The role of oxygen free radicals in cisplatin-induced acute renal failure in rats

NADPH Oxidase 3: Beyond the Inner Ear

Reactive oxygen species (ROS) were formerly known as mere byproducts of metabolism with damaging effects on cellular structures. The discovery and description of NADPH oxidases (Nox) as a whole enzyme family that only produce this harmful group of molecules was surprising. After intensive research, seven Nox isoforms were discovered, described and extensively studied. Among them, the NADPH oxidase 3 is the perhaps most underrated Nox isoform, since it was firstly discovered in the inner ear. This stigma of Nox3 as "being only expressed in the inner ear" was also used by me several times. Therefore, the question arose whether this sentence is still valid or even usable. To this end, this review solely focuses on Nox3 and summarizes its discovery, the structural components, the activating and regulating factors, the expression in cells, tissues and organs, as well as the beneficial and detrimental effects of Nox3-mediated ROS production on body functions. Furthermore, the involvement of Nox3-derived ROS in diseases progression and, accordingly, as a potential target for disease treatment, will be discussed.

Targeting CXCL1 chemokine signaling for treating cisplatin ototoxicity

Cisplatin is chemotherapy used for solid tumor treatment like lung, bladder, head and neck, ovarian and testicular cancers. However, cisplatin-induced ototoxicity limits the utility of this agent in cancer patients, especially when dose escalations are needed. Ototoxicity is associated with cochlear cell death through DNA damage, the generation of reactive oxygen species (ROS) and the consequent activation of caspase, glutamate excitotoxicity, inflammation, apoptosis and/or necrosis. Previous studies have demonstrated a role of CXC chemokines in cisplatin ototoxicity. In this study, we investigated the role of CXCL1, a cytokine which increased in the serum and cochlea by 24 h following cisplatin administration. Adult male Wistar rats treated with cisplatin demonstrated significant hearing loss, assessed by auditory brainstem responses (ABRs), hair cell loss and loss of ribbon synapse. Immunohistochemical studies evaluated the levels of CXCL1 along with increased presence of CD68 and CD45-positive immune cells in cochlea. Increases in CXCL1 was time-dependent in the spiral ganglion neurons and organ of Corti and was associated with progressive increases in CD45, CD68 and IBA1-positive immune cells. Trans-tympanic administration of SB225002, a chemical inhibitor of CXCR2 (receptor target for CXCL1) reduced immune cell migration, protected against cisplatin-induced hearing loss and preserved hair cell integrity. We show that SB225002 reduced the expression of CXCL1, NOX3, iNOS, TNF-α, IL-6 and COX-2. Similarly, knockdown of CXCR2 by trans-tympanic administration of CXCR2 siRNA protected against hearing loss and loss of outer hair cells and reduced ribbon synapses. In addition, SB225002 reduced the expression of inflammatory mediators induced by cisplatin. These results implicate the CXCL1 chemokine as an early player in cisplatin ototoxicity, possibly by initiating the immune cascade, and indicate that CXCR2 is a relevant target for treating cisplatin ototoxicity.

Prophylactic Treatment with Hydrogen Sulphide Can Prevent Renal Ischemia-Reperfusion Injury in L-NAME Induced Hypertensive Rats with Cisplatin-Induced Acute Renal Failure

(Background and Objectives): Renal ischemia perfusion injury is one of the major issues in kidney transplant. The aim of the study was to investigate the hypothesis that prophylactic treatment-with a hydrogen sulphide donor to an acute renal failure case of hypertensive rats-can minimize the ischemia reperfusion injury of the kidney which is beneficial for kidney transplant. To check this hypothesis, the present study was designed to investigate the effect of chronic administration of a hydrogen sulphide (H2S) donor and sodium hydrosulfide (NaHS) on nuclear factor kappa B (NF-kB) and inter cellular adhesion molecule-1 (ICAM-1) concentration in non-renal failure (NRF) and acute renal failure (ARF) rats in the ischemia-reperfusion injury (IRI) model of the kidney in both normotensive WKY and hypertensive rats (L-nitro arginine methyl ester (L-NAME-induced); (Materials and Methods): A total number of 48 Sprague-Dawley rats were recruited into eight groups each consisting of six animals. Each of these eight groups was used to measure systemic and renal parameters, H2S, antioxidant parameters in plasma, plasma concentration of NF-kB and ICAM-1 and renal cortical blood pressure. ARF was induced by single intraperitoneal (i.p.) cisplatin injection (5 mg/kg). Hypertension was induced by oral administration of L-NAME in drinking water for four weeks at 40 mg/kg/day. NaHS was administered (i.p) at 56 µmol/kg for five weeks while dL-propargylglycine (PAG), a H2S generation inhibitor, was administered as a single intra-peritoneal injection (50 mg/kg). An acute surgical experiment was performed for the induction of renal ischemia for 30 min by renal artery clamping followed by reperfusion for three hours; (Results): Chronic administration of NaHS attenuated the severity of ARF in both normotensive and hypertensive animals (L-NAME) along with lowering the blood pressure in hypertensive groups. NaHS improved the oxidative stress parameters such as total superoxide dismutase (T-SOD), glutathione (GSH) and reduced the malondialdehyde (MDA) concentration along with reduction of NF-kB and ICAM-1 following renal IRI; Conclusions: These findings demonstrate that H2S not only reduced the severity of cisplatin induced ARF but also reduced the severity of renal IRI by upregulating antioxidants along with decreased concentrations of NF-kB and ICAM-1 in normotensive and L-NAME induced hypertensive rats.

Tissue Culture Models of AKI: From Tubule Cells to Human Kidney Organoids

AKI affects approximately 13.3 million people around the world each year, causing CKD and/or mortality. The mammalian kidney cannot generate new nephrons after postnatal renal damage and regenerative therapies for AKI are not available. Human kidney tissue culture systems can complement animal models of AKI and/or address some of their limitations. Donor-derived somatic cells, such as renal tubule epithelial cells or cell lines (RPTEC/hTERT, ciPTEC, HK-2, Nki-2, and CIHP-1), have been used for decades to permit drug toxicity screening and studies into potential AKI mechanisms. However, tubule cell lines do not fully recapitulate tubular epithelial cell properties in situ when grown under classic tissue culture conditions. Improving tissue culture models of AKI would increase our understanding of the mechanisms, leading to new therapeutics. Human pluripotent stem cells (hPSCs) can be differentiated into kidney organoids and various renal cell types. Injury to human kidney organoids results in renal cell-type crosstalk and upregulation of kidney injury biomarkers that are difficult to induce in primary tubule cell cultures. However, current protocols produce kidney organoids that are not mature and contain off-target cell types. Promising bioengineering techniques, such as bioprinting and "kidney-on-a-chip" methods, as applied to kidney nephrotoxicity modeling advantages and limitations are discussed. This review explores the mechanisms and detection of AKI in tissue culture, with an emphasis on bioengineered approaches such as human kidney organoid models.

