Stress management by benzodiazepines in septic shock and critical illness: mechanistic and clinical evidence supporting alternative sedative strategies.

Osteoarthritis (OA) is the most common degenerative joint disorder that is a major cause of disability in elderly individuals worldwide. Clinically, it is diagnosed based on a combination of characteristic symptoms, such as chronic joint pain, stiffness, swelling, and reduced range of motion, along with radiographic features, including joint space narrowing, osteophyte formation, and subchondral bone sclerosis []. Histopathologically, OA is characterized by the progressive destruction of the articular cartilage, synovial inflammation, and remodeling of the periarticular bone, ultimately leading to impaired joint function and diminished quality of life []. A central event in this degenerative process is the disruption of extracellular matrix (ECM) homeostasis: anabolic synthesis of key cartilage components such as aggrecan and type II collagen is suppressed, whereas catabolic degradation mediated by matrix metalloproteinases (MMPs) and aggrecanases is accelerated []. This imbalance between ECM synthesis and degradation directly contributes to cartilage erosion and loss of structural integrity []. The growing prevalence of OA, driven by aging demographics, obesity, and mechanical overuse, imposes substantial healthcare and socioeconomic burdens []. Despite its significant impact, existing therapies are largely palliative, with disease-modifying effectively attenuating the structural progression of OA still lacking. Inflammation, a conserved host defense mechanism, has been extensively studied under both infectious and sterile conditions []. Activation of pattern recognition receptors, such as Toll-like receptors (TLRs) initiates downstream signaling cascades that converge on transcription factors including nuclear factor κB (NF-κB) and activator protein-1, thereby inducing the expression of cytokines, chemokines, and effector enzymes []. For example, NF-κB activation drives the transcription of interleukin (IL)-1β, tumor necrosis factor (TNF)-α, IL-6, cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), and MMPs, which collectively shape the inflammatory microenvironment []. Mitogen-activated protein kinase (MAPK) signaling pathways, including p38 and c-Jun N-terminal kinase (JNK) pathways, similarly enhance inflammatory gene expression and regulate immune cell recruitment []. Although acute inflammation eliminates pathogens and initiates repair, failure of such resolution programs leads to chronic low-grade inflammation, contributing to metabolic disorders, atherosclerosis, and degenerative diseases []. Accumulating evidence highlights the critical role of inflammation in OA pathogenesis []. Xu . [] demonstrated that IL-1β and TNF-α suppress anabolic processes in chondrocytes while upregulating catabolic mediator levels, thereby tipping the balance toward cartilage breakdown. MMP-13 and a disintegrin and metalloproteinase with thrombospondin motifs-5 (ADAMTS-5) are the key enzymes mediating type II collagen and aggrecan degradation, respectively, in human OA cartilage and experimental models []. Synovitis, previously considered a secondary feature of OA, is now recognized as an early driving factor of disease progression, with the synovial tissue producing cytokines and proteases that perpetuate cartilage damage []. Moreover, cartilage degradation products act as damage-associated molecular patterns, activating TLR-mediated NF-κB signaling in chondrocytes and synoviocytes and establishing a self-perpetuating cycle of inflammation and ECM destruction []. Unlike autoimmune-driven inflammatory arthritis, OA inflammation remains compartmentalized within joints; however, its presence is strongly correlated with pain severity and radiographic progression [].