Gastrodin against oxidative stress-inflammation crosstalk via inhibiting mtDNA/TLR9 and JAK2/STAT3 signaling to ameliorate ischemic stroke injury.

The pathway of Janus-activated kinase 2 (JAK2) and signal transducer and activator of transcription 3 (STAT3) (termed as JAK2/STAT3) plays an active role in stroke-related inflammation induced by ischemic stress. Gastrodin, the primary compound in Gastrodia elata Bl, has been identified for its notable neuroprotective effects and demonstrated to ameliorate cerebral ischemia-reperfusion but its exact mechanisms governing this defense are still unclear. This study aims to investigate whether gastrodin can regulate mitochondrial function via the JAK2/STAT3 pathway to limit cerebral ischemia-reperfusion. In vivo, gastrodin significantly reduced infarct volume, improved neurobiological function, attenuated neuronal apoptosis, oxidative stress, mitochondrial impairment, mtDNA leakage, and inflammatory responses. At the cellular level, gastrodin administration rescued OGD/R-induced cell apoptosis, oxidative stress, and mitochondrial dysfunction. Mechanistically, gastrodin notably suppressed Toll-like receptor 9 (TLR9) expression, important for the recognition of disrupted endogenous DNA to produce inflammatory reactions. Furthermore, gastrodin mitigated inflammation by inhibiting JAK2/STAT3 signaling, influencing inflammatory factors to aggravate inflammation. Notably, the effects of gastrodin were abolished by Coumermycin A1 (C-A1), a JAK2 agonist, validating the role of JAK2/STAT3 signaling. In summary, gastrodin enhances the protective effect against mitochondrial damage in ischemic stroke by inhibiting JAK2/STAT3 signaling. Gastrodin is a possible therapy for cerebral ischemia.

Significance and considerations of establishing standardized critical values for critical size defects in animal models of bone tissue regeneration.

Establishing animal models with critical size defects (CSDs) is critical for conducting experimental investigations engineering of bone tissue regeneration. Currently, a standardised protocol for establishing an animal CSDs model has not been developed. Furthermore, a consensus has not been reached regarding the critical values of CSDs. Successful establishment of animal models for CSDs is a complex process that requires researchers to meticulously consider a variety of factors such as age, species, bone defect size and anatomic location. The specific numerical values for CSDs in small animal models vary, and a clear definition of the critical value for large animal CSDs models in the literature is still lacking. This review consolidates the advancements in critical bone defects animal models by outlining the research landscape across variables, including animal species, age groups, bone defect sites, and sizes, to offer valuable guidance and a theoretical framework for the establishment of pertinent experimental animal models.

Piceatannol protects against age-related hearing loss by inhibiting cellular pyroptosis and inflammation through regulated Caspase11-GSDMD pathway.

Age-related hearing loss (ARHL) is a common issue associated with aging. One of the typical causes of hearing loss is the damage to inner ear hair cells. In addition, oxidative stress and inflammation contribute to ARHL. To avoid excessive inflammatory responses, non-classical scorch death pathway by cell membrane lipopolysaccharide (LPS) activates of caspase-11. Piceatannol (PCT) is also known for anti-tumor, antioxidant and anti-inflammatory effects; however, the protective effect of piceatannol (PCT) on ARHL is unclear. The aim of this study was to elucidate the mechanism underlying protective effect of PCT on ARHL-induced inner ear hair cell damage. In vivo experiments showed that PCT could protect mice from inflammatory aging-induced hearing loss as well as from inner hair cells (IHC) and spiral ganglion (SG) deficits. In addition, inflammatory vesicle inhibitor BAY11-7082 ameliorated ARHL, inhibited NLRP3 and reduced GSDMD expression. In in vitro experiments we used LPS and D-gal to simulate the aging inflammatory environment. The results showed that intracellular reactive oxygen species levels, expression of Caspase-11, NLRP3, and GSDMD were significantly increased, yet treatment with PCT or BAY11-7082 significantly improved HEI-OC-1 cell injury while reducing inflammation-associated protein expression as well as the occurrence of pyroptosis. In conclusion, these results suggest a protective role for PCT against ARHL, possibly through Caspase-11-GSDMD pathway. Our findings may provide a new target and theoretical basis for hearing loss treatment using PCT.

CGF-HLC-I repaired the bone defect repair of the rabbits mandible through tight junction pathway.

