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1.
Nutrients ; 14(5)2022 Mar 05.
Article in English | MEDLINE | ID: covidwho-1732145

ABSTRACT

BACKGROUND: Pulmonary fibrosis (PF) is a chronic, progressive, and, ultimately, terminal interstitial disease caused by a variety of factors, ranging from genetics, bacterial, and viral infections, to drugs and other influences. Varying degrees of PF and its rapid progress have been widely reported in post-COVID-19 patients and there is consequently an urgent need to develop an appropriate, cost-effective approach for the prevention and management of PF. AIM: The potential "therapeutic" effect of the tocotrienol-rich fraction (TRF) and carotene against bleomycin (BLM)-induced lung fibrosis was investigated in rats via the modulation of TGF-ß/Smad, PI3K/Akt/mTOR, and NF-κB signaling pathways. DESIGN/METHODS: Lung fibrosis was induced in Sprague-Dawley rats by a single intratracheal BLM (5 mg/kg) injection. These rats were subsequently treated with TRF (50, 100, and 200 mg/kg body wt/day), carotene (10 mg/kg body wt/day), or a combination of TRF (200 mg/kg body wt/day) and carotene (10 mg/kg body wt/day) for 28 days by gavage administration. A group of normal rats was provided with saline as a substitute for BLM as the control. Lung function and biochemical, histopathological, and molecular alterations were studied in the lung tissues. RESULTS: Both the TRF and carotene treatments were found to significantly restore the BLM-induced alterations in anti-inflammatory and antioxidant functions. The treatments appeared to show pneumoprotective effects through the upregulation of antioxidant status, downregulation of MMP-7 and inflammatory cytokine expressions, and reduction in collagen accumulation (hydroxyproline). We demonstrated that TRF and carotene ameliorate BLM-induced lung injuries through the inhibition of apoptosis, the induction of TGF-ß1/Smad, PI3K/Akt/mTOR, and NF-κB signaling pathways. Furthermore, the increased expression levels were shown to be significantly and dose-dependently downregulated by TRF (50, 100, and 200 mg/kg body wt/day) treatment in high probability. The histopathological findings further confirmed that the TRF and carotene treatments had significantly attenuated the BLM-induced lung injury in rats. CONCLUSION: The results of this study clearly indicate the ability of TRF and carotene to restore the antioxidant system and to inhibit proinflammatory cytokines. These findings, thus, revealed the potential of TRF and carotene as preventive candidates for the treatment of PF in the future.


Subject(s)
COVID-19 , Pulmonary Fibrosis , Tocotrienols , Animals , Bleomycin/toxicity , Carotenoids/adverse effects , Humans , NF-kappa B/metabolism , Phosphatidylinositol 3-Kinases/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Pulmonary Fibrosis/chemically induced , Pulmonary Fibrosis/drug therapy , Pulmonary Fibrosis/prevention & control , Rats , Rats, Sprague-Dawley , SARS-CoV-2 , Signal Transduction , TOR Serine-Threonine Kinases/metabolism , Tocotrienols/adverse effects , Transforming Growth Factor beta/metabolism
2.
J Toxicol Sci ; 46(9): 425-435, 2021.
Article in English | MEDLINE | ID: covidwho-1389030

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes coronavirus disease 2019 (COVID-19). SARS-CoV-2 enters host cells by binding with the receptor angiotensin-converting enzyme 2 (ACE2). While ACE2 is expressed in multiple cell types, it has been implicated in the clinical progression of COVID-19 as an entry point for SARS-CoV-2 into respiratory cells. Human respiratory cells, such as airway and alveolar epithelial type II (ATII) cells, are considered essential for COVID-19 research; however, primary human respiratory cells are difficult to obtain. In the present study, we generated ATII and club cells from human induced pluripotent stem cells (hiPSCs) for SARS-CoV-2 infection and drug testing. The differentiated cells expressed ATII markers (SFTPB, SFTPC, ABCA3, SLC34A2) or club cell markers (SCGB1A1 and SCGB3A2). Differentiated cells, which express ACE2 and TMPRSS2, were infected with SARS-CoV-2. Remdesivir treatment decreased intracellular SARS-CoV-2 viral replication and, furthermore, treatment with bleomycin showed cytotoxicity in a concentration-dependent manner. These data suggest that hiPSC-derived AT2 and club cells provide a useful in vitro model for drug development.


Subject(s)
Adenosine Monophosphate/analogs & derivatives , Alanine/analogs & derivatives , Alveolar Epithelial Cells/drug effects , Antiviral Agents/pharmacology , Bleomycin/toxicity , Cell Differentiation , Induced Pluripotent Stem Cells/drug effects , SARS-CoV-2/drug effects , Toxicity Tests , Adenosine Monophosphate/pharmacology , Alanine/pharmacology , Alveolar Epithelial Cells/metabolism , Alveolar Epithelial Cells/pathology , Alveolar Epithelial Cells/virology , COVID-19/drug therapy , Cell Line , Cell Survival/drug effects , Host-Pathogen Interactions , Humans , Induced Pluripotent Stem Cells/metabolism , Induced Pluripotent Stem Cells/pathology , Induced Pluripotent Stem Cells/virology , Phenotype , SARS-CoV-2/growth & development , SARS-CoV-2/pathogenicity , Virus Replication/drug effects
3.
JCI Insight ; 6(12)2021 06 22.
Article in English | MEDLINE | ID: covidwho-1223641

