Amlodipine: Can act as an antioxidant in patients with transfusion-dependent ß-thalassemia? A double-blind, controlled, crossover trial.

BACKGROUND AND AIM: This study aimed to assess the antioxidant effects of amlodipine in transfusion-dependent ß-thalassemia (TDT) patients. METHODS: This crossover trial consisted of two sequences (AP and PA). In the AP sequence, nine cases received amlodipine 5 mg daily (phase I) and then were switched to placebo (phase II). In PA sequence, 10 patients took the placebo (phase I) and were shifted to amlodipine (phase II). The washout period was 2 weeks. The length of each phase was 6 months. Serum malondialdehyde (MDA, µmol/L), carbonyl (protein CO, µM/L), glutathione (GSH, nM/L), and total antioxidant capacity (TAC, µmol FeSO4/L) were measured in the beginning and at the end of phases I and II. The clinical significance was viewed as a minimum change difference of 5% for each outcome between amlodipine and placebo. RESULTS: Seventeen cases completed the study. According to the baseline MDA values, the adjusted Hedges's g for MDA was -0.59, 95% confidence interval [CI] -1.26 to 0.08. After controlling the baseline protein CO values, Hedges's g computed for protein CO was -0.11, 95% CI -0.76 to 0.55. The estimated values of the adjusted Hedges's g for GSH and TAC were also 0.26, 95% CI -0.40 to 0.91, and 0.42, 95% CI -0.24 to 1.09, respectively. The change difference for MDA was 8.3% (protein CO 2.2%, GSH 3.1%, and TAC 12.9%). CONCLUSION: Clinically, amlodipine therapy is an efficacious adjuvant treatment with conventional iron chelators for improving the levels of MDA and TAC in patients with TDT.

Zinc and selenium supplement mitigated valproic acid-induced testis toxicity by modulating the oxidative redox balance in male rats.

Valproic acid (VPA) is widely used antiepileptic agent which is associated with reproductive toxicity via impairment in oxidative redox. Zinc (Zn) and selenium (Se) are trace element with antioxidant effect that known to be essential for spermatogenesis. In the current study, the protective effect of co-administration of Zn and Se on VPA-induced reproductive toxicity in male rats was evaluated. Forty-eight male rats were divided into 8 groups of six (n=6): Control group (treated with normal saline); VPA only (250, 500, 1,000 mg/kg) group; VPA (500 mg/kg) plus Zn (2 mg/kg) group; VPA (500 mg/kg) plus Se (1.5 mg/kg) group; VPA (500 mg/kg) plus a combination of Zn and Se group; and VPA+vitamin E (20 mg/kg) group. The Animals were sacrificed after 28 days of treatment and sperm analysis was taken. Also, evaluation of oxidative stress markers including malondialdehyde (MDA), protein carbonyl (PC), glutathione (GSH) and histopathological changes were done on testis tissue. Morphological changes and a significant decrease in motility and sperm count in rats treated with VPA were observed. Also, an increase in oxidative stress marker, including MDA and PC and a decrease in GSH level was evident in VPA group. Zn and Se administration was able to protect against sperm abnormality, ameliorate the histological change in testis tissue, and suppressed the increase in oxidative stress markers induced by VPA. These results indicated that combination therapy with Zn and Se showed better an ameliorative effect than each one alone. Therefore, it can be suggested as an effective supplement for reproductive impairment in VPA-treated patient.

Ginkgo biloba attenuated hepatotoxicity induced by combined exposure to cadmium and fluoride via modulating the redox imbalance, Bax/Bcl-2 and NF-kB signaling pathways in male rats.

