Association between serum calcium level and type 2 diabetes: An NHANES analysis and Mendelian randomization study.

AIMS: This study investigated the association between serum calcium levels and the prevalence of T2D using a cross-sectional study and Mendelian randomization analysis. METHODS: Cross-sectional data were obtained from the National Health and Nutrition Examination Survey (NHANES) from 1999 to 2018. Serum calcium levels were divided into three groups (low, medium and high groups) according to the tertiles. Logistic regression was used to estimate the association between serum calcium levels and T2D prevalence. Instrumental variables for serum calcium levels were obtained from the UK Biobank and a two-sample MR analysis was performed to examine the causal relationship between genetically predicted serum calcium levels and the risk of T2D. RESULTS: A total of 39,645 participants were available for cross-sectional analysis. After adjusting for covariates, participants in the high serum calcium group had significantly higher odds of T2D (OR = 1.18, 95% CI = 1.07, 1.30, p = 0.001) than those in the moderate group. Restricted cubic spline plots showed a J-shaped curve relationship between serum calcium level and prevalence of T2D. Consistently, Mendelian randomization analysis showed that higher genetically predicted serum calcium levels were causally associated with a higher risk of T2D (OR = 1.16, 95% CI: 1.01, 1.33, p = 0.031). CONCLUSIONS: The results of this study suggest that higher serum calcium levels are causally associated with a higher risk of T2D. Further studies are needed to clarify whether intervening in high serum calcium could reduce the risk of T2D.

The Nrf2/HMGB1/NF-κB axis modulates chondrocyte apoptosis and extracellular matrix degradation in osteoarthritis.

Osteoarthritis (OA) is a degenerative or posttraumatic condition of the joints. In OA chondrocytes, Nrf2 functions as a stress response regulator with antioxidant and anti-inflammatory effects. This study aims to investigate the role of Nrf2 and its downstream pathway in the development of osteoarthritis. IL-1ß treatment suppresses Nrf2, aggrecan, and COL2A1 levels and cell viability but promotes apoptosis in chondrocytes. IL-1ß stimulation induces cell apoptosis, upregulates the mRNA expression of inflammatory factors, decreases aggrecan, COL2A1, and Bcl-2 levels but increases ADAMTS-5, ADAMTS-4, MMP13, cleaved caspase 3, and BAX levels, and promotes p65 phosphorylation. Nrf2 overexpression exerts opposite effects on IL-1ß-treated chondrocytes, as demonstrated by the significant attenuation of IL-1ß-induced changes in chondrocytes. By binding to the HMGB1 promoter region, Nrf2 suppresses HMGB1 expression. Similar to Nrf2 overexpression, HMGB1 knockdown also attenuates IL-1ß-induced changes in chondrocytes. Notably, under IL-1ß stimulation, the effects of Nrf2 overexpression or tert-butylhydroquinone (TBHQ, an activator of Nrf2) on apoptosis, inflammatory factor expression, ECM and apoptosis, and NF-κB pathway activity in chondrocytes are remarkably reversed by HMGB1 overexpression or recombinant HMGB1 (rHMGB1). Similarly, rHMGB1 could partially counteract the curative effect of TBHQ on OA damage in mice. In OA cartilage tissue samples, the level of Nrf2 is lower, while the levels of HMGB1, apoptotic, and inflammatory factors are increased compared to normal cartilage tissue samples. In conclusion, for the first time, the Nrf2/HMGB1 axis was found to modulate apoptosis, ECM degradation, inflammation and activation of NF-κB signaling in chondrocytes and OA mice.

Cissus quadrangularis L extract-loaded tricalcium phosphate reinforced natural polymer composite for guided bone regeneration.

