Protective role of aminoguanidine on gentamicin-induced acute renal failure in rats

Protective effects of pioglitazone in renal ischemia-reperfusion injury (RIRI): focus on oxidative stress and inflammation

BACKGROUND

Renal ischemia-reperfusion injury (RIRI) is a critical phenomenon that compromises renal function and is the most serious health concern related to acute kidney injury (AKI). Pioglitazone (Pio) is a known agonist of peroxisome proliferator-activated receptor-gamma (PPAR-γ). PPAR-γ is a nuclear receptor that regulates genes involved in inflammation, metabolism, and cellular differentiation. Activation of PPAR-γ is associated with antiinflammatory and antioxidant effects, which are relevant to the pathophysiology of RIRI. This study aimed to investigate the protective effects of Pio in RIRI, focusing on oxidative stress and inflammation.

METHODS

We conducted a comprehensive literature search using electronic databases, including PubMed, ScienceDirect, Web of Science, Scopus, and Google Scholar.

RESULTS

The results of this study demonstrated that Pio has antioxidant, anti-inflammatory, and anti-apoptotic activities that counteract the consequences of RIRI. The study also discussed the underlying mechanisms, including the modulation of various pathways such as TNF-α, NF-κB signaling systems, STAT3 pathway, KIM-1 and NGAL pathways, AMPK phosphorylation, and autophagy flux. Additionally, the study presented a summary of various animal studies that support the potential protective effects of Pio in RIRI.

CONCLUSION

Our findings suggest that Pio could protect the kidneys from RIRI by improving antioxidant capacity and decreasing inflammation. Therefore, these findings support the potential of Pio as a therapeutic strategy for preventing RIRI in different clinical conditions.

Eucalyptol regulates Nrf2 and NF-kB signaling and alleviates gentamicin-induced kidney injury in rats by downregulating oxidative stress, oxidative DNA damage, inflammation, and apoptosis

Gentamicin, an aminoglycoside antibiotic, is nowadays widely used in the treatment of gram-negative microorganisms. The antimicrobial, anti-inflammatory, and antioxidant activities of eucalyptol, a type of saturated monoterpene, have been reported in many studies. The aim of this study was to examine the possible effects of eucalyptol on gentamicin-induced renal toxicity. A total of 32 rats were divided into 4 groups; Control (C), Eucalyptol (EUC), Gentamicin (GEN), and Gentamicin + Eucalyptol (GEN + EUC). In order to induce renal toxicity, 100 mg/kg gentamicin was administered intraperitoneally (i.p.) for 10 consecutive days in the GEN and GEN + EUC groups. EUC and GEN + EUC groups were given 100 mg/kg orally of eucalyptol for 10 consecutive days. Afterwards, rats were euthanized and samples were taken and subjected to histopathological, biochemical, immunohistochemical, and real-time PCR examinations. The blood urea nitrogen (BUN) and creatinine (CRE) levels were significantly decreased in the GEN + EUC group (0.76 and 0.69-fold, respectively) compared to the GEN group. The glutathione peroxidase (GPx) and catalase (CAT) activities were significantly increased in the GEN + EUC group (1.35 and 2.67-fold, respectively) compared to the GEN group. In GEN group, Nuclear factor kappa B (NF-kB), Interleukin 1-beta (IL-1β), Inducible nitric oxide synthase (iNOS), Tumor necrosis factor-α (TNF-α), Caspase-3, 8-Hydroxy-2'-deoxyguanosine (8-OHdG) and Nuclear factor erythroid 2-related factor (Nrf2) expression levels were found to be quite irregular. GEN + EUC group decreased the expressions of NF-kB, IL-1β, iNOS, TNF-α, Caspase-3, and 8-OHdG (0.55, 0.67, 0.54, 0.54, 0.63 and 0.67-fold, respectively), while it caused increased expression of Nrf2 (3.1 fold). In addition, eucalyptol treatment ameliorated the histopathological changes that occurred with gentamicin. The results of our study show that eucalyptol has anti-inflammatory, antioxidative, antiapoptotic, nephroprotective, and curative effects on gentamicin-induced nephrotoxicity.

Protective Effect of Neutral Electrolyzed Saline on Gentamicin-Induced Nephrotoxicity: Evaluation of Histopathologic Parameters in a Murine Model

Background and Objectives: Gentamicin (GM) is a nephrotoxic aminoglycoside. Neutral electrolyzed saline (SES) is a compound with anti-inflammatory, antioxidant, and immunomodulatory properties. The objective of the present study was to evaluate whether kidney damage by GM can be prevented and/or reversed through the administration of SES. Materials and Methods: The study was carried out as a prospective, single-blind, five-arm, parallel-group, randomized, preclinical trial. The nephrotoxicity model was established in male BALB/c mice by administering GM at a dose of 100 mg/kg/day intraperitoneally for 30 days, concomitantly administering (+) SES or placebo (physiologic saline solution), and then administering SES for another 30 days after the initial 30 days of GM plus SES or placebo. At the end of the test, the mice were euthanized, and renal tissues were evaluated histopathologically. Results: The GM + placebo group showed significant tubular injury, interstitial fibrosis, and increased interstitial infiltrate of inflammatory cells compared with the group without GM. Tubular injury and interstitial fibrosis were lower in the groups that received concomitant GM + SES compared with the GM + placebo group. SES administration for 30 days after the GM administration periods (GM + placebo and GM + SES for 30 days) did not reduce nephrotoxicity. Conclusions: Intraperitoneal administration of SES prevents gentamicin-induced histologic nephrotoxicity when administered concomitantly, but it cannot reverse the damage when administered later.

Biochemical interaction of pyrvinium in gentamicin-induced acute kidney injury by modulating calcium dyshomeostasis and mitochondrial dysfunction

Acute kidney injury (AKI) has a poor clinical prognosis and increases the risk of chronic kidney failure (CKD). It is a common complication of organ failure in hospitalised patients (10-15% of all hospitalizations) and in intensive care unit (ICU) patients, with an incidence of up to 50%. Concerning ICU, AKI has a mortality rate ranging from 27% to 35%, rising to 60%-65% when dialysis is needed, with roughly 5%-20% of survivors requiring dialysis on discharge. AKI is believed to cause over 7 million deaths per year worldwide. Currently, there is no treatment for AKI or its progression to CKD. When activated by AKI, numerous pathways have been suggested as possible contributors to CKD progression. Wnt/β-catenin is a crucial regulator of kidney development that increases following the injury. Despite the overwhelming evidence that Wnt/β-catenin promotes AKI, tubulointerstitial fibrosis, a hallmark of CKD progression, is also promoted by this pathway. The therapeutic potential of Wnt/β-catenin in the treatment of AKI and the progression from AKI to CKD is being studied. This hypothesis aims to determine whether the Wnt/β-catenin inhibitor pyrvinium has a beneficial effect on the renal dysfunction and damage caused by Gentamicin.

