Measurement Of Malondialdehyde Research Articles

Evaluation of Oxidative Stress Levels and Antioxidant Enzyme Activities in Burst Fractures

BackgroundSpinal burst fractures are pathologies that occur in spinal injuries and cause significant mortality and morbidity as a result. Burst fractures in spinal cord injuries can result in rapid and significant oxidative stress. In addition to the primary injury in severe spinal cord injuries, subsequent secondary lesions are mainly due to inflammatory cascade activation and excessive production of free radicals. This study evaluated oxidative stress and antioxidant enzyme levels in burst fractures.Material/MethodsTwenty patients with burst fractures were diagnosed and underwent surgery and 20 healthy control subjects were included in the study. Neurological status was evaluated using the American Spine Injury Association Impairment Scale (ASIA) before and after surgery. Neurological function was scored as ASIA A: complete deficits, ASIA B–D: incomplete deficits, and ASIA E: neurologically intact. Spectrophotometry was performed to measure malondialdehyde (MDA) and low glutathione (GSH), glutathione peroxidase (GPx) levels, which represent lipid peroxide content. Evaluations were performed within 2 days after injury in the patients.ResultsMDA levels were higher in the burst fracture group (p<0.001), whereas GSH and SOD activities were higher in the control group (both p<0.001). There was no statistically significant difference in GPx levels between the groups (p=0.482).ConclusionsOxidative stress appears to be related to burst fractures. Considering the importance of burst fractures in spinal cord injuries, a better understanding of these mechanisms may help in defining the role of oxidative stress after burst fractures. Prospective, randomized, controlled trials may reveal new therapeutic approaches that include antioxidants for explosive fractures focusing on oxidative stress.

The effect of ellagic acid on photodynamic therapy in leukemia cells.

Ellagic acid (EA) is a naturally phenolic acid presented in different foods. It has a variety of biological activities including antioxidant, anti-inflammatory, anti-microbiological and anti-cancer properties. On account of its antioxidant activity, EA might protect cancer cells from free radical damage in photodynamic therapy (PDT) during which reactive oxygen species (ROS) production was stimulated leading to irreversible tumor cell injury. In this study, the influence of EA on K562 cells in 5-aminolevulinic acid (ALA)-based PDT is demonstrated. Cell apoptosis was assayed by flow cytometry. Oxidative damage induced by PDT was investigated by measurement of malondialdehyde (MDA). Comet assay was used to evaluate the potential genotoxic effect induced by PDT on the cells. The results showed that EA supplementation alone did not affect the lipid peroxidation, DNA damage and apoptosis in K562 cells. It increases the lipid peroxidation, DNA damage, apoptosis and decreases the survival rate in K562 cells induced by ALA-PDT. The singlet oxygen quencher sodium azide suppresses apoptosis, lipid peroxidation and DNA damage induced by EA in PDT. In conclusion, EA consumption during PDT did not decrease the effectiveness of cancer therapy on malignant cells. The effect of antioxidants on PDT maybe was determined by its sensitization ability to singlet oxygen.

Ethyl pyruvate prevents from chronic cerebral hypoperfusion via preserving cognitive function and decreasing oxidative stress, caspase 3 activation and IL-1β level.

One of the important risk factors for dementia is chronic cerebral hypoperfusion (CCH) especially in patients with cerebrovascular disease. In the present study, using rat model of bilateral common carotid artery occlusion, the possible protective effects of ethyl pyruvate (EP) have been explored in terms of memory impairment, oxidative stress, and levels of caspase-3, Na-K ATPase, and IL- 1β. Rats were treated with EP (50 mg/kg, i.p) for 4 weeks. Cognitive function was evaluated by Morris Water Maze (MWM). Both levels of caspase-3 and Na-K ATPase in tissue, IL-1β in plasma were measured by ELISA method. Status of oxidative stress in brain was assessed by the measurements of the tissue malondialdehyde (MDA) and reduced glutathione (GSH) contents. RESULTS: Results showed that CCH caused a striking impairment of spatial working memory, accompanied with increased levels of MDA and IL-1β as well as caspase 3 level. The treatment with EP, however, significantly improved the memory impairment. Moreover, the treatment also provided beneficial effects on the disturbances of caspase 3, IL-1β and MDA. This study strongly imply that the EP administration can alleviate the memory impairment observed due to CCH. The protection provided by EP may result from inhibition of inflammatory response, apoptotic processes and oxidative stress (Fig. 3, Ref. 58).