Natural medicines plants are significant considerable attention as potential therapeutic agents for bone tissue engineering. Cissus quadrangularis L (CQ). is a potent therapeutic plant known for its own osteogenic properties. In this research work, a phytoconstituents-filled composite was produced by incorporating CQ extract with gelatin (Gel) and pectin (Pec) polymers collective through ß- tricalcium phosphate (ß-TCP) bioceramic via a green template method. The effect of CQ-filled composite morphology and chemical structural properties, in vitro cytotoxicity, cell proliferation, and differentiation was investigated. FTIR spectroscopic results indicated the prepared materials' structural confirmation. The CQ extract was the alcoholic -OH merge with the hydroxyl and -NH groups in the range of 3000 cm-1 to 3500 cm-1. Scanning electron microscopy images showed that the ß-TCP ceramic was perfectly embedded in Gel-Pec polymeric matrix, which is important for bone regeneration. In vitro cell culture results indicated that ß-TCP/Gel-Pec/CQ composite provided 92.0% of a favorable substrate for mesenchymal stem cell viability. The gene expression and RT-PCR studies represent the materials with good osteogenic expression, especially the ß-TCP/Gel-Pec/CQ composite is observed at 168.0% and 188.0% for RUNx2 and OCN, respectively. The result of the physicochemical characterizations and cell viability studies suggest that CQ-loaded ß-TCP/Gel-Pec composite can serve as a potential biomaterial for bone tissue repair and regeneration.

Arthroscopic anterior talofibular ligament repair with Internal Brace and lasso-loop technique for chronic ankle lateral instability.

OBJECTIVE: To introduce the surgical technique and clinical outcomes of arthroscopic anterior talofibular ligament (ATFL) repair using the Internal Brace and lasso-loop technique for chronic ankle lateral instability. METHODS: A retrospective study was performed on 29 patients who underwent all-arthroscopic ATFL repair with the Internal Brace and lasso-loop technique from January to August 2020. The patients included 24 males and five females, with a mean age of 30.17 years. Through the accessory anterolateral (AAL) portal, we drilled the bone tunnels and fixed the tape with 4.75 mm and 3.5 mm "SwiveLock" anchors and reattached the torn ligament by the lasso-loop technique. RESULTS: All 29 patients underwent all-arthroscopic procedures smoothly without serious complications, such as infection and important nerve or vessel injuries. There were eight cases of lateral malleolar avulsion fractures and ten cases of talus cartilage injury. The visual analog scale (VAS), Karlsson-Peterson, Tegner, and American Orthopedic Foot and Ankle Society (AOFAS) scores were used to evaluate the clinical consequences. All the patients were followed up for 18.66 ± 4.85 months on average. The average pre-operative VAS score was 4.69 ± 1.04, which was significantly higher than the average post-operative VAS score of 1.14 ± 1.56. At the final follow-up appointments, the averages of Karlsson-Peterson, AOFAS, and Tenger scores were 75.83 ± 9.44, 88.31 ± 6.81, and 6.93 ± 1.79, respectively, which was significantly higher than that before the operation. CONCLUSION: This arthroscopic anterior talofibular ligament repair with the Internal Brace and lasso-loop technique achieves satisfactory clinical outcomes with the benefits of high safety and reliability for chronic ankle lateral instability.

MiR-181a-5p promotes osteogenesis by targeting BMP3.

High-throughput microRNA (miRNA) sequencing of osteoporosis was analyzed from the Gene Expression Omnibus (GEO) database to investigate specific microRNAs that control osteogenesis. MiR-181a-5p was differentially expressed among healthy subjects and those with osteoporosis. Inhibitors and mimics were transfected into cells to modulate miR-181a-5p levels to examine the role in MC3T3-E1 functions. Alkaline phosphatase (ALP) staining and Alizarin Red S (ARS) staining were used for morphological detection, and proteins of ALP and Runt-related transcription factor 2 (RUNX2), as osteogenesis markers, were detected. During the osteogenic differentiation of MC3T3-E1, the transcription level of miR-181a-5p was significantly increased. The inhibition of miR-181a-5p suppressed MC3T3-E1 osteogenic differentiation, whereas its overexpression functioned oppositely. Consistently, the miR-181a-5p antagomir aggravated osteoporosis in old mice. Additionally, we predicted potential target genes via TargetScan and miRDB and identified bone morphogenetic protein 3 (BMP3) as the target gene. Moreover, the reduced expression of miR-181a-5p was validated in our hospitalized osteoporotic patients. These findings have substantial implications for the strategies targeting miR-181a-5p to prevent osteoporosis and potential related fractures.

Erdheim-Chester disease with asymmetric talus involvement: A case report.

