Elevated neopterin and decreased IL-4, BDNF levels and depression in lymphoma patients receiving R-CHOP chemotherapy.

Objective: Depression is the most commonly observed psychological manifestation experienced by individuals diagnosed with cancer. The purpose of the study was to investigate the association between levels of IL-4, BDNF, neopterin, and depressive symptoms in lymphoma patients receiving consecutive cycles of chemotherapy. Methods: Newly diagnosed lymphoma patients scheduled to receive R-CHOP chemotherapy were enrolled. Effects of R-CHOP on circulatory biomarkers and depressive symptoms were assessed at three-time points [baseline assessment 7 days before the first dose of chemotherapy (TP1), interim assessment after the third cycle of chemotherapy (TP2), and follow-up assessment after the 6th cycle of chemotherapy (TP3)]. Results: Seventy lymphoma patients, with a mean age of 44.17 ± 13.67 years, were enrolled. Patients receiving R-CHOP were found significantly increased neopterin levels between given time points TP1 vs. TP2, TP1 vs. TP3, and TP2 vs. TP3 (p < 0.001). However, IL-4 and BDNF levels significantly decreased with consecutive cycles of chemotherapy (p < 0.001). On Patient Health Questionnaire assessment (PHQ-9), scores of items like loss of interest, feeling depressed, sleep problems, loss of energy, and appetite problems were found significantly affected with consecutive cycles of chemotherapy (p < 0.001). The study found weak negative correlations between IL-4, BDNF, and neopterin levels and changes in PHQ-9 scores at both TP2 and TP3, suggesting a potential inverse relationship between these markers and depression symptoms. Conclusion: In conclusion, the present study suggests a potential link between elevated neopterin levels, decreased IL-4, and BDNF levels, and the presence of depression in lymphoma patients receiving R-CHOP chemotherapy. This study provides valuable insights into understanding the emotional challenges faced by cancer patients, offering information for more personalized interventions and comprehensive support approaches within the oncology setting.

The glutamatergic system in the development of stress-induced depression.

Major depression is one of the most prevalent neuropsychological disorders and affects millions worldwide. In response, the monoaminergic system has been proposed to be one of the major focuses for conventional drugs in the treatment of depression, such as selective serotonin reuptake inhibitor (SSRI). Meanwhile, accumulating evidence suggests a paradigm shift from the monoamine system towards the glutamatergic system (Gerard Sanacora, Giulia Treccani, and Maurizio Popoli 2012) due to the long onset of the monoamine system targeting anti-depressant drugs. Both clinical and pre-clinical data support that glutamatergic system dysfunction were involved in the development of depression. Furthermore, therapeutic approaches that manipulating neuronal activity and N-methyl-D-aspartic acid (NMDA) receptor antagonist were shown to have profound effects in the treatment of depression. Here, I systematically reviewed our current understanding of the involvement of glutamatergic system dysregulation in the development of depression, which potentially could provide the mechanistic basis for future treatment development.

The Interplay between MiR-134/BDNF and LKB1/AMPK/SIRT1 Accentuates the Antidepressant Efficacy of Empagliflozin in Ovariectomized Rats.

Major depressive disorder (MDD) is considered a major cause of suicide worldwide. As previous studies revealed that neuroinflammation is a significant factor in the etiology of MDD, this study proposed to unravel the possible antidepressant effect of Empagliflozin (EMPA) through targeting miRNA-134 (miR-134)/brain-derived neurotrophic factor (BDNF) and liver kinase B1 (LKB1)/adenosine 5'-monophosphate-activated protein kinase (AMPK)/silent information regulator 1 (SIRT1) axes in ovariectomized (OVX) female rats. Rats were assigned randomly to four groups: Sham operation (SO), OVX, OVX + EMPA (10 mg/kg/day, p.o.), and OVX + EMPA + Dorsomorphin (DORSO) (25 µg/day/rat, i.v.). Drugs were administered for 28 days after 2 weeks of surgery. EMPA debilitated OVX-induced depressive-like behavior by mitigating the immobility time in the tail suspension test and forced swimming test. Moreover, EMPA curtailed OVX-induced alterations of serum estradiol, hippocampal serotonin, miR-134 expression, as well as BDNF. EMPA also dwindled OVX-induced changes of hippocampal p-LKB1/LKB1, p-AMPK/AMPK, SIRT1, and inflammatory markers (nuclear factor-kappa-B, interleukin-1 beta, interleukin-6, and tumor necrosis factor alpha). Additionally, the EMPA-treated group exhibited marked improvement in different brain regions' histopathology. However, DORSO coadministration reversed most of EMPA's beneficial effects. The current study displayed the modulatory role of EMPA on miR-134/BDNF and LKB1/AMPK/SIRT1 axes, thus offering a partial explanation of its antidepressant efficacy and proposing EMPA as a novel therapeutic avenue for MDD.

