Curcumin, a diferuloylmethane, attenuates cyclosporine-induced renal dysfunction and oxidative stress in rat kidneys

Pomegranate attenuates kidney injury in cyclosporine-induced nephrotoxicity in rats by suppressing oxidative stress

To investigate the effect of pomegranate juice (PJ) on the cyclosporine (CsA)-induced nephrotoxicity in rats, 80 rats were divided into four groups. The first group was regarded a negative control group, and the others were as follows: group 2 (CsA group) received CsA in a dose of 25 mg/kg/day orally, group 3 (treated group) received CsA in a dose of 25 mg/kg/day plus 2.5 mL/day of PJ, and group 4 (PJ group) received 2.5 mL of PJ daily. By the end of the 21st day, plasma creatinine, blood urea nitrogen (BUN), creatinine clearance, urinary KIM-1, and NGAL were determined. Histopathological investigation and the determination of malondialdehyde and antioxidant enzymes were analyzed in kidney tissues. The results show that plasma creatinine, BUN, creatinine clearance, and kidney injury molecule-1 and neutrophil gelatinase-associated lipocalin were significantly altered in the CsA group. The supplement of PJ attenuated the alteration in these parameters. The treatment with PJ also prohibits the CsA-induced alteration in the histopathology, lipid peroxidation, and antioxidant enzymes. We can conclude that PJ protects against CsA-induced nephrotoxicity due to its antioxidant effects.

Nephroprotective effects of Candesartan Cilexetil against Cyclosporine A-induced nephrotoxicity in a rat model

Cyclosporine A (CsA), a well-known immunosuppressive drug, has been prescribed after organ transplantation and in a variety of disorders with an immunological origin. Nephrotoxicity is one of the most frequently stated problems associated with CsA, and therefore the treatment with CsA remains a big challenge. This study sets out to assess the ameliorative influences of Candesartan Cilexetil (CC) on oxidative stress and the nephrotoxic effect of CsA in a rat model. Twenty-four Wister Albino rats, 7-8-week-old, weighing 150-250g, were randomly categorized into three groups (eight animals in each group). These groups were the (1) CsA-treated group, (2) vehicle-treated group, and (3) CC-treated group. Bodyweights were assessed at the start and end of experiments. Renal function test and levels of glutathione peroxidase 1 catalase -CAT (Gpx1), catalase (CAT), superoxide dismutase (SOD), interleukin -2 (IL-2), and malondialdehyde (MDA) were investigated in renal tissues. Histological changes in kidneys were also evaluated. Data showed that levels of urea and creatinine in serum and levels of IL-2 and MDA in renal tissues were elevated in the CsA-treated group, with severe histological changes compared with the control group. Furthermore, tissue levels of Gpx1, CAT, and SOD were significantly decreased in CsA-treated in comparison with the control group. Treatment with CC for the rats subjected to CSA resulted in a marked reduction in levels of serum urea and creatinine and tissue levels of IL-2 and MDA. Levels of Gpx1, CAT, and SOD in renal tissues were greater in the CC-treatment group compared with the CsA-treated group. CC treatment reduced the deterioration of renal morphology compared with CsA treatment. The findings of this study suggest that CC could prevent CSA-induced nephrotoxicity through its anti-inflammatory and antioxidant influences. Considerably more work needs to be done to determine the mechanistic insight behind the ameliorative effect of CC.

Cyclosporine A Downregulates Selenoprotein P Expression via a Signal Transducer and Activator of Transcription 3-Forkhead Box Protein O1 Pathway in Hepatocytes In Vitro

Cyclosporine A (CsA) is an immunosuppressant applied worldwide for preventing graft rejection and autoimmune diseases. However, CsA elevates oxidative stress, which can lead to liver injuries. The present study aimed to clarify the mechanisms underlying the CsA-mediated oxidative stress. Among the redox proteins, CsA concentration-dependently downregulated Selenop-encoding selenoprotein P, a major circulating antioxidant protein reducing reactive oxygen species, in hepatocytes cell lines and primary hepatocytes. The luciferase assay identified the CsA-responsive element in the SELENOP promoter containing a putative binding site for forkhead box protein O (FoxO) 1. The CsA-mediated suppression on the SELENOP promoter was independent of the nuclear factor of activated T-cell, a classic target repressed by CsA. A chromatin immunoprecipitation assay showed that CsA suppressed the FoxO1 binding to the SELENOP promoter. Foxo1 knockdown significantly downregulated Selenop expression in H4IIEC3 cells. Furthermore, CsA downregulated FoxO1 by inactivating its upstream signal transducer and activator of transcription 3 (STAT3). Knockdown of Stat3 downregulated Foxo1 and Selenop expression in hepatocytes. These findings revealed a novel mechanism underlying CsA-induced oxidative stress by downregulating the STAT3-FoxO1-Selenop pathway in hepatocytes. SIGNIFICANCE STATEMENT: This study shows that Cyclosporine A (CsA) downregulates Selenop, an antioxidant protein, by suppressing the signal transducer and activator of transcription 3-forkhead box protein O1 pathway in hepatocytes, possibly one of the causations of CsA-induced oxidative stress in hepatocytes. The present study sheds light on the previously unrecognized CsA-redox axis.

2-Methoxyestradiol TPGS Micelles Attenuate Cyclosporine A-Induced Nephrotoxicity in Rats through Inhibition of TGF-β1 and p-ERK1/2 Axis

The immunosuppressant cyclosporine A (CSA) has been linked to serious renal toxic effects. Although 2-methoxyestradiol (2ME) possesses a wide range of pharmacological abilities, it suffers poor bioavailability after oral administration. The purpose of this study was to evaluate the potential of 2ME loaded D-ɑ-tocopheryl polyethylene glycol succinate (TPGS) micelles to prevent CSA-induced nephrotoxicity in rats. A 2ME-TPGS was prepared and showed particle size of 44.3 ± 3.5 nm with good entrapment efficiency and spherical structures. Male Wistar rats were divided into 5 groups, namely: Control, Vehicle, CSA, CSA + 2ME-Raw, and CSA + 2ME-Nano. CSA was injected daily at a SC dose of 20 mg/kg. Both 2ME-Raw and 2ME-Nano were given daily at oral doses of 5 mg/kg. Treatments continued for three successive weeks. 2ME-TPGS exerted significant protective effects against CSA nephrotoxicity. This was evidenced in ameliorating deterioration of renal functions, attenuation of pathological changes in kidney tissues, exerting significant anti-fibrotic, antioxidant, and anti-inflammatory effects together with significant anti-apoptotic effects. Western blot analyses showed both 2ME-Raw and 2ME-Nano significantly inhibited protein expression of TGF-β1 and phospho-ERK (p-ERK). It was observed that 2ME-TPGS, in almost all experiments, exerted superior protective effects as compared with 2ME-Raw. In conclusion, 2ME loaded in a TPGS nanocarrier possesses significant protective activities against CSA-induced kidney injury in rats. This is attributable to 2ME anti-fibrotic, antioxidant, anti-inflammatory, and anti-apoptotic activities which are mediated at least partly by inhibition of TGF-β1/p-ERK axis.

