Vitamin A could be a Therapeutic Agent in Ischemia/Reperfusion Induced Kidney Injury / La vitamina A podría ser un agente terapéutico en la lesión renal inducida por isquemia/reperfusión

ABSTRACT Introduction: Renal ischemia (I) could develop due to decreased or ceased blood flow to the kidney in some clinical conditions such as shock, sepsis, and kidney transplantation. The re-supply of blood to the kidney is called reperfusion (R). Ischemia and reperfusion periods can cause severe kidney damage. Objectives: When we examined the I/R molecular progression, antioxidant molecules such as vitamin A seem promising treatment agents. This study aimed to investigate the effects of vitamin A on renal I/R injury. Material and Methods: In the study, 40 Sprague-Dawley male rats were divided into five groups (n=8): the control group, only I/R, I/R+1000, I/R+3000, and I/R+9000 IU/kg of Vitamin A groups. Vitamin A was administrated to each group for seven days via oral gavage. Blood and kidney tissue samples were collected at the end of the experiment. We took blood samples for Superoxide dismutase (SOD), malondialdehyde (MDA), catalase (CAT), blood urea nitrogen (BUN), and creatinine (Cr) levels, and determined their values. The tissue samples were stained with hematoxylin/eosin to examine the renal changes histopathologically and stereologically under a light microscope. Results: Histopathological changes caused by I/R were decreased with vitamin A administration in a dose-dependent manner (p<0.05). Vitamin A administration decreased MDA levels and increased SOD and CAT activities (p<0.05). The most effective dose among treatment groups was 9000 IU/kg. There was no significant difference between the controls and all other groups regarding BUN and Cr concentrations. Conclusions: Consequently, administration of vitamin A after renal I/R reduced the histological damage and ameliorated the antioxidant state. These results showed that vitamin A could be a promising agent in treating I/R-induced acute kidney injury.

RESUMEN Introducción: La isquemia renal (I) puede desarrollarse debido a la disminución o interrupción del flujo sanguíneo al riñón en algunas condiciones clínicas como shock, sepsis y trasplante renal. El reabastecimiento de sangre al riñón se denomina reperfusión (R). Tanto la isquemia como los períodos de reperfusión pueden causar graves daños renales. Objetivos: Cuando examinamos la progresión molecular I/R, las moléculas antioxidantes como la vitamina A parecen agentes de tratamiento prometedores. El objetivo de este estudio fue investigar los efectos de la vitamina A sobre la lesión renal I/R. Material y Métodos: En el estudio, 40 ratas macho Sprague-Dawley se dividieron en 5 grupos (n=8) como: control, solo I/R, I/R+1000, I/R+3000 e I/R+9000 UI/kg de la Vitamina A. La vitamina A se administró a cada grupo durante 7 días por vía oral forzada. Al final del experimento se recolectaron muestras de sangre y tejido del riñón. A partir de muestras de sangre se determinaron los niveles de superóxido dismutasa (SOD), malondialdehído (MDA), catalasa (CAT), nitrógeno ureico en sangre (BUN) y creatinina (Cr). Las muestras de tejido se tiñeron con hematoxilina/eosina y los cambios en la histología renal se examinaron histopatológicamente y estereológicamente al microscopio de luz. Resultados: Los cambios histopatológicos causados por I/R disminuyeron con la administración de la vitamina A de manera dependiente de la dosis (p<0,05). La administración de la vitamina A disminuyó los niveles de MDA, aumentó las actividades de SOD y CAT (p<0,05). La dosis más eficaz entre los grupos del tratamiento fue de 9000 UI/kg. No hubo una diferencia significativa entre el grupo control y todos los demás grupos con respecto a las concentraciones de BUN y Cr. Conclusiones: Consiguientemente, la administración de la vitamina A, después de I/R renal, redujo el daño histológico y mejoró el estado antioxidante. Estos resultados mostraron que la vitamina A puede ser un agente promisorio en el tratamiento de la lesión renal aguda (LRA) inducida por I/R.

Naringenin Ameliorate Carbon Tetrachloride-Induced Hepatic Damage Through Inhibition of Endoplasmic Reticulum Stress and Autophagy in Rats.

