration in cut rose (Rosa hybrida)

Dehydration results in abnormal flower opening and quality loss during the marketing of cut rose flowers. Our previous studies have revealed that changes in superoxide dismutase (SOD) activity are related to the dehydration tolerance of cut roses. Here, we demonstrate that cut roses were adversely influenced by dehydration conditions, which affected the normal flower opening process, suppressing the increase in flower diameter and shortening vase life. Pretreatment with sodium diethyldithiocarbamate (DDTC), an inhibitor of Cu/ZnSOD activity, accelerated the adverse effects of dehydration on flower opening quality. Compared to flowers placed in water continuously, in dehydrated flowers superoxide anion (SOA) production and SOD activities were enhanced during dehydration and decreased during subsequent rehydration. DDTC pretreatment diminished SOA production and inhibited Cu/ZnSOD activities during both dehydration and subsequent rehydration. Five SOD genes, RhMnSOD1, RhCu/ZnSOD1, RhCu/ZnSOD2, RhCu/ZnSOD3 and RhFeSOD1, were isolated and their expression was analyzed in petals. Dehydration reduced the expression of RhMnSOD1 and RhCu/ZnSOD1/2/3 genes; during rehydration, expression levels recovered. DDTC pretreatment delayed the reduction and recovery of gene expression during dehydration and rehydration, respectively. In conclusion, our results suggest that SOD enzymes, especially Cu/ZnSODs, are involved in the dehydration tolerance of cut rose flowers and that the inhibition of Cu/ZnSOD activities may increase the expression of RhCu/ZnSOD genes in cut rose flower petals via a negative feedback mechanism.

Improvement of superoxide dismutase and catalase in streptozotocin–nicotinamide-induced type 2-diabetes in mice by berberine and glibenclamide

Context: Diabetes mellitus (DM) type 2 is a chronic disease characterized by hyperglycemia and insulin resistance. Oxidative stress participates in development and progression of DM, in which changes of superoxide dismutase (SOD) and catalase (CAT) were noted in DM mice. Berberine has been widely used as an alternative medicine and proved to be effective for the treatment of DM and dyslipidemia.Objective: Impacts of berberine on transcriptional regulation of SOD and CAT and their enzyme activities, including the level of malondialdehyde (MDA) formation, were examined in the DM type 2-induced mice to clarify its antioxidation potential, compared with a common hypoglycemic drug, glibenclamide.Materials and methods: Noninsulin-dependent diabetes was induced in mice by a single intraperitoneal streptozotocin–nicotinamide injection. Diabetic mice were treated daily with glibenclamide (10 mg/kg/d) and/or berberine (100 mg/kg/d) for 2 weeks. The fasting blood glucose and the MDA levels in the mouse liver, brain and kidneys were monitored using Glucometer® (Accu-Check® Advantage II Performa kits, Roche Diagnostics, Germany) and thiobarbituric acid substance assay, respectively. The expression of SOD and CAT mRNA were determined in the mouse liver and the activities of SOD and CAT enzymes were determined in mouse liver, brain and kidneys, respectively.Results: Berberine exhibited similar hypoglycemic potential as glibenclamide to lower area under the curve of the fasting blood glucose. In DM type 2 mice, berberine increased the hepatic CuZn-SOD mRNA expression and the kidney SOD and CAT activities to normal levels. Moreover, DM-induced lipid peroxidation by increasing of MDA levels in both the liver and brain and lipid peroxidation status was restored by berberine.Conclusion: Berberine possessed hypoglycemic properties and strong potential to improve the oxidant–antioxidant balance, though the combination treatment of berberine and glibenclamide did not show additional benefit over the treatment with berberine alone.

