Pyroptosis in Osteoarthritis: Molecular Mechanisms and Therapeutic Implications.

Osteoarthritis (OA) is a chronic disease that causes pain and functional impairment by affecting joint tissue. Its global impact is noteworthy, causing significant economic losses and property damage. Despite extensive research, the underlying pathogenesis of OA remain an area of ongoing investigation. It has recently been discovered that the OA progression is significantly influenced by pyroptosis. Pyroptosis is a complex process that involves three pathways culminating in the assembly of Gasdermin-D (GSDMD)-N-terminal (GSDMD-NT) into pores through aggregation on the plasma membrane. The aggregation of GSDMD-NT proteins stimulates the release of inflammatory mediators, such as Interleukin-1ß (IL-1ß), Interleukin-18 (IL-18), and Matrix Metallopeptidase 13 (MMP13), ultimately leading to cellular lysis. The pyroptosis process in specific cells, including synovial macrophages, fibroblast-like synoviocytes (FLS), chondrocytes, and subchondral osteoblasts, contributs factor to the development of OA. Currently, the specific cells that undergo pyroptosis first are not yet fully understood, and it remains unknown whether pyroptosis in one cell can trigger the same process in other cells. Therefore, targeting pyroptosis could potentially offer a novel treatment approach for OA patients. We present a comprehensive analysis of the molecular mechanisms and key features of pyroptosis. We also outline the current research progress on various aspects, including synovial tissue, articular cartilage, extracellular matrix (ECM), and subchondral bone, with a focus on pyroptosis. The aim is to provide theoretical references for the effective management of OA.

Complete resorption of the humerus in metastatic thyroid carcinoma: a case report.

BACKGROUND: Thyroid carcinoma is the most common endocrinological malignancy, but its spread to bone is rare. Particularly, bone metastases leading to complete resorption of the humerus are extremely uncommon. We aimed to explore factors affecting treatment decision in humeral metastasis by presenting a case and analyze the possible treatments via conducting a literature review. CASE PRESENTATION: We described a case of a 68-year-old woman experiencing chronic pain in her right upper arm for six years. Clinical, radiological, and pathological evaluations confirmed humeral metastasis from thyroid carcinoma. Surgical treatments like tumor removal or limb amputation were suggested for prolonging life and pain relief, but the patient refused them and pursued conservative managements such as herbal medicine, radioactive iodine (131I) therapy, and Levothyroxine Sodium(L-T4). The humeral destruction aggravated gradually, ultimately leading to complete resorption of her right humerus. The patient could not move her right shoulder, but her forearm motion was almost normal; thus, she could complete most of her daily living activities independently. Surgical treatments such as limb amputation were advised but she still refused them for preservation of the residual limb function and preferred conservative managements. CONCLUSION: A personalized multidisciplinary approach is important for patients with bone metastasis. The balance between limb amputation for life-prolonging and pain relief and limb salvage for preservation of residual function and social and psychological well-being should be considered. Our literature review revealed that some novel surgical treatments and techniques are available for bone metastases. This case adds to our current understanding of bone metastases and will contribute to future research and treatments.

Proteomics and Metabolomics Analysis Reveal the Regulation Mechanism of Linoleate Isomerase Activity and Function in Propionibacterium acnes.

Conjugated linoleic acid (CLA) holds significant application prospects due to its anticancer, anti-atherosclerosis, lipid-lowering, weight-loss, and growth-promoting functions. The key to its efficient production lies in optimizing the biocatalytic performance of linoleic acid isomerase (LAI). Here, we constructed a Propionibacterium acnes mutant library and screened positive mutants with high linoleate isomerase activity. The proteomics and metabolomics were used to explore the mechanism in the regulation of linoleic acid isomerase activity. High-throughput proteomics revealed 104 differentially expressed proteins unique to positive mutant strains of linoleic acid isomerase of which 57 were upregulated and 47 were downregulated. These differentially expressed proteins were primarily involved in galactose metabolism, the phosphotransferase system, starch metabolism, and sucrose metabolism. Differential metabolic pathways were mainly enriched in amino acid biosynthesis, including glutamate metabolism, the Aminoacyl-tRNA biosynthesis pathway, and the ABC transporter pathway. The upregulated metabolites include dl-valine and Acetyl coA, while the downregulated metabolites include Glutamic acid and Phosphoenolpyruvate. Overall, the activity of linoleic acid isomerase in the mutant strain was increased by the regulation of key proteins involved in galactose metabolism, sucrose metabolism, and the phosphotransferase system. This study provides a theoretical basis for the development of high-yield CLA food.

