Determination of serum aluminum, platelet aggregation and lipid peroxidation in hemodialyzed patients

Toxicity and biokinetics following pulmonary exposure to aluminium (aluminum): A review

During the manufacture and use of aluminium (aluminum), inhalation exposure may occur. We reviewed the pulmonary toxicity of this metal including its toxicokinetics. The normal serum/plasma level based on 17 studies was 5.7 ± 7.7µg Al/L (mean ± SD). The normal urine level based on 15 studies was 7.7 ± 5.3µg/L. Bodily fluid and tissue levels during occupational exposure are also provided, and the urine level was increased in aluminium welders (43 ± 33µg/L) based on 7 studies. Some studies demonstrated that aluminium from occupational exposure can remain in the body for years. Excretion pathways include urine and faeces. Toxicity studies were mostly on aluminium flakes, aluminium oxide and aluminium chlorohydrate as well as on mixed exposure, e.g. in aluminium smelters. Endpoints affected by pulmonary aluminium exposure include body weight, lung function, lung fibrosis, pulmonary inflammation and neurotoxicity. In men exposed to aluminium oxide particles (3.2µm) for two hours, lowest observed adverse effect concentration (LOAEC) was 4mg Al2O3/m3 (= 2.1mg Al/m3), based on increased neutrophils in sputum. With the note that a similar but not statistically significant increase was seen during control exposure. In animal studies LOAECs start at 0.3mg Al/m3. In intratracheal instillation studies, all done with aluminium oxide and mainly nanomaterials, lowest observed adverse effect levels (LOAELs) started at 1.3mg Al/kg body weight (bw) (except one study with a LOAEL of ~0.1mg Al/kg bw). The collected data provide information regarding hazard identification and characterisation of pulmonary exposure to aluminium.

Hematologic evaluation of peripheral blood in Sprague Dawley rats by chronic exposure to aluminum chloride (AlCl3)

This study aimed to evaluate whether aluminum chloride (AlCl3) causes hematological changes in the peripheral blood of Sprague-Dawley (SD) rats. Five groups of female SD rats were intragastrically administered with 4 different concentrations of AlCl3 for 5 days a week for a total of 90 days. The aluminum concentration was determined via graphite furnace atomic absorption spectroscopy. Analysis of serum iron-kinetic profiles, blood cytometry outcomes, and blood smears of the blood samples. Scanning electron microscopy (SEM) and Raman spectroscopy were used to search for structural and ultrastructural changes, respectively. Blood aluminum concentration ranged 12.38-16.24 μg/L with no significant difference between experimental treatments. At the AlCl3 concentration of 40 mg Al/kg bw of rats/day, the mean ferritin value in the serum iron kinetic profile was 29.81±6.1 ng/mL, and this value showed a significant difference between experimental treatments. Blood cytometry revealed that there were 6.45-7.11×106 cells/μL erythrocytes, 8.91-9.32×103 cells/μL leukocytes, and 477.2-736.3×103 cells/μL platelets along with a hemoglobin of 37.38-41.93 g/dL and hematocrit level of 37.38-41.93%; the experimental treatments showed no significant differences. Erythrocyte structural analysis using SEM showed no differences between experimental treatments, whereas ultrastructural evaluation using Raman spectroscopy made it possible to identify the following bands: 741, 1123, 1350, 1578, and 1618 cm-1, which were respectively associated with the following vibrational modes and compounds: vibration of the tryptophan ring, asymmetric C-O-C stretching of glucose, C-H curve of tryptophan, C=C stretching of the heme group, and C-N stretching of the heme group, with no significant differences between experimental treatments. Therefore, AlCl3 administration does not induce ultrastructural changes in the erythrocyte membrane. This study revealed that serum ferritin concentration was the only parameter affected by AlCl3 exposure at 40 mg of Al/kg bw of rats/day.