Nephroprotective Potential of a Standardized Extract of Bambusa arundinacea: In Vitro and In Vivo Studies

Bambusa arundinacea (RETZ.) Willd. is distributed in tropical regions of Pakistan, India, and China. It has been used for a long time as a folk remedy for cirrhosis, urinary tract ailments, and various other abdominal cavity disorders. It has antioxidant, free-radical-scavenging, and anti-inflammatory effects. The aims and objectives of this study were to validate the folkloric uses of Bambusa arundinacea and to evaluate its nephroprotective potential on scientific grounds. Gentamycin (G.M, 40 mg/kg) was used to induce nephrotoxicity in the animal model. Two doses of the methanolic extract of Bambusa arundinacea (MEBA; 300 and 500 mg/kg) were utilized in addition to silymarin (200 mg/kg/d). Treatments were administered once daily for 14 days. After 14 days, the blood was collected and the kidneys were removed. The antioxidant potential of the standardized MEBA was evaluated using the total phenolic content, the total flavonoid content, and the DPPH scavenging activity. The plant extract was rich with flavonoid content. The DPPH scavenging activity was 65% as compared to butylated hydroxy toluene (96%), with IC₅₀ values 31.65 and 7.80 μg/mL, respectively. The phytochemical analysis was performed using HPLC, and MEBA was found to contain various phytoconstituents such as quercetin, caffeic acid, vanillic acid, gallic acid, chlorogenic acid, and cinnamic acid. Antioxidant enzymes such as superoxide dismutase and catalase were assayed, and MEBA exhibited significantly improved CAT and SOD levels. The levels of renal function markers such as serum creatinine, serum urea, blood urea nitrogen, serum urea, and serum uric acid levels also evaluated, and a significant retrieval was found in a dose-dependent fashion. Good improvement was also made in various hematological parameters. Statistical analysis was done using analysis of variance to determine the significance of differences among the data. In conclusion, the standardized methanolic extract of Bambusa arundinacea was able to alleviate gentamicin-induced nephrotoxicity by enhancing the antioxidant defensive mechanisms of renal tubular cells.

Aminoguanidine Prevents the Oxidative Stress, Inhibiting Elements of Inflammation, Endothelial Activation, Mesenchymal Markers, and Confers a Renoprotective Effect in Renal Ischemia and Reperfusion Injury

Oxidative stress produces macromolecules dysfunction and cellular damage. Renal ischemia-reperfusion injury (IRI) induces oxidative stress, inflammation, epithelium and endothelium damage, and cessation of renal function. The IRI is an inevitable process during kidney transplantation. Preliminary studies suggest that aminoguanidine (AG) is an antioxidant compound. In this study, we investigated the antioxidant effects of AG (50 mg/kg, intraperitoneal) and its association with molecular pathways activated by IRI (30 min/48 h) in the kidney. The antioxidant effect of AG was studied measuring GSSH/GSSG ratio, GST activity, lipoperoxidation, iNOS, and Hsp27 levels. In addition, we examined the effect of AG on elements associated with cell survival, inflammation, endothelium, and mesenchymal transition during IRI. AG prevented lipid peroxidation, increased GSH levels, and recovered the GST activity impaired by IRI. AG was associated with inhibition of iNOS, Hsp27, endothelial activation (VE-cadherin, PECAM), mesenchymal markers (vimentin, fascin, and HSP47), and inflammation (IL-1β, IL-6, Foxp3, and IL-10) upregulation. In addition, AG reduced kidney injury (NGAL, clusterin, Arg-2, and TFG-β1) and improved kidney function (glomerular filtration rate) during IRI. In conclusion, we found new evidence of the antioxidant properties of AG as a renoprotective compound during IRI. Therefore, AG is a promising compound to treat the deleterious effect of renal IRI.

Nephroprotective role of diosgenin in gentamicin-induced renal toxicity: biochemical, antioxidant, immunological and histopathological approach

Background

Aminoglycoside antibiotics, gentamicin (GM) owns the utmost nephrotoxic potential than other antibiotics from the same category. To the other side, diosgenin (DG) showed the antioxidant and anti-inflammatory property.

Results

The present study was aimed to explore the nephroprotective effect of diosgenin on gentamicin-induced renal toxicity in Wistar rats. Wistar albino rats were divided into six groups (n = 6): Normal control (NC), Nephrotoxicity control (GM), DG (20 mg/kg), DG (40 mg/kg), DG (80 mg/kg), accordingly. After the treatment, the nephroprotective effects of DG were assessed by measuring serum levels of creatinine (Cr), blood urea nitrogen (BUN), total proteins (TP), albumin and urea levels. Urine volume, proteins, electrolyte levels, creatinine clearance were also evaluated in urine samples. Oxidative stress was evaluated through the measurement of antioxidant stress markers in the kidney tissue. Changes in body weight and kidney weight were also recorded along with a histopathological examination of kidney sections. For evaluation of inflammation, TNF-α and IL-1β levels were measured in the blood serum using ELISA kits. GM intoxication induced elevated serum creatinine, BUN, urea, albumin and TP levels, urine electrolytes levels, pro-inflammatory cytokines, antioxidant parameters which were found to be decreased significantly in a dose-dependent manner in rat groups received DG which was also evidenced by the histological observations.

Conclusion

DG showed a significant nephroprotective effect in a dose-dependent manner by ameliorating the GM induced nephrotoxicity in Wistar rats.

Ameliorative role of inducible nitric oxide synthase inhibitors against sodium arsenite-induced renal and hepatic dysfunction in rats

Arsenic exposure causes immense health distress by increasing risk of cardiovascular abnormalities, diabetes mellitus, neurotoxicity, and nephrotoxicity. The present study explored the role of inducible nitric oxide synthase (iNOS) inhibitors against sodium arsenite-induced renal and hepatic dysfunction in rats. Female Sprague Dawley rats were subjected to arsenic toxicity by administering sodium arsenite (5 mg/kg/day, oral) for 4 weeks. The iNOS inhibitors, S-methylisothiourea (10 mg/kg, i.p.) and aminoguanidine (100 mg/kg, i.p.) were given one hour before sodium arsenite administration in rats for 4 weeks. Sodium arsenite led rise in serum creatinine, urea, uric acid, electrolytes (potassium, fractional excretion of sodium), microproteinuria, and decreased creatinine clearance (p < 0.001) indicated renal dysfunction in rats. Arsenic-intoxication resulted in significant oxidative stress in rat kidneys, which was measured in terms of increase in lipid peroxides, superoxide anion generation and decrease in reduced glutathione (p < 0.001) levels. A threefold increase in renal hydroxyproline level in arsenic intoxicated rats indicated fibrosis. Hematoxylin-eosin staining indicated tubular damage, whereas picrosirius red staining highlighted collagen deposition in rat kidneys. S-methylisothiourea and aminoguanidine improved renal function and attenuated arsenic led renal oxidative stress, fibrosis, and decreased the kidney injury score. Additionally, arsenite-intoxication resulted in significant rise in hepatic parameters (serum aspartate aminotransferase, alanine transferase, alkaline phosphatase, and bilirubin (p < 0.001) along with multi-fold increase in oxidative stress, fibrosis and liver injury score in rats, which was significantly (p < 0.001) attenuated by concurrent administration of iNOS inhibitors). Hence, it is concluded that iNOS inhibitors attenuate sodium arsenite-induced renal and hepatic dysfunction in rats.

