Blood pressure mediated the effects of cognitive function impairment related to aluminum exposure in Chinese aluminum smelting workers

Impact of multi-metal exposure on blood pressure: a mediation analysis through oxidative stress markers in China's Southern Jiangxi Province

Hypertension is a prevalent condition that contributes significantly to the global disease burden. Recent research endeavors have been investigating the potential causal link between metal exposure and the development of hypertension, yet consensus remains elusive. Nevertheless, studies examining the interplay among metal exposure, hypertension, and oxidative stress are relatively limited. This study utilized data from a cross-sectional survey conducted in southern Jiangxi Province, China. We evaluated urinary concentrations of 19 metals, including aluminum and manganese, in conjunction with measurements of systolic and diastolic blood pressures, as well as three oxidative stress biomarkers: glutathione peroxidase (GSH), superoxide dismutase (SOD), and malondialdehyde (MDA). In the monometallic model, chromium, iron, manganese, and molybdenum exhibited positive correlations with blood pressure. These findings were consistent in the mixed exposure model. Conversely, all the aforementioned metals exhibited a negative correlation with GSH and SOD, while demonstrating a positive correlation with MDA. Mediation effect analysis revealed that GSH and SOD mediated the relationships between urinary concentrations of aluminum, iron, manganese, and antimony and blood pressure. In contrast, MDA mediated the associations between urinary silver and antimony and blood pressure. Furthermore, GSH and SOD were identified as mediators in part of the relationship between mixed metal exposure and blood pressure, with mediation rates of 19.09% for GSH and 27.36% for SOD. The results of this study suggest that exposure to both individual and combined metals effects blood pressure levels, which are further associated with changes in oxidative stress levels. Moreover, oxidative stress levels may modulate the changes in blood pressure related to metal exposure, providing a basis for further investigation into the health risks associated with these metal exposures.

Path analysis of trace elements and physiological and biochemical indices associated to mild cognitive impairment in elderly Chinese

The intricate relationships between cognitive function and a broad spectrum of trace elements and physiological and biochemical indices remain unclear. This study aimed to employ a path analysis model to investigate the effects of multiple trace elements and physiological and biochemical factors on mild cognitive impairment (MCI) among elderly Chinese. A total of 5768 residents aged 60 years and older were recruited in Shenzhen, China. Cognitive function was evaluated using the Mini-Mental State Examination and the Mini-Cognitive Assessment. Concentrations of 18 trace elements in urine were quantified with adjustments for urinary creatinine levels. Physiological and biochemical indices were acquired at community health centers. Based on the multiple logistic regression analysis, only selenium exhibited significant negative correlations with MCI (p-trend = 0.035). Serum albumin (ALB), triglyceride (TG), bone mineral density (BMD) and mitochondrial DNA copy number (mtDNAcn) exhibited negative correlations with high risk of MCI, whereas serum uric acid (SUA) and fasting blood glucose (FBG) were positively correlated with a higher risk of MCI. In addition, the path analysis model demonstrated that cobalt had direct effect on cognitive function, whereas iron, manganese, selenium, zinc, and copper affected it indirectly. Furthermore, the model identified that mtDNAcn directly affected cognitive function, while the other four physiological and biochemical indicators, including ALB, TG, BMD and SUA, had both direct and interactive indirect effects on it. Trace elements and physiological and biochemical indices exerted both direct and indirect effects on MCI. Specifically, trace elements might indirectly affect cognitive function through physiological and biochemical indices, which interact with each other.

The effects of occupational aluminum exposure on blood pressure and blood glucose in workers - A longitudinal study in northern China

BACKGROUND

Trace element and metal exposure is closely related to the occurrence of chronic diseases, particularly affecting blood pressure and blood glucose. Current studies suggest that heavy metal exposure is a risk factor for hypertension and diabetes. Aluminum can enter the human body through daily life and occupational exposure from food, environment, drugs, and other sources, affecting the cardiovascular, endocrine, and other systems. Therefore, it is significant to observe the effect of aluminum on blood pressure and blood glucose in workers with high concentration.

OBJECTIVE

In this study, electrolytic workers naturally exposed to high concentrations of aluminum were selected. The aim of the 5-year cohort study was to investigate the effects of continuous occupational aluminum exposure on blood pressure and blood glucose in workers and to assess the risk of potential cardiovascular and metabolic diseases due to heavy metal exposure.