Hepatic fibrosis emerges upon exposure of liver to various chemicals and if not treated, it develops various diseases such as cirrhosis and cancer. Carbon tetrachloride (CCl4) is a widely used toxin in animal models to develop hepatic fibrosis. Accumulation of unfolded proteins in cells causes stress in the endoplasmic reticulum (ER) and various mechanisms are involved in the cell to reduce the damage caused by these unfolding proteins. The most well known of these is the unfolded protein response. Further, autophagy works to remove these proteins if the damage cannot be repaired and is permanent. In our study, we investigated the effects of naringenin (NRG), a flavanon abundant in citrus fruits, on ER stress and autophagy in CCl4-injured rat liver. The animals were given 0.2 mL/kg of CCl4 for 10 days and treatment group was administered 100 mg/kg of NRG for 14 days. Histopathological examination was performed to show liver damage and to determine the therapeutic properties of the active substance. Transmission electron microscopy (TEM) analysis was carried out to establish cell level damage and effect of treatment. In addition, levels of ER stress and autophagy markers of liver were measured. According to our findings, TEM demonstrated positive effect of NRG and histological examinations reported ameliorative effects. In addition, NRG reduced levels of ER stress markers and inhibited autophagy significantly compared to CCl4-treated group. As a result, NRG significantly reduced damage in hepatocytes and provided a significant amelioration.

Propolis Protects Endotoxin Induced Acute Lung and Liver Inflammation Through Attenuating Inflammatory Responses and Oxidative Stress.

Propolis is a natural bee product, and it has many effects, including antioxidant, anti-inflammatory, antihepatotoxic, and anticancer activity. In this study, we aimed to explore the potential in vivo anti-inflammatory, antioxidant, and antiapoptotic properties of propolis extract on lipopolysaccharide (LPS)-induced inflammation in rats. Forty-two, 3- to 4-month-old male Sprague Dawley rats were used in six groups. LPS (1 mg/kg) was administered intraperitoneally to rats in inflammation, inflammation + propolis30, and inflammation+propolis90 groups. Thirty milligram/kilogram and 90 mg/kg of propolis were given orally 24 h after LPS injection. After the determination of the inflammation in lung and liver tissues by 18F-fluoro-deoxy-d-glucose-positron emission tomography (18FDG-PET), samples were collected. The levels of malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), nitric oxide (NO), and DNA fragmentation were determined. The decrease of MDA levels in inflammation + propolis30 and inflammation + propolis90 groups was determined compared to the inflammation group in lung and liver tissues. The increase of SOD% inhibition in inflammation + propolis90 group was determined in liver, lung, and hemolysate compared to the inflammation group. Increased CAT activities in inflammation + propolis30 and inflammation + propolis90 groups were observed in liver tissue and hemolysate compared to inflammation group. In lung tissue, NO levels were lower in inflammation group compared to the control group, but DNA fragmentation levels were higher. 18F-FDG uptake of tissues in inflammation + propolis30 and inflammation + propolis90 groups was decreased compared to the inflammation group. In conclusion, the data of this study indicate that the propolis application may serve as a potential approach for treating inflammatory diseases through the effect of reducing inflammation and free oxygen radical production.

Posttreatment Effects of Olea Europaea L. Leaf Extract on Carbon Tetrachloride-Induced Liver Injury and Oxidative Stress in Rats.