Age and duration of obesity modulate the inflammatory response and expression of neuroprotective factors in mammalian female brain.

Obesity has become a global epidemic and is associated with comorbidities, including diabetes, cardiovascular, and neurodegenerative diseases, among others. While appreciable insight has been gained into the mechanisms of obesity-associated comorbidities, effects of age, and duration of obesity on the female brain remain obscure. To address this gap, adolescent and mature adult female mice were subjected to a high-fat diet (HFD) for 13 or 26 weeks, whereas age-matched controls were fed a standard diet. Subsequently, the expression of inflammatory cytokines, neurotrophic/neuroprotective factors, and markers of microgliosis and astrogliosis were analyzed in the hypothalamus, hippocampus, and cerebral cortex, along with inflammation in visceral adipose tissue. HFD led to a typical obese phenotype in all groups independent of age and duration of HFD. However, the intermediate duration of obesity induced a limited inflammatory response in adolescent females' hypothalamus while the hippocampus, cerebral cortex, and visceral adipose tissue remained unaffected. In contrast, the prolonged duration of obesity resulted in inflammation in all three brain regions and visceral adipose tissue along with upregulation of microgliosis/astrogliosis and suppression of neurotrophic/neuroprotective factors in all brain regions, denoting the duration of obesity as a critical risk factor for neurodegenerative diseases. Importantly, when female mice were older (i.e., mature adult), even the intermediate duration of obesity induced similar adverse effects in all brain regions. Taken together, our findings suggest that (1) both age and duration of obesity have a significant impact on obesity-associated comorbidities and (2) early interventions to end obesity are critical to preserving brain health.

Psychedelic LSD activates neurotrophic signal but fails to stimulate neural stem cells.

Accumulating evidence has shown that some hallucinogens, such as LSD, have fast and persistent effects on anxiety and depression. According to a proposed mechanism, LSD activates the TrkB and HTR2A signaling pathways, which enhance the density of neuronal dendritic spines and synaptic function, and thus promote brain function. Moreover, TrkB signaling is also known to be crucial for neural stem cell (NSC)-mediated neuroregeneration to repair dysfunctional neurons. However, the impact of LSD on neural stem cells remains to be elucidated. In this study, we observed that LSD and BDNF activated the TrkB pathway in human NSCs similarly to neurons. However, unlike BDNF, LSD did not promote NSC proliferation. These results suggest that LSD may activate an alternative mechanism to counteract the effects of BDNF-TrkB signaling on NSCs. Our findings shed light on the previously unrecognized cell type-specificity of LSD. This could be crucial for deepening our understanding of the mechanisms underlying the effects of LSD.

Therapeutic Importance of Exercise in Neuroplasticity in Adults with Neurological Pathology: Systematic Review.