Thymoquinone, but Not Metformin, Protects against Gentamicin-Induced Nephrotoxicity and Renal Dysfunction in Rats

Background: Gentamicin (GM) is an antibiotic that is widely used to treat many Gram-negative bacteria, such as those involved in urinary tract infections. However, being nephrotoxic, GM dose adjustment and reno-protective elements must be concurrently administered with GM to minimize kidney damage. Oxidative stress plays a pivotal role in the pathogenesis of GM-induced nephrotoxicity. Thymoquinone (TQ) is a promising therapeutic substance, that is being extensively studied in many diseases, such as diabetes mellitus, cancer, hypertension, and others. The powerful antioxidant properties of TQ may greatly help in minimizing GM nephrotoxicity. Metformin (MF) is a well-known, clinically approved oral hypoglycaemic drug that has many other actions, including antioxidant properties. The aim of this work was to evaluate the possible antioxidant and reno-protective effects of TQ and metformin in GM-induced nephrotoxicity in the same model (rats) at the same time. In addition, we aimed to further understand the effects underlying GM-induced nephrotoxicity. Methods: Twenty male rats were randomly divided into four equal groups: the first group (control) received distilled water; the second group received GM only; the third group received concurrent oral TQ and GM; and the fourth group received concurrent oral MF and GM. After 4 weeks, renal function and histopathology, as well as levels of the oxidative markers glutathione peroxidase-1 (GLPX1), superoxide dismutase (SOD), and malondialdehyde (MDA) in the kidney tissues, were assessed. Results: Compared with the control group, and as expected, the GM-injected rats showed significant biochemical and histological changes denoting renal damage. Compared with GM-injected rats, the concurrent administration of TQ with GM significantly reduced the levels of serum creatinine, serum urea, and tissue MDA and significantly increased the levels of GLPX1 and SOD. Concurrent metformin administration with GM significantly increased the levels of both GLPX1 and SOD and significantly decreased the levels of tissue MDA but had no significant effect on serum creatinine and urea levels. Compared with GM-injected rats, the addition of either TQ or MF resulted in a reduction in endothelial proliferation and mesangial hypercellularity. Conclusions: Both TQ and MF effectively alleviated the oxidative stress in GM-induced nephrotoxicity in rats, with TQ but not MF producing a complete reno-protective effect. Further studies for evaluation of different reno-protective mechanisms of TQ should be conducted.

D-Limonene Alleviates Acute Kidney Injury Following Gentamicin Administration in Rats: Role of NF-κB Pathway, Mitochondrial Apoptosis, Oxidative Stress, and PCNA

Clinical application of gentamicin (GM) is well known to be associated with the development of acute kidney injury (AKI). This study was the first to investigate the possible protective effects of D-limonene (D-lim) on AKI following GM administration in rats. 32 rats arranged in four groups (n = 8): (1) the control group received saline intraperitoneally (0.5 ml/day) and orally (0.5 ml/day), (2) the D-lim group received D-lim (100 mg/kg) orally and saline (0.5 ml/day) intraperitoneally, (3) the GM group received GM (100 mg/kg/day) intraperitoneally and saline (0.5 ml/day) orally, and (4) the treated group received intraperitoneal GM (100 mg/kg) and oral D-lim (100 mg/kg). All treatments were performed daily for 12 consecutive days. Results revealed that D-lim ameliorated GM-induced AKI, oxidative stress, mitochondrial apoptosis, and inflammation. D-lim showed nephroprotective effects as reflected by the decrease in serum urea and creatinine and improvement of renal histopathological changes. D-lim alleviated GM-induced oxidative stress by increasing the activities of renal catalase, serum and renal glutathione peroxidase, and renal superoxide dismutase and decreasing renal malondialdehyde and serum nitric oxide levels. Intriguingly, D-lim suppressed mitochondrial apoptosis by considerably downregulating Bax and caspase-3 (Casp-3) mRNA and protein expressions and markedly enhancing Bcl2 mRNA and protein expressions. Furthermore, D-lim significantly decreases GM-induced inflammatory response through downregulation of NF-κB, IL-6, and TNF-α mRNA and/or protein expressions and decrease in renal myeloperoxidase activity. Finally, D-lim remarkably downregulated PCNA protein expression in the treated group compared with the GM group. In brief, this study showed that D-lim alleviated AKI following GM administration in rats, partially through its antioxidant, anti-inflammatory, and antiapoptotic activities as well as downregulation of PCNA expression.

Morphometric analysis of structural renal alterations and beneficial effects of aminoguanidine in acute kidney injury induced by cisplatin in rats

Since cisplatin-induced nephrotoxicity has very important clinical consequences, the purpose of this study was to determine the potential protective effect of aminoguanidine on the acute kidney injury caused by cisplatin. Experiments were done on 40 Wistar rats divided into four groups. The CIS group received cisplatin in a single dose of 8 mg/kg, while the CISAG group received the same dose of cisplatin and aminoguanidine (100 mg/kg) by intraperitoneal injections. Animals in the AG group received only aminoguanidine (100 mg/kg) and those in the C group received saline. Quantitative evaluation of structural and functional alterations in the kidneys was performed by analysis of biochemical and parameters of oxidative stress and by histological and morphometric analysis of renal sections. Histological sections of kidney showed structural damage of proximal tubules and glomeruli that were induced by cisplatin. Morphometric analysis revealed statistically significant differences in the area of proximal tubules and the size and cellularity of glomeruli between the CIS and CISAG groups. Glomerular basement membrane thickness was increased in the CIS group, while aminoguanidine attenuated these changes in the CISAG group of rats. Our results suggest that aminoguanidine acts protectively and repairs structural and functional damage of kidney by engaging the existent antioxidative potential at the level of renal tissue.

Pioglitazone attenuates kidney injury in an experimental model of gentamicin-induced nephrotoxicity in rats

Gentamicin, belonging to the aminoglycosides, possesses the greatest nephrotoxic effect of all other antibiotics from this group. On the other hand, pioglitazone, which represents peroxisome proliferator-activated receptor γ (PPARγ) agonist recently showed antiinflamatory, antioxidative effects, amelioration of endothelial dysfunction etc. Therefore, the goal of our study was to investigate the effects of pioglitazone on kidney injury in an experimental model of gentamicin-induced nephrotoxicity in rats. These effects were observed by following values of biochemical (serum urea and creatinine) parametars, total histological kidney score, urine level of kidney injury molecule-1 (KIM-1) and neutrophil gelatinase-associated lipocalin (NGAL) as well as parametars of oxidative stress (malondialdehyde, superoxide dismutase, catalase, total oxidant status, total antioxidant status, oxidative stress index and advanced oxidation protein products). It seems that pioglitazone protects the injured rat kidney in a U-shaped manner. Medium dose of pioglitazone (1 mg/kg, i.p.) was protective regarding biochemical (serum urea and creatinine), total histological score and the values of kidney injury molecule-1 (KIM-1) (P < 0.05 vs. control group, i.e. rats injected with gentamicin only). This finding could be of great importance for the wider use of aminoglycosides, with therapy that would reduce the occurrence of serious adverse effects, such as nephrotoxicity and acute renal failure.

