TNFSF11 and chronic obstructive pulmonary disease: Additionally, IL-6 and IL-1 can directly enhance osteoclast activity or indirectly increase RANKL production in osteocytes, further facilitating osteoclast activation and supporting bone resorption mediated by osteoblasts (40) (41) (42) (4).Recent studies have identified a novel mechanism linked to mutations in the GPNMB gene in COPD, which is associated with osteoporosis.