Neurobiology of disease
December 1, 2023
Youge Qu, Akifumi Eguchi, Li Ma et al.
26 citations
Pretreatment with MDMA for 14 days blocked anhedonia-like behavior and reduced synaptic proteins and brain-derived neurotrophic factor in the prefrontal cortex of mice exposed to chronic restraint stress. Cutting the subdiaphragmatic vagus nerve (vagotomy) blocked these beneficial effects. The gut microbiome showed differences in α-diversity between groups, and specific microbes varied between vehicle- and MDMA-treated stressed mice. Vagotomy prevented increases in three plasma compounds seen in MDMA-treated stressed mice, and two of those compounds correlated positively with several microbes. The data suggest that the gut-brain axis via the subdiaphragmatic vagus nerve may contribute to MDMA-induced stress resilience.
Pharmacology, biochemistry, and behavior
May 1, 2024
Li Ma, Akifumi Eguchi, Guilin Liu et al.
11 citations
Pretreatment with the antidepressant arketamine prevented stress-induced body weight loss, increased behavioral despair, decreased sucrose preference, and reduced synaptic protein expression in the prefrontal cortex of male mice exposed to chronic restraint stress. Gut microbiota analysis indicated that arketamine may restore stress-related changes in microbial abundance. Metabolomics identified four blood metabolites altered between stress-exposed and arketamine-pretreated mice. Network analysis linked synaptic proteins in the prefrontal cortex with specific gut microbes and blood metabolites. These findings suggest that the gut-brain axis, including microbial metabolites, may partly underlie the sustained prophylactic effects of arketamine.
European journal of pharmacology
March 15, 2025
Mingming Zhao, Akifumi Eguchi, Rumi Murayama et al.
6 citations
Intermittent MDMA administration (10 mg/kg, three times weekly for 6 weeks) reduced demyelination in the corpus callosum of mice treated with cuprizone, a chemical that induces myelin loss. The effect appears linked to changes in gut bacteria and metabolites, including β-D-allose, L-sorbose, and carnitine, which correlated negatively with specific microbes such as Romboutsia. These findings suggest MDMA may influence brain demyelination through the gut-brain axis, though further research is needed to clarify the roles of gut microbiota and metabolites.
Clinical psychopharmacology and neuroscience : the official scientific journal of the Korean College of Neuropsychopharmacology
November 30, 2025
Xiayun Wan, Akifumi Eguchi, Rumi Murayama et al.
5 citations
Intermittent doses of MDMA (10 mg/kg three times per week for six weeks) increased whole-body and femoral bone mineral density in ovariectomized mice, compared with vehicle. The treatment shifted bone-remodeling markers toward an antiresorptive profile—lower RANKL and higher osteoprotegerin. Gut microbiota profiling showed reduced Clostridia and enriched Bacilli, and untargeted metabolomics revealed a marked decrease in plasma β-D-allose, a metabolite linked to Lactobacillus johnsonii. These findings suggest that intermittent MDMA may mitigate bone density loss after ovariectomy, potentially through remodeling of a gut microbiota–bone axis. Causal microbial and metabolic mediators remain to be defined.
Progress in neuro-psychopharmacology & biological psychiatry
January 10, 2025
Dan Xu, Akifumi Eguchi, Rumi Murayama et al.
4 citations
Repeated oral administration of MDMA (10 mg/kg/day for 14 days) to male rats significantly altered gut microbiota composition in the small intestine, cecum, and colon, with distinct effects in each region. Analysis of microbial functional capabilities indicated shifts in several metabolic pathways. Untargeted metabolomics showed that MDMA changed levels of two metabolites in the colon—ferulic acid and methylmalonic acid—without affecting levels in blood, small intestine, or cecum. Methylmalonic acid levels in the colon positively correlated with the bacteria Lawsonibacter and Oscillibacter. These results suggest that repeated MDMA treatment can modify gut microbiota across intestinal regions, which may contribute to its pharmacological effects.
Neurobiology of disease
March 1, 2024
Yong Yang, Akifumi Eguchi, Chisato Mori et al.
Depression often accompanies liver cirrhosis, but the underlying reasons are unclear. In mice with cirrhosis induced by common bile duct ligation (CBDL), depression-like behaviors, inflammation, reduced synaptic proteins in the prefrontal cortex, gut microbiota imbalance, and altered blood metabolites were observed. These changes were reversed by severing the subdiaphragmatic vagus nerve, and a single injection of arketamine improved the depression-like behaviors. The findings suggest that the gut-liver-brain axis, via the vagus nerve, mediates depression in cirrhosis, and arketamine may offer a new treatment.
Neuropharmacology
May 1, 2023
Xiayun Wan, Akifumi Eguchi, Lijia Chang et al.
A single injection of arketamine (10 mg/kg) reduced anhedonia-like behavior and reversed the loss of femoral neck cortical and total bone mineral density in mice susceptible to chronic social defeat stress. The abundance of certain gut microbiota and plasma metabolites differed between arketamine-treated and saline-treated susceptible mice, and these microbial and metabolite abundances correlated with bone mineral density. The findings suggest arketamine may improve both depressive symptoms and bone density through a gut-microbiota-bone-brain axis, indicating potential as a therapy for depressed patients with low bone mineral density.