Hydrogen-rich saline regulates NLRP3 inflammasome activation in sepsis-associated encephalopathy rat model.

Sepsis-associated encephalopathy (SAE) is characterised by long-term cognitive impairment and psychiatric illness in sepsis survivors, associated with increased morbidity and mortality. There is a lack of effective therapeutics for SAE. Molecular hydrogen (H2) plays multiple roles in septic diseases by regulating neuroinflammation, reducing oxidative stress parameters, regulating signalling pathways, improving mitochondrial dysfunction, and regulating astrocyte and microglia activation. Here we report the protective effect of hydrogen-rich saline in the juvenile SAE rat model and its possible underlying mechanisms. Rats were injected intraperitoneally with lipopolysaccharide at a dose of 5 mg/kg to induce sepsis; Hydrogen-rich saline (HRS) was administered 1 h after LPS induction at a dose of 5 ml/kg and nigericin at 1 mg/kg 1 h before LPS injection. H&E staining for neuronal damage, TUNEL assay for detection of apoptotic cells, immunofluorescence, ELISA protocol for inflammatory cytokines and 8-OHdG determination and western blot analysis to determine the effect of HRS in LPS-induced septic rats. Rats treated with HRS showed decreased TNF-α and IL-1ß expression levels. HRS treatment enhanced the activities of antioxidant enzymes (SOD, CAT and GPX) and decreased MDA and MPO activities. The number of MMP-9 and NLRP3 positive immunoreactivity cells decreased in the HRS-treated group. Subsequently, GFAP, IBA-1 and CD86 immunoreactivity were reduced, and CD206 increased after HRS treatment. 8-OHdG expression was decreased in the HRS-treated rats. Western blot analysis showed decreased NLRP3, ASC, caspase-1, MMP-2/9, TLR4 and Bax protein levels after HRS treatment, while Bcl-2 expression increased after HRS treatment. These data demonstrated that HRS attenuated neuroinflammation, NLRP3 inflammasome activation, neuronal injury, and mitochondrial damage via NLRP3/Caspase-1/TLR4 signalling in the juvenile rat model, making it a potential therapeutic agent in the treatment of paediatric SAE.

The Effect of Wnt Family Member 5a Gene Silencing on the Proliferation of Achondroplasia Using a DNAzymes-CoOOH Nanocomposite.

Achondroplasia is a kind of congenital dysplasia due to the defect of endochondral ossification. Achondroplasia is considered to be a protein folding disease leading to endoplasmic reticulum stress. Endoplasmic reticulum stress may lead to disease by affecting the function and survival state of chondrocytes, but the specific mechanism requires further study. In this study, bioinformatics methods, online database mining, screening of differentially expressed genes for pathway enrichment, and interaction analysis were conducted to detect the Wnt family member 5a (Wnt5a) gene. Additionally, we designed a novel DNAzymes-based nanocomposite that can simultaneously silence Wnt5a genes in chondrocytes. The nanocomposite was composed of amino-functionalized cobalt oxyhydroxide nanoflakes modified by DNAzymes that target the Wnt5a gene. Further, we conducted in vitro experiments to verify that Wnt5a can mediate the mitogen-activated protein kinase signaling pathway through the endoplasmic reticulum stress pathway to affect the proliferation of chondrocytes.

Existence of Th22 in children and evaluation of IL-22 + CD4 + T, Th17, and other T cell effector subsets from healthy children compared to adults.

BACKGROUND: Children are prone to get infections, especially in the respiratory system and the gut mainly because their immune system is immature. T cells significantly contribute to the prevention of infections, and different helper T cell (Th) subsets play different anti-pathogen roles. Interleukin (IL)-22 producing by T-helper 22 cells (Th22) play an important role in host defense against Gram-negative bacterial organisms in gut and lung. T-helper 17 cells (Th17) protect against extracelluar bacteria and fungi especially at the epithelial surface. However, there is no report comparing IL-22 producing T cells and Th17 cells in healthy young children to adults. METHODS: Flow cytometry (FCM) was used to observe whether Th22 subset existed in the peripheral blood of healthy young children. Meanwhile, we determined the frequencies of Th subsets including Th17, Th1 and Th2, cytotoxic T (Tc)1 subset, CD4+ and CD8+ memory T cells in the peripheral blood of both young children and adults. RESULTS: In the present study, we demonstrated that Th22 subset existed in peripheral blood of children, with IL-22 mainly secreted by CD4 + CD45RO+ memory T cells. Moreover, we observed that IL-22 + CD4 + T cells and Th subsets including Th17, Th1, and Th2 frequencies of young children (1-6 years old) were significantly lower than adults. While the Th1 frequency from Group A (1-3 years old) was markedly lower than that from Group B (4-6 years old). No significant differences of Th17 or IL-22 + CD4 + T cells frequencies were observed between these two groups. In addition, Tc1 subset frequencies were also remarkably lower in young children than in adults. Furthermore, lower frequencies of CD45RO+ memory CD4+ and CD8+ T cells in young children than in adults, and significant correlation between CD45RO+ memory CD4 + T cells and IL-22 + CD4 + T cells, Th1, Th17 were observed. CONCLUSIONS: Th22 subset exists in the peripheral blood of young children. Compared with adults, there are lower frequencies of IL-22 + CD4 + T cells, as well as Th1, Th17, Th2 and Tc1 subsets in the peripheral blood of young children.