AMPK Hyper-Activation Alters Fatty Acids Metabolism and Impairs Invasiveness of Trophoblasts in Preeclampsia

Background/Aims: Preeclampsia (PE) has long been assumed to be an ischemic disease of the placenta, although there is limited evidence as to how the ischemia impacts on the placenta. AMP-activated protein kinase (AMPK) is a key regulator of cellular energy metabolism and plays an important role in a variety of ischemic diseases by enhancing energy production. The present study investigated placental metabolism in PE, and the role of AMPK in regulating trophoblast function. Methods: placentas from normal and PE complicated pregnancies were subjected to GC-MS to identify fatty acids (FA) metabolic fingerprints, and total FA oxidation was assessed by malondialdehyde (MDA) measurement. The AMPK-ACC signaling pathway was assessed by q-PCR and Western Blotting. HTR8/SVneo trophoblast cultures were exposed to different oxygenation conditions to establish an in vitro PE cell model; further analysis by GC-MS for metabolite profiling was then undertaken. Trophoblasts invasion was assessed by a matrigel transwell assay in the presence/absence of AMPK expression and after manipulations of AMPK activity, and then further validated by human villi outgrowth experiments. Results: AMPK phosphorylation and MDA production were significantly elevated in placentas from pregnancies complicated by PE. Metabolism of cis double bond FA was inhibited while trans double bond FA metabolism was promoted in PE placentas. HTR8/SVneo cell culture conditions of persistent low oxygenation mimicked the hyper-activation of AMPK and enhanced the FA oxidation that was observed in PE. AMPK activation impaired trophoblast invasion, while AMPK inhibition promoted trophoblast invasion. Conclusion: PE complicated placentas are associated with AMPK hyper-activation and consequent alterations in FA oxidation, which inhibit trophoblast invasion.

THE BIOCHEMICAL ALTERATION AND DNA DAMAGE IN RATS (RATTUS RATTUS) AFTER CHRONIC INTRAPERITONEALLY INJECTION TO PURIFIED MICROCYSTIN-LR FROM ANABAENA CIRCINALIS

Objective: This study determined the effect of purified microcystin-leucine arginine (MC-LR) on biochemical and DNA damage parameters in rats.Methods: Utilization of preparative high-performance liquid chromatography in analysis, purification and collection of MC-LR, then intraperitoneally injection of purified MC-LR to rats. At the end of exposure, animals were sacrificed, and liver cell was isolated to measure the biochemical markers such as superoxide dismutase (SOD), catalase (CAT) and glutathione (GSH) as well as measured malondialdehyde (MDA), reactive oxygen species (ROS) and cytochrome P450 (Cyt P450), and DNA damage markers such as comet length, tail length, and tail moment were measured with the single cell gel electrophoresis also called comet assay.Results: The present results showed significantly increased activities of SOD as well as concentration of MDA, ROS with increasing concentration of MC-LR but the activities of CAT and GSH, as well as Cyt P450, were significantly decreased with increasing MC-LR dose while makers of DNA damage such as comet length, tail length, and tail moment also significantly increased with increasing MC-LR dose.Conclusion: This study demonstrated that chronic exposure to MC-LR toxin can induce alteration of biochemical and DNA damage markers.

Resveratrol Attenuates the Cytotoxicity Induced by Amyloid-β1-42 in PC12 Cells by Upregulating Heme Oxygenase-1 via the PI3K/Akt/Nrf2 Pathway.