Neuroplasticity is an essential mechanism by which the nervous system shapes and adapts according to functional requirements. Evidence suggests that physical exercise induces a cascade of cellular processes that favours brain plasticity. The Brain Derived Neurotrophic Factor (BDNF) is a neurotrophin closely linked to neuroplasticity that can be increased due to exercise. To verify the effects of therapeutic exercise on neuroplasticity and/or peripheral BDNF levels in neurological conditions in adults, such as stroke, Parkinson's and Alzheimer's diseases and mild cognitive impairment and address its clinical relevance in the treatment of neurological dysfunctions. A systematic review was carried using PUBMED, Web of Science and Scopus databases. Inclusion criteria were: randomized controlled trials or pilot studies; humans with age > 18 yrs with neurological condition; English language; score ≥ 6 in PEDro Scale (moderate to high quality). Reviews, meta-analyses and other articles that did not meet the criteria were excluded. The PRISMA methodology was applied for studies' selection. A total of 9 studies were selected for a systematic and comprehensive analysis. According to these studies, moderate to high intensity aerobic exercise (AE), increases the level of peripheral BDNF and positively influences functional gains in neurological conditions. Larger outcomes are observed in protocols with minimum session duration of 30 minutes, frequency of 3 times/week and intervention duration of 4 weeks. Current evidence shows that moderate to high intensity AE induces neuroplasticity in neurological patients, thus being a fundamental therapeutic strategy to include in interventions aiming to repair/delay neurological dysfunctions.

Immune Cells Promote BDNF Expression by Infiltrated Macrophages via Interleukin 4 in the Cerebral Ischemia of Male Rats.

We reported that infiltrated Ly6C+ macrophages express brain-derived neurotrophic factor (BDNF) only at the cerebral cortex infarct in a rat dMCAO model. However, the changein neuron-expressed BDNF, the niche components that induce the Ly6C+ cells to express BDNF, and the cellular sources of these components, remain unclear. In this study, immunofluorescence double staining was performed to label BDNF and Ly6C on brain sections at 3, 24, and 48 h following distal middle cerebral artery occlusion (dMCAO) of male rats, and to stain BDNF with Ly6C, IL-4R, and IL-10R. A neutralizing anti-IL-4 antibody was injected into the infarct, and the IL-4 and BDNF concentrations in the subareas of the infarct were determined using enzyme-linked immunosorbent assay. To find out the cellular sources of IL-4, the markers for microglia, T cells, and neurons were co-stained with IL-4 separately. In certain infarct subareas, the main BDNF-expressing cells shifted quickly from NeuN+ neurons to Ly6C+ cells during 24-48 h post-stroke, and the Ly6C+/BDNF+ cells mostly expressed IL-4 receptor. Following IL-4 neutralizing antibody injection, the BDNF, IL-4 protein levels, and BDNF+/Ly6C+ cells decreased significantly. The main IL-4-expressing cell type in this infarct subarea is not neuron either, but immune cells, including microglia, monocyte, macrophages, and T cells. The neurons, maintained BDNF and IL-4 expression in the peri-infarct area. In conclusion, in a specific cerebral subarea of the rat dMCAO model, IL-4 secreted by immune cells is one of the main inducers for Ly6C+ cells to express BDNF.

The interplay between BDNF and PGC-1 alpha in maintaining brain health: role of exercise.

Throughout our evolutionary history, physical activity has played a significant role in shaping our physiology. Advances in exercise science have further reinforced this concept by highlighting how exercise can change gene expression and molecular signaling to achieve various beneficial outcomes. Several studies have shown that exercise can alter neuronal functions to prevent neurodegenerative conditions like Parkinson's and Alzheimer's diseases. However, individual genotypes, phenotypes, and varying exercise protocols hinder the prescription of exercise as standard therapy. Moreover, exercise-induced molecular signaling targets can be double-edged swords, making it difficult to use exercise as the primary candidate for beneficial effects. For example, activating PGC-1 alpha and BDNF through exercise could produce several benefits in maintaining brain health, such as plasticity, neuronal survival, memory formation, cognition, and synaptic transmission. However, higher expression of BDNF might play a negative role in bipolar disorder. Therefore, further understanding of a specific mechanistic approach is required. This review focuses on how exercise-induced activation of these molecules could support brain health and discusses the potential underlying mechanisms of the effect of exercise-induced PGC-1 alpha and BDNF on brain health.

Haploinsufficiency of intraflagellar transport protein 172 causes autism-like behavioral phenotypes in mice through BDNF.