ABSTRACT

Mice are normally unaffected by SARS coronavirus 2 (SARS-CoV-2) infection since the virus does not bind effectively to the murine version of the angiotensin-converting enzyme 2 (ACE2) receptor molecule. Here, we report that induced mild pulmonary morbidities rendered SARS-CoV-2-refractive CD-1 mice susceptible to this virus. Specifically, SARS-CoV-2 infection after application of low doses of the acute lung injury stimulants bleomycin or ricin caused severe disease in CD-1 mice, manifested by sustained body weight loss and mortality rates greater than 50%. Further studies revealed markedly higher levels of viral RNA in the lungs, heart, and serum of low-dose ricin-pretreated mice compared with non-pretreated mice. Furthermore, lung extracts prepared 2-3 days after viral infection contained subgenomic mRNA and virus particles capable of replication only when derived from the pretreated mice. The deleterious effects of SARS-CoV-2 infection were effectively alleviated by passive transfer of polyclonal or monoclonal antibodies generated against the SARS-CoV-2 receptor binding domain (RBD). Thus, viral cell entry in the sensitized mice seems to depend on viral RBD binding, albeit by a mechanism other than the canonical ACE2-mediated uptake route. This unique mode of viral entry, observed over a mildly injured tissue background, may contribute to the exacerbation of coronavirus disease 2019 (COVID-19) pathologies in patients with preexisting morbidities.


Subject(s)
Bleomycin/toxicity , COVID-19/pathology , Lung Injury , Ricin/toxicity , Animals , Chlorocebus aethiops , Comorbidity , Disease Models, Animal , Female , Lung Injury/chemically induced , Lung Injury/virology , Mice , Vero Cells , Virus Attachment , Virus Internalization/drug effects
4.
Stem Cell Res Ther ; 12(1): 230, 2021 04 12.
Article in English | MEDLINE | ID: covidwho-1192728

ABSTRACT

BACKGROUND: Pulmonary fibrosis (PF), the end point of interstitial lung diseases, is characterized by myofibroblast over differentiation and excessive extracellular matrix accumulation, leading to progressive organ dysfunction and usually a terminal outcome. Studies have shown that umbilical cord-derived mesenchymal stromal cells (uMSCs) could alleviate PF; however, the underlying mechanism remains to be elucidated. METHODS: The therapeutic effects of uMSC-derived extracellular vesicles (uMSC-EVs) on PF were evaluated using bleomycin (BLM)-induced mouse models. Then, the role and mechanism of uMSC-EVs in inhibiting myofibroblast differentiation were investigated in vivo and in vitro. RESULTS: Treatment with uMSC-EVs alleviated the PF and enhanced the proliferation of alveolar epithelial cells in BLM-induced mice, thus improved the life quality, including the survival rate, body weight, fibrosis degree, and myofibroblast over differentiation of lung tissue. Moreover, these effects of uMSC-EVs on PF are likely achieved by inhibiting the transforming growth factor-ß (TGF-ß) signaling pathway, evidenced by decreased expression levels of TGF-ß2 and TGF-ßR2. Using mimics of uMSC-EV-specific miRNAs, we found that miR-21 and miR-23, which are highly enriched in uMSC-EVs, played a critical role in inhibiting TGF-ß2 and TGF-ßR2, respectively. CONCLUSION: The effects of uMSCs on PF alleviation are likely achieved via EVs, which reveals a new role of uMSC-EV-derived miRNAs, opening a novel strategy for PF treatment in the clinical setting.


Subject(s)
Extracellular Vesicles , Mesenchymal Stem Cells , Pulmonary Fibrosis , Animals , Bleomycin/toxicity , Mice , Pulmonary Fibrosis/chemically induced , Pulmonary Fibrosis/genetics , Pulmonary Fibrosis/therapy , Signal Transduction , Transforming Growth Factor beta/genetics , Transforming Growth Factors , Umbilical Cord
5.
Carbohydr Polym ; 247: 116740, 2020 Nov 01.
Article in English | MEDLINE | ID: covidwho-635683

ABSTRACT

Pulmonary fibrosis (PF) is a lung disease with highly heterogeneous and mortality rate, but its therapeutic options are now still limited. Corona virus disease 2019 (COVID-19) has been characterized by WHO as a pandemic, and the global number of confirmed COVID-19 cases has been more than 8.0 million. It is strongly supported for that PF should be one of the major complications in COVID-19 patients by the evidences of epidemiology, viral immunology and current clinical researches. The anti-PF properties of naturally occurring polysaccharides have attracted increasing attention in last two decades, but is still lack of a comprehensively understanding. In present review, the resources, structural features, anti-PF activities, and underlying mechanisms of these polysaccharides are summarized and analyzed, which was expected to provide a scientific evidence supporting the application of polysaccharides for preventing or treating PF in COVID-19 patients.


Subject(s)
Betacoronavirus , Biological Products/therapeutic use , Coronavirus Infections/complications , Pandemics , Pneumonia, Viral/complications , Polysaccharides/therapeutic use , Pulmonary Fibrosis/drug therapy , Animals , Antioxidants/pharmacology , Antioxidants/therapeutic use , Bleomycin/toxicity , COVID-19 , Disease Models, Animal , Drug Evaluation, Preclinical , Forkhead Box Protein O3/physiology , Fungi/chemistry , Heterogeneous Nuclear Ribonucleoprotein D0/physiology , Humans , Macrophages/drug effects , Medicine, Chinese Traditional , Mice , Neutrophils/drug effects , Phytotherapy , Plants, Medicinal/chemistry , Polysaccharides/pharmacology , Pulmonary Fibrosis/chemically induced , Pulmonary Fibrosis/etiology , Pulmonary Fibrosis/prevention & control , RNA, Long Noncoding/antagonists & inhibitors , Rats , SARS-CoV-2 , Seaweed/chemistry , Signal Transduction/drug effects , Smad2 Protein/physiology , Smad3 Protein/physiology , Transforming Growth Factor beta1/antagonists & inhibitors
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