Montelukast abrogates rhabdomyolysis-induced acute renal failure via rectifying detrimental changes in antioxidant profile and systemic cytokines and apoptotic factors production

The renoprotective potential of montelukast: a scoping review

Introduction

Kidney damage can result from various factors, leading to structural and functional changes in the kidney. Acute kidney injury (AKI) refers to a sudden decline in kidney function, while chronic kidney disease involves a gradual deterioration lasting more than 3 months. Mechanisms of renal injury include impaired microcirculation, inflammation, and oxidative stress. Cysteinyl-leukotrienes (CysLTs) are inflammatory substances contributing to tissue damage. Montelukast, a leukotriene receptor antagonist, has shown potential renoprotective effects in experimental models of kidney injury.

Methods

The authors conducted a scoping review using PubMed, Scopus, and Web of Science databases to identify relevant studies investigating the impact of montelukast on renal diseases. Articles published until 2022 were included and evaluated for quality. Data extraction and analysis were performed based on predetermined inclusion criteria.

Results

The scoping review included 30 studies from 8 countries. Montelukast demonstrated therapeutic effects in various experimental models of nephrotoxicity and AKI induced by agents such as cisplatin, lipopolysaccharide, diclofenac, amikacin, Escherichia coli, cyclosporine, methotrexate, cobalt-60 gamma radiation, doxorubicin, and cadmium. Studies involving human subjects with nephrotic syndrome, pyelonephritis, and other renal diseases also reported positive outcomes with montelukast treatment. Montelukast exhibited anti-inflammatory, anti-apoptotic, antioxidant, and neutrophil-inhibiting properties, leading to improved kidney function and histopathological changes.

Conclusions

Montelukast shows promise as a renoprotective medication, particularly in early-stage kidney injury. Its ability to mitigate inflammation, oxidative stress, and neutrophil infiltration contributes to its therapeutic effects. Further research is needed to explore the clinical applications and mechanisms underlying the renoprotective action of montelukast.

Inhibition of sepsis-induced pancreatic injury by leukotriene receptor antagonism via modulation of oxidative injury, and downregulation of inflammatory markers in experimental rats

The purpose of this study is to investigate the effect of montelukast on lipopolysaccharide (LPS)-induced pancreatitis. Adult male Wistar rats were divided into 5 groups: normal control, control montelukast, LPS group, and two LPS + montelukast-treated groups. Acute pancreatitis (AP) was induced by a single dose of LPS (6 mg/kg, i.p.), while montelukast was given in two different doses (10 and 20 mg/kg/day) for 3 consecutive days prior to the injection of LPS. AP was demonstrated by significant increases in serum levels of lactate dehydrogenase (LDH) and pancreatic enzymes lipase and amylase. Proinflammatory response activation was evident by elevated serum levels of nitric oxide (NO) and increased pancreatic concentrations of tumor necrosis factor-α (TNF-α), interleukin-1 (IL-1β), and intercellular adhesion molecule-1 (ICAM-1). The activity of myeloperoxidase (MPO), a neutrophil infiltration marker, has also been increased. Oxidative stress was confirmed by significant increases in the concentrations of lipid peroxides measured as thiobarbituric acid reactive substances (TBARS) and decreases in the concentrations of reduced glutathione (GSH) in the pancreatic tissues of animals treated with LPS. Histological examination confirmed the biochemical alterations. Montelukast treatment reversed all these biochemical indices and histopathological changes that LPS induced. Montelukast reduced the increase in serum levels of lipase, amylase, LDH, total nitrite/nitrate, TNF-α, IL-1β, and ICAM-1. MPO activities and TBARS concentrations were also suppressed while GSH content was increased in pancreatic tissues. These results show that montelukast may be a beneficial pharmacological agent in protection against LPS-induced oxidative pancreatic injury by inhibiting neutrophil infiltration, counteracting oxidative stress, and suppressing inflammatory mediators.

Promising Effects of Montelukast for Critically Ill Asthma Patients via a Reduction in Delirium

Background: Montelukast (MTK), a potent antagonist of cysteinyl leukotriene receptor 1, has shown therapeutic promise for the treatment of neuropsychiatric disorders. Delirium, a common complication in critically ill patients, lacks effective treatment. This study aims to explore the impact of pre-intensive care unit (ICU) MTK use on in-hospital delirium incidence and, subsequent, prognosis in critically ill patients. Methods: A retrospective cohort study (n = 6344) was conducted using the MIMIC-IV database. After propensity score matching, logistic/Cox regression, E-value sensitivity analysis, and causal mediation analysis were performed to assess associations between pre-ICU MTK exposure and delirium and prognosis in critically ill patients. Results: Pre-ICU MTK use was significantly associated with reduced in-hospital delirium (OR: 0.705; 95% CI 0.497-0.999; p = 0.049) and 90-day mortality (OR: 0.554; 95% CI 0.366-0.840; p = 0.005). The association was more significant in patients without myocardial infarction (OR: 0.856; 95% CI 0.383-0.896; p = 0.014) and could be increased by extending the duration of use. Causal mediation analysis showed that the reduction in delirium partially mediated the association between MTK and 90-day mortality (ACME: -0.053; 95% CI -0.0142 to 0.0002; p = 0.020). Conclusions: In critically ill patients, MTK has shown promising therapeutic benefits by reducing the incidence of delirium and 90-day mortality. This study highlights the potential of MTK, beyond its traditional use in respiratory disease, and may contribute to the development of novel therapeutic strategies for delirium.