METHODS

In 2014, 183 participants from an electrolysis workshop at an aluminum plant in Shanxi were enrolled. Inductively coupled plasma mass spectrometry (ICP-MS) was performed to determine the plasma aluminum (P-Al) concentration of the workers and measured their blood pressure and glucose levels. At the 2019 follow-up, all parameters were measured again in the same workers. The relationship of the P-Al concentration with blood pressure and glucose levels was assessed using generalized linear regression, and risks of developing hypertension and hyperglycemia (diabetes or pre-diabetes) due to Al exposure were assessed using binary logistic regression. Dose-response relationships between average annual rates of change in P-Al and average annual rates of change in blood pressure and blood glucose were analyzed using RCS. The relative risk (RR) and attributable risk (AR) were also calculated.

RESULTS

Generalized linear regression showed that the average annual rate of change in P-Al concentration was positively correlated with the annual rates of change in SBP, DBP, and blood glucose levels, with each e-fold increase in P-Al concentration increasing the annual rates of change in SBP and DBP by 3.55 % (P < 0.01) and 3.43 % (P = 0.03), respectively. Binary logistic regression showed that as the average annual rate of change in P-Al concentration (categorical variable) increased, the risk of developing hypertension increased (Ptrend < 0.05). The RCS results showed that the relationship between the average annual rate of change in P-Al and the average annual rate of change in SBP was a showed a dose-response relationship (P for overall association<0.05). RR and AR increased with increasing P-Al concentration in both hypertensive and diabetic patients.

CONCLUSION

Persistent occupational aluminum exposure is associated with elevated blood pressure levels in workers and increases the risk of developing hypertensive disorders.

Impact of the environmental pollution on cardiovascular diseases: From epidemiological to molecular evidence

Environmental pollution poses a significant threat to human health, particularly concerning its impact on cardiovascular diseases (CVDs). This review synthesizes epidemiological and molecular evidence to elucidate the intricate relationship between environmental pollutants and CVDs. Epidemiological studies highlight the association between exposure to air, water, and soil pollutants and increased CVD risk, including hypertension, coronary artery disease, and stroke. Furthermore, molecular investigations unravel the underlying mechanisms linking pollutant exposure to CVD pathogenesis, such as oxidative stress, inflammation, endothelial dysfunction, and autonomic imbalance. Understanding these molecular pathways is crucial for developing targeted interventions and policy strategies to mitigate the adverse effects of environmental pollution on cardiovascular health. By integrating epidemiological and molecular evidence, this review provides insights into the complex interplay between environmental factors and CVDs, emphasizing the urgent need for comprehensive preventive measures and environmental policies to safeguard public health.

Preparation of Edible Colorant Lake Using Calcium Carbonate and β-Carotene: Structural Characterization and Formation Mechanism Study

This study prepared a novel β-carotene colorant lake using calcium carbonate (CaCO3) and investigated the lake formation process and its basic characteristics. Kinetic adsorption analysis confirmed that medium pH (9.3) and medium temperature (40 °C) were more suitable for lake preparation, while desorption occurred, possibly due to crystalline transformation of CaCO3. The isothermal analysis and model fitting results suggested that the β-carotene and CaCO3 particles combined via a monolayer adsorption process driven by physical force. Electrostatic attraction likely participated in the process due to the net negative surface charges of β-carotene dispersion and positively charged groups on the CaCO3 particle surfaces. Ethanol, ultrasonic treatment, and drying method significantly influenced the immobilization efficiency (IE) of β-carotene in the lake and light stability of the lake, without affecting its crystal form. The thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) curves confirmed absorption of β-carotene onto CaCO3. Fourier-transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) analyses indicated no obvious chemical bonds between β-carotene and CaCO3. Energy-dispersive spectroscopy (EDS) confirmed the presence of β-carotene on surfaces but not in the interior of the CaCO3 particles. The adsorption of β-carotene by calcium carbonate was further confirmed to be a physical adsorption on surface.

