Comparative assessment of essential and toxic metals in the blood of rheumatoid arthritis patients and healthy subjects

Environmental pollution impact on the severity of some rheumatic diseases: a comparative analytical study on inflammatory and non-inflammatory samples

OBJECTIVE

Environmental pollution of heavy metals is increasingly a problem and has become of great concern due to the adverse effects it causes worldwide. Heavy metal exposure has been implicated in health problems, including fibromyalgia and rheumatoid arthritis. We aim to evaluate the rule of chronic heavy metals toxicity on the induction of vitamin D3 (VD) deficiency and parathyroid hormone (PTH) disturbances in an inflammatory disease like rheumatoid arthritis (RA) and non-inflammatory disease like fibromyalgia syndrome (FMS).

METHODS

This comparative analytical study was conducted on sixty adults (age ≥ 18 years). Participants were divided into three groups. Group I: twenty patients diagnosed with RA according to the specific ACR/EULAR criteria for RA. Group II: twenty patients diagnosed with FMS according to the specific 2010 (ACR) criteria for FMS. Group III: twenty healthy adults. All patients and controls were subjected to routine laboratory tests as well as the measurement of PTH, VD and estimation of serum levels of lead, cadmium, and chromium.

RESULTS

VD was significantly inversely correlated to PTH, lead, cadmium, chromium, and activity scores in the RA and FMS groups. Lead, Cadmium and Chromium had a significant independent risk on the VD level in RA patients, while lead had a significant independent risk on the VD level in FMS patients.

CONCLUSION

Heavy metals may affect VD synthesis, leading to hypovitaminosis D and secondary hyperparathyroidism in RA and FMS patients. Heavy metals play a key role in the pathogenesis of RA, FMS, and their disease activity.

Identification of lead-binding proteins as carriers and potential molecular targets associated with systolic blood pressure

Lead (Pb) exposure is well recognized as a significant environmental factor associated with the high incidence of cardiovascular diseases. However, the carriers and molecular targets of Pb in human blood remain to be understood, especially for a real Pb exposure scenario. In this study, a total of 350 blood samples were collected from the smelting workers and systematically analyzed using metallomics and metalloproteomics approaches. The results showed that the majority of Pb (∼99.4%) could be presented in the blood cells. Pb in the cytoplasm of blood cells accounted for approximately 83.1% of the total blood Pb, with nearly half of Pb being bound to proteins. Pb-binding proteins in the blood of workers were identified as hemoglobin, catalase, haptoglobin, δ-aminolevulinic acid dehydratase, and peroxiredoxin-2. Multiple linear regression analysis demonstrated that higher levels of Pb bound to proteins (Mix-bound Pb and Protein-bound Pb) were positively associated with higher systolic blood pressure (p < 0.05). However, the association between blood lead level, Pb levels in the blood cells and systolic blood pressure was not observed (p > 0.05). This study suggested that Pb bound to proteins could be a suitable biomarker for indicating the potential risk of occupational hypertension.

Evaluation of some trace elements and antioxidants in sera of patients with rheumatoid arthritis: a case-control study

INTRODUCTION

Rheumatoid arthritis (RA) is a chronic autoimmune inflammatory disease that destroys joints. The concentrations of elements (Zn, Cu, Mg, Mn, Fe, Ni, Cr, K, Na, Ca, Pb, and Cd), as well as antioxidant glutathione GSH and lipid peroxidation marker malondialdehyde MDA, will be determined in this study.

METHOD

The study involves 120 female RA patients and 60 healthy females in the control group, all of whom are between the ages of 20 and 60. Patients having diabetes, hypertension, hyperthyroidism, or psoriasis, in addition to RA, were excluded.

RESULTS

When RA patients were compared to healthy individuals, the levels of Cu, Ni, Na, Pb, and Cd were significantly higher (p < 0.01), whereas the levels of Zn, Mg, Mn, Cr, Ca, K, and Fe were significantly lower (p < 0.01). The Cu/Zn (2.21 and 1.16) and Na/k (38.67 and 34.87) ratios were also found to be significantly higher in RA patients compared to controls. Furthermore, the data indicated that GSH concentrations in RA patients were significantly lower (p < 0.01) than those in controls (655.90 and 1345.17 mol/l, respectively). MDA levels in RA patients were significantly higher (p < 0.01) than those in controls (2.739 and 1.673 mol/l, respectively).

CONCLUSIONS

The data indicate that Cu/Zn and Na/k ratios can be of great value in the diagnosis and evaluation of RA patients. On this basis, we conclude that these elements can be relied upon to provide indications of RA risk and the measurement of oxidative stress can serve as a biomarker to monitor disease activity and severity in RA patients. Key Points • Trace elements may be of value and may have an expected significance in the early diagnosis, prognosis, and treatment evaluation of rheumatoid arthritis. • The distortion in the levels of trace elements may reflect their possible role in the pathogenesis of rheumatoid arthritis. • Oxidative stress can act as a biomarker to monitor disease activity and severity in patients with rheumatoid arthritis. • The trace elements can contribute to the manifestation of inflammatory diseases due to their role in the synthesis of some antioxidants or due to their effect on the immune system.

