Biology subjects

Muta, K.

Publications and source records attributed to Muta, K..

3 recordsLinked to original sources

bioRxiv2026

Hepatotoxicity assessment of antimalarial compounds from microorganisms using a liver organ-on-a-chip system

Malaria remains a critical public health threat in sub-Saharan Africa and Southeast Asia owing to the emergence of resistance to gold-standard artemisinin-based combination therapies. This epidemiological shift drives an urgent need to explore novel bioactive compounds for malaria treatment. Microorganisms produce diverse secondary metabolites with potent biological activities. To develop microbe-derived antimalarial drugs, rigorous safety evaluations are crucial, particularly regarding hepatotoxicity. Therefore, we evaluated the hepatotoxic potential of three compounds with antimalarial attributes: thiolutin (NATPP0650), cochliodinol (NATPP0437), and 4'-hydroxy-mycophenolic acid (NATPP0604). Acute hepatotoxic responses were determined by biochemical assays for cell viability and damage in HepG2 cells following 24 h exposure, comparing conventional two-dimensional cultures with an organ-on-a-chip (OOC) system featuring in vivo-like functionality and long-term culture capabilities. In both culture platforms, NATPP0650 and NATPP0437 caused significant toxicity at concentrations of 10 and 50 {micro}M, whereas NATPP0604 was relatively non-toxic. Based on the OOC data, NATPP0650 and NATPP0437 exhibited CC50 values of 3.04 and 2.21 {micro}M, respectively, whereas NATPP0604 had a CC50 value > 50 {micro}M, offering a superior safety profile with a selectivity index > 23.7. Functional assessment of HepG2 OOCs showed that NATPP0650 and NATPP0437 markedly suppressed albumin production at 10 and 50 {micro}M, whereas NATPP0604 showed minimal inhibition. However, long-term (7 days) toxicity testing on the OOC model revealed a critical finding: NATPP0604 exerted delayed hepatotoxic effects that were undetectable in the 24-h study, as evidenced by partial reductions in cell viability at 10 and 50 {micro}M and decreased albumin production across all tested concentrations. These findings demonstrate the therapeutic safety potential of NATPP0604 for further development as an antimalarial drug and underscore the importance of the long-term OOC data in establishing accurate safety margins for future clinical trials.

pharmacology and toxicology↗

bioRxiv2026

Generalisable signatures of anaesthesia in the large-scale functional organisation of the marmoset brain

How the activity and connectivity of the brain support consciousness remains a central question in neuroscience. Recent progress driven by the use of functional MRI has seen growing recognition that large-scale distributed functional organisation of the human and non-human primate brain are systematically and consistently reshaped by anaesthetic-induced unconsciousness, across anaesthetics and across human and macaque. Here, we generalise these results to a different primate species that is gaining traction as model organism in neuroscience, the marmoset (Callithrix jacchus). We also generalise results to an additional anaesthetic, isoflurane, which we compare with propofol and sevoflurane. We report that under anaesthesia with propofol, sevoflurane, or isoflurane, distributed brain activity from functional MRI is increasingly constrained by the underlying structural connectivity across scales. Anaesthesia also induces a collapse of the principal gradient and intrinsic functional geometry of the marmoset brain, coinciding with a breakdown of hierarchical integration. Altogether, the present results indicate generalisable signatures of anaesthesia in the large-scale organisation of the primate brain.

neuroscience↗

bioRxiv2025

Comprehensive profiling of anaesthetised brain dynamics across phylogeny

Intrinsic dynamics of neuronal circuits shape information processing. Combining neuroimaging with causal perturbation offers the opportunity to understand how local dynamics mediate the link between neurobiology and functional repertoire. We compile a unique dataset of multi-scale neural activity during wakefulness and anaesthetic-induced suppression of information processing encompassing human, macaque, marmoset, mouse, zebrafish and nematode. Applying massive feature extraction, we comprehensively characterise local neural dynamics across >6,000 time-series features. Using dynamics as a common space for cross-species comparison reveals a conserved dynamical profile of anaesthesia across species, characterised by shorter intrinsic timescales of neural activity and dampened interregional synchrony. This dynamical regime is experimentally reversed in vivo by deep-brain stimulation of the macaque centromedian thalamus, restoring behavioural responsiveness. Spatially, this conserved dynamical phenotype covaries with conserved transcriptional profiles of excitatory and inhibitory neurotransmission across human, macaque, marmoset and mouse cortex. Biophysical modelling provides a mechanistic link between the macroscale dynamical phenotype of anaesthesia, and microscale effects of key molecular targets on the timescales of synaptic excitation and inhibition. Altogether, comprehensive dynamical phenotyping reveals a shared neural endpoint of anaesthesia: across species and scales, anaesthetics induce spatio-temporal isolation of local neural activity.

neuroscience↗