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Kodama, N.

Publications and source records attributed to Kodama, N..

4 recordsLinked to original sources

Human-wildlife conflict shows shared spatial predictors across ecological and geographic contexts

Human-wildlife conflict (HWC) is a global challenge for biodiversity conservation, food security, and human well-being. Effective management towards human-wildlife coexistence, recognized as a priority in Target 4 of the Kunming-Montreal Global Biodiversity Framework, requires understanding the drivers of HWC. However, the strong influence of local human and ecological context means that most HWC research focuses on individual case studies, limiting transferability of patterns across contexts. Here, we link local contexts and transferable drivers by testing whether HWC exhibits an intermediate level of organization, in which local predictor profiles are structured by broader ecological, geographic, and taxonomic contexts. After compiling ~11,000 conflict incidents, we construct and compare random forest models across 29 mammalian HWC scenarios spanning diverse species, conflict types, biomes, and continents to identify contexts in which predictor profiles converge. While predictors varied among individual conflicts, HWC scenarios were organized by shared context: conflicts occurring within the same biome tended to have similar predictor profiles, with continent and taxonomic group providing additional structure. Proximity to protected areas was the most consistently important predictor of HWC globally. The likelihood of conflict increased with human population density across nearly all scales and contexts, while distance to roads was also an important predictor in many contexts. Together, these results demonstrate an intermediate level of organization in HWC that reconciles case-specific variation with broader patterns across biomes, continents, and taxonomic groups. This framework provides a basis for scaling mitigation strategies beyond individual case studies while avoiding one-size-fits-all approaches.

ecology↗

Exercising with virtual reality is potentially better for the working memory and positive mood than cycling alone

Although virtual reality (VR) exercise has attracted attention as a factor in exercise habituation due to its mood-enhancing effects, its impact on brain function remains unclear. This study, involving 23 healthy university students, used functional magnetic resonance imaging (fMRI) to explore how VR exercise affects working memory, a key executive function, and its underlying neural mechanisms. Our findings indicate that a 10-min VR exercise session improved mood (arousal and vitality level) and working memory task performance (3-back task) more effectively than exercise or rest alone. Furthermore, the results confirmed that increased vitality from exercise and VR exercise interventions was associated with improved 3-back task performance. However, specific brain regions contributing to this enhancement remain unidentified. These results highlight VR exercise as the optimal exercise program for enhancing working memory function by increasing vitality level. These insights underscore VRs potential as a novel exercise modality with benefits extending beyond exercise adherence to potentially preventing dementia and depression.

neuroscience↗

The gut lactic acid bacteria metabolite, 10-oxo-cis-6,trans-11-octadecadienoic acid, suppresses inflammatory bowel disease in mice by modulating the NRF2 pathway and GPCR-signaling

Various gut bacteria, including Lactobacillus plantarum, possess several enzymes that produce hydroxy fatty acids (FAs), oxo FAs, conjugated FAs, and partially saturated FAs from polyunsaturated FAs as secondary metabolites. Among these derivatives, we identified 10-oxo-cis-6,trans-11-octadecadienoic acid ({gamma}KetoC), a {gamma}-linolenic acid (GLA)-derived enon FA, as the most effective immunomodulator, which inhibited the antigen-induced immunoactivation and LPS-induced production of inflammatory cytokines. The treatment with {gamma}KetoC significantly suppressed proliferation of CD4+ T cells, LPS-induced activation of bone marrow-derived dendritic cells (BMDCs), and LPS-induced IL-6 release from peritoneal cells, splenocytes, and CD11c+ cells isolated from the spleen. {gamma}KetoC also inhibited the release of inflammatory cytokines from BMDCs stimulated with poly-I:C, R-848, or CpG. Further in vitro experiments using an agonist of GPR40/120 suggested the involvement of these GPCRs in the effects of {gamma}KetoC on DCs. We also found that {gamma}KetoC stimulated the NRF2 pathway in DCs, and the suppressive effects of {gamma}KetoC and agonist of GPR40/120 on the release of IL-6 and IL-12 were reduced in Nrf2-/- BMDCs. We evaluated the role of NRF2 in the anti-inflammatory effects of {gamma}KetoC in a dextran sodium sulfate-induced colitis model. The oral administration of {gamma}KetoC significantly reduced body weight loss, improved stool scores, and attenuated atrophy of the colon, in wild-type C57BL/6 and Nrf2+/- mice with colitis. In contrast, the pathology of colitis was deteriorated in Nrf2-/- mice even with the administration of {gamma}KetoC. Collectively, the present results demonstrated the involvement of the NRF2 pathway and GPCRs in {gamma}KetoC-mediated anti-inflammatory responses.

immunology↗

Rose flavor compound β-damascone regulates dendritic cell-mediated immunoresponses by modulating the NRF2 pathway and ameliorates contact hypersensitivity

Dendritic cells (DCs), which are typical antigen-presenting cells, localize to various sites in the body, particularly the front line of infection as sentinels, and are involved in innate and adaptive immune responses. Although the functions of DCs, such as pathogen-induced cytokine production and antigen-specific T cell activation, are important for host defenses against infection and tumorigenesis, the hyper- and/or extended activation of DCs leads to inflammatory and autoimmune diseases. In the present study, {beta}-damascone, a major ingredient of rose fragrance, was selected from an aroma library as a candidate compound that suppresses antigen-induced immune responses. {beta}-Damascone inhibited the functions of DCs, including the antigen-dependent proliferation of T cells, DC-induced Th1 development, and the TLR ligand-induced production of inflammatory cytokines by DCs. The {beta}-damascone treatment also increased the protein level of the transcription factor NRF2, which plays key roles in antioxidant responses, and the transcription of Hmox1, a target gene of NRF2, in DCs. Nrf2-/- DCs induced Th1-development and produced large amount of IL-12p40 even in the presence of {beta}-damascone, whereas these functions by Nrf2+/- DCs were inhibited by {beta}-damascone under the same conditions. The intake of {beta}-damascone suppressed ear swelling in contact hypersensitivity (CHS) model mice, but not in CHS-induced Nrf2-/- mice. Collectively, the present results indicate the potential of the rose aroma compound {beta}-damascone, which suppresses DC-mediated immune responses by activating the NRF2 pathway in DCs, for the prevention and/or attenuation of immune-mediated diseases.

immunology↗