Blood Aluminum Levels in Patients with Hemodialysis and Peritoneal Dialysis

Background. This retrospective observational study attempted to examine the prevalence of abnormal blood aluminum levels in dialysis patients, and to explore the association of pathogenic factors, such as demographic, clinical, laboratory as well as the use of phosphate binding drugs, drugs for secondary hyperparathyroidism and erythropoiesis-stimulating drugs with the blood aluminum levels. Methods. The study included 1175 patients (874 hemodialysis and 301 peritoneal dialysis), recruited from Chang Gung Memorial Hospital in November 2020. Patients were stratified into two groups by their blood aluminum levels, as normal (<2 µg/dL, n = 1150) or abnormal (≥2 µg/dL, n = 25). Results. The patients aged 60.4 ± 13.2 years and were dialyzed for 8.6 ± 8.1 years. The average blood aluminum level was 1.0 ± 0.4 µg/dL. Patients with abnormal blood aluminum levels received more sevelamer than patients with normal blood aluminum level (p = 0.014). Patients with abnormal blood aluminum levels had higher platelet count (p = 0.001), triglyceride (p < 0.001) and total iron binding capacity (p = 0.003) than patients with normal blood aluminum levels. Moreover, the cardiothoracic ratio was higher in patients with abnormal blood aluminum levels than patients with normal blood aluminum levels (p = 0.003). Conclusions. The prevalence of abnormal blood aluminum levels was low at 2.2%. Nevertheless, the linking of cardiothoracic ratio of more than 0.5 as well as elevated blood platelet count and triglyceride level with blood aluminum levels are interesting, and warranted more researches in this area.

Genotoxic Effects of Aluminum Chloride and Their Relationship with N-Nitroso-N-Methylurea (NMU)-Induced Breast Cancer in Sprague Dawley Rats

Recently, soluble forms of aluminum for human use or consumption have been determined to be potentially toxic due to their association with hepatic, neurological, hematological, neoplastic, and bone conditions. This study aims to assess the genotoxic effect of aluminum chloride on genomic instability associated with the onset of N-nitroso-N-methylurea (NMU)-induced breast cancer in Sprague Dawley rats. The dietary behavior of the rats was assessed, and the concentration of aluminum in the mammary glands was determined using atomic absorption spectroscopy. Genomic instability was determined in the histological sections of mammary glands stained with hematoxylin and eosin. Moreover, micronucleus in peripheral blood and comet assays were performed. The results of dietary behavior evaluation indicated no significant differences between the experimental treatments. However, aluminum concentration in breast tissues was high in the +2000Al/−NMU treatment. This experimental treatment caused moderate intraductal cell proliferation, lymph node hyperplasia, and serous gland adenoma. Furthermore, micronucleus and comet test results revealed that +2000Al/−NMU led to a genotoxic effect after a 10-day exposure and the damage was more evident after a 15-day exposure. Therefore, in conclusion, genomic instability is present and the experimental conditions assessed are not associated with breast cancer.

Aluminum hydroxide nebulization-induced redox imbalance and acute lung inflammation in mice

Purpose: Aluminum is the third most abundant metal in the earth's crust and is widely used in industry. Chronic contact with aluminum results in a reduction in the activity of electron transport chain complexes, leading to excessive production of reactive oxygen species (ROS) and oxidative stress. This study aimed to evaluate the effects of short-term exposure of aluminum hydroxide on oxidative stress and pulmonary inflammatory response.Materials and methods: Male BALB/c mice were divided into three groups: control group (CG); phosphate buffered saline group (PBSG) and aluminum hydroxide group (AHG). CG was exposed to ambient air, while PBSG and AHG were exposed to PBS or aluminum hydroxide solutions via nebulization, three times per day for five consecutive days. Twenty-four hours after the last exposure, all animals were euthanized for subsequent analysis.Results: Exposure to aluminum hydroxide in the blood resulted in lower platelet levels, higher neutrophils, and lower monocytes compared to CG and PBSG. Aluminum hydroxide promoted the recruitment of inflammatory cells to the lung. Macrophage, neutrophil and lymphocyte counts were higher in AHG compared to CG and PBSG. Protein oxidation and superoxide dismutase activity were higher, while catalase activity and reduced and oxidizes glutathione ratio in AHG were lower compared to CG and PBSG. Furthermore, there was an increase in the inflammatory markers CCL2 and IFN-γ in AHG compared to CG and PBSG.Conclusion: In conclusion, short-term nebulization with aluminum hydroxide induces the influx of inflammatory cells and oxidative stress in adult BALB/c mice.

Evaluated the adverse effects of cadmium and aluminum via drinking water to kidney disease patients: Application of a novel solid phase microextraction method

