This study is a clinical trial that designed to assess effect of Pioglitazone in improving respiratory and inflammatory markers in 15 patients (18-75) with diabetes and asthma referred to Yazd Diabetic Research Center. Inclusion criteria: aged between 18 and 50 years, diagnosing asthma at least one year, HbA1C between 8-9, positive test of methacholine or bronchodilator, treated with inhaled corticosteroid at least three months with or without long-acting inhaled bronchodilator, radiography do not show other diseases. Exclusion criteria: hypersensitivity to pioglitazone, receiving oral steroids, smoking during the past three months, respiratory infections within a month before the start of the study , history of pulmonary diseases besides asthma, more than 2+ edema, heart failure, osteopenia or osteoporosis (T-score <-1). Patients will be given pioglitazone tablet 30 microgram daily for three months. markers such as Leptin, CRP and breathing markers such as FEV1 and ratio of FEV1/FVC and exhaled NO before and after treated will be measured.