Correlation of plasma NEFA levels, cartilage p65 activity, chondrocyte miR-26a and TNF-α levels with the BMI in the patients with osteoarthritis
(A) Correlation of plasma NEFA levels with the BMI in the patients with osteoarthritis (n=12). Pearson's correlations: R=0.74, and P< 0.05. (B) Correlation of p65 activity (calculated by the ratio of p-p65/p65 in immunoblotting assay) in the cartilages with the BMI in the patients with osteoarthritis (n=12). Pearson's correlations: R=0.93, and P< 0.05. (C) Correlation of miR-26a levels in the chondrocytes with the BMI in the patients with osteoarthritis (n=12). Pearson's correlations: R=0.78, and P< 0.05. (D) Correlation of TNF-α mRNA levels in the chondrocytes with the BMI in the patients with osteoarthritis (n=12). Pearson's correlations: R=0.71, and P< 0.05. (E) Proposed models for reciprocal inhibition between miR-26a and NF-κB regulating obesity-associated chronic inflammation in chondrocytes. Briefly, miR-26a exerts inhibitory effect on NF-κB activity and proinflammatory cytokine production in chondrocytes. In obesity, elevated NEFA in circulation might stimulate NF-κB activity, which suppresses miR-26a production and further potentiates the production of proinflammatory cytokines. Those elevated proinflammatory cytokines from the chondrocytes aggravate the inflammation in cartilage, perhaps inducing osteoarthritis.