The effects of CORM3 or NaHS on the oxidative stress caused by chronic kidney disease in rats: potential interaction between CO and H2S signaling pathway.

Neurotoxicity is implicated as a severe complication of chronic kidney disease (CKD). Accumulation of urea and other toxic compounds leads to oxidative stress, inflammation and destruction of the blood-brain barrier. Carbon monoxide (CO) and hydrogen sulfide (H2S) have been shown to have anti-inflammatory, anti-apoptotic, and anti-proliferative properties. The aims of the present study were evaluated the protective effects of CO-releasing molecule (CORM3) and H2S donor (NaHS) on oxidative stress and neuronal death induced by CKD in the hippocampus and prefrontal cortex by considering interaction between CO and H2S on CBS expression. CORM3 or NaHS significantly compensated deficits in the antioxidant defense mechanisms, suppressed lipid peroxidation and reduced neuronal death in hippocampus and prefrontal cortex and improvement the markers of renal injury that induced by CKD. In addition, CORM3 or NaHS significantly improved CBS expression which were reduced by CKD. However, improving effects of CORM3 on antioxidant defense mechanisms, lipid peroxidation, neuronal death, renal injury and CBS expression were prevented by amino-oxy acetic acid (AOAA) (CBS inhibitor) and reciprocally improving effects of NaHS on all above indices were prevented by zinc protoporphyrin IX (Znpp) (HO-1 inhibitor). In conclusion, this study demonstrated that formation of CO and H2S were interdependently improved CKD-induced oxidative stress and neuronal death, which is may be through increased expression of CBS.

The effect of tannic acid on renal renin-angiotensin signaling pathway in a model of unilateral ureteral obstruction in male Wistar rats.

The purpose of current study was to elucidate polyphenol tannic acid effect on renal function and activity of the renin-angiotensin system after unilateral ureteral obstruction (UUO). Male Wistar rats were divided into three groups of six randomly: 1) Sham, 2) UUO, and 3) UUO + Tannic acid. Rats in the UUO and UUO + Tannic acid groups experienced unilateral ureteral obstruction. In the Sham group, the abdominal cavity was exposed without UUO induction. In the UUO + Tannic acid group, animals received tannic acid (20 mg/kg) intraperitoneally, 6 and 12 h after clamping the left ureter and 6 and 12 h after the right nephrectomy. Blood samples were taken to measure blood urea nitrogen (BUN) and creatinine levels. Kidney tissue samples were obtained for assessment of oxidative stress, inflammatory indices and the levels of renin-angiotensin system components. Tannic acid administration significantly improved UUO-induced kidney dysfunction (serum BUN: 66.42 ± 14.414 mg/dl, p < 0.05; serum creatinine: 1.67 ± 0.258 mg/dl, p < 0.05), oxidative stress (MDA level: 95.29 ± 37.35 µmol/g tissue, p < 0.05; SOD activity: 59.82 ± 13.41 U/g protein, p < 0.01) and inflammation (renal TNF-α: 57.05 ± 15.653 pg/g tissue, p < 0.05; renal IL-6: 117.015 ± 24.076 pg/g tissue, p < 0.001). The treatment caused a reduction in the amount of renal angiotensinogen, renin and ACE genes expression compared to the UUO group (Angiotensinogen: 8.9 ± onefold, p < 0.05, Renin: 6.5 ± 1.14 fold, p < 0.05, ACE: 4.9 ± 0.64 fold, p < 0.05). Angiotensin II type 1 receptor protein levels decreased in the tannic acid-treated rats in comparison with the UUO group (0.61 ± 0.136, p < 0.05). According to the result of the current study, tannic acid considerably attenuated the complications of unilateral ureteral obstruction through renin-angiotensin system modulation. Trial registration: IR.TUMS.MEDICINE.REC.1400.802.

A comparison between centrally and systemically administered erythropoietin on kidney protection in a model of fixed-volume hemorrhagic shock in male rats.