In present study aluminum (Al) and cadmium (Cd) were determined in ground water samples and assesses human health risks associated with elevated concentrations of toxic metals in dissolved form, using a novel solid phase microextraction (SPμE). Ground water sample (n=200) and biological sample (blood) of patients having chronic kidney disorders (CKD) along with healthy control subjects of same area (southern part of Pakistan) were collected. A simple system, including the micropipette tip packed with modified ionic liquid-activated carbon cloth (IL-ACC) coated with 8-hydroxyqunilone (8-HQ) attached to syringe. The analytes in water and acid digested blood samples were manually drawn for 2-10 cycles (drawing/discharging) at different pH range. The analytes sorbed on coated ACC were then desorbed with 2.0molL(-1) HNO3 in ethanol by drawing/discharging cycles for 1-5 times. The concentration of extracted analytes was determined by electrothermal atomic absorption spectrometer. The influence of different variables on the extraction efficiency of Cd and Al, were optimized. The Al and Cd concentrations in groundwater were found to be elevated than recommended limits by the World Health Organization. The urinary N-acetyl-h-glucosaminidase values were significantly higher in CKD patients as compared to refrent subjects (p<0.001). The significant variation in levels of Cd and Al were observed in blood samples of CKD patients than referents subjects (p<0.01). The strong positive correlation among Al and Cd levels in groundwater versus blood samples of CKD patients (r=0.82-0.85) p<0.01) was observed than those values calculated for referent subjects (r=0.425-0.536).

Correlation of cadmium and aluminum in blood samples of kidney disorder patients with drinking water and tobacco smoking: related health risk

The combined exposure to aluminum (Al) and cadmium (Cd) causes more pronounced adverse health effects on humans. The kidneys are the main organs affected by internal exposure to Cd and Al via food and non-food items. The objective of present study was to measure the Al and Cd concentrations in cigarettes tobacco (branded and non-branded) and drinking water (domestic treated, ground and lake water) samples in southern part of Pakistan, to assess the risk due to ingestion of water and inhalation of cigarettes smoke containing high concentrations of both elements. The study population (kidney disorder and healthy) divided into two group based on consuming lake and ground water, while smoking non-branded cigarette as exposed, while drinking domestic treated water and smoking branded cigarette as non-exposed. Electrothermal atomic absorption spectrometry was used to determined Cd and Al concentrations in tobacco, drinking water and blood samples. The resulted data indicated that the levels of Al and Cd in lake and underground water were higher than the permissible limit in drinking water recommended by the World Health Organization. The biochemical parameters of exposed and referent patients, especially urinary N-acetyl-h-glucosaminidase, were used as a biomarkers of kidney disorder. Exposed kidney disorder patients have higher levels of Cd and Al than the exposed referents subjects, while difference was significant when compared to resulted data of non-exposed patients and referents (p = 0.01-0.001). The pearson correlation showed positive correlation between both toxic element concentrations in water, cigarettes versus blood samples of exposed subjects (r = 0.20-0.67 and 0.71-0.82), while lower values were observed for non-exposed subjects (r = 0.123-0.423 and 0.331-0.425), respectively.

Comparative evaluation of essential and toxic elements in the blood of kidney failure patients and healthy referents

The aim of the present study was to evaluate the comparative distribution, correlation, and apportionment of selected elements-aluminum (Al), calcium (Ca), cadmium (Cd), potassium (K), magnesium (Mg), sodium (Na), and lead (Pb)-in the blood samples of male kidney failure patients (KFP) and healthy subjects of age ranged 30-60 years. The blood samples were digested with nitric acid and perchloric acid mixture (2:1), followed by the quantification of elements by atomic absorption spectrometry. The concentration of essential elements in blood samples of KFP were found in the range of Ca (97-125), Mg (18-36), Na (2971-3685), and K (177-270) mg/L while, the levels of Al, Cd, and Pb were found in the range of (475-1275), (0.9-9.9), and (211-623) μg/L, respectively. In the healthy referents, concentration of electrolytes in blood samples was lower than KFP, but difference was not significant (p > 0.05). While the levels of toxic elements in blood samples of referents were three- to sixfold lower than KFP (p < 0.01). Principal component analysis (PCA) and cluster analysis (CA) of the element data manifested diverse apportionment of the selected elements in the blood sample of the KFP compared with the healthy counterparts.

Electricity and colloidal stability: how charge distribution in the tissue can affects wound healing

The role of endogenous electric fields in wound healing is still not fully understood. Electric fields are of fundamental importance in various biological processes, ranging from embryonic development to disease progression, as described by many investigators in the last century. This hypothesis brings together some relevant literature on the importance of electric fields in physiology and pathology, the theory of biologically closed electric circuits, skin battery (a phenomenon that occurs after skin injury and seems to be involved in tissue repair), the relationship between electric charge and interstitial exclusion, and how skin tissues can be regarded as colloidal systems. The importance of electric charges, as established in the early works on the subject and the relevance of zeta potential and colloid stability are also analyzed, and together bring a new light for the physics involved in the wound repair of all the body tissues.