Excessive Oxidative Stress Contributes to Increased Acute ER Stress Kidney Injury in Aged Mice

The aged kidney is susceptible to acute injury due presumably to its decreased ability to handle additional challenges, such as endoplasmic reticulum (ER) stress. This was tested by giving tunicamycin, an ER stress inducer, to either old or young mice. Injection of high dose caused renal failure in old mice, not in young mice. Moreover, injection of low dose resulted in severe renal damage in old mice, confirming the increased susceptibility of aged kidney to ER stress. There existed an abnormality in ER stress response kinetics in aged kidney, characterized by a loss of XBP-1 splicing and decreased PERK-eIF2α phosphorylation at late time point. The presence of excessive oxidative stress in aged kidney may play a role since high levels of oxidation increased ER stress-induced cell death and decreased IRE1 levels and XBP-1 splicing. Importantly, treatment with antioxidants protected old mice from kidney injury and normalized IRE1 and XBP-1 responses. Furthermore, older mice (6 months old) transgenic with antioxidative stress AGER1 were protected from ER stress-induced kidney injury. In conclusion, the decreased ability to handle ER stress, partly due to the presence of excessive oxidative stress, may contribute to increased susceptibility of the aging kidney to acute injury.

Protective Effects of Curcumin Against Nephrotoxic Agents

BACKGROUND

Curcumin is the one of the main phenolic ingredients in curcuma species rhizome. Curcuma species have traditionally been used for the treatment of diabetes, cardiovascular, and renal diseases.

METHODS

The present study was designed to review the scientific literature on the protective effects of curcumin against nephrotoxic agents.

RESULTS

Studies have shown the protective effects of curcumin against nephrotoxic agents such as gallic acid, glucose, tartrazine, streptozotocin, lead, cadmium, fluoride, maleate, malathion, nicotine, cisplatin, gentamicin, and methotrexate. However, further investigations are needed to determine the efficacy of curcumin as an antidote agent due to the lack of clinical trial studies. Therefore, it is recommended to conduct clinical trials in humans to confirm these effects.

CONCLUSION

The current review indicated that curcumin may be effective against nephrotoxicity by modulating oxidative stress and inflammatory responses.

Vitamin D attenuates gentamicin-induced acute renal damage via prevention of oxidative stress and DNA damage

Background:

Despite being one of the most nephrotoxic drugs, gentamicin (GM) remains a mainstay as a first-choice agent in a vast variety of clinical situations owing to its superlative efficiency as a broad-spectrum antibiotic in treating several life-threatening bacterial infections. This urgently calls for the need for in-depth analysis of the mechanisms governing GM-induced nephrotoxicity and entails the necessity of presenting novel protective agents capable of ameliorating those renal deleterious effects. The reactive oxygen species and redox-sensitive transcription factors in GM-induced nephrotoxicity have recently called attention.

Purpose:

This study has been designed to shed light on the possible mechanisms of GM-induced nephrotoxicity and to provide a consensus set of histopathological, immunohistochemical, genetic and biochemical parameters elucidating the protective role of vitamin D against this nephrotoxicity.

Methods:

Twenty-four adult male albino rats were equally divided into four groups: group I (control group), group II (GM), group III (GM + vitamin D) and group IV (vitamin D only). Kidney function tests, histopathological examination, gene expression of nuclear factor 2, nuclear factor kappa beta (NF-κB) and western blot of NF-κB p65, assessment of glutathione peroxidase and nicotinamide adenine dinucleotide phosphate oxidase (NADPH) oxidase by ELISA, as well as immunohistochemical evaluation of inducible nitric oxide, malondialdehyde, 8-hydroxy 2 deoxyguanine and vitamin D receptor, have been carried out.

Results:

The kidney function deterioration, tissue oxidative stress development and the histopathological changes induced by GM were significantly attenuated by vitamin D administration.

Conclusion:

Vitamin D attenuates GM nephrotoxicity through its antioxidant properties and prevention of DNA damage.

Reno-protective effects of ursodeoxycholic acid against gentamicin-induced nephrotoxicity through modulation of NF-κB, eNOS and caspase-3 expressions

Gentamicin (GNT) is a potent aminoglycoside antibiotic widely used to treat life-threatening bacterial infections. We aim to investigate the potential protective effect of ursodeoxycholic acid (UDCA) against GNT-induced nephrotoxicity. In this study, 24 male Wistar rats were used and randomly divided into four groups of six animals each. Control group received 0.5% carboxymethyl cellulose orally for 15 days, GNT group received GNT 100 mg/kg/day i.p. for 8 days, UDCA group received UDCA orally for 15 consecutive days at a dose of 60 mg/kg/day suspended in 0.5% carboxymethyl cellulose and UDCA-pretreated group received UDCA orally for 7 days then co-administered with GNT i.p. for 8 days at the same fore-mentioned doses. Serum levels of kidney function parameters (urea, creatinine, uric acid and albumin) were measured. Renal tissues were used to evaluate oxidative stress markers; malonaldehyde (MDA), reduced glutathione (GSH) and the anti-oxidant enzyme superoxide dismutase (SOD) activities and nuclear factor kappa light-chain enhancer of activated B cells (NF-κB) and kidney injury molecule-1 (KIM-1) mRNA levels. Immunohistochemical expression of endothelial nitric oxide synthase (eNOS) and caspase-3 and histological and ultrastructural examination were performed. Treatment with GNT increased the serum levels of renal function parameters and renal MDA, NF-κB and KIM-1 mRNA levels, while it decreased GSH and SOD activities. Marked immunohistochemical expression of caspase-3 was observed after GNT administration while it decreased eNOS expression. Histological and ultrastructural alterations were also evident in renal corpuscles and tubules. In contrast, pretreatment with UDCA reversed changes caused by GNT administration. These results suggest that UDCA ameliorates GNT-induced kidney injury via inhibition of oxidative stress, inflammation and apoptosis.

Kiwi fruit (Actinidia deliciosa) ameliorates gentamicin-induced nephrotoxicity in albino mice via the activation of Nrf2 and the inhibition of NF-κB (Kiwi & gentamicin-induced nephrotoxicity)

Gentamicin is a potent aminoglycoside antibiotic, but the risk of nephrotoxicity limits its prolonged use. The toxicity of gentamicin is believed to result from oxidative stress, a condition that could be counteracted by dietary antioxidants. This study determines the possible renoprotective effects of kiwifruit against the pathophysiological and ultrastructural alterations induced by gentamicin. Mice were intraperitoneally injected with gentamicin (100mg/kg body weight) for eight consecutive days, and kiwi juice was administered for 8days, either concomitant to or after gentamicin injection. Gentamicin caused nephrotoxicity evidenced by the significant elevation of serum creatinine and blood urea nitrogen levels, along with significant reduction of serum sodium and potassium ions, compared to normal controls. This was associated with proximal tubular necrosis, lysosomal accumulation and mitochondrial alterations, together with glomerular atrophy, mesangial hypercellularity, and inflammatory cell infiltration. Moreover, immunohistochemical results pointed to the relevant role of Nrf2 and NF-κB in gentamicin-induced nephrotoxicity. Kiwi administration, especially when given after gentamicin injection, significantly ameliorated gentamicin-induced pathophysiological alterations, increased the nuclear immunoreactivity of Nrf2 and decreased that of NF-κB. In short, kiwi fruit shows a promising role as a nephroprotective agent against gentamicin-induced nephrotoxicity via attenuating oxidative stress, inflammation and cell death.

Protective impact of resveratrol in experimental rat model of hyperoxaluria

PURPOSE

Resveratrol (RES) is a polyphenol with antioxidant, anti-inflammatory, and many other physiological effects on tissues. In the present study, the effect of resveratrol in hyperoxaluria driven nephrolithiasis/nephrocalcinosis is investigated.

