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Biology subjects

Yang, H.-Y.

Publications and source records attributed to Yang, H.-Y..

8 recordsLinked to original sources

Development of human iPSC-derived cardiomyocytes-based heart-on-a-chip with customized multi-electrode array for drug-induced cardiotoxicity evaluations

The heart is an essential organ at the beginning and end of life. Cardiotoxicity directly related to life is emphasized as an absolute safety factor in drug development, so it is indispensable to evaluate it accurately. That is why establishing a novel platform that can precisely recapitulate human cardiophysiological properties is necessary. Here, we report a human induced pluripotent stem cell (hiPSC)-derived cardiomyocytes-based heart-on-a-chip integrated with a customized multi-electrode array (cMEA), capable of actualizing a cardiac muscle fascicle and surrounding capillaries tridimensionally. The differences in experimental reproducibility, scale of field potential wave, and gene expression patterns according to the two-dimensional cell-level and three-dimensional tissue-level culture are confirmed. Excellent accuracy of drug efficacy/toxicity of the chip is also verified relative to other conventional cell culture platforms by looking at heart rate changes depending on drug type and concentration/time. Additionally, we checked that kinetic/electrophysiological/molecular biological analysis can be performed with our chip by applying motion tracking, cMEA, and RNA sequencing. Thus, our platform is expected to be used as a tool for more exact cardiotoxicity tests with high reproducibility and multi-angle analysis in line with new pharmacological safety assessments such as comprehensive cardiac arrhythmias assessment (CiPA).

bioengineering↗

Fluoxetine Delivery for Wound Treatment Through an Integrated Bioelectronic Device - Pharmacokinetic Parameters and Safety Profile in Swine

Wound infections are a significant medical challenge, often leading to chronicity or systemic infection. Selective serotonin reuptake inhibitors (SSRIs) have emerged as potential non-antibiotic candidates with demonstrated ability to limit growth and biofilm formation in Gram-negative bacteria, in addition to their pro-healing activity. Here, we compared direct delivery of the SSRI fluoxetine by topical bolus dosing to delivery from an iontophoresis bandage device with an actuator for temporally controlled drug delivery, in a porcine excisional wound model. Device delivery of fluoxetine resulted in a maximum concentration of 12.25 ng fluoxetine per mg tissue, compared to 2.926 ng/mg following bolus dosing, and tissue fluoxetine levels were higher after application using the device than after bolus dosing across the range of doses tested (p=0.0041). The half-life of fluoxetine in the wound tissue was 0.988 {+/-} 0.256 days. Fluoxetine was not detected in the pig plasma, and plasma serotonin levels were not affected by the topical application. Fluoxetine delivery using the device, but not bolus delivery, produced tissue concentrations above the minimum inhibitory concentration (MIC) for some clinically important species of bacteria. The experimental device can effectively deliver topical fluoxetine to the wound, producing higher tissue concentrations of fluoxetine at lower cumulative doses compared to bolus dosing, and with minimal risk of off-target effects. The device may simplify wound treatment by reducing the burden for daily drug application, possibly increasing adherence to a prescribed treatment regimen.

bioengineering↗

Native Korean wild mice (Mus musculus): molecular phylogeny and morphometrics

Taxonomic status of house mice in the Korean Peninsula remains poorly understood. Here, we analyze genetic and morphological characteristics of mice from Korea and evaluate their phylogenetic relationships to the well-known primary subspecies. Using a comprehensive set of publicly available genetic data (mtDNA cytb gene), Korean mice including our specimens from islands, mountains, and agricultural fields were identified to Mus mus musculus. External morphology, such as tail ratios of our specimens, resembled previously assigned subspecies (e.g., M. m. molossinus, M. m. utsuryonis, and M. m. yamashinai), suggesting a single subspecific group within M. m. musculus. Korean mice displayed a distinctive landmark configuration around the snout, with a relatively short and slender premaxillary tooth-patch width (PMXW) and a larger maxillary tooth-row length (MXTL) compared to laboratory strains derived from M. m. domesticus. Our investigation provides insights into the phylogenetic relationships and taxonomic status of Korean mice relative to the primary lineages of M. musculus subspecies. Understanding the evolutionary history of Korean M. m. musculus sheds new light on how their spatiotemporal dynamics led to diversification, with the Korean Peninsula serving as an ecological bridge between East Eurasia and neighboring regions.

