Edaravone protects from memory impairment induced by chronic L-methionine administration

Edaravone's reno-protective effects against chronic heat-stress exposure

Edaravone (EDV) is a potent antioxidant with anti-inflammatory properties. It is used to treat various diseases, especially neurodegenerative diseases. This study aims to examine EDV's potential renal protective effects on kidney injury induced by heat stress in rats. Male Wistar rats were segregated into four distinct groups (n = 16/group): control (Ctr), heat stress (HS), edaravone (EDV), and HS+EDV groups. Heat stress was applied 6 days a week for 30 min for 8 weeks, and EDV treatment (6 mg/kg. IP) was administered simultaneously in the HS+EDV group. After the experiment, blood and kidney tissue samples were gathered for subsequent analysis. Compared to the control group, the HS group exhibited a significant increase in serum creatinine and urea levels (P < 0.05). Additionally, malondialdehyde level and catalase activity, tumor necrosis factor-α (TNF-α), and interleukin-1 beta (IL-1β) mRNA expression were increased in the kidney tissue during HS. The renal tissues of the heat-stressed animal showed noticeable histological alterations compared to the control group. However, in the HS+EDV and EDV groups, the creatinine and urea concentrations in the blood were markedly reduced compared to the HS group (P < 0.05). In addition, renal oxidative stress biomarkers were normalized (malondialdehyde levels and catalase activity; P < 0.05). The histopathological alterations in the renal tissues of the groups treated with EDV were markedly diminished. In addition, the renal mRNA expression levels of IL-1β and TNF-α were markedly reduced in the HS+EDV group compared to the HS group (P < 0.05). EDV treatment in a heat-stress rat model demonstrated a protective effect on renal tissue, most likely due to its antioxidant and anti-inflammatory properties.

In silico docking, ADMET profiling, and bio-accessibility experimentation on Breynia retusa phytocompounds and in vitro validation for anti-proliferative potencies against ovarian carcinoma

This study aimed to assess the medicinal properties of Breynia retusa, a plant rich in phytocompounds predominantly used as an ethnomedicinal agent in Western Ghats, which appeared to be promising for therapeutic use, especially in the treatment of ovarian cancer. Herein, its cytotoxic potential on ovarian cancer cell lines SKOV-3, neurotoxicity, antioxidant activity, and molecular docking was determined to aid in explaining the mechanisms of interactions with proteins related to ovarian cancer. B . retusa methanolic extract demonstrated exuberant antioxidant activity, with 81.91% scavenging ability of DPPH radicals and efficient reduction of phosphomolybdenum (22.98 mg ascorbic acid equivalents antioxidant capacity/g extract). The extract proved to be an important anti-inflammatory agent through membrane stabilization inhibition of 83%. The cytotoxicity study against the SKOV-3 cell line indicated an IC50 value of 34.01 µg/mL and a very negligible neurotoxicity in SH-SY5Y cell lines. The GC-MS and HPLC profiling indicated many anticancer compounds in the extract such as secalciferol, methyl gallate, ricinoleic acid, gallic acid, and naringenin. The docking study showed significant interactions of secalciferol molecules with the key ovarian cancer proteins, which include IGF1 (-6.758 kcal/mol) and c-ERBB2 (-4.281 kcal/mol). Fatty acid derivatives and methyl gallate showed efficient dock scores (< -5.0 kcal/mol) with antioxidant (catalase and superoxide dismutase) enzymes and inflammatory cytokines (IL-6 and COX-1), respectively, as evidences of antioxidant and anti-inflammatory potentials. The bio-accessibility of phenolics and their antioxidant activity ranged above 90%, indicating the promising bioavailability of phytochemicals expected in vivo. Hence the current study emphasizes the anticancer potential of B. retusa phytocompounds that appeared to interact very strongly with ovarian cancer targets and confirms the dose-dependent cytotoxic and antioxidant activities of B. retusa methanolic extract.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13205-025-04276-8.

