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

Reno-protective effect of nicorandil and pentoxifylline against potassium dichromate-induced acute renal injury via modulation p38MAPK/Nrf2/HO-1 and Notch1/TLR4/NF-κB signaling pathways

BACKGROUND

Occupational and environmental exposure to chromium compounds such as potassium dichromate (PDC) (K2Cr2O7) has emerged as a potential aetiologic cause for renal disease through apoptotic, and inflammatory reactions. The known potent antioxidants such as nicorandil (NIC) and/or pentoxifylline (PTX) were studied for their possible nephroprotective effect in PDC-treated rats.

METHODS

Forty male Wistar rats were divided into five groups; control, PDC group, NIC+PDC, PTX+PDC group, and combination+PDC group. Nephrotoxicity was evaluated histopathologically and biochemically. Invasive blood pressure, renal function parameters urea, creatinine, uric acid and albumin, glomerular filtration rate markers Cys-C, Kim-1 and NGAL, inflammatory markers IL-1β, IL-6, TNF-α, TGF-β, COX-II, p38MAPK, NF-κB and TLR4, oxidative stress SOD, GSH, MDA, MPO, HO-1 and Nrf2 and apoptotic mediators Notch1 and PCNA were evaluated. Besides, renal cortical histopathology was assayed as well.

RESULTS

PDC led to a considerable increase in indicators for kidney injury, renal function parameters, invasive blood pressure, oxidative stress, and inflammatory markers. They were markedly reduced by coadministration of PDC with either/or NIC and PTX. The NIC and PTX combination regimen showed a more significant improvement than either medication used alone. Our results demonstrated the nephroprotective effect of NIC, PTX, and their combined regimen on PDC-induced kidney injury through suppression of oxidative stress, apoptosis, and inflammatory response.

CONCLUSION

Renal recovery from PDC injury was achieved through enhanced MAPK/Nrf2/HO-1 and suppressed Notch1/TLR4/NF-κB signaling pathways. This study highlights the role of NIC and PTX as effective interventions to ameliorate nephrotoxicity in patients undergoing PDC toxicity.

Nicorandil mitigates arsenic trioxide-induced lung injury via modulating vital signalling pathways SIRT1/PGC-1α/TFAM, JAK1/STAT3, and miRNA-132 expression

BACKGROUND AND PURPOSE

Nicorandil, a selective opener of potassium channels, used to treat angina, has drawn attention for its potential in mitigating lung injury, positioning it as a promising therapeutic approach to treat drug-induced lung toxicity. This study aimed to explore the protective role of nicorandil in arsenic trioxide (ATO)-induced lung injury and to elucidate the underlying mechanistic pathways.

EXPERIMENTAL APPROACH

We assessed the effects of nicorandil (15 mg·kg-1, p.o.) in a rat model of pulmonary injury induced by ATO (5 mg·kg-1, i.p.). The assessment included oxidative stress biomarkers, inflammatory cytokine levels, and other biomarkers, including sirtuin-1, sirtuin-3, STAT3, TFAM, and JAK in lung tissue. Histological examination using H&E staining and molecular investigations using western blotting and PCR techniques were conducted.

KEY RESULTS

In our model of lung injury, treatment with nicorandil ameliorated pathological changes as seen with H&E staining, reduced tissue levels of toxicity markers, and exerted significant antioxidant and anti-inflammatory actions. On a molecular level, treatment with nicorandil down-regulated JAK, STAT3, PPARγ, Nrf2, VEGF, p53, and micro-RNA 132 while up-regulating Sirt1, 3, TFAM, AMPK, and ERR-α in lung tissue.

CONCLUSIONS AND IMPLICATIONS

The results presented here show nicorandil as a significant agent in attenuating lung injury induced by ATO in a rodent model. Nonetheless, further clinical studies are warranted to strengthen these findings.

Monoterpene linalool restrains gentamicin-mediated acute kidney injury in rats by subsiding oxidative stress, apoptosis, and the NF-κB/iNOS/TNF-α/IL-1β pathway and regulating TGF-β

The clinical use of gentamicin (GM) is restricted by its nephrotoxic effects. This study aimed for the first time to elucidate the ameliorative effects of the monoterpene linalool (Lin) against GM-mediated acute kidney injury in rats. A total of thirty-two rats were subdivided into four equal groups: control (saline), Lin (100 mg/kg/day), GM (100 mg/kg/day), and GM + Lin (100 and 100 mg/kg/day). Lin and GM were intraperitoneally administered for 12 days. Our results illustrated that Lin ameliorated GM-mediated renal histopathological abnormalities and reduced serum urea and creatinine levels in rats exposed to GM. Lin treatment mitigated oxidative stress in nephrotoxic animals as manifested by reducing serum and renal levels of malondialdehyde and increasing the activities of serum and renal glutathione peroxidase and renal catalase. Moreover, Lin markedly inhibited GM-triggered inflammation by downregulating NF-κB, iNOS, TNF-α, and IL-1β and reducing renal myeloperoxidase activity and nitric oxide levels. Interestingly, Lin repressed GM-induced apoptosis, as reflected by a marked downregulation of Bax and caspase-3 expression, concurrent with the upregulation of Bcl2 expression. Finally, Lin administration led to a significant downregulation of TGF-β expression in nephrotoxic animals. In summary, Lin ameliorated GM-mediated nephrotoxicity in rats, at least through its antioxidant, anti-inflammatory, and anti-apoptotic activities and by modulating TGF-β.