The protective impacts of Spirulina platensis against cisplatin-induced renal injury through the regulation of oxidative stress, pro-inflammatory cytokines and Bax/Bcl2

One of the main antineoplastic chemotherapy medications is cisplatin, of which nephropathy is a major side effect. In this current study, we aim to investigate the molecular protective effect of Spirulina platensis (SP) on cisplatin-induced nephrotoxicity. In total, 48 healthy male albino rats were allocated into 4 groups. Group 1 received saline intraperitoneally (IP) twice per week (normal rats). Group 2 received SP (100 mg/kg BW orally). Group 3 were injected with cisplatin (1.5 mg/kg IP) twice per week. Group 4 received SP and on the 4th day received cisplatin (1.5 mg/kg IP) for 21 days. After 3 weeks of experiment, blood and renal tissues were taken for serum analysis, gene expression using qRT-polymerase chain reaction, and renal histopathology. As per our findings, it was found that SP significantly ameliorated the alterations in body weight, relative kidney weight, and the disturbance in examined renal markers. Furthermore, SP recovered and restored cisplatin-induced oxidative stress biomarkers (MDA and NO) and antioxidant activity (SOD and GSH) and cisplatin-induced upregulation in the gene expression of TNF-α, inducible nitric oxide synthase, TGF1-β, IL-1β, and IL-6. Interestingly, these gene expressions were ameliorated by the SP pre-administration. Furthermore, cisplatin upregulated pro-apoptotic gene Bax, whereas it downregulated anti-apoptotic gene Bcl2. Interestingly, SP mitigated this alteration in apoptosis and anti-apoptotic associated genes. Renal histopathology revealed the protective impacts of SP against cisplatin-induced severe glomerular congestion, hemorrhage, inflammatory cell infiltration, degeneration, and severe necrosis in renal glomeruli and tubules. In conclusion, SP has a protective effect against cisplatin-induced renal damage through modulating oxidative stress and anti-inflammatory, anti-necrotic, and anti-apoptotic-associated genes.

Novel pharmacological effects of lecithinized superoxide dismutase on ischemia/reperfusion injury in the kidneys of mice

Renal ischemia/reperfusion (I/R) injury is a major clinical problem because it can cause acute kidney injury (AKI) or lead to the transition from AKI to chronic kidney disease (CKD). Oxidative stress, which involves the production of reactive oxygen species (ROS), plays an important role in the development and exacerbation of I/R-induced kidney injury. However, we have previously reported that lecithinized superoxide dismutase (PC-SOD), a SOD derivative with high tissue affinity and high stability in plasma, has beneficial effects in various disease models because of its inhibitory effect on ROS production. Therefore, we aimed to determine the effects of intravenous PC-SOD administration in a mouse model of renal injury induced by I/R. PC-SOD markedly ameliorated the I/R-induced increases in markers of renal damage (urea nitrogen, creatinine, neutrophil gelatinase-associated lipocalin, and interleukin-6) and tubular necrosis 48 h after the intervention. We also found that PC-SOD significantly ameliorated the I/R-induced increase in ROS production, using an ex vivo imaging system. Furthermore, PC-SOD inhibited the increases in expression of markers of fibrosis (α-smooth muscle actin and collagen 1A1) 96 h after, and renal fibrosis 25 days after I/R was induced. Finally, we found that PC-SOD ameliorated the I/R-induced AKI in mice with high-fat diet-induced prediabetes. These results suggest that PC-SOD inhibits AKI and the transition from AKI to CKD through the inhibition of ROS production. Therefore, we believe that PC-SOD may represent an effective therapeutic agent for I/R-induced renal injury.

Nephroprotective effect of Apium graveolens L. against Cisplatin-induced nephrotoxicity

Background

Cisplatin is extensively used in treating cancers, and its primary side-effect is nephrotoxicity. It accumulates in proximal convoluted tubules where it promotes cellular damage by oxidative stress, apoptosis, and inflammation, etc. In Unani medicine, Tukhm-e-Karafs(Apium graveolens L.) (TK) is mentioned in the literature to manage various kidney ailments due to its diuretic and deobstruent activities.

Objective

To investigate the nephroprotective effects of powder of TK in Cisplatin-induced nephrotoxicity in an animal model and to validate the Unani claim of its nephroprotective action.

Material and methods

In curative protocol, cisplatin (5 mg/kg body weight i.p) was administered on day one and powder of TK (500 and 1000 mg/kg p.o.) from the sixth day onwards for ten days. TK (500 and 1000 mg/kg p.o.) was given for ten days and Cisplatin (5 mg/kg body weight i.p) on day 11 in the protective model. At the end of the study, all the animals were sacrificed, and renal biochemical parameters were determined. KIM-1 level was also investigated in the kidney homogenate in conjunction with histopathological inspection of kidney tissues.

Results

Significant increase in serum creatinine and BUN, presence of mononuclear cell infiltration, tubular dilation and vacuolation in renal histopathology, and increased KIM-1 level confirmed the nephrotoxicity due to Cisplatin. TK's administration protects the kidney as suggested by the changes in biochemical renal function, decreased level of KIM-1, and improvement in histopathological changes.

Conclusion

The result advocated that TK prevented renal injury and maintained normal renal function in both models. It may be due to improved clearance of Cisplatin from kidney tubules and reduction in reactive oxygen species (ROS) produced by the inflammatory response.

Progress in protecting vestibular hair cells

Vestibular hair cells are mechanosensory receptors that are capable of detecting changes in head position and thereby allow animals to maintain their posture and coordinate their movement. Vestibular hair cells are susceptible to ototoxic drugs, aging, and genetic factors that can lead to permanent vestibular dysfunction. Vestibular dysfunction mainly results from the injury of hair cells, which are located in the vestibular sensory epithelium. This review summarizes the mechanisms of different factors causing vestibular hair cell damage and therapeutic strategies to protect vestibular hair cells.

Effects of HIF-1α on renal fibrosis in cisplatin-induced chronic kidney disease

Cisplatin (Cis) can cause chronic kidney disease (CKD) and promote renal fibrosis, but the underlying mechanism is not fully understood. Hypoxia inducible factor-1α (HIF-1α) can promote renal fibrosis in some kidney diseases, but its role in Cis-induced CKD is still unknown. Notch-1 is a recognized molecule that promotes renal fibrosis under pathological circumstances, and evidence shows that HIF-1α and Notch-1 are closely related to each other. In the present study, mice with HIF-1α gene knockout in proximal tubular cells (PTCs) (PT-HIF-1α-KO) were generated and treated with Cis to induce CKD. A human proximal tubular cell line (HK-2) and primary mouse PTCs were used for in vitro studies. The results showed that HIF-1α was increased in the kidneys of Cis-treated wild-type mice, accompanied by elevated Notch-1, Notch-1 intracellular domain (N1ICD), Hes-1 and renal fibrosis. However, these alterations were partially reversed in PT-HIF-1α-KO mice. Similar results were observed in HK-2 cells and primary mouse PTCs. In addition, treating the cells with Cis induced a marked interaction of HIF-1α and N1ICD. Further inhibiting Notch-1 significantly reduced cellular fibrogenesis but did not affect HIF-1α expression. The data suggested that HIF-1α could promote renal fibrosis in Cis-induced CKD by activating Notch-1 both transcriptionally and post-transcriptionally and that HIF-1α may serve as a potential therapeutic target for Cis-induced CKD.

Ergothioneine mitigates cisplatin-evoked nephrotoxicity via targeting Nrf2, NF-κB, and apoptotic signaling and inhibiting γ-glutamyl transpeptidase

AIM

Cisplatin is a potent chemotherapeutic agent whose therapeutic application is hindered by the associated nephrotoxicity. Cisplatin-evoked nephrotoxicity has been largely attributed to the induction of oxidative stress and inflammatory responses. The current study aimed at investigating the ability of ergothioneine to mitigate cisplatin-evoked nephrotoxicity and to elucidate the underlining molecular mechanisms.

