Toddalolactone Protects Against Osteoarthritis by Ameliorating Chondrocyte Inflammation and Suppressing Osteoclastogenesis

Background: Osteoarthritis (OA) is widely recognized as the most common chronic joint disease accompanied by progressive cartilage and subchondral bone damage. Toddalolactone (TOD), a natural compound extracted from Toddalia asiatica (L.) Lam., has been widely used in the treatment of stroke, rheumatoid arthritis, and oedema. Nevertheless, what TOD acts as in the pathogenesis and progression of OA hasn’t been reported. In this investigation, we have aimed to determine how TOD affects OA in vitro and in vivo.Methods: LPS (10μg/ml) was employed to induce chondrocyte inflammation or RANKL to induce osteoclast differentiation in bone marrow derived macrophages (BMMs); Meanwhile, the effects of TOD on chondrocyte inflammation and osteoclast differentiation were evaluated. Anterior cruciate ligament transection (ACLT) was performed to develop an OA animal model and study the effects of TOD.Results: We found that TOD inhibited the expression of inflammatory and catabolic mediators ( IL-6, IL-8, TNF-α, MMP2, MMP9, and MMP13) in LPS-treated chondrocytes in vitro. Furthermore, TOD was proven to inhibit RANKL-induced-osteoclastogenesis and inhibit the expression of marker genes (NFATc1 and c-fos). Our data also confirmed that TOD suppressed the destruction of articular cartilage and osteoclastogenesis by inhibiting the activation of the NF-κB and MAPK signalling pathways. In the ACLT mouse model, we found that TOD attenuated the ACLT-induced cartilage erosion and inhibited bone resorption.Conclusions: These results showed that TOD can be adopted as a potential therapeutic agent for OA.

Inhibition of SYK and cSrc kinases can protect bone and cartilage in preclinical models of osteoarthritis and rheumatoid arthritis

The pathophysiology of osteoarthritis (OA) includes the destruction of subchondral bone tissue and inflammation of the synovium. Thus, an effective disease-modifying treatment should act on both of these pathogenetic components. It is known that cSrc kinase is involved in bone and cartilage remodeling, and SYK kinase is associated with the inflammatory component. Thus the aim of this study was to characterize the mechanism of action and efficacy of a small molecule multikinase inhibitor MT-SYK-03 targeting SYK and cSrc kinases among others in different in vitro and in vivo arthritis models. The selectivity of MT-SYK-03 kinase inhibition was assayed on a panel of 341 kinases. The compound was evaluated in a set of in vitro models of OA and in vivo OA and RA models: surgically-induced arthritis (SIA), monosodium iodoacetate-induced arthritis (MIA), collagen-induced arthritis (CIA), adjuvant-induced arthritis (AIA). MT-SYK-03 inhibited cSrc and SYK with IC50 of 14.2 and 23 nM respectively. Only five kinases were inhibited > 90% at 500 nM of MT-SYK-03. In in vitro OA models MT-SYK-03 reduced hypertrophic changes of chondrocytes, bone resorption, and inhibited SYK-mediated inflammatory signaling. MT-SYK-03 showed preferential distribution to joint and bone tissue (in rats) and revealed disease-modifying activity in vivo by halving the depth of cartilage erosion in rat SIA model, and increasing the pain threshold in rat MIA model. Chondroprotective and antiresorptive effects were shown in a monotherapy regime and in combination with methotrexate (MTX) in murine and rat CIA models; an immune-mediated inflammation in rat AIA model was decreased. The obtained preclinical data support inhibition of cSrc and SYK as a viable strategy for disease-modifying treatment of OA. A Phase 2 clinical study of MT-SYK-03 is to be started.