Ursodeoxycholic acid alleviates atopic dermatitis-associated inflammatory responses in HaCaT and RBL-2H3 cells and DNCB/DFE-treated mice

AIMS

Ursodeoxycholic acid (UDCA) is a hydrophilic dihydroxy bile acid used for cholestatic liver disease and exhibits antioxidant, antitumor, and anti-inflammatory effects. However, its potential effects on atopic dermatitis (AD) have not been elucidated. This study aimed to evaluate the efficacy of UDCA in inhibiting the inflammatory response and alleviating lesions in AD-like mice.

MAIN METHODS

To investigate the efficacy of UDCA in AD-like inflammatory responses, tumor necrosis factor-alpha (TNF-α)- and interferon-gamma (IFN-γ)-stimulated HaCaT cells and anti-dinitrophenyl immunoglobulin E (DNP-IgE)- and human serum albumin (HSA)-stimulated RBL-2H3 cells were used to investigate the levels of inflammatory factors and their mechanisms. AD-like lesions were induced by applying DNCB/DFE to mice. The effect of UDCA administration in AD-like mice was analyzed by assessing organ weight, serum IgE and inflammatory cytokine levels, and histopathological changes using immunohistochemical and immunofluorescent staining.

KEY FINDINGS

In HaCaT cells, UDCA significantly diminished TARC, MDC, MCP-1, and IL-6 expression by inhibiting the phosphorylation of nuclear NF-κB and cytoplasmic IκB, and also increased the levels of skin barrier protein. In RBL-2H3 cells, UDCA reduced β-hexosaminidase and IL-4 levels. In AD-like mice, UDCA suppressed organ hypertrophy, ear edema, SCORAD index, DFE-specific IgE levels, inflammatory cytokine levels, skin hypertrophy, mast cell invasion, skin barrier loss, and thymic stromal lymphopoietin-positive areas.

SIGNIFICANCE

UDCA suppressed the expression of pro-inflammatory cytokines by keratinocytes and mast cells. It also alleviated atopy by suppressing symptoms without organ toxicity in AD-like mice. UDCA may be an effective and safe treatment for AD.

Amelioration of Acute Alcoholic Liver Injury via Attenuating Oxidative Damage and Modulating Inflammation by Means of Ursodeoxycholic Acid-Zein Nanoparticles

Ursodeoxycholic acid (UDCA) has been broadly adopted for the clinical treatment of hepatic and biliary diseases; however, its poor water-solubility becomes an obstacle in wide applications. To overcome these challenges, herein, a two-tier UDCA-embedded system of zein nanoparticles (NPs) along with a polyelectrolyte complex was designed under facile conditions. Both the UDCA-zein NPs and their inclusion microcapsules showed a spherical shape with a uniform size. A typical wall plus capsule/core structure was formed in which UDCA-zein NPs distributed evenly in the interior. The UDCA inclusion microcapsules had an encapsulation rate of 67% and were released in a non-Fickian or anomalous transport manner. The bioavailability and efficacy of UDCA-zein NPs were assessed in vivo through the alcoholic liver disease (ALD) mouse model via intragastric administration. UDCA-zein NPs ameliorated the symptoms of ALD mice remarkably, which were mainly exerted through attenuation of antioxidant stress levels. Meanwhile, it notably upregulated the intestinal tight junction protein expression and improved and maintained the integrity of the mucosal barrier effectively. Collectively, with the improvement of bioavailability, the UDCA-zein NPs prominently alleviated the oxidative damage induced by alcohol, modulating the inflammation so as to restore ALD. It is anticipated that UDCA-zein NPs have great therapeutic potential as sustained-nanovesicles in ALD treatment.

