The Divalent Elements Changes in Early Stages of Chronic Kidney Disease

Chronic kidney disease: a contraindication for using biodegradable magnesium or its alloys as potential orthopedic implants?

Magnesium (Mg) has gained widespread recognition as a potential revolutionary orthopedic biomaterial. However, whether the biodegradation of the Mg-based orthopedic implants would pose a risk to patients with chronic kidney disease (CKD) remains undetermined as the kidney is a key organ regulating mineral homeostasis. A rat CKD model was established by a 5/6 subtotal nephrectomy approach, followed by intramedullary implantation of three types of pins: stainless steel, high pure Mg with high corrosion resistance, and the Mg-Sr-Zn alloy with a fast degradation rate. The long-term biosafety of the biodegradable Mg or its alloys as orthopedic implants were systematically evaluated. During an experimental period of 12 weeks, the implantation did not result in a substantial rise of Mg ion concentration in serum or major organs such as hearts, livers, spleens, lungs, or kidneys. No pathological changes were observed in organs using various histological techniques. No significantly increased iNOS-positive cells or apoptotic cells in these organs were identified. The biodegradable Mg or its alloys as orthopedic implants did not pose an extra health risk to CKD rats at long-term follow-up, suggesting that these biodegradable orthopedic devices might be suitable for most target populations, including patients with CKD.

Role of Nutrients in Pediatric Non-Dialysis Chronic Kidney Disease: From Pathogenesis to Correct Supplementation

Nutrition management is fundamental for children with chronic kidney disease (CKD). Fluid balance and low-protein and low-sodium diets are the more stressed fields from a nutritional point of view. At the same time, the role of micronutrients is often underestimated. Starting from the causes that could lead to potential micronutrient deficiencies in these patients, this review considers all micronutrients that could be administered in CKD to improve the prognosis of this disease.

The association between urinary metals/metalloids and chronic kidney disease among general adults in Wuhan, China

The relation between exposure to single metal/metalloid and the risk of chronic kidney disease (CKD) remains unclear. We aimed to determine the single and mixed associations of 21 heavy metals/metalloids exposure and the risk of CKD. We performed a cross-sectional study that recruited 4055 participants. Multivariate logistic regression, linear regression and weighted quantile sum (WQS) regression were conducted to explore the possible effects of single and mixed metals/metalloids exposure on the risk of CKD, the risk of albuminuria and changes in the estimated glomerular filtration rate (eGFR). In single-metal models, Cu, Fe, and Zn were positively associated with increased risks of CKD (P-trend < 0.05). Compared to the lowest level, the highest quartiles of Cu (OR = 2.94; 95% CI: 1.70, 5.11; P-trend < 0.05), Fe (OR = 2.39; 95% CI: 1.42, 4.02; P-trend < 0.05), and Zn (OR = 2.35; 95% CI: 1.31, 4.24; P-trend < 0.05) were associated with an increased risk of CKD. After multi-metal adjustment, the association with the risk of CKD remained robust for Cu (P < 0.05). Weighted quantile sum regression revealed a positive association between mixed metals/metalloids and the risk of CKD, and the association was largely driven by Cu (43.7%). Specifically, the mixture of urinary metals/metalloids was positively associated with the risk of albuminuria and negatively associated with eGFR.

A thorough screening based on QTLs controlling zinc and copper accumulation in the grain of different wheat genotypes

Excess trace metals may cause damage to human health due to the consumption of food grain grown in contaminated soils. This study was designed to understand the genetic mechanisms of copper (Cu) and zinc (Zn) accumulation in wheat grain under stressed environments. The differences of Cu/Zn contents in the grain among 246 wheat varieties were analyzed, and the wheat varieties with low or high accumulation of Cu and Zn in the safe range were also screened out. The accumulation of Cu and Zn in grains of "Chushanbao" was lowest, which could be used as a novel germplasm for wheat breeding under heavy metal stress. We found that Cu contents of wheat grain were significantly and positively correlated with Zn. The quantitative trait loci (QTLs) for grain Cu content (GCuC) and grain Zn content (GZnC) were detected by genome-wide association study (GWAS). Twenty-three loci affecting GCuC were identified on chromosomes 1A, 1D, 2A, 2B, 2D, 3A, 3B, 3D, 4A, 4B 4D, 5A, 6D, 7A, and 7B, explaining 2.6-5.8% of the phenotypic variation. Sixteen loci associated with the GZnC on 11 different chromosomes 1B, 2B, 2D, 3A, 3D, 4A, 4B, 5A, 5D, 6B, and 7D were detected, which could explain 2.7~6.6% of phenotypic variance. We also determined five associated loci on chromosomes 2B, 2D, 3A, 4B, and 5A were in pleiotropic regions affecting both GCuC and GZnC. This study would help in better understanding the molecular basis of Cu/Zn accumulation in wheat grain, and the associated markers may be useful for marker-assisted selection (MAS) breeding program.

