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Biology subjects

Zhang, l.

Publications and source records attributed to Zhang, l..

4 recordsLinked to original sources

Curcumin attenuates microglia-mediated chronic neuropathic pain through CDK5 /p35 signaling pathway

Curcumin is a phenolic compound derived from turmeric, one of the main ingredients of curry powder, which is widely used for its antioxidant, anti-inflammatory and immunomodulatory effects. Curcumin has been reported to help relieve pain, such as neuropathic pain caused by injury or disease, but the specific mechanism of its antinociceptive effect on pathological pain is unclear. Cyclin-dependent kinase 5 (Cdk5) is a key control point for the release of neurotransmitters from presynaptic vesicles. Cdk5 and its activator p35 couple to regulate key signaling cascades, thereby participating in the pain process. In this study, we established a NP model by chronic constriction injury (CCI) of the bilateral sciatic nerve in rats and evaluated behavioral hyperalgesia using mechanical and hot and cold tests. Protein expression and distribution were evaluated using western blotting and immunofluorescence. The results showed that Iba-1 and Cdk5/p35 were co-localized in the dorsal horn and dorsal root ganglia, respectively. After CCI, the expression of Cdk5 and p35 was upregulated in the dorsal horn and dorsal root ganglia, while intraperitoneal injection of curcumin significantly reversed the activation of Cdk5/p35 protein and alleviated the hyperalgesia in rats. In addition, the injection of curcumin reduced the co-localization expression of Iba-1 and Cdk5/p35, indicating that curcumin inhibited the activation of Cdk5/p35 protein in the dorsal horn and dorsal root ganglia, thereby affecting the activation of microglia, thereby having a destructive effect on the neuronal cell plasticity and synaptic structure remodeling in the development of NP. Our study provides new evidence that Cdk5/p35 in the dorsal horn and dorsal root ganglia is related to the occurrence of NP, introduces microglia as the basis for the long-term maintenance of NP, and provides insights into the molecular mechanisms involved in the analgesic effect of curcumin. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=188 SRC="FIGDIR/small/623498v1_ufig1.gif" ALT="Figure 1"> View larger version (80K): org.highwire.dtl.DTLVardef@125fc20org.highwire.dtl.DTLVardef@cba7d3org.highwire.dtl.DTLVardef@772291org.highwire.dtl.DTLVardef@17e87e3_HPS_FORMAT_FIGEXP M_FIG C_FIG

neuroscience↗

Dehydrozaluzanin C- derivative protects septic mice by alleviating over-activated inflammatory response and promotes the phagocytosis of macrophages

Host-directed therapy (HDT) is a new adjuvant strategy that interfere with host cell factors that are required by a pathogen for replication or persistence. In this study, we assessed the effect of dehydrozaluzanin C-derivative (DHZD), a modified compound from dehydrozaluzanin C (DHZC), as a potential HDT agent for severe infection. LPS-induced septic mouse model and Carbapenem resistant Klebsiella pneumoniae (CRKP) infection mouse model was used for testing in vivo. RAW264.7 cells, mouse primary macrophages, and DCs were used for in vitro experiments. Dexamethasone (DXM) was used as a positive control agent. DHZD ameliorated tissue damage (lung, kidney, and liver) and excessive inflammatory response induced by LPS or CRKP infection in mice. Also, DHZD improved the hypothermic symptoms of acute peritonitis induced by CRKP, inhibited heat-killed CRKP (HK-CRKP)-induced inflammatory response in macrophages, and upregulated the proportions of phagocytic cell types in lungs. In vitro data suggested that DHZD decreases LPS-stimulated expression of IL-6, TNF- and MCP-1 via PI3K/Akt/p70S6K signaling pathway in macrophages. Interestingly, the combined treatment group of DXM and DHZD had a higher survival rate and lower level of IL-6 than those of the DXM-treated group; the combination of DHZD and DXM played a synergistic role in decreasing IL-6 secretion in sera. Moreover, the phagocytic receptor CD36 was increased by DHZD in macrophages, which was accompanied by increased bacterial phagocytosis in a clathrin- and actin-dependent manner. This data suggests that DHZD may be a potential drug candidate for treating bacterial infections.

pathology↗

An atypical endomembrane localized CNL-type immune receptor with a conserved deletion in the N-terminal signaling domain functions in cell death and immunity

Plants have evolved intracellular nucleotide-binding leucine rich repeat receptors (NLRs) to induce a superior immune response. Upon activation, coiled-coil (CC) domain containing NLRs (CNLs) oligomerize to form apparent cation channels that promote calcium influx and cell death induction, with the alpha-1 helix of the individual CC domains penetrating membranes. Some members of a monophyletic subclass of CNLs, the ancient and autonomous NLRs (ANLs), are characterized by putative N- myristoylation and S-acylation sites at the N-terminus of their CCG10/GA domain, potentially mediating permanent membrane association. Whether these Potentially Membrane Localized NLRs (PMLs) mediate cell death upon activation in a similar way as reported for other CNLs has been unknown. We integrated phylogenetic, cell- biological, and functional studies to uncover the cell death function of an atypical but conserved Arabidopsis PML, PML5, which has a 113 amino acid deletion in its CCG10/GA domain. Active PML5 oligomers localize in Golgi membranes and the tonoplast, changes vacuolar morphology, and induce cell death, with the short N- terminus being sufficient for cell death. Mutant analysis supports a potential key role of PMLs in plant immunity. Similar deletions as in Arabidopsis PML5 are found in several Brassicales paralogs, pointing to the evolutionary importance of this innovation. PML5 is thus a naturally occurring CNL variant with a minimal signaling domain and its further study should help in understanding the functional importance of this minimal domain for NLR signaling.

plant biology↗

The marine natural microbiome mediates physiological outcomes in host nematodes

Nematodes are the most abundant metazoans in marine sediments, many of which are bacterivores, however how habitat bacteria effects physiological outcomes in marine nematodes remains largely unknown. Here, we used a Litoditis marina inbred line to assess how native bacteria modulates host nematode physiology. We characterized seasonal dynamic bacterial compositions in L. marina habitats, and examined the impacts of 448 habitat bacteria isolates on L. marina development, then focused on HQbiome with 73 native bacteria, of which we generated 72 whole genomes sequences. Unexpectedly, we found that the effects of marine native bacteria on the development of L. marina and its terrestrial relative Caenorhabditis elegans were significantly positively correlated. Next, we reconstructed bacterial metabolic networks and identified several bacterial metabolic pathways positively correlated with L. marina development (e.g., ubiquinol and heme b biosynthesis), while pyridoxal 5-phosphate biosynthesis pathway was negatively associated. Through single metabolite supplementation, we verified CoQ10, heme b, Acetyl-CoA, and acetaldehyde promoted L. marina development, while vitamin B6 attenuated growth. Notably, we found that only four development correlated metabolic pathways were shared between L. marina and C. elegans. Furthermore, we identified two bacterial metabolic pathways correlated with L. marina lifespan, while a distinct one in C. elegans. Strikingly, we found that glycerol supplementation significantly extended L. marina but not C. elegans longevity. Moreover, we comparatively demonstrated the distinct gut microbiota characteristics and their effects on L. marina and C. elegans physiology. Our integrative approach will provide a microbe-nematodes framework for microbiome mediated effects on host animal fitness.

microbiology↗