Krill Oil Attenuates Inflammation in Monosodium Iodoacetate-Induced Osteoarthritic Rats, SW982 Synovial Cell Line, and Primary Chondrocytes

Essential Fatty Acids and Osteoarthritis

OBJECTIVE

Inflammation worsens joint destruction in osteoarthritis (OA) and aggravates pain. Although n-3 fatty acids reduce inflammation, different n-3 fatty acids have different effects on inflammation and clinical outcomes, with eicosapentaenoic acid (EPA) having the strongest effect. We examined whether specific essential fatty acid levels affected the development of OA.

METHODS

We studied participants from the Multicenter Osteoarthritis Study (MOST) at risk of developing knee OA. As part of MOST, participants were asked repeatedly about knee pain, and knee radiographs and magnetic resonance images (MRIs) were obtained. Using baseline fasting samples, we analyzed serum fatty acids with standard assays. After excluding participants with baseline OA, we defined two sets of cases based on their status through 60 months' follow-up: those developing incident radiographic OA and those developing incident symptomatic OA (knee pain and radiographic OA). Controls did not develop these outcomes. Additionally, we examined worsening of MRI cartilage damage and synovitis and worsening knee pain and evaluated the number of hand joints affected by nodules. In regression models, we tested the association of each OA outcome with levels of specific n-3 and n-6 fatty acids, adjusting for age, sex, body mass index, education, physical activity, race, baseline pain, smoking, statin use, and depressive symptoms.

RESULTS

We studied 363 cases with incident symptomatic knee OA and 295 with incident radiographic knee OA. The mean age was 62 years (59% women). We found no associations of specific n-3 fatty acid levels, including EPA, or of n-6 fatty acid levels with incident OA (eg, for incident symptomatic knee OA, the odds ratio per SD increase in EPA was 1.0 [95% confidence interval 0.87-1.17]). Results for other OA outcomes also failed to suggest a protective effect of specific n-3 fatty acids with OA outcomes.

CONCLUSION

We found no association of serum levels of EPA or of other specific n-3 fatty acids or n-6 fatty acids with risk of incident knee OA or other OA outcomes.

Antarctic Krill Oil from Euphausia superba Ameliorates Carrageenan-Induced Thrombosis in a Mouse Model

FJH-KO obtained from Antarctic krill, especially Euphausia superba, has been reported to contain high amounts of omega-3 polyunsaturated fatty acids (n-3 PUFA) and to exhibit anticancer and anti-inflammatory properties. However, its antithrombotic effects have not yet been reported. This study aimed to investigate the antithrombotic effects of FJH-KO in carrageenan-induced thrombosis mouse models and human endothelial cells. Thrombosis was induced by carrageenan injection, whereas the mice received FJH-KO pretreatment. FJH-KO attenuated carrageenan-induced thrombus formation in mouse tissue vessels and prolonged tail bleeding. The inhibitory effect of FJH-KO was associated with decreased plasma levels of thromboxane B2, P-selectin, endothelin-1, β-thromboglobulin, platelet factor 4, serotonin, TNF-α, IL-1β, and IL-6. Meanwhile, FJH-KO induced plasma levels of prostacyclin I2 and plasminogen. In vitro, FJH-KO decreased the adhesion of THP-1 monocytes to human endothelial cells stimulated by TNF-α via eNOS activation and NO production. Furthermore, FJH-KO inhibited the expression of TNF-α-induced adhesion molecules such as ICAM-1 and VCAM-1 by suppressing the NF-κB signaling pathway. Taken together, our study demonstrates that FJH-KO protects against carrageenan-induced thrombosis by regulating endothelial cell activation and has potential as an antithrombotic agent.

Boswellia serrata Extracts Ameliorates Symptom of Irregularities in Articular Cartilage through Inhibition of Matrix Metalloproteinases Activation and Apoptosis in Monosodium-Iodoacetate-Induced Osteoarthritic Rat Models

The research examined the effects of Boswellia serrata extracts (BSE) on a rat model of osteoarthritis induced by monosodium iodoacetate (MIA). The severity and progression of MIA-induced osteoarthritis were assessed using microcomputed tomography imaging. Additionally, the study investigated the impact of BSE various the biomarkers associated with osteoarthritis, including anabolic and catabolic factors, pro-inflammatory factors, and apoptosis factors. The evaluation methods employed included western blot, enzyme-linked immunosorbent assay, and real-time polymerase chain reaction analysis in osteoarthritic rats. Supplementing osteoarthritic rats with BSE reduced tissue injury, cartilage destruction, and decreased in MIA-induced roughness on the articular cartilage surface. MIA-treated rats exhibited increased expressions of phosphorylation of Smad3, MMPs, p-IκB, p-NF-κB, and pro-inflammatory factors (IL-1β, IL-6, TNF-α, and COX-2), which were mitigated by BSE supplementation. Furthermore, protein expressions related to apoptosis pathways were significantly reduced in MIA-induced rats supplemented with BSE. These findings suggested that BSE ingestion may enhance the inflammatory response, decrease JNK-dependent MMPs activation, and alleviate caspase-3-dependent apoptosis in MIA-induced osteoarthritic rat models. Consequently, BSE exhibits potential as a therapeutic agent for treating osteoarthritis.