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.

Possible Curative Effects of Boric Acid and Bacillus clausii Treatments on TNBS-Induced Ulcerative Colitis in Rats.

Crohn's disease (CD) and ulcerative colitis (UC) are two chronic relapsing inflammatory bowel diseases (IBD). Although there are several treatment options available to improve the symptoms of IBD patients, there is no effective treatment that provides a definitive solution. In the present study, we aim to investigate the antioxidative/anti-inflammatory effects of oral administration of boric acid and Bacillus clausii in a rat trinitrobenzenesulfonic acid (TNBS)-induced colitis model. The effects of boric acid and B. clausii were examined in serum and colon tissues with the help of some biochemical and histological analyses. Elevated inflammation and oxidative damage were found in the blood and colon tissue samples in the TNBS-induced group according to the complete blood count (CBC), tumor necrosis factor (TNF) alpha, interleukin-35 (IL-35), malondialdehyde (MDA), glutathione peroxidase (GPx), myeloperoxidase (MPO), nitric oxide (NO), and histological findings. Particularly, the highest IL-35 level (70.09 ± 12.62 ng/mL) in the combined treatment group, highest catalase activity (5322 ± 668.1 U/mg protein) in the TNBS-induced group, and lower relative expression of inducible nitric oxide synthase in the TNBS-induced group than the control group were striking findings. According to our results, it can be concluded that boric acid showed more curative effects, even if B. clausii probiotics was partially ameliorative.

Cardiac hypertrophy caused by hyperthyroidism in rats: the role of ATF-6 and TRPC1 channels.

Hyperthyroidism influences the development of cardiac hypertrophy. Transient receptor potential canonical channels (TRPCs) and endoplasmic reticulum (ER) stress are regarded as critical pathways in cardiac hypertrophy. Hence, we aimed to identify the TRPCs associated with ER stress in hyperthyroidism-induced cardiac hypertrophy. Twenty adult Wistar albino male rats were used in the study. The control group was fed with standard food and tap water. The group with hyperthyroidism was also fed with standard rat food, along with tap water that contained 12 mg/L of thyroxine (T4) for 4 weeks. At the end of the fourth week, the serum-free triiodothyronine (T3), T4, and thyroid-stimulating hormone (TSH) levels of the groups were measured. The left ventricle of each rat was used for histochemistry, immunohistochemistry, Western blot, total antioxidant capacity (TAC), and total oxidant status (TOS) analysis. As per our results, activating transcription factor 6 (ATF-6), inositol-requiring kinase 1 (IRE-1), and TRPC1, which play a significant role in cardiac hypertrophy caused by hyperthyroidism, showed increased activation. Moreover, TOS and serum-free T3 levels increased, while TAC and TSH levels decreased. With the help of the literature review in our study, we could, for the first time, indicate that the increased activation of ATF-6, IRE-1, and TRPC1-induced deterioration of the Ca2+ ion balance leads to hypertrophy in hyperthyroidism due to heart failure.

Investigation of the effect of hyperthyroidism on endoplasmic reticulum stress and tran- sient receptor potential canonical 1 channel in the kidney

Background/aim: Hyperthyroidism is associated with results in increased glomerular filtration rate as well as increased renin-angio- tensin-aldosterone activation. The disturbance of Ca2+ homeostasis in the endoplasmic reticulum (ER) is associated with many diseases, including diabetic nephropathy and hyperthyroidism. Transient receptor potential canonical 1 (TRPC1) channel is the first cloned TRPC family protein. Although it is expressed in many places in the kidney, its function is uncertain. TRPC1 is involved in regulating Ca2+ homeostasis, and its upregulation increases ER Ca2+ level, activates the unfolded protein response, which leads to cellular damage in the kidney. This study investigated the role of TRPC1 in the kidneys of hyperthyroid rats in terms of ER stress markers that are gluco- se-regulated protein 78 (GRP78), activating transcription factor 6 (ATF6), (protein kinase R (PKR)-like endoplasmic reticulum kinase) (PERK), Inositol-requiring enzyme 1 (IRE1). Materials and methods: Twenty male rats were assigned into control and hyperthyroid groups (n = 10). Hyperthyroidism was induced by adding 12 mg/L thyroxine into the drinking water of rats for 4 weeks. The serum-free T3 and T4 (fT3, fT4), TSH, blood urea nitrogen (BUN), and creatinine levels were measured. The histochemical analysis of kidney sections for morphological changes and also im- munohistochemical and western blot analysis of kidney sections were performed for GRP78, ATF6, PERK, IRE1, TRPC1 antibodies. Results: TSH, BUN, and creatinine levels decreased while fT3 and fT4 levels increased in the hyperthyroid rat. The morphologic analy- sis resulted in the capillary basal membrane thickening in glomeruli and also western blot, and immunohistochemical results showed an increase in TRPC1, GRP78, and ATF6 in the hyperthyroid rat (p < 0.05). Conclusion: In conclusion, in our study, we showed for the first time that the relationship between ER stress and TRPC1, and their increased expression caused renal damage in hyperthyroid rats.

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.

Evaluation of the Neuroprotective Role of Boric Acid in Preventing Traumatic Brain Injury-Mediated Oxidative Stress.

