Chondrosia reniformis is a common marine demosponge showing many peculiarities, lacking silica spicules and with a body entirely formed by a dense collagenous matrix. In this paper, we have described the identification of a new cytotoxic protein (chondrosin) with selective activity against specific tumor cell lines, from C. reniformis, collected from the Liguria Sea. Chondrosin was extracted and purified using a salting out approach and molecular weight size exclusion chromatography. The cytotoxic fractions were then characterized by two-dimensional gel electrophoresis and mass spectrometry analysis and matched the results with C. reniformis transcriptome database. The procedure allowed for identifying a full-length cDNA encoding for a 199-amino acids (aa) polypeptide, with a signal peptide of 21 amino acids. The mature protein has a theoretical molecular weight of 19611.12 and an IP of 5.11. Cell toxicity assays showed a selective action against some tumor cell lines (RAW 264.7 murine leukemia cells in particular). Cell death was determined by extracellular calcium intake, followed by cytoplasmic reactive oxygen species overproduction. The in silico modelling of chondrosin showed a high structural homology with the N-terminal region of the ryanodine receptor/channel and a short identity with defensin. The results are discussed suggesting a possible specific interaction of chondrosin with the Cav 1.3 ion voltage calcium channel expressed on the target cell membranes.

Coronavirus disease 2019 (COVID-19) in hemodialysis patients (HD) is characterized by heterogeneity of clinical presentation and outcomes. To stratify patients, we collected clinical and laboratory data in two cohorts of HD patients at COVID-19 diagnosis and during the following 4 weeks. Baseline and longitudinal values were used to build a linear mixed effect model (LME) and define different clusters. The development of the LME model in the derivation cohort of 17 HD patients (66.7 ± 12.3 years, eight males) allowed the characterization of two clusters (cl1 and cl2). Patients in cl1 presented a prevalence of females, higher lymphocyte count, and lower levels of lactate dehydrogenase, C-reactive protein, and CD8 + T memory stem cells as a possible result of a milder inflammation. Then, this model was tested in an independent validation cohort of 30 HD patients (73.3 ± 16.3 years, 16 males) assigned to cl1 or cl2 (16 and 14 patients, respectively). The cluster comparison confirmed that cl1 presented a milder form of COVID-19 associated with reduced disease activity, hospitalization, mortality rate, and oxygen requirement. Clustering analysis on longitudinal data allowed patient stratification and identification of the patients at high risk of complications. This strategy could be suitable in different clinical settings.

Over the last few decades, scientists' attention has shifted from neuronal to non-neuronal cells to explain the mechanisms at the basis of neurodegenerative disorders, including amyotrophic lateral sclerosis (ALS). ALS is a multifactorial and multicellular disease in which microglia have a central role, during disease progression. We previously demonstrated that metabotropic glutamate receptor 5 (mGluR5) is dysfunctional in the spinal cord of the SOD1^G93A ALS mice, and its in-vivo genetic or pharmacological dampening ameliorates disease outcome and astrocyte and microglia reactivity. Here, we studied the expression of typical phenotype-related markers during the disease progression in spinal cord microglia cells acutely isolated from early asymptomatic and late symptomatic SOD1^G93A ALS mice. Moreover, we investigated whether reducing mGluR5 affected the microglia phenotype and function. In contrast to what we previously observed in astrocytes, mGluR5 expression decreased during disease progression in microglia acutely isolated from adult SOD1^G93A mice. In-vivo genetic mGluR5 downregulation did not affect microglia phenotype-relevant markers, which evidenced a unique expression distribution. Conversely, mGluR5 reduction ameliorated redox balance and bioenergetics of adult microglia. Microglia cultured from the spinal cord of SOD1^G93A pups showed that in-vitro mGluR5 pharmacological manipulation by the negative allosteric modulator CTEP partially modified their bioenergetic and oxidative status. Overall, our results suggest that mGluR5 manipulation ameliorates microglia phenotype and function in ALS by both direct and indirect mechanisms. Consequently, we hypothesised that the improvement of microglia reactive status by in-vivo mGluR5 downregulation or CTEP pharmacological modulation is supported by ameliorated bioenergetic metabolism, and the indirect astrocyte's phenotype change that promotes an improvement of the surrounding environment.