Biology subjects

Phandthong, R.

Publications and source records attributed to Phandthong, R..

6 recordsLinked to original sources

bioRxiv2025

Electronic Cigarette Aerosol Exposure Induces Airway Remodeling in 3D Human Tracheobronchial Epithelial Tissues: From Goblet Cell Hyperplasia to Squamous Metaplasia

Electronic cigarette (EC) aerosols are increasingly recognized for their disruptive effects on airway physiology, yet the temporal progression of epithelial remodeling remains poorly characterized. While squamous metaplasia, mucin hypersecretion, and ciliary dysfunction are hallmark features of smoking-related airway disease, analogous data for EC exposure are limited. To address this gap, we employed a 3D human tracheobronchial epithelial tissue (hTET) model derived from airway basal stem cells and exposed it daily to NJOY ACE "Classic Tobacco" aerosols (1 or 5 puffs) or clean air for 1, 2, or 3 weeks. Remodeling was assessed via immunolabeling and Western blot analysis. MUC5AC expression revealed a transient hypersecretory response, peaking at week 2 and declining by week 3. Multiparametric analysis demonstrated progressive squamous remodeling: early ciliary loss and involucrin upregulation emerged by week 1, with severity increasing in a puff-dependent manner. By week 2, tissues exhibited marked ciliary depletion, altered epithelial thickness, horizontal nuclear reorientation, and elevated involucrin. At week 3, both exposure groups developed a squamous metaplasia phenotype, characterized by involucrin-positive squamous cells replacing ciliated cells. Quantitative analysis confirmed sustained involucrin elevation, with the 1-puff group reaching levels comparable to the 5-puff group by week 3. These findings delineate a sequential pathological trajectory initiated by EC aerosols, progressing from transient goblet cell activation to squamous metaplasia. This human-relevant model underscores the potential for repeated low-level EC exposure to induce airway epithelial remodeling and pathology.

pharmacology and toxicology↗

bioRxiv2023

Endocytosis Inhibitors Block SARS-CoV-2 Pseudoparticle Infection of Mink Lung Epithelium

Both spill over and spill back of SARS-CoV-2 virus have been reported on mink farms in Europe and the United States. Zoonosis is a public health concern as dangerous mutated forms of the virus could be introduced into the human population through spillback. The purpose of our study was to determine the SARS-CoV-2 entry mechanism using mink lung epithelial cell line (Mv1Lu) and to block entry with drug inhibitors. Mv1Lu cells were susceptible to SARS-CoV-2 viral pseudoparticle infection, validating them as a suitable disease model for COVID-19. Inhibitors of TMPRSS2 and of endocytosis, two pathways of viral entry, were tested to identify those that blocked infection. Dyngo4a, a small molecule endocytosis inhibitor, significantly reduced infection, while TMPRSS2 inhibitors had minimal impact, supporting the conclusion that the entry of the SARS-CoV-2 virus into Mv1Lu cells occurs primarily through endocytosis. The small molecule inhibitors that were effective in this study could potentially be used therapeutically to prevent SARS-CoV-2 infection in mink populations. This study will facilitate the development of therapeutics to prevent zoonotic transmission of SARS-CoV-2 variants to other animals, including humans.

cell biology↗

bioRxiv2022

Does Vaping Increase the Likelihood of SARS-CoV-2 Infection? Paradoxically Yes and No

Data on the relationship between electronic cigarettes (ECs) and SARS-CoV-2 infection are limited and contradictory. Evidence indicates that EC aerosols or nicotine increase ACE2, SARS-CoV-2 virus receptors, which increase virus binding and susceptibility. Our objectives were to determine if EC aerosols increased SARS-CoV-2 infection of human bronchial epithelial cells and to identify the causative chemical(s). A 3D organotypic model (EpiAirway) in conjunction with air liquid interface (ALI) exposure was used to test the effects of aerosols produced from JUUL "Virginia Tobacco" and BLU ECs, or individual chemicals (nicotine, propylene glycol, vegetable glycerin (PG/VG), and benzoic acid) on infection using SARS-CoV-2 pseudoparticles. Exposure of EpiAirway to JUUL aerosols increased ACE2, while BLU and lab-made EC aerosols containing nicotine increased ACE2 levels and TMPRSS2 activity, a spike protease that enables viral-cell fusion. Pseudoparticle infection of EpiAirway increased with aerosols produced from PG/VG, PG/VG plus nicotine, or BLU ECs. JUUL EC aerosols did not increase infection above controls. The baseline level of infection in JUUL treated aerosol groups was attributed to benzoic acid, which mitigated the enhanced infection caused by PG/VG or nicotine. The benzoic acid protection from enhanced infection continued at least 48 hours after exposure. TMPRSS2 activity was significantly correlated with e-liquid pH, which in turn was significantly correlated with infection, with lower pH blocking PG/VG and nicotine-induced-enhanced infection. While ACE2 levels increased in EpiAirway tissues exposed to EC aerosols, infection depended on the ingredients of the e-liquids. PG/VG and nicotine enhanced infection, an effect that was mitigated by benzoic acid.

cell biology↗

bioRxiv2022

New Insights into How JUUL Electronic Cigarette Aerosols and Aerosol Constituents Affect SARS-CoV-2 Infection of Human Bronchial Epithelial Cells