BACKGROUND: In this study, a comparison between centrally and systemically administered erythropoietin (EPO) was performed on nephroprotection during hemorrhagic shock (HS) in male rats. METHODS: Male rats were allocated into four experimental groups. (1) Sham; a guide cannula was inserted into the left lateral ventricle and other cannulas were placed into the left femoral artery and vein. (2) HS; stereotaxic surgery was done to insert a cannula in the left lateral ventricle and after a 7-day recovery; hemorrhagic shock and resuscitation were performed. (3) EPO-systemic; the procedure was the same as the HS group except that animals received 300 IU/kg erythropoietin into the femoral vein immediately before resuscitation. (4) EPO-central; animals was treated with erythropoietin (2 IU/rat) into the left lateral ventricle before resuscitation. Arterial oxygen saturation (SaO2) was measured during experiments. Urine and renal tissue samples were stored for ex-vivo indices assessments. RESULTS: Erythropoietin (systemically/centrally administered) significantly improved SaO2, renal functional and oxidative stress parameters and decreased renal inflammatory (TNF-α and IL-6) mRNA expression compared to the HS group. EPO-treated groups showed a decrease in active form of caspase-3 protein level and an increase in autophagy activity in comparison with the HS group. CONCLUSION: Considering the fact that the effective dose of systemic EPO (300 IU/kg) was roughly 50 times higher than that of central administration (2 IU/rat), centrally administered EPO was accompanied by more advantageous consequences than systemic way. EPO is likely to act as a neuro-modulator or neuro-mediator in the central protection of organs including the kidneys.

Point-of-care salivary oxidative and renal functional markers to assess kidney function in reperfusion-induced acute kidney injury in male rats.

OBJECTIVES: Saliva is one of the most promising body fluids in the research of new biomarker for various diseases diagnosis. However, serial sampling in this condition is very dangerous and pose iatrogenic anemia with blood loss. This study was done to evaluate the cost-effectiveness of point-of-care salivary tests and identify the validity of salivary markers. METHODS: Rats were randomly assigned to four experimental groups: (1) control (2) IR-3 h (3) IR-6 h (4) IR-24 h. Both renal pedicles were occluded for 55 min and then were declamped to allow reperfusion for 3, 6 and 24 h in IR groups. After reperfusion, all rats received pilocarpine 1 mg/kg to collect saliva. Plasma samples were also collected. Renal parameters including Cr, uric acid, and urea, malondialdehyde (MDA) levels, Bax/Bcl2 ratio, nitrite/nitrate ratio, corticosterone levels and oxidant/antioxidant ratio were measured in both plasma and salivary samples. RESULTS: There were significant increased level of renal function parameters, MDA levels, Bax/Bcl2 ratio, nitrite/nitrate ratio and corticosterone in both saliva and plasma. The comparison of above parameters in both saliva and plasma showed significant correlation. CONCLUSIONS: This study demonstrated that concentrations of indices specifically renal functional parameters increase in saliva in the IR-induced kidney injury in male rats and result indicate the potential of saliva as a tool to monitoring AKI. Measurement of salivary parameters may can become reliable diagnostic tests for patients with AKI.

Therapeutic effects of CORM3 and NaHS in chronic kidney disease induced cognitive impairment via the interaction between carbon monoxide and hydrogen sulfide on Nrf2/HO-1 signaling pathway in rats.

Cognitive impairment is one of the major complications of chronic kidney disease (CKD). The present study aims to evaluate the protective effects of carbon monoxide (CO) and hydrogen sulfide (H2S) and their interactions on CKD-induced cognitive deficits by considering the Nrf2/HO-1 signaling pathway. Sixty rats were divided into six experimental groups: sham, five-sixth (5/6) nephrectomy (CKD), CKD + H2S donor (NaHS), CKD + CO-releasing molecule (CORM3), CKD + NaHS and zinc protoporphyrin IX (Znpp), CKD + CORM3 and amino-oxy acetic acid (AOAA). Eleven weeks after 5/6Nx, behavioral tests (Novel object recognition test, Passive avoidance test and Barnes maze test) were performed to evaluate the cognitive level. At the end of the twelfth week, blood urea nitrogen (BUN) and serum creatinine (sCr) levels, as well as the expression levels of nuclear factor-erythroid factor 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1), and neuronal loss in the hippocampus and prefrontal cortex were evaluated. CKD caused enhancement of BUN and sCr, reduction of Nrf2 and HO-1 proteins and enhancement of neuronal loss in the hippocampus and prefrontal cortex. In addition, CKD led to cognitive disturbances and memory impairment. CORM3 and NaHS returned all above indices to the levels measured in the control group. However, improving effects of CORM3 on cognitive impairment and Nrf2/HO-1 signaling pathway were prevented by AOAA and decreased H2S level as well as reciprocally improving effects of NaHS on cognitive disturbances and Nrf2/HO-1 signaling pathway were prevented by Znpp and decreased CO level. In conclusion, this study demonstrated that formation of CO and H2S were interdependently improved CKD-induced cognitive dysfunctions, through interaction with Nrf2/HO-1 signaling pathway.