Rhabdomyolysis-induced acute kidney injury and concomitant apoptosis induction via ROS-mediated ER stress is efficaciously counteracted by epigallocatechin gallate

Rhabdomyolysis induced acute kidney injury (RIAKI) is a life-threatening condition responsible for approximately 19-58% of AKI cases worldwide. We performed an intramuscular injection of glycerol (10 mL/kg) in male wistar rats to induce AKI. Epigallocatechin gallate (EGCG) was administered for 3 consecutive days to evaluate its protective effects. We observed significant downregulation in serum creatinine, blood urea nitrogen (BUN) and LDH at different time points on EGCG treatment groups in a dose-dependent manner. Similarly, H&E staining also revealed that EGCG was able to reduce the formation of damaged tubules and tubular necrosis which was prominently spread throughout the kidney tissue of glycerol treatment group. Concomitantly, we observed upregulated inflammation, ER stress and elevated oxidative stress in the glycerol treated group only, which was significantly normalized upon EGCG treatment in both in vitro and in vivo studies. The occurrence of apoptosis in kidney tubules was found to be relatively higher in glycerol treated group and H₂O₂ treated HEK-293 cells. The results obtained after EGCG treatment revealed a significant decrease in apoptotic cell population, which was further validated by immunofluorescence staining against p53 and comet assay in HEK-293 cells and p53 IHC in kidney tissues. Western blotting also revealed a systemic downregulation of intrinsic mitochondrial apoptotic pathway markers such as bax, bcl-2, pro and cleaved caspase 3, caspase 9 and PARP1. Additionally, the results for flow cytometry analysis and TUNEL assay corroborated apoptotic equilibrium. Conclusively, we reckon EGCG as a multi-therapeutic natural product that can be used the for treatment of AKI.

Leukotrienes vs. Montelukast—Activity, Metabolism, and Toxicity Hints for Repurposing

Increasing environmental distress is associated with a growing asthma incidence; no treatments are available but montelukast (MTK)—an antagonist of the cysteinyl leukotrienes receptor 1—is widely used in the management of symptoms among adults and children. Recently, new molecular targets have been identified and MTK has been proposed for repurposing in other therapeutic applications, with several ongoing clinical trials. The proposed applications include neuroinflammation control, which could be explored in some neurodegenerative disorders, such as Alzheimer’s and Parkinson’s diseases (AD and PD). However, this drug has been associated with an increasing number of reported neuropsychiatric adverse drug reactions (ADRs). Besides, and despite being on the market since 1998, MTK metabolism is still poorly understood and the mechanisms underlying neuropsychiatric ADRs remain unknown. We review the role of MTK as a modulator of leukotriene pathways and systematize the current knowledge about MTK metabolism. Known toxic effects of MTK are discussed, and repurposing applications are presented comprehensively, with a focus on AD and PD.

Kidney in the net of acute and long-haul coronavirus disease 2019: a potential role for lipid mediators in causing renal injury and fibrosis

PURPOSE OF REVIEW

Severe COVID-19 disease is often complicated by acute kidney injury (AKI), which may transition to chronic kidney disease (CKD). Better understanding of underlying mechanisms is important in advancing therapeutic approaches.

RECENT FINDINGS

SARS-CoV-2-induced endothelial injury initiates platelet activation, platelet-neutrophil partnership and release of neutrophil extracellular traps. The resulting thromboinflammation causes ischemia-reperfusion (I/R) injury to end organs. Severe COVID-19 induces a lipid-mediator storm with massive increases in thromboxane A2 (TxA2) and PGD2, which promote thromboinflammation and apoptosis of renal tubular cells, respectively, and thereby enhance renal fibrosis. COVID-19-associated AKI improves rapidly in the majority. However, 15-30% have protracted renal injury, raising the specter of transition from AKI to CKD.

SUMMARY

In COVID-19, the lipid-mediator storm promotes thromboinflammation, ischemia-reperfusion injury and cytotoxicity. The thromboxane A2 and PGD2 signaling presents a therapeutic target with potential to mitigate AKI and transition to CKD. Ramatroban, the only dual antagonist of the thromboxane A2/TPr and PGD2/DPr2 signaling could potentially mitigate renal injury in acute and long-haul COVID. Urgent studies targeting the lipid-mediator storm are needed to potentially reduce the heavy burden of kidney disease emerging in the wake of the current pandemic.

Thalidomide reduces glycerol-induced acute kidney injury by inhibition of NF-κB, NLRP3 inflammasome, COX-2 and inflammatory cytokines