INTRODUCTION: Primary cilia are hair-like solitary organelles growing on most mammalian cells that play fundamental roles in embryonic patterning and organogenesis. Defective cilia often cause a suite of inherited diseases called ciliopathies with multifaceted manifestations. Intraflagellar transport (IFT), a bidirectional protein trafficking along the cilium, actively facilitates the formation and absorption of primary cilia. IFT172 is the largest component of the IFT-B complex, and its roles in Bardet-Biedl Syndrome (BBS) have been appreciated with unclear mechanisms. OBJECTIVES: We performed a battery of behavioral tests with Ift172 haploinsufficiency (Ift172+/-) and WT littermates. We use RNA sequencing to identify the genes and signaling pathways that are differentially expressed and enriched in the hippocampus of Ift172+/- mice. Using AAV-mediated sparse labeling, electron microscopic examination, patch clamp and local field potential recording, western blot, luciferase reporter assay, chromatin immunoprecipitation, and neuropharmacological approach, we investigated the underlying mechanisms for the aberrant phenotypes presented by Ift172+/- mice. RESULTS: Ift172+/- mice displayed excessive self-grooming, elevated anxiety, and impaired cognition. RNA sequencing revealed enrichment of differentially expressed genes in pathways relevant to axonogenesis and synaptic plasticity, which were further confirmed by less spine density and synaptic number. Ift172+/- mice demonstrated fewer parvalbumin-expressing neurons, decreased inhibitory synaptic transmission, augmented theta oscillation, and sharp-wave ripples in the CA1 region. Moreover, Ift172 haploinsufficiency caused less BDNF production and less activated BDNF-TrkB signaling pathway through transcription factor Gli3. Application of 7,8-Dihydroxyflavone, a potent small molecular TrkB agonist, fully restored BDNF-TrkB signaling activity and abnormal behavioral phenotypes presented by Ift172+/- mice. With luciferase and chip assays, we provided further evidence that Gli3 may physically interact with BDNF promoter I and regulate BDNF expression. CONCLUSIONS: Our data suggest that Ift172 per se drives neurotrophic effects and, when defective, could cause neurodevelopmental disorders reminiscent of autism-like disorders.

Cannabidiol Modulation of Nicotine-Induced Toxicity: Assessing Effects on Behavior, Brain-Derived Neurotrophic Factor, and Oxidative Stress in C57BL/6 Male Mice.

High doses of nicotine administered to rodents serve as a model for studying anxiety and test compounds' potential anxiolytic effects. At these doses, anxiety in rodents is accompanied by disruption of brain-derived neurotrophic factor (BDNF). The endocannabinoids and nicotine modulate several central nervous system processes via their specific receptors, impacting locomotion, anxiety, memory, nociception, and reward. Cannabidiol (CBD), an active ingredient of Cannabis sativa L., is devoid of psychoactive actions and has gained attention for its anxiolytic, antioxidant, and anti-inflammatory properties, among others. This work aims to examine the potential anxiety-reducing properties of CBD in a well-established experimental mouse model of anxiety-like behavior induced by high doses of nicotine on male C57BL/6 mice. In this context, the open-field behavioral test was specially conducted to assess CBD's effects on anxiety-like behavior and locomotion. Brain neuronal plasticity, modulated by BDNF, along with a diverse array of blood's metabolic markers, was examined as a means of evaluating systemic toxicity under various treatments. Finally, oxidative stress was evaluated through the measurement of glutathione (GSH), superoxide dismutase (SOD), and malondialdehyde (MDA), while pro-inflammatory cytokine assessments were conducted to evaluate redox status and immune system function. Our research suggests that CBD shows potential in reducing anxiety-like behaviors induced by high doses of nicotine, by mitigating changes in BDNF protein levels in cerebral hemispheres and cerebellum. At the same time, CBD targets specific liver enzymes, maintains tissue's systemic toxicity (i.e., renal, kidney, and pancreatic), balances redox status (SOD, GSH, and MDA), and regulates the secretion of pro-inflammatory cytokines (TNF-alpha and IL-6).

Assessment of BDNF and sialic acid levels in children with ADHD: Relation of chronotypes.

