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Hua, M.

Publications and source records attributed to Hua, M..

6 recordsLinked to original sources

Galectin-3 is Necessary for Selective Cathartocytosis, which Expedites the Development of Proliferative Gastric SPEM

The expression and secretion of sulfated colonic-type mucins is a feature of high-risk metaplasias of the gastrointestinal foregut (Barretts esophagus, type III intestinal metaplasia of the stomach, and pancreatic intraepithelial neoplasia). Galectin-3 is a lectin that preferentially associates with galactose modified by a 3-O-sulfate relative to its unmodified counterparts and is upregulated as the tissue transitions to high-risk metaplasia, dysplasia, and cancer. Since both galectin-3 and sulfated glycotopes are aberrantly and concurrently overexpressed in high-risk premalignant and malignant tissue transformations, we sought to investigate the role of galectin-3 in the metaplastic reaction. We found that injury induces the expression of Lgals3 at the RNA and protein levels. Unlike cancer cell lines, we show that in vivo galectin-3 colocalized with sulfomucins in zymogenic granules of the gastric chief cell. Utilizing a synchronous, chemically-induced murine model that produces spasmolytic polypeptide expressing metaplasia, we found that galectin-3 facilitates cathartocytosis of the vesicles it resides in, but not organelles lacking LGALS3. Inhibition of cellular downscaling resulted in delayed expression of the metaplastic transcription factor Sox9 as well as proliferation. Here, we present a new role for galectin-3 in promoting the transition from normal, homeostatic tissue to metaplasia and our data suggest that cathartocytosis represents an unconventional secretory pathway for galectin-3, which has been a matter of controversy as galectins are not secreted via canonical pathways.

cancer biology↗

Perm1 Gene Therapy Mitigates PRDM16-Associated Cardiomyopathy

BackgroundPathogenic variants in PR domain containing 16 (PRDM16) cause pediatric and adult cardiomyopathies characterized by ventricular dilation, systolic dysfunction, and impaired metabolic maturation. Cardiac deficiency of PRDM16 alters metabolic gene expression and long-chain fatty acid (FA) metabolites. However, the downstream mediators involved are not well characterized. Furthermore, whether improving mitochondrial FA metabolism can prevent PRDM16-associated cardiomyopathy is currently unknown. MethodsIn vivo and in vitro approaches using patient-induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs) and mouse models with Prdm16 deletion/mutation were employed. Transcriptomics and proteomics analyses were conducted, and adeno-associated virus (AAV)-mediated therapy was tested. ResultsHere, we show that a defect in FA metabolism is an early hallmark of PRDM16 cardiac deficiency. We show, for the first time, that PERM1 is a direct downstream target of PRDM16 and is involved in the regulation of FA metabolism through coordinated action with PGC1. Most importantly, neonatal delivery of AAV9-Perm1 in cardiac-specific Prdm16 knockout (Prdm16 cKO) mice markedly improved contractile parameters, reduced left ventricular (LV) dilation, and extended survival. These cardioprotective effects of PERM1 gene therapy occurred independent of restoring FA oxidation. Transcriptional and proteomic analyses of AAV-Perm1-treated Prdm16 cKO mice demonstrated significant improvements in mitochondrial cristae architecture, preservation of sarcomere organization, reduced cardiomyocyte apoptosis, attenuated myocardial fibrosis, and diminished cardiac remodeling. ConclusionsWe identify PERM1 as a direct downstream effector of PRDM16 and uncover a previously unrecognized PRDM16-PGC1-PERM1 axis essential for FA metabolic regulation in the heart. Perm1 gene therapy ameliorated PRDM16-associated cardiomyopathy through post-transcriptional mechanisms involving preservation of mitochondrial and sarcomere integrity. The current study provides preclinical evidence suggesting that Perm1 gene therapy may be a promising therapeutic target to improve the cardiac outcomes of patients affected by pathogenic PRDM16 variants.

physiology↗

Unraveling the Toxicological Effects of Hydroxyacetone - A Reaction Product in Electronic Cigarette Aerosols