Effect of hypoglycemic anti-deafness capsules in diabetic patients with deafness and toxicological assessment in rats

ObjectiveThrough experiment on animals and clinical trials to explore the safety and efficacy of hypoglycemic anti-deafness capsules on diabetic patients with deafness. MethodsTotal 296 patients with non-insulin dependent diabetes mellitus (NIDDM) were randomly divided into two groups. A treatment group of 164 patients (208 ears) was treated with hypoglycemic anti-deafness capsules based on TCM syndrome differentiation. A control group of 132 patients (184 ears) was treated with glibenclamide and conventional drug treatment for deafness. The following were observed: hearing, fasting plasma glucose (FPG), 2 h postprandial plasma glucose (2hPG), 24 h urine glucose (24hUG), improvement of main symptoms, platelet function, and changes in superoxide dismutase (SOD) and lipid peroxide (LPO) levels. In animal studies, Kunming mice, weighing 18-22 g were used. Half of the mice were males and half were females. Wistar rats, weighing 80-120 g were used. Half of the rats were males and half were females. Male Wistar rats, weighing 200-220 g, were also used. Their acute and chronic toxicity was studied. ResultsThe hearing improvement was 56.7% in the treatment group and 26.6% in the control group. FPG, 2hPG, and 24hUG were improved significantly (P<0.05, P<0.01, P<0.01, respectively) in the treatment group and 2hPG and 24hUG improved significantly in the control group (P<0.05, P<0.05). The improvement in 2hPG and 24hUG in the treatment group was significantly greater than that in the control group P<0.01). There was no significant difference in FPG between the two groups (P<0.05). Main symptoms in the treatment group were significantly more improved than those in the control group (P<0.05, P<0.01). In the treatment group, platelet adhesion and aggregation, SOD, and LPO were all significantly improved from before treatment (P<0.05, P<0.01). However, in the control group, except LOP (P<0.05), there were no significant differences from before treatment to after (P<0.05). In animal studies, no obvious acute or long-term toxicity was observed from capsule administration. ConclusionThrough experiment on animals and clinical trials, we can found that hypoglycemic anti-deafness capsules could decrease blood glucose and serum triglycerides of alloxan-induced diabetic rats. This herbal capsule is effective for safely treating diabetic patients with deafness.

Dual effects of molybdenum on mouse oocyte quality and ovarian oxidative stress

A sub-acute toxicity test was performed to investigate the effects of molybdenum (Mo) on ovarian function. ICR adult female mice were exposed to Mo by free access to distilled water containing the Mo at 5, 10, 20, and 40 mg/L for 14 days. Compared to the control group, M II oocyte morphology, ovary index, and ovulation improved within the 5 mg/L Mo group, but were negatively affected by Mo at 40 mg/L. Morphologically abnormal ovarian mitochondria were observed at ≥ 20 mg/L. These alterations accompanied the changes in superoxide dismutase (SOD), glutathione peroxidise (GPx), and malondialdehyde (MDA) levels in ovaries. In conclusion, Mo affects oocyte quality possibly through regulating ovarian oxidative stress in a dose-dependent manner. It appears that Mo may improve ovarian function at a suitable concentration, which might be a candidate for the treatment of female infertility.

Suppression of nuclear factor erythroid 2-related factor 2 via extracellular signal-regulated kinase contributes to bleomycin-induced oxidative stress and fibrogenesis

Pulmonary fibrosis is a serious and irreversible lung injury with obscure etiologic mechanisms and no effective treatment to date. This study explored a crucial link between oxidative stress and pulmonary fibrogenesis, focusing on nuclear factor erythroid 2-related factor 2 (Nrf2), a core transcription factor in antioxidative regulation systems. Treatment of C57 BL/6 mice with bleomycin increased fibroblast viability and collagen production and significantly downregulated Nrf2. In addition, prominent oxidative stress was indicated by changes in superoxide dismutase, catalase activity, and glutathione and thiobarbituric acid-reactive substance levels. In a cell-based model, bleomycin suppressed Nrf2 activation via extracellular signal-related kinase phosphorylation, enhancing intracellular reactive oxygen species in lung fibroblasts and stimulating abnormal cell proliferation and collagen secretion. To confirm this novel mechanism of bleomycin-induced fibrogenesis, we attempted to upregulate Nrf2 and related antioxidant proteins in bleomycin-treated fibroblasts using a putative Nrf2 activator, caffeic acid phenethyl ester, and the results showed that bleomycin-induced fibroblast proliferation and collagen content were attenuated through improved redox balance. Collectively, these results disclose a potential regulatory mechanism in pulmonary fibrosis that will aid the development of new therapies.

