Association between multiple metal(loid)s exposure and renal function: a cross-sectional study from southeastern China

Associations among environmental exposure to trace elements and biomarkers of early kidney damage in the pediatric population

BACKGROUND

In kidney damage, molecular changes can be used as early damage kidney biomarkers, such as Kidney Injury Molecule-1 and Neutrophil gelatinase-associated lipocalin. These biomarkers are associated with toxic metal exposure or disturbed homeostasis of trace elements, which might lead to serious health hazards. This study aimed to evaluate the relationship between exposure to trace elements and early damage kidney biomarkers in a pediatric population.

METHODS

In Tlaxcala, a cross-sectional study was conducted on 914 healthy individuals. The participants underwent a medical review and a socio-environmental questionnaire. Five early damage kidney biomarkers were determined in the urine with Luminex, and molybdenum, copper, selenium, nickel, and iodine were measured with ICP-Mass.

RESULTS

The eGFR showed a median of 103.75 mL/min/1.73 m2. The median levels for molybdenum, copper, selenium, nickel, and iodine were 24.73 ng/mL, 73.35 ng/mL, 4.78 ng/mL, 83.68 ng/mL, and 361.83 ng/mL, respectively. Except for molybdenum and nickel, the other trace elements had significant associations with the eGFR and the early kidney damage biomarkers. Additionally, we report the association of different exposure scenarios with renal parameters.

DISCUSSION

and Conclusions. Among the explored metals, exposure to Cu and iodine impairs renal function. In contrast, Se may manifest as a beneficial metal. Interactions of Mo-Se and Mo-Iodine seem to alter the expression of NGAL; Mo-Cu for CLU; Mo-Cu, Mo-Se, and Mo-iodine for Cys-C and a-1MG; and Mo-Cu and Mo-iodine for KIM-1; were noticed. Our study could suggest that trace element interactions were associated with early kidney damage biomarkers.

Exposure to cadmium and lead is associated with diabetic kidney disease in diabetic patients

BACKGROUND

Cadmium (Cd) and lead (Pb) exhibit nephrotoxic activity and may accelerate kidney disease complications in diabetic patients, but studies investigating the relation to diabetic kidney disease (DKD) have been limited. We aimed to examine the associations of Cd and Pb with DKD in diabetic patients.

METHODS

3763 adults with blood metal measurements and 1604 adults with urinary ones who were diabetic from National Health and Nutrition Examination Survey (NHANES) 2007-2016 were involved. Multivariate logistic regression models were used to analyze the associations of blood Cd (BCd), blood Pb (BPb), urinary Cd (UCd), and urinary Pb (UPb) with DKD.

RESULTS

BPb, BCd, and UCd levels were higher among participants with DKD than diabetics without nephropathy, but UPb performed the opposite result. BPb and UCd were significantly associated with DKD in the adjusted models (aOR, 1.17 (1.06, 1.29);1.52 (1.06, 2.02)). Participants in the 2nd and 3rd tertiles of BPb and BCd levels had higher odds of DKD, with a significant trend across tertiles, respectively (all P-trend < 0.005). Multiplication interaction was also identified for BPb and BCd (P for interaction = 0.044).

CONCLUSION

BPb, BCd, and UCd were positively associated with the risk of DKD among diabetic patients. Furthermore, there were the dose-response relationship and multiplication interaction in the associations of BPb, BCd with DKD.

Association Between Multiple Metal(loid)s Exposure and Blood Lipid Levels: Evidence from a Cross-Sectional Study of Southeastern China

Exposure to essential and toxic metals occurs simultaneously as a mixture in real-life. However, there is no consensus regarding the effects of co-exposure to multiple metal(loid)s (designated hereafter metals) on blood lipid levels. Thus, blood concentrations of six human essential metals and five toxic metals in 720 general populations from southeastern China were simultaneously determined as a measure of exposure. In addition, quantile g-computation, Bayesian kernel machine regression, elastic net regression, and generalized linear model were used to investigate both the joint and individual effects of exposure to this metal mixture on human blood lipid levels. The significant positive joint effect of exposure to this metal mixture on serum total cholesterol (TC) levels, rather than on serum triglycerides, high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol, Castelli risk index I, Castelli risk index II, atherogenic coefficient, and non-HDL-C levels, was found. In addition, the positive effect may be primarily driven by selenium (Se), lead (Pb), and mercury (Hg) exposure. In addition, on the effect of TC levels, the synergistic effect between Pb and Hg and the antagonistic effect between Se and Pb were identified. Our finding suggests that combined exposure to this metal mixture may affect human blood lipid levels. Therefore, reducing exposure to heavy metals, such as Pb and Hg, should be a priority for the general population. In addition, Se supplementation should also be considered with caution.