Monosodium glutamate monohydrate 4.276g/100ml / Monosodium aspartate monohydrate 3.924g/100ml solution for infusion bottles

The gut-brain axis plays an integral role in maintaining overall health, with growing evidence suggesting its impact on the development of various neuropsychiatric disorders, including depression. This review explores the complex relationship between gut microbiota and glutamate (Glu) regulation, highlighting its effect on brain health, particularly in the context of depression following certain neurological insults. We discuss how microbial populations can either facilitate or limit Glu uptake, influencing its bioavailability and predisposing to neuroinflammation and neurotoxicity. Additionally, we examine the role of gut metabolites and their influence on the blood-brain barrier and neurotransmitter systems involved in mood regulation. The therapeutic potential of microbiome-targeted interventions, such as fecal microbiota transplantation, is also highlighted. While much research has explored the role of Glu in major depressive disorders and other neurological diseases, the contribution of gut microbiota in post-neurological depression remains underexplored. Future research should focus on explaining the mechanisms linking the gut microbiota to neuropsychiatric outcomes, particularly in conditions such as post-stroke depression, post-traumatic brain-injury depression, and epilepsy-associated depression. Systematic reviews and human clinical studies are needed to establish causal relationships and assess the efficacy of microbiome-targeted therapies in improving the neuropsychiatric sequalae after neurological insults.

Abstract licence: CC BY

This systematic review analyzes monosodium glutamate (MSG) in the Alzheimer's disease-like condition to enhance translational research. Our review seeks to understand how MSG affects the brain and causes degenerative disorders. Due to significant preclinical data linking glutamate toxicity to Alzheimer's disease and the lack of a comprehensive review or meta-analysis, we initiated a study on MSG's potential link. We searched PubMed, ScienceDirect, ProQuest, DOAJ, and Scopus for animal research and English language papers without time constraints. This study used the PRISMA-P framework and PICO technique to collect population, intervention or exposure, comparison, and result data. It was registered in PROSPERO as CRD42022371502. MSG affected mice's exploratory behaviors and short-term working memory. The brain, hippocampus, and cerebellar tissue demonstrated neuronal injury-related histological and histomorphometric changes. A total of 70% of MSG-treated mice had poor nesting behavior. The treated mice also had more hyperphosphorylated tau protein in their cortical and hippocampus neurons. Glutamate and glutamine levels in the brain increased with MSG, and dose-dependent mixed horizontal locomotor, grooming, and anxiety responses reduced. MSG treatment significantly decreased phospho-CREB protein levels, supporting the idea that neurons were harmed, despite the increased CREB mRNA expression. High MSG doses drastically lower brain tissue and serum serotonin levels. In conclusion, MSG showed AD-like pathology, neuronal atrophy, and short-term memory impairment. Further research with a longer time span and deeper behavioral characterization is needed. Systematic review registration: https://www.crd.york.ac.uk/prospero/, identifier [CRD42022371502].

Abstract licence: CC BY

Background/Objectives: Excitotoxicity, primarily caused by excessive glutamate signaling, is a significant contributor to the aetiology of several neurological disorders. Docosahexaenoic acid (DHA), a long-chain omega-3 polyunsaturated fatty acid, is known for its neuroprotective properties, including antioxidants and anti-inflammatory effects. However, the existing literature has not sufficiently reviewed its specific role in glutamate-induced excitotoxicity. This systematic review aimed to provide comprehensive information from the literature on the neuroprotective effects of DHA in models of glutamate-induced neurotoxicity. Methods: A systematic search was conducted in the Cochrane Library, Scopus, Web of Science, PubMed, ScienceDirect, and Google Scholar, following PRISMA 2020 guidelines. The following keywords were used: DHA OR docosahexaenoic acid AND excitotoxicity OR glutamate-induced excitotoxicity OR glutamate-induced neurotoxicity. A total of 475 articles were screened, and 13 original articles published between 2003 and 2025 were included for data extraction. These studies included nine in vivo animal studies, three ex vivo studies, and one in vitro study. The risk of bias was assessed using SYRCLE's methodology. Results: Our findings demonstrate that DHA provides substantial neuroprotection against excitotoxicity through antioxidative, anti-inflammatory, and anti-apoptotic mechanisms. Furthermore, DHA enhances neuronal function and cognitive performance by modulating neurotransmitter levels and glutamate-related signaling pathways. Despite these positive outcomes, heterogeneity across studies suggests that the neuroprotective properties of DHA may be affected by various parameters, such as the source of DHA, treatment dose and duration, age and experimental design. Conclusions: Although previous studies have demonstrated the benefits of DHA in preclinical and clinical settings of neurological disorders, further clinical studies focusing on the modulation of excitotoxicity by DHA are needed to validate its translational efficacy and therapeutic significance.

Abstract licence: CC BY

PurposeTo synthesize the available evidence on the relationship between dietary glutamate or glutamatergic metabolism and glaucomatous neurodegeneration, with emphasis on biomarkers, retinal injury mechanisms, and nutritional, antioxidant, or pharmacological strategies with neuroprotective potential.MethodsThis study was conducted as a systematic and bibliometric literature review following the PRISMA 2020 logic of identification, screening, eligibility, and inclusion. Searches were performed in Web of Science, Scopus, and PubMed for studies published in English between 2020 and 2025. The search strategy combined terms related to glaucoma or ocular neurodegeneration, the glutamatergic axis, and biomarkers, mechanisms, or interventions. After screening and full-text assessment, 39 studies were included in the systematic synthesis. Due to methodological heterogeneity, the evidence was synthesized narratively and comparatively, without meta-analysis.ResultsThe included studies were organized into six thematic clusters: metabolomic, transcriptomic, and diagnostic biomarkers; pharmacological and neuroprotective interventions; nutritional, antioxidant, and natural-compound neuroprotection; oxidative stress, mitochondrial dysfunction, and regulated cell death; neuroinflammation and glia-mediated retinal injury; and glutamatergic excitotoxicity and neurotransmitter imbalance. The evidence indicates that glutamate-related mechanisms in glaucoma are mainly associated with endogenous glutamatergic metabolism, excitotoxicity, impaired glutamate clearance, glutamate-glutamine homeostasis, oxidative and nitrosative stress, mitochondrial dysfunction, ferroptosis, neuroinflammation, and retinal ganglion cell vulnerability. None of the 39 included studies directly evaluated dietary glutamate or monosodium glutamate as the main exposure.ConclusionThe available evidence does not support a direct conclusion that dietary glutamate or MSG intake contributes to glaucoma onset or progression. Instead, current findings mainly support an indirect mechanistic relationship between endogenous glutamatergic dysregulation and glaucomatous neurodegeneration. Pharmacological, antioxidant, metabolic, and natural-compound strategies show neuroprotective potential, particularly in experimental models, but clinical and translational studies are still needed to clarify the role of dietary exposure, glutamate-glutamine metabolism, and targeted neuroprotective interventions in glaucoma.

Abstract licence: CC BY