Mesenchymal stem cells and their conditioned medium as potential therapeutic strategies in managing comorbid anxiety in rat sepsis induced by cecal ligation and puncture.

Objectives: Sepsis-associated encephalopathy (SAE) is a common brain dysfunction following sepsis. Due to the beneficial effects of mesenchymal stem cells (MSCs) therapy on anxiety, an extreme and early manifestation of SAE, we hypothesized that MSCs-derived conditioned medium (CM) may be able to attenuate anxiety in cecal ligation and puncture (CLP)-induced sepsis. Materials and Methods: Rats were assigned into 4 groups: sham, CLP, MSC, and CM. All animals, except in the sham group, underwent the CLP procedure to induce sepsis. Two hours after sepsis induction, the rats in MSC and CM groups, received 1×106 MSCs and CM derived from the same number of cells, respectively. 48 hr after the treatments, anxiety-related behaviors were assessed, and brain and right hippocampal tissues were collected. Results: MSCs and CM enhanced the percentages of open arm entries and time spent in the open arms of the elevated plus-maze and the time spent in the light side of the light-dark box. MSCs and CM decreased the Evans blue content and decreased the IL-6 and TNF-α levels in the brain tissue samples. Reductions in the expression of 5-HT2A receptors and phosphorylation of ERK1/2 and an increase in the expression of 5-HT1A receptors in the hippocampal tissue samples were observed in the MSC and CM groups. Conclusion: MSCs and MSCs-derived CM attenuated anxiety-related behaviors to an equal extent by reducing inflammation, modifying 5-HT receptor expression changes, and inhibiting the ERK pathway. Therefore, MSCs-derived CM may be considered a promising therapy for comorbid anxiety in septic patients.

Nephroprotection through Modifying the Apoptotic TNF-α/ERK1/2/Bax Signaling Pathway and Oxidative Stress by Long-term Sodium Hydrosulfide Administration in Ovalbumin-induced Chronic Asthma.

Asthma is one of the most common respiratory diseases in the world. Nevertheless, it is reported that inflammation induced by asthma is not only restricted to the lung and may cause damaging effects on remote organs. Therefore, this study was designed to investigate the beneficial effects of long-term sodium hydrosulfide (NaHS) administration on lung inflammation and oxidative stress markers to protect the kidney during chronic asthma. BALB/c mice were divided into three groups (n = 5-7): control, asthma and NaHS. Except the control group, sensitization and challenge were performed with ovalbumin. The NaHS group intraperitoneally received 14 µmol/kg NaHS 30 min before each challenge. 24 h after the last challenge, samples of bronchoalveolar lavage fluid (BALF), plasma, lung and kidney tissues were collected. NaHS administration significantly decreased total white blood cell count, percentages of eosinophils, neutrophils and macrophages and increased percentage of lymphocytes. Administration of NaHS considerably decreased the levels of BALF interleukin-13, plasma tumor necrosis factor-alpha (TNF-α), lung malondialdehyde (MDA) and lung phosphorylated nuclear factor-kappa B (p-NF-κB) expression and scores of peribronchial inflammatory cell infiltration, goblet cell hyperplasia and subepithelial fibrosis and increased the activity of lung superoxide dismutase (SOD). The MDA levels and expressions of p-ERK1/2 and Bax were decreased and SOD activity and expressions of Bcl-2 and p-Akt were significantly increased in kidney tissues by NaHS administration. Administration of NaHS decreased renal oxidative stress indices and reduced apoptosis by the inhibition of TNF-α/ERK1/2/Bax. Therefore, H2S may have an essential role in renal protection during asthma.

Beneficial effects of combination therapy with testosterone and hydrogen sulfide by reducing oxidative stress and apoptosis: Rat experimental varicocele model.