Further insights into the impact of rebamipide on gentamicin-induced nephrotoxicity in rats: modulation of SIRT1 and β-catenin/cyclin D1 pathways

Gentamicin (GM) is an effective antibiotic administered to treat acute Gram-negative infections. Nevertheless, its clinical application is limited due to nephrotoxicity. Therefore, our research aimed to investigate the potential renoprotective impact of rebamipide (RBM), a gastroprotective drug, on GM-induced kidney damage in rats, as well as putative nephroprotective pathways. RBM was orally administered (100 mg/kg/d for 14 d) commencing 7 d before the administration of GM (100 mg/kg/d, intraperitoneally). Nephrotoxicity was elucidated, and the silent information regulator 1 (SIRT1) and β-catenin/cyclin D1 pathways were assessed. GM induced a significant elevation in the serum levels of creatinine, blood urea nitrogen (BUN), and kidney injury molecule-1 (KIM-1), as well as the relative kidney index. In addition, GM increased lipid peroxidation and lowered total antioxidant capacity (TAC) level and superoxide dismutase (SOD) activity. GM administration also demonstrated a significant amplification in tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1β), nuclear factor-κappa B p65 (NF-κB p65), p38 mitogen-activated protein kinase (p38 MAPK), and caspase-3 kidney levels, as well as B-cell lymphoma 2 (Bcl-2)-associated X protein (Bax)/Bcl-2 ratio. Notably, RBM treatment amended all these changes induced by GM. Furthermore, the potential role of SIRT1 and β-catenin-dependent signaling pathways in GM-induced renal injury was assessed. Our findings showed that GM-treated rats demonstrated a substantial decrease in SIRT1, nuclear factor E2-related factor 2 (Nrf2), and heme oxygenase-1 (HO-1) along with an increase in β-catenin, forkhead box O-3a (FOXO-3a), and cyclin D1 protein expressions. RMB treatment markedly attenuated the deterioration caused by GM on these pathways. Additionally, RBM alleviated the GM-induced deleterious kidney tissue histopathology. In conclusion, our findings have verified that RBM can halt GM-induced renal injury by partly modulating SIRT1 and β-catenin pathways.

The potential role of upregulated PARP-1/RIPK1 expressions in amikacin-induced oxidative damage and nephrotoxicity in Wistar rats

This study aimed to investigate the gene expression levels associated with nephrotoxic action of amikacin, as well as the post-treatment effect of diuretics on its nephrotoxic effects. Sixty male rats were divided equally into six groups, including the control group receiving saline intra-peritoneally (ip), and the five treated groups including therapeutic and double therapeutic dose groups, injected ip (15 and 30 mg/kg b.wt./day) respectively for seven days, and another two rat groups treated as therapeutic and double therapeutic dose groups then administered the diuretic orally for seven days and the last group received amikacin ip at a rate of 15 mg/kg/day for seven days, then given free access to water without diuretics for another seven days and was kept as a self-recovery group. Amikacin caused kidney injury, which was exacerbated by the double therapeutic dose, as evidenced by abnormal serum renal injury biomarkers, elevated renal MDA levels, inhibition of renal catalase and SOD enzyme activities, with renal degenerative and necrotic changes. Moreover, comet assays also revealed renal DNA damage. Interestingly, amikacin administration markedly elevated expression levels of the PARP-1, RIP1, TNF-α, IL-1β, and iNOS genes as compared to the control group. However, compared to the self-recovery group, post-amikacin diuretic treatment modulates amikacin-induced altered findings and alleviates amikacin nephrotoxic effects more efficiently. Our findings suggested the potential role of PARP-1 and RIPK1 expressions that influence the expression of proinflammatory cytokines such as IL-1β and TNF-α by exaggerating oxidative stress which may contribute to the pathogenesis of amikacin-induced nephrotoxicity.

Insight into Nephrotoxicity and Processing Mechanism of Arisaema erubescens (Wall.) Schott by Metabolomics and Network Analysis

Background

Arisaematis Rhizome (AR) has been used as a damp-drying, phlegm-resolving, wind-expelling, pain-alleviating, and swelling-relieving drug for thousands of years. However, the toxicity limits its clinical applications. Therefore, AR is usually processed (Paozhi in Chinese) prior to clinical use. In this study, the integration of ultra-high performance liquid chromatography-quadrupole/ time-of-flight mass spectrometry-based metabolomics and network analysis was adopted to investigate the metabolic shifts induced by AR and explore the processing mechanism.

Materials and Methods

Extracts of crude and processed AR products (1g/kg) were intragastrically administered to rats once daily for four consecutive weeks. The renal function was evaluated by blood urea nitrogen, creatinine, interleukin-1 beta (IL-1β) and tumor necrosis factor-alpha (TNF-α), malondialdehyde (MDA), super oxide dismutase (SOD), the ratio of glutathione/glutathione disulfide (GSH/GSSH), glutathione peroxidase (GSH-Px) and histopathological examination. Furthermore, the chemical composition of AR was clarified by ultra-high performance liquid chromatography-quadrupole/ time-of-flight mass spectrometry, after which the integration of metabolomics and network analysis was adopted to investigate the metabolic shifts induced by AR and explore the processing mechanism.

Results

Crude AR caused renal damage by stimulating inflammation and oxidative stress, as confirmed by the increased production of IL-1β, TNF-α and MDA, and decreased levels of SOD, GSH/GSSH and GSH-Px. Processing with ginger juice, alumen and bile juice alleviated the damage to kidney. Metabolomics results showed that a total of 35 potential biomarkers enriched in amino acid metabolism, glycerophospholipid metabolism, fatty acid-related pathways, etc. were deduced to be responsible for the nephrotoxicity of AR and the toxicity-reducing effect of processing.