Acute kidney injury (AKI) is an important clinical complication of rhabdomyolysis. The inflammatory processes are involved in the pathogenesis of AKI induced by rhabdomyolysis. Thalidomide is an anti-inflammatory agent that has been used in the treatment of inflammatory disorders. The aim of this study was to investigate the therapeutic effect of thalidomide and its underlying mechanisms on a mouse model of rhabdomyolysis-induced AKI. Mice were injected with a single dose of glycerol (50%, 10 ml/kg, im) to induce AKI, and treated with thalidomide (40 and 80 mg/kg/day, orally) for 2 days. Renal tissue and blood samples were collected for histological and biochemical analysis. In thalidomide treated mice, blood urea nitrogen (BUN) (59.3 ± 19.6 vs. 223 ± 33 mg/dl), plasma creatinine (0.58 ± 0.3 vs. 1.28 ± 0.3 mg/dl), relative kidney weight (0.93 ± 0.13% vs. 1.22 ± 0.1%) and histopathological damage (1.5 ± 0.8 vs. 3.3 ± 1.1 score) were significantly lower as compared to the glycerol group. The results also showed that the levels of malondialdehyde (MDA) (0.13 ± 0.02 vs. 0.2 ± 0.01 µM/mg), myeloperoxidase (MPO) (0.1 ± 0.05 vs. 0.25 ± 0.02 U/mg) and the expression of nuclear factor kappa B (NF-κB) (1.7-fold), NLRP3 inflammasome (1.4-fold) and cyclooxygenase (COX)-2 (3-fold) in renal tissue were significantly lower in thalidomide treated group than those in the glycerol group. Thalidomide treatment resulted in lower renal pro-inflammatory cytokines tumor necrosis factor (TNF)-α (6.7 ± 0.8 vs. 12.3 ± 1.2 ng/ml), interleukin (IL)-1β (3.2 ± 0.5 vs. 5.1 ± 0.3 pg/mg), IL-6 (24.7 ± 2.4 vs. 33 ± 3 pg/mg) and transforming growth factor (TGF)-β1 (0.6 ± 0.17 vs. 1.56 ± 0.24 ng/ml) than those in the glycerol treated mice. In addition the levels of monocyte chemoattractant protein (MCP)-1 (9.5 ± 1 vs. 12.8 ± 1.1 pg/mg) and intercellular adhesion molecule (ICAM)-1 (22.8 ± 7.8 vs. 53.3 ± 5.5 pg/mg) were significantly lower in renal tissue of mice treated with thalidomide as compared to the glycerol treated mice. In conclusion these data revealed that thalidomide may be a potential therapeutic approach against rhabdomyolysis-induced AKI through inhibition of inflammatory responses.

The Leukotriene Receptor Antagonist Montelukast Reduces Alpha-Synuclein Load and Restores Memory in an Animal Model of Dementia with Lewy Bodies

Dementia with Lewy bodies (DLB) represents a huge medical need as it accounts for up to 30% of all dementia cases, and there is no cure available. The underyling spectrum of pathology is complex and creates a challenge for targeted molecular therapies. We here tested the hypothesis that leukotrienes are involved in the pathology of DLB and that blocking leukotrienes through Montelukast, a leukotriene receptor antagonist and approved anti-asthmatic drug, might alleviate pathology and restore cognitive functions. Expression of 5-lipoxygenase, the rate-limiting enzyme for leukotriene production, was indeed elevated in brains with DLB. Treatment of cognitively deficient human alpha-synuclein overexpressing transgenic mice with Montelukast restored memory. Montelukast treatment resulted in modulation of beclin-1 expression, a marker for autophagy, and in a reduction in the human alpha-synulcein load in the transgenic mice. Reducing the protein aggregation load in neurodegenerative diseases might be a novel model of action of Montelukast. Moreover, this work presents leukotriene signaling as a potential drug target for DLB and shows that Montelukast might be a promising drug candidate for future DLB therapy development.

Renal protective effect of nebivolol in rat models of acute renal injury: role of sodium glucose co-transporter 2

BACKGROUND

Upregulation of the sodium glucose co-transporter (SGLT2) is implicated in acute renal injury (ARI) progression and is regulated by extracellular signal-regulated kinase (ERK), hypoxia-inducible factor 1 alpha (HIF1α) or prostaglandin E2 (PGE2). This study aimed to assess the possible protective effect of nebivolol on renal ischemia/reperfusion (IR) and glycerol-induced ARI targeting SGLT2 via modulating the ERK-HIF1α pathway.

METHODS

Rats were divided into control, sham, IR or nebivolol-treated group, in which rats were treated with nebivolol (10 mg/kg) for 3 days prior to the induction of IR. The rats were subjected to renal ischemia by bilateral clamping of the pedicles for 45 min, followed by 24 h reperfusion. Another group of rats received the vehicle or nebivolol (10 mg/kg) for 3 days followed by injection of 50% glycerol (8 ml/kg, IM) or saline. Kidney function tests, systolic blood pressure (SBP), oxidative stress markers [malondialdehyde (MDA) and NADPH oxidase] and kidney levels of nitric oxide (NO), inducible nitric oxide synthase (iNOS), HIF1α, ERK phosphorylation and PGE2 were determined. Additionally, renal sections were used for histological grading of renal injury and immunological expression of SGLT2.

RESULTS

ARI rats showed significantly increased SBP, poor kidney function tests, increased oxidative stress, iNOS, NO, HIF1α levels, decreased PGE2 and ERK phosphorylation and upregulation of SGLT2 expression. Nebivolol treatment protected against the kidney damage both on the biochemical and histological levels.

CONCLUSION

Nebivolol has a direct renoprotective effect, at least in part, by down-regulating SGLT2 possibly via modulating HIF1α, ERK activity and PGE2 production.

Radioprotective effects of montelukast, a selective leukotriene CysLT1 receptor antagonist, against nephrotoxicity induced by gamma radiation in mice

PURPOSE

In this study, we evaluated the renal protective effects of montelukast (MLK) against ionizing radiation (IR) induced nephrotoxicity in mice.