Hydroxyacetone has been detected at high concentrations (up to [~]12 mg/mL) in electronic cigarette (EC) aerosols, including those derived from products associated with adverse health effects. Given the limited understanding of its inhalation toxicology, we investigated hydroxyacetones impact on human airway epithelial cells. Acute exposures at the air-liquid interface (ALI) using 3D EpiAirway tissues--a surrogate for human tracheobronchial epithelium--were analyzed via proteomics. Differential expression analysis identified numerous affected proteins, with enrichment pointing to alterations in mitochondrial function and actin cytoskeletal disruption as major targets. Ingenuity Pathway Analysis (IPA) highlighted "Mitochondrial Dysfunction" and "NRF2-Mediated Oxidative Stress" among top toxicological categories, and "Nuclear Cytoskeletal Signaling" as a key canonical pathway. To validate and extend these findings, submerged cultures of BEAS-2B cells were exposed to hydroxyacetone (0.01-10 mg/mL) and assessed for mitochondrial activity, oxidative stress, and F-actin integrity. At 1 mg/mL, mitochondrial membrane potential and reactive oxygen species (ROS) increased, with elevated hydrogen peroxide detected in the culture medium. At 10 mg/mL, mitochondrial activity declined significantly, accompanied by cell rounding and apoptotic blebbing within 2 hours. F-actin destabilization occurred at 1, 3.33, and 10 mg/mL, with cytoplasmic and perinuclear filaments more affected than cortical actin. Findings from ALI and submerged models were concordant, supporting hydroxyacetone-induced mitochondrial stress, oxidative damage, and cytoskeletal disruption. These results suggest that hydroxyacetone concentrations found in EC aerosols may contribute to respiratory toxicity and warrant further investigation.

pharmacology and toxicology↗

An ancient transcription activator is required for the multiciliogenesis program

Multiciliogenesis is an evolutionarily conserved process required a unique transcriptional program. The mechanisms governing multiciliogenesis are incompletely understood. Here we show that an ancient transcription activator, Edf1, is essential for the multiciliogenesis program. Mice lacking Edf1 exhibit postnatal hydrocephalus and delayed multiciliated cells (MCCs) differentiation. Functional studies reveal that MCCs in Edf1-/- mice have defects in tissue-level polarity and reduced motility. These defects result in abnormal cerebrospinal fluid (CSF) dynamics in vivo, potentially contributing to the development of hydrocephalus. Intriguingly, we found that the expression of pivotal ciliary transcription factors was decreased in Edf1-/- mice. Collectively, our data suggest that Edf1 modulates the multiciliogenesis by regulating the transcription of important ciliary transcription factors required for ciliary gene expression.

cell biology↗

Analysis of Body-Fin Cooperative Propulsion Mechanism of Koi Carp Using Pose Estimation

Advances in modern deep learning-based computer vision perception techniques have revolutionized animal movement research methods. These techniques have also opened up new avenues for studying fish swimming. To that end, we have developed a visual perception system based on pose estimation to analyze fish swimming. Our system can quantify fish motion by 3D fish pose estimation and dynamically visualize the motion data of marked keypoints. Our experimental results show that our system can accurately extract the motion characteristics of fish swimming, which analyze how fish bodies and fins work together during different swimming states. This research provides an innovative idea for studying fish swimming, which can be valuable in designing, developing, and optimizing modern underwater robots, especially multi-fin co-driven bionic robotic fish. The code and dataset are available at https://github.com/wux024/AdamPosePlug. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=123 SRC="FIGDIR/small/507033v6_ufig1.gif" ALT="Figure 1"> View larger version (51K): org.highwire.dtl.DTLVardef@1b0ebfaorg.highwire.dtl.DTLVardef@547222org.highwire.dtl.DTLVardef@112addorg.highwire.dtl.DTLVardef@1153407_HPS_FORMAT_FIGEXP M_FIG C_FIG

animal behavior and cognition↗

Identification of eight SARS-CoV-2 ORF7a deletion variants in 2,726 clinical specimens

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) ORF7a, the ortholog of SARS-CoV ORF7a, is a type I transmembrane protein and plays an important role in virus-host interactions. Deletion variants in ORF7a may influence virulence, but only a few such isolates have been reported. Here, we report 8 unique ORF7a deletion variants of 6 to 96 nucleotides in length identified from 2,726 clinical specimens collected in March of 2020.

microbiology↗