Cyclosporine A downregulates selenoprotein P expression via a STAT3-FoxO1 pathway in hepatocytes in vitro

Cyclosporine A (CsA) is a worldwide applied immunosuppressant for preventing graft rejection and autoimmune diseases. However, CsA elevates oxidative stress leading to liver injuries. The present study aimed to clarify the mechanisms underlying the CsA-mediated oxidative stress. Among the redox proteins, CsA concentration-dependently downregulated Selenop encoding selenoprotein P (SeP), a major circulating antioxidant protein reducing reactive oxygen species (ROS), in hepatocytes cell lines and primary hepatocytes. The luciferase assay identified the CsA-responsive element in the SELENOP promoter containing a putative binding site for FoxO1. The CsA-mediated suppression on the SELENOP promoter was independent of NFAT, a classic target repressed by CsA. A ChIP assay showed that CsA suppressed the FoxO1 binding to the SELENOP promoter. Foxo1 knockdown significantly downregulated Selenop expression in H4IIEC3 cells. Furthermore, CsA downregulated FoxO1 by inactivating its upstream signal transducer and activator of transcription 3 (STAT3). Knockdown of Stat3 downregulated Foxo1 and Selenop expression in hepatocytes. These findings revealed a novel mechanism underlying CsA-induced oxidative stress via downregulating the STAT3-FoxO1-Selenop pathway in hepatocytes. Significance Statement Our study shows that CsA downregulates Selenop, an antioxidant protein, via suppressing the STAT3-FoxO1 pathway in hepatocytes, possibly one of the causations of CsA-induced oxidative stress in hepatocytes. The present study sheds light on the previously unrecognized CsA-redox axis.

Curcumin Therapy to Treat Vascular Dysfunction in Children and Young Adults with ADPKD: A Randomized Controlled Trial

BACKGROUND AND OBJECTIVES

Clinical manifestations of autosomal dominant polycystic kidney disease (ADPKD), including evidence of vascular dysfunction, can begin in childhood. Curcumin is a polyphenol found in turmeric that reduces vascular dysfunction in rodent models and humans without ADPKD. It also slows kidney cystic progression in a murine model of ADPKD. We hypothesized that oral curcumin therapy would reduce vascular endothelial dysfunction and arterial stiffness in children/young adults with ADPKD.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

In a randomized, placebo-controlled, double-blind trial, 68 children/young adults 6-25 years of age with ADPKD and eGFR>80 ml/min per 1.73 m² were randomized to either curcumin supplementation (25 mg/kg body weight per day) or placebo administered in powder form for 12 months. The coprimary outcomes were brachial artery flow-mediated dilation and aortic pulse-wave velocity. We also assessed change in circulating/urine biomarkers of oxidative stress/inflammation and kidney growth (height-adjusted total kidney volume) by magnetic resonance imaging. In a subgroup of participants ≥18 years, vascular oxidative stress was measured as the change in brachial artery flow-mediated dilation following an acute infusion of ascorbic acid.

RESULTS

Enrolled participants were 18±5 (mean ± SD) years, 54% were girls, baseline brachial artery flow-mediated dilation was 9.3±4.1% change, and baseline aortic pulse-wave velocity was 512±94 cm/s. Fifty-seven participants completed the trial. Neither coprimary end point changed with curcumin (estimated change [95% confidence interval] for brachial artery flow-mediated dilation [percentage change]: curcumin: 1.14; 95% confidence interval, -0.84 to 3.13; placebo: 0.33; 95% confidence interval, -1.34 to 2.00; estimated difference for change: 0.81; 95% confidence interval, -1.21 to 2.84; P=0.48; aortic pulse-wave velocity [centimeters per second]: curcumin: 0.6; 95% confidence interval, -25.7 to 26.9; placebo: 6.5; 95% confidence interval, -20.4 to 33.5; estimated difference for change: -5.9; 95% confidence interval, -35.8 to 24.0; P=0.67; intent to treat). There was no curcumin-specific reduction in vascular oxidative stress or changes in mechanistic biomarkers. Height-adjusted total kidney volume also did not change as compared with placebo.

CONCLUSIONS

Curcumin supplementation does not improve vascular function or slow kidney growth in children/young adults with ADPKD.

CLINICAL TRIAL REGISTRY NAME AND REGISTRATION NUMBER

Curcumin Therapy to Treat Vascular Dysfunction in Children and Young Adults with ADPKD, NCT02494141.

PODCAST

This article contains a podcast at https://www.asn-online.org/media/podcast/CJASN/2022_02_07_CJN08950621.mp3.

Garlic Alleviates the Injurious Impact of Cyclosporine-A in Male Rats through Modulation of Fibrogenic and Steroidogenic Genes

This work aimed to study the hepato-testicular protective effect of garlic in rats treated with cyclosporine A (CsA). Forty male Westar albino rats were randomly distributed in five groups (8 rats each): control, olive oil, garlic, CsA, and CsA co-treated with garlic. CsA induced an upsurge in the alanine transaminase, aspartate transaminase, and alkaline phosphatase levels and decreased albumin and total protein levels, expression of superoxide dismutase (SOD) gene, serum testosterone, triiodothyronine, and thyroxine levels compared to the control group. Additionally, there was an increase in the cholesterol, triglyceride, and low-density lipoprotein levels and a substantial reduction in the high-density lipoprotein levels compared to the control groups. Histopathological investigation of the liver showed abnormalities like hepatic cell degeneration, congestion of blood vessels, and highly active Kupffer cells in the CsA group. Histopathological examination of testes showed damaged seminiferous tubules, stoppage of the maturation of spermatogonia, and the presence of cells with irregular dense nuclei in the lumina of some tubules. For the groups treated with garlic, mitigation of the damage caused by CsA in the liver and testes, liver function tests, lipid profiles, and hormones was seen along with improved gene expression of SOD and steroidogenesis genes, and decreased gene expression of collagen I-α1 and transforming growth factor-1β. Conclusively, garlic had a positive impact on CsA-induced hepatic and sperm toxicity. It is recommended that garlic should be supplemented in transplant treatments using CsA to alleviate the cyclosporin-induced oxidative injuries and other harmful effects.

Counteracting arsenic toxicity: Curcumin to the rescue?

Arsenicosis leads to various irreversible damages in several organs and is considered to be a carcinogen. The effects of chronic arsenic poisoning are a result of an imbalance between pro- and antioxidant homeostasis, oxidative stress, as well as DNA and protein damage. Curcumin, the polyphenolic pigment extracted from the rhizome of Curcuma longa, is well-known for its pleiotropic medicinal effects. Curcumin has been shown to have ameliorative effects in arsenic-induced genotoxicity, nephrotoxicity, hepatotoxicity, angiogenesis, skin diseases, reproductive toxicity, neurotoxicity, and immunotoxicity. This review aims to summarize the scientific evidence on arsenic toxicity in various organs and the ameliorative effects of curcumin on the arsenic toxicity.