MATERIALS AND METHODS

Radioprotective effects of MLK were assessed by biochemical analysis including measurements of kidney malondialdehyde (MDA), reduced glutathione (GSH), and serum creatinine and urea levels. Besides, for further evaluation of protective effects of MLK on renal system, ^99m Tc-dimercaptosuccinic acid (DMSA) has been applied. The total antioxidant capacity of MLK was measured by using 1,1-diphenyl-2-picryl hydrazyl radical reagents and compared with butylated hydroxyl toluene standard antioxidant.

RESULTS

The biochemical evaluation revealed that better results have been achieved for the groups administered with MLK than the only radiation group. Besides only IR-treated mice group, those treated with MLK demonstrated a significant decrease in urea and creatinine levels. Statistically, significant differences of MDA and SHG levels (P < .05) were found between the radiation group and MLK plus IR-treated group. Also, ^99m Tc-DMSA kidney uptake value (%ID/g) was observed lower for MLK plus IR-treated mice group than only radiation-treated mice group.

CONCLUSIONS

According to our findings, MLK has a potential role to be used as a renal protective agent against gamma radiation in radiotherapy.

Montelukast abrogates prednisolone-induced hepatic injury in rats: Modulation of mitochondrial dysfunction, oxidative/nitrosative stress, and apoptosis

The aim of this study was to investigate the protective effect of montelukast (MTK) against prednisolone-induced hepatic injury in rats. Twenty-eight male albino rats were categorized into four equal groups. Group I served as the control group; group II: rats orally received prednisolone (5 mg·kg-1 ·d-1 ) for 30 days; groups III and IV: rats orally received MTK at 10 and 20 mg·kg-1 ·d-1 , respectively, simultaneously with prednisolone for 30 days. Serum liver enzymes, hepatic mitochondrial function, oxidative/nitrosative stress, and inflammatory and apoptotic markers were evaluated, and the results were confirmed by histopathological examination. MTK showed significant hepatic protection evidenced by alleviated histological lesion and improvement of mitochondrial function, oxidative/nitrosative stress, and inflammatory and apoptotic changes induced by prednisolone, with more profound protection in higher MTK dose (20 mg·kg-1 ). In view of these findings, we can conclude that MTK may have hepatoprotective potential, beyond its therapeutic value for asthmatic patients during their course of corticosteroid therapy.

Leukotrienes and kidney diseases

Purpose of review

This review will critically highlight the role of leukotrienes as mediators of renal diseases and drug nephrotoxicity. It will also discuss the recently identified mechanism of cysteinyl leukotrienes induction and action, and will propose clinical implementation of these findings.

Recent findings

Since last reviewed in 1994, leukotrienes were shown to mediate drug-associated nephrotoxicity, transplant rejection and morbidity in several models of renal diseases. Although leukotrienes may be released by various infiltrating leukocytes, a recent study demonstrated that cytotoxic agents trigger production of leukotriene C₄ (LTC₄) in mouse kidney cells by activating a biosynthetic pathway based on microsomal glutathione-S-transferase 2 (MGST2). LTC₄ then elicits nuclear accumulation of hydrogen peroxide-generating NADPH oxidase 4, leading to oxidative DNA damage and cell death. LTC₄ inhibitors, commonly used as systemic asthma drugs, alleviated drug-associated damage to proximal tubular cells and attenuated mouse morbidity.

Summary

Cysteinyl leukotrienes released by mast cells trigger the symptoms of asthma, including bronchoconstriction and vasoconstriction. Therefore, effective leukotriene inhibitors were approved as orally administered asthma drugs. The findings that leukotrienes mediate the cytotoxicity of nephrotoxic drugs, and are involved in numerous renal diseases, suggest that such asthma drugs may ameliorate drug-induced nephrotoxicity, as well as some renal diseases.

Enhanced lipoxygenase/LTD4 signaling accounts for the exaggerated hypertensive and nephrotoxic effects of cyclosporine plus indomethacin in rats

The combined use of cyclosporine (CSA) and nonsteroidal antiinflammatory drugs (NSAIDs) causes exaggerated rises in systolic blood pressure (SBP) and nephrotoxicity. We examined whether these influences relate to the arachidonate/5-lipoxygenase (LOX) pathway. Rats were treated with CSA (20 mg kg^-1 day^-1), indomethacin (5 mg kg^-1 day^-1), or their combination for 10 days. Changes in SBP and renal biochemical/histopathological characteristics along with leukotriene levels were determined in rats treated with or without LT receptor antagonists. CSA or indomethacin caused: (i) renal tubular atrophy and interstitial fibrosis, (ii) increases in serum creatinine, blood urea nitrogen (BUN), and renal LTD4, LTB4, TNF-α, TGF-β1, and caspase-3, and (iii) decreases in renal PGE2 and total antioxidant capacity (TAC). SBP measured by tail-cuff plethysmography was increased by CSA but not indomethacin. These effects were mostly intensified in rats treated with CSA plus indomethacin. The co-treatment with montelukast (cysteinyl LT receptor blocker), but not ONO-4057 (LTB4 receptor blocker), ameliorated CSA/indomethacin-evoked hypertension, renal structural/biochemical deterioration, and LTD4 levels. Moreover, montelukast exhibited a greater capacity in reversing inflammatory, oxidative, apoptotic, and fibrotic abnormalities induced by CSA/indomethacin. Overall, lipoxygenase/LTD4 upregulation contributes to the exaggerated hypertension and nephrotoxicity caused by CSA/indomethacin. The therapeutic potential of cysteinyl LT receptor antagonism in rectifying CSA/NSAIDs-evoked anomalies is warranted.

