Targeting the main protease of SARS-CoV-2 Inside host cells, the RNA genome of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is translated into two polyproteins that are cleaved to give the individual viral proteins. The main viral protease, known as Mpro or 3CLpro, plays a key role in these cleavages, making it an important drug target. Drayman et al . identified eight drugs that target 3CLpro from a library of 1900 clinically safe drugs. Because of the challenge of working with SARS-CoV-2, they started by screening for drugs that inhibit the replication of a human coronavirus that causes the common cold. They then evaluated the top hits for inhibiting SARS-CoV-2 replication and for inhibiting 3CLpro. Masitinib, a broad antiviral, inhibited the main proteases of coronaviruses and picornaviruses and was effective in reducing SARS-CoV-2 replication in mice. —VV
Longitudinal CSF proteomics identifies NPTX2 as a prognostic biomarker of Alzheimer's disease
Abstract Introduction: Biomarkers that reflect pathologic processes affecting neuronal function during preclinical and early stages of Alzheimer's disease (AD) are needed to aid drug development. Methods: A targeted, stable isotope, quantitative mass spectrometry‐based investigation of longitudinal changes in concentrations of previously identified candidate biomarkers was performed in cerebrospinal fluid (CSF) of Alzheimer's Disease Neuroimaging Initiative participants who were classified as cognitively normal (CN; n = 76) or with mild cognitive impairment (MCI; n = 111) at baseline. Results: Of the candidate biomarkers, the CSF concentration of neuronal pentraxin 2 (NPTX2), a protein involved in synaptic function, exhibited rates of change that were significantly different between three comparison groups (i.e., CN vs. MCI participants; AD pathology positive vs. negative defined by phosphorylated tau181/amyloid beta1‐42 ratio; and clinical progressors vs. non‐progressors). The rate of change of NPTX2 also significantly correlated with declining cognition. Discussion: CSF NPTX2 concentration is a strong prognostic biomarker candidate of accelerated cognitive decline with potential use as a therapeutic target.
Identification of NPTX2 as a prognostic biomarker of Alzheimer’s disease through a longitudinal CSF proteomics study in ADNI subjects
AbstractBackgroundMany biomarkers have been identified which are relevant to studies of Alzheimer’s disease (AD), especially pertaining to the evolution of amyloid plaque, tau tangle pathology and loss of brain tissue. There remains, however, the need for additional biomarkers that reflect pathologic processes affecting neuronal function during pre‐clinical and prodromal stages, to help accelerate drug development efforts.MethodA retrospective investigation of longitudinal changes in concentrations of five analytes (CgA, NPTX2, VGF, SCG2, FABP3) was performed in CSF of ADNI subjects. Rates of longitudinal change in these candidate proteins were compared between: a) Cognitively normal subjects (CN; n = 76) versus subjects with mild cognitive impairment (MCI; n = 111) at baseline; b) Subjects categorized as p‐Tau181/Aβ1‐42 ratio positive versus negative at baseline; and c) ‘Progressors’, i.e., subjects who progressed from CN to MCI or MCI to Dementia within a predefined period versus subjects categorized as ‘non‐progressors’. Following a pre‐specified analysis plan involving mixed‐effects linear models adjusting for relevant covariates, the association between changes in each analyte’s concentration and subjects’ clinical progression was quantified.ResultNPTX2, a protein involved in synaptic function, showed the strongest association with baseline clinical diagnosis of MCI, and a positive p‐Tau181/Aβ1‐42 ratio – the biomarker profile indicative of AD. Differences in the rates of decline in NPTX2 concentration between subjects classified as CN and MCI as well as between p‐Tau181/Aβ1‐42 ratio positive and negative subjects were highly significant (p=0.008 and p<0.0001 resp.), suggesting a complex interaction between the rate of decline in subjects at various stages along the disease continuum. Of the five analytes, only the rates of change in NPTX2 concentrations differed between progressors and non‐progressors (mean difference: 0.08 ± 0.02 ng/mL/year); p = 0.0004), further validating the association of changes in NPTX2 concentration and clinical prognosis. Additional exploratory analyses indicated the presence of a correlation between NPTX2 rates of change and declining cognition measured by MMSE (coef. = 0.3, p = 0.02), and Adas‐Cog 13 (coef. = ‐0.3, p = 0.01).ConclusionThese results suggest that NPTX2 concentration may serve as a prognostic biomarker of accelerated cognitive decline in at least a subset of individuals with AD.
Mucosal Inflammatory and Wound Healing Gene Programmes Reveal Targets for Stricturing Behaviour in Paediatric Crohn’s Disease
Abstract Background and Aims Ileal strictures are the major indication for resective surgery in Crohn’s disease [CD]. We aimed to define ileal gene programmes present at diagnosis and linked with future stricturing behaviour during 5-year follow-up, and to identify potential small molecules to reverse these gene signatures. Methods Antimicrobial serologies and pre-treatment ileal gene expression were assessed in a representative subset of 249 CD patients within the RISK multicentre paediatric CD inception cohort study, including 113 that are unique to this report. These data were used to define genes associated with stricturing behaviour and for model testing to predict stricturing behaviour. A bioinformatics approach to define small molecules which may reverse the stricturing gene signature was applied. Results A total of 19 of the 249 patients developed isolated B2 stricturing behaviour during follow-up, while 218 remained B1 inflammatory. Using deeper RNA sequencing than in our previous report, we have now defined an inflammatory gene signature including an oncostatin M co-expression signature, tightly associated with extra-cellular matrix [ECM] gene expression, in those who developed stricturing complications. We further computationally prioritise small molecules targeting macrophage and fibroblast activation and angiogenesis which may reverse the stricturing gene signature. A model containing ASCA and CBir1 serologies and a refined eight ECM gene set was significantly associated with stricturing development by Year 5 after diagnosis {AUC (area under the curve) (95th CI [confidence interval]) = 0.82 [0.7–0.94)}. Conclusions An ileal gene programme for macrophage and fibroblast activation is linked to stricturing complications in treatment of naïve pediatric CD, and may inform novel small molecule therapeutic approaches.