Evaluation of ameliorative effect of two selected plant drugs on experimentally induced arsenic toxicity in sheep

Chronic arsenic poisoning is one of the serious health hazards in West Bengal, India, and Bangladesh. It occurs due to contaminated subsoil water. The aim of this study is conducted to find out the ameliorative effect of turmeric and P. foetida powder on experimentally induced arsenic toxicity in sheep. Twelve sheep were divided into four groups; groups I, II and III were orally administered with sodium arsenite at 6.6 mg/kg body weight for 133 days; groups I and II animals were treated by turmeric and P. foetida powders respectively at 500 mg/kg dose for the last 49 days; the fourth group was control. Arsenic content was estimated in faeces, urine and wool in every 15 days. Biochemical, haematological, antioxidant parameters and DNA fragmentation were also assessed. Turmeric and P. foetida powder treatment significantly (P < 0.05) increased arsenic elimination through faeces, urine and wool. Haemoglobin content and TEC were decreased in groups I, II and III; however, these were improved significantly (P < 0.05) by turmeric and P. foetida powder treatment. Increased activity of AST, ALT, blood urea nitrogen and plasma creatinine were significantly (P < 0.05) decreased in groups I and II. The reduced SOD and catalase activity were significantly (P < 0.05) restored at the end of the experiment in turmeric and P. foetida-treated groups. The test drugs are found significantly effective not only to eliminate arsenic from the body but also give protection from possible damage caused by arsenic exposure in sheep.

Curcumin alleviates OGD/R-induced PC12 cell damage via repressing CCL3 and inactivating TLR4/MyD88/MAPK/NF-κB to suppress inflammation and apoptosis

OBJECTIVES

Curcumin presents some therapeutic effects including anti-cancer and anti-inflammation. Herein, we centred on the functional role of curcumin in cerebral ischaemia injury and its potential molecular mechanisms.

METHODS

Microarray analysis was used for excavating crucial genes in cerebral ischaemia. PC12 cells were subjected to oxygen-glucose deprivation and reoxygenation (OGD/R) to imitate cerebral ischaemia/reperfusion (I/R) injury in vitro. Cell viability and apoptosis abilities were evaluated by Cell Counting Kit-8 and flow cytometry assays. qRT-PCR, Western blot and enzyme-linked immunosorbent assays were performed to assess the concentrations of related genes.

KEY FINDINGS

By enquiring GEO dataset, C-C motif chemokine ligand 3 (CCL3) was profoundly upregulated in cerebral I/R injury model. And CCL3 was found to be highly expressed in PC12 cells suffered from OGD/R. Moreover, we found that CCL3 was a potential target of curcumin in cerebral I/R injury. More importantly, the following experiments illustrated that curcumin inhibited the expression of CCL3 in OGD/R model and reduced cell apoptosis and inflammation. Moreover, high expression levels of TLR4, MyD88, p-NF-κB P65, p-P38 MAPK and p-IκBα in OGD/R model were inhibited by curcumin.

CONCLUSIONS

Our study manifested that curcumin might be a meritorious drug for the treatment of cerebral ischaemia by acting on CCL3.

Protective effects of pharmacological agents against aminoglycoside-induced nephrotoxicity: A systematic review

Introduction: Aminoglycosides have been long used for antibacterial treatment and are still commonly used in clinical practice. Despite their extensive application and positive effects, drug-related toxicity is considered as the main obstacle for aminoglycosides. Aminoglycosides induce nephrotoxicity through the endocytosis and accumulation of the antibiotics in the epithelial cells of proximal tubule. Most importantly, however, a number of pharmacological agents were demonstrated to have protective activities against nephrotoxicity in experimental animals.Areas covered: In the present systematic review, the authors provide and discuss the mechanisms and epidemiological features of aminoglycoside-induced nephrotoxicity, and focus mainly on recent discoveries and key features of pharmacological interventions. In total, 39 articles were included in this review.Expert opinion: The majority of studies investigated gentamicin-induced nephrotoxicity in animal models. Antioxidants, chemicals, synthetic drugs, hormones, vitamins, and minerals showed potential values to prevent gentamicin-induced nephrotoxicity. Indicators used to evaluate the effectiveness of nephroprotection included antioxidative indexes, inflammatory responses, and apoptotic markers. Among the nephroprotective agents studied, herbs and natural antioxidant agents showed excellent potential to provide a protective strategy against gentamicin-induced nephrotoxicity.

Chronic treatment of curcumin improves hepatic lipid metabolism and alleviates the renal damage in adenine-induced chronic kidney disease in Sprague-Dawley rats

Background

Chronic kidney disease (CKD), including nephrotic syndrome, is a major cause of cardiovascular morbidity and mortality. The literature indicates that CKD is associated with profound lipid disorders due to the dysregulation of lipoprotein metabolism which progresses kidney disease. The objective of this study is to evaluate the protective effects of curcumin on dyslipidaemia associated with adenine-induced chronic kidney disease in rats.

Methods

Male SD rats (n = 29) were divided into 5 groups for 24 days: normal control (n = 5, normal diet), CKD control (n = 6, 0.75% w/w adenine-supplemented diet), CUR 50 (n = 6, 50 mg/kg/day curcumin + 0.75% w/w adenine-supplemented diet), CUR 100 (n = 6, 100 mg/kg/day curcumin + 0.75% w/w adenine-supplemented diet), and CUR 150 (n = 6, 150 mg/kg/day curcumin + 0.75% w/w adenine-supplemented diet). The serum and tissue lipid profile, as well as the kidney function test, were measured using commercial diagnostic kits.

Results

The marked rise in total cholesterol, low-density lipoprotein (LDL) cholesterol, very low-density lipoprotein (VLDL) cholesterol, triglycerides and free fatty acids in serum, as well as hepatic cholesterol, triglyceride and free fatty acids of CKD control rats were significantly protected by curcumin co-treatment (at the dose of 50, 100 and 150 mg/kg). Furthermore, curcumin significantly increased the serum high-density lipoprotein (HDL) cholesterol compared to the CKD control rats but did not attenuate the CKD-induced weight retardation. Mathematical computational analysis revealed that curcumin significantly reduced indicators for the risk of atherosclerotic lesions (atherogenic index) and coronary atherogenesis (coronary risk index). In addition, curcumin improved kidney function as shown by the reduction in proteinuria and improvement in creatinine clearance.

Conclusion

The results provide new scientific evidence for the use of curcumin in CKD-associated dyslipidaemia and substantiates the traditional use of curcumin in preventing kidney damage.

Efficacy of curcumin on prevention of drug-induced nephrotoxicity: A review of animal studies

Drug-induced nephrotoxicity is a frequent serious adverse effect, contributing to morbidity and increased healthcare utilization. Prevention or reversal is key. Curcumin has useful biological features that include antioxidant, anti-inflammatory, and anticancer properties. This review covers aspects of curcumin in relation to prevention of drug-induced nephrotoxicity: dosage and schedule, effect on kidney biomarkers and histological changes, and mechanisms of curcumin's protective effects. Despite success in some animal models, human studies and clinical administration of curcumin for nephroprotection remains limited due to difficulty in achieving therapeutic levels following oral administration and in determining the optimal dosing schedule. Lack of sufficient evidence from animal studies, coupled with low systemic bioavailability, continues to limit the utilization of curcumin in addressing and controlling drug-induced nephrotoxicity. Therefore, human studies are required to fully assess and validate the therapeutic potential of curcumin.