Oxidative stress and cytotoxic damage induced by amyloid beta (Aβ) have been considered pivotal in the pathogenesis of Alzheimer's disease (AD) and may represent a target for treatment. The phosphatidylinositol 3-kinase (PI3K)/Akt pathway elicits a survival signal to protect against multiple injuries, and the transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2), a downstream target of the PI3K/Akt pathway, can bind to HO-1. Resveratrol, a natural polyphenol derived from grapes, has been widely reported to have diverse antioxidative effects against AD, but the mechanisms have not been fully elucidated. The present study aims to investigate the effects of resveratrol on Aβ1-42-induced cytotoxicity in PC12 cells and to explore the potential mechanisms of these effects. PC12 cells were cultured and treated with Aβ1-42. Oxidative stress was assessed by measuring malondialdehyde (MDA), glutathione (GSH), and superoxide dismutase (SOD) levels. After treating with resveratrol at different concentrations (0, 10, 20, 40μM) and for different durations (24, 48, 72h), the generation of MDA, GSH, and SOD were detected; cell viability was assessed by MTT assay. The production of reactive oxygen species (ROS) was determined using an ROS Assay Kit. Western blotting was used to detect the protein expression. Our studies showed that pretreatment with resveratrol could reduce Aβ1-42-induced oxidative stress in PC12 cells by inhibiting the generation of MDA and ROS and increasing the production of SOD and GSH. Resveratrol markedly attenuated the Aβ1-42-induced loss in cell viability in PC12 cells in both a dose- and time-dependent manner. More importantly, resveratrol stimulated the activation of HO-1, Nrf2, PI3K, and phosphorylated Akt. Notably, the neuroprotective effects of resveratrol were eliminated by the HO-1 inhibitor zinc protoporphyrin IX (ZnPP), Nrf2 small interfering RNA (siRNA), and the PI3K/Akt inhibitor LY294002. Taken together, the findings suggest that the cytoprotection of resveratrol against the cytotoxicity induced by Aβ1-42 in PC12 cells is through the upregulation of HO-1 expression via the activation of the PI3K/AKT/Nrf2 intracellular signaling pathway, which might provide novel insights for understanding the mechanism of the neuroprotective effect of resveratrol as an anti-AD drug.

Antioxidant activity of omega-3 derivatives and their delivery via nanocages and nanocones: DFT and experimental in vivo investigation.

The antioxidant properties of omega-3 were investigated via experimental in vivo and theoretical methods. For experimental evaluation, oxidative stress was induced by 30min bilateral renal ischemia and 24h of reperfusion in male Sprague Dawley rats. The oxidative stress was evaluated through measuring malondialdehyde (MDA) and ferric reducing/antioxidant power (FRAP) levels in renal tissue. In theoretical methods, the reaction enthalpies of antioxidant mechanisms of omega-3 were calculated and the effects of NHMe, OMe, OH, Cl, and Me substituents on its antioxidant activity were investigated. Moreover, the omega-3 delivery potential by carbon and boron nitride nanocages and naocones were evaluated. The experimental results showed that omega-3 administration decreases MDA and increases FRAP levels after their changes by ischemia/reperfusion. Theoretical results indicated that NHMe and OMe substituents can significantly improve the antioxidant activity of omega-3. Also, boron nitride nanocone (BNNC) has higher |∆Ead| values, so it has higher potential for omega-3 delivery. Taken together, the new findings presented here indicate that omega-3 has anti-oxidative properties and NHMe and OMe substituents can improve its antioxidant activity. Moreover, adsorption of omega-3 on the surface of the studied nanostructures was exothermic, and BNNC with higher |∆Ead| values has higher potential for omega-3 delivery. Graphical abstract The interaction and adsorption of BNNC with omega-3 is exothermic and experimentally possible from the energetic viewpoint, so the BNNC with higher |∆Ead| and |∆Gad| values has higher potential for omega-3 delivery.

Volumetric changes in the aging rat brain and its impact on cognitive and locomotor functions

Impairments in cognitive and locomotor functions usually occur with advanced age, as do changes in brain volume. This study was conducted to assess changes in brain volume, cognitive and locomotor functions, and oxidative stress levels in middle- to late-aged rats. Forty-four male Sprague-Dawley rats were divided into four groups: 14, 18, 23, and 27months of age. 1H magnetic resonance imaging (MRI) was performed using a 7.0-Tesla MR scanner system. The volumes of the lateral ventricles, medial prefrontal cortex (mPFC), hippocampus, striatum, cerebellum, and whole brain were measured. Open field, object recognition, and Morris water maze tests were conducted to assess cognitive and locomotor functions. Blood was taken for measurements of malondialdehyde (MDA), protein carbonyl content, and antioxidant enzyme activity. The lateral ventricle volumes were larger, whereas the mPFC, hippocampus, and striatum volumes were smaller in 27-month-old rats than in 14-month-old rats. In behavioral tasks, the 27-month-old rats showed less exploratory activity and poorer spatial learning and memory than did the 14-month-old rats. Biochemical measurements likewise showed increased MDA and lower glutathione peroxidase (GPx) activity in the 27-month-old rats. In conclusion, age-related increases in oxidative stress, impairment in cognitive and locomotor functions, and changes in brain volume were observed, with the most marked impairments observed in later age.