Background: Despite the effectiveness of testosterone therapy in conditions associated with testosterone deficiency, including varicocele, several dose-dependent side effects limit the clinical use of testosterone therapy. Hydrogen sulfide, a toxic gas in high concentrations but a beneficial molecule in low concentrations, acts as both a major effector and an important inducer of testosterone. Objective: This study investigated whether a subeffective dose of testosterone combined with a subeffective dose of hydrogen sulfide donor sodium hydrosulfide (NaHS) can be effective in an experimental varicocele model through a possible additive effect. Materials and Methods: Thirty Wistar rats weighing 200-250 gr were divided into 5 groups as (n = 6/each): sham, varicocele, testosterone (200 µg/kg, 5 times per wk for 4 consecutive weeks), NaHS (15 µmol/L, daily for 4 consecutive wk) and testosterone + NaHS (200 µg/kg, 5 times per wk + 15 µmol/L, daily, both for 4 consecutive wk). All animals, except in the sham group, underwent varicocele induction. Results: The coadministration of testosterone and NaHS significantly increased serum testosterone (10.23 ± 0.95, p = 0.01), testicular H2S levels (608.94 ± 21.09, p < 0.001), and testicular superoxide dismutase activity (66.14 ± 1.56, p < 0.001), decreased malondialdehyde levels (0.77 ± 0.52, p < 0.001), and B-cell lymphoma 2-associated X protein to B-cell lymphoma 2 (0.16 ± 0.01, p < 0.001) protein expression ratio in the testicular tissues and improved sperm parameters and testicular histopathology compared to the varicocele group. Conclusion: The combination therapy of subeffective doses of testosterone and NaHS can attenuate the varicocele-induced damages by reducing testicular oxidative stress and apoptosis and thus can be considered an effective approach with fewer side effects.

Sperm and testicular dysfunction during cecal ligation and puncture-induced sepsis in male rats and effects of tannic acid through reducing testicular oxidative stress and inflammation.

Objectives: One of the problems caused by infectious diseases is the decrease in sperm count and motility. Tannic acid is known as an anti-oxidant and anti-inflammatory agent. In this study, Cecal Ligation and Puncture (CLP) sepsis model was induced to investigate the effect of tannic acid on oxidative stress and inflammation in testicular and sperm structure and function. Materials and Methods: Twenty-four male Wistar rats (250-300 g) were randomly divided into 3 groups of 8: 1) sham, 2) sepsis, and 3) sepsis + tannic acid (20 mg/kg at 6, 12, and 24 hr after sepsis induction). Thirty hours after induction of sepsis, testicular samples were collected to measure SOD activity and MDA, IL-6, and TNF-α levels. Another part of the testis was fixed in 10% formalin for histological examinations. Results: In the sepsis group, testicular MDA, TNF-α, and IL-6 levels increased and SOD activity decreased compared with the sham group. In addition, the percentage of motile sperm and the survival rate of sperm decreased significantly in the sepsis group. Administration of tannic acid significantly decreased inflammatory markers (TNF-α and IL-6) and MDA levels and increased SOD activity. Furthermore tannic acid significantly improved sperm parameters and increased sperm and animal survival rates. Conclusion: The results of this study showed that the reproductive system may be strongly affected by the conditions created during sepsis. Tannic acid improved reproductive dysfunction in sepsis by reducing oxidative stress and inflammation.

The Impact of Sex Differences on Renal Protective Effects of Lipopolysaccharide Preconditioning in Septic Shock.