Identification of long noncoding RNAs of silkworm at the early stage of Bombyx mori bidensovirus infection.

Bombyx mori bidensovirus (BmBDV) is one of the most important pathogens of silkworm. It mainly infects midgut cells of silkworm and causes losses to the sericulture industry. Long noncoding RNAs (lncRNAs) have been reported to play an important role in the regulation of antiviral immune response in silkworm. To explore whether lncRNAs are involved in BmBDV infection and immune response of silkworm, we performed a comparative transcriptome analysis to identify the lncRNAs and mRNAs between the BmBDV infected and noninfected silkworm larvae at the early stage. A total of 16,069 genes and 974 candidate lncRNAs were identified, among which 142 messenger RNA (mRNAs) and four lncRNAs were differentially expressed (DE). Target gene prediction revealed that 142 DEmRNAs were coexpressed with four DElncRNAs, suggesting that the expression of mRNA is mainly affected through trans-regulation activities. A regulatory network of DElncRNAs and DEmRNAs was constructed, showing that many genes targeted by different DElncRNAs are involved in metabolism and immunity, which implies that these genes and lncRNAs play an important role in the replication of BmBDV. Our results will help us to improve our understanding of lncRNA-mediated regulatory roles in BmBDV infection, providing a new perspective for further exploring the interaction between host and BmBDV.

Cartilage organoids and osteoarthritis research: a narrative review.

Osteoarthritis (OA) is one of the most common degenerative joint diseases, significantly impacting individuals and society. With the acceleration of global aging, the incidence of OA is increasing. The pathogenesis of osteoarthritis is not fully understood, and there is no effective way to alleviate the progression of osteoarthritis. Therefore, it is necessary to develop new disease models and seek new treatments for OA. Cartilage organoids are three-dimensional tissue masses that can simulate organ structure and physiological function and play an important role in disease modeling, drug screening, and regenerative medicine. This review will briefly analyze the research progress of OA, focusing on the construction and current development of cartilage organoids, and then describe the application of cartilage organoids in OA modeling, drug screening, and regeneration and repair of cartilage and bone defects. Finally, some challenges and prospects in the development of cartilaginous organoids are discussed.

Ivabradine protects rats against myocardial infarction through reinforcing autophagy via inhibiting PI3K/AKT/mTOR/p70S6K pathway.

Ivabradine (Iva), a heart rate reducing agent that specifically inhibits the pacemaker I(f) ionic current, has been demonstrated to be cardioprotective in many cardiovascular diseases. Autophagy is an evolutionarily conserved metabolic process that regulates cardiac homeostasis. This study is aimed to explore whether autophagy is functionally involved in the cardioprotective effect of Iva in a rat model of myocardial infarction (MI). We observed that Iva treatment (po, 10 mg/kg/day) showed significant recovery on the hemodynamics parameters in MI rats, including left ventricular systolic pressure, left ventricular end diastolic pressure, and maximal ascending/descending rate of left ventricular pressure. Also, Iva treatment dramatically decreased infarct size, inhibited myocardial apoptosis, and reduced the levels of pro-inflammatory cytokines tumor necrosis factor (TNF)-α, interleukin (IL)-1ß and IL-6 in MI rats. Moreover, Iva treatment enhanced autophagy and inhibited PI3K/AKT/mTOR/p70S6K pathway in MI rats. Simultaneously, we observed that autophagy enhancer rapamycin (ip, 10 mg/kg/day) showed similar cardioprotective effects with Iva. Furthermore, we observed that addition of autophagy inhibitor 3-methyladenine (ip, 10 mg/kg/day) counteracted the therapeutic effect of Iva, addressing that Iva attenuated post-MI cardiac injury by enhancing autophagy. In summary, these findings demonstrated that Iva attenuated MI in rats by enhancing autophagy, and PI3K/AKT/mTOR/p70S6K pathway might be involved in the process. Autophagy activation by Iva may be a potential therapeutic strategy for the treatment of MI.

Compound Discovery and Structure-Activity Relationship Study of Neoantimycins Against Drug-Resistant Cancer Cells.