Angiotensin II induces calcium-mediated autophagy in podocytes through enhancing reactive oxygen species levels

As well known, abnormalities of Angiotensin II (Ang II) is closely related with glomerular damage. This study was to investigate whether Ang II could affect autophagy in podocytes via oxidative stress, and whether autophagy had a positive role in protecting podocytes impaired by Ang II. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay showed that Ang II induced podocyte death. The measurements of malondialdehyde (MDA) and H2O2 levels, and flow cytometry assay revealed that Ang II considerably increased reactive oxygen species (ROS) generation in podocytes. Meaningfully, treatment with ROS scavenger N-(mercaptopropionyl)-glycine (N-MPG) could inhibit podocyte death and attenuate accumulation of ROS induced by Ang II. The patch-clamp experiments indicated that Ang II increased the current of transient receptor potential canonical 6 (TRPC6). Moreover, measurement of Fluo-3 image showed that Ang II increased intracellular Ca2+ level, as N-MPG and La3+ impeded Ang II induced Ca2+ influx. Acridine orange staining indicated that Ang II induced accumulation of acidic vacuoles. Beclin-1 and LC3 are essential for autophagosome formation. Furthermore, as one of the selective substrates for autophagy, P62 plays a key role in the formation of cytoplasmic proteinaceous inclusion. Western blot assay presented that Ang II obviously elevated LC3-II/LC3-I ratio and expression of beclin-1, and reduced expression of P62. Meanwhile, N-MPG expectedly down-regulated autophagy in Ang II-treated podocytes. Rapamycin can enhance the level of autophagy by inhibiting mTOR, and 3-methyladenine (3-MA) can inhibit autophagosome formation through blocking class III phosphatidylinositol 3-kinase. MTT assay exhibited that rapamycin significantly enhanced the cell viability, while 3-MA considerably reduced it in Ang II-treated podocytes. Consequently, this study demonstrated that Ang II could increase TRPC6 induced Ca2+ influx and enhance autophagy through increasing ROS levels in podocytes, and autophagy could protect Ang II-treated podocytes. Improving TRPC6 channels and autophagy may become a new targeted therapy to relieve glomerular damage induced by Ang II.

THE POTENCY OF ALPHA LIPOIC ACID AS ANTI INFLAMMATORY ON THE COMPLETE FREUND'S ADJUVANT-INDUCED RHEUMATOID ARTHRITIS IN RAT MODEL

Rheumatoid arthritis (RA) is an autoimmune diseases which is characterized by chronic inflammation of the synovial tissue in joints. This research was designed to investigate the effect of alpha lipoic acid as antioxidant on rats with complete freund’s adjuvant (CFA)-induced RA by intra articular injection of complete freund’s adjuvant (CFA). ALA was administered orally once a day for 7 days at 30, 60 and 120 mg doses a week after CFA injection. The severity of arthritis was evaluated by joint diameter and latency time on thermal stimulation. Joint diameter and latency time on thermal stimulation will measured on day 0, 3, 5, 7, 10, 12 and 14. Measurement of malondialdehyde (MDA) level in plasma was performed using thiobarbituric acid (TBA) method to assess lipid peroxidation. Histology of joint was examined by microscope following hematoxylin-eosin staining. The result showed that treatment with ALA at 30 mg and 60 mg significantly decreased the joint diameter compared to CFA group (p=0.003; p=0.001 respectively) and rat’s latency time on thermal stimulation was also significantly increased compared to CFA group (p=0.015; p=0.026 respectively). Measurement of MDA in CFA group and ALA group had no significant difference. Histological staining indicated that the recovery of the synovial membranes of joint in ALA group had no effect. Results indicated that ALA has the effect to suppress the development of inflammation in RA but not through oxidative stress pathway.