BACKGROUND: Induction of septic shock by lipopolysaccharide (LPS) may lead to acute renal failure. The present study aimed to investigate the impact of sex differences on the effectiveness of low-dose LPS preconditioning (LPS-PC) on LPS-induced acute renal failure in rats. METHODS: This study was conducted at Tehran University of Medical Sciences, in 2017. A total of 48 Wistar rats were equally divided into two groups of male and female rats. The rats in each group were then allocated to three groups (n=8 per group), namely control, septic shock, and LPS-PC group. A high dose of LPS was administered for septic shock induction. LPS-PC was induced by injecting LPS before sepsis induction. The effect of sex differences on renal functional indices, renal oxidative stress markers, plasma tumor necrosis factor-α level, and renal histological changes was evaluated. Data were analyzed using two-way ANOVA followed by Tukey's post hoc test. RESULTS: In the septic shock groups, renal functional parameters (creatinine [Cr] and blood urea nitrogen [BUN]) were increased in both sexes. However, the increase was more significant in male rats (male rats: Cr=2.14±0.13, BUN=81±4.15; female rats: Cr=1.64±0.12, BUN=50±2.7). LPS-PC reduced these indices in both sexes (male rats: Cr=1.24±0.03, BUN=57±4.1; female rats: Cr=0.86±0.02, BUN=30.31±2.25). Renal superoxide dismutase (SOD) activity (male rats: 11.54±1.34, female rats: 24.4±2.04) and catalase (CAT) activity (male rats: 15±1.74, female rats: 25.75±1.97) were significantly higher in the female septic group. LPS-PC significantly increased SOD (male rats: 25.7±2.45, female rats: 42.6±3.31) and CAT (male rats: 37.25±2.34, female rats: 59.21±3.29) activities in renal tissue samples in the LPS-PC group in both sexes compared to the septic groups. In the LPS groups, plasma tumor necrosis factor-α (male rats: 375±25.65, female rats: 285.45±25.94) were significantly higher than in the LPS-PC groups (male rats: 250±21.35, female rats: 121±24.14). CONCLUSION: Male rats were more susceptible to sepsis-induced renal damage. LPS-PC had protective effects on the LPS-induced renal injury, and these effects were most prominent in female rats.

An overview of high-mobility group box 1, a potent pro-inflammatory cytokine in asthma.

High-mobility group box 1 (HMGB1), also called amphoterin, HMG1 and p30, is a highly conserved protein between different species that has various functions in nucleus such as stabilization of nucleosome formation, facilitation of deoxyribonucleic acid (DNA) bending and increasing the DNA transcription, replication and repair. It has also been indicated that HMGB1 acts as a potent pro-inflammatory cytokine with increasing concentrations in acute and chronic inflammatory diseases. Asthma is a common chronic respiratory disease associated with high morbidity and mortality rates. One central characteristic in its pathogenesis is airway inflammation. Considering the inflammatory role of HMGB1 and importance of inflammation in asthma pathogenesis, a better understanding of this protein is vital. This review describes the structure, cell surface receptors, signaling pathways and intracellular and extracellular functions of HMGB1, but also focuses on its inflammatory role in asthma. Moreover, this manuscript reviews experimental and clinical studies that investigated the pathologic role of HMGB1.

Adipose-Derived Mesenchymal Stem Cells and Conditioned Medium Attenuate the Memory Retrieval Impairment During Sepsis in Rats.

In this study, we hypothesized that sepsis induction impairs memory retrieval in rats while transplanted mesenchymal stem cells (MSCs) and MSC-conditioned medium (MSC-CM) application are capable of attenuating those complications. MSCs were obtained from adipose tissue of rats and at the second culture passage; MSCs and MSC-CM were collected. Rats were randomly divided into four experimental groups: sham, CLP, MSC, and MSC-CM. Sepsis was induced by cecal ligation and puncture (CLP) model in the CLP, MSC, and MSC-CM groups. The MSC group received 1 × 106 MSCs/rat (i.p., 2 h after CLP surgery); the MSC-CM rats received the conditioned medium (CM) from 1 × 106 MSCs intraperitoneally 2 h after sepsis induction. Novel object recognition test, sepsis score, and blood pressure measurement were performed 24 h after the treatments. The right hippocampus was taken for western blot analysis. CLP rats showed a significantly higher sepsis score and systolic blood pressure. They also had a significant increase in the phosphorylated form of CAMKII-α, cleaved caspase 3 and Bax/Bcl2 ratio, and a reduction in c-fos protein in the hippocampus tissue samples compared with the sham group. MSC transplantation and MSC-CM administration significantly decreased the mean sepsis score and prevented sepsis-induced attenuation of blood pressure compared with the CLP rats. Animals in the MSC and MSC-CM groups showed a better memory retrieval, attenuation in phosphorylated form of CAMKII-α, cleaved caspase 3 and Bax/Bcl2 ratio, and an increase in c-fos protein expression compared with the CLP group. It seems that CAMKII and c-fos are inversely involved in regulating memory processes in hippocampus. Phosphorylated form of CaMKII-α overexpression may impair the ability of object recognition. Our findings confirmed that MSC-CM application has more advantages compared with transplanted MSCs and may be offered as a promising therapy for inflammatory diseases such as severe sepsis.

