Dilara Seckin

Antioxidant effect of zinc picolinate in patients with chronic obstructive pulmonary disease

An imbalance between oxidative stress and antioxidant capacity is thought to play an important role in the pathogenesis of chronic obstructive pulmonary disease (COPD). However, studies in regard to stable COPD patients and effect of zinc supplementation are lacking. We investigated the effects of zinc picolinate supplementation on the oxidant stress, and pulmonary function tests (PFTs) of patients with stable COPD. Thirty patients with COPD, and 15 healthy non-smokers who were matched for age and sex were included in the study. Their baseline spirometry, plasma malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), and zinc levels were measured. All parameters were repeated after 8 weeks of supplementation with 22 mg of zinc picolinate daily. The mean MDA levels in the COPD group at baseline were higher than controls (0.51+/-0.15 vs 0.39+/-0.15 nmol/mL, p=0.037), while SOD (0.16+/-0.022 vs 0.20+/-0.04 U/mL, p=0.000), CAT (14.79+/-3.03 vs 17.37+/-2.60k/mL, p=0.008) and zinc levels (77.33+/-4.29 vs 91.45+/-3.95 mg/dL, p=0.000) were lower in the patients compared to controls. Eight weeks of zinc supplementation produced significant increase in mean SOD (p=0.029) and zinc levels (p<0.001). However, no significant change in mean MDA, CAT levels and forced expiratory volume in one second (FEV1) (% predicted), and FEV1/FVC (%) parameters was observed after zinc supplementation. The Pearsons coefficients of correlation between MDA, SOD, CAT, Zn levels and spirometric measurements were not significant on either day 1 nor 8 weeks of zinc supplementation. In conclusion, the results indicate that zinc supplementation may have favorable effects on oxidant-antioxidant balance in patients with COPD. The lack of an effect on PFT may be due to the short duration of the supplementation. Longer duration of zinc supplementation may be necessary to see clinical benefit.

Acute effect of standard heparin versus low molecular weight heparin on oxidative stress and inflammation in hemodialysis patients.

Objective. Atherosclerotic cardiovascular diseases caused by traditional and non-traditional risk factors are the most common cause of morbidity and mortality in hemodialysis patients. Recently, much interest has been focused on non-traditional factors, such as oxidative stress, inflammation, and endothelial dysfunction. Hemodialysis patients are not only exposed to oxidative stress but also to inflammation. Although anticoagulants are the most frequently used drugs in hemodialysis patients, their effect upon oxidative stress and inflammation in dialysis patients are still unknown. Methods. Thirty-three hemodialysis patients were randomized into three groups. Group 1 received standard heparin while group 2 received low molecular weight heparin during the dialysis therapy. Group 3 (control group) did not receive any anticoagulant agent. Investigators were blinded to the therapy. Serum concentrations of oxidative stress and inflammation markers, including C-reactive protein, tumor necrosis factor alpha, superoxide dismutase, and malondialdehyde, were measured before and after dialysis session. Results. The oxidative stress and inflammation markers were significantly increased in groups 1 and 3 (p < 0.05 for each) compared to their baseline values. In contrast, baseline and end-treatment values of the oxidative stress and inflammation markers were comparable in the group 2 (p > 0.05). Conclusion. These findings indicate that the type of anticoagulants may take a role in the acute effect of hemodialysis upon oxidative stress and inflammation markers. A comparison of the groups revealed that low molecular weight heparin decreased the oxidative stress and inflammation, whereas standard heparin increased the oxidative stress and inflammation. Low molecular weight heparin appears to have an additive benefit for hemodialysis patients.

Combined Use of Melatonin and Terazosin Restores Bladder Contractility in Rabbits With Partial Outlet Obstruction

OBJECTIVES To investigate the effects of terazosin and melatonin on isolated rabbit bladder strips after partial bladder outlet obstruction and determine responses to agonist-induced contractility and changes in oxidant-antioxidant system. METHODS We created partial bladder outlet obstruction in 5 groups of rabbits, each containing 8. Rabbits with sham operation (group 1) received no drug treatment. Similarly, animals in group 2 underwent partial bladder outlet obstruction and received no drug treatment. Rabbits in groups 3 were administered 5 mg/day oral terazosin, and rabbits in group 4 received 10 mg/kg/day melatonin intraperitoneally. Animals in group 5 received both terazosin and melatonin. We removed their bladders and performed histopathological and biochemical measurements. We assessed tissue malondialdehyde and antioxidant enzyme activity levels and recorded in vitro contractility response to KCl in isolated organ baths. RESULTS The thickness of muscularis propria was significantly increased in group 2 compared with all other groups. KCl-evoked contractions after partial outlet obstruction were significantly impaired in group 3 and 4 animals receiving terazosin and melatonin, respectively. However, combined use of melatonin and terazosin in group 5 showed contractility responses similar to sham-operated animals (P <0.05). Melatonin administration to groups 4 and 5 showed decreased levels of lipid peroxidation. Similarly, animals receiving melatonin and melatonin plus terazosin showed statistically significant increase in antioxidant enzyme activities. CONCLUSIONS In the present study, we showed that oxidative stress induced by partial bladder outlet obstruction can be successfully antagonized by the potent antioxidant melatonin, and its combined use with an alpha-antagonist such as terazosin may restore in vitro contractility.