Zileuton alleviates acute cisplatin nephrotoxicity: Inhibition of lipoxygenase pathway favorably modulates the renal oxidative/inflammatory/caspase-3 axis

OBJECTIVE

The current study investigated for the first time the possible beneficial effect of zileuton, a selective 5-lipoxygenase inhibitor (5-LOX), against cisplatin-induced acute renal failure.

METHODOLOGY

Male Sprague-Dawley rats (180-200 g) were administered cisplatin once (5 mg/kg, i.p.) alone or combined with oral zileuton (10 mg/kg, given twice; 1 h before and 12 h after cisplatin).

RESULTS

Compared with control rats, acute cisplatin administration caused significant increases of BUN (33.76 ± 7.74 vs 61.88 ± 11.35 mg/dl), serum creatinine (0.61 ± 0.21 vs 1.56 ± 0.28 mg/dl), renal levels of MDA (6.40 ± 1.04 vs 20.52 ± 2.18 nmol/g tissue), NOx (3.45 ± 1.20 vs 17.70 ± 2.27 nmol/g tissue), TNF-α (6.71 ± 0.66 vs 23.71 ± 3.41 pg/g tissue), MPO (0.87 ± 0.09 vs 3.12 ± 0.41 U/mg tissue protein) and renal caspase-3 activity (2.81 ± 0.37 vs 12.70 ± 2.94 U/mg tissue protein). Whereas, total SOD activity (1.99 ± 0.53 vs 0.79 ± 0.06 U/mg tissue protein) and IL-10 (110.98 ± 19.70 vs 62.34 ± 14.42 pg/g tissue) were significantly decreased. Cisplatin-induced nephrotoxicity was further confirmed histopathologically (tubular necrosis, cystic dilatation of renal tubules, vacuolar degeneration of renal tubular epithelium with perivascular oedema, and interstitial fibrosis). These changes were accompanied by alteration in 5-LOX pathway manifested as elevated renal levels of 5-LOX, LTD4 and LTB4. Simultaneous administration of zileuton to the cisplatin-treated rats reversed the deleterious renal insults and restored the measured parameters near to control values.

CONCLUSIONS

These data establish the first experimental evidence that zileuton abrogates cisplatin nephrotoxicity in rats probably via the inhibition of detrimental actions of 5-LOX products, thus favorably affecting renal oxidative/inflammatory/caspase-3 axis. Based on current findings, the therapeutic prospect of zileuton for this purpose is recommended.

Effect of curcumin on glycerol-induced acute kidney injury in rats

The aim of this study was to investigate the protective role and underlying mechanisms of curcumin on glycerol-induced acute kidney injury (AKI) in rats. Glycerol (10 ml/kg BW, 50% v/v in sterile saline, i.m.) was used to induce AKI, followed by curcumin (200 mg/kg/day, p.o.) administration for 3 days. To confirm renal damage and the effects of curcumin on AKI, serum BUN, Scr, and CK as well as renal SOD, MDA, GSH-Px were measured. Additionally, morphological changes were identified by H&E staining and transmission electron microscopy. The expression of several factors including chemotactic factor MCP-1, proinflammatory cytokines including TNF-α and IL-6, as well as the kidney injury markers, as Kim-1 and Lipocalin-2 were also assessed using q-PCR. Finally, cell apoptosis in renal tissue was detected using in situ TUNEL apoptosis fluorescence staining and expression of proteins associated with apoptotic, oxidative stress and lipid oxidative related signaling pathways were detected using immunohistochemical staining and western blot. The results showed that curcumin exerts renoprotective effects by inhibiting oxidative stress in rhabdomyolysis-induced AKI through regulation of the AMPK and Nrf2/HO-1 signaling pathways, and also ameliorated RM-associated renal injury and cell apoptosis by activating the PI3K/Akt pathway.

Biological Membrane-Packed Mesenchymal Stem Cells Treat Acute Kidney Disease by Ameliorating Mitochondrial-Related Apoptosis

The mortality of rhabdomyolysis-induced AKI remains high because no effective therapy exists. We investigated a new therapeutic method using MSCs. The aim of this study was to investigate the therapeutic potential and anti-apoptotic mechanisms of action of MSCs in the treatment of AKI induced by glycerol in vivo and in vitro. We used Duragen as a biological membrane to pack MSCs on the glycerol-injured renal tissue in vivo. The anti-apoptotic mechanism was investigated. In vitro, HK-2 cells were incubated with ferrous myoglobin and MSCs-conditioned medium, followed by cell proliferation and apoptosis assays. We founded that packing MSCs on the injured renal tissue preserved renal function, ameliorated renal tubular lesions, and reduced apoptosis in the mice with glycerol-induced AKI. The MSC-conditioned medium improved HK-2 cell viability and inhibited apoptosis. These effects were reversed by the PI3K inhibitor LY294002. Biological membrane packing of MSCs on the renal tissue has a therapeutic rescue function by inhibiting cell apoptosis in vivo. MSCs protect renal cells from apoptosis induced by myoglobin in vitro. We have thus demonstrated MSCs reduced rhabdomyolysis-associated renal injury and cell apoptosis by activating the PI3K/Akt pathway and inhibiting apoptosis.

