Alpha-kinase1 promotes tubular injury and interstitial inflammation in diabetic nephropathy by canonical pyroptosis pathway

BACKGROUND: Alpha-kinase 1 (ALPK1) is a master regulator in inflammation and has been proved to promote renal fibrosis by promoting the production of IL-1ß in diabetic nephropathy (DN) mice. Pyroptosis is involved in high glucose (HG)-induced tubular cells injury, characterized by activation of Gasdermin D (GSDMD) and the release of IL-1ß and IL-18, resulting in inflammatory injury in DN. It is reasonable to assume that ALPK1 is involved in pyroptosis-related tubular injury in DN. However, the mechanism remains poorly defined. METHODS: Immunohistochemistry (IHC) staining was performed to detect the expression of pyroptosis- and fibrosis-related proteins in renal sections of DN patients and DN mice. DN models were induced through injection of streptozotocin combined with a high-fat diet. Protein levels of ALPK1, NF-κB, Caspase-1, GSDMD, IL-1ß, IL-18 and α-SMA were detected by Western blot. HK-2 cells treated with high-glucose (HG) served as an in vitro model. ALPK1 small interfering RNA (siRNA) was transfected into HK-2 cells to down-regulate ALPK1. The pyroptosis rates were determined by flow cytometry. The concentrations of IL-1ß and IL-18 were evaluated by ELISA kits. Immunofluorescence staining was used to observe translocation of NF-κB and GSDMD. RESULTS: The heat map of differentially expressed genes showed that ALPK1, Caspase-1 and GSDMD were upregulated in the DN group. The expression levels of ALPK1, Caspase-1, GSDMD and CD68 were increased in renal biopsy tissues of DN patients by IHC. ALPK1expression and CD68+ macrophages were positively correlated with tubular injury in DN patients. Western blot analysis showed increased expressions of ALPK1, phospho-NF-κB P65, GSDMD-NT, and IL-1ß in renal tissues of DN mice and HK-2 cells, accompanied with increased renal fibrosis-related proteins (FN, α-SMA) and macrophages infiltration in interstitial areas. Inhibition of ALPK1 attenuated HG-induced upregulation expressions of NF-κB, pyroptosis-related proteins Caspase-1, GSDMD-NT, IL-1ß, IL-18, α-SMA, and pyroptosis level in HK-2 cells. Also, the intensity and nuclear translocation of NF-κB and membranous translocation of GSDMD were ameliorated in HG-treated HK-2 cells after treatment with ALPK1 siRNA. CONCLUSIONS: Our data suggest that ALPK1/NF-κB pathway initiated canonical caspase-1-GSDMD pyroptosis pathway, resulting in tubular injury and interstitial inflammation of DN.

Application of digital design combined with 3D-printing technologies in dental autotransplantation / 口腔疾病防治

Objective@#To evaluate the therapeutic effect of dental autotransplantation with the application of digital design combined with 3D printing of donor tooth models and recipient alveolar fossa model preoperatively.@*Methods@# Twelve cases that could not be retained due to tooth fracture or extensive absorption of alveolar bone were recruited in the study. Cone-beam computed tomography (CBCT) data were imported into Mimics software for digital design, and the best-matched third molar was selected as the donor tooth. Replicas of the donor teeth and the recipient socket were printed out with three-dimensional (3D) printing technologies as a simulation model for recipient tooth socket preparation. During tooth autotransplantation, preparation of the recipient tooth socket and the donor tooth were guided by the 3D-printed replicas sequentially. Then, the donor tooth was implanted into the recipient tooth pocket. Patients were followed up at 3, 6 and 12 months after the operation, with CBCT examination to evaluate the status of bone reconstruction and periodontal ligaments at each time point. @*Results@#Twelve patients were transplanted with an autogenous third molar with the apical foramen completely closed. Among them, 7 patients had alveolar fossa infection before the operation, of which 1 had extensive resorption of the alveolar bone due to the infection. All 12 patients recovered well after the operation and were followed up for at least 12 months. In total, 11 caseswere successful in tooth autotransplantation with normal mastication, and 1 case had root resorption 14 months postoperation.@*Conclusion@#Digital design combined with 3D printing technology can assistin the selection of thebest-matched donor tooth and preparation of the recipient socket before tooth transplantation proceduresand reduce the extra-alveolar exposure time of the donor tooth and number of trial placementsintothe alveolar fossa. Thus, this combined strategy can effectively improve the outcome of dental autotransplantation.

The expression of filaggrin in oral submucosal fibrosis / 口腔疾病防治

Objective@#To study the expression and distribution of filaggrin (FLG) in oral submucous fibrosis (OSF) and to explore the significance of FLG in the occurrence and development of OSF.@*Methods @#Ten cases with a normal oral mucosa (normal buccal mucosa group) and 30 cases of tissues with OSF lesions, including 10 cases each in the early (early OSF group), moderate (middle OSF group) and advanced stages (late OSF group), were selected. FLG was analyzed by immunohistochemistry. The FLG-positive cells were counted to calculate the percentages of cells with FLG-positive expression in each group.@*Results@#FLG expression was negative in most of the normal buccal mucosa group specimens and was positive in the OSF buccal mucosal epithelial specimens. With aggravation of the OSF lesion, the number of FLG-positive cells increased. In the early OSF group, FLG-positive expression was mainly concentrated in the granular and keratinized epithelial layers. In the middle OSF group, the number of FLG-positive epithelial cells increased gradually. In the late OSF group, almost all epithelial cells were FLG-positive in the cytoplasmic nucleus. The percentages of FLG-positive cells in the early, middle and late OSF groups were (24.63 ± 9.06)%, (54.23 ± 10.63)% and (83.97 ± 8.72)%, respectively. The percentage of FLG-positive cells was significantly higher in the OSF group than in the normal mucosa group (P < 0.05).@*Conclusion@#FLG was expressed at a higher level in the OSF epithelium than in the normal oral mucosal epithelium and was upregulated in the OSF epithelium with aggravation of the OSF lesions. Abnormal FLG expression may be related to the terminal differentiation disorder of OSF epithelial keratinocytes.