Aim of this study was to investigate the efficacy of Ginkgo Biloba (G.B) hydro-ethanolic extract against hepatotoxicity induced by combined exposure to cadmium (Cd) and fluoride (F) in Wistar rats. Animals were exposed to F (30 mg/L) + Cd (40 mg/L), F + Cd plus G.B (50,100 and 200 mg/kg), G.B (200 mg/kg), F + Cd plus Vit C(1000 mg/L) in drinking water for 42 days. Significant raise in liver enzymes and histopathological changes were observed in F + Cd treated rats. F + Cd exposure enhanced protein and glutathione oxidation, lipid peroxidation and decreased superoxide dismutase activity. F and Cd combination also caused mitochondrial dysfunction, swelling and mitochondrial membrane potential collapse in liver isolated mitochondria. Up-regulation of inflammatory genes (TNF-α, IL-1ß and NF-kB) and pro-apoptotic Bax as well as down-regulation of anti-apoptotic Bcl-2 were detected after co-exposure to F and Cd. Interestingly, G.B alleviated F + Cd induced liver oxidative stress, mitochondrial damage and prevented inflammation and apoptosis. Furthermore, decrease in serum liver enzymes and improvement of histopathologic lesions were observed in G.B treated rats. This study explored the potential beneficial role of G.B on F + Cd combined hepatotoxic effects via considering its possible antioxidant, anti-inflammatory, mitochondrial protection and anti-apoptotic effects.

Modulatory effects of Viola odorata flower and leaf extracts upon oxidative stress-related damage in an experimental model of ethanol-induced hepatotoxicity.

Ethanol is the most widely abused drug in the world and its long-term use induces oxidative stress in the liver tissue. The aim of this study was to evaluate protective effect of Viola odorata against ethanol-induced hepatotoxicity in Wistar rat. Animals were divided into 9 groups as follows: control (normal saline), ethanol (10 mg/kg, intraperitoneally), ethanol with 3 doses (125, 250, and 500 mg/kg) of ethyl acetate flower and leaf extracts, and positive control (vitamin E 80 mg/kg). Animals were gavaged 30 min before ethanol injection for 28 days. Then, animals were killed and the livers were separated. Oxidative stress parameters, including reactive oxygen species, lipid peroxidation, and protein carbonyl as well as glutathione content, were evaluated. Also, histopathological examination was performed and assessment of blood alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, and total antioxidant capacity were evaluated. Ethanol significantly increased oxidative stress markers in liver. Interestingly, administration of both extracts significantly decreased oxidative stress markers in liver tissue and biochemical parameters in the plasma. In addition, abnormal pathological features were improved after treatment with flower and leaf extracts. These results suggested that V. odorata can be considered a candidate for improving conditions due to ethanol-induced tissue oxidative damage because of its antioxidant activity.

Mitochondrial dysfunction contribute to diabetic neurotoxicity induced by streptozocin in mice: protective effect of Urtica dioica and pioglitazone.

INTRODUCTION: Uncontrolled chronic hyperglycemia in diabetic patients could result in various complications, including neurotoxicity. Urtica dioica L. (UD) is known for its hypoglycemic and antioxidant effects. In this study, we evaluated the efficacy of UD and pioglitazone (PIO) in reduction of neurotoxicity and oxidative stress in streptozocin-induced diabetic mice. MATERIALS AND METHODS: Male mice were divided into seven groups: control, diabetic, dimethyl sulfoxide-treated control, PIO-treated, UD-treated, UD-PIO-treated, and vitamin E-treated. For induction of diabetes, streptozocin was injected in a single dose (65 mg/kg, i.p.). All treatments were performed for 5 weeks. Neurotoxicity was evaluated through hot plate and formalin test. Then, animals were killed, brain tissue was separated and the mitochondrial fraction was isolated with different centrifuge technique. Also, oxidative stress markers (reactive oxygen species, lipid peroxidation, protein carbonyl, glutathione) were measured in brain. Mitochondrial function was evaluated by MTT test in brain isolated mitochondria. RESULTS: Elevation of oxidative stress markers and mitochondrial damage were observed in diabetic mice compared to control group. Administration of PIO and UD ameliorated the oxidative stress and mitochondrial damage (p < 0.05) in diabetic mice. Also increase in pain score was shown in diabetic mice that treatment with UD and PIO diminished elevation of pain score in diabetic mice. Interestingly, simultaneous administration of PIO and UD showed synergism effect in attenuation of oxidative stress and hyperglycemia. CONCLUSION: UD showed a therapeutic potential for the attenuation of oxidative stress and diabetes-induced hyperglycemia that can be considered as co-treatment in treatment of diabetic neurotoxicity.