Conclusion

This work provided theoretical and data support for the in-depth study of the processing mechanism, showing that processing reduces AR nephrotoxicity through multiple metabolic pathways.

Exogenous glutathione protects against gentamicin-induced acute kidney injury by inhibiting NF-κB pathway, oxidative stress, and apoptosis and regulating PCNA

This study was designed, for the first time, to examine the possible nephroprotective effects of exogenous glutathione (EGSH) (100 mg/kg, intraperitoneally) on gentamicin-induced acute kidney injury (GM-induced AKI). EGSH reduced renal histopathological changes, inflammatory cell infiltration, and improved renal dysfunction in rats with AKI. EGSH ameliorated GM-induced renal oxidative stress by promoting the renal activities of catalase, glutathione peroxidase, and superoxide dismutase and diminishing renal malondialdehyde and serum nitric oxide levels. Interestingly, EGSH inhibited intrinsic apoptosis by downregulating Bax and caspase-3 and upregulating Bcl2 in the kidney of rats with AKI. EGSH decreased GM-induced inflammatory response as reflected by a remarkable decrease in the protein expressions of NF-κB-p65, IL-6, TNF-α, and iNOS and a considerable diminish in myeloperoxidase activity. Finally, EGSH markedly declined proliferative cell nuclear antigen (PCNA) protein expression in the animals with AKI. In summary, EGSH alleviated AKI in rats intoxicated with GM, partially by inhibiting oxidative stress, NF-κB pathway, and intrinsic apoptosis and regulating PCNA.

Protective effect of Cistanche deserticola on gentamicin-induced nephrotoxicity in rats

Objective

Gentamicin (GM) is a commonly used aminoglycoside antibiotic, however, renal toxicity has limited its usage. The present study was designed to evaluate the ameliorative effect of Cistanche deserticola on GM-induced nephrotoxicity in rats.

Methods

The nephrotoxicity in rats was induced by intraperitoneal administration of GM (100 mg/kg) for 10 consecutive days. Glomerular filtration rate, blood urea nitrogen, creatinine and kidney histopathology were detected to assess the GM-induced nephrotoxicity. The oxidative stress (catalase, superoxide dismutase, glutathione and malondialdehyde) was assessed. The inflammatory response (tumor necrosis factor-α, interleukin-6, myeloperoxidase and nuclear factor-kappa B) and apoptotic marker (Bax and Bcl-2) were also evaluated.

Results

The results showed that water and 75% ethanol extracts of C. deserticola (named CDW and CDE, respectively) (100, 200 and 400 mg/kg) in combination with GM could recover the reduction of glomerular filtration rate and enhance the renal endogenous antioxidant capability induced by GM. The increase in the expression of renal inflammatory cytokines (tumor necrosis factor-α and interleukin-6), nuclear protein of nuclear factor-kappa B (p65) and the activity of myeloperoxidase induced by GM was significantly decreased upon CDW or CDE treatment. In addition, CDW or CDE treatment could decrease the Bax protein expression and increase the Bcl-2 protein expression in GM-induced nephrotoxicity in rats significantly.

Conclusion

The study demonstrated that C. deserticola treatment could attenuate kidney dysfunction and structural damage in rats induced by GM through the reduction of inflammation, oxidative stress and apoptosis.

Expression of ER stress markers (GRP78 and PERK) in experimental nephrotoxicity induced by cisplatin and gentamicin: roles of inflammatory response and oxidative stress

This study aimed to establish the relationship between two endoplasmic reticulum (ER) stress proteins, glucose-regulated protein 78 (GRP78/BiP) and PKR-like endoplasmic reticulum kinase (PERK), and oxidative stress markers in cisplatin (CIS)-induced and gentamicin (GEN)-induced nephrotoxicity.The study consisted of five groups: control (saline solution only), CIS D2 (2.5 mg/kg for 2 days), CIS D7 (2.5 mg/kg for 7 days), GEN D2 (160 mg/kg for 2 days), and GEN D7 (160 mg/kg for 7 days). All rats were sacrificed 24 h after the last injection for standard clinical chemistry, and ultrastructural and histological evaluation of the kidney.CIS and GEN increased blood urea nitrogen (BUN) and serum creatinine (Cr) levels, as well as total oxidant status (TOS), while decreasing total antioxidant status (TAS) level in CIS D7 and GEN D7 groups. Histopathological and ultrastructural findings were also consistent with renal tubular damage. In addition, expression of markers of renal inflammation (tumor necrosis factor-α (TNF-α) and interleukin 1β (IL-1β)) and ER stress markers (GRP78 and PERK) was significantly increased in the kidney tissue of rats treated with CIS and GEN for 7 days.These findings suggest that CIS and GEN administration for 7 days aggravates nephrotoxicity through the enhancement of oxidative stress, inflammation, and ER stress-related markers. As a result, the recommended course of action is to utilize CIS and GEN as an immediate but brief induction therapy, stopping after 3 days and switching to other drugs instead.