Evaluation of Antioxidant Activities and Phenolic Compounds of Scorzonera latifolia (Fisch. & Mey.) DC. Collected from Different Geographic Origins in Turkey.

The chemical composition of plants is considered to be affected by many parameters. Therefore, the region where the samples are collected is likely to have an influence on the composition of phenolic compounds, so that their biological activities. In the present study, evaluation of antioxidant activity potentials of Scorzonera latifolia (Fisch. & Mey.) DC. aerial parts and roots, which were collected from different regions of Turkey, was aimed. 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging method and measurement of malondialdehyde (MDA) levels were used for determining antioxidant capacities of the tested extracts. In order to observe variations in the chemical composition of the investigated samples qualitatively as well as quantitatively, high performance liquid chromatography analyses were performed. Quantitative analysis showed that the amounts of chlorogenic acid and hyperoside in plants vary according to the regions where the samples were collected. As a result aerial parts of the S. latifolia collected from the Kars region have found to contain higher amount of chlorogenic acid (1246.78±3.20 µg/g) as well as hyperoside (652.32±2.48 µg/g) than other samples. The highest DPPH radical scavenging activity was determined with the IC50 value of 1.036 mg/mL for S. latifolia aerial parts of Kayseri sample. MDA level was detected as the lowest with treatment of S. latifolia Bayburt root sample (4.41 nmol/mL). According to the antioxidant activity results, no significant difference was observed in the antioxidant potential between the samples collected from different locations except for S. latifolia collected from the Kars region.

Green Synthesized Zinc-Glycine Chelate Enhances Antioxidant Protection of Pistachio under Different Soil Boron Levels

ABSTRACTZinc (Zn) and boron (B) disorders are common nutritional stresses in arid and semi-arid regions. In the current study, effectiveness of soil Zn amendment (0, 5.0, 10.0, and 20.0 mg kg–1 soil) using Zn-glycine chelate (Zn-Gly), a novel Zn-fertilizer, which is especially synthesized for application in calcareous soils in arid and semi-arid areas, was evaluated under different soil B levels (0, 2.5, 5.0, 10.0, and 20.0 mg kg–1 soil) for a 100-day period. Pistachio, the most valuable crop grown under arid conditions, was used as the model plant. Measurement of electrolyte leakage, H2O2, and malondialdehyde indicated the incidence of oxidative stress in the leaves of pistachio under low and high soil B concentrations. In addition, B stress caused a significant increase in lipoxygenase activity in the leaves. Plants treated with 5.0 mg B kg–1 soil showed the lowest oxidative stress injuries and lipid peroxidation. Application of 5.0 mg Zn kg–1 soil significantly alleviated the B stress damages, however, the ameliorative effect of Zn was vanished by application of higher Zn concentrations. Evaluation of the antioxidant enzymes (superoxide dismutase [SOD], catalase [CAT], or ascorbate peroxidase [APX]) and non-enzyme antioxidants (ascorbate and phenolic compounds) revealed that the protective effects of Zn-Gly against B stress are due to enhancement of cell antioxidant defense. In conclusion, application of Zn-Gly for reducing oxidative stress pressure in pistachio plants grown under B disorder was suggested.

Antioxidant and anti-inflammatory effects of dimethyl fumarate in hypercholesterolemic rabbits

The present study aimed to determine the possible beneficial effects of dimethyl fumarate (DMF) against oxidative stress and inflammation in hypercholesterolemic rabbits. Twenty four New Zealand male rabbits were randomly allocated into 4 groups as the following: Group I (control): rabbits received standard rabbit chow; Group II high cholesterol diet (HCD): rabbits received 1% cholesterol-enriched chow for 4weeks; Group III (HCD-DMF): rabbits received 1% cholesterol-enriched chow and administered DMF (12.5mg/kg/day, orally) for 4weeks; Group IV (DMF): rabbits received standard chow plus DMF (12.5mg/kg/day, orally) for 4weeks. At the end of experiment (day 30), blood samples were collected for measuring serum total cholesterol (TC), triglycerides (TGs), high-density lipoprotein cholesterol (HDL-C) and C-reactive protein (CRP). In addition, the aorta was removed for measurement of malondialdehyde (MDA), superoxide dismutase (SOD), mRNA expression of cholesteryl ester transfer protein (CETP) and histological assessment of intima/media (I/M) ratio. HCD-fed rabbits showed significant increases in TGs, TC, low-density lipoprotein cholesterol (LDL-C), aortic MDA and aortic I/M ratio levels while they significantly exhibited a reduced SOD level relative to control animals. Moreover, HCD rabbits demonstrated upregulated mRNA expression of CETP. DMF administration significantly decreased HCD-induced elevations in serum TC and LDL-C. Additionally, DMF decreased aortic level of MDA while increased SOD level. Moreover, DMF significantly downregulated mRNA expression of CETP and reduced the elevation in I/M ratio.In conclusion, this study suggests that DMF has the ability to improve HCD-induced vascular irregularities, possibly via its anti-inflammatory and antioxidant effect.