Separation/preconcentration methods for the determination of aluminum in dialysate solution and scalp hair samples of kidney failure patients

A new method is reported for the separation of aluminum ions (Al(3+)) from interfering cations in pharmaceutical and biological samples through solid-phase extraction (SPE) using 2-methyl-8-hydroxyquinoline (8-hydroxyquinaldine) on activated silica. While separated Al(3+) was preconcentrated by cloud point extraction (CPE) using 3,5,7,2'-4'-pentahydroxyflavone (morin) as complexing reagent, the resulting complex was entrapped in nonionic surfactant (Triton X-114) as prior step to its determination by spectrofluorimetry (SPF). The validity of separation/preconcentration of Al(3+) was checked by certified reference material of human hair and standard addition method. The chemical variables affecting the analytical performance of the separation/preconcentration methods were studied and optimized. The enrichment factor and detection limit of Al(3+) for the preconcentration of 10 ml of dialysate solution and acid-digested samples of scalp hair samples were found to be 25 and 0.34 μg/L, respectively. The relative standard deviation for six replicates of standard containing 20 μg/L of Al(3+) was <10%. In all DS, the concentration of Al was >10 μg/L. The level of Al in scalp hair samples of kidney failure patients was higher than healthy controls.

Alterations in trace elements and oxidative stress in uremic patients with dementia

The present study was conducted to compare the trace elements and oxidative status between uremic patients with and without dementia. Chronic hemodialysis patients with dementia (n = 20) and without dementia (n = 25), and age-matched healthy volunteers (n = 20) were enrolled. The nutritional status, blood levels of trace elements aluminum (Al), zinc (Zn), copper (Cu), magnesium (Mg) and iron (Fe), malondialdehyde (MDA), and protein carbonyl production, antioxidant enzymes glutathione peroxidase (GPx), and glutathione reductase (GR) activities were measured. No significant difference in nutritional status or clinical characteristics was observed between nondementia and dementia patients. However, uremic patients with dementia have significantly higher Al, Cu, and Mg and lower Zn concentrations, as well as increased Cu/Zn ratio in comparison to nondementia patients. There were statistically significant increased MDA and carbonyl production and decreased GPx and GR activities in dementia patients. Furthermore, the significant associations of Al, Mg, and Cu/Zn ratio with oxidative status in patients with dementia were noted. The dementia may initially worsen with abnormal metabolism of trace elements and oxidative stress occurrence. Our results suggest that abnormalities in trace element levels are associated with oxidative stress and may be a major risk factor in the dementia development of uremic patients.

Intradialytic and postdialytic platelet activation, increased platelet phosphatidylserine exposure and ultrastructural changes in platelets in children with chronic uremia

The present research evaluated the intradialytic and postdialytic changes in platelet factor-4 and beta-thromboglobulin plasma levels by enzyme-linked immunoadsorbent assay method and platelet aggregation by ADP as well as flow cytometric percentage of annexin-V-positive platelets as a measure of phosphatidylserine externalization and ultrastructural examination of platelets in 37 uremic patients on regular hemodialysis and 25 age-matched and sex-matched controls. Platelet factor-4 plasma levels increased, remain consistently high during hemodialysis session (20.24 +/- 3.05 IU/ml after 30 min, P < 0.001 and 23.67 +/- 3.68 IU/ml after 240 min, P < 0.001) and returned to control values (6.10 +/- 1.54 IU/ml) only after 24 h following the end of the session. beta-Thromboglobulin showed a trend similar to that of platelet factor-4. Platelet aggregation by ADP showed reduced function in comparison with controls (69.32 +/- 12.37 versus 91.95 +/- 1.59%, P < 0.001). Flow cytometric percentage of annexin-V-positive platelet was significantly elevated (P < 0.001) in uremic patients when compared with normal controls. Ultrastructural studies of platelets 30 min after starting of dialysis showed degranulation of its granules and at 240 min showed complete degranulation, whereas in the postdialytic phase (12 h after the end of dialysis) refilled alpha-granules started to appear. Positive correlations were found between platelet concentration and platelet factor-4 and beta-thromboglobulin plasma levels during and after dialysis (P < 0.001) and with annexin-V-positive platelets percentage (P < 0.001). In conclusion, activated platelets were found in chronic hemodialysis patients, a finding that may explain why uremic patients often suffer from thrombotic accidents. The platelet activation is associated with exposure of phosphatidylserine on the platelet exterior. Platelet factor-4 and beta-thromboglobulin are released from platelets as a result of a defect in their granules membrane as shown by the electron microscopy, mainly as a consequence of the blood-membrane contact during dialysis, and they return only slowly to control values.