The Amomum tsao-ko Essential Oils Inhibited Inflammation and Apoptosis through p38/JNK MAPK Signaling Pathway and Alleviated Gentamicin-Induced Acute Kidney Injury

The clinical application of gentamicin may lead to acute kidney injury (AKI), and the nephrotoxicity of gentamicin is related to the pathological mechanism of several oxidative and inflammatory cytokines. Plant-derived essential oils have good anti-inflammatory and antioxidant properties. This study aimed to clarify the protective effect of Amomum tsao-ko essential oils (AOs) on gentamicin-induced AKI in rats and its possible mechanism. The rat AKI model was induced by intraperitoneal injection of gentamicin. After 14 days of oral AO treatment, the renal function and pathological changes of the kidney tissues were evaluated, and the level of kidney tissue oxidative stress was detected. The content of inflammatory cytokines was measured by ELISA. The expression of ERK1/2, JNK1/2, p38, NF-κB, caspase-3, and Bax/Bcl-2 proteins were estimated by Western blot analysis. The results showed that taking AO reduced the contents of serum urea and creatinine in AKI rats and improve the pathological changes and oxidative stress of the kidney tissue in rats. At the same time, AO reduced inflammation and apoptosis during AKI by regulating the MAPK pathway. The data show that AO has a protective effect on the kidneys and may be a potential drug for treating kidney injury.

The role of inflammation in cadmium nephrotoxicity: NF-κB comes into view

Kidney diseases are major health problem and understanding the underlined mechanisms that lead to kidney diseases are critical research points with a marked potential impact on health. Cadmium (Cd) is a heavy metal that occurs naturally and can be found in contaminated food. Kidneys are the most susceptible organ to heavy metal intoxication as it is the main route of waste excretion. The harmful effects of Cd were previously well proved. Cd induces inflammatory responses, oxidative injury, mitochondrial dysfunction and disturbs Ca²⁺ homeostasis. The nuclear factor-kappa B (NF-κB) is a cellular transcription factor that regulates inflammation and controls the expression of many inflammatory cytokines. Therefore, great therapeutic benefits can be attained from NF-κB inhibition. In this review we focused on certain compounds including cytochalasin D, mangiferin, N-acetylcysteine, pyrrolidine dithiocarbamate, roflumilast, rosmarinic acid, sildenafil, sinapic acid, telmisartan and wogonin and certain plants as Astragalus Polysaccharide, Ginkgo Biloba and Thymus serrulatus that potently inhibit NF-κB and effectively counteracted Cd-associated renal intoxication. In conclusion, the proposed NF-κB involvement in Cd-renal intoxication clarified the underlined inflammation associated with Cd-nephropathy and the beneficial effects of NF-κB inhibitors that make them the potential to substantially optimize treatment protocols for Cd-renal intoxication.

Chloroquine Attenuates Oxidative Stress in Gentamicin-Induced Nephrotoxicity in Rats

The wider application of gentamicin is limited by potential adverse effects (nephrotoxicity and ototoxicity). The goal of our study was to investigate the effects of chloroquine on biochemical and oxidative stress parameters in gentamicin-induced nephrotoxicity in rats. Animals were randomly divided into 1 of 5 groups. First was Sham group (0.9% NaCl) (n = 8); second group received gentamicin (n = 8); while third (n = 8), fourth (n = 8) and fifth group (n = 8) received gentamicin and chloroquine in a dose of 0.3, 1 and 3 mg/kg, respectively. The urea and creatinine levels were significantly lower in chloroquine treated groups in doses of 0.3 mg/kg and 1 mg/kg (P < 0.001). Total oxidant status and the oxidative stress index showed significantly lower values in all chloroquine treated groups (P < 0.001; P < 0.005). Malondialdehyde was lower in chloroquine treatment in doses of 0.3 mg/kg (P < 0.005) and 3 mg/kg (P < 0.05). Chloroquine treatment markedly reduced the level of superoxide dismutase in doses of 1 mg/kg (P < 0.01) and 3 mg/kg (P < 0.05). Our study showed that chloroquine attenuates gentamicin-induced nephrotoxicity in rats regarding biochemical and oxidative stress parameters.