zoology↗

Lithocholic acid targets TULP3 to activate sirtuins and AMPK to retard ageing

Lithocholic acid (LCA), accumulated in the body during calorie restriction (CR), can confer administered metazoans with the ability to activate AMP-activated protein kinase (AMPK) and retard ageing. However, how LCA is signalled to activate AMPK and elicit the biological effects is unclear. Here, we show that LCA can enhance sirtuins (SIRTs) to deacetylate and subsequently inhibit vacuolar H+-ATPase (v-ATPase), thereby triggering AMPK activation via the lysosomal glucose-sensing pathway. Through proteomic analysis of SIRT1-coimmunoprecipitated proteins, we identify and validate that TUB like protein 3 (TULP3) is a constitutive component of SIRTs. Surprisingly, we found that TULP3 is an LCA receptor, and that the LCA-bound TULP3 activates SIRTs. The activated SIRTs in turn deacetylate the V1E1 subunit of v-ATPase on K52, K99 and K191 residues. Muscle-specific expression of the 3KR mutant of V1E1, mimicking the deacetylated state, dominantly activates AMPK and rejuvenates muscles in aged mice. Moreover, LCA once administered also activates AMPK and extends lifespan and healthspan in nematodes and flies, depending on the TULP3 homologues tub-1 and ktub, respectively. Our study thus elucidates that LCA triggers the TULP3-sirtuin-v-ATPase- AMPK route to manifest benefits of calorie restriction.

physiology↗

Lithocholic acid phenocopies rejuvenating and life-extending effects of calorie restriction

Calorie restriction (CR) is a dietary intervention to promote health and longevity. CR causes various metabolic changes in both the production and circulation of metabolites; however, it remains unclear which of the changed metabolite(s) can account for the physiological benefits of CR. Through metabolomic analysis of metabolites undergoing abundance changes during CR and subsequent functional validation, we found that lithocholic acid (LCA) is the only metabolite that alone can recapitulate the effects of CR, including activation of AMPK and the rejuvenating effects of muscle regeneration, grip strength and running capacity in mice. Interestingly, LCA also activates AMPK and exerts life- and health-extending effects in Caenorhabditis elegans and Drosophila melanogaster, indicating that these animal models are able to transmit the signalling of LCA once administered. Knockout of AMPK abrogates LCA-induced phenotypes, in nematodes and flies, as well as in mice. Together, we have identified that administration of the CR-upregulated metabolite LCA alone can confer anti-ageing benefits to metazoans, in an AMPK-dependent manner.

physiology↗

Quantifying innervation facilitated by deep learning in wound healing

The peripheral nerves (PNs) innervate the dermis and epidermis, which have been suggested to play an important role in wound healing. Several methods to quantify skin innervation during wound healing have been reported. Those usually require multiple observers, are complex and labor-intensive, and noise/background associated with the Immunohistochemistry (IHC) images could cause quantification errors/user bias. In this study, we employed the state-of-the-art deep neural network, DnCNN, to perform pre-processing and effectively reduce the noise in the IHC images. Additionally, we utilized an automated image analysis tool, assisted by Matlab, to accurately determine the extent of skin innervation during various stages of wound healing. The 8mm wound is generated using a circular biopsy punch in the wild-type mouse. Skin samples were collected on days 3,7,10 and 15, and sections from paraffin-embedded tissues were stained against pan-neuronal marker- protein-gene-product 9.5 (PGP 9.5) antibody. On day 3 and day 7, negligible nerve fibers were present throughout the wound with few only on the lateral boundaries of the wound. On day 10, a slight increase in nerve fiber density appeared, which significantly increased on day 15. Importantly we found a positive correlation (R-2 = 0.933) between nerve fiber density and re-epithelization, suggesting an association between re-innervation and re-epithelization. These results established a quantitative time course of re-innervation in wound healing, and the automated image analysis method offers a novel and useful tool to facilitate the quantification of innervation in the skin and other tissues.

molecular biology↗

Peroxiredoxin 5 regulates osteogenic differentiation via interaction with hnRNPK during bone regeneration

Peroxiredoxin 5 (Prdx5) is involved in pathophysiological regulation via the stress-induced cellular response. However, the function of Prdx5 in the bone remains largely unknown. Here, we show that Prdx5 is involved in osteoclast and osteoblast differentiation, resulting in osteoporotic phenotypes in Prdx5 knockout (Prdx5Ko) mice. Through immunoprecipitation and liquid chromatography combined with tandem mass spectrometry analysis, heterogeneous nuclear ribonucleoprotein K (hnRNPK) was identified as a potential binding partner of Prdx5 during osteoblast differentiation in vitro. We found that Prdx5 acts as a negative regulator of hnRNPK-mediated osteocalcin (Ocn) expression. In addition, transcriptomic analysis revealed that in vitro differentiated osteoclasts from the bone marrow-derived macrophages of Prdx5Ko mice showed enhanced expression of several osteoclast-related genes. These findings indicate that Prdx5 might contribute to the maintenance of bone homeostasis by regulating osteoblast differentiation. This study proposes a new function of Prdx5 in bone remodeling that may be used in developing therapeutic strategies for bone diseases.

cell biology↗

Matrix-matched calibration curves for assessing analytical figures of merit in quantitative proteomics

Mass spectrometry is a powerful tool for quantifying protein abundance in complex samples. Advances in sample preparation and the development of data independent acquisition (DIA) mass spectrometry approaches have increased the number of peptides and proteins measured per sample. Here we present a series of experiments demonstrating how to assess whether a peptide measurement is quantitative by mass spectrometry. Our results demonstrate that increasing the number of detected peptides in a proteomics experiment does not necessarily result in increased numbers of peptides that can be measured quantitatively.

biochemistry↗