Hybrid polymeric matrices for oral modified release of Desvenlafaxine succinate tablets

Purpose: Desvenlafaxine succinate (DSV) is a water soluble anti-depressant drug, which is rapidly absorbed after oral administration exaggerating its side effects. The current work aimed to prepare controllable release DSV matrix to reduce DSV side effects related to its initial burst. Methods: Fifteen DSV matrix formulations were prepared using different polymers, polymer/drug ratios and matrix excipients and characterized using Differential Scanning Calorimetry (DSC), infrared (IR) spectroscopy, water uptake and in vitro DSV release. The release kinetics were calculated to determine the drug release mechanism. Ex-vivo DSV absorption via rat intestinal mucosal cells and the calculation of the apparent permeability coefficient (P_app) were performed using everted sac technique. Results: Maltodextrin was the best matrix excipient (F7 and F10) showing acceptable decrease in the initial burst compared to the innovator. The addition of negatively charged polymers sodium carboxy methyl cellulose (SCMC) or sodium alginate resulted in an interaction that was proved by DSC and IR findings. This interaction slowed DSV release. F10 showed an excellent absorption of more than 80% of DSV after 4 h and the highest similarity factor with the innovator (84.7). Conclusion: A controllable release pattern of DSV was achieved using Methocel, Maltodextrin and SCMC. The obtained results could be used as a platform to control the release of cationic water soluble drugs that suffer from side effects associated with their initial burst after oral administration.

Protective Effects of Vasodilatory Βeta-Blockers Carvedilol and Nebivolol against Glycerol Model of Rhabdomyolysis-Induced Acute Renal Failure in Rats

BACKGROUND

Rhabdomyolysis (RM)-induced acute renal failure (ARF) accounts for about 10-40% of all cases of ARF.

AIM

The present study investigated the possible protective effect of two nitric oxides (NO)-releasing third generation β-blockers, carvedilol (Carv) and nebivolol (Nebi), against RM-mimicking glycerol (Gly)-induced ARF in rats.

MATERIAL AND METHODS

After 24 h dehydration, rats received a single dose of 50% Gly (8 ml/kg, im). They were treated with vehicle, Carv (2.5 mg/kg/day, po) or Nebi (10 mg/kg, po) for 3 successive days starting from an hour prior to Gly injection. Evaluation of blood pressure and locomotor activity was performed during the experiment. 72 h following Gly administration, total protein in the urine, serum levels of creatinine, blood urea nitrogen, sodium and potassium as well as the renal contents of malondialdehyde, reduced glutathione and NO were assessed, together with a histopathological examination of renal tissues.

RESULTS

Carv and Nebi attenuated Gly-induced renal dysfunction and histopathological alterations. They decreased the Gly-induced oxidative stress and increased renal NO concentration. Restoration of normal blood pressure and improvement of locomotor activity were also observed.

CONCLUSION

The results clearly demonstrate protective effects of Carv and Nebi against renal damage involved in RM-induced ARF and suggest a role of their antioxidant and NO-releasing properties.

Montelukast as an add-on treatment in steroid dependant nephrotic syndrome, randomised-controlled trial

BACKGROUND

The underlying mechanisms of nephrotic syndrome (NS) are still under debate and the need for more effective and less toxic treatment is challenging. We aimed to evaluate the efficacy of montelukast, a leukotriene receptor antagonist as an add-on therapy, and to explore the leukotriene (LT) biology in steroid-dependent nephrotic syndrome (SDNS).

METHODS

A randomized controlled trial was conducted including 32 patients with SDNS who were randomly assigned to receive standard steroid treatment only [low-dose steroid (LDS) group] or standard steroid therapy plus montelukast (Montelukast group). Urine protein/creatinine ratio, serum albumin, creatinine, cholesterol, and plasma LTs (LTB4/C4/D4/E4) were evaluated in all patients before and after treatment.

RESULTS

After treatment, both groups showed a significant decrease of LTB4 and LTC4/D4/E4. Further, the Montelukast group showed a significant decrease in serum creatinine and a significant increase in diastolic blood pressure and protein/creatinine ratio. It also showed a marked decrease in plasma LTC4/D4/E4 compared to the LDS group, although not statistically significant.

CONCLUSIONS

Our findings highlight the effect of montelukast on renal function, but suggest that the clinical and laboratory efficacy of the addition of montelukast to steroids in maintenance treatment of SDNS is debatable.