Size-Dependent Neurotoxicity of Aluminum Oxide Particles: a Comparison Between Nano- and Micrometer Size on the Basis of Mitochondrial Oxidative Damage.

Aluminum nanoparticles (AlNPs) are among the most abundantly produced nanosized particles in the market. There is limited information about the potential harmful effects of aluminum oxide due to its particle size on human health. Considering the toxic effects of Al on brain as its target tissue, in this study, the toxicity of nanoparticles, microparticles, and ionic forms of Al on rat brain and isolated mitochondria was evaluated. Sixty male Wistar rats were divided into ten groups (six rats each), in which group I was the control, and the other groups were administered different doses of Al nanoparticles, Al microparticles (AlMP), and Al ionic forms (2, 4, and 8 mg/kg, i.p.) for 28 days. After 24 h, the animals were killed, brain tissue was separated, the mitochondrial fraction was isolated, and oxidative stress markers were measured. Also, mitochondrial function was assayed by MTT test. The results showed that all forms of Al particles induced ROS formation, lipid peroxidation, protein oxidation, glutathione depletion, mitochondrial dysfunction, and gait abnormalities in a dose-dependent manner. In addition, Al particles decreased mitochondrial membrane potential. These data indicated that oxidative stress might contribute to the toxicity effects of Al. Comparison of oxidative stress markers between all forms of Al revealed that the toxic effect of AlNP on brain tissue was substantially more than that caused by AlMP and bulk form. This study showed more neurotoxicity of AlNPs compared to other forms on brain oxidative damage that probably is due to more penetration into the brain.

The impact of silymarin on antioxidant and oxidative status in patients with ß-thalassemia major: A crossover, randomized controlled trial.

BACKGROUND & AIMS: Blood transfusion therapy is lifesaving for individuals with ß-thalassemia major (ß-TM). Iron burden following blood transfusion is the main cause of oxidative stress (OS) and organ dysfunction in these patients. The aim of this study was to evaluate the effects of silymarin on serum antioxidant and oxidative status in patients with ß-TM. METHODS: A crossover, randomized controlled trial was performed on 82 thalassemia patients. In two periods of 12 weeks, patients received 420mg silymarin (divided into three equal 140-mg daily doses) and placebo. The washout period between the two phases was two weeks. Serum malondialdehyde (MDA), protein carbonyl (CO), total antioxidant capacity (TAC), and reduced glutathione (GSH) were measured before and after both periods. RESULTS: Sixty-nine patients completed the study. Mean serum MDA and protein CO significantly decreased in all patients with ß-TM after three months of treatment with silymarin. At the end of the study, serum MDA decreased from 20.36±20.11 to 4.79±4.71µmol/l (compared to 17.81±16.05µmol/l after administration of placebo), and protein CO dropped from 0.31±0.28 to 0.11±0.09mM/l (compared to 0.24±0.17mM/l with placebo). Additional laboratory parameters (such as serum TAC and plasma GSH) were also significantly elevated after therapy with silymarin. At the end of the study, serum TAC increased in all patients from 620.7±202.64 to 971.83±328.16µmol FeSO4/l (compared to 672.22±206.88µmol FeSO4/l with placebo), and GSH increased from 46.16±41.68 to 195.35±210.98nM/l (compared to 58.52±48.95nM/l with placebo). The treatment effect of silymarin was measured using a mixed-effects model of variance analysis for changes in MDA, protein CO, TAC, and GSH, with significant effects being demonstrated for each laboratory parameter (P<0.001, P=0.002, P<0.001, and P<0.001, respectively). CONCLUSIONS: Silymarin was effective in decreasing serum OS and enhancing serum antioxidant capability in patients with ß-thalassemia major. Silymarin given as an adjuvant therapy to standard iron chelators may provide an improvement in the OS measurements obtained in these patients, with accompanying benefit.

