RESUMO
OBJECTIVES: Wnt pathway upregulation contributes to knee osteoarthritis (OA) through osteoblast differentiation, increased catabolic enzymes, and inflammation. The small-molecule Wnt pathway inhibitor, lorecivivint (SM04690), which previously demonstrated chondrogenesis and cartilage protection in an animal OA model, was evaluated to elucidate its mechanism of action. DESIGN: Biochemical assays measured kinase activity. Western blots measured protein phosphorylation in human mesenchymal stem cells (hMSCs), chondrocytes, and synovial fibroblasts. siRNA knockdown effects in hMSCs and BEAS-2B cells on Wnt pathway, chondrogenic genes, and LPS-induced inflammatory cytokines was measured by qPCR. In vivo anti-inflammation, pain, and function were evaluated following single intra-articular (IA) lorecivivint or vehicle injection in the monosodium iodoacetate (MIA)-induced rat OA model. RESULTS: Lorecivivint inhibited intranuclear kinases CDC-like kinase 2 (CLK2) and dual-specificity tyrosine phosphorylation-regulated kinase 1A (DYRK1A). Lorecivivint inhibited CLK2-mediated phosphorylation of serine/arginine-rich (SR) splicing factors and DYRK1A-mediated phosphorylation of SIRT1 and FOXO1. siRNA knockdowns identified a role for CLK2 and DYRK1A in Wnt pathway modulation without affecting ß-catenin with CLK2 inhibition inducing early chondrogenesis and DYRK1A inhibition enhancing mature chondrocyte function. NF-κB and STAT3 inhibition by lorecivivint reduced inflammation. DYRK1A knockdown was sufficient for anti-inflammatory effects, while combined DYRK1A/CLK2 knockdown enhanced this effect. In the MIA model, lorecivivint inhibited production of inflammatory cytokines and cartilage degradative enzymes, resulting in increased joint cartilage, decreased pain, and improved weight-bearing function. CONCLUSIONS: Lorecivivint inhibition of CLK2 and DYRK1A suggested a novel mechanism for Wnt pathway inhibition, enhancing chondrogenesis, chondrocyte function, and anti-inflammation. Lorecivivint shows potential to modify structure and improve symptoms of knee OA.
Assuntos
Anti-Inflamatórios/uso terapêutico , Imidazóis/uso terapêutico , Indazóis/uso terapêutico , Osteoartrite do Joelho/tratamento farmacológico , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Tirosina Quinases/antagonistas & inibidores , Piridinas/uso terapêutico , Via de Sinalização Wnt/efeitos dos fármacos , Animais , Western Blotting , Células Cultivadas , Modelos Animais de Doenças , Humanos , Reação em Cadeia da Polimerase , Ratos , Quinases DyrkRESUMO
The incidence, risk factors, and morbidity were retrospectively reviewed of 110 intestinal injuries that occurred during gynecologic operations from January 1984 through December 2003 performed for benign and malignant conditions. The incidence of bowel injury was 0.54% in this series. Of the 110 bowel injuries, 37.3% occurred during opening of the peritoneal cavity, 38.2% during adhenolysis and pelvic dissection, 9% during laparoscopy, 9.1% sustained at vaginal operations, and 8.2% during dilatation and curettage. The small intestine was injured in 75.5% and large bowel in 24.5% of cases; 76.4% of all the injuries were minor, and 23.6% major. Standard surgical repair procedure of the bowel injury produced satisfactory results. It is recommended that gynecologists acquire a basic knowledge in the prevention and principles of management of intestinal injuries. Adherence to the standard surgical techniques during gynecologic operations and anticipation of bowel injury in high-risk patients will contribute to minimize the occurrence of such injuries.
Assuntos
Procedimentos Cirúrgicos em Ginecologia , Intestinos/lesões , Complicações Intraoperatórias/epidemiologia , Adulto , Idoso , Feminino , Humanos , Incidência , Complicações Intraoperatórias/cirurgia , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de RiscoRESUMO
Bone defects in revision knee arthroplasty are often located in load-bearing regions. The goal of this study was to determine whether a physiologic load could be used as an in situ osteogenic signal to the scaffolds filling the bone defects. In order to answer this question, we proposed a novel translation procedure having four steps: (1) determining the mechanical stimulus using finite element method, (2) designing an animal study to measure bone formation spatially and temporally using micro-CT imaging in the scaffold subjected to the estimated mechanical stimulus, (3) identifying bone formation parameters for the loaded and non-loaded cases appearing in a recently developed mathematical model for bone formation in the scaffold and (4) estimating the stiffness and the bone formation in the bone-scaffold construct. With this procedure, we estimated that after 3 years mechanical stimulation increases the bone volume fraction and the stiffness of scaffold by 1.5- and 2.7-fold, respectively, compared to a non-loaded situation.