Toxicology Mechanisms and Methods最新文献

Colorectal cancer (CRC) poses a significant global health burden, being the third most prevalent cancer and the second most significant contributor to cancer-related deaths worldwide. Preventive strategies are crucial to combat this rising incidence. 6-shogaol, derived from ginger, has shown promise in preventing and treating various cancers. This study investigated the preventive effects of 6-shogaol on azoxymethane (AOM) and dextran sulfate sodium (DSS)-induced CRC in mice. Forty male BALB/c mice were randomly divided into control, 6-shogaol, AOM + DSS, and 6-shogaol + AOM + DSS. Mice in the control group received corn oil for 16 weeks, while those in the 6-Shogaol group were administered 20 mg/kg of 6-shogaol for 16 weeks. The AOM + DSS group received a single intraperitoneal dose (ip) of 10 mg/kg of AOM, followed by three cycles of 2.5% DSS in drinking water. The 6-shogaol + AOM + DSS group received both 6-shogaol for 16 weeks and a single ip of 10 mg/kg of AOM, followed by three cycles of 2.5% DSS in drinking water. The AOM + DSS-treated mice exhibited reduced food consumption, colon weight, and colon length, along with increased tumor formation. Co-administration of 6-shogaol effectively reversed these changes, inhibiting CRC development. Histopathological analysis revealed protective effects of 6-shogaol against colonic insults and modulation of inflammatory responses. 6-shogaol significantly reduced Carcinoembryonic antigen and Kiel 67 levels, indicating inhibition of tumor cell proliferation. Mechanistically, 6-shogaol promoted apoptosis by upregulating protein 53 and caspase-3 expression, and it effectively restored the balance of the Wingless-related integration site signaling pathway by regulating β-catenin and adenomatous polyposis coli levels. Moreover, 6-shogaol demonstrated anti-inflammatory effects, reducing myeloperoxidase, Tumor necrosis factor alpha, and cyclooxygenase-2 levels in AOM/DSS-treated mice. Additionally, 6-shogaol restored redox homeostasis by reducing lipid peroxidation and nitrosative stress and enhancing antioxidant enzyme activities. The findings suggest that 6-shogaol inhibits cell proliferation, induces apoptosis, regulates Wnt signaling, suppresses inflammation, and restores redox homeostasis, providing comprehensive insights into its potential therapeutic benefits for CRC.

Leflunomide (LFND) is an immunosuppressive and immunomodulatory disease-modifying antirheumatic drug (DMARD) that was approved for treating rheumatoid arthritis. LFND-induced cardiotoxicity was not fully investigated since its approval. We investigated the cardiac injury in male mice and identified the role of nuclear factor erythroid 2-related factor 2/nuclear factor-κ B (Nrf2/NF-κB) signaling. Male albino mice were assigned into five groups as control, vehicle, and LFND (2.5, 5, and 10 mg/kg). We investigated cardiac enzymes, histopathology, and the mRNA expression of Nrf2, NF-κB, BAX, and tumor necrosis factor-α (TNF-α). The bioinformatic study identified the interaction between LFND and Nrf2/NF-κB signaling; this was confirmed by amelioration in mRNA expression (0.5- to 0.34-fold decrease in Nrf2 and 2.6- to 4.61-fold increases in NF-κB genes) and increased (1.76- and 2.625-fold) serum creatine kinase (CK) and 1.38- and 2.33-fold increases in creatine kinase-MB (CK-MB). Histopathological results confirmed the dose-dependent effects of LFND on cardiac muscle structure in the form of cytoplasmic, nuclear, and vascular changes in addition to increased collagen deposits and apoptosis which were increased compared to controls especially with LFND 10 mg/kg. The current study elicits the dose-dependent cardiac injury induced by LFND administration and highlights, for the first time, dysregulation in Nrf2/NF-κB signaling.

Objectives: This study explored the mitigating properties of hyperin (HYP) on renotoxicity induced by cadmium chloride (CdCl₂).

Methods: Four groups of seven male albino mice each were used in this experiment. Group 1 served as the control, receiving no treatment. Group 2 received daily oral gavage of CdCl₂ at 0.3 mg/kg body weight for 28 d. Group 3 received both CdCl₂ (0.3 mg/kg) and HYP (100 mg/kg) daily using the same administration method. Finally, Group 4 received only HYP (100 mg/kg) daily.

Results: Cd exposure significantly increased kidney dysfunction markers (blood urea nitrogen and creatinine) and oxidative stress (reactive oxygen species [ROS] and malondialdehyde [MDA]). Conversely, it decreased antioxidant enzyme activities (glutathione peroxidase (GPx] and catalase [CAT]) and glutathione (GSH) levels. Nuclear factor erythroid 2-related factor 2 (Nrf-2) and antioxidant gene expression decreased, while Kelch-like ECH-associated protein 1 expression increased. Additionally, Cd exposure increased inflammatory mediators (nuclear factor kappa B, tumor necrosis factor alpha [TNF-α], interleukin-1β [IL-1β], and cyclooxygenase-2) and apoptotic markers (Bax and caspase-3), alongside decreased Bcl-2 expression and renal tissue abnormalities. Mitochondrial dysfunction manifested with diminished activities of Krebs cycle and respiratory chain enzymes, and reduced mitochondrial membrane potential. Co-treatment with HYP significantly attenuated these detrimental effects through its anti-apoptotic, antioxidant, and anti-inflammatory properties.