Zinc Deficiency and Oxidative Stress Involved in Valproic Acid Induced Hepatotoxicity: Protection by Zinc and Selenium Supplementation.

Valproic acid (VPA) is an antiepileptic drug, which its usage is limited due to its hepatotoxicity. The present study was conducted to investigate the efficacy of zinc (Zn) and selenium (Se), necessary trace elements, against VPA-induced hepatotoxicity in Wistar rats. The animals were divided into five groups: control, VPA 200 mg/kg, VPA + Zn (100 mg/kg), VPA + Se (100 mg/kg), and VPA + Zn + Se. The administration of VPA for four consecutive weeks resulted in decrease in serum level of Zn in rats. Also, an increase in liver marker enzymes (ALT and AST) and also histological changes in liver tissue were shown after VPA administration. Oxidative stress was evident in VPA group by increased lipid peroxidation (LPO), protein carbonyl (PCO), glutathione (GSH) oxidation, and reducing total antioxidant capacity. Zn and Se (100 mg/kg) administration was able to protect against deterioration in liver enzyme, abrogated the histological change in liver tissue, and suppressed the increase in oxidative stress markers. Zn and combination of Zn plus Se treatment showed more protective effects than Se alone. These results imply that Zn and Se should be suggested as effective supplement products for the prevention of VPA-induced hepatotoxicity.

Antioxidant and anti-inflammatory effects of Nasturtium officinale involved in attenuation of gentamicin-induced nephrotoxicity.

BACKGROUND AND PURPOSE: Gentamicin (GM) is used against bacterial infections. The aim of our investigation was to evaluate the role of inflammation and also oxidative damage in nephrotoxic potential of GM and protective effects of Nasturtium officinale (watercress) against GM-induced nephrotoxicity in Wistar rats. MATERIAL AND METHODS: The animals were divided into eight groups: control, solvent, GM (80 mg/kg IP), GM with three doses (50, 100 and 200 mg/kg/d) of hydroalcoholic extract of watercress and one group only received high dose of extract and a group which received GM plus vitamin E for 10 consecutive days. Then, the animals were killed and kidney tissues were separated. Finally reactive oxygen species (ROS), glutathione (GSH) content, lipid peroxidation (LPO), protein carbonyl (PCO), nitric oxide (NO) and tumor necrosis factor-alpha (TNF-α) were evaluated. Also, pathological examination and measuring of blood urea nitrogen (BUN) and creatinine (Cr) were done. RESULTS: The administration of GM for 10 d resulted in an increase in kidney markers (BUN and Cr) and pathological changes in kidney tissue. Also, oxidative stress was evident in GM group by increased ROS, LPO and PCO level and GSH oxidation. Increased in inflammation process was shown by increase in NO and TNF-α. Administration of watercress extract was able to protect against deterioration in nephrotoxic markers and suppressed the increase in oxidative stress and inflammation markers. CONCLUSIONS: Our study showed the critical role of oxidative damage and inflammation in GM-induced nephrotoxicity that markedly inhibited by administration of watercress. Therefore, watercress can be suggested for prevention of GM-induced nephrotoxicity.

Melatonin can attenuate ciprofloxacin induced nephrotoxicity: Involvement of nitric oxide and TNF-α.

