Increasing levels of serum antioxidant status, total antioxidant power, in systemic sclerosis

Abstract

Sciences Running title: Total antioxidant power levels in SScKey words: systemic sclerosis, oxidative stress, total antioxidant power, biomarker Methods: Serum TAP levels were examined in 49 patients with SSc by colorimetric microplate assay. The assay measures the total abilities for reducing Cu++ into Cu+.Clinical evaluation including medical history, physical examination, and laboratory tests were conducted for all SSc patients.Results: Serum TAP levels were significantly elevated in SSc patients compared to normal controls (p<0.01). When values higher than the mean + 2SD of the control serum samples were considered to be elevated, TAP levels were elevated in 24% of total SSc patients with 26% of diffuse cutaneous SSc patients and 23% of limited cutaneous SSc patients. Serum TAP levels were correlated positively with C-reacting protein (r=0.35, p<0.05). However, no other significant correlation was observed between serum TAP levels and clinical features in SSc patients. Conclusion:These results suggested that oxidative stress is enhanced in SSc patients and serum TAP levels increase as an indicator of the global response to oxidative stress.

High reactive oxygen species in fibrotic and nonfibrotic skin of patients with diffuse cutaneous systemic sclerosis

“…This protein was found to be significantly elevated in serum of patients with SSc compared to healthy controls with no differences between lcSSc and dcSSc patients. [28] The same group have also shown that as a result of oxidative stress, in SSc patients with either limited or diffuse form SSc, had elevated total antioxidant power (TAP) when compared with healthy controls, with no significant difference between limited or diffuse forms [15]. A…”

“…ROS levels, in particular superoxide levels, were higher in dermal fibroblasts obtained from the skin of patients with dcSSc compared to normal cells [13]. On the other hand, some investigators have shown an abnormal antioxidant status in scleroderma patients, demonstrating either high detoxifying enzymes (Erythrocyte glutathione transferase, eGST) [14] or high Total Antioxidant Power (TAP) [15] in these patients. Conversely, non-enzymatic antioxidants such as ascorbic acid (vitamin C), α-tocopherol, β-carotene, and selenium were also shown to be reduced in plasma of patients with SSc [8,16].…”

“…An imbalance between the elevated levels of ROS/RNS and/or the impaired function of the antioxidant defence system is known as oxidative stress [8]. In SSc, elevation of oxidative stress "markers" or alteration of antioxidant mechanisms have been described by many investigators [8,[12][13][14][15][16][17][18].…”

Role of Oxidative Stress and Reactive Oxygen Radicals in the Pathogenesis of Systemic Sclerosis

“…Indeed, reduction of endogenous antioxidants and a parallel overproduction of reactive oxygen species (ROS) have been documented in SSc, although increased generation or overproduction of ROS appears to be the main mechanism whereas ROS inactivation is believed to play a less important role. Several studies demonstrated decreased levels of antioxidants in serum of SSc patients [ 8,9 ] although other studies have not con fi rmed these observations [ 10 ] . Furthermore, numerous others have shown increased ROS production [11][12][13][14] providing strong evidence to the important contribution of oxidative stress in the pathogenesis of the disease.…”

The oxidative stress parameters and the effect of dyslipidemia on the parameters of oxidative stress in lichen planus

“…LP'nin etiyopatogenezi halen bilinmemektedir. Kronik enflamatuvar pek çok hastalıkta kronik enflamasyon ve oksidatif stresin rolünün olduğuna dair çalışmalar bildirilmiştir [5][6][7][8][9] . Kronik bir hastalık olan LP' de oksidatif stresin rolü araştırıldığında ise ilgili yayınların çoğunlukla oral LP ile ilişkili olduğu gözlenmiştir [10][11][12][13] .…”