Edaravone protects against cuprizone-induced demyelination in rats by modulating TNF-α/NF-ĸB/NLRP3 signaling and the kynurenine pathway

Multiple sclerosis (MS) is a neurodegenerative disorder involving various pathways that affect disease progression and treatment. The kynurenine pathway (KP) has gained attention in MS studies, contributing to demyelination and disease progression. This study aimed to explore the pharmacological effects of edaravone (EDV) on the corpus callosum and the spinal cord in the cuprizone (CPZ) animal model of demyelination. Male Wistar rats were randomly divided into the control, CPZ, and CPZ-EDV groups. CPZ (500 mg/kg/day) was administered via oral gavage for eight weeks, and at the start of the 5th week, EDV (5 mg/kg/day,I.P.) was initiated and continued for 4 weeks. EDV ameliorated behavioral and motor deficits in CPZ-intoxicated rats and promoted the differentiation of oligodendrocyte progenitor cells by activating OLIG2, enhancing re-myelination. This was demonstrated by increased density of myelinated nerve fibers and OLIG2+ cells co-expressing myelin basic protein (MBP), indicating enhanced OPC differentiation and remyelination. EDV also reduced the inflammatory mediators TNF-α and NF-ĸB, and diminished the activation of NLRP3 inflammasome, inhibiting the release of IL-1β. Furthermore, EDV decreased indoleamine 2,3-dioxygenase-1 (IDO1) mRNA expression and activity, as well as the protein levels of kynurenine 3-monooxygenase (KMO), leading to reduced neurotoxic metabolites (quinolinic and anthranilic acid) while elevating the neuroprotective metabolite kynurenic acid (KYNA). In conclusion, EDV exerted neuroprotective effects by reducing inflammation, inhibiting the KP's neurotoxic metabolites, and promoting remyelination through OLIG2 activation. These effects are possibly attributed to EDV's action on TNF-α/NF-ĸB/NLRP3 signaling and the KP.

Pentoxifylline protects memory performance in streptozotocin-induced diabetic rats

Diabetes, characterized by elevated blood glucose levels and associated organ damage, is reportedly correlated with adecline in cognitive functions with a potential involvement of oxidative stress mechanisms. Mitochondria-induced oxidative stress reported to cause hyperglycemia is believed to impair hippocampal neural plasticity, affecting long-term potentiation, and isconsidered crucial for maintaining memory functions. In this study, the neuroprotective effect of Pentoxifylline (PTX) for four weeks, an agent known for antioxidant and anti-inflammatory properties, was examined in an animal model of diabetes. In a streptozotocin (STZ) diabetic model, rats received intraperitoneal PTX (100 mg/kg), and learning and memory functions were tested using the radial arm water maze. STZ-treated diabetic rats exhibited impaired learning and memory functions (short/long-term, P < 0.05), whereas PTX treatment prevented these deficits. PTX treatment normalized diabetes-induced reduction in the protein expression levels of two enzymes of antioxidant defense superoxide dismutase and glutathione peroxidase (P < 0.05) in the hippocampal brain tissues. PTX treatment also mitigated STZ-induced increase in lipid peroxidation (TBARS, P < 0.05). Furthermore, reduced/oxidized glutathione (GSH/GSSG) ratios were enhanced in PTX-treated diabetic rats (P < 0.05), emphasizing the importance of redox balance restoration. However, PTX treatment did not significantly affect theantioxidant defense enzyme catalase activity. In conclusion, STZ-induced diabetes resulted in learning and memory impairment in rats, while PTX treatment prevented these effects, most likely via enhancement of antioxidant defense in the brain. This study highlights PTX's potential neuroprotective benefits, providing translational insights into the issue of diabetes-related cognitive complications.

Development of Atomoxetine-Loaded NLC In Situ Gel for Nose-to-Brain Delivery: Optimization, In Vitro, and Preclinical Evaluation

The present study investigates the brain-targeted efficiency of atomoxetine (AXT)-loaded nanostructured lipid carrier (NLC)-laden thermosensitive in situ gel after intranasal administration. AXT-NLC was prepared by the melt emulsification ultrasonication method and optimized using the Box-Behnken design (BBD). The optimized formulation (AXT-NLC) exhibited particle size PDI, zeta potential, and entrapment efficiency (EE) of 108 nm, 0.271, -42.3 mV, and 84.12%, respectively. The morphology of AXT-NLC was found to be spherical, as confirmed by SEM analysis. DSC results displayed that the AXT was encapsulated within the NLC matrix. Further, optimized NLC (AXT-NLC13) was incorporated into a thermosensitive in situ gel using poloxamer 407 and carbopol gelling agent and evaluated for different parameters. The optimized in situ gel (AXT-NLC13G4) formulation showed excellent viscosity (2532 ± 18 Cps) at 37 °C and formed the gel at 28-34 °C. AXT-NLC13-G4 showed a sustained release of AXT (92.89 ± 3.98% in 12 h) compared to pure AXT (95.47 ± 2.76% in 4 h). The permeation flux through goat nasal mucosa of AXT from pure AXT and AXT-NLC13-G4 was 504.37 µg/cm²·h and 232.41 µg/cm²·h, respectively. AXT-NLC13-G4 intranasally displayed significantly higher absolute bioavailability of AXT (1.59-fold higher) than intravenous administration. AXT-NLC13-G4 intranasally showed 51.91% higher BTP than pure AXT (28.64%) when administered via the same route (intranasally). AXT-NLC13-G4 showed significantly higher BTE (207.92%) than pure AXT (140.14%) when administered intranasally, confirming that a high amount of the AXT reached the brain. With the disrupted performance induced by L-methionine, the AXT-NLC13-G4 showed significantly (p < 0.05) better activity than pure AXT as well as donepezil (standard). The finding concluded that NLC in situ gel is a novel carrier of AXT for improvement of brain delivery by the intranasal route and requires further investigation for more justification.