OBJECTIVE: Evaluation of the biomarkers and their relations with sleep in attention deficit hyperactivity disorder (ADHD) is important for understanding the impairments in cognitive functioning. In this study, we aimed to investigate the brain-derived neurotrophic factor (BDNF) and sialic acid (Sia) levels, and their possible relations with chronotypes in ADHD. METHODS: The study included 100 drug-naive children with ADHD and 74 healthy children as controls. Conners' Parent Rating Scale-Revised (CPRS-R) scores were used for the severity assessment. Morningness Eveningness Questionnaire (MEQ) was used to determine the chronotypes of participants. ELISA kits were used for the assessment of BDNF and Sia plasma levels. RESULTS: Levels of BDNF and Sia were found to be statistically significantly higher in the ADHD group compared to healthy children (p < 0.001, p < 0.001, respectively). BDNF and Sia levels were found to be higher in the ADHD group with eveningness chronotype (p = 0.045, p = 0.038). The binary logistic regression model was statistically significant (p = 0.033), higher BDNF and Sia levels were assessed as predictive factors for the diagnosis of ADHD. Also, eveningness chronotype was found as a predictive factor of BDNF and Sia levels in ADHD. CONCLUSION: The results indicate that BDNF and Sia levels, which are related to cognitive functions and sleep, increase with the age of ADHD. Eveningness chronotype, connected with the severity of ADHD, is related to BDNF and Sia levels. There is a need for further studies to confirm these results.

Comparing the effect of high-intensity interval exercise and voluntary exercise training on cognitive functions in rats.

It is known that exercise increases brain-derived neurotrophic factor (BDNF) levels in the hippocampus, the brain region responsible for learning and memory, resulting in improved cognitive functions and learning processes. However, it is claimed that different types of exercise cause different responses in the brain. It is thought that lactate and osteocalcin secreted in response to exercise are associated with an increase in BDNF levels. However, there are not enough studies on this subject. This study aimed to compare the effects of high-intensity interval training (HIIT) and voluntary exercise training on cognitive performance and molecular connections. Male rats were randomly divided into control, voluntary exercise training and HIIT groups. The voluntary exercise group had free access to the voluntary wheel for 8 weeks. The HIIT group performed HIIT on the treadmill 3 days a week for 8 weeks. The rats underwent open field (OF), elevated plus maze (EPM) and Morris water maze (MWM) tests 24 h after the last exercise training. Then, after blood was drawn under anesthesia, the rats were sacrificed and their hippocampus tissues were separated. Glucocorticoid and BDNF levels in the blood were evaluated by enzyme-linked immunosorbent assay (ELISA), and osteocalcin and BDNF expressions in the hippocampus were evaluated by real-time quantitative reverse transcription-polymerase chain reaction (RT-PCR). Neither voluntary exercise training nor HIIT had any significant effect on behavioral parameters assessed by OF, EPM and MWM tests. However, BDNF expression in hippocampus tissue was higher in the HIIT group than in the control group. In addition, osteocalcin expression in hippocampus tissue was higher in the HIIT and voluntary exercise groups than in the control group. In conclusion, according to the findings we obtained from this study, although it does not have a significant effect on cognitive functions, the effect of HIIT on brain functions seems to be more effective than voluntary exercise.

Rethinking the role of TRKB in the action of antidepressants and psychedelics.

Antidepressant drugs promote neuronal plasticity, and activation of brain-derived neurotrophic factor (BDNF) signaling through its receptor neuronal receptor tyrosine kinase 2 (NTRK2 or TRKB) is among the critical steps in this process. These mechanisms are shared by typical slow-acting antidepressants, fast-acting ketamine, and psychedelic compounds, although the cellular targets of each drug differ. In this opinion, we propose that some of these antidepressants may directly bind to TRKB and allosterically potentiate BDNF signaling, among other possible effects. TRKB activation in parvalbumin-containing interneurons disinhibits cortical networks and reactivates a juvenile-like plasticity window. Subsequent rewiring of aberrant networks, coupled with environmental stimuli, may underlie its clinical antidepressant effects. The end-to-end hypothesis proposed may stimulate the search for new treatment strategies.