METHODS

Wistar-Albino rats of 250-300 g (male, n = 24) were included in the present study. The rats were randomized into three groups: Group 1 consisted of the controls (n = 8), Group 2 of hyperoxaluria (1% ethylene glycol (EG), n = 8), and Group 3 of the treatment (1% EG + 10 mg/kg of RES, n = 8) group. At the beginning and fifth week of the study, two rats from each group were placed in metabolic cages for 24 h and their urine was collected. At the end of the study, the rats were killed and their blood was collected from the vena cava inferior. The right kidneys of the rats were used for biochemical and the left ones for immunohistochemical analyzes. Malondialdehyde (MDA), catalase, urea, calcium, oxalate, and creatinine clearance were studied in the blood, urine, and kidney tissues. Moreover, routine histological evaluation, and p38-MAPK and NFkB immunohistochemical analyses were conducted.

RESULTS

In the hyperoxaluria group, urinary oxalate levels were higher than the control group; yet, lower in the treatment group compared to hyperoxaluria group (p < 0.05). Serum MDA levels in the hyperoxaluria group were higher than the control group; but in the treatment group it is lower than the hyperoxaluria group (p < 0.05). P38 MAPK activity was higher in the hyperoxaluria group compared to the control (p < 0.05). However, in terms of p38 MAPK activity, there were no statistically significant difference between hyperoxaluria and the treatment group (p < 0.069). Whereas NFkB activity in the hyperoxaluria group is higher than the control (p < 0.001), no statistically significant difference was observed with the treatment group.

CONCLUSIONS

In the present study, resveratrol was seen to prevent hyperoxaluria. With preventing oxidative stress factors and Randall plaque formation caused by free oxygen radicals, resveratrol can be an alternative treatment option that can increase the success rate in preventing stone recurrence in the future.

Aminoguanidine treatment increased NOX2 response in diabetic rats: Improved phagocytosis and killing of Candida albicans by neutrophils

In this study, we show that aminoguanidine (AMG), an inhibitor of protein glycation, increases the NOX2 (phagocyte NADPH oxidase) response and microbicidal activity by neutrophils, regardless of diabetic status. The non-enzymatic glycation of proteins, yielding irreversible advanced glycation end products (AGEs), is involved in the development of diabetes complications, including alterations of signaling pathways and the generation of reactive oxygen species by phagocytes. The phagocytes produce ROS (reactive oxygen species) through activation of the NOX2 complex, which generates superoxide. The purpose of this study was to evaluate the effect of hyperglycemia and the glycation of proteins on the NOX2 activity of neutrophils and its implications for cellular physiology, with a focus on the microbicidal activity of these cells. We treated diabetic rats with AMG and evaluated neutrophil ROS generation and Candida albicans killing ability. We observed a large increase in the microbicidal activity of peritoneal neutrophils from AMG-treated rats. The increase was independent of diabetic status and myeloperoxidase activity. Collectively, our results suggest that AMG has an immunomodulator role that triggers an increase in the microbicidal response of neutrophils mainly related to reactive oxygen species production by NOX2.

Antitumor efficacy of tangeretin by targeting the oxidative stress mediated on 7,12-dimethylbenz(a) anthracene-induced proliferative breast cancer in Sprague-Dawley rats

PURPOSE

The aim of the present study was to assess the chemopreventive and chemotherapeutic efficacy of tangeretin on DMBA-induced oxidative stress in breast cancer-bearing Sprague-Dawley rats.

METHODS

In this study, the experimental animals were divided into five groups of six animals each. Group I was control, Group II was DMBA-induced breast cancer-bearing rats, Group III was tangeretin pre-treated (50 mg/kg body weight for 30 days orally) breast cancer-bearing animals, Group IV was tangeretin post-treated (50 mg/kg body weight for 30 days orally) and Group V was tangeretin (50 mg/kg body weight) alone treated animals.

RESULTS

We have observed the general characteristics of cancer, oxidative stress markers, breast cancer marker, antioxidants and histopathological changes in the experimental animals. We have recorded the body weight, tumor weights, tumor volume and antitumor activity of tangeretin in the experimental animals. Oxidative stress markers, like NO and LPO, and breast cancer marker CEA levels were significantly (p < 0.001, p < 0.05) increased as well as the antioxidants like SOD, CAT, GPx, GST, GSH, ascorbic acid and α-tocopherol were found to be significantly (p < 0.05) decreased in cancer-bearing Group II animals. Whereas, the enzymic and non-enzymic antioxidant levels were found to be significantly decreased in cancer-bearing animals. However, in tangeretin pre-treated and post- treated animals, the levels of antioxidants and breast cancer marker were found to be significantly (p < 0.05) reduced with a concomitant increase in the activities of the antioxidants (p < 0.05). In tangeretin alone treated Group V animals, no significant changes were observed in the levels of antioxidants and breast cancer marker. These results were adequately supported by the histopathological studies in the mammary tissues of the experimental animals.

CONCLUSION

From this study, we conclude that the administration of tangeretin was found to be beneficial against DMBA-induced oxidative stress in breast cancer-bearing animals. Hence, we strongly suggest that tangeretin is effective and efficient candidate for the treatment of experimental breast cancer.

Effects of aminoguanidine and melatonin on intestinal ischemia/reperfusion injury in rats: An assessor-blinded, controlled experimental study

BACKGROUND

The reactive oxygen and nitrogen species generated during reperfusion of tissue are characteristic of intestinal ischemia and reperfusion (IIR) injury.

OBJECTIVE

This study was designed to assess whether the administration of aminoguanidine (AG), a selective nitric oxide synthase inhibitor, and/or melatonin has protective potential in IIR injury.

METHODS

Male Wistar albino rats (age, 3-4 weeks; weight, 100-150 g) were divided in a nonrandom fashion into 5 groups of equal size: group 1, IIR injury + AG 100 mg/kg; group 2, IIR injury + melatonin 10 mg/kg; group 3, IIR injury + AG 100 mg/kg + melatonin 10 mg/kg; group 4, sham operation; and group 5, IIR injury alone. Sixty minutes of intestinal ischemia and 4 hours of reperfusion were carried out in all but the sham-operation group. Ileal specimens were obtained from all rats to determine the extent of histologic changes, measure tissue concentrations of malondialdehyde (MDA) and protein carbonyl (PC), and assess the activity of superoxide dismutase (SOD) and glutathione peroxidase (GPx). Specimens were also assessed and scored by a pathologist blinded to the experiment and the data.

RESULTS

Forty rats were divided into 5 groups of 8 each; all 40 survived until study end. In the IIR injury-alone group, mean (SD) MDA concentration and PC content were significantly higher than that of the sham-operation group, and SOD and GPx activity were significantly lower: MDA concentration, 0.86 (0.03) versus 0.54 (0.01) mmol/g protein, respectively; PC content, 0.60 (0.02) versus 0.34 (0.01) mmol/g protein; SOD activity, 104.33 (43.14) versus 2954.72 (109.55) U/g protein; and GPx activity, 10.44 (0.63) versus 24.34 (1.77) U/g protein (all, P < 0.001). Administration of AG, melatonin, and the AG/melatonin combination was associated with significantly higher SOD (1802.31 [102.35], 1776.50 [58.41], and 1924.28 [98.10] U/g protein, respectively) and GPx (17.36 [1.23], 15.96 [1.08], and 18.06 [1.72] U/g protein) activity and significantly lower MDA concentration (0.62 [0.02], 0.64 [0.02], and 0.56 [0.01] mmol/g protein) and PC content (0.53 [0.03], 0.51 [0.01], and 0.49 [0.02] mmol/g protein) compared with the IIR injury-alone group (P < 0.001). Mean intestinal mucosal injury scores were significantly lower in the 3 treatment groups (2.12 [0.35], 1.75 [0.46], and 1.12 [0.35]) compared with the IIR injury-alone group (3.87 [0.35]; all, P < 0.001).