Conclusion: HYP co-treatment significantly attenuated CdCl₂-induced renal damage in mice, suggesting its potential as a protective agent against Cd-induced kidney toxicity.

Invasive fungal aspergillosis is a leading cause of morbidity and mortality in many species including avian species such as common ravens (Corvus corax). Methods were developed for mass spectral determination of voriconazole in raven plasma as a means of determining pharmacokinetics of this antifungal agent. Without further development, GC/MS/MS (gas chromatography-tandem quadrupole mass spectrometry) proved to be inferior to LC/MS/MS (liquid chromatography-tandem quadrupole mass spectrometry) for measurement of voriconazole levels in treated raven plasma owing to numerous heat-induced breakdown products despite protection of voriconazole functional groups with trimethylsilyl moieties. LC/MS/MS measurement revealed in multi-dosing experiments that the ravens were capable of rapid or ultrarapid metabolism of voriconazole. This accounted for the animals' inability to raise the drug into the therapeutic range regardless of dosing regimen unless cytochrome P450 (CYP) inhibitors were included. Strategic selection of CYP inhibitors showed that of four selected compounds including cimetidine, enrofloxacin and omeprazole, only ciprofloxacin (Cipro) was able to maintain voriconazole levels in the therapeutic range until the end of the dosing period. The optimal method of administration involved maintenance doses of voriconazole at 6 mg/kg and ciprofloxacin at 20 mg/kg. Higher doses of voriconazole such as 18 mg/kg were also tenable without apparent induction of toxicity. Although most species employ CYP2C19 to metabolize voriconazole, it was necessary to speculate that voriconazole might be subject to metabolism by CYP1A2 in the ravens to explain the utility of ciprofloxacin, a previously unknown enzymatic route. Finally, despite its widespread catalog of CYP inhibitions including CYP1A2 and CYP2C19, cimetidine may be inadequate at enhancing voriconazole levels owing to its known effects on raising gastric pH, a result that may limit voriconazole solubility.

The agricultural fumigant pesticide aluminum phosphide (AlP) is cardiotoxic. Water causes AlP to emit phosphine gas, a cardiac toxin that affects heart function and causes cardiogenic shock. AlP poisoning's high fatality rate is due to cardiotoxicity. This study examines how resveratrol reduces oxidative stress, mitochondrial activity, and apoptosis in human cardiac myocyte (HCM) cells. After determining the optimal doses of resveratrol using the MTT test, HCM cells were subjected to a 24-h treatment of resveratrol following exposure to AlP (2.36 μM). The levels of reactive oxygen species (ROS), superoxide dismutase (SOD) activity, mitochondrial swelling, mitochondrial cytochrome c release, and mitochondrial membrane potential (MMP) in HCM cells were investigated. Also, the expression of Bax and Bcl-2, caspace-3 activity, and apoptosis were assessed. The present investigation revealed that AlP substantially increased the level of ROS and decreased SOD activation, which were significantly modulated by resveratrol in a dose-dependent manner. Moreover, AlP induced an elevation of mitochondrial swelling, cytochrome c release, and MMP collapse. Co-administration of resveratrol significantly reduced above mitochondrial markers. AlP also significantly upregulated BAX and downregulated Bcl-2 expression, elevated caspace-3 activity, and apoptosis. Resveratrol co-administration was able to meaningfully modulate the mentioned parameters and finally reduce apoptosis. In conclusion, resveratrol, via its pleotropic properties, significantly demonstrated cytoprotective effects on HCM cytotoxicity induced by AlP.

This study focuses on the comparative metabolic profiling and effects of two steroid types: natural and synthetic, specifically 17α-methyl testosterone (17α-MT) at varying concentrations (1.5, 2, and 3 mg/kg) in rainbow trout (Oncorhynchus mykiss). Over a 75-day feeding trial, growth metrics, such as feed efficiency, daily specific growth, live weight gain, total weight gain, and survival rate were systematically monitored every 15 days. At the end of the feeding trial, histopathology, immunohistochemistry, and metabolome analyses were performed in the high-concentration groups (3 mg/kg natural and 3 mg/kg synthetic), in which the lowest survival rate was determined. Key findings reveal that the type of hormone significantly influences growth parameters. While some natural steroids enhanced certain growth aspects, synthetic variants often yielded better results. The metabolomic analysis highlighted significant shifts in the metabolism of tryptophan, purine, folate, primary bile acids, phosphonates, phosphinates, and xenobiotics via cytochrome P450 pathways. Histopathologically, the natural hormone groups showed similar testicular, hepatic, muscular, gill, cerebral, renal, and intestinal tissue structures to the control, with minor DNA damage and apoptosis observed through immunohistochemistry. Conversely, the synthetic hormone groups exhibited moderate DNA damage and mild degenerative and necrotic changes in histopathology.