Effects of Curcumin on Vessel Formation Insight into the Pro- and Antiangiogenesis of Curcumin

Curcumin is a compound extracted from the Curcuma longa L, which possesses a wide range of pharmacological effects. However, few studies have collected scientific evidence on its dual effect on angiogenesis. The present review gathered the fragmented information available in the literature to discuss the dual effect and possible mechanisms of curcumin on angiogenesis. Available information concerning the effect of curcumin on angiogenesis is compiled from scientific databases, including PubMed and Web of Science using the key term (curcumin and angiogenesis). The results were reviewed to identify relevant articles. Related literature demonstrated that curcumin has antiangiogenesis effect via regulating multiple factors, including proangiogenesis factor VEGF, MMPs, and FGF, both in vivo and in vitro, and could promote angiogenesis under certain circumstances via these factors. This paper provided a short review on bidirectional action of curcumin, which should be useful for further study and application of this compound that require further studies.

Epigenetic regulation in AKI and kidney repair: mechanisms and therapeutic implications

Acute kidney injury (AKI) is a major public health concern associated with high morbidity and mortality. Despite decades of research, the pathogenesis of AKI remains incompletely understood and effective therapies are lacking. An increasing body of evidence suggests a role for epigenetic regulation in the process of AKI and kidney repair, involving remarkable changes in histone modifications, DNA methylation and the expression of various non-coding RNAs. For instance, increases in levels of histone acetylation seem to protect kidneys from AKI and promote kidney repair. AKI is also associated with changes in genome-wide and gene-specific DNA methylation; however, the role and regulation of DNA methylation in kidney injury and repair remains largely elusive. MicroRNAs have been studied quite extensively in AKI, and a plethora of specific microRNAs have been implicated in the pathogenesis of AKI. Emerging research suggests potential for microRNAs as novel diagnostic biomarkers of AKI. Further investigation into these epigenetic mechanisms will not only generate novel insights into the mechanisms of AKI and kidney repair but also might lead to new strategies for the diagnosis and therapy of this disease.

Microfluidic manufacturing of different niosomes nanoparticles for curcumin encapsulation: Physical characteristics, encapsulation efficacy, and drug release

Curcumin, a natural chemical compound found in Curcuma longa that has been used in antitumor and anti-inflammation applications, exhibits very limited water solubility and rapid in vivo degradation, which limits its clinical application. To overcome these limitations, niosome nanoparticles were prepared by microfluidic mixing for curcumin encapsulation. Niosome nanoparticles are lipid-based, and composed of non-ionic surfactants with cholesterol orientated into a membrane bilayer structure. Two different non-ionic surfactants were used and the mixing parameters were varied to optimize the characteristics of the prepared niosomes. The prepared niosomes had an average particle size of 70-230 nm depending on the type of non-ionic surfactant used and the mixing parameter. Moreover, all prepared niosomes were monodisperse with an average polydispersity index ranging from 0.07 to 0.3. All prepared niosomes were spherical as demonstrated by transmission electron microscopy. Curcumin was encapsulated with a maximum encapsulation efficiency of around 60% using Tween 85 as the non-ionic surfactant. Niosomes prepared by microfluidic mixing provided a controlled release of curcumin, as indicated by the release profile of curcumin, improving its therapeutic capability. These results demonstrate that niosomes prepared by microfluidic mixing to encapsulate curcumin are a promising delivery system to reach target cells.

N-acetylcysteine protects against diabetic nephropathy through control of oxidative and nitrosative stress by recovery of nitric oxide in rats

The diabetes mellitus (DM) induces several changes, with substantial increase of reactive oxygen species (ROS). The ROS cause damage to systemic and renal microvasculature, which could be one of the mechanisms involved in the development of diabetic nephropathy (DN). The ROS modulate other substances like the nitric oxide (NO), a vasodilator with important role in the renal function. N-acetylcysteine (NAC) is an antioxidant that acts replenishing intracellular cysteine levels, which is essential for glutathione formation. The aim of this study was to evaluate the effect of early or late NAC treatment on oxidative/nitrosative stress in DN progression. All rats were submitted to unilateral nephrectomy and diabetes was induced with streptozotocin. The animals were allocated into six groups: controls that received water (CTL) or NAC (CTL + NAC); diabetic groups that received early or late, water (DM-E; DM-L) or NAC (DM + NAC-E; DM + NAC-L), started on 5th day (early) or 4th week (late) after diabetes induction, during 8 weeks. After NAC treatment, the rats were placed in individual metabolic cages to obtain urine and blood samples for analysis of metabolic profile, renal function, thiobarbituric acid reactive substances (TBARS) and NO. At the end of the protocol, the renal cortex was removed for TBARS, NOS evaluation, antioxidants markers and histology. The DM-E group compared to CTL showed a significant increase in glycemia and proteinuria and impaired renal function; there was a significant increase of TBARS in plasma, urine and renal tissue, and also a significant decrease in plasma NO, which were reverted after early NAC treatment. The eNOS was decreased and iNOS was increased in DM-E vs. CTL, p < 0.05. The early NAC treatment in DM rats reduced proteinuria, creatinine, urea, TBARS and iNOS and, increased creatinine clearance, NO and eNOS, increasing significantly the antioxidant defenses, promoting elevated catalase and glutathione compared to DM-E group, all p < 0.05. The late NAC treatment in diabetic rats vs.DM-E showed reduced proteinuria and TBARS excretion and higher values of creatinine clearance and NO, all statistically significant. Histological analysis of the animals in DM-E or DM-L showed significant tubular changes with degeneration and vacuolization in tubular cells, dilated tubular lumen, intense glycosidic degeneration, and discreet mesangial expansion with interstitial fibrosis area. The DM + NAC-E group showed moderate glycosidic degeneration, however, did not present tubular degeneration or fibrosis. The DM + NAC-L group showed severe glycosidic degeneration, moderate tubular cell degeneration, light and focal dilatation of the tubules, with no fibrosis. Our study showed that NAC protected the diabetic rats against renal injury, probably due to the control of oxidative stress via recovery of the NO bioavailability, showing that early NAC was more effective than late treatment. All these data suggest that NAC may be useful in the adjuvant treatment in a safe way, in the early phase of the disease. Eventually, prolonged treatment, even if it is started later, could change the natural history of the disease, delaying the complications of diabetes in renal tissue.

