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Ho, C.-Y.

Publications and source records attributed to Ho, C.-Y..

3 recordsLinked to original sources

An ncBAF-ETS2 Chromatin-Remodelling Axis Drives Vascular Smooth Muscle Cell Osteogenic Reprogramming in Vascular Calcification

Introduction: Vascular calcification is a detrimental ageing-related pathology that is markedly accelerated in metabolic disorders. It is driven by osteogenic differentiation of vascular smooth muscle cells (VSMCs), however epigenetic regulatory pathways activated early in this transition remain poorly defined. Methods: An in vitro calcification model was developed using primary human aortic VSMCs cultured with or without mineral stress. Epigenetic changes were assessed using targeted PCR arrays and CUT&RUN sequencing. Key findings were validated in vivo using single-cell sequencing datasets from human large arteries and spatial transcriptomic analysis in atherosclerotic carotid plaques. Transcriptomic and CUT&RUN analyses identified gene targets altered by epigenetic remodelling, and molecular tools were applied to study effects on metabolism, inflammation, apoptosis, and calcification. Results: During early calcification in response to mineral stress, SWI/SNF chromatin remodelling complexes shift toward ncBAF enrichment in pre-osteogenic VSMCs. ncBAF complexes activated transcriptional programs involved in inflammation, apoptosis, and glycolysis-all hallmarks of calcifying VSMCs. The transcription factor ETS2 was identified as a novel component of ncBAF complexes. Disruption of ncBAF or ETS2 impaired osteogenic differentiation and calcification. Notably, ETS2 expression was regulated by ncBAF, forming a positive feedback loop that reinforced VSMC phenotypic switching. Co-activation of ETS2 and ncBAF and the resulting transcriptional shifts were confirmed in human arterial single-cell datasets, with osteogenic/inflammatory clusters showing NFkB and RUNX2 activation. Spatial transcriptomics further suggested that a macrophage-rich microenvironment may promote the differentiation of smooth muscle cells toward an overt osteogenic/inflammatory phenotype. Immunohistochemistry showed that ETS2 levels correlated with calcification severity in human vessels supporting the potential clinical relevance of ETS2. Conclusions: Our findings identify a novel epigenetic mechanism in vascular calcification, where ncBAF and ETS2 cooperate to drive VSMC phenotypic switching. This ncBAF-ETS2 axis represents a potential therapeutic target to modulate VSMC plasticity and intervene early in the progression of cardiovascular calcification.

cell biology↗

Detection of oat crown rust disease in Taiwan (2019-2021)

Oat is a minor forage crop grown in Taiwan. Only a few historical records of oat rust disease have been reported in the country, therefore the pathogen population remains poorly characterized. A rust-like disease outbreak was detected at the Experimental Farm of National Taiwan University in 2019, which caused significant damage to the field experiments. To determine the identity of the pathogen responsible for this disease outbreak, we collected infected foliar material. Disease signs suggested infection by the oat crown rust fungus. Hence, common procedures in rust pathology were applied to confirm the identity of the pathogen with phenotypic and molecular diagnostic techniques. A total of 50 field samples from infected oat cultivars were collected in 2019 and five rust isolates were purified in 2020 and 2021. Phylogenetic analysis based on ITS sequences indicated that the pathogen was likely Puccinia coronata f. sp. avenae (Pca), which was further supported by the placement of Taiwanese isolate NTU-01 with other Pca representatives in a phylogenetic tree of Basidiomycete fungi. Phenotyping assays across 36 oat differential lines demonstrated that Taiwanese isolates are phenotypically similar with relatively limited virulence. This study presents the first molecular confirmation of Pca in Taiwan and reports the virulence profiles of Taiwanese Pca population.

microbiology↗

Epidermal SIRT1 and BDNF modulate mechanical allodynia in mouse models of diabetic neuropathy

Diabetic neuropathy is a debilitating disorder characterized by spontaneous and mechanical pain. The role of skin mechanoreceptors in the development of mechanical pain (allodynia) is unclear. We discovered that mice with diabetic neuropathy had decreased sirtuin 1 (SIRT1) deacetylase activity in foot skin, leading to reduced expression of brain-derived neurotrophic factor (BDNF) and subsequent loss of innervation in Meissner corpuscles, a mechanoreceptor expressing the BDNF receptor TrkB. When SIRT1 was depleted from skin, the mechanical allodynia worsened in diabetic neuropathy mice, likely due to retrograde degeneration of the Meissner-corpuscle innervating A{beta} axons and aberrant formation of Meissner corpuscles which may have increased the mechanosensitivity. The same phenomenon was also noted in skin BDNF knockout mice. Furthermore, overexpression of SIRT1 in skin induced Meissner corpuscle reinnervation and regeneration, resulting in significant improvement of diabetic mechanical allodynia. Overall, the findings suggested that skin-derived SIRT1 and BDNF function in the same pathway in skin sensory apparatus regeneration and highlighted the potential of developing topical SIRT1-activating compounds as a novel treatment for diabetic mechanical allodynia.

neuroscience↗