Depletion of serum zinc in ischemic stroke patients

From zinc homeostasis to disease progression: Unveiling the neurodegenerative puzzle

Zinc is a crucial trace element in the human body, playing a role in various physiological processes such as oxidative stress, neurotransmission, protein synthesis, and DNA repair. The zinc transporters (ZnTs) family members are responsible for exporting intracellular zinc, while Zrt- and Irt-like proteins (ZIPs) are involved in importing extracellular zinc. These processes are essential for maintaining cellular zinc homeostasis. Imbalances in zinc metabolism have been linked to the development of neurodegenerative diseases. Disruptions in zinc levels can impact the survival and activity of neurons, thereby contributing to the progression of neurodegenerative diseases through mechanisms like cell apoptosis regulation, protein phase separation, ferroptosis, oxidative stress, and neuroinflammation. Therefore, conducting a systematic review of the regulatory network of zinc and investigating the relationship between zinc dysmetabolism and neurodegenerative diseases can enhance our understanding of the pathogenesis of these diseases. Additionally, it may offer new insights and approaches for the treatment of neurodegenerative diseases.

Stroke-induced damage on the blood-brain barrier

The blood-brain barrier (BBB) is a functional phenotype exhibited by the neurovascular unit (NVU). It is maintained and regulated by the interaction between cellular and non-cellular matrix components of the NVU. The BBB plays a vital role in maintaining the dynamic stability of the intracerebral microenvironment as a barrier layer at the critical interface between the blood and neural tissues. The large contact area (approximately 20 m2/1.3 kg brain) and short diffusion distance between neurons and capillaries allow endothelial cells to dominate the regulatory role. The NVU is a structural component of the BBB. Individual cells and components of the NVU work together to maintain BBB stability. One of the hallmarks of acute ischemic stroke is the disruption of the BBB, including impaired function of the tight junction and other molecules, as well as increased BBB permeability, leading to brain edema and a range of clinical symptoms. This review summarizes the cellular composition of the BBB and describes the protein composition of the barrier functional junction complex and the mechanisms regulating acute ischemic stroke-induced BBB disruption.

Total oxidant/antioxidant status, copper and zinc levels in acute ischemic stroke patients after mechanical thrombectomy

BACKGROUND AND PURPOSE

We aimed to identify the relationship of total antioxidant status, total oxidant status, and copper (Cu) and zinc (Zn) situations with the short-term prognostic and stroke severity in acute ischemic stroke cases who were successfully recanalized by mechanical thrombectomy.

METHODS

A study of 36 acute ischemic stroke patients and 22 controls were prospectively studied. Tube samples were attained at admission and 24 h after recanalization. In patients who were successfully recanalized (thrombolysis in cerebral infarction ≥ 2b), a 3-month modified Rankin scale (mRS) score of 0-2 was considered a good prognosis, and a score of 3-6 was considered a poor prognosis.

RESULTS

Admission Cu levels were significantly higher in the poor prognosis group (p = 0.031). In the multivariate logistic regression analysis, Cu was not associated with poor prognosis (p = 0.357). Cu and Zn levels were lower in the patients group compared to controls (p = 0.014 and p = 0.010, respectively). There was no correlation between National Institute of Health Stroke Scale and biomarkers (p > 0.05). The temporal variation of biomarkers did not differ significantly between the good prognosis and poor prognosis groups (p interaction > 0.05).

CONCLUSIONS

High admission Cu levels were associated with poor prognosis, but this association was limited. In addition, Cu and Zn levels were statistically lower in patients. There was no relationship between total antioxidant/oxidant status and short-term prognosis or stroke severity.

The Important Role of Zinc in Neurological Diseases

Zinc is one of the most abundant metal ions in the central nervous system (CNS), where it plays a crucial role in both physiological and pathological brain functions. Zinc promotes antioxidant effects, neurogenesis, and immune system responses. From neonatal brain development to the preservation and control of adult brain function, zinc is a vital homeostatic component of the CNS. Molecularly, zinc regulates gene expression with transcription factors and activates dozens of enzymes involved in neuronal metabolism. During development and in adulthood, zinc acts as a regulator of synaptic activity and neuronal plasticity at the cellular level. There are several neurological diseases that may be affected by changes in zinc status, and these include stroke, neurodegenerative diseases, traumatic brain injuries, and depression. Accordingly, zinc deficiency may result in declines in cognition and learning and an increase in oxidative stress, while zinc accumulation may lead to neurotoxicity and neuronal cell death. In this review, we explore the mechanisms of brain zinc balance, the role of zinc in neurological diseases, and strategies affecting zinc for the prevention and treatment of these diseases.