Molecular Mechanisms of Curcumin Renoprotection in Experimental Acute Renal Injury

As a highly perfused organ, the kidney is especially sensitive to ischemia and reperfusion. Ischemia-reperfusion (IR)-induced acute kidney injury (AKI) has a high incidence during the perioperative period in the clinic and is an important link in ischemic acute renal failure (IARF). Therefore, IR-induced AKI has important clinical significance and it is necessary to explore to develop drugs to prevent and alleviate IR-induced AKI. Curcumin [diferuloylmethane, 1,7-bis(4-hydroxy-3-methoxiphenyl)-1,6-heptadiene-3,5-dione)] is a polyphenol compound derived from Curcuma longa (turmeric) and was shown to have a renoprotective effect on ischemia-reperfusion injury (IRI) in a previous study. However, the specific mechanisms underlying the protective role of curcumin in IR-induced AKI are not completely understood. APPL1 is a protein coding gene that has been shown to be involved in the crosstalk between the adiponectin-signaling and insulin-signaling pathways. In the study, to investigate the molecular mechanisms of curcumin effects in kidney ischemia/reperfusion model, we observed the effect of curcumin in experimental models of IR-induced AKI and we found that curcumin treatment significantly increased the expression of APPL1 and inhibited the activation of Akt after IR treatment in the kidney. Our in vitro results showed that apoptosis of renal tubular epithelial cells was exacerbated with hypoxia-reoxygenation (HR) treatment compared to sham control cells. Curcumin significantly decreased the rate of apoptosis in renal tubular epithelial cells with HR treatment. Moreover, knockdown of APPL1 activated Akt and subsequently aggravated apoptosis in HR-treated renal tubular epithelial cells. Conversely, inhibition of Akt directly reversed the effects of APPL1 knockdown. In summary, our study demonstrated that curcumin mediated upregulation of APPL1 protects against ischemia reperfusion induced AKI by inhibiting Akt phosphorylation.

Comparison of the Efficacy of Topical Triamcinolone in Orabase and Curcumin in Orabase in Oral Graft-Versus-Host Disease

OBJECTIVES

Graft-versus-host disease (GVHD) is among the most frequent complications of allogeneic hematopoietic stem cell transplantation (HSCT). GVHD has several clinical manifestations in the oral cavity, including painful desquamative erythema, ulcerative mucosal lesions, and lichenoid lesions. The patients presenting with oral GVHD complain of oral sensitivity, pain, dysgeusia, and xerostomia. The treatment of oral GVHD includes a proper systemic therapy combined with a good oral hygiene and the use of local and topical steroids. Corticosteroids and immunosuppressants are used for the treatment of chronic oral GVHD; however, they are associated with different complications. Evidence shows that curcumin has anti-inflammatory and antioxidative properties. The treatment of lichen planus and oral mucositis with curcumin has been successful. This study aimed to compare the efficacy of topical curcumin in Orabase and triamcinolone in Orabase in the patients affected by oral GVHD.

MATERIALS AND METHODS

Twenty-six patients presenting with oral GVHD were randomly divided into two groups of 13 using block randomization. The control group used triamcinolone in Orabase, and the case group received curcumin in Orabase.

RESULTS

The two groups were not significantly different in terms of the alleviated severity of the lesions at the end of the treatment (P=0.052). The comparison of the pain score via the visual analog scale (VAS) at the onset of the treatment and at days 14 and 28 (completion of the treatment) showed no significant difference between the two groups (P>0.05).

CONCLUSIONS

Curcumin has comparable efficacy to that of triamcinolone and may be prescribed for the patients presenting with oral GVHD.

Modulatory effect of curcumin against genotoxicity and oxidative stress induced by cisplatin and methotrexate in male mice

The use of dietary antioxidants to modulate the toxic side effects induced by the anticancer drugs used in chemotherapy is currently eliciting considerable interest. This study was undertaken to investigate the possible protective role of the antioxidant curcumin (CMN) against genotoxicity, cytotoxicity and oxidative stress induced by cisplatin and methotrexate. Male mice were administered CMN orally in the dosages of 60, 90, and 120 mg/kg for three consecutive days before a single intraperitoneal injection of either cisplatin (6.5 mg/kg) or methotrexate (10 mg/kg). Animals were sacrificed 24 h after treatment with the used anticancer drugs. The protective role of CMN against the genotoxic and cytotoxic effects of the tested anticancer drugs was evaluated by using micronucleus and comet assay. The oxidative stress induced by the two anticancer drugs was assessed by determining malondialdehyde and reduced glutathione levels in kidney tissues. The results indicated that CMN pretreatment at the tested doses reduced the incidence of micronuclei and DNA damage induced by cisplatin and methotrexate. Moreover, malondialdhyde level was significantly decreased while glutathione level was significantly increased in CMN pretreated groups compared with cisplatin- and methotrexate-treated groups. This protective effect of CMN could be attributed to its ability to scavenge reactive oxygen species.

Ameliorative effect of two Ayurvedic herbs on experimentally induced arsenic toxicity in calves

ETHNOPHARMACOLOGICAL RELEVANCE

Chronic arsenic poisoning due to contaminated subsoil water is a threat to society in West Bengal, India and in Bangladesh. The human being may also be affected by the exposed cattle from the affected area by consuming milk, egg, meat and others. In Ayurveda, several herbs like Haridra (turmeric), Shunthi (dried ginger root) and others are used for the management of arsenic poisoning.

AIM OF THE STUDY

The study was conducted to find out the ameliorative effect of turmeric and ginger powder against experimentally induced arsenic toxicity in calves.

MATERIALS AND METHODS

Twenty four calves were divided into four groups (group I, II, III and IV) having six animals in each group. Animals of group I, II and III were orally administered with sodium arsenite at 1mg/kg body weight for 90 days and in addition group II and group III animals were treated orally with turmeric and ginger powder respectively at 10mg/kg body weight from 46th day onwards. Group IV animals were given food and water without drug and served as control. Arsenic content was estimated in faeces, hair, urine and plasma in every 15 days. Bio-chemical, haematological and anti-oxidant parameters were also assessed.

RESULTS

Turmeric and ginger powder significantly (P<0.05) reduced the plasma and hair arsenic levels through increased excretion via faeces and urine. Haemoglobin level, TEC and TLC were decreased in groups I, II and III, however these were improved significantly (P<0.05) from 75th day onwards in turmeric and ginger treated groups. Increased activity of AST and ALT were significantly decreased (P<0.05) from 75th day onwards in group II and III. Blood urea nitrogen and plasma creatinine were also significantly decreased (P<0.05) in group II and III than group I from 60th day onwards. The SOD and catalase activity were significantly (P<0.05) reduced in groups I, II and III, but these were restored at the end of the experiment in turmeric and ginger treated groups.

CONCLUSION

The test drugs are found significantly effective not only to eliminate arsenic from the body but also give protection from possible damage caused by arsenic exposure, it may be concluded from the present study that turmeric and ginger can be helpful in the therapy of chronic arsenic toxicity in calves.

Can curcumin modulate allergic rhinitis in rats?

OBJECTIVES

This study aimed to explore the effects of curcumin on experimental allergic rhinitis in rats.

METHODS

Twenty-eight male Wistar albino rats were randomly divided into four groups: a control group; a group in which allergic rhinitis was induced and no treatment given; a group in which allergic rhinitis was induced followed by treatment with azelastine hydrochloride on days 21-28; and a group in which allergic rhinitis was induced followed by treatment with curcumin on days 21-28. Allergy symptoms and histopathological features of the nasal mucosa were examined.

