CCL2 and obesity due to melanocortin 4 receptor deficiency: B/F reduced in the obese mice, while partially corrected by oligofructose; Serum LPS and macrophage increased in the colon of obese mice, while reduced by oligofructose; IL-12 and MCP-1 reduced, IL-10 increased by oligofructose; oligofructose alleviated obesity-related cartilage degeneration.