The aim of this study is to examine the therapeutic effects of Olea europaea L. leaf extract on carbon tetrachloride (CCl4)-induced liver damage in rats. In the experiments, 3- to 4-month-old 28 male Sprague-Dawley rats were divided into four groups: control, O. europaea leaf extract, CCl4, and curative. The CCl4 and curative groups received CCl4 (0.2 mL/kg) intraperitoneally for 10 days to form hepatic injury. O. europaea (80 mg/kg) leaf extract was given orally to the curative group dissolved in distilled water the following 14 days. Hepatic and antioxidant enzyme levels, p53, caspase 3, lipid peroxidation marker malondialdehyde (MDA), and also DNA fragmentation levels were determined to establish oxidative stress in hepatic cell damage and its consequences. After formation of liver damage, oral administration of the O. europaea significantly reduced CCl4-induced elevations of serum alkaline phosphatase, aspartate aminotransferase and alanine aminotransferase levels (P < .001), MDA levels of both blood (P < .001) and liver tissues (P < .001), DNA fragmentation (P < .001), p53 (P < .001), and caspase 3 (P < .001) levels of liver tissues. Also this administration in curative group significantly increased CCl4-induced reductions of superoxide dismutase (SOD) (P < .001) and catalase (CAT) (P < .001) activity of blood samples and decreased SOD (P < .001) and CAT (P < .05) activity observed in liver tissue curative groups compared with CCl4 curative group. In CCl4 group, liver tissue samples exhibited remarkable damage because of CCl4 and reduction of these damages were observed in the curative group. Our results showed that O. europaea leaf extract was effective in reducing hepatic damage caused by CCl4 by reducing lipid peroxidation, regulating antioxidant enzymes, and minimizing DNA damage.

The Anti-Inflammatory and Antioxidant Effects of Salvia officinalis on Lipopolysaccharide-Induced Inflammation in Rats.

Salvia officinalis, which has a high phenolic acid and flavonoid content, is a powerful antioxidant and anti-inflammatory herb. Inflammation plays an important role in the pathophysiology of many diseases and could cause damage by means of oxidative stress. The aim of this study was to investigate the anti-inflammatory and antioxidant activity of S. officinalis formed lipopolysaccharide (LPS)-induced experimental inflammation model. Four- to five-month-old 42 female Wistar albino rats were divided into six groups. Three groups were administered intraperitoneally 1 mg/kg LPS. Twenty-four hours after injection of LPS, 10 and 30 mg/kg S. officinalis extract were given orally to treatment groups. Pulmonary and hepatic 18F-fluoro-deoxy-D-glucose (18F-FDG) uptake was calculated to determine the status of inflammation by 18F-fluoro-deoxy-D-glucose-positron emission tomography (18FDG-PET) scan. Antioxidant enzyme activities and nitric oxide (NO) and malondialdehyde (MDA) levels were determined. Nuclear factor-kappa B (NF-κB) and tumor necrosis factor-alpha (TNF-α) levels were also detected in serum. As a result, lung and liver 18F-FDG uptake was found to be higher in the inflammation group than control group. MDA levels in erythrocyte and all tissue samples (liver, lung, and kidney) were found to be significantly higher compared to treatment groups. Superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase activities of the inflammation group in the liver, lung, kidney tissues, and erythrocyte SOD and CAT activities were determined to significantly lower than groups treated with S. officinalis. Increased NO, NF-κB, and TNF-α levels were found in the inflammation group. S. officinalis has been observed to have useful effects on LPS-induced inflammation and oxidative stress in rats.

miRSNPs of miR1274 and miR3202 Genes that Target MeCP2 and DNMT3b Are Associated with Lung Cancer Risk: A Study Conducted on MassARRAY Genotyping.

Genetic variants of miRNAs that target DNMTs and MBDs involved in DNA methylation were scanned with current databases, and 35 miRSNPs in 22 miRNA genes were identified. The aim of the study was to determine the association between these variants of miRNA genes and lung cancer (LC). DNA samples were isolated from blood samples and genotyped using a Sequenom MassARRAY System. An association between the rs188912830 gene variant of miR3202 that targets the MeCP2 protein and LC was indicated in both subtypes. The presence of the C-allele in patients with LC and its subtypes was significantly lower, and the absence of the C-allele was determined to increase the risk of LC by 7,429-times compared to the presence (p=0,010). The rs318039 gene variant of miR1274 that targets DNMT3b was found to be associated with LC subtypes. When allele distributions were compared, the numbers of individuals with the C-allele were significantly lower in the NSCLC and SCLC groups. No significant associations were found for the rs72563729 variant of the miR200b gene that targets DNMT3a or for the rs145416750 variant of the miR513c gene that targets TRDMT1. The other 33 variants were found to be ancestral genotypes. Consequently, rs188912830 and rs318039 variations were associated with LC subtypes. Importantly, this study is the first to indicate the functional characterisation of miRSNPs of genes that target DNA methylation.