Effect of Drought Stress on Superoxide Dismutase Activity in Two Species of Haloxylon aphyllum and Haloxylon persicum

Superoxide dismutase activity changes were studied at different periodic tensions using of spectrophotometric measurement of decline in NitroBlue Tetrazolium reduction to Blue Formazan at 560 nm in Haloxylon aphyllum and Haloxylon persicum. The aim of this study was to investigate the changes of superoxide dismutase in applied drought stress in two species of Haloxylon. The results showed that the effect of drought stress on increase in superoxide dismutase activity was significant (p < 0.01) in two haloxylon species. Drought increased enzyme activity at severe tensions. When two haloxylon species were placed under 7 and 14 days no-watering treatments (mild tensions), the enzyme activity was more than its activity in control treatment and less than one in 21 and 28 days no-watering treatments (severe tensions). The enzyme activity in branchlets of Haloxylon aphyllum under 21 and 28 days no-watering treatments was 20.2 and 29.5% more than its activity under control treatment respectively. This activity in Haloxylon persicum was 21.6 and 31.4% more than its activity under control treatment, respectively. With the advent of drought, superoxide dismutase activity increased in two species of haloxylon. The increasing of superoxide dismutase activity in time of dryness advent in Haloxylon aphyllum was more than Haloxylon persicum, which can be raised as an acceptable factor and vindicator in being more resistant of Haloxylon aphyllum to environmental drought.

Changes in oxidative stress markers in patients with schizophrenia: The effect of antipsychotic drugs

The aim of this study was to investigate the serum levels or activities of oxidative stress markers in patients with schizophrenia in acute phase and evaluate the changes in superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione (GSH) and thiobarbituric acid-reactive substances (TBARS) after treatment. We consecutively enrolled 41 patients with schizophrenia in acute phase, and 27 patients were followed up with a 4-week antipsychotic treatment. Serum oxidative stress markers were measured with assay kits. We found that Positive and Negative Syndrome Scale (PANSS) total scores were significantly negatively correlated with serum GPx activity and GSH levels and positively correlated with serum SOD activity in patients with schizophrenia in acute phase. In addition, serum GPx activity had a positive correlation with GSH levels and negative correlation with SOD activity. We also found that serum SOD activity was significantly negatively correlated with TBARS levels in patients in acute phase. Furthermore, we found significantly increased changes only in GPx activity in female patients receiving the 4-week treatment (P=0.006). In conclusion, our results suggest that SOD, GPX and GSH might be indicators of schizophrenia severity in acute phase. Furthermore, antipsychotic drugs might affect serum GPx activity in female patients receiving the 4-week treatment.

Evaluating d-methionine dose to attenuate oxidative stress-mediated hearing loss following overexposure to noise

Noise exposure causes an excessive reactive oxygen species (ROS) generation as an unwanted byproduct of high metabolic activity. Oxidative stress and antioxidative protective mechanisms have been therefore proposed as the most interesting issues in the development of noise-induced hearing loss. The aim of this study was to examine changes in superoxide dismutase (SOD), catalase (CAT) and the auditory brainstem response (ABR) in the cochlea of C57BL/6 mice 1, 7 and 14 days after exposure to 4 kHz octave band noise at the intensity of 110 dB SPL for 8 h. The evaluation of three d-methionine (d-met) doses (100, 200 and 400 mg/kg) has been performed in order to choose an optimal concentration displaying most effectively its antioxidant and thereby otoprotective functions. Administering d-met at the dose of 400 mg/kg resulted in a significant decrease in threshold shift (TS) independently of the evaluation time after exposure to noise. SOD activity was strongly supported by the same concentration (400 mg/kg) of d-met. This effect was seen not shortly, but 7 and 14 days after exposure to noise. CAT activity was induced only by noise and it reached the peak levels 7 days after exposure. d-Met at the doses of 200 and 400 mg/kg significantly decreased noise-induced changes in CAT activity. The findings of this study indicate that the protective effect depends on the concentration of d-met and can be fully expressed only when the drug is administered in the dose 400 mg/kg.