BackgroundThe relationship between the use of tobacco products and SARS-CoV-2 infection is poorly understood and controversial. Most studies have been done with tobacco cigarettes, while few have examined the effect of electronic cigarettes (ECs) on SARS-CoV-2 infection. We tested the hypothesis that EC fluids and aerosols with high concentrations of nicotine promote SARS-COV-2 infection by increasing viral entry into human respiratory epithelial cells. MethodsResponses of BEAS-2B cells to authentic JUUL aerosols or their individual constituents (propylene glycol (PG)/vegetable glycerin (VG) and nicotine) were compared using three exposure platforms: submerged culture, air-liquid-interface (ALI) exposure in a cloud chamber, and ALI exposure in a Cultex(R) system, which produces authentic heated EC aerosols. SARS-CoV-2 infection machinery was assessed using immunohistochemistry and Western blotting. Specifically, the levels of the SARS-CoV-2 receptor ACE2 (angiotensin converting enzyme 2) and a spike modifying enzyme, TMPRSS2 (transmembrane serine protease 2), were evaluated. Following each exposure, lentivirus pseudoparticles with spike protein and a green-fluorescent reporter were used to test viral penetration and the susceptibility of BEAS-2B cells to infection. ResultsNicotine, EC fluids, and authentic JUUL aerosols increased both ACE2 levels and TMPRSS2 activity, which in turn increased viral particle entry into cells. While most data were in good agreement across the three exposure platforms, cells were more responsive to treatments when exposed at the ALI in the Cultex system, even though the exposures were brief and intermittent. In the Cultex system, PG/VG, PG/VG/nicotine, and JUUL aerosols significantly increased infection above clean air controls. However, both the PG/VG and JUUL treatments were significantly lower than nicotine/PG/VG. PG/VG increased infection only in the Cultex(R) system, which produces heated aerosol. ConclusionOur data are consistent with the conclusion that authentic JUUL aerosols or their individual constituents (nicotine or PG/VG) increase SARS-CoV-2 infection. The strong effect produced by nicotine was modulated in authentic JUUL aerosols, demonstrating the importance of studying mixtures and aerosols from actual EC products. These data support the idea that vaping increases the likelihood of contracting COVID-19.

cell biology↗

bioRxiv2022

Mammalian Pumilio Proteins Control Cellular Morphology, Migration, and Adhesion

Pumilio proteins are RNA-binding proteins that control mRNA translation and stability by binding to the 3 UTR of target mRNAs. Mammals have two canonical Pumilio proteins, PUM1 and PUM2, which are known to act in many biological processes, including embryonic development, neurogenesis, cell cycle regulation and genomic stability. Here, we characterized a new role of both PUM1 and PUM2 in regulating cell morphology, migration, and adhesion in T-REx-293 cells, in addition to previously known defects in growth rate. Gene ontology analysis of differentially expressed genes in PDKO cells for both cellular component and biological process showed enrichment in categories related to adhesion and migration. PDKO cells had a collective cell migration rate significantly lower than that of WT cells and displayed changes in actin morphology. In addition, during growth, PDKO cells aggregated into clusters (clumps) due to an inability to escape cell-cell contacts. Addition of extracellular matrix (Matrigel) alleviated the clumping phenotype. Collagen IV (ColIV), a major component of Matrigel, was shown to be the driving force in allowing PDKO cells to monolayer appropriately, however, ColIV protein levels remained unperturbed in PDKO cells. This study characterizes a novel cellular phenotype associated with cellular morphology, migration, and adhesion which can aid in developing better models for PUM function in both developmental processes and disease.

molecular biology↗

bioRxiv2020

Menthol in Electronic Cigarettes: A Contributor to Respiratory Disease?

Menthol is widely used in tobacco products. This study compared the effects of menthol on human bronchial epithelium using submerged cultures, a VITROCELL(R) cloud chamber that provides air liquid interface (ALI) exposure without solvents or heating, and a Cultex ALI system that delivers aerosol equivalent to that inhaled during vaping. In submerged culture, menthol significantly increased calcium influx and mitochondrial reactive oxygen species (ROS) via the TRPM8 receptor, responses that were inhibited by a TRPM8 antagonist. VITROCELL(R) cloud chamber exposure of BEAS-2B monolayers increased mitochondrial protein oxidation, expression of the antioxidant enzyme SOD2, activation of NF-{kappa}B, and secretion of inflammatory cytokines (IL-6 and IL-8). Proteomics data collected following ALI exposure of 3D EpiAirway tissue in the Cultex showed upregulation of NRF-2-mediated oxidative stress, oxidative phosphorylation, and IL-8 signaling. Across the three platforms, menthol adversely effected human bronchial epithelium in a manner that could lead to respiratory disease. O_FIG O_LINKSMALLFIG WIDTH=115 HEIGHT=200 SRC="FIGDIR/small/988006v1_ufig1.gif" ALT="Figure 1"> View larger version (27K): org.highwire.dtl.DTLVardef@b86c96org.highwire.dtl.DTLVardef@1e12bd2org.highwire.dtl.DTLVardef@4008corg.highwire.dtl.DTLVardef@c01cad_HPS_FORMAT_FIGEXP M_FIG Graphical Abstract. Mechanism of action of menthol on human bronchial epithelium.Three in vitro platforms were used to study the effect of menthol on bronchial epithelium. In submerged culture (using BEAS-2B cells), menthol produced rapid calcium influx followed by an increase in oxidative stress and inflammatory cytokines. ALI exposure of BEAS-2B cells to unheated menthol in a cloud chamber caused activation of an inflammatory transcription factor (NF-{kappa}B) and oxidative stress. Proteomics analysis of human EpiAirway tissues exposed at the ALI to heated menthol EC aerosols identified changes in the expression of proteins involved in oxidative stress and in an inflammatory response. C_FIG

cell biology↗