Four neoantimycins H-K (1-4) with C1-keto, including the new ones (1-2), were isolated from the culture of Streptomyces conglobatus RJ8. After enzymatically converting into their respective reduced type derivatives (5-8) in vitro, the absolute structures of 1-8 were established/reconfirmed by analyzing hydrolyzed components. The obtained NATs (4, 7, and 8) exhibited excellent cytotoxicity against drug-resistant colon and gastric cancer cells but low toxicity in the noncancerous cell. Further SAR investigation suggested that C1-hydroxyl, C9-isobutyl, and N-formyl contribute to the antiproliferation remarkably.

Optimal antithrombotic therapy in patients with atrial fibrillation following percutaneous coronary intervention: A systemic review and meta-analysis.

A challenge for antithrombotic treatment is patients who present with atrial fibrillation (AF) and acute coronary syndrome, particularly in patients who have undergone coronary percutaneous intervention with stenting (PCIS). In the present study, a total of nine observational trials published prior to July 2017 that investigated the effects of dual antiplatelet therapy (DAPT; aspirin + clopidogrel) and triple oral antithrombotic therapy (TOAT; DAPT + warfarin) among patients with AF concurrent to PCIS were collected from the Medline, Cochrane and Embase databases and conference proceedings of cardiology, gastroenterology and neurology meetings. A meta-analysis was performed using fixed- or random-effect models according to heterogeneity. The subgroups were also analyzed on the occurrence of major adverse cardiac events (MACE), stroke and bleeding events in the two treatment groups. Analysis of baseline characteristics indicated that there was no significant difference in the history of coexistent disease or conventional therapies between the DAPT and TOAT groups. The primary end point incidence was 2,588 patients in the DAPT group (n=13,773) and 871 patients in the TOAT group (n=5,262) following pooling of all nine trials. There was no statistically significant difference in the incidence of primary end points between the DAPT and TOAT groups. Odds ratio (OR)=0.96, 95% confidence interval (CI)=0.73-1.27, P=0.79, with heterogeneity between trials (I2=82%, P<0.00001). Subsequently, on subgroup analysis, the results indicated no increased risk of major bleeding or ischemic stroke in the DAPT or TOAT group. However, compared with the TOAT group, there was an apparent increased risk of MACE plus ischemic stroke in the DAPT group (OR=1.62, 95% CI=1.43-1.83, P<0.00001) with heterogeneity between trials (I2=70%, P=0.01). In conclusion, the present meta-analysis suggests that TOAT (aspirin + clopidogrel + warfarin) therapy for patients with AF concurrent to PCIS significantly reduced the risk of MACE and stroke compared with DAPT (aspirin + clopidogrel) therapy. Further randomized controlled clinical trials are required to confirm the efficacy of the optimal antithrombotic therapy in patients with AF following PCIS.

[Expression and Significance of CD4+ CD25+ CDl27low Regulatory T Cells, TGF-ß and Notch1 mRNA in Patients with Idiopathic Thrombocytopenic Purpura].

OBJECTIVE: To detect the expression levels of CD4(+) CD25(+) CDl27(low) Treg cells, TGF-ß and Notch1 mRNA in peripheral blood of the patients with idiopathic thrombocytopenic purpura (IPT) before and after treatment, and to investigate their significance in the pathogenesis of ITP. METHODS: Peripheral blood was collected from 30 newly diagnosed patients with ITP and 20 normal controls, then the number of CD4(+) CD25(+) Treg and CD4(+) CD25(+) CDl27(low) Treg were detected by the flow cytometry. Plasma TGF-ß level was determined by ELISA. Total RNA was extracted and the expression level of Notch1 mRNA was measured by real-time Q-PCR. RESULTS: The expression levels of CD4(+) CD25(+) CDl27(low) Treg and CD4(+) CD25(+) Treg in newly diagnosed ITP group were significantly lower than those in normal controls. After treatment, the proportion of Tregs increased to (5.17% ± 0.74%) and (4.16% ± 0.68%), and was higher than that in newly diagnosed patients. The TGF-ß level in peripheral blood of newly-diagnosed patients was obviously lower than that in normal controls, and was (961.53 ± 60.10) ng/L after treatment and was significantly higher than that in newly diagnosed patients; the expression level of Notch1 mRNA in peripheral blood of patients in newly-diagnosed group was obviously lower than that in control, and was (1.35 ± 0.10) after treatment that was higher than that in newly-diagnosed group. After treatment, the proportion of Treg cells, level of TGF-ß and erpression level of Notch1 mRNA in effective group were higher than those in effective group, improved group and ineffective group, and there was significant difference (P <0.01). The expression level of TGF-ß and Notch1 mRNA in ITP patients possitively correlated to CD4(+) CD25(+) CDl27(low) (P <0.01). CONCLUSIONS: The levels of CD4(+) CD25(+) CDl27(low) Treg, TGF-ßand Notch1 mRNA in peripheral blood of the patients with ITP are significantly lower than those of normal control, suggesting that there is significant abnormal immunoregulation in ITP patients. In the ITP patients the levels of CD4(+) CD25(+) CDl27(low) Treg postively correlated with Notch1 mRNA expression, indicating that Notch signal may be revalent to Treg's immunosuppression function.

