Vitronectin Regulates the Fibrinolytic System during the Repair of Cerebral Cortex in Stab-Wounded Mice

2-Carba cyclic phosphatidic acid regulates blood coagulation and fibrinolysis system for repair after brain injury

Effective blood coagulation prevents inflammation and neuronal loss after brain injury. 2-Carba-cyclic phosphatidic acid (2ccPA), a biotherapeutic for brain injury, inhibits blood extravasation resulting from blood-brain barrier breakdown. However, the hemostasis mechanism of 2ccPA remains unclear. We determined the effects of 2ccPA-injection on blood coagulation and fibrinolysis using a needle-induced brain injury model. 2ccPA suppressed the expression of platelet degranulation-related genes. Immediately after brain injury, 2ccPA increased CD41+ platelet aggregation around the lesions and promoted fibrin aggregation. Additionally, 2ccPA supported fibrinolysis by upregulating plasminogen activator expression. These results suggest the acute effects of 2ccPA on brain hemostasis.

Extracellular matrix influences astrocytic extracellular vesicle function in wound repair

Astrocytic injury responses are known to be influenced by the extracellular matrix (ECM). Astrocytes are also recognized as a source of extracellular vesicles (EVs) that can impact the activity and function of other astrocytes and cell types. Whether the ECM influences the function of astrocytic EVs in the context of wound recovery has not been previously studied. We report EVs from astrocytes cultured on varied ECM substrates are sufficient to elicit distinct injury responses in naive astrocytes that recapitulate the effects of the ECM of origin. When compared with wound recovery on control substrates, EVs from ECM-exposed astrocytes elicited accelerated rates of wound recovery that varied based on each ECM. When EVs were collected from IL-1β treated and ECM-exposed astrocyte cultures, we found that IL-1β arrested wound recovery in naive astrocytes treated with EVs from astrocytes cultured on ECM but adding EVs from IL-1β treated Tenascin-c-cultured astrocytes increased wound recovery. To confirm that ECM was a primary influence on these astrocytic EV functions, we tested the contribution of β1-integrin, a major integrin receptor for the ECM molecules tested in this study. We found that the β1-integrin inhibitor Ha2/5, resulted in EVs that significantly attenuated the wound recovery of naive astrocytes. This provides new information on the importance of culture substrates on astrocytic responses, EV functions and injury responses that may impact the understanding of astroglial responses related to ECM compositional differences in diverse physiological states.

Role of Autophagy Biomarkers In Burn-Age Estimation and Progression

BACKGROUND

Determination of time passed since burn injury in the living is critical in forensic science. Autophagy biomarkers and vitronectin can play an important role in determination of the age of burn injuries through their levels in the tissue.

OBJECTIVE

The aim of this study was to investigate the role of autophagy biomarkers in dating burn injury and to correlate them with the histopathological effects of deep second-degree thermal burn.

METHOD

Fifty-four male rats were used in this study after infliction of second-degree thermal burns to their skin. Samples were taken from them after 30 minutes and one, four, 24, 48, and 72 hours following burn to be examined histologically and also for autophagy biomarkers and vitronectin.

RESULTS

Significant reduction in the autophagy biomarkers (p < 0.001) over the first 24 hours then began to increase but still not reach the normal level up to 72 hours after burn. Vitronectin level increased after burn infliction 1.5-fold after first hour, then up to four-fold after four hours and after that began to decline but still did not reach the normal level up to 72 hours.

CONCLUSION

Autophagy biomarkers can be used as a forensic tool in determination of the time passed since burn infliction in living.