Aluminum ions stimulate the oxidizability of low density lipoprotein by Fe2+: Implication in hemodialysis mediated atherogenic LDL modification

OBJECTIVE

Al(3+) stimulates Fe(2+) induced lipid oxidation in liposomal and cellular systems. Low-density lipoprotein (LDL) oxidation may render the particle atherogenic. As elevated levels of Al(3+) and increased lipid oxidation of LDL are found in sera of hemodialysis patients, we investigated the influence of Al(3+) on LDL oxidation.

MATERIALS AND METHODS

Using different LDL modifying systems (Fe(2+), Cu(2+), free radical generating compounds, human endothelial cells, hemin/H(2)O(2) and HOCl), the influence of Al(3+) on LDL lipid and apoprotein alteration was investigated by altered electrophoretic mobility, lipid hydroperoxide-, conjugated diene- and TBARS formation.

RESULTS

Al(3+) could stimulate the oxidizability of LDL by Fe(2+), but not in the other systems tested. Al(3+) and Fe(2+) were found to bind to LDL and Al(3+)could compete with Fe(2+) binding to the lipoprotein. Fluorescence polarization data indicated that Al(3+) does not affect the phospholipid compartment of LDL.

CONCLUSIONS

The results indicate that increased LDL oxidation by Fe(2+) in presence of Al(3+) might be due to blockage of Fe(2+) binding sites on LDL making more free Fe(2+) available for lipid oxidation.

Estimation of toxic metals in scalp hair samples of chronic kidney patients

The determination of toxic metals (TMs) in the biological samples of human beings is an important clinical screening procedure. The aim of this work is to determine total content of TMs, aluminum (Al), cadmium (Cd), nickel (Ni), and lead (Pb) in scalp hair samples of chronic kidney male patients (CKPs) on maintenance hemodialysis, during the period of 2005-2007. The study included 115 CKPs (all smokers) and 150 controls or referents [82 (nonsmokers) and 68 (smokers)]. Both controls and patients (males) were of the same age group (ranged 25-55 years), socioeconomic status, localities, and dietary habits. The scalp hair samples were analyzed by electrothermal atomic absorption spectrometer, prior to microwave-induced acid digestion. The accuracy of the total Al, Cd, Ni, and Pb measurements was tested by simultaneously analyzing certified reference material (human hair NCS ZC81002). No significant differences were observed between the analytical results and the certified values (paired t test at p > 0.05). The levels of TMs in scalp hair samples of patients were found to be higher as compared to control nonsmoker and smokers. Moreover, the study shows that levels of Al, Cd, Ni, and Pb in scalp hair samples may be useful to evaluate the impact of cigarette smoking in kidney failure patients.

Elevated levels of erythrocyte-conjugated dienes indicate increased lipid peroxidation in schistosomiasis mansoni patients

Schistosoma mansoni causes liver disease by inducing granulomatous inflammation. This favors formation of reactive oxygen species, including superoxide ions, hydrogen peroxide and hydroxyl radicals all of which may induce lipid peroxidation. We have evaluated lipid peroxidation in 18 patients with hepatosplenic schistosomiasis mansoni previously treated with oxamniquine followed by splenectomy, ligature of the left gastric vein and auto-implantation of spleen tissue, by measuring levels of erythrocyte-conjugated dienes and plasma malondialdehyde (MDA). Age-matched, healthy individuals (N = 18) formed the control group. Erythrocyte-conjugated dienes were extracted with dichloromethane/methanol and quantified by UV spectrophotometry, while plasma MDA was measured by reaction with thiobarbituric acid. Patient erythrocytes contained two times more conjugated dienes than control cells (584.5 +/- 67.8 vs 271.7 +/- 20.1 micromol/l, P < 0.001), whereas the increase in plasma MDA concentration (about 10%) was not statistically significant. These elevated conjugated dienes in patients infected by S. mansoni suggest increased lipid peroxidation in cell membranes, although this was not evident when a common marker of oxidative stress, plasma MDA, was measured. Nevertheless, these two markers of lipid peroxidation, circulating MDA and erythrocyte-conjugated dienes, correlated significantly in both patient (r = 0.62; P < 0.01) and control (r = 0.57; P < 0.05) groups. Our data show that patients with schistosomiasis have abnormal lipid peroxidation, with elevated erythrocyte-conjugated dienes implying dysfunctional cell membranes, and also imply that this may be attenuated by the redox capacity of antioxidant agents, which prevent accumulation of plasma MDA.