Fecal microbiota transplantation inhibited neuroinflammation of traumatic brain injury in mice via regulating the gut-brain axis

Ginsenoside Rg3 alleviates brain damage caused by chlorpyrifos exposure by targeting and regulating the microbial-gut-brain axis

INTRODUCTION

The utilization of organophosphorus pesticides (OPs) has been demonstrated to exert a substantial positive influence on crop yield enhancement. However, due to the multitude of exposure routes and the persistence of these compounds, humans are routinely exposed to pesticides on a daily basis through dermal contact, inhalation, and ingestion. This has serious consequences for the health of living organisms. The existing research on the effects of organophosphorus pesticides on organisms primarily encompasses the impact on vital organs such as the liver, kidneys, heart, various blood parameters, and potential neurotoxicity, teratogenicity, carcinogenicity, and mutagenic effects. However, there is a paucity of research addressing the alleviation of brain tissue damage in OP pesticide poisoning through the microbial-intestinal-brain axis.

OBJECTIVES

The objective of the present study is to illuminate the biological activity and mechanism of ginsenoside Rg3 in addressing brain injury induced by chlorpyrifos, employing both in vivo and in vitro models. This investigation will elucidate the role of the microbiota-gut-brain axis and the polarization of macrophages in this process.

METHODS AND RESULTS

Ginsenoside Rg3 is characterized by notable antioxidant and neuroprotective properties. The results showed that Rg3 improved the cognitive and learning memory impairment after chlorpyrifos (CPF) exposure in C57 mice, alleviated macrophage infiltration in the hippocampus, repaired synaptic ultrastructural damage and restored the absence of synapse-related proteins (BDNF, SYP, and PSD-95) through behavioral assays, ameliorated neuronal apoptosis and hypothalamo-pituitary-adrenal axis (HPA axis) disorders, and mediated the development of MPA axis disorders, while mediating M1/M2 macrophage polarization and attenuating apoptosis in brain tissue. In intestinal tissues, Rg3 improved the intestinal flora of mice, significantly reduced macrophage infiltration, and down-regulated the expression of pro-inflammatory cytokines (tumor necrosis factor-α, IL-1β, and IL-6), while concurrently augmenting the levels of short-chain fatty acids. And the therapeutic role of Rg3 in ameliorating the brain damage induced by chlorpyrifos exposure was substantiated by protein imprinting through the NLRP3/Caspase-1/IL-1β signaling pathway. Meanwhile, the results of in vitro experiments demonstrated that ginsenoside Rg3 could attenuate CPF-induced inflammatory responses in BV-2 microglia by modulating M1/M2 macrophage polarization.

CONCLUSION

The results of this study confirmed that ginsenoside Rg3 can be utilized as a promising therapeutic strategy to mitigate brain tissue damage resulting from OP-type pesticide poisoning. These findings suggest that Rg3 has the potential to serve as a promising clinical drug for the treatment of organs affected by organophosphorus pesticide poisoning. This study offers novel insights into the application of Rg3 in the context of the microbial-gut-brain axis, providing a theoretical foundation for the development of ginsenoside Rg3 in clinical settings and the future development of novel drugs.

Traumatic Brain Injury and Gut Microbiome: The Role of the Gut-Brain Axis in Neurodegenerative Processes

PURPOSE OF REVIEW

A deeper understanding of the communication network between the gut microbiome and the central nervous system, termed the gut-brain axis (GBA), has revealed new potential targets for intervention to prevent the development of neurodegenerative disease associated with tramatic brain injury (TBI). This review aims to comprehensively examine the role of GBA post-traumatic brain injury (TBI).

