Apocynin abrogates methotrexate-induced nephrotoxicity: role of TLR4/NF-κB-p65/p38-MAPK, IL-6/STAT-3, PPAR-γ, and SIRT1/FOXO3 signaling pathways

Perindopril Dampens Cd-induced Nephrotoxicity by Suppressing Inflammatory Burden, Ang II/Ang 1-7, and Apoptosis Signaling Pathways

Cadmium (Cd) is one of the most abundant toxic heavy metals, and its exposure is linked to serious kidney intoxication, a major health problem. Evidence reported that inflammatory damage is a key factor in Cd renal intoxication. Perindopril (PER) is an angiotensin-converting enzyme inhibitor approved for treating hypertension and other cardiovascular problems. Significantly, RAS activation results in inflammatory damage. Our study aimed to examine the renoprotective effects of PER in Cd-induced nephrotoxicity, the impact of inflammation, and the underlying molecular mechanisms. PER was given at a dose of 1 mg/kg per day. Cd was injected at a dose of 1.2 mg/kg, as a single dose. Treatment with PER led to a significant decrease in serum levels of urea, creatinine, uric acid, and urine albumin/creatinine ratio. PER effectively mitigated inflammation by decreasing MPO, NO, IL-1β, IL-6, and INF-γ levels mediated by downregulating NF-κB expression and suppressing JAK-1 and STAT3 phosphorylation. PER modulates Ang II/Ang 1-7 axis in Cd-intoxicated rats by decreasing Ang II expression and increasing Ang-(1-7) expression. PER inhibits Cd-induced apoptosis by lowering Bax, cytochrome c, and cleaved caspase 3 expressions while increasing Bcl-2 expression. In conclusion, PER dampens Cd-induced kidney intoxication by modulating Ang II/Ang 1-7 axis, suppressing NF-κB, JAK-1/STAT3, and apoptosis signals.

Boswellic acid and apigenin alleviate methotrexate-provoked renal and hippocampal alterations in rats: Targeting autophagy, NOD-2/NF-κB/NLRP3, and connexin-43

The neuronal and renal deteriorations observed in patients exposed to methotrexate (MTX) therapy highlight the need for medical interventions to counteract these complications. Boswellic acid (BA) and apigenin (APG) are natural phytochemicals with prominent neuronal and renal protective impacts in various ailments. However, their impacts on MTX-provoked renal and hippocampal toxicity have not been reported. Thus, the present work is tailored to clarify the ability of BA and APG to counteract MTX-provoked hippocampal and renal toxicity. BA (250 mg/kg) or APG (20 mg/kg) were administered orally in rats once a day for 10 days, while MTX (20 mg/kg, i.p.) was administered once on the sixth day of the study. At the histopathological level, BA and APG attenuated MTX-provoked renal and hippocampal aberrations. They also inhibited astrocyte activation, as proven by the inhibition of glial fibrillary acidic protein (GFAP). These impacts were partially mediated via the activation of autophagy flux, as proven by the increased expression of beclin1, LC3-II, and the curbing of p62 protein, alongside the regulation of the p-AMPK/mTOR nexus. In addition, BA and APG displayed anti-inflammatory features as verified by the damping of NOD-2 and p-NF-κB p65 to reduce TNF-α, IL-6, and NLRP3/IL-1β cue. These promising effects were accompanied with a notable reduction in one of the gap junction proteins, connexin-43 (Conx-43). These positive impacts endorse BA and APG as adjuvant modulators to control MTX-driven hippocampal and nephrotoxicity.