Administration of sodium hydrosulfide reduces remote organ injury by an anti-oxidant mechanism in a rat model of varicocele.

OBJECTIVES: Infertility in varicocele may have an adverse outcome on the future life of an infertile male. This study was designed to investigate whether varicocele affects remote organs, including the kidney, liver, and brain. We have also evaluated the protective effects of NaHS administration on the structure and function of these organs. MATERIALS AND METHODS: Thirty-six rats were randomly assigned to 3 experimental groups: 1) Sham, 2) Varicocele, and 3) Varicocele + sodium hydrosulfide. Varicocele was induced via partial ligation of the left renal veins. Animals in the Varicocele + sodium hydrogen sulfide group received 30 µmol/l NaHS in drinking water for 56 days. On the 57th day of the treatment, blood samples, as well as kidney, liver, and brain tissues, were collected to assess kidney and liver functions, measurement of oxidative stress markers, and histological changes. For evaluation of sperm parameters caudal epididymis was used. The behavioral tests were performed to evaluate the animal's anxiety-related behaviors. RESULTS: Varicocele caused significant decrease in sperm parameters (motility and viability) and superoxide dismutase activity in the kidney, liver, and brain tissue. Anxiety-related parameters decreased in varicocele. Moreover, varicocele resulted in a significant increase in malondialdehyde levels in the kidney, liver and brain tissue, and liver function enzymes. Varicocele did not alter kidney function parameters. The administration of NaHS improves the above parameters. CONCLUSION: This study showed that notice to remote organs such as the liver and brain beside reproductive organs in varicocele is important. The administration of NaHS improved remote organ injury in varicocele via its anti-oxidant mechanism.

Protective effects of ascorbic acid and calcitriol combination on airway remodelling in ovalbumin-induced chronic asthma.

Context: Airway remodelling is one of the most refractory problems in asthma. According to the critical roles of oxidative stress and inflammation in airway remodelling, it is supposed that ascorbic acid and calcitriol have beneficial effects. However, a combination of antioxidants may be more effective for asthma therapy.Objective: This study investigated the protective effects of ascorbic acid in combination with calcitriol on airway remodelling in ovalbumin (OVA)-induced chronic asthma.Materials and methods: BALB/c mice were assigned into seven groups: (1) Control; (2) Asthma; (3) Ineffective C (orally 39 mg/kg ascorbic acid); (4) Ineffective D (intraperitoneally 1.5 µg/kg calcitriol); (5) Effective C (orally 130 mg/kg ascorbic acid); (6) Effective D (intraperitoneally 5 µg/kg calcitriol); (7) Combination (orally 39 mg/kg ascorbic acid + intraperitoneally 1.5 µg/kg calcitriol). All animals were sensitized and challenged with OVA except in the control group (normal saline). In all treatment groups, mice were administrated vitamins 30 min before each challenge (three times per week for 8 consecutive weeks).Results: In comparison with the asthma group, co-administration of ineffective doses of ascorbic acid and calcitriol led to the decreased levels of IL-13 (50.5 ± 1.85 vs. 42.13 ± 0.37 pg/mL, p = 0.02) and IgE (58.74 ± 0.43 vs. 45.78 ± 2.05 ng/mL, p = 0.003) as well as the reduction of goblet hyperplasia and subepithelial fibrosis (5 vs. 1 score, p = 0.001 and 5 vs. 2 score, p = 0.001, respectively).Discussion and conclusions: Combination of ascorbic acid with calcitriol in ineffective doses improves airway remodelling due to additive effects possibly through reduction of oxidative stress and inflammation. This study provides a scientific basis for further research and clinical applications of ascorbic acid and calcitriol and can be generalized to the broader pharmacological studies.

Long-term NaHS administration reduces oxidative stress and apoptosis in a rat model of left-side varicocele.

