Diabetic nephropathy (DN) is a leading cause of ESRD in the United States, but the molecular mechanisms mediating the early stages of DN are unclear. To assess global changes that occur in early diabetic kidneys and to identify proteins potentially involved in pathogenic pathways in DN progression, we performed proteomic analysis of diabetic and nondiabetic rat glomeruli. Protein S (PS) among the highly upregulated proteins in the diabetic glomeruli. PS exerts multiple biologic effects through the Tyro3, Axl, and Mer (TAM) receptors. Because increased activation of Axl by the PS homolog Gas6 has been implicated in DN progression, we further examined the role of PS in DN. In human kidneys, glomerular PS expression was elevated in early DN but suppressed in advanced DN. However, plasma PS concentrations did not differ between patients with DN and healthy controls. A prominent increase of PS expression also colocalized with the expression of podocyte markers in early diabetic kidneys. In cultured podocytes, high-glucose treatment elevated PS expression, and PS knockdown further enhanced the high-glucose-induced apoptosis. Conversely, PS overexpression in cultured podocytes dampened the high-glucose- and TNF--induced expression of proinflammatory mediators. Tyro3 receptor was upregulated in response to high glucose and mediated the anti-inflammatory response of PS. Podocyte-specific PS loss resulted in accelerated DN in streptozotocin-induced diabetic mice, whereas the transient induction of PS expression in glomerular cells attenuated albuminuria and podocyte loss in diabetic OVE26 mice. Our results support a protective role of PS against glomerular injury in DN progression.

Background: Epigenetic mechanisms are critical in the pathogenesis of pulmonary arterial hypertension (PAH). Previous studies have suggested that hypermethylation of the Bone Morphogenetic Protein Receptor Type 2 (BMPR2) promoter is associated with BMPR2 downregulation and progression of PAH. Here, we investigated for the first time the role of Switch-Independent 3a (SIN3a), a transcriptional regulator, in the epigenetic mechanisms underlying hypermethylation of BMPR2 in the pathogenesis of PAH. Methods: We used lung samples from PAH patients and non-PAH controls, preclinical mouse and rat PAH models, and human pulmonary arterial smooth muscle cells (hPASMC). Expression of SIN3a was modulated using a lentiviral vector or a siRNA in vitro and a specific Adeno-Associated Virus serotype 1 (AAV1) or a lentivirus encoding for human SIN3a in vivo . Results: SIN3a is a known transcriptional regulator; however, its role in cardiovascular diseases, especially PAH, is unknown. Interestingly, we detected a dysregulation of SIN3 expression in patients and in rodent models, which is strongly associated with decreased BMPR2 expression. SIN3a is known to regulate epigenetic changes. Therefore, we tested its role in the regulation of BMPR2 and found that BMPR2 is regulated by SIN3a. Interestingly, SIN3a overexpression inhibited hPASMC proliferation and upregulated BMPR2 expression by preventing the methylation of the BMPR2 promoter region. RNA sequencing analysis suggested that SIN3a downregulated the expression of DNA and histone methyltransferases such as DNMT1 and EZH2 while promoting the expression of the DNA demethylase TET1. Mechanistically, SIN3a promoted BMPR2 expression by decreasing CTCF binding to the BMPR2 promoter. Finally, we identified intratracheal delivery of AAV1.hSIN3a to be a beneficial therapeutic approach in PAH- by attenuating pulmonary vascular and RV remodeling, decreasing RVSP and mPAP pressure, and restoring BMPR2 expression in rodent models of PAH. Conclusions: Altogether, our study unveiled the protective/beneficial role of SIN3a in pulmonary hypertension. We also identified a novel and distinct molecular mechanism by which SIN3a regulates BMPR2 in hPASMC. Our study also identified lung-targeted SIN3a gene therapy using AAV1 as a new promising therapeutic strategy for treating patients with PAH.

The enterovirus Coxsackievirus B4 (CV-B4) can infect different human tissues and provoke abnormal function or destruction of various organs and cells. Moreover, its infections have been linked to the onset of type 1 diabetes. Coxsackievirus B4 is classified as a "challenging virus", due to the intense yet vain efforts to find effective prevention and therapeutic agents, especially within biological compounds. Lactobacillus plantarum is a lactic acid bacterium that is endowed with probiotic properties, and holds great potential for applications in medical and food industry sectors. Several compounds produced by this microorganism have been associated with various benefits including antimicrobial activity. In this work, we investigated the possible antiviral abilities of two Lb. plantarum strains and their derivatives against CV-B4. The different assays carried out (e.g. pre-incubation, competition and post-infection, using HEp-2 cells as human cell model) suggest that the tested microorganisms and their derivatives have an in vitro inhibiting activity against CV-B4. This is the first report showing the anti-CVB4 activity of Lb. plantarum strains and their derivatives.

Type B coxsackievirus (CV-B) infections are involved frequently in the triggering of several autoimmune diseases such as myocarditis, dilated cardiomyopathy, pericarditis, pancreatitis, type 1 diabetes, encephalitis, thyroiditis or Sjögren's syndrome. Serological and virological evidence suggests that maternal infections during pregnancy can play a role in the appearance of these diseases in offspring. The current study aims to explore the effect of an in-utero CV-B infection on the fetal thymus, the central site for programming immunological self-tolerance. In this perspective, female Swiss albino mice were inoculated intraperitoneally or orally with the diabetogenic CV-B4 E2 strain at gestational days 10 or 17. Offspring were killed at different post-inoculation times, and their thymuses were analysed for evidence of infection and alterations in thymic T cell subsets. In-utero CV-B infection of the thymus was demonstrated during the course of vertical transmission, as attested by viral RNA and infectious virus detection in most analysed samples. No histopathological changes were evident. Thymic T cells were not depleted, despite being positive for viral RNA. As evidenced by flow cytometry analysis, CV-B infection of the fetal thymus induced significant changes of thymic T cell populations, particularly with maternal inoculation at gestational day 10. Altogether, these findings suggest that CV-B infection of the fetal thymus may play an important role in the genesis of autoimmune diseases.