CONCLUSION

In this study, AG, melatonin, or both administered in combination were associated with improvements in oxidative markers in this rat model of IIR injury.

Gingerol fraction from Zingiber officinale protects against gentamicin-induced nephrotoxicity

Nephrotoxicity is the main complication of gentamicin (GM) treatment. GM induces renal damage by overproduction of reactive oxygen species and inflammation in proximal tubular cells. Phenolic compounds from ginger, called gingerols, have been demonstrated to have antioxidant and anti-inflammatory effects. We investigated if oral treatment with an enriched solution of gingerols (GF) would promote a nephroprotective effect in an animal nephropathy model. The following six groups of male Wistar rats were studied: (i) control group (CT group); (ii) gingerol solution control group (GF group); (iii) gentamicin treatment group (GM group), receiving 100 mg/kg of body weight intraperitoneally (i.p.); and (iv to vi) gentamicin groups also receiving GF, at doses of 6.25, 12.5, and 25 mg/kg, respectively (GM+GF groups). Animals from the GM group had a significant decrease in creatinine clearance and higher levels of urinary protein excretion. This was associated with markers of oxidative stress and nitric oxide production. Also, there were increases of the mRNA levels for proinflammatory cytokines (tumor necrosis factor alpha [TNF-α], interleukin-1β [IL-1β], IL-2, and gamma interferon [IFN-γ]). Histopathological findings of tubular degeneration and inflammatory cell infiltration reinforced GM-induced nephrotoxicity. All these alterations were attenuated by previous oral treatment with GF. Animals from the GM+GF groups showed amelioration in renal function parameters and reduced lipid peroxidation and nitrosative stress, in addition to an increment in the levels of glutathione (GSH) and superoxide dismutase (SOD) activity. Gingerols also promoted significant reductions in mRNA transcription for TNF-α, IL-2, and IFN-γ. These effects were dose dependent. These results demonstrate that GF promotes a nephroprotective effect on GM-mediated nephropathy by oxidative stress, inflammatory processes, and renal dysfunction.

In vivo study of radioprotective effect of NO-synthase inhibitors and acetyl-L-carnitine

This study investigated the protective effect of two nitric oxide synthase inhibitors N(omega)-nitro-L-arginine methyl ester (L-NAME, 100 mg/kg i.p.) and aminoguanidine (AG, 400 mg/kg i.p.), and an antioxidant acetyl-L-carnitine (ALC, 250 mg/kg i.p., once daily for five days) against radiation-induced damage in Wistar rats. Blood samples were collected 6 h after whole-body irradiation with 8 Gy. Plasma concentrations of nitrite+nitrate (NO(x)) and malondialdehyde (MDA) were measured by high-performance liquid chromatography. A single injection of L-NAME one hour before exposure effectively prevented the radiation-induced elevation of plasma NO(x) and it reduced 2.6-fold the risk for death during the subsequent 30-day period. Pretreatment with ALC prevented the radiation-induced increase in plasma MDA and it had similar effect on mortality as L-NAME did. Presumably due to its short half-life, the partially iNOS-selective inhibitor and antioxidant AG given in a single dose before exposure did not attenuate MDA and NO(x) and it failed to significantly improve the 30-day survival. In conclusion, pretreatment with both the nonspecific NOS inhibitor L-NAME and the antioxidant ALC markedly reduce mortality to radiation sickness in rats. The radioprotective effect may be directly related to effective attenuation of the radiation-induced elevation of NO production by L-NAME and of oxidative stress by ALC.

Ascorbic acid reduces gentamicin-induced nephrotoxicity in rats through the control of reactive oxygen species

BACKGROUND & AIM

Oxidative stress has been implicated in the pathophysiology of many forms of acute renal failure. The aim was examine the effect of vitamin C on oxidative stress and its relationship with nitric oxide on gentamicin-induced nephrotoxicity in rats.

METHODS

We utilized 32 Wistar rats allocated in four groups of eight animals each: control (CTL), vitamin C (VIT C), gentamicin (GENTA), and GENTA + VIT C; all groups were treated during seven days.

RESULTS

Serum urea and creatinine, serum and renal tissue malondialdehyde, blood superoxide anion and hydrogen peroxide in GENTA were increased vs CTL and vs VIT C, and decreased in GENTA + VIT C vs GENTA (all P < 0.05). Serum nitric oxide increased in GENTA vs CTL and vs VIT C, and reduced in GENTA + VIT C vs GENTA (P < 0.001). Urinary nitric oxide was reduced in GENTA vs CTL and vs VIT C and increased in GENTA + VIT C vs GENTA (P < 0.001). Severe degeneration of proximal tubules was present in GENTA, but only mild lesions were observed in GENTA + VIT C.

CONCLUSION

This study suggests that VIT C is a valuable tool to protect against GENTA-induced nephrotoxicity, by reducing reactive oxygen species and increasing the nitric oxide.

Histone deacetylase inhibitor, sodium butyrate, attenuates gentamicin-induced nephrotoxicity by increasing prohibitin protein expression in rats

The major purpose in our study was to investigate the effects of sodium butyrate (NaBu) on nephrotoxicity induced by gentamicin in rats and determine further whether the protective effect is mediated by modulation of prohibitin protein expression. Gentamicin was injected intraperitoneally (100 mg/kg body weight) once daily for 8 days to induce nephrotoxicity. The effect of acute and chronic treatment of sodium butyrate on nephrotoxicity induced by gentamicin was assessed. Various doses of sodium butyrate (50, 100, 200 mg/kg, i.p.) was administered 30 min prior to the daily gentamicin injection. Histological analysis was used to evaluate the lesions in kidney after gentamicin administration. Expression of prohibitin was evaluated with immunohistochemical and western blot analysis. The present study demonstrated that gentamicin treatment for 8 consecutive days significantly increased in the levels of blood urea nitrogen, creatinine, kidney injury molecule (KIM-1) and neutrophil gelatinase-associated lipocalin (NGAL) which indicated nephrotoxicity induced by gentamicin. In addition, chronic treatment with NaBu significantly attenuated gentamicin-induced nephrotoxicity by increasing activities of superoxide dismutase, catalase and reduced glutathione. Immunohistochemical studies in gentamicin-induced rats also demonstrated an increase in the levels of inducible prohibitin after treatment with sodium butyrate. Our results indicated that sodium butyrate, a histone deacetylase inhibitor, decreased gentamicin-induced nephrotoxicity by enhancing renal antioxidant enzymes activity and the expression of prohibitin protein.