RESULTS

The sneezing and nasal congestion scores were higher in the azelastine and curcumin treatment groups than in the control group. Histopathological examination showed focal goblet cell metaplasia on the epithelial surface in the azelastine group. In the curcumin group, there was a decrease in goblet cell metaplasia in the epithelium, decreased inflammatory cell infiltration and vascular proliferation in the lamina propria.

CONCLUSION

Curcumin is an effective treatment for experimentally induced allergic rhinitis in rats.

Hepatoprotective and Nephroprotective Effect of Curcumin Against Copper Toxicity in Rats

Curcumin is a natural anti-inflammatory and antioxidant with several potential health benefits. Although it has been examined in several metals toxicity studies, but its role in the protection against copper toxicity has not been investigated. In this study; the detoxification and antioxidant effect of curcumin were examined to determine its prophylactic/therapeutic role experimentally in rats. Forty albino rats were divided into five groups; control, CuSO4 (4 mg/kg body weight), curcumin (80 mg/kg body weight), curcumin post-treatment (CuSO4 for 15 days followed by curcumin for the next 15 days) and curcumin co-treatment (CuSO4 plus curcumin for 30 days). All rats were treated orally by stomach tube for 30 days/once a day. Changes were observed in hepatic marker enzymes such as: aspartate aminotransferase (AST), alanine transaminase-(ALT), alkaline phosphatase (ALP) and gamma-glutamyltransferase (GGT), besides the serum total protein, urea and creatinine. Concentration of liver and kidney antioxidants such as: catalase (CAT), superoxide dismutase (SOD), reduced glutathione-(GSH) and malondialdehyde (MDA) were measured. An increased in the activities of liver marker enzymes, urea, creatinine and the MDA contents were detected after exposure to CuSO4. Meanwhile, the activities of serum total protein, hepatic and renal antioxidants were decreased. Changes in all biochemical parameters were alleviated by the post-treatment and co-treatment of curcumin. Our finding suggests that the curcumin showed protective effects on CuSO4-induced hepatotoxicity and nephrotoxicity.

Cinnamaldehyde is an effective anti-inflammatory agent for treatment of allergic rhinitis in a rat model

OBJECTIVES

The effect of cinnamaldehyde on the treatment of allergic rhinitis (AR) was investigated in rat model.

METHODS

Twenty-eight female Wistar albino rats were randomly divided into four groups: Group 1 (control) (C), Group 2 (AR with no treatment) (AR+NoTr), Group 3 (AR+Azelastine HCl) (AR+Aze), and Group 4 (AR+cinnamaldehyde) (AR+Cin). At day 21, AR+Aze rats were given an Azelastine HCl drop, and AR+Cin rats were given cinnamaldehyde intranasally. In all groups, allergic symptoms histopathological results were evaluated.

RESULTS

The AR+NoTr group showed the worst allergic symptoms, cilia loss and greater inflammation. In the AR+Aze and AR+Cin groups, allergic symptom scores were higher than those in the control group. However, between AR+Aze and AR+Cin groups, there were no significant differences in the allergic symptom scores Histopathological analysis revealed vascular congestion and an increase in goblet cell numbers in the AR+Cin group. However, AR+Cin rat nasal mucosa had less plasma cell infiltration compared with the AR+NoTr group. In rats from the AR+Aze group, analysis of the nasal mucosa revealed less eosinophil infiltration than that seen in the AR+NoTr group. A lower score for mast cell (MC) infiltration was observed in the nasal mucosa of rats treated with Azelastine HCl compared with cinnamaldehyde.

CONCLUSIONS

In this study we observed that both Azelastine HCl and cinnamaldehyde reduced allergic symptoms in an AR rat model. Cinnamaldehyde decreased vascular congestion as well as plasma cell, eosinophil, and inflammatory cell infiltration into the lamina propria.

Effect of retinyl acetate on transglutaminase 2 activity in carcinogen treated rat liver

Transglutaminase 2 (TG2) has been implicated in wound healing, cellular differentiation, apoptosis and cell survival. TG2 activity increases following acute and chronic liver injury; however, the role of TG2 in tumors, is controversial. TG2 is a retinoid-inducible enzyme. We investigated the effects of retinyl acetate (RA) on the activity and levels of TG2 during the initiation and promotion stages of liver cancer. p-Dimethylaminoazobenzene (p-DAB) was used as initiator and 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin (TCDD) was used as promoter in our model of carcinogenesis. Rats were divided into four groups of 24: control, corn oil control, p-DAB + TCDD, and p-DAB + TCDD + RA. Six rats from each group were sacrificed at days 30, 60, 90 and 120. TG2 activity decreased in the p-DAB + TCDD treated group, but TG2 immunostaining scores did not change by days 90 and 120. Neither TG2 enzyme activity nor the immunostaining score of TG2 protein changed in the tissues of the p-DAB + TCDD + RA group by days 90 and 120. TG2 activity was not be ameliorated by RA during the initiation or promotion stages of carcinogen induced liver cancer.

Effects of curcumin on the social behavior, blood composition, reproductive hormones in plasma and brain acetylcholinesterase in cadmium intoxicated mice

Cadmium (Cd) exposure can induce acute lethal health-related threats in humans since it has an exceptional ability to accumulate in living organism tissues and cause toxicological effects. Curcumin (Cur) on the other hand has a wide variety of biological activities and several studies have suggested its potential therapeutic or protective effects against several ailments and infections. To study the effect of Cur on the toxicity of Cd, Swiss-Webster strain male and female mice (sixty each) were divided into 6 groups of ten each at random. Group-1 served as the naïve control and received no treatment. Group-2, 3 and 4 were the experimental controls and were administered once a day with a single oral dose of 50% dimethyl sulfoxide (DMSO), Cur (300 mg/kg) or Cd (100 mg/kg) respectively, for 2 weeks. Group-5 and 6 received Cur and Cd in combination once a day orally for 2 weeks except that Cur in a dose of 150 and 300 mg/kg to group 5 and 6 respectively, was administered one hour before Cd administration to both groups. After treatment period, the male animals were subjected to social standard opponent test and females were subjected to the tube restraint tests and thereafter, their blood was collected to measure the blood composition indices and level of reproductive hormones. The animals were sacrificed to collect their brain for the estimation of acetylcholinesterase (AChE). Results indicated that Cd significantly increased nonsocial activities in males and latency to first bite in females, whereas the social activities in males and the number of bites in females were significantly decreased. All measured indices of blood composition and levels of progesterone (female) and testosterone (male) in blood and AChE in their brain tissues were significantly decreased due to Cd treatment. However, administration of Cur along with Cd had an ameliorating effect on all the behavioral and biochemical parameters studied herein and reduced the toxicity of Cd significantly and dose-dependently. Thus, Cur may be beneficial for general health and for protection from Cd intoxication.