Role of Nrf2/HO-1, PPAR-γ, and cytoglobin signals in the pathogenesis of methotrexate-induced testicular intoxication in rats and the protective effect of diacerein

Methotrexate (MTX) is an inhibitor of folic acid reductase used in managing a variety of malignancies. Testicular injury by MTX is one of its serious adverse effects. The current investigation aims to assess the protective effects of diacerein (DIA) on testicular injury by MTX and clarify the possible underlying mechanisms. Testicular injury in rats was induced by a single injection of 20 mg/kg body weight of MTX. DIA was given in 25 mg/kg body weight/day and 50 mg/kg body weight/day doses for 10 days. Compared to the MTX group, DIA attenuated testicular intoxication as evidenced by improvement of testicular histopathological abnormalities and increased serum testosterone and luteinizing hormone. DIA attenuated testicular oxidative stress changes by lowering testicular MDA and boosting GSH content and SOD activity. Moreover, administration of DIA attenuated MTX-induced testicular inflammation, as proved by decreased TNF-α and IL-6. At the molecular level, DIA induced significant upregulation in Nrf2, HO-1, PPAR-γ, and cytoglobin protein expression. The present results proved that DIA, in a dose-dependent manner, exhibited notable amelioration of testicular toxicity induced by MTX through augmentation of anti-inflammatory and antioxidant effects combined by upregulating Nrf2/HO-1, PPAR-γ, and cytoglobin signaling.

Involvement of Nrf2-PPAR-γ signaling in Coenzyme Q10 protecting effect against methotrexate-induced testicular oxidative damage

Studies have identified Coenzyme Q10 (CoQ10) as a promising agent in improving idiopathic male infertility; however, its role in chemically or environmentally induced testicular dysfunction is not well-established. We investigated the potential of CoQ10 to attenuate methotrexate (MTX)-induced testicular damage and to identify molecular targets of CoQ10 effects. Wistar rats received a single intraperitoneal dose of 20 mg/kg MTX on the fifth day of the 10-day experimental protocol. 100 mg/kg CoQ10 was given orally daily for ten days, alone or combined with MTX. The testes of MTX-treated animals showed thickened tunica albuginea, distortion of seminiferous tubules with a marked reduction of germinal lining, a few primary spermatocytes with no spermatozoa, apoptotic cells, congested sub-capsular and interstitial blood vessels, and interstitial edema. Reduction of reproductive hormones and increased oxidative, inflammatory, and apoptotic biomarkers levels were also seen in the MTX-treated rats. CoQ10 + MTX-treated rats were protected against MTX-induced testicular histological changes and showed improvement in testosterone, luteinizing-, and follicle-stimulating hormone serum levels compared to the MTX group. The testes of the CoQ10 + MTX-treated rats showed reduced malondialdehyde, myloperoxidase, tumor necrosis factor -α, interleukin-6 and -1β and Bax: Bcl2 ratio and enhanced glutathione, and catalase compared to MTX alone. CoQ10 enhanced MTX-induced downregulation of Nrf2 and PPAR-γ signaling and modulated its downstream targets, the inducible nitric oxide synthase, NF-κB, Bax, and Bcl2. In conclusion, CoQ10 targeted the Nrf2-PPAR-γ signaling loop and its downstream pathways, mitigating MTX-induced oxidative stress-related damages and alleviating the testicular dysfunction MTX caused. Our data suggest Nrf2-PPAR-γ signaling as a potential therapeutic target in testicular toxicity, where oxidative stress, inflammation, and apoptosis trigger damage.

The enteroprotective effect of nifuroxazide against methotrexate-induced intestinal injury involves co-activation of PPAR-γ, SIRT1, Nrf2, and suppression of NF-κB and JAK1/STAT3 signals

Methotrexate (MTX) has long manifested therapeutic efficacy in several neoplastic and autoimmune disorders. However, MTX-associated intestinal toxicity restricts the continuation of treatment. Nifuroxazide (NIF) is an oral antibiotic approved for gastrointestinal infections as an effective antidiarrheal agent with a high safety profile. The current study was designed to explore the potential efficacy of NIF in alleviating intestinal toxicity associated with MTX chemotherapy with the elucidation of the proposed molecular mechanisms. Rats were administered NIF (50 mg/kg; p.o.) for ten days. On day five, a single i.p. injection of MTX (20 mg/kg) was given to induce intestinal intoxication. At the end of the experiment, duodenal tissue samples were isolated for biochemical, Western blotting, immunohistochemical (IHC), and histopathological analysis via H&E, PSA, and Alcian blue stains. NIF showed antioxidant enteroprotective effects against MTX intestinal intoxication through enhanced expression of the redox-sensitive signals of PPAR-γ, SIRT1, and Nrf2 estimated by IHC. Moreover, NIF down-regulated the pro-inflammatory cytokines (TNF-α, IL-1β, IL-6), NF-κB protein expression, and the phosphorylation of JAK1/STAT3 proteins, leading to mitigation of intestinal inflammation. In accordance, the histological investigation revealed that NIF ameliorated the intestinal pathological changes, preserved the goblet cells, and reduced the inflammatory cells infiltration. Therefore, NIF could be a promising candidate for adjunctive therapy with MTX to mitigate the associated intestinal injury and increase its tolerability.

