TNF and osteoporosis: Although there are many causes of primary osteoporosis, postmenopausal estrogen deficiency is an important cause of osteoporosis in women, and the bone marrow environment releases a variety of cytokines, such as Tumor Necrosis Factor-alpha, Interleukin-1, Interleukin-6, and Receptor Activator Nuclear Kappa-b Ligand, which stimulate and exacerbate bone resorption.[6]