Resveratrol prevents doxorubicin-induced cardiotoxicity in H9c2 cells through the inhibition of endoplasmic reticulum stress and the activation of the Sirt1 pathway.

Treatment with doxorubicin (DOX) is one of the major causes of chemotherapy-induced cardiotoxicity and is therefore, the principal limiting factor in the effectiveness of chemotherapy for cancer patients. DOX­induced heart failure is thought to result from endoplasmic reticulum (ER) stress and cardiomyocyte apoptosis. Resveratrol (RV), a polyphenol antioxidant found in red wine, has been shown to play a cardioprotective role. The aim of the present study was to examine the effects of RV on DOX­induced cardiotoxicity in H9c2 cells. We hypothesized that RV would protect H9c2 cells against DOX­induced ER stress and subsequent cell death through the activation of the Sirt1 pathway. Our results demonstrated that the decrease observed in the viability of the H9c2 cells following exposure to DOX was accompanied by a significant increase in the expression of the ER stress­related proteins, glucose­regulated protein 78 (GRP78) and C/EBP homologous protein (CHOP). However, we found that RV downregulated the expression of ER stress marker protein in the presence of DOX and restored the viability of the H9c2 cells. Exposure to RV or DOX alone only slightly increased the protein expression of Sirt1, whereas a significant increase in Sirt1 protein levels was observed in the cells treated with both RV and DOX. The Sirt1 inhibitor, nicotinamide (NIC), partially neutralized the effects of RV on the expression of Sirt1 in the DOX­treated cells and completely abolished the effects of RV on the expression of GRP78 and CHOP. The findings of our study suggest that RV protects H9c2 cells against DOX­induced ER stress through ER stabilization, and more specifically through the activation of the Sirt1 pathway, thereby leading to cardiac cell survival.

Testosterone replacement therapy promotes angiogenesis after acute myocardial infarction by enhancing expression of cytokines HIF-1a, SDF-1a and VEGF.

In order to investigate the effects of testosterone-replacement therapy on peripheral blood stem cells and angiogenesis after acute myocardial infarction, a castrated rat acute myocardial infarction model was established by ligation of the left anterior descending coronary followed by treatment with testosterone. CD34(+) cells in myocardium and in peripheral blood after 1 and 3 days were measured by immunohistochemistry and flow cytometry, respectively. In the early phase of acute myocardial infarction, the expression levels of hypoxia-inducible factor 1a (HIF-1a), stromal cell-derived factor 1a (SDF-1a) and vascular endothelium growth factor (VEGF) in ischemic myocardium were determined by real time RT-PCR and immunohistochemistry, respectively. Infarct size, cardiomyocyte apoptosis, capillary density and cardiac function were assessed after 28 days. These results showed that the number of CD34(+) cells in the peripheral blood and in myocardium was significantly decreased in castrated rats, and the early expression levels of HIF-1a, SDF-1a and VEGF in the myocardium were also decreased. Furthermore, reduced capillary density, worsened cardiac function, increased infarct size and cardiomyocyte apoptosis at 28 days post-infarction were found in castrated rats. But these adverse effects could be reversed by testosterone-replacement therapy. These findings suggested that testosterone can increase the mobilization and homing of CD34(+) cells into the ischemic myocardium and further promote neoangiogenesis after myocardial infarction. The pro-angiogenesis effect of testosterone-replacement therapy is associated with the enhanced expression of HIF-1a, SDF-1a and VEGF in myocardium after myocardial infarction.