Melatonin reduces X-ray radiation-induced lung injury in mice by modulating oxidative stress and cytokine expression

Purpose: The modification of radiation-induced lung injuries by melatonin was studied by measuring changes in oxidative stress, cytokine expression and histopathology in the lung tissue of mice following irradiation.Materials and methods: The thoraces of C57BL/6 mice were exposed to a single X-ray radiation dose of 12 Gy with or without 200 mg/kg of melatonin pretreatment. The level and localization of transforming growth factor (TGF)-β1 protein were measured using an enzyme-linked immunosorbent assay (ELISA) method and immunohistochemical staining, respectively. Real-time quantitative polymerase chain reaction (PCR) was established to evaluate the relative mRNA expression levels of TGF-β1, tumor necrosis factor (TNF)-α, interleukin (IL)-1β and IL-6.Results: Malondialdehyde (MDA) levels increased after irradiation and then significantly reduced (1.9-fold) under melatonin treatment. Changes in superoxide dismutase (SOD) and catalase activities, as well as glutathione (GSH) levels, after irradiation were significantly reduced by melatonin, including a notable 5.4-fold difference in catalase activity. We observed increased expression of TGF-β1 and TNF-α after irradiation and a significant reduction in the elevation of their expression by melatonin treatment. Furthermore, irradiation-induced histopathologic alterations were obviously abated in the melatonin-pretreated mice.Conclusions: The present results suggest that melatonin reduces radiation-induced lung injury via a significant reduction of oxidative stress and of the production of cytokines, such as TGF-β1 and TNF-α, the production of which increased following lung irradiation.

Proteomic analysis of boar spermatozoa and quantity changes of superoxide dismutase 1, glutathione peroxidase, and peroxiredoxin 5 during epididymal maturation

Mammalian spermatozoa and their various proteins undergo various modifications during maturation in the epididymis. To characterize proteins that change in quantity during this maturational process, boar spermatozoa were collected from various regions of the epididymis, and extracts were analyzed by two-dimensional gel electrophoresis (2-DE). A number of proteins were identified as changing in quantity, and MALDI-MS analysis revealed that superoxide dismutase 1 (SOD1) from the acrosomal proteins of spermatozoa, and glutathione peroxidase (GPX) and peroxiredoxin 5 from the membranous fraction increased during the epididymal transit of spermatozoa. These proteins are antioxidants that remove reactive oxygen species (ROS); they are presumed to protect spermatozoa during epididymal transit and storage. Western blot analysis of SOD1, GPX and peroxiredoxin 5 showed that these protein levels increased as the spermatozoa traveled from the caput to the cauda epididymis. Activity analysis showed that total SOD activity also increased. Therefore, we conclude that several antioxidant proteins increase during the transit of boar spermatozoa through the epididymis, ultimately contributing to the maturation and/or survival of sperm.

Role of hydrogen peroxide and antioxidative enzymes in Pinus tabulaeformis seedlings inoculated with Amanita vaginata and/or Rhizoctonia solani