The main aim of this study was to assay the testicular H2 S levels in the varicocele rat model and then to investigate the protective effects of NaHS on morphometric changes, sperm parameters, oxidative stress and apoptosis markers in rat's testis. D,L-propargylglycine (PAG) was administrated to show the effects of cystathionine γ-lyase enzyme (CSE) inhibition in the varicocele. Rats were assigned to four groups: (a) Sham, (b) varicocele, (c) varicocele + PAG and (d) varicocele + NaHS. Animals in varicocele + NaHS group received 30 µmol/L NaHS in drinking water for 56 days. In the varicocele + PAG group, animals received PAG 19 mg/kg twice a week. Morphometric assessment, oxidative stress markers, testicular H2 S levels, sperm parameters, TUNEL assay and expression of Bax/Bcl2 were evaluated at the end of experiment. Testicular H2 S levels were significantly decreased in varicocele group. NaHS significantly improved sperm parameters, morphometric characteristics and oxidative stress compared to varicocele group. Oxidative stress status deteriorated in the PAG group compared to the varicocele group. This study showed that a low testicular H2 S level might play a critical role in male infertility. Thus, NaHS administration may be a promising treatment strategy for male infertility in varicocele. In addition, CSE may not be the only important enzyme in testicular H2 S production.

Combination of ascorbic acid and calcitriol attenuates chronic asthma disease by reductions in oxidative stress and inflammation.

Airway inflammation and oxidative stress are the two major characteristics of asthma pathogenesis. Therefore, this study evaluated the protective effects of ascorbic acid in combination with calcitriol on the oxidative damages and inflammation in asthma model. All animals, except in the control group, were sensitized and challenged with ovalbumin. One day after the last challenge, samples of bronchoalveolar lavage fluid was collected for the assessment of total white blood cell counts and differential count of white blood cell and plasma was used for the measurement of pro-oxidant/antioxidant balance level. Lung tissue samples were also stored for examining peribronchial inflammatory cell infiltration, phosphorylated nuclear factor-kappa B expression and measurement of malondialdehyde level. Induction of asthma caused significant increases in total white blood cell counts, percentage of neutrophils and eosinophils and a decrease in the percentage of lymphocytes. Moreover, asthma resulted in significant increases of peribronchial inflammatory cell infiltration, phosphorylated nuclear factor-kappa B expression and malondialdehyde level. However, no significant changes were observed in pro-oxidant/antioxidant balance level with the induction of asthma. Co-administration of low doses of ascorbic acid and calcitriol returned all to the levels measured before sensitization and challenge. Combination of low doses of ascorbic acid with calcitriol improves mouse asthma model by a possible additive effects through the decrease of oxidative stress and inflammation.

Additional effects of erythropoietin pretreatment, ischemic preconditioning, and N-acetylcysteine posttreatment in rat kidney reperfusion injury

Background/aim: Since the nature of ischemia/reperfusion (IR)-induced tissue damage is multifactorial and complex, in the current study, the effects of multiple treatment strategies via concomitant administration of erythropoietin (EPO) and N-acetylcysteine (NAC) with an ischemic preconditioning (IPC) regimen on renal IR injury were examined. Materials and methods: Thirty male Wistar rats were subjected to bilateral occlusion of the renal pedicles for 50 min followed by reperfusion. EPO (1000 IU/kg) was administered for 3 days, as well as IPC before the IR and NAC (150 mg/kg) administration for 4 days after IR. The animals were randomly allocated into 6 groups (n = 5): sham, IR, EPO+IR, IPC+IR, NAC+IR, and EPO+IPC+NAC+IR. Kidney tissues and blood samples were obtained for oxidative stress, proinflammatory cytokines, and renal functional evaluations. Results: IR caused significant inflammatory response, oxidative stress, and reduced renal function. Treatment with EPO, IPC, and NAC or a combination of two of them attenuated renal dysfunction and reduced the oxidative stress and inflammatory markers. Rats treated with the combination of EPO, IPC, and NAC showed a higher degree of protection compared to the other groups. Conclusion: These results showed that concomitant administration of EPO and IPC along with posttreatment NAC may have additive beneficial effects on kidney IR injury during IR-induced acute renal failure.

Inducible and endothelial nitric oxide synthase distribution and expression with hind limb per-conditioning of the rat kidney.