BACKGROUND: Erdheim-Chester disease (ECD) is a rare multi-system or multi-organ histiocytic proliferative disease with diverse clinical manifestations, and the development of the disease is complex, which makes clinical diagnosis and treatment difficult. The characteristic clinical manifestations include multi-organ involvement, especially in the symmetrical diaphysis and metaphysis of the bilateral extremities. ECD with a unilateral talus lesion is extremely rare. Here, we report an unusual case of ECD invading the asymmetric talus and tibia without involving other organs. The patient had good outcome after surgery. CASE SUMMARY: We report a case of a 67-year-old man who was referred to our outpatient department because of left ankle chronic pain for 5 years, which exacerbated after a foot sprain 6 mo previously. We discovered multiple sclerotic lesions of the tibia and talus on his previous X-ray films, which were initially missed in a local hospital. Therefore, enhanced computer computed tomography (CT) and magnetic resonance imaging were performed. These examinations showed multiple lesions in the bone marrow cavity of the left tibia, and cortical sclerosis and osteonecrosis of the left talus. Specimens were collected via bone puncture from the two lesions, and a final diagnosis of ECD was confirmed by pathological and immunohistochemical examinations. In addition, other auxiliary examinations including head CT, pulmonary CT, spinal CT, abdominal CT, cardiac ultrasound and thyroid ultrasound showed no obvious abnormalities. The patient underwent surgery for the tibia lesion scraping and talus lesion scraping combined with cement casting. The patient started on a progressive rehabilitation at 4 wk, and felt no pain after surgery. During a 2-year follow-up period, the patient exercised normally without pain, and there were no signs of recurrence. CONCLUSION: This study shows that surgery treatment may also achieve good results for ECD patients with only bone involvement.

Arterial Calcification Is Regulated Via an miR-204/DNMT3a Regulatory Circuit Both In Vitro and in Female Mice.

Arterial calcification is a common cardiovascular disease that initiates from a process of osteoblastic differentiation of vascular smooth muscle cells (VSMCs). Accumulating evidence has demonstrated that microRNAs play an important role in regulating arterial calcification. miR-204 was significantly downregulated in calcified human renal arteries from patients with uremia; calcified arteries of mice, due to 5/6 nephrectomy with a high-phosphate diet (5/6 NTP); and in VSMCs induced by high phosphate concentration. The overexpression of miR-204 alleviated the osteoblastic differentiation of VSMCs. Bisulphite sequencing PCR revealed that CpG sites upstream of miR-204 DNA were hypermethylated in calcified VSMCs; in calcified arteries of mice, due to 5/6 NTP; and in calcified renal artery tissues from patients with uremia. Moreover, increased DNMT3a resulted in the hypermethylation of miR-204 in high phosphate concentration-induced VSMCs, whereas 5-aza-2'-deoxycytidine could restore the expression of miR-204 in high phosphate concentration-induced VSMCs. Moreover, we found that DNMT3a was the target of miR-204, and the methylation ratio of miR-204 was decreased significantly, meaning that the expression of miR-204 was restored when DNMT3a was knocked down by using DNMT3a small interfering RNA, resulting in abrogation of the effect of high phosphate concentration on VSMC calcification. The progress of arterial calcification is regulated by the miR-204/DNMT3a regulatory circuit.

Oestrogen Inhibits Arterial Calcification by Promoting Autophagy.

Arterial calcification is a major complication of cardiovascular disease. Oestrogen replacement therapy in postmenopausal women is associated with lower levels of coronary artery calcification, but its mechanism of action remains unclear. Here, we show that oestrogen inhibits the osteoblastic differentiation of vascular smooth muscle cells (VSMCs) in vitro and arterial calcification in vivo by promoting autophagy. Through electron microscopy, GFP-LC3 redistribution, and immunofluorescence analyses as well as measurement of the expression of the autophagosome marker light-chain I/II (LC3I/II) and autophagy protein 5 (Atg5), we show that autophagy is increased in VSMCs by oestrogen in vitro and in vivo. The inhibitory effect of oestrogen on arterial calcification was counteracted by 3-methyladenine (3MA) or knockdown of Atg5 and was increased by rapamycin. Furthermore, the inhibitory effect of oestrogen on arterial calcification and the degree of autophagy induced by oestrogen were blocked by a nonselective oestrogen receptor (ER) antagonist (ICI 182780), a selective oestrogen receptor alpha (ERα) antagonist (MPP), and ERα-specific siRNA. Our data indicate that oestrogen inhibits the osteoblastic differentiation of VSMCs by promoting autophagy through the ERα signalling pathway in vitro and arterial calcification in vivo by increasing autophagy. Our findings provide new insights into the mechanism by which oestrogen contributes to vascular calcification in vitro and in vivo.