Epigenetic Mechanisms Involved in the Effects of Maternal Hyperhomocysteinemia on the Functional State of Placenta and Nervous System Plasticity in the Offspring

According to modern view, susceptibility to diseases, specifically to cognitive and neuropsychiatric disorders, can form during embryonic development. Adverse factors affecting mother during the pregnancy increase the risk of developing pathologies. Despite the association between elevated maternal blood homocysteine (Hcy) and fetal brain impairments, as well as cognitive deficits in the offspring, the role of brain plasticity in the development of these pathologies remains poorly studied. Here, we review the data on the negative impact of hyperhomocysteinemia (HHcy) on the neural plasticity, in particular, its possible influence on the offspring brain plasticity through epigenetic mechanisms, such as changes in intracellular methylation potential, activity of DNA methyltransferases, DNA methylation, histone modifications, and microRNA expression in brain cells. Since placenta plays a key role in the transport of nutrients and transmission of signals from mother to fetus, its dysfunction due to aberrant epigenetic regulation can affect the development of fetal CNS. The review also presents the data on the impact of maternal HHcy on the epigenetic regulation in the placenta. The data presented in the review are not only interesting from purely scientific point of view, but can help in understanding the role of HHcy and epigenetic mechanisms in the pathogenesis of diseases, such as pregnancy pathologies resulting in the delayed development of fetal brain, cognitive impairments in the offspring during childhood, and neuropsychiatric and neurodegenerative disorders later in life, as well as in the search for approaches for their prevention using neuroprotectors.

Exploring the effects of edaravone in rats with contrast-induced acute kidney injury

AIMS

Oxidative stress and inflammatory response play a vital role in the pathogenesis of contrast-induced acute kidney injury (CI-AKI). This study investigated the effects of edaravone in rats with CI-AKI.

MAIN METHODS

Male Sprague Dawley rats were randomly assigned into four groups (n = 11-14/group): control, edaravone (30 mg/kg/day intraperitoneally (IP)), CI-AKI, and edaravone with CI-AKI. The induction of CI-AKI was performed by dehydration and the administration of contrast media (iohexol) and inhibitors of prostaglandin (indomethacin) and nitric oxide synthesis (L-NAME: N-nitro L-arginine methyl ester). Edaravone was administered for two weeks before the induction of CI-AKI. Serum creatinine and urea, renal oxidative stress and inflammatory biomarkers, and histopathological alterations were evaluated after 48 h of contrast exposure.

KEY FINDINGS

Rats with CI-AKI showed a significant increase in serum creatinine and urea. The levels of antioxidant biomarkers including glutathione peroxidase, superoxide dismutase and reduced glutathione were significantly decreased in CI-AKI group versus control. Pre-treatment of rats with edaravone normalized kidney function and protected the kidney from oxidative damage as demonstrated by normalization of previous biomarkers. Furthermore, edaravone partially ameliorated renal histopathological alterations relative to the CI-AKI group, notably in the nephrons. No changes were observed in inflammatory biomarkers including tumour necrosis factor-alpha and interleukin-6 among all groups.

SIGNIFICANCE

The current findings suggest that edaravone could be a potential strategy to ameliorate developing CI-AKI possibly by improving renal antioxidant capacity. Further studies are warranted to expand the current understanding of the use of edaravone in the various models of AKI.

