PARP1 and chronic obstructive pulmonary disease: As far COPD is accompanied by systemic OS, the effect of novel tetrapeptide analogue of glutathione (GSH), UPF17 (4-methoxy-L-tyrosinyl-α-L-glutamyl-L-cysteinyl-glycine) on the PARP-1 activity through changing mRNA expression of PARP-1 was measured.