BACKGROUND: Ciprofloxacin is a synthetic broad-spectrum antimicrobial agent of fluoroquinolone family. The aim of our investigation was to evaluate the role of oxidative damage and inflammation in nephrotoxic potential of Ciprofloxacin and protective effects of melatonin against its nephrotoxicity in male Wistar rats. METHODS: The animals were divided into six groups: Control, ciprofloxacin (100mg/kg/day, i.p), ciprofloxacin with three doses (2.5, 5 and 10mg/kg/day) of melatonin and a group which received ciprofloxacin (100mg/kg/day) plus vitamin E (100mg/kg/day) for 8 consecutive days. 24h after last injection, the animals were euthanized and kidney tissues were separated. Finally reactive oxygen species, glutathione content, lipid peroxidation, protein carbonyl, nitric oxide and TNF-α were evaluated. Also, pathological examination and measuring of kidney biochemical markers (BUN and Cr) were done. RESULTS: The administration of ciprofloxacin for 8days resulted in significant increase (P<0.01) in kidney biomarkers (BUN and Cr) and pathological changes. Also, Oxidative stress was evident in ciprofloxacin group by significantly (p<0.001) increased reactive oxygen species, lipid peroxidation and protein carbonyl level and decreased glutathione content (p<0.001). Increased in inflammation process was shown by increase in NO and TNF-α (P<0.001). Administration of melatonin was able to protect against deterioration in nephrotoxic markers and suppressed the increase in oxidative stress and inflammatory markers. CONCLUSION: Our study showed the critical role of oxidative damage and inflammation in ciprofloxacin-induced nephrotoxicity that markedly inhibited by administration of melatonin. So, melatonin can be suggested for prevention of ciprofloxacin-induced nephrotoxicity.

Mercury exposure of gold mining workers in the northwest of Iran.

Mercury exposure is a health concern in the occupational settings like gold mining and chloralkali industries and blood and urine levels of mercury are used as exposure indicators. In this study, blood and urine concentrations of mercury were determined using hydride generation atomic absorption spectrophotometery (HGAAS) in sixteen gold miners with neuropsychiatric symptoms. The patients treated with two chelating agents, dimercaprol and D-penicillamine. The mean serum mercury levels before and after chelation therapy were 208.14 µg/L(-1) and 10.50 µg/L(-1), respectively. The mean urinary mercury levels before and after chelation therapy were 134.70 µg/L(-1) and 17.23 µg/L(-1), respectively. The results of this study showed that there are significant differences between concentration of blood and urine mercury before and after intervention (p<0.005). There were no significant differences between in the biochemistry parameters of patients before and after treatment. This study indicated that the gold miners in the northwest of Iran had been exposed to high levels of mercury vapors [Hg((0))].

Depleted uranium induces disruption of energy homeostasis and oxidative stress in isolated rat brain mitochondria.

Depleted uranium (DU) is emerging as an environmental pollutant primarily due to its military applications. Gulf War veterans with embedded DU showed cognitive disorders that suggest that the central nervous system is a target of DU. Recent evidence has suggested that DU could induce oxidative stress and mitochondrial dysfunction in brain tissue. However, the underlying mechanisms of DU toxicity in brain mitochondria are not yet well understood. Brain mitochondria were obtained using differential centrifugation and were incubated with different concentrations (50, 100 and 200 µM) of uranyl acetate (UA) as a soluble salt of U(238) for 1 h. In this research, mitochondrial ROS production, collapse of mitochondrial membrane potential and mitochondrial swelling were examined by flow cytometry following the addition of UA. Meanwhile, mitochondrial sources of ROS formation were determined using specific substrates and inhibitors. Complex II and IV activity and also the extent of lipid peroxidation and glutathione (GSH) oxidation were detected via spectroscopy. Furthermore, we investigated the concentration of ATP and ATP/ADP ratio using luciferase enzyme and cytochrome c release from mitochondria which was detected by ELISA kit. UA caused concentration-dependent elevation of succinate-linked mitochondrial ROS production, lipid peroxidation, GSH oxidation and inhibition of mitochondrial complex II. UA also induced mitochondrial permeability transition, ATP production decrease and increase in cytochrome c release. Pre-treatment with antioxidants significantly inhibited all the above mentioned toxic effects of UA. This study suggests that mitochondrial oxidative stress and impairment of oxidative phosphorylation in brain mitochondria may play a key role in DU neurotoxicity as reported in Gulf War Syndrome.