Lipid peroxidation in Gram-negative bacteremia modulates the risk for septic shock and infections by resistant Klebsiella pneumoniae.

Controversies in outcomes with the parenteral administration of antioxidants as adjuvant therapies led to the measurement of malondialdehyde (MDA), a product of lipid peroxidation, in serum collected from 120 patients with primary Gram-negative bacteremia during the first 24 h from sepsis onset. MDA was measured by the thiobarbiturate assay, followed by high-performance liquid chromatography (HPLC) analysis. After receiver operator characteristic (ROC) curve analysis, patients were divided into those with high levels of MDA and low levels of MDA. The primary endpoint was the association of the level of MDA with septic shock. The level of MDA as an index of neutrophil function and associations with outcome and with infections by carbapenem-resistant Klebsiella pneumoniae were the secondary endpoints. In total, 63 patients had high and 57 had low MDA levels; 27% and 49.1%, respectively, had septic shock (p = 0.015). The rate of the concentration of MDA to the total neutrophil count was used as an expression of neutrophil function; this was lower among patients with septic shock. The odds ratio (OR) for death among patients without septic shock and low level of MDA was 4.00; this was 0.48 for patients with septic shock (p = 0.020 between the two ORs). The OR for resistance to carbapenems among patients with bacteremia by K. pneumoniae and low level of MDA was 7.50 (p = 0.011 compared to patients with bacteremia by other pathogens). Low level of circulating MDA is associated with susceptibility to septic shock and infections by carbapenem-resistant K. pneumoniae.

Effect of chronic arsenic exposure under environmental conditions on bioaccumulation, oxidative stress, and antioxidant enzymatic defenses in wild trout Salmo trutta (Pisces, Teleostei).

The present study evaluates the relation between chronic arsenic (As) exposure in the natural distribution area of wild brown trout (Salmo trutta), oxidative stress and antioxidant enzymatic defenses. Two rivers of the same watershed were evaluated to highlight the correlation between As accumulation and the resulting stress: (i) the Presa River, which has high chronic As levels (2281.66 µg/L) due to past mining activity, and (ii) the Bravona River (control river). This metalloid was measured in main fish tissues (gills, kidney, liver, muscle, gonads and fins) and water. As organotropism in S. trutta was kidney > liver > gill > fin > gonad > muscle. The HepatoSomatic Index (HSI) and somatic condition (CF) were used to compare fish population conditions from both sites. Arsenic can be absorbed by the gills and can induce oxidative stress and disturb antioxidant defenses. The aim of this study was to evaluate oxidative stress response by measuring malondialdehyde (MDA) content, as a marker of lipid peroxidation, and antioxidant enzymatic defenses (Superoxide dismutase (SOD), catalase CAT, glutathione peroxidase (GPx) and glutathione S-transferase (GST)), in the main tissues of control and exposed trout. The highest MDA content was found in the kidney and liver of exposed trout. SOD and CAT activities in exposed livers and kidneys were considerably increased while a significant rise of GPx activity was observed only in the liver. GST activity was found to be significantly induced in the liver of exposed trout. The results demonstrate that arsenic bioaccumulation can induce lipid peroxidation and substantial modifications in antioxidant enzymatic defenses in main wild trout tissues.