Impact of Cadmium Mediated by Tobacco Use in Musculoskeletal Diseases

Tobacco use has a negative impact on health due to its relationship with the development of high-mortality diseases, such as pulmonary cancer. However, the effect of cadmium (Cd), present in tobacco smoke, on the development of joint diseases has been scarcely studied. The objective of this review is to discuss the evidence regarding the mechanisms by which Cd exposure, through tobacco smoke, may lead to the development of osteoarthritis (OA), osteoporosis (OP), and rheumatoid arthritis (RA). There's evidence suggesting a string association between moderate to severe OA development and tobacco use, and that a higher blood concentration of Cd can trigger oxidative stress (OS) and inflammation, favoring cartilage loss. At the bone level, the Cd that is inhaled through tobacco smoke affects bone mineral density, resulting in OP mediated by a decrease in the antioxidant enzymes, which favors the bone resorption process. In RA, tobacco use promotes the citrullination process through Cd exposure and increases OS and inflammation. Understanding how tobacco use can increase the damage at the articular level mediated by a toxic metal, i.e., Cd, is important. Finally, we propose prevention, control, and treatment strategies for frequently disabling diseases, such as OA, OP, and RA to reduce its prevalence in the population.

Serum Cesium, Rhenium, and Rubidium in Rheumatoid Arthritis Patients

A considerable attention has been focused on the possible association between ultra-trace elements (UTEs) status and pathogenesis of many diseases including rheumatoid arthritis (RA). UTEs have important roles in numerous metabolic processes. Serum Cs, Rb, and Re levels in RA are not studied previously. The correlation of serum Cs, Rb, and Re levels with the well-known serological parameters, anticyclic citrullinated protein antibody (ACPA), C-reactive protein (CRP), ESR, and rheumatoid factor (RF) is also not studied previously. The present study aimed to measure the level and the correlation between serum UTEs with various blood tests results in RA patients. Serum Cs, Rb, Re, ACPA, CRP, RF, and ESR were measured in Iraqi RA patients who have a positive ACPA (ACPA > 25 U/ml) and compared with healthy individuals. There were significant elevations (p < 0.05) in serum levels of all the measured parameters as compared with those of the healthy control group except Rb and uric acid which have not been changed. Subgrouping of patients according to the results of CRP and RF leads to different results. In the low-CRP group, the high-RF subgroup showed an elevation of ACPA, Cs, and ESR in comparison with the low-RF patients. In the high-CRP group, the patients with high RF showed an increase in the levels of Cs, Rb, ESR, and ACPA. The patient group with high RF and high CRP showed more significant correlations between serum UTEs and serological tests. Serum levels of UTEs were significantly altered in RA patients. The variations in the serum levels of the measured parameters in RA need more investigation to explore the possible association between these UTEs and RA. RA subgroups, according to the results of CRP and CPA, produce more and various information than taking RA as a whole group in the estimation of UTEs.

Statistical evaluation of essential/toxic metal levels in the blood of valvular heart disease patients in comparison with controls

The present study was designed to investigate the role of selected essential and toxic metals in the onset/prognosis of valvular heart disease (VHD). Nitric acid-perchloric acid based wet digestion procedure was used for the quantification of the metals by flame atomic absorption spectrophotometry. Comparative appraisal of the data revealed that average levels of Cd, Co, Cr, Fe, K, Li, Mn and Zn were significantly higher in blood of VHD patients, while the average concentration of Ca was found at elevated level in controls (P < 0.05). However, Cu, Mg, Na, Sr and Pb depicted almost comparable levels in the blood of both donor groups. The correlation study revealed significantly different mutual associations among the metals in the blood of VHD patients compared with the controls. Multivariate statistical methods showed substantially divergent grouping of the metals for the patients and controls. Some significant differences in the metal concentrations were also observed with gender, abode, dietary/smoking habits and occupations of both donor groups. Overall, the study demonstrated that disproportions in the concentrations of essential/toxic metals in the blood are involved in pathogenesis of the disease.

ICPMS analysis of proteins separated by Native-PAGE: Evaluation of metaloprotein profiles in human synovial fluid with acute and chronic arthritis

The role of trace elements bound to proteins in the etiology and pathogenesis of rheumatoid arthritis (RA) remains unclear. In this sense, the identification and detection of metalloproteins has a strong and growing interest. Metalloprotein studies are currently carried out by polyacrylamide gel electrophoresis (PAGE) associated to inductively coupled plasma mass spectrometry (ICPMS), and despite that complete information can be obtained for metals such as Fe, Cu and Zn, difficulties due to poor sensitivity for other trace elements such as Sn, As, etc, are currently faced. In the present work, a simple and fast method for the determination of trace metals bound to synovial fluid (SF) proteins was optimized. Proteins from SF (long and short-term RA) were separated in ten fractions by native PAGE, then dissolved in nitric acid and peroxide hydrogen, and analyzed by ICPMS. Fifteen metals were determined in each separated protein fraction (band). Adequate calibration of proteins molecular weight allowed stablishing which protein type were bound to different metals.

Association between serum trace element concentrations and the disease activity of systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is an autoimmune disease with a complex, incompletely understood, etiology. Several genetic and environmental factors are suspected to be involved in its aetiology. Oxidative stress may be implicated in the pathogenesis of SLE and may be affected by trace element status. Zinc (Zn), copper (Cu) and selenium (Se) are essential components of several anti-oxidative enzymes and are also involved in several immune functions. The current study aimed to assess the relationship between serum concentrations of these trace elements and the clinical disease activity of SLE assessed using the SLE disease activity index (SLEDAI). Serum concentrations of albumin (Alb) (p = 0.001), Se (p = 0.001), Zn (p = 0.001) and the Zn to Cu ratio (Zn/Cu R) (p = 0.001) were lower in patients with SLE than the age- and sex-matched healthy controls. However, only Alb (p = 0.001) and Cu (p = 0.03) were negatively correlated with disease activity, which was supported by regression analysis. In summary, lower serum values of Alb, Zn, Se and Zn/Cu R were found in SLE patients compared with healthy controls; however, in addition to serum Alb concentrations, serum Cu concentrations were also negatively correlated with lupus disease activity.