Plasma advanced glycation end-products and skin autofluorescence are increased in COPD

Abstract

Chronic obstructive pulmonary disease (COPD) is associated with systemic inflammation and oxidative stress. These conditions may lead to the formation of advanced glycation end-products (AGEs).In this study we investigated in 88 COPD patients and 55 control subjects (80% ex-smokers) the association of the plasma protein-bound AGEs N e -(carboxymethyl)lysine (CML), pentosidine, N e -(carboxyethyl)lysine (CEL), and AGE accumulation in skin by skin autofluorescence (AFR), with lung function.Mean¡SD lysine and ex-smokers 27.7¡6.4 nmol?mmol -1 lysine) and AFR (COPD 3.33¡0.67 arbitrary units (AU), never-smokers 2.24¡0.45 AU and ex-smokers 2.31¡0.47 AU) were increased in COPD patients compared to controls. Disease state was inversely associated with CML, and linearly associated with CEL and AFR. Performing regression analyses in the total group, CEL and AFR showed a negative association and CML a positive association with lung function, even after correction for potential confounders.In conclusion, CEL and AFR were negatively and CML was positively associated with disease state. In the total group only the AGEs showed an association with forced expiratory volume in 1 s. Our data suggest that AGEs are involved in the pathophysiology of COPD, although their exact role remains to be determined. @ERSpublications Advanced glycation end-products are involved in the pathophysiology of COPD, but their exact role remains unknown

Cross-sectional associations of pulmonary function with systemic inflammation and oxidative stress in individuals with chronic spinal cord injury

“…Fewer studies have demonstrated cross-sectional associations with biomarkers of oxidative stress. [18][19][20][21][22] Similar findings in populations with and without COPD suggest that the mechanisms responsible are not likely to be solely mediated by pulmonary inflammation, but may be related to other sources of systemic inflammation and oxidative stress. Chronic spinal cord injury (SCI) is characterized by abnormal pulmonary function as a consequence of respiratory system changes secondary to respiratory muscle weakness and paralysis, but is not known to result in pulmonary inflammation.…”

“…21 In 88 Dutch patients with moderate-to-severe COPD and 55 controls, the associations of percent-predicted FEV 1 with a number of measures of advanced glycation end-products were examined, with mixed results. In models adjusted for age, sex, person-years of smoking, BMI, HDL cholesterol, triglycerides, glomerular filtration rate, and CRP, N 6 -(carboxyethyl)lysine and skin autofluorescence were negatively associated and N 6 -(carboxymethyl)lysine was positively associated with percent-predicted FEV 1 , and the authors concluded that the exact role of these glycation end products remains to be determined.…”

Pathways of the Maillard reaction under physiological conditions

“…[a] isomerization, unknown ox. fragmentation various tissues, plasma, blood cells, urine, faecis, lens, reviewed in [89,90] N 6 -carboxyethyl lysine (CEL) [a] isomerization plasma [76,[91][92][93]; plasma, blood cells, urine [54,94]; lens [77,95] glycolic acid lysine amide (GALA) [b] isomerization lens [77] N 6 -formyl lysine [b] amine induced β-cleavage plasma [76], lens [77] N 6 -acetyl lysine [b] amine induced β-cleavage plasma [76], lens [77] N 6 -oxalyl lysine [b] ox. α-cleavage, amine induced β-cleavage lens [77] N 6 -lactoyl lysine [b] amine induced β-cleavage plasma [76]; lens [77] N 6 -glycerinyl lysine [b] amine induced β-cleavage plasma [76] N 6 -threonyl lysine [b] ox.…”

The analysis of advanced glycation endproducts

“…This was in reasonable agreement with data described in literature [36][37][38][39][40][41] . The described method is suitable for studying AGEs in several different human and animal studies [42][43][44][45][46][47][48][49] and is a strong tool to investigate the putative effects of AGEs in the pathophysiology of different diseases.…”

“…The reduction of glucose to sorbitol and further oxidation to fructose and fructose-3-phosphate leads to the formation of 3-DG. Thus, AGEs can be formed by these sugar-derived carbonyls 45 , by lipid peroxidation and oxidative stress 46,47 or by reactions between pentoses and proteins, known as the fluorescent lysine-arginine cross-link pentosidine 36,48 .…”