SerpinE2 promotes multiple cell proliferation and drug resistance in osteosarcoma.

SerpinE2 is a member of the Serpins family, which could inhibit serine protease and promote tumor progression, particularly in tumor metastasis. However, at present, its role in the progression of osteosarcoma has not been determined. The present study analyzed the expression profiles of SerpinE2 in cancer tissues, including tissues from osteosarcoma of different stages. Higher expression of SerpinE2 was shown in osteosarcoma tissues, particularly in tissue from patients with metastasis and a tumor-node-metastasis stage II­III. Following chemotherapy, the SerpinE2 expression levels were shown to be higher than those at diagnosis. Cell proliferation and colony formation were increased after transfection with SerpinE2 over­expression vector. Additionally, drug resistance to bortezomib and doxorubicin treatment following SerpinE2 transfection was analyzed. MG­63 and SAOS­2 cells showed less sensitivity following transfection with SerpinE2. The cell cycle­related genes, cyclin­dependent kinase (CDK)4 and cyclin D1 were positively correlated with SerpinE2 expression in patient­derived tissue and in osteosarcoma cells. Finally, the high expression of SerpinE2 contributes to poor survival rates in patients with osteosarcoma. In conclusion, high expression of SerpinE2 in osteosarcoma stimulates cell proliferation, promotes drug­resistance, and results in poor survival by regulating CDK4 and cyclin D1. Thus, SerpinE2 could be a potential target for treatment of patients with osteosarcoma.

Co­culture of fibroblast­like synoviocytes with umbilical cord­mesenchymal stem cells inhibits expression of pro­inflammatory proteins, induces apoptosis and promotes chondrogenesis.

The present study aimed to investigate the effect of co­culture of fibroblast­like synoviocytes (FLS) with human umbilical cord­mesenchymal stem cells (UC­MSCs) on rheumatoid arthritis (RA) and to understand the mechanisms that mediate the induced changes. FLS and UC­MSCs were isolated and cultured individually, FLS were then cultured with or without UC­MSCs. The phenotype of UC­MSCs was analyzed prior to co­culture. The UC­MSCs were successfully isolated and expanded, and exhibited a fibroblast­like morphology. Enzyme­linked immunosorbent assay (ELISA) and reverse transcription­quantitative polymerase chain reaction (RT­qPCR) were performed to determine the expression levels of interleukin (IL)­1ß, IL­6, and chemokine (C­C motif) ligand (CCL)­2. The cell apoptosis rate was determined by flow cytometry. Furthermore, the RNAs of aggrecan and collagen type II were isolated and assessed in a chondrogenesis assay following co­culture for 7, 14, 21 and 28 days. Protein expression levels of apoptosis­related proteins, including B­cell lymphoma (Bcl­2), Bcl­2­associated X protein, p53 and phospho (p)­AKT, and growth differentiation factor­5 were analyzed by western blotting. ELISA and qRT­PCR demonstrated that compared with FLS cultured alone, co­culture with UC­MSCs significantly downregulates the expression levels of IL­1ß, IL­6 and CCL­2. Additionally, the percentage of apoptotic cells was significantly increased in the co­cultured cells (P<0.05), and the relative RNAs levels of aggrecan and collagen type II were increased compared with FLS alone. Furthermore, the expression levels of Bcl­2 (P<0.05) and p­AKT (P<0.05) were significantly decreased, whereas, p53 (P=0.001), Bax (P<0.01) and GDF­5 (P<0.01) were increased by co­culture of FLS with UC­MSCs compared with FLS alone. In conclusion, co­culture of FLS with UC­MSCs may be important and clinically useful for the treatment of RA by inhibiting the expression of pro­inflammatory mediators, inducing apoptosis and promoting chondrogenesis.