Additive Renoprotection by Pioglitazone and Fenofibrate against Inflammatory, Oxidative and Apoptotic Manifestations of Cisplatin Nephrotoxicity: Modulation by PPARs

Nephrotoxicity is a major side effect for the antineoplastic drug cisplatin. Here, we employed pharmacological, biochemical, and molecular studies to investigate the role of peroxisome proliferator-activated receptors (PPARs) in cisplatin nephrotoxicity. Rats were treated with a single i.p. dose of cisplatin (5 mg/kg) alone or combined with pioglitazone (PPARγ agonist), fenofibrate (PPARα agonist), pioglitazone plus fenofibrate, or thalidomide (Tumor necrosis factor-α inhibitor; TNF-α). Cisplatin nephrotoxicity was evidenced by rises in renal indices of functional (blood urea nitrogen, BUN, and creatinine), inflammatory (TNF-α, interleukin 6, IL-6), oxidative (increased malondialdehyde, MDA, and decreased superoxide dismutase, SOD and nitric oxide metabolites, NOx), apoptotic (caspase 3), and histological (glomerular atrophy, acute tubular necrosis and vacuolation) profiles. Cisplatin effects were partly abolished upon concurrent exposure to pioglitazone, fenofibrate, or thalidomide; more renoprotection was observed in rats treated with pioglitazaone plus fenofibrate. Immunostaining showed that renal expressions of PPARα and PPARγ were reduced by cisplatin and restored to vehicle-treated values after simultaneous treatment with pioglitazone or fenofibrate. Fenofibrate or pioglitazone renoprotection remained unaltered after concurrent blockade of PPARα (GW6471) and PPARγ (GW9662), respectively. To complement the rat studies, we also report that in human embryonic kidney cells (HEK293 cells), increases caused by cisplatin in inflammatory, apoptotic, and oxidative biomarkers were (i) partly improved after exposure to pioglitazone, fenofibrate, or thalidomide, and (ii) completely disappeared in cells treated with a combination of all three drugs. These data establish that the combined use of pioglitazone and fenofibrate additively improved manifestations of cisplatin nephrotoxicity through perhaps GW6471/GW9662-insensitive mechanisms.

Endothelin ETA receptor/lipid peroxides/COX-2/TGF-β1 signalling underlies aggravated nephrotoxicity caused by cyclosporine plus indomethacin in rats

BACKGROUND AND PURPOSE

Cyclosporine (CSA) and non-steroidal anti-inflammatory drugs (NSAIDs) are co-prescribed for some arthritic conditions. We tested the hypothesis that this combined regimen elicits exaggerated nephrotoxicity in rats via the up-regulation of endothelin (ET) receptor signalling.

EXPERIMENTAL APPROACH

The effects of a 10 day treatment with CSA (20 mg · kg(-1) · day(-1)), indomethacin (5 mg · kg(-1) · day(-1)) or their combination on renal biochemical, inflammatory, oxidative and structural profiles were assessed. The roles of ETA receptor and COX-2 pathways in the interaction were evaluated.

KEY RESULTS

Oral treatment with CSA or indomethacin elevated serum urea and creatinine, caused renal tubular atrophy and interstitial fibrosis, increased renal TGF-β1, and reduced immunohistochemical expressions of ETA receptors and COX-2. CSA, but not indomethacin, increased renal ET-1, the lipid peroxidation product malondialdehyde (MDA) and GSH activity. Compared with individual treatments, simultaneous CSA/indomethacin exposure caused: (i) greater elevations in serum creatinine and renal MDA; (ii) loss of the compensatory increase in GSH; (iii) renal infiltration of inflammatory cells and worsening of fibrotic and necrotic profiles; and (iv) increased renal ET-1 and decreased ETA receptor and COX-2 expressions. Blockade of ETA receptors by atrasentan ameliorated the biochemical, structural, inflammatory and oxidative abnormalities caused by the CSA/indomethacin regimen. Furthermore, atrasentan partly reversed the CSA/indomethacin-evoked reductions in the expression of ETA receptor and COX-2 protein.

CONCLUSIONS AND IMPLICATIONS

The exaggerated oxidative insult and associated dysregulation of the ETA receptor/COX-2/TGF-β1 signalling might account for the aggravated nephrotoxicity caused by the CSA/indomethacin regimen. The potential renoprotective effect of ETA receptor antagonism might be exploited therapeutically.

Celecoxib offsets the negative renal influences of cyclosporine via modulation of the TGF-β1/IL-2/COX-2/endothelin ET(B) receptor cascade

Endothelin (ET) signaling provokes nephrotoxicity induced by the immunosuppressant drug cyclosporine A (CSA). We tested the hypotheses that (i): celecoxib, a selective cyclooxygenase-2 (COX-2) inhibitor, counterbalances renal derangements caused by CSA in rats and (ii) the COX-2/endothelin ET(B) receptor signaling mediates the CSA-celecoxib interaction. Ten-day treatment with CSA (20 mg/kg/day) significantly increased biochemical indices of renal function (serum urea, creatinine), inflammation (interleukin-2, IL-2) and fibrosis (transforming growth factor-β₁, TGF-β₁). Histologically, CSA caused renal tubular atrophy along with interstitial fibrosis. These detrimental renal effects of CSA were largely reduced in rats treated concurrently with celecoxib (10 mg/kg/day). We also report that cortical glomerular and medullary tubular protein expressions of COX-2 and ET(B) receptors were reduced by CSA and restored to near-control values in rats treated simultaneously with celecoxib. The importance of ET(B) receptors in renal control and in the CSA-celecoxib interaction was further verified by the findings (i) most of the adverse biochemical, inflammatory, and histopathological profiles of CSA were replicated in rats treated with the endothelin ETB receptor antagonist BQ788 (0.1 mg/kg/day, 10 days), and (ii) the BQ788 effects, like those of CSA, were alleviated in rats treated concurrently with celecoxib. Together, the data suggest that the facilitation of the interplay between the TGF-β1/IL-2/COX-2 pathway and the endothelin ET(B) receptors constitutes the cellular mechanism by which celecoxib ameliorates the nephrotoxic manifestations of CSA in rats.