AIM: Oxidative stress(OS) and lipid peroxidation(LP) occur in a cell due to irreversible damage resulting from incidents such as traumatic brain injury(TBI). The aim of our study was to investigate the possible neuroprotective effect of boric acid (BA) by examining the changes in catalase (CAT) activity and levels of CAT and malondialdehyde (MDA) in brain tissues from rats with closed head trauma. MATERIAL AND METHODS: The study consisted of three groups: control ,TBI and TBI + BA. Animals in the control and TBI groups received saline ,while animals in the TBI + BA group received BA through daily oral gavage, for 14 days prior to TBI was performed using the modified Marmarou impact acceleration model . After 24 hours,animals were euthanized and brain tissue obtained to measure the levels of MDA and to assess the activity of CAT. RESULTS: MDA levels and CAT activity were significantly higher in the TBI group versus the control group. However, they were significantly lower in the TBI + BA group compared to TBI alone. Similarly, edema and necrotic neurons were observed in the TBI group, but not in the control or TBI + BA groups. CONCLUSION: Based on biochemical and histopathological evidence, we determined that TBI induced LP and OS were inhibited by pre-treatment with BA.

Mirtazapine suppresses sterile inflammation through NLRP3-inflammasome in diabetic rat kidney.

AIM: The aim of this study was to investigate the effects of mirtazapine, which is anti-oxidative and antidepressant agent, on the kidney damage caused by diabetes mellitus. MATERIALS AND METHODS: The rats were randomly divided into three groups (n = 7 animals in each group). The group I rats served as control and they received 0.1 mol/L of citric acid buffer (pH = 4.5) as vehicle. The rats in the group II (DM group) and III (DM + Mirtazapine-treated group) were treated intraperitoneally with a single dose of 55 mg/kg streptozotocin dissolved in 0.1 mol/L of citric acid buffer. Group III rats were also received 20 mg/kg/day of mirtazapine for 2 weeks. At the end of the experiment, the rats were sacrificed. Then, the kidneys were excised and prepared for microscopical examination. caspase-1 and NLRP3 proteins were examined using immunohistochemistry and western blotting. The TUNEL assay for apoptosis and ELISA assay for IL-1ß were performed. RESULTS: Histological examination showed that mirtazapine administration has an ameliorative effect on DM-induced kidney damage. Immunohistochemical and western blot analyses showed that NLRP3 and caspase-1 expressions were increased in the DM group according to the control group and the mirtazapine administration decreased these expressions. The intraglomerular and tubular TUNEL-positive cells were numerous in the DM group compared to the mirtazapine-treated group. The level of IL-1ß was highest in the DM group, and decreased significantly in the mirtazapine-treated group. CONCLUSION: In this study, 20 mg/kg/day mirtazapine administration for 2 weeks reduced NLRP3 and caspase-1 expressions and IL-1ß level in the diabetic rat kidneys. These results suggesting that mirtazapine may be useful in the treatment of DM and other metabolic diseases. Advanced molecular studies are needed to elucidate the exact effects of mirtazapine on NLRP3 inflammasome.

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.

Effects of Carnosine (Beta-Alanyl-L-Histidine) in an Experimental Rat Model of Acute Kidney Injury Due to Septic Shock.

BACKGROUND Acute kidney injury (AKI) secondary to sepsis is a major cause of morbidity and mortality in the human intensive care unit (ICU). Kidney function and the histological findings of AKI were investigated in an experimental rat model with sepsis induced by cecal ligation and puncture (CLP) and compared with and without treatment with carnosine (beta-alanyl-L-histidine). MATERIAL AND METHODS Twenty-four Sprague-Dawley rats were randomly divided into three groups consisting eight rats in each: Group 1 - control; Group 2 - septic shock; and Group 3 - septic shock treated with carnosine. Femoral vein and artery catheterization were applied in all rats. Rats in Group 1 underwent laparotomy and catheterization. The other two groups with septic shock underwent laparotomy, CLP, catheterization, and bladder cannulation. Rats in Group 3 received an intraperitoneal (IP) injection of 250 mg/kg carnosine, 60 min following CLP. Rats were monitored for blood pressure, pulse rate, and body temperature to assess responses to postoperative sepsis, and 10 mL/kg saline replacement was administered. Twenty-four hours following CLP, rats were sacrificed, and blood and renal tissue samples were collected. RESULTS Statistically significant improvements were observed in kidney function, tissue and serum malondialdehyde levels, routine blood values, biochemical indices, and in histopathological findings in rats in Group 3 who were treated with carnosine, compared with Group 2 exposed to septic shock without carnosine treatment. CONCLUSIONS Carnosine (beta-alanyl-L-histidine) has been shown to have beneficial effects in reducing AKI due to septic shock in a rat model of septicemia.

Resveratrol reduces IL-6 and VEGF secretion from co-cultured A549 lung cancer cells and adipose-derived mesenchymal stem cells.

Stem cell therapies are important treatment methodologies used in many areas of experimental or clinical medicine. In recent studies of cancer models, Mesenchymal stem cells (MSCs) suppressed the growth of cancer cells. However, also in some studies, stem cell treatments have been shown to induce cancer formation, increase tumor volume, induce the formation of new vessels, and lead to cancer invasion. The presence of MSC-secreted cytokines and their effects on cancer cells limits the reliability of MSC-based treatments. Resveratrol (trans-3,5,4'-trihydroxystilbene), an antioxidant found in red wine, has been shown to have therapeutic effects against several cancers. The aim of this study was to co-culture MSCs with A549 cancer cells to suppress the release of cancer-promoting cytokines from MSCs and to increase the applicability and reliability of stem cell therapies with resveratrol. MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) and neutral red cell viability assays were used to find safety dose of resveratrol. The MSCs secreted the cytokines IL-6 and VEGF, and the effect of resveratrol on these cytokines was analyzed by ELISA and western blot analysis of conditioned medium. One µM of resveratrol was found to be the safety dose for the A549 cancer cells and MSCs. We observed the highest release of IL-6 and VEGF from the co-cultured A549 cells and MSCs, and resveratrol was found to significantly decrease the release of these cytokines. Our study suggests that resveratrol exerts a positive effect on the release of cytokines. The safety dose of resveratrol can be administered together with stem cells during stem cell treatment.