02118nas a2200145 4500000000100000008004100001260003200042100001300074700001500087245006800102856006800170300001000238520171000248022001401958 2021 d bSciencedomain International1 aKadam AD1 aKhopade DM00aStudy of Effect of Nitrosamine Stress in Progression of Leprosy uhttps://journaljpri.com/index.php/JPRI/article/view/31872/59879 a45-503 aObjective: In several countries, including India, leprosy is an older disease & till now continues to be an important health issue. Leprosy is a chronic granulomatous disease, the contributing agent for this is mycobacterium leprae. Nitric oxide (NO) plays a significant role in immunity to fight against bacteria. But increased NO can harm host tissue by causing altered structure of thiol-containing compounds, which is a significant event that influences the pathogenesis of leprosy. Considering this, the study was planned to determine the type of relationship between NO, nitrothiols, and thiols as disease advances. Methods: 50 newly diagnosed leprosy patients & 50 healthy controls were included in the study. In the leprosy group,16 were Paucibacillary (PB), and 34 were Multibacillary (MB) type, leprosy patients. Results: Serum NO and serum nitrothiol significantly increased (p<0.01) in leprosy patients than controls. Further, Serum NO and serum nitrothiol significantly increased (p<0.01) in MB leprosy patients than PB leprosy patients. On the other hand, we found a significantly decreased (p<0.01) level of total thiols in leprosy patients compared with controls. Serum thiols  significantly decreased (p<0.01) in MB leprosy patients than PB leprosy patients. Among Both leprosy patients, the negative correlation of NO with thiol and nitrothiol with thiols was observed. Conclusion: Thus, in leprosy, increased nitric oxide causes modification of thiol groups of proteins and impaired their activity which may be responsible for the severity of disease; hence therapy aimed to reduce nitrosative modification of proteins leprosy. a2456-9119