MAIN METHODS

Wistar rats were treated with a daily dose of ergothioneine (70 mg/kg, po) for fourteen days and a single dose of cisplatin (5 mg/kg, ip) on day ten. On day fifteen, kidneys and blood specimens were collected and subjected to Western blotting, ELISA, histopathological, and spectrophotometric analysis.

KEY FINDINGS

Ergothioneine significantly enhanced renal function in cisplatin-treated rats as manifested by increased GFR and decreased serum creatinine and blood urea nitrogen. Ergothioneine effectively reduced the cisplatin-induced oxidative stress and mitigated apoptosis and the histopathological changes. Mechanistically, ergothioneine induced the expression of the antioxidant transcription factor Nrf2 and up-regulated its downstream targets NQO1 and HO-1. Equally important, ergothioneine inhibited γ-glutamyl transpeptidase that plays crucial roles in biotransformation of cisplatin into a toxic metabolite. Additionally, it reduced the pro-apoptotic protein p53 and the inflammatory transcription factor NF-κB along with its downstream pro-inflammatory cytokines TNF-α and IL-1β.

SIGNIFICANCE

The results of the current work shed the light on the ameliorating effect of ergothioneine on cisplatin-evoked nephrotoxicity that is potentially mediated through modulation of Nrf2, p53, and NF-κB signaling and inhibition of γ-glutamyl transpeptidase. This findings support the potential application of ergothioneine in controlling cisplatin-associated nephrotoxicity although clinical investigations are warranted.

Advances in Our Understanding of the Molecular Mechanisms of Action of Cisplatin in Cancer Therapy

Cisplatin and other platinum-based chemotherapeutic drugs have been used extensively for the treatment of human cancers such as bladder, blood, breast, cervical, esophageal, head and neck, lung, ovarian, testicular cancers, and sarcoma. Cisplatin is commonly administered intravenously as a first-line chemotherapy for patients suffering from various malignancies. Upon absorption into the cancer cell, cisplatin interacts with cellular macromolecules and exerts its cytotoxic effects through a series of biochemical mechanisms by binding to Deoxyribonucleic acid (DNA) and forming intra-strand DNA adducts leading to the inhibition of DNA synthesis and cell growth. Its primary molecular mechanism of action has been associated with the induction of both intrinsic and extrinsic pathways of apoptosis resulting from the production of reactive oxygen species through lipid peroxidation, activation of various signal transduction pathways, induction of p53 signaling and cell cycle arrest, upregulation of pro-apoptotic genes/proteins, and down-regulation of proto-oncogenes and anti-apoptotic genes/proteins. Despite great clinical outcomes, many studies have reported substantial side effects associated with cisplatin monotherapy, while others have shown substantial drug resistance in some cancer patients. Hence, new formulations and several combinational therapies with other drugs have been tested for the purpose of improving the clinical utility of cisplatin. Therefore, this review provides a comprehensive understanding of its molecular mechanisms of action in cancer therapy and discusses the therapeutic approaches to overcome cisplatin resistance and side effects.

Is the Way to Fight Cancer Paved with Gold? Metal-Based Carbene Complexes with Multiple and Fascinating Biological Features

Herein, we report the synthesis and the multiple anti-tumor properties of new gold and silver carbene complexes. The chemical modifications, grounded on our previous studies, led us to identify a good lead complex, gold-based, whose biological features are very exciting and promising in the anti-cancer research and could be further developed. Indeed, the bis-[4,5-dichloro-(N-methyl-N’(2-hydroxy-2-phenyl)ethyl-imidazole-2-ylidene)gold(I)]⁺[dichloro-gold]⁻ (AuL7) complex possesses the ability to interfere with at least three important and different intracellular targets, namely the human topoisomerases I and II and tubulin, which are able to modulate metabolic processes not directly correlated each other. We proved that the modifications of the ligands structure in AuL7, with respect to another already published complex, i.e., bis-[4,5-dichloro-(N-methyl-N’(cyclopentane-2ol)-imidazole-2-ylidine)gold(I)]⁺[dichloro-gold]⁻ (AuL4), produce a different behavior toward tubulin-polymerization process, since AuL7 is a tubulin-polymerization inhibitor and AuL4 a stabilizer, with the final same result of hampering the tumor growth. Taken together, our outcomes designate AuL7 as a promising compound for the development of multi-targeted anti-cancer therapies.

Impact of garlic (Allium sativum) oil on cisplatin-induced hepatorenal biochemical and histopathological alterations in rats

Cisplatin (cis-diamminedichloridoplatinum II [CDDP]) is a chemotherapeutic agent used for treating different cancers types. However, its usage is limited because it induces harmful toxicities in multiple organs, including nephrotoxicity and hepatotoxicity. Garlic oil (GO) has several pharmacological activities, including antioxidant activity. The aim of the study is to evaluate the protective and antioxidant effects of GO against CDDP-induced acute liver and kidney injuries in male rats. CDDP-treated rats showed increased serum ALT, AST, ALP, LDH, uric acid, urea, creatinine, and IL-6 levels. Moreover, CDDP-treated rats showed significantly increased MDA and NO levels and decreased GSH level and T.SOD and CAT activities in hepatic and renal tissues compared with control rats. GO administration, especially at a dose of 100 ml/kg, alleviated CDDP-induced adverse biochemical and histopathological alterations and restored them to their normal values. These results suggest that GO reverses CDDP-induced hepatorenal damage by exerting antioxidant and anti-inflammatory effects.

Renal Sympathetic Nerve-Derived Signaling in Acute and Chronic kidney Diseases

The kidney is innervated by afferent sensory and efferent sympathetic nerve fibers. Norepinephrine (NE) is the primary neurotransmitter for post-ganglionic sympathetic adrenergic nerves, and its signaling, regulated through adrenergic receptors (AR), modulates renal function and pathophysiology under disease conditions. Renal sympathetic overactivity and increased NE level are commonly seen in chronic kidney disease (CKD) and are critical factors in the progression of renal disease. Blockade of sympathetic nerve-derived signaling by renal denervation or AR blockade in clinical and experimental studies demonstrates that renal nerves and its downstream signaling contribute to progression of acute kidney injury (AKI) to CKD and fibrogenesis. This review summarizes our current knowledge of the role of renal sympathetic nerve and adrenergic receptors in AKI, AKI to CKD transition and CKDand provides new insights into the therapeutic potential of intervening in its signaling pathways.

Antioxidant and anti-apoptotic effects of vitexilactone on cisplatin-induced nephrotoxicity in rats

Cisplatin (CP) is an antineoplastic drug; however, owing to its nephrotoxicity, its clinical use is limited. We investigated whether vitexilactone (vitex) is a safe and effective treatment for CP induced kidney injury. We allocated Sprague-Dawley rats into six groups: control group, low dose-high dose vitex groups (40 and 80 mg/kg vitex for 6 days before administration of CP), CP group (single 6 mg/kg dose on day 6) and CP + low dose vitex-CP + high dose vitex group (40 and 80 mg/kg vitex for 6 days, and a single 6 mg/kg dose of CP on day 6. Rats were euthanized 5 days after CP treatment. After exposure to CP and/or vitex, total oxidative stress and total antioxidant status were assessed. The histology of the kidney was examined using hematoxylin and eosin, and periodic acid-Schiff. We used immunohistochemical and fluorescence staining to detect expression of caspase-3. We also measured blood urea nitrogen, uric acid and creatinine levels. Nephroprotective effects of vitex were associated with decreased serum toxicity markers and increased antioxidant activity. Vitex also reduced the expression of the apoptosis marker, caspase-3. Treatment with CP increased blood urea nitrogen, uric acid, creatinine levels and total antioxidant status, and decreased total antioxidant status compared to the control group. Use of vitex for protection from CP induced nephrotoxicity appears to be a safe and efficacious alternative for treatment of kidney injury.