Renoprotective effect of vinpocetine against ischemia/reperfusion injury: Modulation of NADPH oxidase/Nrf2, IKKβ/NF-κB p65, and cleaved caspase-3 expressions

Ischemia/reperfusion injury (IRI) during kidney transplantation is a serious clinical problem with a high mortality rate and a lack of therapy. Therefore, there is a need to improve the ability of the kidney to tolerate IRI during transplantation. This study aimed to investigate the possible protective effect of vinpocetine; a derivative of vincamine alkaloid; against renal IRI in rats with the elucidation of the involved mechanisms. Vinpocetine (25 mg/kg; i.p.) was administered for 10 successive days before the induction of ischemia by bilateral clamping of both renal pedicles for 45 min followed by 24 h of reperfusion. Blood and renal tissue samples were then collected for biochemical, molecular, and histopathological investigations. Vinpocetine significantly reduced serum creatinine and blood urea nitrogen levels in rats subjected to IRI. It also reduced mRNA expression of NADPH oxidase and renal content of malondialdehyde, while enhanced Nrf2 protein expression and renal content of reduced glutathione. The suppression of the provoked inflammatory response was evident by the downregulation of IKKβ and NF-κB p65 protein expressions, as well as their downstream inflammatory markers; tumor necrosis factor-α, interleukin-6, and myeloperoxidase. In addition, vinpocetine reduced protein expression of the apoptotic executioner cleaved caspase-3. These nephroprotective effects were confirmed by the improvement in histopathological features. Collectively, the protective effect of vinpocetine against IRI could be attributed to modulation of NADPH oxidase/Nrf2, IKKβ/NF-κB p65, and cleaved caspase-3 expressions. Thus, vinpocetine could improve oxidant/antioxidant balance, suppress triggered inflammatory response, and promote renal cell survival after IRI.

Cinnamic acid ameliorate gentamicin-induced liver dysfunctions and nephrotoxicity in rats through induction of antioxidant activities

This study was the first to evaluate the possible protective effects of cinnamic acid (CA) against Gentamicin (GM) induced liver and kidney dysfunctions in rats. Adult male Wistar rats were randomly assigned to 4 equal groups (n = 8): Control group (saline, 0.5 ml/day), CA group (CA, 50 mg/kg/day), GM group (GM, 100 mg/kg/day), and GM + CA group (100 & 50 mg/kg/day). Following 12 days of treatments, blood and 24 h urine samples were collected and kidneys were taken out for biochemical, histopathological, and molecular studies. Following CA treatment, renal function markers and transaminases activities including serum urea (59.92%) and creatinine (50.41%), protein excretion rate (43.67%), and serum activities of aspartate aminotransferase (AST) (54.34%) and alanine aminotransferase (ALT) (47.26%) significantly reduced in the treated group as compared with the GM group (P < 0.05). Also, CA could significantly ameliorate the levels of triglyceride (29.70%), cholesterol (13.02%), very low-density lipoprotein (29.69%) and high-density lipoprotein-cholesterol (7.28%). CA could also attenuate oxidative stress through a decrease of serum malondialdehyde (MDA) (50.86%) and nitric oxide (NO) (0.85%) and an increase of renal catalase (CAT) (196.14%) and glutathione peroxidase (GPX) activities (45.88%) as well as GPX mRNA expression (44.42-fold) as compared with the GM group (P < 0.05). Moreover, histopathological evaluations revealed attenuated tubular damages and reduced inflammatory cellular infiltration in CA treated animals. Overall, CA alleviates GM-induced nephrotoxicity and alterations in transaminases activities in rats through its antioxidant activities.

Agomelatine prevents gentamicin nephrotoxicity by attenuating oxidative stress and TLR-4 signaling, and upregulating PPARγ and SIRT1

Kidney injury is a relatively common complication of the use of aminoglycosides. Inflammation and oxidative stress play a key role in gentamicin (GM) nephrotoxicity. We investigated the protective effect of the melatonergic agonist agomelatine (AGM) on GM nephrotoxicity, emphasizing the involvement of TLR-4 signaling, SIRT1 and PPARγ. Rats received 25 mg/kg AGM for 15 days and 100 mg/kg GM for eight days starting at day 7. Elevated serum creatinine, urea and Kim-1 along with multiple histological alterations in the kidney were observed in GM-intoxicated rats. Malondialdehyde (MDA), TNF-α, IL-1β, nitric oxide (NO) and myeloperoxidase (MPO) were increased, and GSH, SOD and catalase were decreased in the kidney of GM-intoxicated rats. Treatment with AGM significantly ameliorated the kidney function biomarkers, prevented tissue injury, decreased inflammatory cytokines, MDA, NO and MPO, and boosted antioxidants. In addition, AGM suppressed the expression of TLR-4, NF-κB p65, p38 MAPK, ERK-1, VCAM-1 and iNOS, whereas upregulated SIRT1 and PPARγ in the kidney of GM-intoxicated rats. In conclusion, AGM prevented GM nephrotoxicity in rats by attenuating oxidative injury and inflammation. AGM suppressed TLR-4 signaling, enhanced antioxidants and upregulated SIRT1 and PPARγ in the kidney of GM-induced rats.