A review of the epidemiological and laboratory evidence of the role of aluminum exposure in pathogenesis of cardiovascular diseases

The objective of the present study was to review the epidemiological and laboratory evidence on the role of aluminum (Al) exposure in the pathogenesis of cardiovascular diseases. Epidemiological data demonstrated an increased incidence of cardiovascular diseases (CVD), including hypertension and atherosclerosis in occupationally exposed subjects and hemodialysis patients. In addition, Al body burden was found to be elevated in patients with coronary heart disease, hypertension, and dyslipidemia. Laboratory studies demonstrated that Al exposure induced significant ultrastructural damage in the heart, resulting in electrocardiogram alterations in association with cardiomyocyte necrosis and apoptosis, inflammation, oxidative stress, inflammation, and mitochondrial dysfunction. In agreement with the epidemiological findings, laboratory data demonstrated dyslipidemia upon Al exposure, resulting from impaired hepatic lipid catabolism, as well as promotion of low-density lipoprotein oxidation. Al was also shown to inhibit paraoxonase 1 activity and to induce endothelial dysfunction and adhesion molecule expression, further promoting atherogenesis. The role of Al in hypertension was shown to be mediated by up-regulation of NADPH-oxidase, inhibition of nitric oxide bioavailability, and stimulation of renin-angiotensin-aldosterone system. It has been also demonstrated that Al exposure targets cerebral vasculature, which may be considered a link between Al exposure and cerebrovascular diseases. Findings from other tissues lend support that ferroptosis, pyroptosis, endoplasmic reticulum stress, and modulation of gut microbiome and metabolome are involved in the development of CVD upon Al exposure. A better understanding of the role of the cardiovascular system as a target for Al toxicity will be useful for risk assessment and the development of treatment and prevention strategies.

The role of Nrf2/HO-1 signal pathway in regulating aluminum-induced apoptosis of PC12 cells

BACKGROUND

Aluminum has definite neurotoxicity and can lead to apoptosis of nerve cells, but the specific mechanism remains to be further explored. The aim of this study was to investigate the role of Nrf2/HO-1 signaling pathway in neural cell apoptosis induced by aluminum exposure.

METHODS

In this study, PC12 cells were used as the research object, aluminum maltol [Al(mal)₃] was used as the exposure agent, and tert-butyl hydroquinone (TBHQ), an agonist of Nrf2, was used as the intervention agent to construct an in vitro cell model. Cell viability was detected by CCK-8 method, cell morphology was observed by light microscope, cell apoptosis was measured by flow cytometry, and expression of Bax and Bcl-2 proteins and Nrf2/HO-1 signaling pathway proteins were investigated by western blotting.

RESULTS

With the increase of Al(mal)₃ concentration, PC12 cell viability decreased, the early apoptosis rate and total apoptosis rate increased, the ratio of Bcl-2 and Bax protein expression decreased, and Nrf2/HO-1 pathway protein expression decreased. The use of TBHQ could activate the Nrf2/HO-1 pathway and reverse the apoptosis of PC12 cells induced by aluminum exposure.

CONCLUSION

Nrf2/HO-1 signaling pathway plays a neuroprotective role in the apoptosis of PC12 cells caused by Al(mal)₃, which provides a possible target for the intervention of aluminum induced neurotoxicity.

Clinical Outcomes of the Deleterious Effects of Aluminum on Neuro-Cognition, Inflammation, and Health: A Review

Introduction: In the scenario of metal toxicity, aluminum (Al) stands out as a ubiquitous type of metal that can be combined with other elements and form different compounds. Al is widely used daily as an adjuvant in vaccines, antacids, food additives (as components of AI-containing food additives), skin care products, cosmetics, and kitchenware, and can be an element or contaminant present in our daily life. Objective: To present a review of the main deleterious effects of Al on human health. Methods: The search was carried out from September 2022 to February 2023 in the Scopus, PubMed, Science Direct, Scielo, and Google Scholar databases, using scientific articles from 2012 to 2023. The quality of the studies was based on the GRADE instrument, and the risk of bias was analyzed according to the Cochrane instrument. Results and Conclusions: A total of 115 files were search returned. Further, 95 articles were evaluated, and 44 were included in this review. Based on the results, measuring Al's relevance to health is essential in medicine. Several studies have demonstrated clinical outcomes and metabolic alterations with Al exposure. The tolerable weekly intake established by the European Food Safety Authority (EFSA) of 1 mg Al/kg body weight can be achieved through dietary exposure alone. Proven neurotoxicity in humans is the critical adverse effect of Al. A carcinogenic effect of Al has not been proven so far. Preventive medicine advocates that exposure to Al should be kept as low as possible. Chelating agents, such as calcium disodium ethylene diamine tetraacetic acid and deferoxamine, are options for acute poisoning, and monomethysilanetriol supplementation may be a long-term strategy with chelation potential. Further studies are needed to assess the impacts of Al on human health.