Curcumin Nanoformulation for Cervical Cancer Treatment

Cervical cancer is one of the most common cancers among women worldwide. Current standards of care for cervical cancer includes surgery, radiation, and chemotherapy. Conventional chemotherapy fails to elicit therapeutic responses and causes severe systemic toxicity. Thus, developing a natural product based, safe treatment modality would be a highly viable option. Curcumin (CUR) is a well-known natural compound, which exhibits excellent anti-cancer potential by regulating many proliferative, oncogenic, and chemo-resistance associated genes/proteins. However, due to rapid degradation and poor bioavailability, its translational and clinical use has been limited. To improve these clinically relevant parameters, we report a poly(lactic-co-glycolic acid) based curcumin nanoparticle formulation (Nano-CUR). This study demonstrates that in comparison to free CUR, Nano-CUR effectively inhibits cell growth, induces apoptosis, and arrests the cell cycle in cervical cancer cell lines. Nano-CUR treatment modulated entities such as miRNAs, transcription factors, and proteins associated with carcinogenesis. Moreover, Nano-CUR effectively reduced the tumor burden in a pre-clinical orthotopic mouse model of cervical cancer by decreasing oncogenic miRNA-21, suppressing nuclear β-catenin, and abrogating expression of E6/E7 HPV oncoproteins including smoking compound benzo[a]pyrene (BaP) induced E6/E7 and IL-6 expression. These superior pre-clinical data suggest that Nano-CUR may be an effective therapeutic modality for cervical cancer.

Sustained proliferation in cancer: Mechanisms and novel therapeutic targets

Proliferation is an important part of cancer development and progression. This is manifest by altered expression and/or activity of cell cycle related proteins. Constitutive activation of many signal transduction pathways also stimulates cell growth. Early steps in tumor development are associated with a fibrogenic response and the development of a hypoxic environment which favors the survival and proliferation of cancer stem cells. Part of the survival strategy of cancer stem cells may manifested by alterations in cell metabolism. Once tumors appear, growth and metastasis may be supported by overproduction of appropriate hormones (in hormonally dependent cancers), by promoting angiogenesis, by undergoing epithelial to mesenchymal transition, by triggering autophagy, and by taking cues from surrounding stromal cells. A number of natural compounds (e.g., curcumin, resveratrol, indole-3-carbinol, brassinin, sulforaphane, epigallocatechin-3-gallate, genistein, ellagitannins, lycopene and quercetin) have been found to inhibit one or more pathways that contribute to proliferation (e.g., hypoxia inducible factor 1, nuclear factor kappa B, phosphoinositide 3 kinase/Akt, insulin-like growth factor receptor 1, Wnt, cell cycle associated proteins, as well as androgen and estrogen receptor signaling). These data, in combination with bioinformatics analyses, will be very important for identifying signaling pathways and molecular targets that may provide early diagnostic markers and/or critical targets for the development of new drugs or drug combinations that block tumor formation and progression.

Inhalable curcumin: offering the potential for translation to imaging and treatment of Alzheimer's disease

Curcumin is a promising compound that can be used as a theranostic agent to aid research in Alzheimer's disease. Beyond its ability to bind to amyloid plaques, the compound can also cross the blood-brain barrier. Presently, curcumin can be applied only to animal models, as the formulation needed for iv injection renders it unfit for human use. Here, we describe a novel technique to aerosolize a curcumin derivative, FMeC1, and facilitate its safe delivery to the brain. Aside from the translational applicability of this approach, a study in the 5XFAD mouse model suggested that inhalation exposure to an aerosolized FMeC1 modestly improved the distribution of the compound in the brain. Additionally, immunohistochemistry data confirms that following aerosol delivery, FMeC1 binds amyloid plaques expressed in the hippocampal areas and cortex.

Effects of antioxidant agents against cyclosporine-induced hepatotoxicity

BACKGROUND

To investigate the potential protective antioxidant role of ursodeoxycholic acid (UDCA), melatonin, and allopurinol treatment in cyclosporine (CsA)-induced hepatotoxicity.

METHODS

Hepatotoxicity was established in Sprague-Dawley rats by daily administration of CsA. Treatment groups were additionally administered UDCA, melatonin, or allopurinol treatments. Rats that received no CsA and no treatments served as a control group. Liver samples from each group were examined by histopathologic analysis to determine the effects of CsA treatment on liver morphology. Biochemical assays were also used to determine the effect of CsA treatment on liver function, in the presence or absence of UDCA, melatonin, or allopurinol.

RESULTS

CsA treatment induced hepatotoxicity, resulting in sinusoidal dilatation, congestion, infiltration, hydropic degeneration, and loss of glycogen storage in the liver. From a molecular perspective, the CsA treatment increased levels of malondialdehyde (MDA) levels, decreased levels of reduced glutathione and xanthine oxidase, and decreased activities of superoxide dismutase and catalase. The CsA treatment also resulted in decreased serum total antioxidant capacity, whereas alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, total bilirubin levels, and total oxidant status were increased. Treatment with UDCA, melatonin, or allopurinol reduced the CsA-induced histopathologic changes, as compared with CsA-treated samples. In addition, UDCA, melatonin, or allopurinol treatment mitigated the CsA-induced effects on glutathione and MDA levels, and on superoxide dismutase and catalase activities, as well as reduced the CsA-mediated perturbations in serum levels of total antioxidant capacity, total oxidant status, and alkaline phosphatase.

CONCLUSIONS

UDCA, allopurinol, and melatonin may each help to protect against CsA-induced damage to liver tissues, possibly through effects on the antioxidant system.

Protective effects of phyllanthus emblica leaf extract on sodium arsenite-mediated adverse effects in mice

Groundwater contamination of arsenic is the major cause of a serious health hazard in Bangladesh. No specific treatment is yet available to manage the large number of individuals exposed to arsenic. In this study, we evaluated the protective effects of Phyllanthus emblica (Indian gooseberry or Amla) leaf extract (PLE) on arsenic-mediated toxicity in experimental mice. Male Swiss albino mice were divided into three different groups (n=6/group). 'Control' mice received arsenic free water together with normal feed. Mice in the remaining two groups designated 'SA' and 'SA+PLE' were exposed to sodium arsenite (SA, 10 µg/g body weight/day) through drinking water in addition to receiving normal feed and PLE-supplemented feed, respectively. The weight gain of SA-exposed mice was decreased compared with the controls; however, this decrease in body weight gain was prevented when the feed was supplemented with PLE. A secondary effect of arsenic was enlargement of the liver, kidney and spleen of SA-group mice. Deposition of arsenic in those organs was demonstrated by ICP-MS. When PLE was supplemented in the feed the enlargement of the organs was minimized; however, the deposition of arsenic was not significantly reduced. These results indicated that PLE may not block arsenic deposition in tissue directly but rather may play a protective role to reduce arsenic-induced toxicity. Therefore, co-administration of PLE in arsenic-exposed animals might have a future therapeutic application for protecting against arsenic-mediated toxicity.

Cyclosporine A loaded self-nanoemulsifying drug delivery system (SNEDDS): implication of a functional excipient based co-encapsulation strategy on oral bioavailability and nephrotoxicity

The present work focusses on the formulation development and evaluation of a functional excipient, a vitamin E TPGS loaded self-nanoemulsifying drug delivery system, for improving the deliverability and safety profile of cyclosporine A.

