Preventive Effect of the Japanese Traditional Herbal Medicine Boiogito on Posttraumatic Osteoarthritis in Rats

Suppressive Activity of Boiogito, a Japanese Traditional Kampo Medicine, on Periostin Secretion in Human Fibroblast-Like Synoviocytes In Vitro

Background Knee osteoarthritis (KOA) is a prevalent degenerative disease that affects the knee joints, particularly among individuals aged over 40 years. It leads to pain, stiffness, and reduced quality of life; affects approximately 300 million individuals worldwide; and is increasing, particularly in developed nations. Although treatments for KOA range from conservative measures to surgical interventions, such as total knee arthroplasty (TKA), the financial burden of TKA in many countries underscores the urgent need for effective conservative therapies. The pathophysiology of KOA involves articular cartilage degeneration, increased subchondral bone turnover, synovitis, and periarticular soft tissue contracture. Abnormal bone turnover, intensified by factors, such as weight gain and knee injury, precedes cartilage degeneration. Synovitis, characterized by inflammation in the synovial tissue, plays a crucial role in perpetuating the disease by triggering a cascade of catabolic and proinflammatory mediators, including cytokines, such as interleukin (IL)-1 beta, tumor necrosis factor-alpha, and IL-13. Periostin, an extracellular matrix protein, is implicated in KOA progression, with its levels increasing with disease severity. Materials & methods In this study, the preventive effect of boiogito (BOT), a traditional herbal medicine, on periostin secretion in human fibroblast-like synoviocytes (hFLS) stimulated by IL-13 was investigated. Synoviocyte Growth Medium and recombinant human IL-13 were used for cell culture and stimulation. BOT was dissolved in phosphate-buffered saline and applied to cell cultures. Periostin secretion and mRNA expression were measured using enzyme-linked immunosorbent assay and quantitative reverse transcription polymerase chain reaction, respectively. Cell viability was assessed using an MTT assay, and signal transducer and activator of transcription factor 6 (STAT6) phosphorylation was examined using Western blotting. Results IL-13 stimulation of hFLS significantly increased periostin secretion, with levels rising above 20 ng/mL after 72 h of stimulation. Pretreatment with BOT dose-dependently suppressed periostin secretion, with doses of 1,000 μg/mL significantly reducing periostin levels. Furthermore, BOT inhibited periostin mRNA expression and STAT6 phosphorylation in IL-13-stimulated hFLS, suggesting its potential in modulating IL-13-mediated inflammatory pathways in KOA. Conclusion This study demonstrated the preventive effect of BOT on periostin secretion in IL-13-stimulated hFLS, highlighting its potential as a therapeutic agent for KOA. By inhibiting periostin production and downstream signaling pathways, BOT may offer a promising conservative treatment option for KOA, addressing the inflammatory cascade implicated in disease progression. Further research is warranted to elucidate the specific herbal components responsible for the therapeutic effects of BOT and to validate its efficacy in clinical settings.

The Preventive Effects of Platelet-Rich Plasma Against Knee Osteoarthritis Progression in Rats

BACKGROUND

In recent years, the intra-articular administration of platelet-rich plasma (PRP), a novel therapeutic strategy for knee osteoarthritis (KOA), has gained attention. However, the efficacy of PRP in inhibiting degenerative joint changes remains unclear. The current study aimed to evaluate the therapeutic effect of the intra-articular administration of PRP in rats with induced KOA.

MATERIALS AND METHODS

PRP was prepared from the whole blood of nine-week-old male Wistar rats via centrifugation at 25°C, 200 × g, for seven minutes. KOA was induced in the right knees of the rats via destabilization of the medial meniscus (DMM) surgery. The animals were divided into the control, sham, DMM, and DMM + PRP groups (n = 5 each). The rats in the DMM + PRP group received 50 μL of intra-articular PRP in the right knee joint four weeks after surgery. The rotarod test was conducted to assess locomotive function. Eight weeks after DMM surgery, the degree of medial meniscus extrusion was measured via computed tomography (CT) images on the right knee. Then, a histological analysis of the harvested knees was conducted. KOA progression was assessed using the Osteoarthritis Research Society International (OARSI) score. The number of multinucleated tartrate-resistant acid phosphatase (TRAP)-positive osteoclasts in the subchondral bone was counted via histological analysis.