Impact of Blocking Renin Angiotensin Aldosterone Axis in Acute Kidney Injury

Acute Kidney injury (AKI) is a common health problem especially the dug induced AKI as a side or toxic effect during treatment of different medical disorders. Local Renin angiotensin aldosterone system (RAAS) has been described in addition to the systemic RAAS and it is activated by renal injury. The aim of the current study was to evaluate and compare the renoprotective effect of inhibiting RAAS by losartan versus captopril on drug induced AKI. 36 male albino rats constituted the animal model and have been divided into 6 groups (6 rats/group): control, AKI, AKI+losartan, AKI+captopril, losartan, captopril groups. Systolic blood pressure, glomerular filtration rate (GFR) have been measured. Serum samples were collected for measurement of urea, creatinine, cystatin-c , Monocyte Chemoattractant Protein-1 (MCP-1) , Intercellular Adhesion Molecule 1 (ICAM-1) and Neutrophil gelatinase-associated lipocalin (NGAL). Kidney tissues were removed for measurement of tissue Malondialdehyde (MDA) and renal expression of Megalin, and kidney injury molecule 1(KIM1). Both captopril and losartan attenuated drug induced AKI as revealed from the measured serum and tissue parameters. Captopril was superior to losartan on normalizing ICAM-1, megalin and KIM-1, however; losartan improved GFR more than captopril. Other measured parameters showed no significant difference in AKI groups treated with losartan and groups treated with captopril.

The preventive and curative effects of melatonin against abdominal aortic aneurysm in rats

ObjectiveOxygen free radicals are important components involved in the histopathologic tissue alterations observed during abdominal aortic aneurysms (AAAs). This study examined whether melatonin has protective or therapeutic effects against AAAs. MethodsSprague-Dawley rats were divided into four groups. A CaCl2 model was used to induce AAA. Starting on the operation day (Mel+AAA+Mel group) or 4 weeks after the operation (AAA+Mel group), the rats received intraperitoneal melatonin (10 mg/kg/day) for 6 and 2 weeks, respectively. The control and AAA groups received vehicle for 2 weeks after the sham operation and AAA induction, respectively. Angiographic measurements were recorded at the beginning, week 4, and week 6 of the study. After decapitation, aorta tissues were taken for the measurement of malondialdehyde, 8-hydroxy-2′-deoxyguanosine, glutathione levels, and myeloperoxidase and caspase-3 activity. Matrix metalloproteinase (MMP)-2, MMP-9, tumor necrosis factor-α, and inducible nitric oxide synthase protein expressions were analyzed by Western blot technique. Aortic tissues were also examined by light microscopy. ResultsCaCl2 caused an inflammatory response and oxidative damage indicated by rises in malondialdehyde and 8-hydroxy-2′-deoxyguanosine levels. Myeloperoxidase and caspase-3 activities were increased, but glutathione levels were reduced. On the one hand, MMP-2, MMP-9, tumor necrosis factor-α, and inducible nitric oxide synthase protein expressions were increased in the vehicle-treated AAA group. On the other hand, melatonin treatment reversed all of these biochemical indices and histopathologic alterations. ConclusionsAccording to the data, although melatonin tended to reverse the biochemical parameters given on week 4, the preventive effect is more pronounced when given concomitantly with AAA induction because values were closer to the control levels.

Alterations of plasma concentrations of lipophilic antioxidants are associated with Guillain-Barre syndrome

BackgroundGuillain-Barré syndrome (GBS) is an acute inflammatory polyneuropathy resulting in demyelination in peripheral nervous system. Myelin enriched in lipids is easily oxidized by reactive oxygen species during inflammation. Oxidative stress and lipophilic anti-oxidative capacities in GBS patients have not been fully explored. To evaluate the redox status of GBS patients, we measured malondialdehyde (MDA), myeloperoxidase (MPO), lipophilic antioxidants, and tocopherols concentrations in plasma from GBS patients and age-matched healthy controls. ResultsConcentrations of γ-tocopherol and δ-tocopherol decreased significantly, and α-carotene significantly increased in GBS patients compared to healthy controls. However, no significant changes in MDA and MPO concentrations were detected. In GBS patients, the γ-tocopherol concentration correlated positively with concentrations of δ-tocopherol, α-tocopherol, lutein, Q10, and γ-CEHC, respectively. Similarly, the δ-tocopherol concentration correlated positively with γ-tocopherol, α-tocopherol, lutein, Q10, δ-CEHC, and γ-CEHC concentrations, respectively. The receiver operating characteristics curve analysis showed that γ-tocopherol may serve as a good predictor for GBS. ConclusionsDiminished lipophilic antioxidant defense, mainly γ-tocopherol and δ-tocopherol, in GBS patients accounting for their lowered resistance to reactive oxygen species is probably associated with pathogenesis of GBS, and potentially useful for the development of therapeutic strategies.