A Complementary Herbal Product for Controlling Giardiasis

Giardiasis is an intestinal protozoal disease caused by Giardia lamblia. The disease became a global health issue due to development of resistance to commonly used drugs. Since many plant-derived products have been used to treat many parasitic infestations, we aimed to assess the therapeutic utility of Artemisia annua (A. annua) for giardiasis. We showed that NO production was significantly reduced whereas serum levels of IL-6, IFN-γ, and TNF-α were elevated in infected hamsters compared to uninfected ones. Additionally, infection resulted in increased numbers of intraepithelial lymphocytes and reduced villi heights, goblet cell numbers, and muscularis externa thickness. We also showed that inducible NO synthase (iNOS) and caspase-3 were elevated in the intestine of infected animals. However, treatment with A. annua significantly reduced the intestinal trophozoite counts and IEL numbers, serum IL-6, IFN-γ, and TNF-α, while increasing NO and restoring villi heights, GC numbers, and ME thickness. Moreover, A. annua treatment resulted in lower levels of caspase-3, which indicates a protective effect from apoptotic cell death. Interestingly, A. annua therapeutic effects are comparable to metronidazole. In conclusion, our results show that A. annua extract is effective in alleviating infection-induced intestinal inflammation and pathological effects, which implies its potential therapeutic utility in controlling giardiasis.

Targeting KEAP1/Nrf2, AKT, and PPAR-γ signals as a potential protective mechanism of diosmin against gentamicin-induced nephrotoxicity

AIM

Gentamicin (GM) is an aminoglycoside antibiotic effectively used for severe/life-threatening infections. However, the clinical application of GM is limited by nephrotoxic side effects. Diosmin (DS) is a flavonoid with a wide range of bioactivities. However, its therapeutic potential in GM-induced nephrotoxicity remains unclear.

METHODS

Rats received GM (100 mg/kg, i.p.) for 7 days either separately or in combination with oral DS (50 mg/kg).

RESULTS

GM injection disrupted kidney function along with oxidant/antioxidant imbalance. Also, GM significantly decreased renal nuclear factor erythroid 2-related factor 2 (Nrf2), glutamyl cysteine synthetase (GCLC), heme oxygenase-1 (HO-1), superoxide dismutase3 (SOD-3), protein kinase B (AKT), and p-AKT expressions along with Kelch-like ECH-associated protein 1 (KEAP1) up-regulation. On the contrary, DS administration significantly attenuated GM-induced kidney dysfunction and restored kidney oxidant/antioxidant status. In addition, co-treatment with DS plus GM significantly enhanced Nrf2, GCLC, HO-1, SOD3, AKT, and p-AKT expressions along with KEAP1 down-regulation. Additionally, GM-treated rats exhibited a significant decrease in the expressions of renal peroxisome-proliferator activated receptor-gamma (PPAR-γ) and this reduction was alleviated by DS treatment. Furthermore, histopathological findings demonstrated that DS significantly reduced the GM-induced histological abrasions. Besides, an in-silico study was conducted to confirm our biochemical results. Interestingly, in-silico results strongly supported our biochemical investigation by studying the binding affinity of DS to KEAP1, AKT, and PPAR-γ proteins.

SIGNIFICANCE

DS could be a promising protective agent against GM-induced nephrotoxicity through targeting of KEAP1/Nrf2/ARE, AKT, and PPAR-γ signaling pathways.

Rebamipide potentially mitigates methotrexate-induced nephrotoxicity via inhibition of oxidative stress and inflammation: A molecular and histochemical study

Methotrexate (MTX) is a widely used chemotherapeutic agent; nevertheless, the nephrotoxicity associated with its use has limited its clinical use. Rebamipide (REB) is a gastro-protective agent with diverse promising biological activities. Here, we investigated the renoprotective effects of REB against MTX-induced nephrotoxicity in rats. Male Wistar rats were allocated into four groups: the normal control group, the REB group (100 mg kg^-1 day^-1 , PO, for 12 days), the MTX group (which received a single injection of 20 mg/kg, ip), and the REB + MTX group (which received 100 mg kg^-1 day^-1 REB for 7 days before and 5 days after being injected with 20 mg/kg MTX). Interestingly, MTX triggered kidney injury, characterized by renal dysfunction along with histopathological alterations. Moreover, increased reactive oxygen species level and inflammatory response were detected in the kidney of MTX-treated rats. However, REB prevented MTX-induced oxidative kidney injury and boosted an antioxidant balance. Mechanistically, REB markedly activated the NRF-2 protein and upregulated the expression of both SIRT-1 and FOXO-3 genes. Additionally, REB administration strongly inhibited the inflammatory response by downregulating both NF-κB-p65 and TLR-4. Finally, the coadministration of REB and MTX activated the mTOR/PI3K/AKT signaling pathway. Simultaneously, REB treatment attenuated the reduction in glomerular size, the widening of the capsular spaces, and the tubular cell damage due to MTX administration. Taken together, these results indicate the potential of REB as adjuvant therapy to prevent nephrotoxicity in patients receiving MTX treatment.