Sitagliptin Attenuates the Cognitive Deficits in L-Methionine-Induced Vascular Dementia in Rats

Vascular dementia (VaD) is the second most prevalent type of dementia characterized by progressive cognitive deficits and is a major risk factor for the development of Alzheimer's disease and other neurodegenerative disorders. This study is aimed at determining the potential neuroprotective effect of sitagliptin (STG) on cognitive deficits in L-methionine-induced VaD in rats and the possible underlying mechanisms. 30 adult male Wistar albino rats were divided equally (n = 10) into three groups: control, VaD, and VaD + STG groups. The cognitive performance of the animals was conducted by open field, elevated plus maze, Y-maze, novel object recognition, and Morris water maze tests. Serum homocysteine, TNF-α, IL-6, IL-10, total cholesterol, and triglycerides levels were assessed together with hippocampal MDA, SOD, and BDNF. Histopathological and immunohistochemical assessments of the thoracic aorta and hippocampus (CA1 region) were also performed. Chronic L-methionine administration impaired memory and learning and induced anxiety. On the other hand, STG protected against cognitive deficits through improving oxidative stress biomarkers, inflammatory mediators, lipid profiles, and hippocampus level of BDNF as well as decreasing caspase-3 and GFAP and increasing Ki-67 immunoreactions in the hippocampus. Also, STG improved the endothelial dysfunction via upregulation of aortic eNOS immunoreaction. STG improved the cognitive deficits of L-methionine-induced VaD by its antioxidant, anti-inflammatory, antiapoptotic, and neurotrophic effects. These findings suggest that STG may be a promising future agent for protection against VaD.

Methionine as a double-edged sword in health and disease: Current perspective and future challenges

Methionine is one of the essential amino acids and plays a vital role in various cellular processes. Reports advocate that methionine restriction and supplementation provide promising outcomes, and its regulation is critical for maintaining a healthy life. Dietary methionine restriction in houseflies and rodents has been proven to extend lifespan. Contrary to these findings, long-term dietary restriction of methionine leads to adverse events such as bone-related disorders, stunted growth, and hyperhomocysteinemia. Conversely, dietary supplementation of methionine improves hepatic steatosis, insulin resistance, inflammation, fibrosis, and bone health. However, a high level of methionine intake shows adverse effects such as hyperhomocysteinemia, reduced body weight, and increased cholesterol levels. Therefore, dietary methionine in a safe dose could have medicinal values. Hence, this review is aimed to provide a snapshot of the dietary role and regulation of methionine in the modulation of health and age-related diseases.

Hyperhomocysteinemia: Metabolic Role and Animal Studies with a Focus on Cognitive Performance and Decline-A Review

Disturbances in the one-carbon metabolism are often indicated by altered levels of the endogenous amino acid homocysteine (HCys), which is additionally discussed to causally contribute to diverse pathologies. In the first part of the present review, we profoundly and critically discuss the metabolic role and pathomechanisms of HCys, as well as its potential impact on different human disorders. The use of adequate animal models can aid in unravelling the complex pathological processes underlying the role of hyperhomocysteinemia (HHCys). Therefore, in the second part, we systematically searched PubMed/Medline for animal studies regarding HHCys and focused on the potential impact on cognitive performance and decline. The majority of reviewed studies reported a significant effect of HHCys on the investigated behavioral outcomes. Despite of persistent controversial discussions about equivocal findings, especially in clinical studies, the present evaluation of preclinical evidence indicates a causal link between HHCys and cognition-related- especially dementia-like disorders, and points out the further urge for large-scale, well-designed clinical studies in order to elucidate the normalization of HCys levels as a potential preventative or therapeutic approach in human pathologies.

Every-other day fasting prevents memory impairment induced by high fat-diet: Role of oxidative stress

Imbalance of diet consumption results in memory and learning deterioration. High-fat diet (HFD) causes neuronal damage and eventually cognitive impairment, which can be related to increasing oxidative stress in the brain. Using the every other day fasting (EODF) paradigm, as a method of dietary restriction is thought to provide protection of learning and memory in several experimental studies. In the current work, the preventive effect of EODF paradigm on memory impairment-induced by HFD was investigated. Adult male Wistar rats were fed with HFD using the EODF paradigm for six weeks. At the end of these six weeks, and while the previous treatment were continued, rats were examined for learning and memory (both the short-term and the long-term memory) using the radial arm water maze (RAWM). Oxidative stress in the brain, namely in the hippocampus was also assessed. Chronic administration of HFD induced impairment in both, short- and long- term memory that was prevented using EODF paradigm. Furthermore, EODF prevented HFD-induced decrease in the activities of the antioxidant enzymes, SOD and catalase along with reduction of glutathione (GSH) level and the ratio of reduced glutathione/oxidized glutathione (GSH/GSSG ratio). The EODF also inhibited rise in oxidized glutathione (GSSG) and thiobarbituric acid reactive substances (TBARS) seen with HFD. In conclusion, EODF ameliorated oxidative stress and memory impairment induced by chronic HFD. This probably, can be explained by the ability of EODF to normalize mechanisms involved in oxidative stress in the hippocampus.