Protective effects of the nuclear factor kappa B inhibitor pyrrolidine dithiocarbamate on experimental testicular torsion and detorsion injury.

Testicular torsion results with the damage of the testis and it is a surgical emergency. Pyrrolidine dithiocarbamate (PDTC) is a low-molecular-weight antioxidant and potent inhibitor of nuclear factor kappa B (NF-κB) activation. In this study, we aimed to investigate the effects of PDTC to testicular torsion-detorsion (T/D) injury. Forty adult male Sprague-Dawley rats were separated into four groups. A sham operation was performed in group I. In group II, torsion is performed 2 hours by 720 degree extravaginally testis. In group III, 4 h reperfusion of the testis was performed after 2 h of testicular torsion. In group IV, after performing the same surgical procedures as in group III, PDTC (100 mg/kg, intravenous's) was administered before 30 min of detorsion. The testes tissue malondialdehyde (MDA), superoxide dismutase (SOD) catalase (CAT) level was evaluated. Histological evaluations were performed after hematoxylin and eosin staining. Testicular tissue MDA levels were the highest in the T/D groups compared with treatment group. Administration of PDTC prevented a further increase in MDA levels. Significant decrease occurred in CAT and SOD levels in treatment group compared with the control group. The rats in the treatment group had normal testicular architecture. The results suggest that PDTC can be a potential protective agent for preventing the biochemical and histological changes related to oxidative stress in testicular injury caused by testis torsion.

Protective effects of N(G)-nitro-L-arginine methyl ester and metallothioneins on excess nitric oxide toxicity in trinitrobenzene sulfonic acid-induced rat colitis.

OBJECTIVE: To evaluate the protective effects of N(G)-nitro-L-arginine methyl ester (L-NAME) and metallothioneins on excess nitric oxide toxicity in trinitrobenzene sulfonic acid (TNBS)-induced rat colitis. STUDY DESIGN: In this study, 70 rats were assigned to 7 groups of controls, and colitis was induced with 120 mg/kg TNBS, 35 mg/kg L-NAME, and 1 and 2 mg/kg metallothionein 1 (MT1) and metallothionein 2 (MT2), respectively. A day after the administration of TNBS, L-NAME, MT1 and MT2 were given intraperitoneally for 3 days to the experimental groups. After the administration of TNBS, dissections of the rats in the L-NAME, MT1 and MT2 groups were performed at 3-day periods under ether anesthesia, and whole blood, bone marrow and colon were obtained. RESULTS: On the third day, red and white blood cell values were increased, while platelet and bone marrow granule cells decreased in the L-NAME- and TNBS-induced group. On the third day, all the blood values increased in MT1 (1 and 2 mg/kg) and MT2 (1 and 2 mg/kg) in the TNBS-administered groups. Histologic findings were macroscopic score, ulcer, loss of mucous cells, crypt abscess, inflammatory cyst, mucosa atrophy, edema, vascular dilatation and induced nitric oxide synthetase, which increased in the descending colon in the colitis rats, while it was decreased rats given L-NAME, MT1 and MT2 administration. CONCLUSION: The results suggest that MT1 and MT2 are more effective in protecting against the toxic effects of excess nitric oxide as compared with L-NAME in the colitis rats.

The effects of levetiracetam on urinary 15f-2t-isoprostane levels in epileptic patients.

PURPOSE: We aimed to investigate the effects of levetiracetam on oxidative stress which is one of the new antiepileptic drugs in epileptic patients. METHODS: The study consisted of 21 patients with cryptogenic partial epilepsy. We determined the urinary 15F-2t-isoprostane levels of the 30 patients which is a marker of oxidative stress. Morning urine samples were collected from the patients before beginning LEV and after 3 months treatment. Of these patients 9 were excluded from the study that had seizure history in the last 1 month. Urinary levels of 15-F2t-isoprostane determined by ELISA initially and after 3 months treatment for each patient. RESULTS: Mean age of the 21 patients was 29.6, of these 11 were females and 10 males. Mean urinary 15F-2t-isoprostane level of the patients was 876 ± 447 ng/mg Cr before the treatment of LEV. After 3 months treatment the mean 15F-2t-isoprostane level of the patients was 1560 ± 630. The patients had significantly higher levels of urinary 15F-2t-isoprostane when compared with initial levels (p = 0.025). CONCLUSION: Our results showed the increase of urinary 15F-2t-isoprostane levels in epileptic patients whom were treated with LEV which may indicate that LEV induces the oxidative stress in epileptic patients.