Buspirone attenuated methotrexate-induced hippocampal toxicity in rats by regulating Nrf2/HO-1, PPAR-γ, NF-κB/nNOS, and ROS/NLRP3/caspase-1 signaling pathways

Methotrexate (MTX) is a chemotherapeutic agent widely used to treat a variety of tumors. Nonetheless, MTX-induced hippocampal neurotoxicity is a well-defined dose-limiting adverse effect that limits clinical utility. Proinflammatory cytokine production and oxidative stress are possible mechanisms for MTX-induced neurotoxicity. Buspirone (BSP), a partial agonist of the 5-HT1a receptor (5-HT1aR), has emerged as an anxiolytic drug. BSP has been shown to possess antioxidant and anti-inflammatory effects. The current study investigated BSP's potential anti-inflammatory and antioxidant effects in attenuating MTX-induced hippocampal toxicity. Rats received either BSP (1.5 mg/kg) orally for 10 days and MTX (20 mg/kg) i.p. on Day 5. BSP administration markedly protected hippocampal neurons from drastic degenerated neuronal changes induced by MTX. BSP significantly attenuated oxidative injury by downregulating Kelch-like ECH-associated protein 1 expression while potently elevating hippocampal Nrf2, heme oxygenase-1, and peroxisome proliferator-activated receptor expression. BSP dampened inflammation by reducing NO2 - , tumor necrosis factor-alpha, IL-6, and interleukin 1 beta levels mediated by downregulating NF-κB and neuronal nitric oxides synthase expression. Moreover, BSP potently counteracted hippocampal pyroptosis by downregulating NLRP3, ASC, and cleaved-caspase-1 proteins. Therefore, BSP may represent a promising approach to attenuate neurotoxicity in patients receiving MTX.

Umbelliferone potentiates intestinal protective effect of Lactobacillus Acidophilus against methotrexate-induced intestinal injury: Biochemical and histological study

Intestinal injury is a common adverse effect of methotrexate (MTX) therapy, limiting its clinical use. Despite oxidative stress and inflammation being the most embedded mechanism of injury, pharmacological agents that exhibit antioxidant and anti-inflammatory impacts could prevent such toxicities. This study aimed to assess the enteroprotective effect of lactobacillus acidophilus (LB) and/or umbelliferone (UMB) against MTX-induced intestinal injury. Histologically, pretreatment with LB, UMB, or their combinations preserve the intestinal histological structure and mucin content with superior effect in combination therapy. In addition, oral pretreatment with UMB, LB, or their combinations significantly restored oxidant/antioxidant status, as evidenced by the upregulation of Nrf2, SOD3, HO-1, GSH, and GST levels concurrent with a decline in MDA contents. Besides, they suppressed the inflammatory burden by inhibiting STAT3, MPO, TLR4, NF-κB, TNF-α, and IL-6 levels. Moreover, LB, UMB, or their combinations significantly upregulated Wnt and β-catenin expression. Notably, pretreatment with the combination therapy is superior to monotherapy in protecting rats' small intestines from MTX-induced enteritis. In conclusion, combined pretreatment with LB and UMB could be a novel therapeutic regimen for conditions of intestinal injury induced by MTX via restoring oxidant/antioxidant balance and suppressing inflammatory burden.