Investigating the Proteomic Profile of HT-29 Colon Cancer Cells After Lactobacillus kefiri SGL 13 Exposure Using the SWATH Method

Despite some studies revealed that kefir acts on different cancers, such as colorectal cancer, the proteomic changes that occur in the colon cancer cells remain to be explored. In this study, the proteomic analysis was combined with determination of kefir characteristics (e.g., adhesion capacity, gastrointestinal and antibiotic resistances), in order to confirm its use as a probiotic. Therefore, a label-free strategy based on SWATH-MS was applied to investigate the proteomic profile of HT-29 cells after exposure for 24 h to a specific strain of Lactobacillus kefiri named SGL 13. We identified a total of 60 differentially expressed proteins in HT-29 cells, among which most are located into the extracellular exosome, playing important/crucial roles in translation and cell adhesion, as indicated by the enrichment analysis. The eIF2 and retinoid X receptor activation pathways appeared to be correlated with the anti-tumoral effect of SGL 13. Immunoblot analysis showed an increase in Bax and a decrease in caspase 3 and mutant p53, and ELISA assay revealed inhibition of IL-8 secretion from HT-29 cells stimulated with LPS upon SGL 13 treatment, suggesting pro-apoptotic and anti-inflammatory properties of kefir. In conclusion, the results of this study, the first of its kind using co-culture of kefir and colon cancer cells, demonstrate that L. kefiri SGL 13 possesses probiotic potency and contribute to elucidate the molecular mechanisms involved in the L. kefiri-colon cancer cell interactions.

Vitronectin deficiency attenuates hepatic fibrosis in a non-alcoholic steatohepatitis-induced mouse model

Vitronectin (VN), an extracellular matrix protein, is a promising immune biomarker of non-alcoholic steatohepatitis (NASH); however, its precise function remains unclear. This study investigated how VN deficiency contributes to the development of NASH. Towards this aim, wild-type (WT) and VN-/- mice were fed with a choline-deficient, L-amino acid-defined, high-fat diet (CDAHFD) for 6 and 10 weeks to induce NASH, and the livers were isolated. In WT mice fed with CDAHFD for 6 and 10 weeks, the expression of Vn mRNA and protein was up-regulated compared with that in mice fed with the MF control diet, indicating that VN is regulated in NASH condition. VN-/- mice showed decreased picrosirius red staining in the liver area and Col1a2 mRNA expression levels, compared with WT mice, indicating that the severity of hepatic fibrosis is attenuated in the CDAHFD-fed VN-/- mice. In addition, VN deficiency did not affect the area of lipid droplets in haematoxylin-eosin staining and the mRNA expression levels of fatty acid synthases, Srebp, Acc and Fas in the CDAHFD-fed mice. Moreover, VN deficiency decreased the inflammation score and the mRNA expression levels of Cd11b and F4/80, macrophage markers, as well as Tnf-α and Il-1β, inflammatory cytokines in the CDAHFD-fed mice. Furthermore, VN deficiency decreased the protein and mRNA expression levels of α-smooth muscle actin in the CDAHFD-fed mice, suggesting that VN deficiency inhibits the activation of hepatic stellate cells (HSCs). Our findings indicate that VN contributes to the development of fibrosis in the NASH model mice via modulation of the inflammatory reaction and activation of HSCs.

2-carba cyclic phosphatidic acid suppresses inflammation via regulation of microglial polarisation in the stab-wounded mouse cerebral cortex

Traumatic brain injury (TBI) is caused by physical damage to the brain and it induces blood-brain barrier (BBB) breakdown and inflammation. To diminish the sequelae of TBI, it is important to decrease haemorrhage and alleviate inflammation. In this study, we aimed to determine the effects of 2-carba-cyclic phosphatidic acid (2ccPA) on the repair mechanisms after a stab wound injury as a murine TBI model. The administration of 2ccPA suppressed serum immunoglobulin extravasation after the injury. To elucidate the effects of 2ccPA on inflammation resulting from TBI, we analysed the mRNA expression of inflammatory cytokines. We found that 2ccPA prevents a TBI-induced increase in the mRNA expression of Il-1β, Il-6, Tnf-α and Tgf-β1. In addition, 2ccPA reduces the elevation of Iba1 levels. These data suggest that 2ccPA attenuates the inflammation after a stab wound injury via the modulation of pro-inflammatory cytokines release from microglial cells. Therefore, we focused on the function of 2ccPA in microglial polarisation towards M1 or M2 phenotypes. The administration of 2ccPA decreased the number of M1 and increased the number of M2 type microglial cells, indicating that 2ccPA modulates the microglial polarisation and shifts them towards M2 phenotype. These data suggest that 2ccPA treatment suppresses the extent of BBB breakdown and inflammation after TBI.