Aluminum (Al) overexposure damages various organ systems, especially the nervous system. Regularly administered aluminum chloride (AlCl₃) to rats causes dementia and pathophysiological alterations linked to Alzheimer's disease (AD). Taxifolin's neuroprotective effects against AlCl₃-induced neurotoxicity in vitro and in vivo studies were studied. Taxifolin (0.1, 0.3, 1, 3, and 10 μM) was tested against AlCl₃ (5 mM)-induced neurotoxicity in C6 and SH-SY5Y cells using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) and lactate dehydrogenase (LDH) assays. Additionally, neural morphology was examined by confocal microscopy. Additionally, taxifolin's mode of binding with the co-receptor of toll-like receptor 4 (TLR4), human myeloid differentiation-2 (hMD-2) was investigated. AlCl₃ (25 mg/kg/d, i.p.) was administered to rats for 14 d, and from the eighth day, taxifolin (1, 2, and 5 mg/kg/d, i.p.) was given along with AlCl₃. This study assessed memory impairment using the Morris water maze, plus maze, and pole tests. This study also performed measurement of oxidant (malondialdehyde [MDA] and nitrite), antioxidant (reduced glutathione), and inflammatory (myeloperoxidase [MPO] activity, TLR4 expression) parameters in rats' brain in addition to histopathology. The docking score for taxifolin with hMD-2 was found to be -4.38 kcal/mol. Taxifolin treatment reduced the neurotoxicity brought on by AlCl₃ in both C6 and SH-SY5Y cells. Treatment with 10 μM taxifolin restored AlCl₃-induced altered cell morphology. AlCl₃ administration caused memory loss, oxidative stress, inflammation (increased MPO activity and TLR4 expression), and brain atrophy. Taxifolin treatment significantly improved the AlCl₃-induced memory impairment. Taxifolin treatment also mitigated the histopathological and neurochemical consequences of repeated AlCl₃ administration in rats. Thus, taxifolin may protect the brain against AD.

Recent studies have revealed a notable connection between pesticide exposure and Recurrent Pregnancy Loss (RPL), yet the precise molecular underpinning of this toxicity remains elusive. Through the alignment of Differentially Expressed Genes (DEGs) of healthy and RPL patients with the target genes of 9 pesticide components, we identified a set of 12 genes responsible for RPL etiology. Interestingly, biological process showed that besides RPL, those 12 genes also associated with preeclampsia and cardiovascular disease. Enrichment analysis showed the engagement of these genes associated with essential roles in the molecular transport of small molecules, as well as the aldosterone-regulated sodium reabsorption, endocrine and other factor-regulated calcium reabsorption, mineral absorption, ion homeostasis, and ion transport by P-type ATPases. Notably, the crosstalk targets between pesticide components played crucial roles in influencing RPL results, suggesting a role in attenuating pesticide agents that contribute to RPL. It is important to note that non-significant concentration of the pesticide components observed in both control and RPL samples should not prematurely undermine the potential for pesticides to induce RPL in humans. This study emphasizes the complexity of pesticide induced RPL and highlights avenues for further research and precautionary measures.

The modulatory role of primrose oil (PO) supplementation enriched with γ-linolenic acid and D/L-alpha tocopherol acetate against a carbon tetrachloride (CCl₄)-induced liver damage model was assessed in this study. Twenty male Albino rats were divided into four groups. The control group received corn oil orally. The PO group received 10 mg/kg P O orally. The CCl₄ group received 2 mL/kg CCl₄ orally and PO/CCl₄ group; received PO and 2 mL/kg CCl₄ orally. The relative liver weight was recorded. Serum liver enzymes, hepatic malondialdehyde (MDA), hepatic reduced glutathione (GSH) and the expression of hepatic tumor necrosis factor-alpha (TNF-α), interleukin 1 beta (IL-1β), and interleukin 6 (IL-6) were assessed. The binding affinities of γ-linolenic acid and D/L-alpha tocopherol constituents with IL-1β, IL-6 and TNF-α were investigated using molecular docking simulations. Histopathological and electron microscopic examinations of the liver were performed. The results indicated that CCl₄ elevated serum liver enzyme and hepatic MDA levels, whereas GSH levels were diminished. The upregulation of IL-1β, IL-6, and TNF-α gene expressions were induced by CCl₄ treatment. The PO/CCl4-treated group showed amelioration of hepatic injury biomarkers and oxidative stress. Restoration of histopathological and ultrastructural alterations while downregulations the gene expressions of TNF-α, IL1-β and IL-6 were observed. In conclusion, evening primrose oil enriched with γ-linolenic acid and D/L-alpha tocopherol acetate elicited a potential amelioration of CCl₄-induced hepatic toxicity.