Serum Levels of Copper and Zinc in Patients with Rheumatoid Arthritis: a Meta-analysis

Abstract

Many publications with conflicting results have evaluated serum levels of copper (Cu) and zinc (Zn) in patients with rheumatoid arthritis (RA). To derive a more precise estimation of the relationship, a meta-analysis was conducted. Relevant published data were retrieved through PubMed, Chinese National Knowledge Infrastructure (CNKI), and Chinese Biomedical Database (CBM) before September 20, 2014. Weighted mean difference (WMD) with a 95 % confidence interval (95 % CI) was calculated using STATA 11.0. A total of 26 studies, including 1444 RA cases and 1241 healthy controls, were collected in this meta-analysis. Pooled analysis found that patients with RA had a higher serum level of Cu and a lower serum Zn level than the healthy controls (Cu (μg/dl), WMD = 31.824, 95 % CI = 20.334, 43.314; Zn (μg/dl), WMD = -12.683, 95 % CI = -19.783, -5.584). Subgroup analysis showed that ethnicity had influence on the serum level of Cu (μg/dl) (Caucasian, WMD = 43.907, 95 % CI = 35.090, 52.723, P < 0.001; Asian, WMD = 14.545, 95 % CI = -12.365, 41.455, P = 0.289) and Zn (μg/dl) (Caucasian, WMD = -11.038, 95 % CI = -23.420, 1.344, P = 0.081; Asian, WMD = -14.179, 95 % CI = -18.963, -9.394, P < 0.001) in RA and healthy controls. No evidence of publication bias was observed. This meta-analysis suggests that increased serum level of Cu and decreased serum level of Zn are generally present in RA patients.

Expansion of Rare and Harmful Lineages is Associated with Established Rheumatoid Arthritis

“…Although none of these mechanisms were explicitly examined in our study, PICRUSt analysis demonstrated that, compared with controls, the patient's microbiota facilitates copper transport and inhibits zinc transport. This finding may explain the higher copper levels and the lower zinc levels found in RA patients than in healthy subjects [45]. These trace elements are essential to many human biological processes, since they play a role in the functionality of enzymes and post-translational regulatory protein [46], with significant effects on cell regulation in both the adaptive and the innate immune systems.…”

RETRACTED ARTICLE: Regulation function of MMP-1 downregulated by siRNA on migration of heat-denatured dermal fibroblasts

“… 18 Many biological factors have been indicated to act as potent post-transcriptional repressors of collagen synthesis in skin fibroblasts and have been shown to be potential therapeutic targets for scar reduction. 19,20 …”

Zinc Signals and Immunity

“…Its significance as a structural component in proteins [ 2 ] and its participation in numerous cellular functions include, but are not limited to, cell proliferation and differentiation [ 3 , 4 ], RNA and DNA synthesis [ 5 , 6 ], stabilization of cell structures/membrane [ 7 , 8 ], as well as redox regulation [ 9 , 10 ], and apoptosis [ 11 , 12 ]. Zinc is involved in various metabolic and chronic diseases such as: type 1 diabetes, rheumatoid arthritis, cancer, neurodegenerative diseases, and depression [ 13 , 14 , 15 , 16 , 17 , 18 , 19 ]. Moreover, there is also strong evidence between zinc deficiency and several infectious diseases such as shigellosis, acute cutaneous leishmaniosis, malaria, human immunodeficiency virus (HIV), tuberculosis, measles, and pneumonia [ 20 , 21 ].…”