The protective effects of vitamin E on urinary bladder apoptosis and oxidative stress in streptozotocin-induced diabetic rats.

OBJECTIVES: To determine whether vitamin E has protective effects or not on streptozotocin-induced diabetic rats in diabetic urinary bladder dysfunction, with interrelationships between oxidative stress and apoptosis. METHODS: Thirty-two Wistar albino male rats were divided into 4 groups. Group A (n = 8), control; group B (n = 8), diabetic control; group C (n = 8), control + vitamin E; and group D (n = 8), diabetic + vitamin E. Vitamin E was injected 40 mg/kg every other day intraperitoneally for 2 weeks. In the diabetic groups, diabetes was induced by a single intraperitoneal injection of 65 mg/kg of streptozotocin. Apoptosis studies were performed using apoptosis detection kit and the TUNEL (TdT-mediated dUTP nick-end labeling) technique. The levels of glucose, malondialdehyde (MDA), superoxide dismutase, catalase, and glutathione peroxidase were detected in hemolysate. RESULTS: It was observed that apoptosis number in urothelial cells of the bladder in diabetic rats increased significantly compared with control and decreased after vitamin E treatment. MDA levels of the diabetic group were significantly higher than those on the control and vitamin E groups. Diabetic + vitamin E group had significantly increased MDA levels compared with control group, although these values were lower than those in the diabetic group. All enzyme activities of the vitamin E group did not differ compared with the control group. In diabetic + vitamin E group, superoxide dismutase and glutathione peroxidase activities were similar to controls. Catalase activity of the diabetic + vitamin E group decreased significantly compared with control, although it was higher than that in the diabetic group. CONCLUSIONS: Our study revealed that vitamin E decreases apoptosis and may be protective for uroepithelial cells of diabetic bladder.

The protective effects of demethoxyviridine and 1-alpha-hydroxy-demethoxyviridine in the livers of male rats treated with diethylnitrosamine and 2-acetylaminflourene.

OBJECTIVE: To determine the protective effects of a fungal metabolite of demethoxyviridine (DMV) and its derivative, 1-alpha-hydroxy-DMV in the livers of 2-month-old male Spraque-Dawley rats treated with diethylnitrosamine (DEN) and 2-acetylaminflourene (2-AAF). METHODS: This study was performed in the Department of Medical Biology, Faculty of Medicine, Eskisehir Osmangazi University, Eskisehir, Turkey from May 2006. Animals were divided into 10 groups. Those were the control, olive oil, dimethyl sulfoxide (DMSO), DMV, 1-alpha-hydroxy-DMV, DEN, 2-AAF, DEN+2-AAF, DEN+2-AAF+DMV, and DEN+2-AAF+1-alpha-hydroxy-DMV-treated animal groups. The liver microsomes were prepared from rats and the levels of expression of cytochrome P450 1A2 (CYP1A2) enzymes were determined with western blot technique. The liver tissue slides were evaluated histopathologically with hematoxylin and eosin staining and immunohistochemically for Harvey-retrovirus associated DNA sequences (Ha-Ras), glutathione S- transferase (GST-p), and connexion-32 (Cx32) proteins. RESULTS: Notably, there were no appreciable differences in CYP1A2 level among control, olive oil, and DMSO-treated animals. The CYP1A2 level was significantly decreased in 2-AAF, DEN+2-AAF, DEN, DEN+2-AAF+DMV, DEN+2-AAF+1-alpha-hydroxy-DMV, 1-alpha-hydroxy-DMV, and DMV-treated animals as compared to the control. Most prenoplastic focus was found in DEN+2-AAF treated group. CONCLUSION: Demethoxyviridine and 1-alpha-hidroksi-DMV had protective effect in the livers of DEN, 2-AAF and DEN+2-AAF induced rats.