Biology subjects

Lourenco, A. L.

Publications and source records attributed to Lourenco, A. L..

3 recordsLinked to original sources

bioRxiv2022

Perturbations in podocyte transcriptome and biological pathways induced by FSGS associated circulating factors.

Focal segmental glomerulosclerosis (FSGS) is frequently associated with heavy proteinuria and progressive renal failure requiring dialysis or kidney transplantation. However, primary FSGS also has 40-80% risk of recurrence of disease in the transplanted kidney (rFSGS). Multiple circulating factors have been proposed to contribute to the pathogenesis of primary and rFSGS. However, neither the factors nor the downstream effectors specific to individual factors have been identified. The tumor necrosis factor, TNF pathway activation by one or more circulating factors present in the sera of patients with FSGS has been supported by multiple studies. The proposed circulating factors include soluble urokinase-type plasminogen activator receptor (suPAR) and patient derived CD40 autoantibody (CD40autoAb) in the development and recurrence of FSGS. In a human in vitro model, using two novel human antibodies-anti uPAR (2G10) and anti CD40 antibody, we show that the podocyte injury caused by sera from FSGS patients is at least in part mediated by CD40 and suPAR. Additionally, we employ gene expression studies to compare the molecules and pathways activated in response to CD40 autoantibody from rFSGS patients (rFSGS/CD40autoAb) and suPAR, and delineate the unique pathways associated with FSGS injury and transcriptional podocyte alterations with targeted blockade of suPAR and CD40 pathways. Clinical ImpactFocal Segmental Glomerulosclerosis remains a disease without specific therapy for primary disease and high rate of recurrence after kidney transplantation. Circulating factors are implicated in the pathogenesis of FSGS but targeting them for therapy has remained elusive. We propose two potential therapeutic molecules for rFSGS treatment-a human anti-uPAR antibody (2G10) and a humanized anti-CD40 blocking antibody (Bristol Meyer Squibb, 986090) that reverse podocyte injury associated with FSGS in cultured podocytes and can be further tested in pre-clinical and clinical models. Furthermore, we use microarray profiling to identify transcriptional pathways specific to podocyte injury from patient-derived CD40 autoantibodies (rFSGS/CD40autoAb) and suPAR and selective blockade of these pathways to abrogate podocyte injury.

immunology↗

bioRxiv2022

Structure-based identification of naphthoquinones and derivatives as novel inhibitors of main protease Mpro and papain-like protease PLpro of SARS-CoV-2

The worldwide COVID-19 pandemic caused by the coronavirus SARS-CoV-2 urgently demands novel direct antiviral treatments. The main protease (Mpro) and papain-like protease (PLpro) are attractive drug targets among coronaviruses due to their essential role in processing the polyproteins translated from the viral RNA. In the present work, we virtually screened 688 naphthoquinoidal compounds and derivatives against Mpro of SARS-CoV-2. Twenty-four derivatives were selected and evaluated in biochemical assays against Mpro using a novel fluorogenic substrate. In parallel, these compounds were also assayed with SARS-CoV-2 PLpro. Four compounds inhibited Mpro with half-maximal inhibitory concentration (IC50) values between 0.41 {micro}M and 66 {micro}M. In addition, eight compounds inhibited PLpro with IC50 ranging from 1.7 {micro}M to 46 {micro}M. Molecular dynamics simulations suggest stable binding modes for Mpro inhibitors with frequent interactions with residues in the S1 and S2 pockets of the active site. For two PLpro inhibitors, interactions occur in the S3 and S4 pockets. In summary, our structure-based computational and biochemical approach identified novel naphthoquinonal scaffolds that can be further explored as SARS-CoV-2 antivirals.

biochemistry↗

bioRxiv2021

A novel class of TMPRSS2 inhibitors potently block SARS-CoV-2 and MERS-CoV viral entry and protect human epithelial lung cells

The host cell serine protease TMPRSS2 is an attractive therapeutic target for COVID-19 drug discovery. This protease activates the Spike protein of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) and of other coronaviruses and is essential for viral spread in the lung. Utilizing rational structure-based drug design (SBDD) coupled to substrate specificity screening of TMPRSS2, we have discovered a novel class of small molecule ketobenzothiazole TMPRSS2 inhibitors with significantly improved activity over existing irreversible inhibitors Camostat and Nafamostat. Lead compound MM3122 (4) has an IC50 of 340 pM against recombinant full-length TMPRSS2 protein, an EC50 of 430 pM in blocking host cell entry into Calu-3 human lung epithelial cells of a newly developed VSV SARS-CoV-2 chimeric virus, and an EC50 of 74 nM in inhibiting cytopathic effects induced by SARS-CoV-2 virus in Calu-3 cells. Further, MM3122 blocks Middle East Respiratory Syndrome Coronavirus (MERS-CoV) cell entry with an EC50 of 870 pM. MM3122 has excellent metabolic stability, safety, and pharmacokinetics in mice with a half-life of 8.6 hours in plasma and 7.5 h in lung tissue, making it suitable for in vivo efficacy evaluation and a promising drug candidate for COVID-19 treatment.

microbiology↗