The effect of N-acetylcysteine on inflammation and oxidative stress in cisplatin-induced nephrotoxicity: a rat model

Background/Aim

Cisplatin is a highly effective chemotherapeutic agent used in the treatment of solid organ cancers. Besides its chemotherapeutic effectiveness, cisplatin administration is associated with numerous side effects. Of those, the most clinically significant and common effect is nephrotoxicity. Recent studies reported that oxidative stress and inflammation are probably the most important mechanisms that contribute to the nephrotoxicity. N-acetylcysteine (NAC) is an antioxidant and antiinflammatory agent. In the present study, the effects of NAC on cisplatin-induced nephrotoxicity were investigated.

Materials and methods

Rats were divided into four groups each including eight rats: CONT, NAC-250, CP, and CP+NAC. Rats in experimental groups were treated intraperitoneally (i.p.) with a single dose of cisplatin (10 mg/kg body weight) and i.p. with NAC (250 mg/kg body weight) for three consecutive days. Nephrotoxicity was determined by plasma BUN and creatinine levels. In tissue samples, myeloperoxidase (MPO), nuclear factor-kappa B (NF-kB), high mobility group box-1 (HMGB-1), total oxidant status (TOS), and total antioxidant status (TAS) levels were measured. Kidneys were analyzed histopathologically as well.

Results

It was revealed that cisplatin was not effective on MPO, HMGB-1 and NF-kB levels but did increase TOS levels and decrease TAS levels in tissue samples. Interestingly, NAC elevated MPO and HMGB-1 levels significantly. Nevertheless, NAC ameliorated histological and functional changes in kidney tissues.

Conclusion

It is suggested that inflammation has a limited effect on cisplatin nephrotoxicity in this experimental design, and, as reflected by decreased BUN and creatinine levels, NAC can be used as an additional therapeutic agent in standard cisplatin treatment protocols.

Evaluation of the Protective Effect of Cystone Against Cisplatin-induced Nephrotoxicity in Patients with Cancer: A Pilot Study

Introduction

Cisplatin is a widely used anti-cancer drug that is commonly administered for the treatment of various cancers. However, nephrotoxicity is the most important side effect of this drug which limits its use. This study aimed to investigate the protective effect of Cystone against nephrotoxicity induced by Cisplatin in patients with cancer.

Methods

This pilot clinical trial study was conducted on 43 cancer patients treated with Cisplatin (75 mg/m2 for a period of six months). The subjects were divided into treatment group (receiving Cystone, two per 8 hours; n = 21) and control group (n = 22). The two groups were compared with each other in terms of demographic and laboratory variables.

Results

In the intervention group receiving Cystone, serum creatinine-based GFR level (P = 0.453) and 24-hour urine creatinine-based GFR level (P = 0.397) did not change significantly during the studied period, but in the control group, serum creatinine-based GFR level (P = 0.013) and 24-hour urine creatinine-based GFR level (P = 0.016) significantly changed. Serum creatinine-based GFR level increased by 2.3 units in the intervention group and 10.5 units in the control group (P = 0.005) in the six months of the study. At the end of the sixth month, 24-hour urine creatinine-based GFR level increased by 2.2 units in the intervention group and 0.8 unit in the control group (P = 0.008).

Conclusions

The use of Cystone resulted in more stable kidney function indices in the intervention group, as compared with the control group. Therefore, Cystone seems to have a protective effect against nephrotoxicity induced by Cisplatin in cancer patients.

Curcumin Acts as a Chemosensitizer for Leiomyosarcoma Cells In Vitro But Fails to Mediate Antioxidant Enzyme Activity in Cisplatin-Induced Experimental Nephrotoxicity in Rats

Background. Cisplatin (cis-diamminedichloroplatinum) is a widely used chemotherapeutic agent for the treatment of various cancers. Although it represents an effective regimen, its application is accompanied by side effects to normal tissues, especially to the kidneys. Cisplatin generates free radicals and impairs the function of antioxidant enzymes. Modulation of cisplatin-induced oxidative stress by specific antioxidant molecules represents an attractive approach to minimize side effects. Methods. We studied the ability of curcumin to sensitize leiomyosarcoma (LMS) cells to cisplatin. Assays for cell proliferation, mitochondrial function, induction of apoptosis, and cell cycle arrest were performed using various concentrations of cisplatin and a concentration of curcumin that caused a nonsignificant reduction in cell viability. Moreover, the effect of curcumin was examined against cisplatin-induced experimental nephrotoxicity. Renal injury was assessed by measuring serum creatinine, blood urea nitrogen (BUN), and the kidney's relative weight. Oxidative stress was measured by means of enzymatic activities of superoxide dismutase and glutathione peroxidase in the rats' blood and malondialdehyde levels in rats' urine. Results. In our study, we found that curcumin sensitizes LMS cells to cisplatin by enhancing apoptosis and impairing mitochondrial function. In an in vivo model of cisplatin-induced experimental nephrotoxicity, intraperitoneal administration of curcumin failed to preserve blood's antioxidant enzyme activity and decrease lipid peroxidation. Nevertheless, curcumin was able to protect nephrons' histology from cisplatin's toxic effect. Conclusion. Our results showed that curcumin can act as chemosensitizer, but its role as an adjunctive cisplatin-induced oxidative stress inhibitor requires further dose-finding studies to maximize the effectiveness of chemotherapy.

Wogonin pre-treatment attenuates cisplatin-induced nephrotoxicity in rats: Impact on PPAR-γ, inflammation, apoptosis and Wnt/β-catenin pathway

Cisplatin, a platinum chemotherapeutic agent, is used in a diversity of malignancies; nevertheless, the excessive nephrotoxicity following cisplatin treatment is the dose-limiting devastating reaction. This study was designed to explore the possible nephroprotective impact of wogonin, a forceful anti-oxidant, anti-inflammatory, and anti-tumor agent, in a rat model of cisplatin-induced renal injury. The potential nephroprotective mechanisms were additionally investigated. Wogonin was given at a dose of 40 mg/kg. Acute nephrotoxicity was indicated by a significant rise in BUN, and serum creatinine levels in cisplatin-injected rats. Also, cisplatin enhanced the lipid peroxidation, diminished GSH, catalase, and PPAR-γ levels. Additionally, cisplatin-injected rats showed a significant rise in tissue levels of IL-1β, TNF-α, NF-kB, and caspase-3 enzymatic activity. Notably, the pre-treatment with wogonin ameliorated the nephrotoxicity indices, oxidative stress, inflammation, and apoptosis induced by cisplatin. Also, wogonin up-regulated PPAR-γ expression. The involvement of Wnt/β-catenin pathway was debatable; however, our findings showed that it was significantly induced by cisplatin. Wogonin pre-treatment markedly attenuated Wnt/β-catenin pathway. Collectively, these findings imply that wogonin is a promising nephroprotective agent that improves the therapeutic index of cisplatin via reducing oxidative stress, inflammation as well as inducing PPAR-γ. Also, Wnt/β-catenin pathway is partially involved in the pathogenesis of cisplatin nephrotoxicity.