Therapeutic effects of curcumin on the functional disturbances and oxidative stress induced by renal ischemia/reperfusion in rats

OBJECTIVE

Curcumin has anti-inflammatory and antioxidative properties. The objective of this study was to investigate the therapeutic effects of curcumin on functional disturbances, oxidative stress, and leukocyte infiltration induced by renal ischemia/reperfusion (I/R).

MATERIALS AND METHODS

Animals were randomly divided into 9 groups. The groups with 24-h reperfusion consisted of sham-24h, I/R-24h, and three I/R groups treated with curcumin at 10, 20, or 30 mg kg(-1), i.p. after the ischemic period. The 72-h reperfusion groups also included Sham-72h, I/R-72h, I/R treated with curcumin at single dose of 20 mg kg(-1), i.p., and I/R group which received three doses of curcumin at 20 mg kg(-1), i.p., consecutively. Renal functional injury was assessed by measuring serum creatinine and urea-nitrogen concentrations. Oxidative stress was evaluated by assessment tissue malondialdehyde (MDA) and the ferric reducing/antioxidant power (FRAP) levels. Moreover, renal tissue leukocyte infiltration was measured by histopathology examination.

RESULTS

Ischemia/reperfusion resulted in a significant increase in serum concentration of creatinine, urea-nitrogen, tissue MDA level, and leukocytes infiltration as well as reduced FRAP level. Treatment with curcumin in 24-h reperfusion groups could only lead to a significant change in the levels of MDA and FRAP. However, in 72-h reperfusion groups, curcumin was able to correct all functional disturbances, oxidative stress, and leukocytes infiltration with more effectiveness in groups that received three doses of curcumin.

CONCLUSION

The administration of curcumin during 72-h reperfusion following 30 minutes of ischemia can decrease renal oxidative stress and leukocytes infiltration as well as improve kidney function. However, during first 24-h reperfusion, curcumin only decreased oxidative stress.

CCl4 induced genotoxicity and DNA oxidative damages in rats: hepatoprotective effect of Sonchus arvensis

BACKGROUND

Sonchus arvesis is traditionally reported in various human ailments including hepatotoxicity in Pakistan. Presently we designed to assess the protective effects of methanolic extract of Sonchus arvesis against carbon tetrachloride induced genotoxicity and DNA oxidative damages in hepatic tissues of experimental rats.

METHODS

36 male Sprague-Dawley rats were randomly divided into 6 groups to evaluate the hepatoprotective effects of Sonchus arvensis against CCl4 induced genotoxicity, DNA damages and antioxidant depletion. Rats of normal control group were given free access of food and water add labitum. Group II rats received 3 ml/kg of CCl4 (30% in olive oil v/v) via the intraperitoneal route twice a week for four weeks. Group III and IV received 1 ml of 100 mg/kg b.w. and 200 mg/kg b.w. SME via gavage after 48 h of CCl4 treatment whereas group V was given 1 ml of silymarin (100 mg/kg b.w.) after 48 h of CCl4 treatment. Group VI only received 200 mg/kg b.w. SME. Protective effects of SME were checked by measuring serum markers, activities of antioxidant enzymes, genotoxicity and DNA dmages.

RESULTS

Results of the present study showed that treatment of SME reversed the activities of serum marker enzymes and cholesterol profile as depleted with CCl4 treatment. Activities of endogenous antioxidant enzymes of liver tissue homogenate; catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GSHpx), glutathione-S-transferase (GST) and glutathione reductase (GSR) were reduced with administration of CCl4, which were returned to the control level with SME treatment. CCl4-induced hepatic cirrhosis decreased hepatic glutathione (GSH) and increased lipid peroxidative products (TBARS), were normalized by treatment with SME. Moreover, administration of CCl4 caused genotoxicity and DNA fragmentation which were significantly restored towards the normal level with SME.

CONCLUSION

These results reveal that treatment of SME may be useful in the prevention of hepatic stress.

Curcumin prevents maleate-induced nephrotoxicity: relation to hemodynamic alterations, oxidative stress, mitochondrial oxygen consumption and activity of respiratory complex I

The potential protective effect of the dietary antioxidant curcumin (120 mg/Kg/day for 6 days) against the renal injury induced by maleate was evaluated. Tubular proteinuria and oxidative stress were induced by a single injection of maleate (400 mg/kg) in rats. Maleate-induced renal injury included increase in renal vascular resistance and in the urinary excretion of total protein, glucose, sodium, neutrophil gelatinase-associated lipocalin (NGAL) and N-acetyl β-D-glucosaminidase (NAG), upregulation of kidney injury molecule (KIM)-1, decrease in renal blood flow and claudin-2 expression besides of necrosis and apoptosis of tubular cells on 24 h. Oxidative stress was determined by measuring the oxidation of lipids and proteins and diminution in renal Nrf2 levels. Studies were also conducted in renal epithelial LLC-PK1 cells and in mitochondria isolated from kidneys of all the experimental groups. Maleate induced cell damage and reactive oxygen species (ROS) production in LLC-PK1 cells in culture. In addition, maleate treatment reduced oxygen consumption in ADP-stimulated mitochondria and diminished respiratory control index when using malate/glutamate as substrate. The activities of both complex I and aconitase were also diminished. All the above-described alterations were prevented by curcumin. It is concluded that curcumin is able to attenuate in vivo maleate-induced nephropathy and in vitro cell damage. The in vivo protection was associated to the prevention of oxidative stress and preservation of mitochondrial oxygen consumption and activity of respiratory complex I, and the in vitro protection was associated to the prevention of ROS production.

P2X(7) receptor in the kidneys of diabetic rats submitted to aerobic training or to N-acetylcysteine supplementation [corrected]

Previous studies in our laboratory showed that N-acetylcysteine supplementation or aerobic training reduced oxidative stress and the progression of diabetic nephropathy in rats. The P2X₇ receptor is up-regulated in pathological conditions, such as diabetes mellitus. This up-regulation is related to oxidative stress and induces tissue apoptosis or necrosis. The aim of the present study is to assess the role of P2X₇ receptor in the kidneys of diabetic rats submitted to aerobic training or N-acetylcysteine supplementation. Diabetes was induced in male Wistar rats by streptozotocin (60 mg/kg, i.v.) and the training was done on a treadmill; N-acetylcysteine was given in the drinking water (600 mg/L). By confocal microscopy, as compared to control, the kidneys of diabetic rats showed increased P2×7 receptor expression and a higher activation in response to 2′(3′)-O-(4-benzoylbenzoyl) adenosine5'–triphosphate (specific agonist) and adenosine triphosphate (nonspecific agonist) (all p<0.05). All these alterations were reduced in diabetic rats treated with N-acetylcysteine, exercise or both. We also observed measured proteinuria and albuminuria (early marker of diabetic nephropathy) in DM groups. Lipoperoxidation was strongly correlated with P2X₇ receptor expression, which was also correlated to NO^•, thus associating this receptor to oxidative stress and kidney lesion. We suggest that P2X₇ receptor inhibition associated with the maintenance of redox homeostasis could be useful as coadjuvant treatment to delay the progression of diabetic nephropathy.