Anxiolytic Action of Dipeptide Mimetic of the BDNF Loop 2 in Adult Animals.

We studied the anti-anxiety effect of a low-molecular-weight mimetic of the BDNF loop 2, hexamethylenediamide bis-(-N-hexanoyl-L-seryl-L-lysine) (GTS-201) in adult animals. GTS-201 at a dose of 5 mg/kg after acute intraperitoneal administration to outbred male and female rats increased the time spent in the open arms and the number of entries into the open arms in the elevated plus maze (EPM). In "highly emotional" male BALB/c mice, GTS-201 exhibited a dose-dependent anxiolytic effect in the EPM in a dose range of 0.5-2.0 mg/kg with a maximum effective dose of 1 mg/kg. These data confirm the previously revealed anti-anxiety properties of GTS-201 in inbred male and female BALB/c mice and rats and indicate the dependence of the pharmacological activity of the BDNF mimetic on animal age.

The Influence of Intestinal Microbiota on BDNF Levels.

The regulation of neurogenesis, the complex process of producing and differentiating new brain tissue cells, is influenced by a complex interaction of internal and external factors. Over the past decade, extensive research has been conducted on neurotrophins and their key role in adult neurogenesis, as well as their impact on diseases such as depression. Among neurotrophins, the brain-derived neurotrophic factor (BDNF) has been the subject of comprehensive studies on adult neurogenesis, and scientific evidence supports its necessity for neurogenesis in the subventricular zone of the hippocampus. A novel area of research is the emerging role of gut microbiota as a significant contributor to neurogenesis and neurotrophin production. Studies have shown that reduced BDNF levels can lead to mood disorders, which are observed in intestinal dysbiosis, characterized by an imbalance in the composition and quantity of the intestinal microbiota. There is evidence in the literature that there is a link between brain function and gut microbiota. Physical activity, and especially the regularity and intensity of exercise, is important in relation to the level of BDNF and the intestinal microbiota. Probiotics, prebiotics and physical activity may have a positive effect on the intestinal microbiota, and therefore also on the level of the brain-derived neurotrophic factor.

Insights into the Role of microRNAs as Clinical Tools for Diagnosis, Prognosis, and as Therapeutic Targets in Alzheimer's Disease.

Neurodegenerative diseases (NDDs) are a diverse group of neurological disorders characterized by alterations in the structure and function of the central nervous system. Alzheimer's disease (AD), characterized by impaired memory and cognitive abilities, is the most prevalent type of senile dementia. Loss of synapses, intracellular aggregation of hyperphosphorylated tau protein, and extracellular amyloid-ß peptide (Aß) plaques are the hallmarks of AD. MicroRNAs (miRNAs/miRs) are single-stranded ribonucleic acid (RNA) molecules that bind to the 3' and 5' untranslated regions of target genes to cause post-transcriptional gene silencing. The brain expresses over 70% of all experimentally detected miRNAs, and these miRNAs are crucial for synaptic function and particular signals during memory formation. Increasing evidence suggests that miRNAs play a role in AD pathogenesis and we provide an overview of the role of miRNAs in synapse formation, Aß synthesis, tau protein accumulation, and brain-derived neurotrophic factor-associated AD pathogenesis. We further summarize and discuss the role of miRNAs as potential therapeutic targets and biomarkers for AD detection and differentiation between early- and late-stage AD, based on recent research. In conclusion, altered expression of miRNAs in the brain and peripheral circulation demonstrates their potential as biomarkers and therapeutic targets in AD.

Changes in BDNF Concentration in Men after Foam Roller Massage.