Apelin Promotes Endothelial Progenitor Cell Angiogenesis in Rheumatoid Arthritis Disease via the miR-525-5p/Angiopoietin-1 Pathway

Angiogenesis is a critical process in the formation of new capillaries and a key participant in rheumatoid arthritis (RA) pathogenesis. The adipokine apelin (APLN) plays critical roles in several cellular functions, including angiogenesis. We report that APLN treatment of RA synovial fibroblasts (RASFs) increased angiopoietin-1 (Ang1) expression. Ang1 antibody abolished endothelial progenitor cell (EPC) tube formation and migration in conditioned medium from APLN-treated RASFs. We also found significantly higher levels of APLN and Ang1 expression in synovial fluid from RA patients compared with those with osteoarthritis. APLN facilitated Ang1-dependent EPC angiogenesis by inhibiting miR-525-5p synthesis via phospholipase C gamma (PLCγ) and protein kinase C alpha (PKCα) signaling. Importantly, infection with APLN shRNA mitigated EPC angiogenesis, articular swelling, and cartilage erosion in ankle joints of mice with collagen-induced arthritis. APLN is therefore a novel therapeutic target for RA.

Myrtenal and β-caryophyllene oxide screened from Liquidambaris Fructus suppress NLRP3 inflammasome components in rheumatoid arthritis

Background Liquidambaris Fructus (LF) is the infructescence of Liquidambar formosana. In Traditional Chinese Medicine, LF has been used to treat joint pain, a common symptom of arthritis and rheumatism; however, a lack of pharmacological evidence has limited its applications in modern clinics. Therefore, this study aims to explore the protective effect of LF on rheumatoid arthritis (RA) and to identify its active ingredients. Methods Rats with adjuvant-induced arthritis (AIA) were divided into 4 groups and administered petroleum ether extract of LF (PEL), ethyl acetate extract of LF (EEL), water extract of LF (WEL), or piroxicam (PIR) respectively for 3 weeks. Two additional groups were used as normal control (NC) and model control (MC) and administered distilled water as a placebo. The clinical scores for arthritis, bone surface, synovial inflammation and cartilage erosion were used to evaluate the therapeutic efficacy of each treatment. The serum IL-1β and TNF-α level and the expression of NLRP3, IL-1β and caspase-1 p20 in the synovial tissue of AIA rats were evaluated by ELISA and Western blot. The active ingredients of LF were investigated using network pharmacology and molecular docking methods, and their inhibition of NLRP3 inflammasome activation was verified in the human rheumatoid arthritis fibroblast-like synovial cells (RA-FLS) model. Results PEL could alleviate paw swelling, bone and joint destruction, synovial inflammation and cartilage erosion in the AIA rats, with significantly superior efficacy to that of EEL and WEL. PEL reduced IL-1β and TNF-α serum levels, and attenuated the upregulation of NLRP3, IL-1β and caspase-1 p20 expression in the synovial tissue of AIA rats. Network pharmacology and molecular docking results indicated that myrtenal and β-caryophyllene oxide were the main two active ingredients of PEL, and these two compounds showed significant inhibition on TNF-α, NLRP3, IL-1β and caspase-1 p20 expression in RA-FLS. Conclusions Myrtenal and β-caryophyllene oxide screened from PEL could suppress the activation of NLRP3 inflammasome, thereby alleviating RA symptoms.

CXCL13/CXCR5 axis facilitates endothelial progenitor cell homing and angiogenesis during rheumatoid arthritis progression

Angiogenesis is a critical process in the formation of new capillaries and a key participant in rheumatoid arthritis (RA) pathogenesis. The chemokine (C-X-C motif) ligand 13 (CXCL13) plays important roles in several cellular functions such as infiltration, migration, and motility. We report significantly higher levels of CXCL13 expression in collagen-induced arthritis (CIA) mice compared with controls and also in synovial fluid from RA patients compared with human osteoarthritis (OA) samples. RA synovial fluid increased endothelial progenitor cell (EPC) homing and angiogenesis, which was blocked by the CXCL13 antibody. By interacting with the CXCR5 receptor, CXCL13 facilitated vascular endothelial growth factor (VEGF) expression and angiogenesis in EPC through the PLC, MEK, and AP-1 signaling pathways. Importantly, infection with CXCL13 short hairpin RNA (shRNA) mitigated EPC homing and angiogenesis, articular swelling, and cartilage erosion in ankle joints of mice with CIA. CXCL13 is therefore a novel therapeutic target for RA.