Prophylactic effect of ethyl pyruvate on renal ischemia/reperfusion injury mediated through oxidative stress

PURPOSE

As oxidative stress (OXS) has been shown to play a primary role in renal ischemia/reperfusion injury (RIRI), we investigated whether antioxidant such as ethyl pyruvate (EPy) might effectively prevent RIRI. Possible prophylactic effects of EPy and mannitol (Mann), one of perioperative agents often used, were tested against harmful OXS in vitro.

METHODS

Hydrogen peroxide (H₂O₂) was used to exert OXS on the renal proximal tubular MDCK cells. Severity of OXS and protective effects of EPy and Mann were assessed by lipid peroxidation assay and cell viability test, respectively. The cytotoxic mechanism of H₂O₂ was explored by examining the status of glycolysis, metabolic signaling pathways, cell cycle, and induction of apoptosis.

RESULTS

Although H₂O₂ (500 µM) increased OXS by ~ 3.5 times of controls, EPy (1 mM) fully reduced it to the basal level. Cell viability declined to merely 10% by H₂O₂ was regained to > 90% with EPy. Hexokinase activity and ATP level also declined significantly by H₂O₂, but they sustained 80-90% with EPy. Additionally, H₂O₂ led to the modulations of metabolic signaling regulators, a G₁ cell cycle arrest, and induction of apoptosis, which were yet prevented with EPy. Unlike EPy, Mann had virtually little effects.

CONCLUSIONS

OXS can indeed lead to the significant cell viability reduction through its adverse cellular effects, ultimately resulting in RIRI. However, EPy appears to prevent these effects and protect MDCK cells, while Mann does not. Thus, EPy could be a more effective prophylactic renoprotective agent (than Mann) against oxidative renal cell injury including RIRI.

Suppressive Effects of EGCG on Cervical Cancer

Cervical cancer is the fourth most common gynecological cancer worldwide. Although prophylactic vaccination presents the most effective method for cervical cancer prevention, chemotherapy is still the primary invasive intervention. It is urgent to exploit low-toxic natural anticancer drugs on account of high cytotoxicity and side-effects of conventional agents. As a natural product, (-)-epigallocatechingallate (EGCG) has abilities in anti-proliferation, anti-metastasis and pro-apoptosis of cervical cancer cells. Moreover, EGCG also has pharmaceutical synergistic effects with conventional agents such as cisplatin (CDDP) and bleomycin (BLM). The underlying mechanisms of EGCG suppressive effects on cervical cancer are reviewed in this article. Further research directions and ambiguous results are also discussed.

Oral deferiprone administration ameliorates cisplatin-induced nephrotoxicity in rats

OBJECTIVES

Cisplatin is one of the widely used antitumour agents with major clinical side effect, nephrotoxicity. We showed the role of iron in cisplatin-induced nephrotoxicity that entrance to the cell via transferrin receptor (TfR) as a gatekeeper for iron uptake. We also examined the effect of iron chelator deferiprone against this toxicity.

METHODS

Thirty male Wistar rats were randomly divided into six groups. Group I (saline orally for 10 days); group II (saline orally for 10 days plus single injection of cisplatin 7 mg/kg, intraperitoneally on 5^th day); groups III, IV and V (deferiprone 50, 100 and 200 mg/kg orally for 10 days, respectively, plus cisplatin on 5th day). Group VI (deferiprone, orally).

RESULTS

Deferiprone provided functional and significant histological-proven protection in group IV. Deferiprone attenuated the increased creatinine, BUN, malondialdehyde and iron concentrations in cisplatin-injected animals. The increased amounts of TfR and decreased levels of HIF-1α and related anti-apoptotic genes expression in cisplatin-treated animals were improved by deferiprone.

CONCLUSIONS

The results supported a role for iron in cisplatin-induced nephrotoxicity and TfR may serve as an important source of iron. Based on these findings, deferiprone pretreatment may play a role in preventing cisplatin-induced nephropathy in cancer patient.

D-pinitol attenuates cisplatin-induced nephrotoxicity in rats: Impact on pro-inflammatory cytokines

Cisplatin has been widely used as a first-line agent against various forms of solid cancers. However, nephrotoxicity is the major limiting factor for its clinical use. Several clinical and pre-clinical studies have suggested different strategies for the reduction of cisplatin-induced nephrotoxicity. The present study was conducted to investigate the efficacy of D-Pinitol, against cisplatin-induced nephrotoxicity in Swiss albino mice. A single intraperitoneal injection of cisplatin (20 mg/kg) was used to induce nephrotoxicity in mice. Administration of cisplatin in mice is linked with elevated oxidative stress, imbalanced biochemical parameters, apoptosis and stimulation of mitogen-activated protein kinase (MAPK) pathway. D-Pinitol is a member of the flavonoid family and a chief constituent of Sutherlandia fruitesecnce. It was administered with saline water (10, 20, 40 mg/kg, p.o.) for seven consecutive days after a single dose of cisplatin. At the end of experiment, animals were sacrificed and biochemical parameters in serum and urine were recorded. Kidneys were isolated for the estimation of tumor necrosis factor-alpha, interleukin-1β, interlukin-6 levels and histopathological evaluations. It was noted that D-Pinitol significantly ameliorated biochemical levels of serum and urinary creatinine and blood urea nitrogen. Tissue homogenate levels of TNF-α, IL-6, IL-1β and the renal expression of tissue nitrites were also significantly decreased in D-Pinitol treated mice. These results were supplemented by histopathological findings. This study highlights the potential role of D-Pinitol against cisplatin-induced toxicity, exhibited through favorable alterations in biochemical and histological changes as well as reduction in oxidative stress and cytokine levels.

Combined but not single administration of vitamin C and l-carnitine ameliorates cisplatin-induced gastric mucosa damage in male rats

Although cisplatin is a potent anticancer drug, it instigates oxidative and pro-inflammatory reactions that pose significant and distressing clinical symptoms. Therefore, this study investigated the effects of vitamin C and (or) l-carnitine on cisplatin-induced gastric mucosa damage in rat. The rats were allocated into 6 groups (n = 5). The control group received distilled water, while the treatment groups received cisplatin alone (CIP), or cisplatin with vitamin C, l-carnitine, or their combination. Cisplatin caused disruption of the gastric mucosa histoarchitecture and altered the mucus barrier function. Moreover, the stomach tissue of the CIP-treated group showed increased levels of oxidative stress markers (malondialdehyde and H₂O₂) and decreased activities of antioxidant (superoxide dismutase, glutathione peroxidase, catalase, glutathione S-transferase) and non-antioxidant (reduced glutathione) enzymes. These deleterious events were accompanied with significant increases in pro-inflammatory cytokines and inflammatory infiltration markers, myeloperoxidase and inducible nitric oxide synthase. However, the administration of both vitamin C and l-carnitine, and not either of the two showed additive effects in attenuating the adverse effects of cisplatin. The histological results agreed with the biochemical assays. The study concluded that the combined administration of vitamin C and l-carnitine, but not the single therapy, could prevent the adverse effects of cisplatin on gastric tissue.