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

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

Umbelliferone attenuates gentamicin-induced renal toxicity by suppression of TLR-4/NF-κB-p65/NLRP-3 and JAK1/STAT-3 signaling pathways

Nephrotoxicity is the most common adverse effect of gentamicin (GNT). This study aimed to investigate the possible nephroprotective effect of umbelliferone (UMB), against GNT-induced nephrotoxicity. Rats were allocated into the control group; UMB group (50 mg/kg/day, P.O. for 15 days); GNT group (100 mg/kg/day, i.p., for 8 days); and GNT + UMB group. By the end of the experimental period, serum creatinine, urea, and uric acid as well as urine KIM-1 and urine albumin/creatinine ratio were evaluated to estimate kidney function. Moreover, tissue samples were collected for assessment of ERK1/2, p-ERK1/2, TLR-4, p38 MAPK, NF-κB-p65, NLRP-3, IkBα, TNF-α, IL-1β, JAK1, STAT-3, p-STAT, and cleaved caspase-3. In support, the histopathological examination of renal tissues was performed. UMB improves kidney function through regulation of renal serum biomarkers, with alleviations of histological abrasions induced by GNT. Besides, UMB downregulates renal protein expressions of ERK1/ERK2, TLR-4, and p38MAPK, with subsequent suppression of NF-κB-p65/NLRP-3 inflammasome and JAK1/STAT-3 pathways as well as cleaved caspase-3. In parallel, UMB induced IkBα upregulation. Collectively, UMB markedly amended all GNT-induced renal changes. These nephroprotective outcomes could be attributed to its ability to impede TLR-4/NF-κB-p65/NLRP-3 inflammasome and JAK1/STAT-3 pathways activation, as well as to its anti-inflammatory property.

Ursodeoxycholic acid abrogates gentamicin-induced hepatotoxicity in rats: Role of NF-κB-p65/TNF-α, Bax/Bcl-xl/Caspase-3, and eNOS/iNOS pathways

AIM

The present study focused on the possible underlying protective mechanisms of UDCA against GNT-induced hepatic injury.

METHODS

For achieving this goal, adult male rats were allocated into 4 groups: normal control (received vehicle), GNT (100 mg/kg, i.p. for 8 days), UDCA (60 mg/kg, P.O. for 15 days), and GNT + UDCA (received UDCA for 15 days and GNT started from the 7th day and lasted for 8 days).

RESULTS

The results revealed that UDCA significantly improved GNT-induced hepatic injury, oxidative stress, apoptosis, and inflammatory response. Interestingly, UDCA inhibited apoptosis by marked down-regulation of the Bax gene, Caspase-3, and cleaved Caspase-3 protein expressions while the level of Bcl-xL gene significantly increased. Moreover, UDCA strongly inhibited the inflammatory response through the down-regulation of both NF-κB-p65 and TNF-α accompanied by IL-10 elevation. Furthermore, the obtained results ended with the restored of mitochondria function that confirmed by electron microscopy. Histological analysis showed that UDCA remarkably ameliorated the histopathological changes induced by GNT.

SIGNIFICANCE

UDCA may be a promising agent that can be used to prevent hepatotoxicity observed in GNT treatment. This effect could be attributed to, at least in part, the ability of UDCA to modulate NF-κB-p65/TNF-α, Bax/Bcl-xl/Caspase-3, and eNOS/iNOS signaling pathways.

Hydrogen sulfide renal protective effects: possible link between hydrogen sulfide and endogenous carbon monoxide in a rat model of renal injury

Hydrogen sulfide (H2S), along with nitric oxide (NO) and carbon monoxide (CO), proved to have renoprotective effects in various renal diseases. Therefore, this study investigated the renoprotective effect of H2S, in a renal injury model, and its crosstalk with other gasotransmitters such as CO. Thirty-two adult rats were divided into four groups: control, gentamicin (GEN)-treated, GEN + sodium hydrosulfide (NaHS), and GEN + NaHS + zinc protoporphyrin (ZnPP) groups. GEN was used to induce renal injury, NaHS is a water-soluble H2S, and ZnPP is a selective heme oxygenase-1 (HO-1) inhibitor used to inhibit CO synthesis in vivo. NaHS improved kidney functions in the GEN group as evidenced by significantly lower levels of renal injury markers: serum urea, creatinine, uric acid, urinary albumin excretion, and urinary albumin/creatinine. Moreover, NaHS administration to the GEN-treated group significantly lowered renal levels of NO and tumor necrosis factor-α with an increase in total antioxidant, HO-1, and interleukin-10 levels. Furthermore, NaHS administration downregulated the GEN-induced overexpression of the renal inducible nitric oxide synthase (iNOS) and upregulated the suppression of endothelial nitric oxide synthase (eNOS) with improvement in the histological examination and periodic acid Schiff (PAS) staining. However, this improvement in kidney function produced by NaHS was reduced by combination with ZnPP but still improved as compared with the GEN-treated group. The renoprotective effects of H2S can be through its effects on renal tissue antioxidants, pro-inflammatory and anti-inflammatory cytokines, and expression of eNOS and iNOS which can be partially dependent on CO pathway via induction of HO-1 enzyme.