The ectomycorrhizal fungus Amanita vaginata can control damping off (Rhizoctonia solani) and promote growth of Pinus tabulaeformis seedlings. The aim of this study was to investigate whether reactive oxygen species and antioxidative enzymes play a role in preventing damping off in ectomycorrhizal roots. Two months after P. tabulaeformis roots were inoculated with A. vaginata, the roots were inoculated with R. solani. During the early stages (2–96 h) of R. solani infection, the quantity and localisation of hydrogen peroxide and the activities of superoxide dismutase and catalase were evaluated. A burst of hydrogen peroxide occurred in ectomycorrhizal roots and in non-ectomycorrhizal roots when attacked by R. solani. In ectomycorrhizal roots, hydrogen peroxide production peaked 12 h after R. solani inoculation, which coincided with an increase in the activity of superoxide dismutase and catalase, whereas in non-ectomycorrhizal roots, hydrogen peroxide production peaked 24 h after R. solani inoculation and did not coincide with changes in superoxide dismutase or catalase activity. The imbalanced activities of superoxide dismutase and catalase might cause excessive accumulation of hydrogen peroxide and consequent damage to cell walls. Electron microscopy revealed that there was a positive correlation between hydrogen peroxide levels and the number of amyloplasts, with seedlings inoculated with A. vaginata and/or R. solani showing higher levels. These results indicated that A. vaginata inoculation enhanced damping off resistance and stimulated seedling growth, which may be due to the activation of a burst of hydrogen peroxide and its scavenging enzymes and the production of biochemical substances such as amyloplasts.

Response of Reed Canary Grass to Salt Stress during Seed Germination and Vegetative Stage

The aim of this experiment was to determine the responses of reed canary grass (Phalaris arundinacea L.) to salt stress during germination and vegetative growth. Therefore, effects of salinity (0, 50, 100,150, 200,250mMNaCl) on germination, changes in the percentage of germination, abnormal seedling and un-germinated seeds of two germplasms (Zxy06p-2449 and Zxy06p-2653) during germination under stress were determined. Moreover, during vegetative growth(40d old plants), changes in superoxide dismutase(SOD), peroxidase(POD), catalase (CAT), electrolyte leakage were also investigated after salt treatment for 5,10 and 15d. Salt stress decreased the germination percentage. Few seeds germinated at 200mMNaCl, abnormal seedlings and un-germinated seeds increased significantly under the higher salt concentration. During vegetative growth, increased activities of SOD, in 50,100 and 150mMNaCl treated-plants may help to avoid oxidative damage. Differential responses of antioxidant enzymes to salt stress during germination and vegetative growth suggested different antioxidant metabolism in reed canary grass. From the results obtained in present study, it can be suggested that reed canary grass is a moderately salt-tolerant specie with considerable germplasm differences. Zxy06p-2449 and Zxy06p-2653 will not be survive in long-term (&gt;15d) salt treatment under 150mMNaCl, especially Zxy06p-2653 which shown more sensitive under higher salt concentrations

Temporal and regional changes of superoxide dismutase and glutathione peroxidase activities in rats exposed to focal cerebral ischemia

Reactive oxygen species are important cause of tissue injury during cerebral ischemia and reperfusion (I/R). Superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) are intracellular enzymes responsible for endogenous antioxidant defense of tissues affected by I/R. The aim of this study was to examine temporal and regional changes of SOD and GSH-Px activities in animals exposed to transient focal cerebral ischemia. Male Wistar Hannover rats were subjected to the right middle cerebral artery occlusion for 2 h. The animals were sacrificed immediately, 0·5, 1, 2, 3, 6, 24, 48, 72 or 168 h after ischemic procedure. SOD and GSH-Px activities were determined spectrophotometrically in the hippocampus and parietal cortex, both unilaterally and contralaterally to the occlusion. Sham-operated animals were used as the control group. Our results indicated that transient focal cerebral ischemia causes significant changes in SOD activities in the hippocampus and parietal cortex such as in GSH-Px activities in the parietal cortex, unilaterally and contralaterally to the lesion in rats during different reperfusion periods. Statistically significant activation of GSH-Px was registered neither in the right nor in the left hippocampus of ischemic animals.