Nitrolipids in kidney physiology and disease

The kidneys are vital organs responsible for maintaining body fluid homeostasis within proper physiologic ranges. Kidney disease is an epidemic clinical problem causing significant morbidity and mortality, and current treatments are limited to renin-angiotensin system blockade or renal replacement therapy for the majority of affected individuals. There is a critical, unmet need for novel pharmacological agents to improve the outcome of patients with kidney disease. Nitro-oleic acid (NO2-OA) is an endogenously generated electrophilic compound with the capacity to modify thiols in proteins, altering their function. The most important targets appear to be the Keap1/Nrf2 and NF-κB pathways, which have widespread effects on antioxidant, detoxifying, and inflammatory responses in cells and tissues. Through these and potentially additional protective actions, NO2-OA may be capable of preserving or enhancing kidney function in acute and chronic kidney diseases.

Pyridylphosphinate metal complexes: synthesis, structural characterisation and biological activity

For the first time, a series of 25 pseudo-octahedral pyridylphosphinate metal complexes (Ru, Os, Rh, Ir) has been synthesised and assessed in biological systems. Each metal complex incorporates a pyridylphosphinate ligand, a monodentate halide and a capping η(6)-bound aromatic ligand. Solid- and solution-state analyses of two complexes reveal a structural preference for one of a possible two diastereomers. The metal chlorides hydrolyse rapidly in D2O to form a 1 : 1 equilibrium ratio between the aqua and chloride adducts. The pKa of the aqua adduct depends upon the pyridyl substituent and the metal but has little dependence upon the phosphinate R' group. Toxicity was measured in vitro against non-small cell lung carcinoma H460 cells, with the most potent complexes reporting IC50 values around 50 μM. Binding studies with selected amino acids and nucleobases provide a rationale for the variation in toxicity observed within the series. Finally, an investigation into the ability of the chelating amino acid l-His to displace the phosphinate O-metal bond shows the potential for phosphinate complexes to act as prodrugs that can be activated in the intracellular environment.

Citrullus colocynthis Linn. Fruit extract ameliorates cisplatin-induced hepato-renal toxicity in rats

Background Cisplatin-induced acute liver and kidney injuries are serious problems in cancer patients during treatment of solid tumours. Objective This study sought to investigate possible protective effect of ethanolic fruit extract of Citrullus colocynthis (CC) against cisplatin-induced hepato-renal toxicity in rats. Methods Thirty male albino rats (150-200 g) were divided into five groups (n=6) and treated as follows: group 1: vehicle (10 mL/kg, p.o.; normal control); group 2: vehicle (10 mL/kg); groups 3-5: CC (100, 200 or 400 mg/kg, p.o.), respectively, for 10 days. Cisplatin (7.5 mg/kg; i.p.) was administered on the 7th day to animals in groups (2-5) 1 h after pretreatment. The animals were euthanized on day 10 for haematological, biochemical and histological analysis. Results Cisplatin induced a significant increase in the serum levels of ALT, ALP, creatinine and blood urea nitrogen indicative of hepato-renal injury. More so, cisplatin caused marked increase in granulocyte, lymphocyte and platelets counts which were ameliorated by CC (100-400 mg/kg) treatment. In addition, cisplatin induced marked increase in MDA and nitrite levels coupled with deficits in glutathione, catalase and superoxide dismutase activities which were attenuated by CC administration. In vitro assay showed that CC scavenged DPPH and nitrite radicals (69.50 and 64.50 µg/mL, respectively). Total antioxidant capacity, phenolic and flavonoid contents are 24.27±0.09 mg QUE/g, 17.14±0.12 mg GAE/g and 10.20±0.09 mg QUE/g, respectively. CC preserved the liver and kidney histoarchitecture. Conclusions This study showed that C. colocynthis possesses hepatoprotective and nephroprotective actions possibly through enhancement of antioxidant defence system. Thus, it could be a potential adjuvant in cisplatin-based chemotherapy.

Cytoprotective Effects of Cell-Permeable Bifunctional Antioxidant Enzyme, GST-TAT-SOD, against Cisplatin-Induced Cell Damage

GST-TAT-SOD, a cell-permeable bifunctional antioxidant enzyme, is a potential selective radioprotector. This study aimed to investigate the cytoprotective activity of GST-TAT-SOD against cisplatin-induced damage. The current study showed that cisplatin induced the formation of reactive oxygen species in normal L-02 cells. GST-TAT-SOD (2000 U/mL) executed its antioxidant role by directly scavenging excess intracellular free radicals and augmenting cellular antioxidant defense such as reducing MDA level, enhancing the SOD activity, GST activity, and T-AOC. Thus, it suppressed the growth inhibition and apoptosis of cisplatin-treated normal cells. Meanwhile, the growth inhibition of tumor cells (SMMC-7721) caused by cisplatin was unaffected by GST-TAT-SOD pretreatment. GST-SOD, as a comparison, seemed to be powerless for related indicators as it could not enter into cells without cell-permeating peptide. These results suggest that GST-TAT-SOD might be a potential cytoprotective agent for cisplatin-induced side effects.

Targeting autophagy to modulate cell survival: a comparative analysis in cancer, normal and embryonic cells

Autophagy is linked to multiple cancer-related signaling pathways, and represents a defense mechanism for cancer cells under therapeutic stress. The crosstalk between apoptosis and autophagy is essential for both tumorigenesis and embryonic development. We studied the influence of autophagy on cell survival in pro-apoptotic conditions induced by anticancer drugs in three model systems: human cancer cells (NCI-H460, COR-L23 and U87), human normal cells (HaCaT and MRC-5) and zebrafish embryos (Danio rerio). Autophagy induction with AZD2014 and tamoxifen antagonized the pro-apoptotic effect of chemotherapeutics doxorubicin and cisplatin in cell lines, while autophagy inhibition by wortmannin and chloroquine synergized the action of both anticancer agents. This effect was further verified by assessing cleaved caspase-3 and PARP-1 levels. Autophagy inhibitors significantly increased both apoptotic markers when applied in combination with doxorubicin while autophagy inducers had the opposite effect. In a similar manner, autophagy induction in zebrafish embryos prevented cisplatin-induced apoptosis in the tail region while autophagy inhibition increased cell death in the tail and retina of cisplatin-treated animals. Autophagy modulation with direct inhibitors of the PI3kinase/Akt/mTOR pathway (AZD2014 and wortmannin) triggered the cellular response to anticancer drugs more effectively in NCI-H460 and zebrafish embryonic models compared to HaCaT suggesting that these modulators are selective towards rapidly proliferating cells. Therefore, evaluating the autophagic properties of chemotherapeutics could help determine more accurately the fate of different cell types under treatment. Our study underlines the importance of testing autophagic activity of potential anticancer agents in a comparative approach to develop more rational anticancer therapeutic strategies.