S1P Increases VEGF Production in Osteoblasts and Facilitates Endothelial Progenitor Cell Angiogenesis by Inhibiting miR-16-5p Expression via the c-Src/FAK Signaling Pathway in Rheumatoid Arthritis

Angiogenesis is a critical process in the formation of new capillaries and a key participant in rheumatoid arthritis (RA) pathogenesis. Vascular endothelial growth factor (VEGF) stimulation of endothelial progenitor cells (EPCs) facilitates angiogenesis and the progression of RA. Phosphorylation of sphingosine kinase 1 (SphK1) produces sphingosine-1-phosphate (S1P), which increases inflammatory cytokine production, although the role of S1P in RA angiogenesis is unclear. In this study, we evaluated the impact of S1P treatment on VEGF-dependent angiogenesis in osteoblast-like cells (MG-63 cells) and the significance of SphK1 short hairpin RNA (shRNA) on S1P production in an in vivo model. We found significantly higher levels of S1P and VEGF expression in synovial fluid from RA patients compared with those with osteoarthritis by ELISA analysis. Treating MG-63 cells with S1P increased VEGF production, while focal adhesion kinase (FAK) and Src siRNAs and inhibitors decreased VEGF production in S1P-treated MG-63 cells. Conditioned medium from S1P-treated osteoblasts significantly increased EPC tube formation and migration by inhibiting miR-16-5p synthesis via proto-oncogene tyrosine-protein kinase src (c-Src) and FAK signaling in chick chorioallantoic membrane (CAM) and Matrigel plug assays. Infection with SphK1 shRNA reduced angiogenesis, articular swelling and cartilage erosion in the ankle joints of mice with collagen-induced arthritis (CIA). S1P appears to have therapeutic potential in RA treatment.

Comprehensive Review on Ayurvedic Formulations and Herbal Medicines for Treatment of Rheumatoid Arthritis

Rheumatoid arthritis, an autoimmune inflammatory disorder is characterized by progressive cartilage erosion leading to joint destruction, pain, stiffness, and swelling. Although the etiology of the disease is unknown, genetic changes due to factors such as environmental agents, immune response towards infectious agents influence rheumatoid arthritis. Earlier NSAIDs were the first choice of drugs for the treatment of disease but due to having certain side effects and limitations, herbal therapies which possess higher efficacy and safety are now in demand. There are hundreds of plants that have phytoconstituents that exhibit anti-inflammatory activity. A combination of plants is used to make polyherbal formulations that act synergistically to give anti-arthritic activity. The review is about the botanicals and traditional formulations which have been clinically tested for the treatment of Rheumatoid arthritis.

CS-semi5 Inhibits NF-κB Activation to Block Synovial Inflammation, Cartilage Loss and Bone Erosion Associated With Collagen-Induced Arthritis

Rheumatoid arthritis (RA) is a chronic, systemic autoimmune disease that affects 1% of the population. CS-semi5 is a semisynthetic chondroitin sulfate. In this study, CS-semi5 was shown to have positive effects on a model of collagen-induced arthritis (CIA). CS-semi5 treatment had obvious effects on weight loss and paw swelling in CIA mice. Post-treatment analysis revealed that CS-semi5 alleviated three main pathologies (i.e., synovial inflammation, cartilage erosion and bone loss) in a dose-dependent manner. Further study showed that CS-semi5 could effectively reduce TNF‐α and IL‐1β production in activated macrophages via the NF‐κB pathway. CS-semi5 also blocked RANKL-trigged osteoclast differentiation from macrophages. Therefore, CS-semi5 may effectively ameliorate synovial inflammation, cartilage erosion and bone loss in RA through NF-κB deactivation.

