Lipopolysaccharide Exacerbates Ketamine-Induced Psychotic-Like Behavior, Oxidative Stress, and Neuroinflammation in Mice: Ameliorative Effect of Diosmin

Dissecting the antidepressant effect of troxerutin: modulation of neuroinflammatory and oxidative stress biomarkers in lipopolysaccharide-treated mice

The role of neuroinflammation in the pathogenesis of depression has prompted the search for new antidepressants. Troxerutin, a bioflavonoid with anti-inflammatory and antioxidant properties, has shown promise, but its impact on neurobehavioral functions remains poorly understood. This study aimed to investigate the antidepressant potential of troxerutin and its effect on the neuroinflammatory response. Here, we exposed male Swiss mice (n = 5/group) to various treatments, including naive and negative controls receiving distilled water, troxerutin-treated groups administered at different doses (10, 20, 40 mg/kg, i.p.), and an imipramine-treated group (25 mg/kg, i.p.). After seven days of treatment, with the exception of the naive group, mice were administered a single dose of lipopolysaccharide (LPS, 0.83 mg/kg). Behavioral evaluations, consisting of the novelty-suppressed feeding (NSF) test, forced swim test (FST), and open field test (OFT), were conducted. Additionally, brain samples were collected for biochemical and immunohistochemical analyses. Troxerutin significantly reduced immobility time in the FST and mitigated behavioral deficits in the NSF test. Additionally, troxerutin increased glutathione (GSH) and superoxide dismutase (SOD) levels while reducing nitrite, malondialdehyde (MDA), tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and interferon-gamma (IFN-γ) levels compared to the negative control. Immunohistochemistry analysis revealed decreased expression of inducible nitric oxide synthase (iNOS) and nuclear factor-kappa B (NF-κB) in troxerutin-treated mice. Overall, these findings suggest that troxerutin exerts significant antidepressive-like effects, likely mediated by its anti-inflammatory and antioxidant mechanisms. The reduction in neuroinflammatory and oxidative stress biomarkers, along with the improvement in behavioral outcomes, underscores troxerutin's potential as a therapeutic agent for depression.

Antipsychotic effect of diosgenin in ketamine-induced murine model of schizophrenia: Involvement of oxidative stress and cholinergic transmission

A decrease in the levels of antioxidant arsenals exacerbate generation of reactive oxygen/nitrogen species, leading to neurochemical dysfunction, with significant impact on the pathogenesis of psychotic disorders such as schizophrenia. This study examined the preventive and reversal effects of diosgenin, a phyto-steroidal saponin with antioxidant functions in mice treated with ketamine which closely replicates schizophrenia-like symptoms in human and laboratory animals. In the preventive phase, adult mice cohorts were clustered into 5 groups (n = 9). Groups 1 and 2 received saline (10 mL/kg, i.p.), groups 3 and 4 were pretreated with diosgenin (25 and 50 mg/kg), and group 5 received risperidone (0.5 mg/kg) orally for 14 days. Mice in groups 2-5 additionally received a daily dose of ketamine (20 mg/kg, i.p.) or saline (10 mL/kg/day, i.p.). In the reversal phase, mice received intraperitoneal injection of ketamine or saline for 14 consecutive days prior to diosgenin (25 and 50 mg/kg/p.o./day) and risperidone (0.5 mg/kg/p.o./day) treatment from days 8-14. Mice were assessed for behavioral changes. Oxidative, nitrergic markers, and cholinergic (acetylcholinesterase activity) transmission were examined in the striatum, prefrontal-cortex and hippocampus. Diosgenin prevented and reversed hyperlocomotion, cognitive and social deficits in mice treated with ketamine relative to ketamine groups. The increased acetylcholinesterase, malondialdehyde and nitrite levels produced by ketamine were reduced by diosgenin in the striatum, prefrontal-cortex and hippocampus, but did not reverse striatal nitrite level. Diosgenin increased glutathione, and catalase levels, except for hippocampal catalase activity when compared with ketamine controls. Conclusively, these biochemical changes might be related to the behavioral deficits in ketamine-treated mice, which were prevented and reversed by diosgenin.

Epigallocatechin-gallate attenuates rapamycin exacerbated high fat diet-induced autophagy, hormonal dysregulation, testicular and brain oxidative stress, and neurochemical changes in rats

This study investigated whether epigallocatechin-gallate (EGCG) could counteract the detrimental effects of high-fat diet (HFD)-induced obesity in rats exposed to rapamycin-induced reproductive and neuronal changes. Six rats per treatment group (n = 6) were utilized, in which groups 1 and 2 had dimethylsulfoxide (DMSO) (0.1%) and EGCG (80 mg/kg) respectively. Group 3 received HFD + 0.1% DMSO daily for 56 days. Group 4 received HFD + rapamycin (1 mg/kg) orally for 56 days. Rats in group 5 received HFD for 56 days and EGCG (80 mg/kg, p.o.) from days 29-56. Group 6 received the combination of HFD + rapamycin (56 days) with EGCG (80 mg/kg) from days 29-56. Cognitive loss was assessed using Y-maze-test (YMT). Afterwards, serum sex hormones, insulin-glucose balance, serotonin concentration, acetylcholinesterase activity, sperm features, antioxidants, and the markers of oxido-nitrergic, autophagy and apoptotic mediators were assessed. EGCG reversed rapamycin exacerbated HFD-induced alterations in spermatogenesis, insulin-glucose balance, reproductive hormones, oxido-nitrergic stress, and altered serotonin, acetylcholinesterase levels, and autophagic and apoptotic activities in rats' testes and brains respectively. EGCG significantly attenuated HFD-induced cognitive loss. The study showed that EGCG attenuated rapamycin-mediated HFD-induced spermatogenesis deficiency and cognitive impairment via normalization of reproductive hormones, testicular and brain oxidative stress, apoptotic, autophagic activities, with serotonin and cholinergic levels in rats.