The effects of vitamin d on gentamicin-induced acute kidney injury in experimental rat model

Introduction. Acute kidney injury (AKI) pathogenesis is complex. Findings of gentamicin nephrotoxicity are seen in 30% of the AKI patients. Vitamin D has proven to be effective on renin expression, inflammatory response, oxidative stress, apoptosis, and atherosclerosis. We aimed to investigate the effect of vitamin D in an experimental rat model of gentamicin-induced AKI. Methods. Thirty nonuremic Wistar albino rats were divided into 3 groups: Control group, 1 mL saline intramuscular (im) daily; Genta group, gentamicin 100 mg/kg/day (im); Genta + vitamin D, gentamicin 100 mg/kg/day (im) in addition to 1 α , 25 (OH)2D3 0.4 mcg/kg/day subcutaneously for 8 days. Blood pressures and 24-hour urine were measured. Blood urea and creatinine levels and urine tubular injury markers were measured. Renal histology was semiquantitatively assessed. Results. Urea, creatinine and urine neutrophil gelatinase-associated lipocalin, and kidney injury molecule-1 were all increased in Genta group indicating AKI model. Systolic blood pressure decreased, but urine volume and glutathione increased in Genta + Vit D group compared to Control group. Histological scores indicating tubular injury increased in Genta and Genta + Vit D groups. Conclusions. Vitamin D does not seem to be effective on histological findings although it has some beneficial effects via RAS system and a promising effect on antioxidant system.

Prevention of hepatic and renal toxicity with bradykinin potentiating factor (BPF) isolated from Egyptian scorpion venom (Buthus occitanus) in gentamicin treated rats

The present investigation report the effect of a bradykinin-potentiating factor (BPF) on gentamicin-induced oxidative stress in rat liver and kidney. BPF is a peptide fraction isolated from the venom of the Egyptian scorpion (Buthus occitanus) has been demonstrated to have antioxidant, free radical scavenger and anti-inflammatory effects. Thirty male Rattus norvegicus (130-150 g) were included and divided into three equal groups as follows: Group I (control), group II was (ip) injected with gentamicin alone (80 mg/kg/day) for 15 days, group III was given (ip) injection of BPF (1mg/kg/day) one hour prior to gentamicin treatment for 15 days with the same dose of gentamicin as group II. Both organs were subjected to histopathological analysis with the light microscope. The activities of alanine aminotransferase (ALT), asparate aminotransferase (AST) and alkaline phosphatase (ALP) in serum were measured as indicators of the liver function. As parameters of the kidney function, creatinine, uric acid and urea concentrations were determined. Also, malondialdehyde (MDA), reduced glutathione (GSH), super oxide dismutase (SOD) and catalase (CAT) were determined in both tissues. Gentamicin caused a significant decrease or inhibition in the activities of GSH, SOD, and CAT, with significant increase in the level of MDA, ALT, AST, ALP, as well as creatinine, uric acid and urea concentrations in versus to control groups in both liver and kidney. Co-administration of gentamicin and BPF significantly increased the activity of GSH, SOD, and CAT, with significant decrease in the level of MDA and maintained serum (ALT); (AST); (ALP), creatinine, uric acid and urea concentrations as the same level as control group. Moreover, administration of gentamicin resulted in damage to liver and kidney structures. Administration of BPF before gentamicin exposure prevented severe alterations of biochemical parameters and disruptions of liver and kidney structures. In conclusion, this study obviously demonstrated that pretreatment with BPF significantly attenuated the physiological and histopathological alterations induced by gentamicin. Also, the present study identifies new areas of research for development of better therapeutic agents for liver, kidney, and other organs dysfunctions and diseases.

Nephroprotective activity of Solanum xanthocarpum fruit extract against gentamicin-induced nephrotoxicity and renal dysfunction in experimental rodents

OBJECTIVE

To evaluate nephroprotective potential of Solanum xanthocarpum (S. xanthocarpum) fruit extract(SXE) against gentamicin (GM) induced nephrotoxicity and renal dysfunction.

METHODS

Twenty-four Wistar rats were divided into four groups (n=6). Control rats that received normal saline (i.p.) and 0.5% carboxymethyl cellulose (p.o.) per day for 8 d. Nephrotoxicity was induced in rats by intraperitoneal administration of GM (100 mg/kg/d for 8 d) and were treated with SXE (200 and 400 mg/kg/d (p.o.) for 8 d). Plasma and urine urea and creatinine, kidney weight, urine output, blood urea nitrogen, renal enzymatic and non-enzymatic antioxidants and lipid peroxidation was evaluated along with histopathological investigation in various experimental groups of rats.

RESULTS

It was observed that the GM treatment induced significant elevation (P<0.001) in plasma and urine urea, creatinine, kidney weight, blood urea nitrogen, renal lipid peroxidation along with significant decrement (P<0.001) in urine output, renal enzymatic and non-enzymatic antioxidants. SXE 200 and 400 mg/kg treatment to GM treated rats recorded significant decrement (up to P<0.001) in plasma and urine urea and creatinine, renal lipid peroxidation along with significant increment (up to P<0.001) in renal enzymatic and non-enzymatic antioxidants. Histological observations of kidney tissues too correlated with the biochemical observations.

CONCLUSIONS

These finding powerfully supports that S. xanthocarpum fruit extract acts in the kidney as a potent scavenger of free radicals to prevent the toxic effects of GM both in the biochemical and histopathological parameters and thus validates its ethnomedicinal use.

Renal protective effect of hesperidin on gentamicin-induced acute nephrotoxicity in male Wistar albino rats

OBJECTIVES

The aim of the study was to investigate the renoprotective effect of hesperidin (HDN), a citrus flavanoid with anti-oxidant properties against gentamicin (GEN)-induced nephrotoxicity in male Wistar albino rats.

METHODS

Urea, uric acid, creatinine, thiobarbituric acid reactive substances (TBARS), nitric oxide (NO), total cholesterol, free fatty acids, and triglyceride levels were measured in the serum. Further, glutathione (GSH), superoxide dismutase (SOD), and glutathione peroxidase (GPx) activities were determined in the erythrocytes. Morphological changes in renal tissues were examined using light microscopy.

RESULTS

Acute renal injury was evidenced by: (1) increased serum urea, uric acid, creatinine, TBARS, and NO, (2) decreased SOD, GPx, and GSH levels, and (3) necrosis in proximal tubules and glomerular atrophy. HDN supplementation to GEN-induced rats significantly decreased serum urea, uric acid, creatinine, TBARS, NO generation, but SOD, GPx activities, and GSH content increased when compared with GEN alone. Moreover, HDN supplementation resulted in complete reversal of GEN-induced tubular necrosis, and an increase in total cholesterol, free fatty acids, and triglycerides to normal levels.

DISCUSSION

Our results suggested that HDN acts as a potent scavenger of free radicals in the kidney to prevent the toxic effects of GEN both at the biochemical and histopathological levels.

Nephroprotective activity of Macrothelypteris oligophlebia rhizomes ethanol extract

CONTEXT

Macrothelypteris oligophlebia (Bak.) Ching (Thelypteridaceae) is a Chinese herbal medicine used traditionally for the treatment of diseases such as edema, boils, burns, and roundworms. However, research about the nephroprotective potential of this plant is not available.

OBJECTIVE

Present study was designed to evaluate the protective effect of ethanol extract of M. oligophlebia rhizomes (EMO) on gentamicin (GM)-induced nephrotoxicity.

MATERIALS AND METHODS

Rats were intraperitoneal (i.p.) injected with GM (100 mg/kg) to induce nephrotoxicity and simultaneously EMO (250 and 500 mg/kg) was orally given to GM-treated rats for 8 days. Blood urea nitrogen (BUN), serum creatinine (Cr), malondialdehyde (MDA), nitric oxide (NO), superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) were evaluated in renal tissues. Histopathological analysis was used for evaluation of the renal damage.