Histone Demethylase UTX Compromises Articular Chondrocyte Anabolism and Aggravates Osteoarthritic Degeneration

Histone demethylase UTX removes repressive trimethyl groups at lysine 27 of histone 3 (H3K27me3) to regulate tissue integrity, while its role was not yet studied in articulating joint tissues in situ. We now found that UTX expression in articular chondrocytes positively correlated with human osteoarthritis. Utx overexpression induced chondrocyte dysfunction, cartilage degeneration and osteophyte induction in mice. In contrast, chondrocyte-specific Utx knockout in mice promoted gross articular morphology and delayed age- and collagenase-induced cartilage erosion, synovitis and osteophyte formation and largely eliminated disease-associated joint pain. Additionally, pharmacological inhibition of Utx through GSK-J4 preserved cartilage integrity. Our study is the first to suggest that Utx loss-mediated cartilage protection involved a dysregulation of polycomb repressive complex 2 core components EZH2, EED, and SUZ12 to induce H3K27 hypomethylation and a net anabolic effect. Specifically, Utx loss-of-function appears to involve, among others, Wnt10a signaling to reduce chondrocytic activities and an IGF-2-mediated stimulation of extracellular matrix synthesis.

Surgical Outcome and Quality of Life After Total Laryngectomy in Advanced Laryngeal Cancer- A Study in Combined Military Hospital, Dhaka

Introduction: Total laryngectomy is the gold standard treatment for advanced laryngeal cancer. Sacrifice of voice is one of the most important shortcomings of the procedure. Possibility of achieving good quality voice is greater with prosthesis compared to other method. Post laryngectomy voice rehabilitation with prosthesis yield excellent outcome in most of the cases. Swallowing, pulmonary and olfactory rehabilitation should be managed by multidisciplinary team for better quality of life (QoL). Objectives: The purpose of this study was to observe the outcomes of voice, swallowing pulmonary and olfactory rehabilitation and QoL following total laryngectomy. Methods: This cross sectional retrospective clinical study was conducted at the Head & Neck Oncology Unit, Combined Military Hospital (CMH), Dhaka. Total 57 candidates were selected. Diagnosis was done by thorough clinical examination, Fibre Optic Laryngoscopy. Contrast Enhanced Computed Tomography (CECT) scan of neck was done except few cases where MRI of neck was done for subtle cartilage erosion was suspected. Examination under anaesthesia, direct larangoscopy and biopsy was done for every cases. Candidates were post chemo-radiated/ radiated biopsy proven recurrent cases, clinically nonfunctional larynx with aspiration and radiologically evident of cartilage erosion. In all cases artificial voice prosthesis was used. All the laryngectomees underwent voice, swallowing, pulmonary and olfactory rehabilitation in laryngectomy club of head & neck oncology unit, CMH Dhaka for a period of 3 months as per standard protocol. Results: Among the 57 patients 42 of them are using voice prosthesis without any complications till to date. Voice rehabilitation started after wound healing & developed meaningful voice in around 6 weeks. Satisfactory speech & voice outcomes were observed near about 3 months. Voice quality was assessed by multivariate statistical analysis. Excellent voice was observed for 38 patients, good voice for 12 patients, fair voice for 05 patients and poor voice for 02 patients. Troubleshooting like mycotic infection developed in 6 patients which was managed by anti-fungal medication with regular appropriate cleaning, Pharyngocutaneous fistula developed in 5 patients, 3 healed later by pressure dressing and anticholinergic & 1 required exploration and flap reconstruction, 01 developed recurrent stomal stenosis which managed surgically by Y-V advancement. Prosthesis expelled out in 3 cases. 02 cases developed dysphagia due to tonicity of pharyngoesophageal (PE) segment & managed by botox injection. Significantly better voice & swallowing were reported by patients undergone laryngectomy alone in comparison with patients receiving adjuvant radiotherapy & patient undergoing salvage laryngectomy. Conclusion: Awareness should be developed as sacrifice of voice box is no more a permanent comorbidity of total laryngectomy. Excellent voice can be developed by insertion of voice prosthesis as well as swallowing pulmonary and olfactory rehabilitation following laryngectomy for better of QoL. Bangladesh J Otorhinolaryngol; April 2021; 27(1): 5-11