Detection of intracellular reactive oxygen species (superoxide anion and hydrogen peroxide) and lipid peroxidation during cryopreservation of alpaca spermatozoa.

The objective of this study was to detect changes in intracellular reactive oxygen species (superoxide anion and hydrogen peroxide) production and lipid peroxidation during cryopreservation of alpaca spermatozoa. Twelve alpaca semen samples were conventionally cryopreserved. Intracellular superoxide anion and hydrogen peroxide were evaluated by fluorescence microscopy using dihydroethidium (DHE)/YO-PRO-1 and dichlorofluorescein diacetate (H2DCFDA)/propidium iodide (PI), respectively. Evaluations were performed during cooling curve at (1) 25°C, (2) 15°C, (3) 5°C/0min, (4) 5°C/15min, (5) 5°C/30min and (6) after freezing/thawing. Evaluation of lipid peroxidation by measuring malondialdehyde (MDA) was performed at 25°C, 5°C/30min and after thawing. Maximum percentages of total spermatozoa producing superoxide anion and hydrogen peroxide were found at 5°C/30min (62.8±6.3% and 30.5±5.6%, respectively), and these results were higher (p<.05) than initial (25°C: 10.8±3.8% and 6.8±0.7%, respectively) and after thawing (29.8±9.5% and 7.5±1.8%, respectively) values. However, considering only viable spermatozoa, production of superoxide anion and hydrogen peroxide during overall stabilization at 5°C (>76% and >91%, respectively) and after thawing (74.9±5.0% and 78.9±2.2%, respectively) was higher (p<.05) than initial values at 25°C (38.7±3.1% and 53.6±2.0%, respectively). Lipid peroxidation at 25°C, 5°C/30min, and post-thawing were 346.5±99.8, 401.1±64.8 and 527.7±142.8ng/ml MDA, respectively. These results showed that high percentage of viable alpaca spermatozoa produces intracellular reactive species oxygen (ROS) during the cryopreservation process of alpaca semen.

Subchronic nandrolone administration reduces cardiac oxidative markers during restraint stress by modulating protein expression patterns.

Nandrolone decanoate (ND), an anabolic-androgenic steroid prohibited in collegiate and professional sports, is associated with detrimental cardiovascular effects through redox-dependent mechanisms. We previously observed that high-dose short-term ND administration (15mg/kg for 2weeks) did not induce left heart ventricular hypertrophy and, paradoxically, improved postischemic response, whereas chronic ND treatment (5mg/kg twice a week for 10weeks) significantly reduced the cardioprotective effect of postconditioning, with an increase in infarct size and a decrease in cardiac performance. We wanted to determine whether short-term ND administration could affect the oxidative redox status in animals exposed to acute restraint stress. Our hypothesis was that, depending on treatment schedule, ND may have a double-edged sword effect. Measurement of malondialdehyde and 4-hydroxynonenal, two oxidative stress markers, in rat plasma and left heart ventricular tissue, revealed that the levels of both markers were increased in animals exposed to restraint stress, whereas no increase in marker levels was noted in animals pretreated with ND, indicating a possible protective action of ND against stress-induced oxidative damage. Furthermore, isolation and identification of proteins extracted from the left heart ventricular tissue samples of rats pretreated or not with ND and exposed to acute stress showed a prevalent expression of enzymes involved in amino acid synthesis and energy metabolism. Among other proteins, peroxiredoxin 6 and alpha B-crystallin, both involved in the oxidative stress response, were predominantly expressed in the left heart ventricular tissues of the ND-pretreated rats. In conclusion, ND seems to reduce oxidative stress by inducing the expression of antioxidant proteins in the hearts of restraint-stressed animals, thus contributing to amelioration of postischemic heart performance.