RECENT FINDINGS

The GBA functions through neural, metabolic, immune, and endocrine systems, creating bidirectional signaling pathways that modulate brain and gastrointestinal (GI) tract physiology. TBI perturbs these signaling pathways, producing pathophysiological feedback loops in the GBA leading to dysbiosis (i.e., a perturbed gut microbiome, impaired brain-blood barrier, impaired intestinal epithelial barrier (i.e., "leaky gut"), and a maladaptive, systemic inflammatory response. Damage to the CNS associated with TBI leads to GI dysmotility, which promotes small intestinal bacterial overgrowth (SIBO). SIBO has been associated with the early stages of neurodegenerative conditions such as Parkinson's and Alzheimer's disease. Many of the bacteria associated with this overgrowth promote inflammation and, in rodent models, have been shown to compromise the structural integrity of the intestinal mucosal barrier, causing malabsorption of essential nutrients and further exacerbating dysbiosis. TBI-induced pathophysiology is strongly associated with an increased risk of neurodegenerative diseases, including Parkinson's and Alzheimer's diseases, which represents a significant public health burden and challenge for patients and their families. A healthy gut microbiome has been shown to promote improved recovery from TBI and prevent the development of neurodegenerative disease, as well as other chronic complications. The role of the gut microbiome in brain health post-TBI demonstrates the potential for microbiome-targeted interventions to mitigate TBI-associated comorbidities. Promising new evidence on prebiotics, probiotics, diet, and fecal microbiota transplantation may lead to new therapeutic options for improving the quality of life for patients with TBI. Still, many of these preliminary findings must be explored further in clinical settings. This review covers the current understanding of the GBA in the setting of TBI and how the gut microbiome may provide a novel therapeutic target for treatment in this patient population.

Environmental enrichment-induced cognitive recovery after a moderate pediatric traumatic brain injury is associated with the gut microbiota and neuroinflammation

Pediatric traumatic brain injury (TBI) is a significant health concern, yet access to rehabilitation therapies for children remains limited. Environmental enrichment (EE) is a preclinical model of neurorehabilitation that promotes behavioral recovery and reduces neuroinflammation after TBI. While the gut microbiota has recently emerged as a potential therapeutic target for treating TBI sequelae in adults, its role in recovery after pediatric TBI remains unclear. Therefore, our aim was to assess the effect of EE on gut microbiota and its correlation with cognition as well as microglial morphology in a preclinical model of pediatric TBI. Male rats underwent a controlled cortical impact of moderate severity or sham injury at postnatal day 21 and were then randomly assigned to either EE or standard (STD) housing. Cognition was evaluated using the Morris water maze (MWM) on post-injury days 14-19. Microglial morphology and caecum microbiota was characterized on post-injury day 21. Cognitive deficits and increased microglial activation in the ipsilateral cortex were observed in the STD-housed TBI rats but not those in EE. TBI decreased microbiota α-diversity, while PERMANOVA analysis showed that both TBI and EE modified microbiota β-diversity. Furthermore, regression models indicated that microglial morphology in the ipsilateral cortex and Lactobacillus reuteri predicted behavioral outcomes, while Prevotellaceae NK3B31 was associated with microglial morphology. The data suggest that EE mitigates TBI-induced alterations in gut microbiota and that there is a complex interplay between EE, microbiota and microglial morphology that predicts behavioral recovery in pediatric rats.

A critical review of microbiome-derived metabolic functions and translational research in liver diseases

Significant changes in gut microbial composition are associated with chronic liver disease. Using preclinical models, it has been demonstrated that ethanol/alcohol-induced liver disease is transmissible through fecal microbiota transplantation (FMT). So, the survival rate of people with severe alcoholic hepatitis got better, which suggests that changes in the makeup and function of gut microbiota play a role in metabolic liver disease. The leaky intestinal barrier plays a major role in influencing metabolic-related liver disease development through the gut microbiota. As a result, viable bacteria and microbial products can be transported to the liver, causing inflammation, contributing to hepatocyte death, and causing the fibrotic response. As metabolic-related liver disease starts and gets worse, gut dysbiosis is linked to changes in the immune system, the bile acid composition, and the metabolic function of the microbiota in the gut. Metabolic-related liver disease, as well as its self-perpetuation, will be demonstrated using data from preclinical and human studies. Further, we summarize how untargeted treatment approaches affect the gut microbiota in metabolic-related liver disease, including dietary changes, probiotics, antibiotics, and FMT. It discusses how targeted therapies can improve liver disease in various areas. These approaches may improve metabolic-related liver disease treatment options.