RESULTS

The degree of medial meniscus extrusion did not significantly differ between the DMM and DMM + PRP groups. Similarly, there were no significant differences in the walking time based on the rotarod test between the DMM and DMM + PRP groups. However, the DMM group had a significantly higher OARSI score than the DMM + PRP group. The number of TRAP-positive osteoclasts in the subchondral bone of the DMM group increased over time, peaking four weeks after surgery. The DMM + PRP group had a higher number of TRAP-positive osteoclasts in the subchondral bone than the control group. However, there was no significant difference between the number of TRAP-positive osteoclasts between the DMM group and the control and sham groups.

CONCLUSION

The intra-articular administration of PRP may inhibit KOA progression in a rat model, especially in the articular cartilage degradation and osteophyte formation. The results can provide further evidence about the efficacy of PRP against KOA progression and can contribute to the current practice of healthcare professionals based on accurate knowledge.

Senso-Immunologic Prospects for Complex Regional Pain Syndrome Treatment

Complex regional pain syndrome (CRPS) is a chronic pain syndrome that occurs in tissue injuries as the result of surgery, trauma, or ischemia. The clinical features of this severely painful condition include redness and swelling of the affected skin. Intriguingly, it was recently suggested that transient receptor potential ankyrin 1 (TRPA1) is involved in chronic post-ischemia pain, a CRPS model. TRPA1 is a non-selective cation channel expressed in calcitonin gene-related peptide (CGRP)-positive primary nociceptors that becomes highly activated in ischemic conditions, leading to the generation of pain. In this review, we summarize the history of TRPA1 and its involvement in pain sensation, inflammation, and CRPS. Furthermore, bone atrophy is also thought to be a characteristic clinical sign of CRPS. The altered bone microstructure of CRPS patients is thought to be caused by aggravated bone resorption via enhanced osteoclast differentiation and activation. Although TRPA1 could be a target for pain treatment in CRPS patients, we also discuss the paradoxical situation in this review. Nociceptor activation decreases the risk of bone destruction via CGRP secretion from free nerve endings. Thus, TRPA1 inhibition could cause severe bone atrophy. However, the suitable therapeutic strategy is controversial because the pathologic mechanisms of bone atrophy in CRPS are unclear. Therefore, we propose focusing on the remission of abnormal bone turnover observed in CRPS using a recently developed concept: senso-immunology.

Ameliorative Effects of Loganin on Arthritis in Chondrocytes and Destabilization of the Medial Meniscus-Induced Animal Model

Arthritis is a common inflammatory disease that causes pain, stiffness, and joint swelling. Here, we investigated the ameliorative effects of loganin on arthritis in vitro and in vivo. A single bioactive compound was fractionated and isolated from Cornus officinalis (CO) extract to screen for anti-arthritic effects. A single component, loganin, was identified as a candidate. The CO extract and loganin inhibited the expression of factors associated with cartilage degradation, such as cyclooxygenase-2 (COX-2), matrix metalloproteinase 3 (MMP-3), and matrix metalloproteinase 13 (MMP-13), in interukin-1 beta (IL-1β)-induced chondrocyte inflammation. In addition, prostaglandin and collagenase levels were reduced following treatment of IL-1β-induced chondrocytes with loganin. In the destabilization of the medial meniscus (DMM)-induced mouse model, loganin administration attenuated cartilage degeneration by inhibiting COX-2, MMP-3, and MMP-13. Transverse micro-CT images revealed that loganin reduced DMM-induced osteophyte formation. These results indicate that loganin has protective effects in DMM-induced mice.