The effects of 2,3-dimercapto-1-propanesulfonic acid (DMPS) and meso-2,3-dimercaptosuccinic acid (DMSA) on the nephrotoxicity in the mouse during repeated cisplatin (CDDP) treatments

Previously, we reported that specific lower dose of sodium 2,3-dimercapto-1-propanesulfonic acid (DMPS) which is an antidote to heavy metal intoxication, inversely enhanced cisplatin (CDDP)-induced antitumor activity to S-180 cell-bearing mouse. This activity was only weak with meso-2,3-dimercaptosuccinic acid (DMSA), however. This study investigated the effects of lower doses of DMPS or DMSA on the nephrotoxicity and kinetics of CDDP. Kidney and blood isolated from female mice which received CDDP with or without DMPS or DMSA once daily for 4 days were provided for measuring levels of blood urea nitrogen (BUN) and transporter proteins (OCT2: organic cation transporter; MATE1: multidrug and toxin extrusion) mRNA, and CDDP-originated platinum, and TUNEL staining of renal tubular cells. DMPS or DMSA reduced effectively CDDP-induced BUN, and caused a moderate reduction of platinum in kidney. Additionally, both dimercapto-compounds restored the CDDP-reduced mRNA levels of transporter proteins (OCT2 and MATE1), and apparently suppressed the CDDP-induced apoptosis. These results suggest that DMPS, as well as DMSA, at approximate 17-fold dose (μmol/kg) of CDDP, has an enough potential to reverse the CDDP nephrotoxicity, and concomitant use of DMPS considering both dose and timing for administration is potentially useful for preventing nephrotoxicity and enhancing antitumor activity during CDDP chemotherapy.

Cisplatin-Induced Nephrotoxicity; Protective Supplements and Gender Differences

Cisplatin (CDDP) has been widely used as a chemotherapeutic agent for solid tumors. The most common side effect of CDDP is nephrotoxicity, and many efforts have been made in the laboratory and the clinic to employ candidate adjuvants to CDDP to minimize this adverse influence. Many synthetic and herbal antioxidants as well as trace elements have been investigated for this purpose in recent years and a variety of positive and negative results have been yielded. However, no definitive supplement has so far been proposed to prevent CDDP-induced nephrotoxicity; however, this condition is gender related and the sex hormone estrogen may protect the kidney against CDDP damage. In this review, the results of research related to the effect of different synthetic and herbal antioxidants supplements are presented and discussed with suggestions included for future work.

Protective Effect of Withania coagulans Fruit Extract on Cisplatin-induced Nephrotoxicity in Rats

Background:

Fruits of Withania coagulans (Solanaceae) reported to possess several bioactive compounds as curative agents for various clinical conditions. Cisplatin is a chemotherapeutic drug to treat sarcomas, carcinomas, lymphomas, cervical cancer, germ cell tumors, etc. The major factor that limits its clinical use is its dose-dependent nephrotoxicity.

Aim:

To explore the nephroprotective effect of W. coagulans extract and its modulatory effects against cisplatin-induced nephrotoxicity and genotoxicity.

Materials and Methods:

W. coagulans fruit extract was quantitatively standardized with withaferin A using high-performance thin-layer chromatography. The subacute toxicity study was performed according to OECD guidelines in experimental rats. Nephrotoxicity in rats was induced by a single dose of cisplatin (6 mg/kg, intraperitoneal). Nephroprotective role of W. coagulans fruit extract at different doses had been evaluated. It includes quantification of serum kidney toxicity markers, renal tissue oxidative stress biomarkers and pro-inflammatory cytokines level, DNA fragmentation assay, and histopathological examination of renal tissue.

Results:

Withaferin A was found 3.56 mg/g of W. coagulans fruit extract. It significantly prevented the rise in serum urea and creatinine level and also preserve rat kidneys from oxidative stress and free radical induced DNA damage. Histopathological study showed extract treatment eliminates tubular swelling, cellular necrosis, and protein cast deposition in cisplatin treated kidney tissue. It averted the decline in glutathione content, activities of superoxide dismutase and catalase. These parameters were restored to near normal levels by extract in a dose of 400 mg/kg, per oral. Conclusion: It can be justified that W. coagulans possess dose dependent protective effect against cisplatin induced kidney damages, primarily through its free radical scavenging and anti inflammatory activity

SUMMARY

Authentication and standardization of Withania coagulans fruits

Subacute oral toxicity study

Evaluation of nephroprotective activity against cisplatin-induced nephrotoxicity

DNA fragmentation assay and histopathological examination of kidney tissue in experimental rats.

Abbreviations Used: WHO: World Health Organization, SOD: Superoxide dismutase, CAT: Catalase, HPTLC: High-performance thin layer chromatography, p.o.: Per.oral, i.p.: Intraperitoneal, TNF-α: Tumor necrosis factor-alpha, IL-1β: Interleukin 1-beta, IL-6: Interleukin-6

Chemical-Induced Nephropathy: A Review of the Renal Tubulointerstitial Lesions in Humans

It is almost ironic that one of the major organs that serves to maintain the “internal milieux” by secretion of various toxic agents, can itself become injured in the process. The pattern of morphologic renal injury is nonspecific and can involve any of the components of the kidney, although the injury and subsequent morphologic changes are most commonly noted in the tubules and/or interstitium. Of course, unless the drug/toxin is commonly or regularly noted to be associated with tubular and/or interstitial injury, the association of the drug with the renal changes may be missed and the correlation may not necessarily identify causation. For example, if a drug is associated with a renal injury in a given individual, it may be quite difficult to prove that the drug is the cause of the injury. This scenario is somewhat reminiscent of the test question—is it “true-true-related,” or “true-true-unrelated”? Sometimes it is only by the accrual of a great many examples or correlations, and or dissection of the pathophysiology, can it be shown that the drug is directly related to the observed morphologic (and subsequent clinical) injury. Renal changes induced by chemicals can affect the tubules, interstitium or both. This review of chemically induced nephropathy in humans considers acute tubular necrosis, interstitial nephritis , and tubulointerstitial nephritis or nephropathy. Because the tubules and the interstitium are so intimately related, injury to 1 of these 2 components may eventually lead to injury of the other, resulting in tubulointerstitial disease.

Comparative analysis of gene expression between renal cortex and papilla in nedaplatin-induced nephrotoxicity in rats

To elucidate the mechanism of nephrotoxicity caused by anti-neoplastic platinum complex, nedaplatin (NDP), treatment with a particular focus on the renal papillary toxicity, we analysed the gene expression profiles of two renal regions, the cortex (RC) and the papilla (RP) in rat kidneys. Male Wistar rats received a single administration of 10 mg/kg intravenous NDP or vehicle alone (5% xylitol solution) and were sacrificed six days later. The kidneys were dissected into the RC and RP and used for histopathological and microarray analyses. Histopathologically, NDP caused characteristic renal lesions, such as necrosis, single cell necrosis (with TUNEL TdT-mediated dUTP-biotin nick end labelling-positive) and regeneration/hyperplasia of the epithelial cells in both renal regions. Global gene expression analysis revealed that several genes involved in various functional categories were commonly deregulated in both renal regions, such as apoptosis, cell cycle regulation, DNA metabolism, cell migration/adhesion and cytoskeleton organization or genes induced as a perturbation of oxidative status and calcium homeostasis. Comparative analysis of gene expression between RC and RP revealed that genes encoding several subtypes of cytokeratins were identified as being specifically overexpressed in RP by the NDP treatment. Differential expression patterns of these selected genes observed by microarray analysis were further confirmed by quantitative real time RT-PCR and immunohistochemistry, which demonstrated increased expression of cytokeratins (CKs) 14 and 19 at the epithelium covering RP and/or collecting duct epithelium. Overall, the results contribute to understanding the renal molecular events of NDP-induced nephrotoxicity including novel potential biomarker genes encoding CKs 14 and 19 that may serve as indicators of renal papillary toxicity. Human & Experimental Toxicology (2007) 26, 767—780