Background: The human-like collagen I (HLC-I) combined concentrated growth factors was used to construct CGF-HLC-I composite biomaterials to repair the critical bone defect disease model of rabbit mandible. This study aimed to research the repair mechanism of CGF-HLC-I/Bio-Oss in rabbit mandibular critical bone defect, to provide a new treatment direction for clinical bone defect repair. Methods: The optimal concentration of HLC-I (0.75%) was selected in this study. Nine New Zealand white rabbits were randomly divided into 3 groups, normal control group, Bio-Gide/Bio-Oss and CGF-0.75%HLC-I/Bio-Oss group (n = 3, each group). CGF-0.75%HLC-I/Bio-Oss and Bio-Gide/Bio-Oss were implanted into rabbit mandibles, then X-ray, Micro-CT, HE and Masson staining, immunohistochemical staining and biomechanical testing were performed with the bone continuity or maturity at 4, 8 and 12 weeks after surgery. The repair mechanism was studied by bioinformatics experiments. Results: As the material degraded, the rate of new bone formation in the CGF-0.75% HLC-I/Bio-Oss group was better than that the control group by micro-CT. The biomechanical test showed that the compressive strength and elastic modulus of the CGF-0.75%HLC-I/Bio-Oss group were higher than those of the control group. HE and Masson staining showed that the bone continuity or maturity of the CGF-0.75%HLC-I/Bio-Oss group was better than that of the control group. Immunohistochemical staining showed significantly higher bone morphogenetic protein 2 (BMP2) and Runt-related transcription factor 2 (RUNX2) in the CGF-0.75%HLC-I/Bio-Oss group than the control group at 8 and 12 W and the difference gradually decreased with time. There were 131 differentially expressed proteins (DEPs) in the Bio-Gide/Bio-Oss and CGF-0.75%HLC-I/Bio-Oss groups, containing 95 up-regulated proteins and 36 down-regulated proteins. KEGG database enrichment analysis showed actinin alpha 1 (ACTN1) and myosin heavy-Chain 9 (MYH9) are the main potential differential proteins related to osteogenesis, and they are enriched in the TJs pathway. Conclusion: CGF-0.75%HLC-I/Bio-Oss materials are good biomaterials for bone regeneration which have strong osteoinductive activity. CGF-0.75%HLC-I/Bio-Oss materials can promote new bone formation, providing new ideas for the application of bone tissue engineering scaffold materials in oral clinics.

[microRNA-1 gene delivery mediated by exosomes suppresses CAL-27 cell proliferation].

OBJECTIVES: This study aims to construct endogenous exosomes abundantly loaded with miR-1 and investigate the role of exosome-mediated microRNA-1 (miR-1) delivery on CAL-27 cell proliferation. METHODS: Exosomes secreted by miR-1-overexpressing HEK293 cells (miR1-EXO) were purified via ultracentrifugation and subjected to transmission electron microscopy, nanoparticle analysis, Western blot analysis, and quantitative polymerase chain reaction (qPCR). CAL-27 cells were cocultured with exosomes secreted by HEK293 cells (CON-EXO) and miR1-EXO and equivalent phosphate buffer saline. The intracellular transport of exosomes was measured by using immunofluorescence, the expression of miR-1 and its target gene MET were investigated via qPCR, CAL-27 cell proliferation was measured through MTT assay, and cell cycle state was determined by applying flow cytometry. RESULTS: Electron microscopy revealed that miR1-EXO and CON-EXO were spherical or cup-shaped with an average diameter of approximately 110 nm. The well-known exosome markers CD9, Tsg101, and Alix were enriched. The expression of miR-1 in miR1-EXO was higher than that in CON-EXO (285.80±14.33 vs 1.00±0.06, P<0.000 1). After coculture with CAL-27 cells, miR1-EXO was internalized and unloaded miR-1 into CAL-27 cells. After coculture with miR1-EXO, the expression of miR-1 in CAL-27 cells was upregulated, whereas that of MET, the target gene of miR-1, was suppressed and the proliferation of CAL-27 cells was inhibited significantly. Normal oral keratinocyte cell proliferation was negligibly affected after coculture with miR1-EXO. CONCLUSIONS: Exosomes secreted from miR1-EXO cells could load abundant miR-1. Exosomal miR-1 delivered into CAL-27 cells by using miR1-EXO suppressed the expression of MET mRNA and inhibited cell proliferation.