Objective: This study aimed to elucidate the mechanisms underlying the impaired bone healing capacity in type 1 diabetes (T1DM) by investigating the role of the Hedgehog (Hh) signaling pathway in the impaired healing of cranial defects caused by T1DM. Methods: This study was approved by the experimental animal ethics committee of our hospital. A cranial defect model was established using Akita transgenic mice with spontaneous type I diabetes. The impact of T1DM on osteogenic differentiation and the Hh signaling pathway during cranial defect healing was explored by MicroCT scanning and immunohistochemical (IHC) analysis of osteocalcin (Ocn), Indian Hedgehog (Ihh), Patched1 (Ptch1), and zinc finger protein GLI1 (Gli1). Subsequently, the Hh signaling pathway was activated using smoothened agonist (SAG) (10 mg/kg, gavage), and its potential to improve cranial defect healing in T1DM was assessed by MicroCT and IHC staining. Finally, the ability of SAG (1 000 nmol/L) to counteract the inhibitory effects of a high-glucose environment (25 mol/L) on osteogenic differentiation of mouse bone marrow mesenchymal stem cells (BMSCs) was investigated through in vitro experiments. Detection methods included Alkaline Phosphatase and Alizarin Red staining, as well as quantitative real-time PCR (qPCR) analysis of the osteogenesis-related genes Alp, Spp1, Bglap, and Sp7. Results: Akita mice exhibited early, stable, and significant spontaneous T1DM characteristics. On postoperative day 21, the newly formed bone in the cranial defect area of Akita mice showed significant decreases in the bone volume-to-tissue volume ratio, volumetric bone mineral density, and Ocn expression (P < 0.05), with significant downregulation of Ihh, Ptch1, and Gli1 (P < 0.05). Activation of the Hh signaling pathway by SAG significantly mitigated the negative impact of T1DM on cranial defect healing in Akita mice (P < 0.05). Moreover, after SAG treatment, the inhibitory effects of the high-glucose environment on the alkaline phosphatase activity and in vitro mineralization capacity of BMSCs were significantly alleviated (P < 0.05), and the expression levels of osteogenic differentiation-related genes were significantly upregulated (P < 0.05). Conclusion T1DM inhibits cranial defect healing in Akita mice by suppressing the expression of the Hh signaling pathway, whereas activation of the Hh signaling pathway promotes osteogenesis and ameliorates the inhibitory effects of T1DM on bone healing.

Humans ; Gastrointestinal Microbiome ; Constipation/therapy* ; Probiotics/therapeutic use* ; Patients

BACKGROUND:The repair and clinical outcome of bone defects remains a hot and difficult area of clinical research,which is a common problem that plagues clinicians.Constructing suitable,reproducible and infinitely close to clinical animal experimental models and their scientific evaluation are essential for further clinical treatment of related diseases. OBJECTIVE:To retrospectively analyze the preparation methods and characteristics of common animal models of femoral bone defects and to assess their strengths and weaknesses,thereby providing some reference for relevant researchers to select appropriate animal models of femoral bone defects. METHODS:PubMed,Web of Science,Medline,and CNKI were retrieved for relevant literature published from January 1,2000 to August 1,2022.The keywords were"bone defect,bone,bones,defect,defects,defective,animal model,animal,model,laboratory,laboratory animal,animal laboratory"in English and"bone defect,animal model,experiment"in Chinese. RESULTS AND CONCLUSION:Twenty-seven randomized controlled animal experiments involving rats,mice,New Zealand rabbits,and sheep were included,analyzed and assessed.The most common types of bone defects were cylindrical bone defects and segmental osteotomy bone defects,generally found in the middle and distal femur.These models are mostly used to evaluate the effects of bone repair materials,drugs,drug-loaded active substances and physical therapy on bone defect repair and explore defect healing mechanisms,particularly the weight-bearing bone defect repair mechanism.Different defect kinds and femoral bone defect ranges have been found in different animal experiments.Researchers can select the suitable animal model and bone defect type based on the goal of the experiment and then set an acceptable bone defect value.Current studies have shown that cylindrical and segmental osteotomy-induced bone defects,mainly in the distal and middle femur,are mostly used in the animal models of femoral bone defects and that the surgical methods and postoperative management are more mature and operable to provide mature experimental animal models.In terms of cylindrical bone defects,rats and New Zealand rabbits are more suitable,whereas segmental osteotomy has no special requirements and all types of animals can meet the experimental requirements.

The people's police of public security organs shoulder the important mission of maintaining social security and stability, and ensuring the well-being of people. However, the working environment exposed to a variety of adverse factors has significantly increased the risk of cancer and cancer mortality of public security police, such as bladder cancer, prostate cancer, colon cancer, melanoma cancer, etc. Police related cancer risk research is a noteworthy issue. This article provides a review of existing research on the types and carcinogenic factors of cancer among domestic and foreign police officers, and analyzes various factors that may lead to their cancer based on the actual work situation of Chinese public security police. Corresponding response strategies are proposed to provide a scientific basis for reducing the risk of cancer among public security police.

Objective To explore the mechanism by which Sestrin2(SESN2)regulates autophagy activity of chondrocytes by mediating mammalian rapamycin target protein complex 1(mTORC1)signaling pathway.Methods The normal chondrocytes were treated with interleukin-1 β(IL-1β)to establish an osteoarthritis(OA)chondrocyte model,which was divided into the control group and the IL-1 β-treated group.Real-time quantitative PCR(qPCR)and Western blot were used to detect the expression levels of matrix metalloproteinase 13(MMP13),type Ⅱ collagen(COL2A1)and SESN2 in the two groups.The cell models of the chondrocyte overexpression SESN2 group and knockdown SESN2 group were obtained via cell transfection technology,and the expression levels of SESN2 in each group were detected by qPCR while those of SESN2,MMP13,COL2A1,mTORC1 pathway-related proteins and autophagy-related proteins in each group were detected by Western blot.The effects of SESN2 on cell proliferation and migration were detected by CCK-8 and cell scratch assay.Results(1)The expression level of MMP13 in the IL-1 β-treated group was significantly up-regulated,while the expression levels of COL2A1 and SESN2 were significantly decreased.(2)Compared with the control group,the expressions of p-mTORC1,ribosomal protein S6 kinase 1(S6K1),and MMP13 protein in OA chondrocytes in the overexpression group were significantly down-regulated,while the expressions of adenosine 5'-monophosphate(AMP)-activated protein kinase(AMPK)and chondroprotective gene COL2A1 were significantly increased,and the expression level of Beclin-1 and the ratio of microtubule associated protein 1 light chain 3-Ⅱ(LC3-Ⅱ)/(LC3-Ⅰ)were increased.Meanwhile,overexpression of SESN2 could up-regulate the proliferation and migration of chondrocytes,but the results were opposite after knockdown of SESN2.Conclusion SESN2 can enhance autophagy,proliferation and migration of chondrocytes by inhibiting mTORC1 pathway,which has provided data for revealing the pathogenesis of OA and exploring new therapeutic methods.