 Obesity is associated with a higher risk of developing osteoarthritis, OA. This study examined how obesity affects the joint environment and how it leads to OA. It was found that obesity causes an increase in macrophages in the joint which are responsible for inflammation and damage to the joint. Additionally, these macrophages have a lower ability to engulf and clear away dead cells from the joint, leading to further damage. Finally, this study suggests that injecting gas 6 into the joint can help reduce the number of macrophages and improve the ability of macrophages to clear away dead cells, thus reducing the severity of OA. This article was authored by Zihao Yao, Wei Zhongqi, Hong Bojong, and others.