Abstract： In serum,adiponectin can exist as either full-length form that can form trimers,hexamers and high molecular weight (HMW) multimers,or as globular adiponectin (gAd).Adiponectin-deficiency leads to an increase in proinflammatory mediators and an emphysemalike phenotype,1 also protects against tobacco-induced inflammation and the increased emphysema.2 The mechanism underlying this apparent paradox remains unclear.We therefore analyzed serum levels of adiponectin isoforms,thioredoxin (Trx)/thioredoxin reductase (TrxR) activity,tumor necrosis factor (TNF)-α,IL-6and 4-hydroxynonenal (4-HNE) in patients with chronic obstructive pulmonary disease (COPD) and in control individuals.