RESULTS

Administration with GM-induced renal dysfunction in rats. Pre-treatment with EMO (500 mg/kg) significantly decreased the levels of BUN, Cr, MDA and NO (decreased BUN from 12.71 ± 1.28 to 7.19 ± 0.23 mmol/l, Cr from 39.77 ± 5.34 to 19.17 ± 0.90 μmol/l, MDA from 5.60 ± 0.37 to 2.63 ± 0.24 nmol/ml, and NO from 868.17 ± 22.67 to 589.51 ± 8.83 μmol/ml), and also restored the activities of renal antioxidant enzymes (SOD, CAT, and GSH-Px) (restored SOD from 1.59 ± 0.17 to 2.94 ± 0.13 U/mg protein, CAT from 3.22 ± 0.34 to 10.57 ± 0.27 U/mg protein, and GSH-Px from 9.11 ± 1.29 to 20.72 ± 1.83 U/mg protein).

DISCUSSION AND CONCLUSION

Our results suggest that the rhizomes of M. oligophlebia potentially have a protective role in renal tissue against oxidative stress in acute renal failure.

Effect of rosmarinic acid on inhibition of gentamicin induced nephrotoxicity in rats

The present investigation reports the effect of rosmarinic acid (RA), an antioxidant on gentamicin sulphate (GS)-induced renal oxidative damage in rats. Rosmarinic acid (RA) has been demonstrated to have antioxidant, free radical scavenger and anti-inflammatory effects. Twenty-eight Sprague-Dawley rats were divided in to four equal groups as follows: group 1 (control), group 2 (GS 100 mg/kg/d ip), group 3 (GS 100 mg/kg/d ip+RA 50 mg/kg/d) and group 4 (GS 100 mg/kg/d ip+RA 100 mg/kg/d). Treatments were administrated once daily for 12 days. After 12 days 24h urine was collected, blood was sampled and kidneys were removed. Serum and kidney tissue MDA assessed by thiobarbituric acid. Kidney paraffin sections (5 μm thickness) from the left kidney stained with periodic acid Schiff. Tubular necrosis was studied semiquantitatively and glomerular volume and volume density of proximal convoluted tubule (PCT) estimated stereologically. Kidney homogenize were prepared from right kidney. Serum creatinine, urea and kidney antioxidant enzymes activity were assessed by special kits. Data were compared by SPSS 13 software and Mann-Whitney test at p < 0.05. Co treatment of GS and RA (High dose) significantly decreased serum creatinine, MDA, urea, tubular necrosis (p < 0.05) and increase renal GSH, GPX, CAT, SOD, volume density of PCT and creatinine clearance significantly in comparison with GS group (p < 0.05). Treatment with RA (high dose) maintained serum creatinine, volume density of PCT, renal GSH, GPX, SOD and MDA as the same level as control group significantly (p < 0.05). In conclusion, RA alleviates GS nephrotoxicity via antioxidant activity, increase of renal GSH content and increase of renal antioxidant enzymes activity.

Hesperidin alleviates acetaminophen induced toxicity in Wistar rats by abrogation of oxidative stress, apoptosis and inflammation

Acetaminophen (APAP) is a widely used analgesic and antipyretic drug, but at high dose it leads to undesirable side effects, such as hepatotoxicity and nephrotoxicity. The present study demonstrates the comparative hepatoprotective and nephroprotective activity of hesperidin (HD), a naturally occurring bioflavonoid against APAP induced toxicity. APAP induces hepatotoxicity and nephrotoxicity as was evident by abnormal deviation in the levels of antioxidant enzymes. Moreover, APAP induced renal damage by inducing apoptotic death and inflammation in renal tubular cells, manifested by an increase in the expression of caspase-3, caspase-9, NFkB, iNOS, Kim-1 and decrease in Bcl-2 expression. These results were further supported by the histopathological examination of kidney. All these features of APAP toxicity were reversed by the co-administration of HD. Therefore, our study favors the view that HD may be a useful modulator in alleviating APAP induced oxidative stress and toxicity.

Protective effect of aminoguanidine against cyclophosphamide-induced oxidative stress and renal damage in rats

BACKGROUND

Cyclophosphamide (CP) is widely used in the treatment of tumors and B-cell malignant disease, such as lymphoma, myeloma, chronic lymphocytic leukemia, and Waldenstrom's macroglobulinemia. Renal damage is one of the dose-limiting side effects of CP. Oxidative stress is reported to play important roles in CP-induced renal damage.

AIM

To find out whether aminoguanidine (AG) protects against CP-induced oxidative stress and renal damage.

METHOD

Renal damage was induced in the rats by administration of a single injection of CP at a dose of 150 mg/kg body weight intraperitoneally. For the AG pretreatment studies, the rats were injected intraperitoneally with AG at a dose of 200 mg/kg body weight 1 hour before administration of CP. The control rats received AG or saline alone. All the rats were killed 16 hours after the administration of CP or saline. The kidneys were used for histological examination by light microscopy and biochemical assays--malondialdehyde, protein carbonyl content, reduced glutathione (GSH), and the activities of antioxidant enzymes including glutathione peroxidase (GPx), glutathione S transferase (GSTase), catalase, glutathione reductase, and myeloperoxidase (MPO), a marker of neutrophil infiltration.

RESULTS

Pretreatment with AG attenuated CP-induced renal damage histologically. Pretreatment with AG prevented CP-induced lipid peroxidation, protein oxidation, depletion of reduced GSH, and loss of activities of the antioxidant enzymes including GPx, catalase, and GSTase and also MPO activity.

CONCLUSION

The results of the present study reveal that AG can prevent CP-induced renal damage by inhibiting oxidative stress. Thus, AG may be useful for prevention of the nephrotoxicity of CP.

Effect of Taurine on the antimicrobial efficiency of Gentamicin

CONTEXT

Gentamicin is mainly used in severe infections caused by gram-negatives. However toxicity including nephrotoxicity and ototoxicity is one of the most important complications of its treatment. The production of free radicals seems to be involved in gentamicin toxicity mechanism. Taurine, a major intracellular free β-amino acid, is known to be an endogenous antioxidant. So potentially the co-therapy of taurine and gentamicin would reduce the adverse effects of the antibiotic.

OBJECTIVES

In this study, we wished to know the effect of taurine on the antibiotic capacity of gentamicin.

METHODS

strainsof P. aeruginosa, E. coli, S. aureus and S. epidermidis were used as test organisms. Minimum inhibitory concentrations of gentamicin in the presence and absence of taurine at quantities from 40 to 2 mg/L were determined using macro-dilution method.

RESULTS

MICs were determined in the various concentrations of taurine for bacterial indicators. The MIC values of gentamicin for P. aeruginosa, S. aureus and E. coli remained unchanged in the values of 2.5, 5 and 20 μg/ml respectively in the absence and presences of different concentrations of taurine. The bactericidal activity of gentamicin against S. epidermidis was increased by addition of taurine in the concentrations higher than 6 mg/L.

CONCLUSION

According to our study the antibacterial activity of gentamicin against the indicator microorganisms were not interfere with taurine at selected concentrations. Further in vivo studies are needed to establish if a combination of gentamicin and taurine would have the same effect.