Effects of the Consumption of Caffeinated and Decaffeinated Instant Coffee Beverages on Oxidative Stress Induced by Strenuous Exercise in Rats

Many authors attribute the antioxidant activity of brewed coffee to its caffeine content. In addition, caffeine intake has been associated with increased performance during physical exercise. This study analyzed the in vivo effects of drinking caffeinated and decaffeinated instant coffee (8%, w/v) on oxidative stress and antioxidant enzyme activity in the anterior tibialis muscles of rats subjected to intense exercise. It was observed that exercise induced lipid peroxidation (estimated using malondialdehyde) and protein oxidation (evaluated by determining the formation of carbonyl groups) in the muscle (P < 0.05). Decaffeinated instant coffee and caffeine solution did not exhibit antioxidant activity in vivo. Caffeinated instant coffee beverage intake did not induce changes in superoxide dismutase and glutathione peroxidase activities but was able to diminish lipid and protein oxidation in the anterior tibialis muscles of rats after exercise (P < 0.05), contributing to a reduction in the oxidative stress triggered by exercise.

Methyl deficient diet aggravates experimental colitis in rats

Inflammatory bowel diseases (IBD) result from complex interactions between environmental and genetic factors. Low blood levels of vitamin B12 and folate and genetic variants of related target enzymes are associated with IBD risk, in population studies. To investigate the underlying mechanisms, we evaluated the effects of a methyl-deficient diet (MDD, folate, vitamin B12 and choline) in an experimental model of colitis induced by dextran sodium sulphate (DSS), in rat pups from dams subjected to the MDD during gestation and lactation. Four groups were considered (n= 12–16 per group): C DSS− (control/DSS−), D DSS− (deficient/DSS−), C DSS+ (control/DSS+) and D DSS+ (deficient/DSS+). Changes in apoptosis, oxidant stress and pro-inflammatory pathways were studied within colonic mucosa. In rat pups, the MDD produced a decreased plasma concentration of vitamin B12 and folate and an increased homocysteine (7.8 ± 0.9 versus 22.6 ± 1.2 μmol/l, P < 0.001). The DSS-induced colitis was dramatically more severe in the D DSS+ group compared with each other group, with no change in superoxide dismutase and glutathione peroxidase activity, but decreased expression of caspase-3 and Bax, and increased Bcl-2 levels. The mRNA levels of tumour necrosis factor (TNF)-α and protein levels of p38, cytosolic phospolipase A2 and cyclooxygenase 2 were significantly increased in the D DSS+ pups and were accompanied by a decrease in the protein level of tissue inhibitor of metalloproteinases (TIMP)3, a negative regulator of TNF-α. MDD may cause an overexpression of pro-inflammatory pathways, indicating an aggravating effect of folate and/or vitamin B12 deficiency in experimental IBD. These findings suggest paying attention to vitamin B12 and folate deficits, frequently reported in IBD patients.

Tea polyphenols alleviate oxidant injury following CPR in an asphyxia rat model

BackgroundCerebral ischemia/reperfusion injury following cardiac arrest and cardiopulmonary resuscitation (CPR) have been demonstrated. Oxidant injury plays a critical role in the process. We have reported that tea polyphenols from green...

Epigenetic regulation of pulmonary arterial hypertension

Pulmonary arterial hypertension (PAH) is diagnosed as a sustained elevation of pulmonary arterial pressure to more than 25 mm Hg at rest or to more than 30 mm Hg with exercise. PAH is an intrinsic disease of the pulmonary vascular smooth muscle and endothelial cells in association with plexiform lesions, medial thickening, concentric laminar intimal fibrosis and thrombotic lesions. Pulmonary vascular remodeling is the characteristic pathological change of PAH. The pathogenesis of PAH has been studied at the level of smooth muscle and endothelial cells. Existing research does not adequately explain susceptibility to the disease, and recent evidence reveals that epigenetic alterations may be involved in PAH. Epigenetics refers to all heritable changes in phenotype or in gene expression states, including chromatin remodeling, DNA methylation, histone modification and RNA interference, which are not involved in the DNA sequence itself. This review will focus on recent advances in epigenetics related to PAH, including epigenetic changes of superoxide dismutase, endothelial nitric oxide synthase and the bone morphogenetic protein signaling pathway. This will provide new insight for improved treatment and prevention of PAH. Future work aimed at specific epigenetic treatments may prove to be an effective therapy for patients with PAH.