Toxicity of depleted uranium on isolated rat kidney mitochondria.

BACKGROUND: Kidney is known as the most sensitive target organ for depleted uranium (DU) toxicity in comparison to other organs. Although the oxidative stress and mitochondrial damage induced by DU has been well investigated, the precise mechanism of DU-induced nephrotoxicity has not been thoroughly recognized yet. METHODS: Kidney mitochondria were obtained using differential centrifugation from Wistar rats and mitochondrial toxicity endpoints were then determined in both in vivo and in vitro uranyl acetate (UA) exposure cases. RESULTS: Single injection of UA (0, 0.5, 1 and 2mg/kg, i.p.) caused a significant increase in blood urea nitrogen and creatinine levels. Isolated mitochondria from the UA-treated rat kidney showed a marked elevation in oxidative stress accompanied by mitochondrial membrane potential (MMP) collapse as compared to control group. Incubation of isolated kidney mitochondria with UA (50, 100 and 200µM) manifested that UA can disrupt the electron transfer chain at complex II and III that leads to induction of reactive oxygen species (ROS) formation, lipid peroxidation, and glutathione oxidation. Disturbances in oxidative phosphorylation were also demonstrated through decreased ATP concentration and ATP/ADP ratio in UA-treated mitochondria. In addition, UA induced a significant damage in mitochondrial outer membrane. Moreover, MMP collapse, mitochondrial swelling and cytochrome c release were observed following the UA treatment in isolated mitochondria. GENERAL SIGNIFICANCE: Both our in vivo and in vitro results showed that UA-induced nephrotoxicity is linked to the impairment of electron transfer chain especially at complex II and III which leads to subsequent oxidative stress.

Protective effects of fungal ß-(1→3)-D-glucan against oxidative stress cytotoxicity induced by depleted uranium in isolated rat hepatocytes.

Previous reports suggested that certain carbohydrate polymers, such as ß-(1→3)-D-glucan, may possess free radical scavenging activity. The present study examined the free radical scavenging activity of a carbohydrate polymer, ß-(1→3)-D-glucan against oxidative stress induced by depleted uranium in isolated rat hepatocytes. Addition of U (VI) (uranyl acetate) to isolated rat hepatocytes results in reactive oxygen species (ROS) formation, rapid glutathione depletion, mitochondrial membrane potential collapse and lysosomal membrane rupture before hepatocyte lysis occurred. Our results showed that quite similar to silymarin, which is a known antioxidant and radical scavenger, tiny concentration of ß-glucan (138 nM) very successfully protected the hepatocytes against cell lysis and all oxidative stress cytotoxicity endpoints caused by depleted uranium including ROS formation, glutathione depletion, decreased mitochondrial membrane potential, lysosomal membrane rupture and caspase 3 activity increase. In conclusion, our results confirmed the antioxidant and radical scavenging activity of ß-(1→3)-D-glucan and suggested this compound and silymarin as possible drug candidates for prophylaxis and treatment against depleted uranium toxic effects.

Kopetdaghins A-E, sesquiterpene derivatives from the aerial parts and the roots of Dorema kopetdaghense.

Three new sesquiterpene derivatives, kopetdaghins A-C (1-3), one known prenylated coumarin (7), and two known steroid glucosides, sitosterol 3-O-glucoside and stigmasterol 3-O-glucoside, were isolated from the aerial parts of Dorema kopetdaghense. In addition, two new sesquiterpene derivatives, kopetdaghin D (4) and kopetdaghin E (5), together with kopetdaghins A-C and one known sesquiterpene coumarin (6), were isolated from the roots of the plant. The structures of these compounds were elucidated by various 1D and 2D NMR techniques as well as high-resolution positive-ion ESIMS.