Massage is one of the oldest forms of therapy practiced since ancient times. Nowadays, it is used in sports practice, recovery from injury, or supportive therapy for various conditions. The practice of massage uses a variety of instruments that facilitate massaging while relieving the stress on the masseur. One of them is a foam roller. Although roller massage is widely used, there are still no scientific studies describing the biological mechanisms of its effects on the body. The purpose of our study was to analyze the effect of roller massage on BDNF levels in men undergoing self-massage 4x/week/7 weeks. The control group consisted of men who did not perform self-massage. Before the test and after the first, third, fifth, and seventh weeks of self-massage, the study participants' blood was drawn, the serum BDNF was determined, and the results were subjected to analysis of variance by ANOVA test. After the first week of self-massage, an increase in BDNF concentration was observed in the self-massage group compared to the control group (p = 0.023). Similarly, changes were observed in week five (p = 0.044) and week seven (p = 0.046). In the massaged group, BDNF concentrations were significantly higher after the first week of self-massage compared to baseline. In the third week of the study, BDNF decreased to a value comparable to the baseline study, then increased significantly in the fifth and seventh weeks compared to the value recorded in the third week (p = 0.049 and p = 0.029). It was significantly higher in week seven compared to week five (p = 0.03). Higher concentrations of BDNF in subjects undergoing roller self-massage may be one of the biological mechanisms justifying the therapeutic effects of massage in both sports and clinical practice. Studies analyzing the stimulation of BDNF synthesis through various massage techniques should be performed on a larger group of healthy individuals, patients after trauma of multiple origins, and sick people with indications for therapeutic massage.

Akkermansia muciniphila improve cognitive dysfunction by regulating BDNF and serotonin pathway in gut-liver-brain axis.

BACKRGROUND: Akkermansia muciniphila, a next-generation probiotic, is known as a cornerstone regulating the gut-organ axis in various diseases, but the underlying mechanism remains poorly understood. Here, we revealed the neuronal and antifibrotic effects of A. muciniphila on the gut-liver-brain axis in liver injury. RESULTS: To investigate neurologic dysfunction and characteristic gut microbiotas, we performed a cirrhosis cohort (154 patients with or without hepatic encephalopathy) and a community cognition cohort (80 participants in one region for three years) and validated the existence of cognitive impairment in a 3,5-diethoxycarbonyl-1,4-dihydrocollidine-induced hepatic injury mouse model. The effects of the candidate strain on cognition were evaluated in animal models of liver injury. The expression of brain-derived neurotrophic factor (BDNF) and serotonin receptors was accessed in patients with fibrosis (100 patients) according to the fibrosis grade and hepatic venous pressure gradient. The proportion of A. muciniphila decreased in populations with hepatic encephalopathy and cognitive dysfunction. Tissue staining techniques confirmed gut-liver-brain damage in liver injury, with drastic expression of BDNF and serotonin in the gut and brain. The administration of A. muciniphila significantly reduced tissue damage and improved cognitive dysfunction and the expression of BDNF and serotonin. Isolated vagus nerve staining showed a recovery of serotonin expression without affecting the dopamine pathway. Conversely, in liver tissue, the inhibition of injury through the suppression of serotonin receptor (5-hydroxytryptamine 2A and 2B) expression was confirmed. The severity of liver injury was correlated with the abundance of serotonin, BDNF, and A. muciniphila. CONCLUSIONS: A. muciniphila, a next-generation probiotic, is a therapeutic candidate for alleviating the symptoms of liver fibrosis and cognitive impairment.

New Insights into Contradictory Changes in Brain-Derived Neurotrophic Factor (BDNF) in Rodent Models of Posttraumatic Stress Disorder (PTSD).

Post-traumatic stress disorder (PTSD) is a neuropsychiatric disorder that may develop after experiencing traumatic events. Preclinical studies use various methods to induce PTSD-like models such as fear-conditioning, single-prolonged stress (SPS), restraint stress, and social defeat. Brain-derived neurotrophic factor (BDNF) is a crucial neurotrophin in mood regulation. Evidence shows BDNF changes in different neuropsychiatric disorders particularly PTSD. This review examined BDNF alterations in preclinical rodent models of PTSD where we demonstrated a wide range of paradoxical changes in BDNF. We found that the fear-conditioning model produced the most inconsistent alterations in BDNF, and suggest that conclusions drawn from these changes be approached with caution. We suggest that BDNF maladaptive changes in social defeat and restraint stress models may be related to the duration of stress, while the SPS model appears to have more consistent results. Ultimately, we propose that evaluating BDNF alterations in the process of treating PTSD symptoms may not be a reliable factor.