Effect of cisplatin on renal brush border membrane enzymes and phosphate transport

Cisplatin (CDDP) is widely used in the treatment of various cancers but its clinical use is associated with dose limiting nephrotoxicity. The present work was carried out to study the effect of administration of CDDP on rat renal brush border membrane (BBM) marker enzymes and inorganic phosphate (Pi) transport across BBM vesicles (BBMV). Animals were administered a single intraperitoneal dose of CDDP (6 mg/kg body weight) or normal saline and then sacrificed 2, 4, 8 and 16 days after this treatment. The administration of CDDP resulted in increased serum creatinine and blood urea nitrogen levels and decreased activity of BBM marker enzymes in the BBM as well as in the homogenates of cortex and medulla. Kinetic studies showed that the Vmaxof the enzymes was decreased in BBM from CDDP treated rats while the Kmremained unchanged. The Na+-gradient dependent transport of Pi across BBMV was also significantly reduced after CDDP treatment. These results strongly suggest that the administration of a single nephrotoxic dose of CDDP results in impairment of the functions of renal BBM.

A Comprehensive Review on the Genetic Regulation of Cisplatin-induced Nephrotoxicity

Cisplatin (CDDP) is a well-known antineoplastic drug which has been extensively utilized over the last decades in the treatment of numerous kinds of tumors. However, CDDP induces a wide range of toxicities in a dose-dependent manner, among which nephrotoxicity is of particular importance. Still, the mechanism of CDDP-induced renal damage is not completely understood; moreover, the knowledge about the role of microRNAs (miRNAs) in the nephrotoxic response is still unknown. miRNAs are known to interact with the representative members of a diverse range of regulatory pathways (including postnatal development, proliferation, inflammation and fibrosis) and pathological conditions, including kidney diseases: polycystic kidney diseases (PKDs), diabetic nephropathy (DN), kidney cancer, and drug-induced kidney injury. In this review, we shed light on the following important aspects: (i) information on genes/proteins and their interactions with previously known pathways engaged with CDDP-induced nephrotoxicity, (ii) information on newly discovered biomarkers, especially, miRNAs for detecting CDDP-induced nephrotoxicity and (iii) information to improve our understanding on CDDP. This information will not only help the researchers belonging to nephrotoxicity field, but also supply an indisputable help for oncologists to better understand and manage the side effects induced by CDDP during cancer treatment. Moreover, we provide up-to-date information about different in vivo and in vitro models that have been utilized over the last decades to study CDDP-induced renal injury. Taken together, this review offers a comprehensive network on genes, miRNAs, pathways and animal models which will serve as a useful resource to understand the molecular mechanism of CDDP-induced nephrotoxicity.

A H 2 S Donor GYY4137 Exacerbates Cisplatin-Induced Nephrotoxicity in Mice

Accumulating evidence demonstrated that hydrogen sulfide (H₂S) is highly involved in inflammation, oxidative stress, and apoptosis and contributes to the pathogenesis of kidney diseases. However, the role of H₂S in cisplatin nephrotoxicity is still debatable. Here we investigated the effect of GYY4137, a novel slow-releasing H₂S donor, on cisplatin nephrotoxicity in mice. Male C57BL/6 mice were pretreated with GYY4137 for 72 h prior to cisplatin injection. After cisplatin treatment for 72 h, mice developed obvious renal dysfunction and kidney injury as evidenced by elevated blood urea nitrogen (BUN) and histological damage. Consistently, these mice also showed increased proinflammatory cytokines such as TNF-α, IL-6, and IL-1β in circulation and/or kidney tissues. Meanwhile, circulating thiobarbituric aid-reactive substances (TBARS) and renal apoptotic indices including caspase-3, Bak, and Bax were all elevated. However, application of GYY4137 further aggravated renal dysfunction and kidney structural injury in line with promoted inflammation, oxidative stress, and apoptotic response following cisplatin treatment. Taken together, our results suggested that GYY4137 exacerbated cisplatin-induced nephrotoxicity in mice possibly through promoting inflammation, oxidative stress, and apoptotic response.

Preventive effect of fermented black ginseng against cisplatin-induced nephrotoxicity in rats

Background

Fermented black ginseng (FBG) is processed ginseng by the repeated heat treatment and fermentation of raw ginseng. The protective effect and mechanism of FBG on cisplatin-induced nephrotoxicity was investigated to evaluate its therapeutic potential.

Methods

The free radical scavenging activity of FBG was measured using 1,1-diphenyl-2-picrylhydrazyl (DPPH). In addition, the protective effect against cisplatin-induced renal damage was tested in rats. FBG was orally administered every day at a dose of 150 mg/kg body weight for 10 d, and a single dose of cisplatin was administered intraperitoneally (7.5 mg/kg body weight) with 0.9% saline on the 4^th d.

Results

The DPPH radical-scavenging activity of FBG (IC₅₀ = 384 μg/mL) was stronger than that of raw ginseng. The improved DPPH radical-scavenging activity was mediated by the generation phenolic compounds. The decreased cell viability by cisplatin was recovered significantly after treatment with FBG in a dose-dependent manner. Then, the protective effect of FBG on cisplatin-induced oxidative renal damage was investigated in rats. The decreased creatinine clearance levels, which are a reliable marker for renal dysfunction in cisplatin-treated rats, were reduced to the normal level after the administration of FBG. Moreover, FBG showed protective effects against cisplatin-induced oxidative renal damage in rats through the inhibition of NF-κB/p65, COX-2, and caspase-3 activation.

Conclusion

These results collectively show that the therapeutic evidence for FBG ameliorates the nephrotoxicity via regulating oxidative stress, inflammation, and apoptosis.

The Protective Effect of γ-aminobutyric Acid on Kidney Injury Induced by Renal Ischemia-reperfusion in Ovariectomized Estradiol-treated Rats

Background:

Renal ischemia-reperfusion injury (IRI) is one of the most important causes of kidney injury, which is possibly gender-related. This study was designed to investigate the role of γ-aminobutyric acid (GABA) against IRI in ovariectomized estradiol-treated rats.

Methods:

Thirty-five ovariectomized Wistar rats were used in six experimental groups. The first three groups did not subject to estradiol treatment and assigned as sham-operated, control, and GABA-treated groups. GABA (50 μmol/kg) and saline were injected in the treated and control groups 30 min before the surgery, respectively. The second three groups received the same treatments but received estradiol valerate (500 μg/kg, intramuscularly) 3 days prior to the surgery. The IRI was induced in the control and treated groups by clamping the renal artery for 45 min and then 24 h of reperfusion. All animals were sacrificed for the measurements.

Results:

The serum levels of creatinine and blood urea nitrogen, kidney weight, and kidney tissue damage score significantly increased in the IRI rats (P < 0.05). GABA significantly decreased the aforementioned parameters (P < 0.05). The uterus weight increased significantly in rats that received estradiol (P < 0.05). Serum and kidney levels of nitrite (nitric oxide metabolite) did not alter significantly. Serum level of malondialdehyde increased significantly in the ovariectomized rats exposed to IRI (P < 0.05).

Conclusions:

It seems that GABA improved IRI in ovariectomized rats. Estradiol was also nephroprotective against IRI. However, co-administration of estradiol and GABA could not protect the kidney against IRI.