Renoprotective effects of montelukast, a cysteinyl leukotriene receptor antagonist, against methotrexate-induced kidney damage in rats

Methotrexate (MTX) is a cytotoxic chemotherapeutic agent used for treatment of several cancers. Nephrotoxicity, an adverse side effect of high-dose MTX, is attributed to abnormal production of reactive oxygen species (ROS), inflammatory mediators, and neutrophil infiltration. Montelukast (MON) is a cysteinyl leukotriene receptor antagonist. Recently, it has gained a considerable interest as a ROS scavenger and inflammatory modulator. In this study, we investigated the effect of MON against MTX-induced nephrotoxicity. Rats were divided into four groups: control group, MON group (10 mg/kg, orally), MTX group (20 mg/kg, i.p., single injection), and MON + MTX group (MON was administered 5 days before and 5 days after MTX administration). At the end of the experiment, serum was collected for analysis of blood urea nitrogen (BUN) and creatinine. Glutathione (GSH), lipid peroxides (malondialdehyde), tumor necrosis factor alpha (TNF-α) levels, superoxide dismutase, myeloperoxidase activities, and nuclear factor kappa beta (NF-κB) protein expression were determined in renal tissues. In addition, kidney tissues were examined histopathologically and immunohistochemically for NF-κB. MTX administration produced acute renal damage as indicated from severe elevation in BUN and serum creatinine. The role of oxidative stress and inflammatory mechanisms in MTX-induced nephrotoxicity was evidenced from the unbalance in tissue oxidative parameters, increased TNF-α levels, and NF-κB expression in renal tissues. On the other hand, MON significantly reduced the toxic effects of MTX as indicted from normalization of kidney-specific parameters, oxidative stress, and inflammatory mediators. This data was further supported by histopathological studies. Thus, co-administration of MON may be promising in alleviating the systemic side effects of MTX.

Pretreatment with hydrogen-rich saline reduces the damage caused by glycerol-induced rhabdomyolysis and acute kidney injury in rats

BACKGROUND

Rhabdomyolysis is a leading cause of acute kidney injury. The pathophysiological process involves oxidative stress and inflammation. Hydrogen-rich saline (HRS) is an antioxidant and anti-inflammatory. This study explored the protective effect of pretreatment with HRS on the development of glycerol-induced rhabdomyolysis acute kidney injury.

MATERIALS AND METHODS

Forty-eight rats were randomly divided into four equal groups. Group 1 served as the control, group 2 was given 50% glycerol (10 mL/kg, intramuscular), group 3 was given glycerol after 7 d pretreatment with high dose HRS (10 mL/kg/d, intraperitoneal), and group 4 was given glycerol after 7 d pretreatment with low dose HRS (5 mL/kg/d, intraperitoneal). Renal health was monitored by serum creatinine (Cr), urea, and histologic analysis; rhabdomyolysis was monitored by creatine kinase (CK) levels; and oxidative stress was monitored by kidney tissue reactive oxygen species (ROS), malondialdehyde, 8-hydroxydeoxyguanosine (8-OH-dG), superoxide dismutase (SOD), and glutathione peroxidase (GSH-PX) levels. Inflammation was monitored by interleukin 6 (IL-6) and tumor necrosis factor alpha (TNF-α) evaluation.

RESULTS

Glycerol administration resulted in an increase in the mean histologic damage score, serum Cr, urea and CK, kidney tissue ROS, malondialdehyde, 8-OH-dG, GSH-PX, IL-6, and TNF-α, and a decrease in kidney tissue superoxide dismutase activity. All these factors were significantly improved by both doses of HRS, but the mean histologic damage score, urea, Cr, CK, ROS, 8-OH-dG, GSH-PX, IL-6, and TNF-α for the high dose HRS treatment group were even lower.

CONCLUSIONS

Pretreatment by HRS ameliorated renal dysfunction in glycerol-induced rhabdomyolysis by inhibiting oxidative stress and the inflammatory response.

Effects of montelukast on subepithelial/peribronchial fibrosis in a murine model of ovalbumin induced chronic asthma

Montelukast, a leukotriene receptor antagonist, is used commercially as a maintenance treatment for asthma and to relieve allergic symptoms. In this study, we evaluated the protective effects of montelukast against the airway inflammation and fibrosis using a murine model of ovalbumin (OVA) induced chronic asthma. The animals received OVA challenge three times a week for 4 weeks. Montelukast (30 mg/kg) was administrated orally once a day for 4 weeks. The administration of montelukast caused a reduction in elevated interleukin (IL)-4, IL-13, eotaxin, immunoglobulin (Ig), inflammatory cell infiltration into the airways, and mucus production after repeated OVA challenges. To investigate the antifibrotic mechanism of montelukast, we examined the expression of profibrotic mediators, including vascular endothelial growth factor (VEGF), transforming growth factor (TGF)-β1, and Smad3 proteins in the lung tissue using western blotting and immunohistochemistry. The administration of montelukast reduced the overexpression of profibrotic proteins in the lung tissue, which was confirmed by immnunohistochemistry. These results are consistent with a histopathological examination of lung tissue with Masson's trichrome stain. In conclusion, the administration of montelukast reduced airway inflammation and pulmonary fibrosis by reducing the release of Th2 cytokines and the expression of VEGF, TGF-β1/Smad3 in the lung tissue.