ABSTRACT
Objective: Immunohistochemistry of post-mortem lung tissue from Covid-19 patients with diffuse alveolar damage demonstrated marked increases in chondroitin sulfate and CHST15 and decline in N-acetylgalactosamine-4-sulfatase. Studies were undertaken to identify the mechanisms involved in these effects. Method(s): Human primary small airway epithelial cells (PCS 301-010;ATCC) were cultured and exposed to the SARSCoV- 2 spike protein receptor binding domain (SPRBD;AA: Lys310-Leu560;Amsbio). Expression of the spike protein receptor, angiotensin converting enzyme 2 (ACE2), was enhanced by treatment with Interferon-beta. Promoter activation, DNA-binding, RNA silencing, QPCR, Western blots, ELISAs, and specific enzyme inhibitors were used to elucidate the underlying molecular mechanisms. Result(s): Treatment of the cultured cells by the SPRBD led to increased CHST15 and CHST11 expression and decline in ARSB expression. Sulfotransferase activity, total chondroitin sulfate, and sulfated glycosaminoglycan (GAG) content were increased. Phospho-T180/T182-p38-MAPK and phospho- S423/S425-Smad3 were required for the activation of the CHST15 and CHST11 promoters. Inhibition by SB203580, a phospho-p38 MAPK inhibitor, and by SIS3, a Smad3 inhibitor, blocked the CHST15 and CHST11 promoter activation. SB203580 reversed the SPRBD-induced decline in ARSB expression, but SIS3 had no effect on ARSB expression or promoter activation. Phospho-p38 MAPK was shown to reduce retinoblastoma protein (RB) S807/S811 phosphorylation and increase RB S249/T252 phosphorylation. E2F-DNA binding declined following exposure to SPRBD, and SB203580 reversed this effect. This indicates a mechanism by which SPRBD, phospho-p38 MAPK, E2F, and RB can regulate ARSB expression and thereby impact on chondroitin 4-sulfate and dermatan sulfate and molecules that bind to these sulfated GAGs, including Interleukin-8, bone morphogenetic protein-4, galectin-3 and SHP-2 (Src homology region 2-containing protein tyrosine phosphatase 2). Conclusion(s): The enzyme ARSB is required for the degradation of chondroitin 4-sulfate and dermatan sulfate, and accumulation of these sulfated GAGs can contribute to lung pathophysiology, as evident in Covid-19. Some effects of the SPRBD may be attributable to unopposed Angiotensin II, when Ang1-7 counter effects are diminished due to binding of ACE2 with the SARS-CoV-2 spike protein and reduced production of Ang1-7. Aberrant cell signaling and activation of the phospho-p38 MAPK and Smad3 pathways increase CHST15 and CHST11 production, which can contribute to increased chondroitin sulfate in infected cells. Decline in ARSB may occur as a consequence of effects of phospho-p38 MAPK on RB phosphorylation and E2F1 availability. Decline in ARSB and the resulting impaired degradation of sulfated GAGs have profound consequences on cellular metabolic, signaling, and transcriptional events. Funding is VA Merit Award.Copyright © 2023 The American Society for Biochemistry and Molecular Biology, Inc.
ABSTRACT
Introduction: Federally Qualified Health Centers (FQHCs) are funded by the Health Resources and Services Administration (HRSA) to provide primary care services to low-income and underinsured individuals. Los Angeles County (LAC) is a large, diverse county with greater than 10.2 million residents and 8 distinct Service Planning Areas (SPAs) that represent specific geographic regions with variable resources. We aimed to describe colorectal cancer (CRC) screening rates (CRCSR) and the screening rate change (SRCs) in LAC overall and for each SPA between 2019 and 2020 to determine where resources are most needed for CRCSR recovery following the COVID-19 pandemic. Method(s): Our data source was the Uniform Data System (UDS), which includes quality data for the FQHCs funded by HRSA. We determined 2019 and 2020 CRCSR for LAC FQHCs overall and for each FQHC, including average-risk patients age 50-74. We then separated FQHCs into quartiles based on SRC and performed mixed-effects logistic regression to determine FQHC-level characteristics associated with the largest decline in CRCSR from 2019 to 2020 (i.e., predictors of category SRC Q1). Lastly, we determined SRC for each SPA in LAC. Result(s): In 2019, there were 58 FQHCs in LAC with 326,473 patients eligible for CRC screening. In 2020, there were 59 FQHCs with 350,405 eligible patients. The median 2020 CRCSR in LAC FQHCs was 37.3%, down from 48.0% in 2019 (2020 median SRC= -9.6%) (Table). In the regression model among all LAC FQHCs, those with higher proportions of patients preferring a non-English language had significantly higher odds of having the largest decline in CRCSR from 2019 to 2020 (SRC Q1) (aOR=3.25, 95% CI=1.22-8.65;data not shown). CRCSR decreased from 2019 to 2020 in all SPAs with SRC ranging from -17.0% (South Bay) to -1.4% (West LA) (Figure). Conclusion(s): In Los Angeles County FQHCs, CRC screening rates were higher than the national FQHC average in 2019 however declined considerably between 2019 and 2020. The decline in CRC screening rates was highest in FQHCs serving a higher proportion of patients with a preference for a non-English language and varied by county region. Our findings highlight the need for targeted measures, including language-appropriate resources, to improve CRC screening uptake in FQHCs that provide care to some of the most historically marginalized individuals.
ABSTRACT
RATIONALE: The proteomic responses of hospitalized patients with SARS Co-V-2 infection may provide insight into risk, time course, and mechanisms associated with this infection. We used a high throughput proteomic platform to examine proteins that were differentially expressed relative to the length of hospital stay (LOS). METHOD:26 patients, hospitalized with SARS CoV-2 infection (mean age 48 yrs, 44% women) had blood samples obtained within 72 hours of admission. Initial plasma samples were analyzed from patients who were hospitalized for < 3 days (n=6), < 7days (n=12) and > 7 days (n=8) of LOS and compared to healthy controls (HC, n=8). Samples were analyzed with the modified aptamer-based array (SomaScan) that measures more than 7,000 human proteins representing different molecular pathways and gene families. Differentially regulated proteins with > 1.5 fold change and a false discovery rate of 5% were analyzed using the Ingenuity Pathway Analysis (IPA). Unique protein categories associated with LOS were assessed. RESULT: Compared to HC, differentially expressed proteins were detected among the 3 groups: 461 at < 3 days, 1,635 proteins at < 7 days and 1,738 proteins in >7 days. 407 proteins were common among all hospitalized COVID 19 individuals independent of LOS and 12, 250 and 361 proteins were uniquely present at < 3 days, < 7 days and > 7 days respectively compared to HC. The table below demonstrates the top highly enriched canonical pathway, molecular function and upstream regulator of differentially expressed proteins. The temporal sequence of these protein networks varied with LOS. Representative examples include early responses;platelet membrane glycoprotein GP6 signaling pathway that involves the FcR gamma-chain and the Src kinases linked to platelet aggregation, signaling involved in T cell receptor-mediated IL-2 production (TEC kinase). Less than 7 days include diacylglycerol associated with T cell activation, carnitine palmitoyltransferase associated with mitochondrial beta-oxidation of long chain fatty acids. CXCR4 a receptor for stromal -cell derived factor 1 and associated with COVID-19 prognosis. Late responses after 7 days include pathways involved in remodeling of epithelial adherens junctions. CONCLUSIONS : A high throughput proteomic approach provides insight into the dynamic regulation of protein pathways associated with the progression of SARS-Co-V2 infection. This may provide additional insight into risk and mechanisms associated with outcomes in COVID. (Table Presented).