INTRODUCTION: We recently reported that a series of brief hind limb ischemia and reperfusion (IR) at the beginning of renal ischemia (remote per-conditioning - RPEC) significantly attenuated the ischemia/reperfusion-induced acute kidney injury. In the present study, we investigated whether the nitric oxide synthase (NOS) pathway is involved in the RPEC protection of the rat ischemic kidneys. MATERIAL AND METHODS: Male rats were subjected to right nephrectomy and randomized as: (1) sham, no additional intervention; (2) IR, 45 min of renal ischemia followed by 24 h reperfusion; (3) RPEC, four 5 min cycles of lower limb IR administered at the beginning of renal ischemia; (4) RPEC+L-NAME (a non-specific NOS inhibitor, 10 mg/kg, i.p.) (5) RPEC + 1400W (a specific iNOS inhibitor, 1 mg/kg, i.p.). After 24 h, blood, urine and tissue samples were collected. RESULTS: The protective effect of RPEC on renal function, oxidative stress indices, pro-inflammatory marker expression and histopathological changes of kidneys subjected to 45 min ischemia were completely inhibited by pretreatment with L-NAME or 1400W. It was accompanied by increased iNOS and eNOS expression in the RPEC group compared with the IR group. CONCLUSIONS: These findings suggest that the protective effects of RPEC on renal IR injury are closely dependent on the nitric oxide production after the reperfusion and both eNOS and iNOS are involved in this protection.

Protective effects of celecoxib on ischemia reperfusion-induced acute kidney injury: comparing between male and female rats.

OBJECTIVES: There is increasing evidence for the importance of gender in different diseases; however, the role of gender in response to treatments is still unknown. Therefore, this study investigated the impact of gender on the protective effects of celecoxib in ischemia reperfusion (IR)-induced acute kidney injury. MATERIALS AND METHODS: In this experimental study, rats were randomly divided into 6 groups (n=6): IR, sham and celecoxib groups of males and females. In IR groups, after orally receiving saline for 5 days, renal pedicles were clamped for 55 min and then kidneys were reperfused for 24 hr. In the sham groups, clamping of renal pedicles was not performed. In the celecoxib groups, 30 mg/kg celecoxib was given orally for 5 days before induction of ischemia. Plasma was collected to determine creatinine (Cr) and blood urea nitrogen (BUN). Kidney tissue samples were also stored for examining the histopathology and measuring malondialdehyde (MDA) levels and superoxide dismutase (SOD) activities. RESULTS: IR caused significant increases in plasma Cr (P<0.05), BUN (P<0.05) and renal histopathological damages in both genders. Also, induction of IR resulted in significant increase of MDA levels (P<0.05) and decrease of SOD activities (P<0.05) in the kidney in both genders. Celecoxib administration prevented the IR-induced functional, histopathological and oxidative changes in both genders by similar degrees. CONCLUSION: This study suggested that in similar pathological conditions, celecoxib improves renal function and histopathological damages and attenuates oxidative stress in both genders by the same degrees. These protective effects of celecoxib on IR-induced kidney injury are gender-independent.

Long-term exercise restores hydrogen sulfide in the kidney and contributes to exercise benefits in 5/6 nephrectomized rats.

Physical exercise is shown to have protective effects on chronic kidney disease (CKD). CKD itself is associated with a reduction in renal hydrogen sulfide (H2S) concentration. This study was designed to investigate whether protective effects of exercise in 5/6 nephrectomized (5/6 NX) rats is associated with H2S levels in the kidney? Twenty four male Wistar rats weighing 250-300 g were assigned into 4 groups: 1- Sham 2- Sham exercise 3-5/6 NX 4-5/6 NX+exercise. To induce CKD, 4 days after removing upper and lower one-third parts of the left kidney, total right nephrectomy was performed. In the Sham groups, anesthesia and surgery were performed like the other groups without removal of the kidney mass. Exercise was performed by treadmill at a speed of 18 m/min for 8 weeks. At the end of the twelfth week, blood and kidney samples were collected to measure renal function (levels of plasma urea and creatinine), oxidative stress markers (renal MDA level and SOD activity), and histological indices. Eight weeks exercise significantly improved serum creatinine, BUN, renal MDA level, SOD activity, renal sympathetic nerve activity (RSNA), hypertension, and renal histology in addition to renal H2S level compared to the 5/6 NX group. The results suggest that regular exercise improves renal oxidative status and ameliorates renal damage, hypertension, and RSNA in 5/6 nephrectomized rats. These improvements by exercise might be associated with the increase in renal H2S level.