TNF and chronic obstructive pulmonary disease: COPD—Chronic obstructive pulmonary disease, NAFLD—Non-alcoholic fatty liver disease, MI—Myocardial infarction, PGE2- Prostaglandins, MMP—Matrix metalloproteinase, IL—Interleukin, TNF-α—tumor necrosis factor-alpha, CRP—C-reactive protein.