Environment-Based Impairment in Mineral Nutrient Status and Heavy Metal Contents of Commonly Consumed Leafy Vegetables Marketed in Kyrgyzstan: a Case Study for Health Risk Assessment

Leafy vegetables are important components of the human diet for providing mineral nutrients. However, due to the tendency of metal accumulation, metal contents of leafy vegetables need not only to be determined but also estimated health risk for revealing possible health effects on humans. The aims of this study are (I) to examine comprehensive concentrations of trace/heavy metals along with some macroelements including Ca, Cd, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, and Zn in selected leafy vegetables from Kyrgyzstan; (II) to assess recommended dietary allowances (RDA); and (III) to evaluate hazard quotient (HQ) and carcinogenic risk estimation with associated vegetable consumption. For this purpose, B, Ca, Cd, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, and Zn elements were quantified, utilizing an ICP-OES instrument, in 18 samples belonging to 12 different groups of leafy vegetables including celery, Chinese parsley, dill, garden sorrel, lettuce, parsley, purple basil, spinach, and white-red-napa cabbage collected from different bazaars of Kyrgyzstan. Average elemental contents of the analyzed vegetables were determined (in mg kg^-1) as follows: B (3.21-64.79), Ca (852.51-17,183.20), Cd (0.015-0.09), Cu (6.08-63.47), Fe (116.52-768.66), K (2347.04-17,305.42), Mg (136.34-1261.11), Na (54.75-526.42), Ni (0.09-1.3), Pb (1.91-9.54), and Zn (29.49-314.93). Estimated daily intake, recommended daily allowance, hazard quotients, and carcinogenic risk values of the vegetables were calculated with the help of these results. In considering HQ values, Chinese cabbage was determined to be safe for the consumption of both genders whereas parsley to be safe for only males. Based on the carcinogenic risk calculation, most of the vegetables examined in this study were categorized as moderately risky. It was inferred from the given results that airborne pollution has impaired/increased the mineral contents of vegetables for both genders. The findings obtained from this study were compared with international standards and will contribute to the data available on a global scale.

Toll-like Receptors as Potential Therapeutic Targets in Kidney Diseases

Toll-like Receptors (TLRs) are members of pattern recognition receptors and serve a pivotal role in host immunity. TLRs response to pathogen-associated molecular patterns encoded by pathogens or damage-associated molecular patterns released by dying cells, initiating an inflammatory cascade, where both beneficial and detrimental effects can be exerted. Accumulated evidence has revealed that TLRs are closely associated with various kidney diseases but their roles are still not well understood. This review updated evidence on the roles of TLRs in the pathogenesis of kidney diseases including urinary tract infection, glomerulonephritis, acute kidney injury, transplant allograft dysfunction and chronic kidney diseases.

Urinary magnesium predicts risk of cardiovascular disease in Chronic Kidney Disease stage 1-4 patients

Observational studies on dietary or circulating magnesium and risk of cardiovascular disease (CVD) in Chronic Kidney Disease (CKD) stage 1-4 have reported no-to-modest inverse associations. 24 h Urinary magnesium concentration (24 h UMg), an indicator of intestinal magnesium absorption, may provide better insight into the connection of CKD progression. We examined 3179 participants aged 18-74 years with CKD stage 1-4 in the Chinese Cohort Study of Chronic Kidney Disease (C-STRIDE) study, a prospective population-based cohort study. Data were analysed using Spearman rank-order correlation coefficients for all comparisons. We also performed a time-to-event analysis of the data using the Kaplan-Meier survival model, Cox proportional hazard model and competing risk Fine and Gray subdistribution hazard model. During a median follow-up of 4.19 years (interquartile range, 3.43-5.09 years), when modelling end-stage renal disease (ESRD), CVD and death, 24 h UMg was associated with risk of CVD (HR, 1.612 (95% CI, 1.056-2.460)), while no significant association with ESRD and death endpoints could be detected. 24 h UMg risk variants display a modest association with CVD in CKD stage 1-4 patients. TRIAL REGISTRATION: ClinicalTrials.gov Identifier NCT03041987. Registered January 1, 2012. (retrospectively registered) (https://www.clinicaltrials.gov/ct2/show/NCT03041987?term=Chinese+Cohort+Study+of+Chronic+Kidney+Disease+%28C-STRIDE%29&rank=1).

Changes in Trace Elements During Early Stages of Chronic Kidney Disease in Type 2 Diabetic Patients

Trace elements can influence glucose metabolism and be related to oxidative stress in type 2 diabetes mellitus. Moreover, trace elements play important roles in the nephrotic complications of these patients. Nevertheless, few investigations have been made into the changes in the levels of trace elements in diabetic patients at various stages of chronic kidney disease (CKD). The aims of this present study were to determine the levels of some important trace elements in diabetic patients during the early stages of CKD and to identify the relationship between these elements and CKD progression in type 2 diabetic patients. One hundred and forty-eight type 2 diabetic patients with chronic kidney diseases were recruited into this study. The subjects were grouped into four stages (1, 2, 3a, 3b) of CKD, according to their urine protein levels and estimated glomerular filtration rates (eGFRs). The levels of serum zinc and iron exhibited a statistically significant decreasing trend (P trend = 0.032 and 0.047, respectively) from stage 1 to stage 3b after adjustment for age, gender, smoking, alcohol consumption, education, hypertension, and body mass index. The other tested elements, including copper, magnesium, selenium, chromium, and manganese, did not display any significant trends upon proceeding from stage 1 to stage 3b. Thus, serum zinc and iron appear to be useful markers when evaluating the early progression of CKD in type 2 diabetic patients.