Gut microbiota contributes to the intestinal and extraintestinal immune homeostasis by balancing Th17/Treg cells

Gut microbiota is generally considered to play an important role in host health due to its extensive immunomodulatory activities. Th17 and Treg cells are two important CD4+ T cell subsets involved in immune regulation, and their imbalance is closely tied to many immune diseases. Recently, abundant researches have highlighted the importance of gut microbiota in supporting intestinal and extraintestinal immunity through the balance of Th17 and Treg cells. Here, we presented a comprehensive review of these findings. This review first provided an overview of gut microbiota, along with Th17/Treg cell differentiation and cytokine production. Subsequently, the review summarized the regulatory effects of gut microbiota (in terms of species, components, and metabolites) on the Th17/Treg cell balance in the local intestines and extraintestinal organs, such as lung, liver, brain, kidney, and bone. Specifically, the Th17 and Treg cells that can be modulated by gut microbiota originate not only from the gut and extraintestinal organs, but also from peripheral blood and spleen. Then, the microbial therapeutics, including probiotics, prebiotics, postbiotics, and fecal microbiota transplantation (FMT), were also reviewed because of their therapeutic potentials in addressing intestinal and extraintestinal diseases via the Th17/Treg axis. Finally, the review discussed the clinical applications and future study prospects of microbial therapeutics by targeting the Th17/Treg cell balance. In conclusion, this review focused on elucidating the regulatory effects of gut microbiota in balancing Th17/Treg cells to maintain intestinal and extraintestinal immune homeostasis, contributing to the further development and promotion of microbial therapeutics.

Targeting inflammation and gut microbiota with antibacterial therapy: Implications for central nervous system health

The complex symbiotic relationship between inflammation, the gut microbiota, and the central nervous system (CNS) has become a pivotal focus of contemporary biomedical research. Inflammation, as a physiological defense mechanism, plays a dual role as both a protective and pathological factor, and is intricately associated with gut microbiota homeostasis, often termed the "second brain." The gutbrain axis (GBA) exemplifies this multifaceted interaction, where gut health exerts significantly regulatory effects on CNS functions. Antibacterial therapies represent both promising and challenging strategies for modulating inflammation and gut microbiota composition to confer CNS benefits. However, while such therapies may exert positive modulatory effects on the gut microbiota, they also carry the potential to disrupt microbial equilibrium, potentially exacerbating neurological dysfunction. Recent advances have provided critical insights into the therapeutic implications of antibacterial interventions; nevertheless, the application of these therapies in the context of CNS health warrants a judicious and evidence-based approach. As research progresses, deeper investigation into the microbial-neural interface is essential to fully realize the potential of therapies targeting inflammation and the gut microbiota for CNS health. Future efforts should focus on refining antibacterial interventions to modulate the gut microbiota while minimizing disruption to microbial balance, thereby reducing risks and enhancing efficacy in CNS-related conditions. In conclusion, despite challenges, a more comprehensive understanding of the GBA, along with precise modulation through targeted antibacterial therapies, offers significant promise for advancing CNS disorder treatment. Continued research in this area will lead to innovative interventions and improved patient outcomes.

Research progress on intestinal microbiota regulating cognitive function through the gut-brain axis

The intestinal microbiota community is a fundamental component of the human body and plays a significant regulatory role in maintaining overall health and in the management disease states.The intestinal microbiota-gut-brain axis represents a vital connection in the cognitive regulation of the central nervous system by the intestinal microbiota.The impact of intestinal microbiota on cognitive function is hypothesized to manifest through both the nervous system and circulatory system. Imbalances in intestinal microbiota during the perioperative period could potentially contribute to perioperative neurocognitive dysfunction. This article concentrates on a review of existing literature to explore the potential influence of intestinal microbiota on brain and cognitive functions via the nervous and circulatory systems.Additionally, it summarizes recent findings on the impact of perioperative intestinal dysbacteriosis on perioperative neurocognitive dysfunction and suggests novel approaches for prevention and treatment of this condition.

Necrotizing enterocolitis in a term newborn after spontaneous cerebral parenchymal hemorrhage: a case report

BACKGROUND

Necrotizing enterocolitis (NEC) and intracranial hemorrhage are severe emergencies in the neonatal period. The two do not appear to be correlated. However, our report suggests that parenchymal brain hemorrhage in full-term newborns may put patients at risk for NEC by altering intestinal function through the brain-gut axis.

CASE PRESENTATION

We present a case of spontaneous parenchymal cerebral hemorrhage in a full-term newborn who developed early-stage NEC on Day 15.

CONCLUSIONS

It is possible to consider brain parenchymal hemorrhage as a risk factor for the appearance of NEC. Clinicians should be highly cautious about NEC in infants who have experienced parenchymal hemorrhage. This article is the first to discuss the relationship between parenchymal hemorrhage and NEC in full-term newborns.