Dietary metal intake and the prevalence of erectile dysfunction in US men: Results from National Health and Nutrition Examination Survey 2001-2004

BACKGROUND

Erectile dysfunction (ED) mainly affects men over 40 years of age and is a common clinical condition. In addition to hypertension and diabetes, environment, and lifestyle are also significantly associated with erectile dysfunction. The relationship between dietary trace metal intake and ED has not been studied.

MATERIALS AND METHODS

Data on participants were obtained from the National Health and Nutrition Examination Survey for this study, and those with incomplete information on clinical variables were excluded. Dose-response curve analysis was used to investigate the relationship between dietary trace metal intake and ED prevalence. Multivariate logistic regression analysis was used to adjust for confounders to further investigate the relationship between dietary trace metal intake and ED prevalence. 1:1 propensity score matching (PSM) was performed to adjust for differences between clinical variables for data reanalysis to confirm the reliability of the results.

RESULTS

A total of 3,745 individuals were included in the study, including 1096 ED patients and 2,649 participants without ED. Dietary intake of trace metals (Mg, Zn, Cu, and Se) was significantly higher in participants without ED than in ED patients (all P < 0.001). Dose-response curve analysis showed a significant negative association between these dietary metal intakes and ED prevalence (all P < 0.001). Multivariate logistic regression analysis adjusted for confounders (age, education, BMI, annual household income, hypertension, diabetes, marital status, race, and current health status) revealed that increased dietary metal intake reduced the odds ratio of ED. 1:1 PSM reanalysis further confirmed the validity of the results.

CONCLUSION

Increasing dietary intake of trace metals (magnesium, zinc, copper, and selenium) within the upper limit is beneficial in reducing the prevalence of ED.

Comparison of zinc levels in the various biosubstrates of patients with unstable atherosclerotic plaque

The article describes the content and comparative characteristics of zinc level in the hair, biopsies of carotid atherosclerotic plaques (AP) and serum in patients with carotid atherosclerosis. The highest concentration of zinc is found in hair compared to the AP and serum. Zinc levels is higher in AP than in the serum. It is noteworthy that the level of zinc in biopsies of unstable AP was lower compared to the level of zinc in hair.

Serum/Plasma Zinc Is Apparently Increased in Ischemic Stroke: a Meta-analysis

Zinc (Zn) is found in many neuronal pathways in the brain and has implications for neuromodulation and cerebrovascular disease. However, the association between Zn levels and stroke risk remains controversial. Therefore, we conducted a meta-analysis to explore these relationships. A systematic literature search using PubMed, EMBASE database, and Google Scholar was performed for relevant articles from inception to August 2020. Standardized mean differences (SMDs) and 95% confidence intervals (CIs) were considered the effect sizes and statistical analyses were performed using Stata 12.0. A total of 12 studies involving 1878 cases of stroke and 1754 controls were enrolled. Overall, the meta-analysis demonstrated no significant difference in Zn levels between the stroke group and control group (SMD =-0.18, 95% CI =-0.69 to 0.32, P = 0.480). Subgroup analysis showed that type of stroke had an influence on the Zn levels. A meta-analysis of nine ischemic stroke (IS) studies, which included 1645 cases and 1585 controls, revealed that the Zn levels were significantly higher in IS patients than in controls (SMD (95% CI): 0.61(0.04, 1.19), P = 0.036), but no significant association was found between Zn levels and risk of hemorrhagic stroke (P = 0.113). Egger's test indicated no significant publication bias. This meta-analysis indicates that higher Zn levels may be associated with increased risk of IS; however, these findings should be further confirmed.

Zinc deficiency as a possible risk factor for increased susceptibility and severe progression of Corona Virus Disease 19

The importance of Zn for human health becomes obvious during Zn deficiency. Even mild insufficiencies of Zn cause alterations in haematopoiesis and immune functions, resulting in a proinflammatory phenotype and a disturbed redox metabolism. Although immune system malfunction has the most obvious effect, the functions of several tissue cell types are disturbed if Zn supply is limiting. Adhesion molecules and tight junction proteins decrease, while cell death increases, generating barrier dysfunction and possibly organ failure. Taken together, Zn deficiency both weakens the resistance of the human body towards pathogens and at the same time increases the danger of an overactive immune response that may cause tissue damage. The case numbers of Corona Virus Disease 19 (COVID-19) are still increasing, which is causing enormous problems for health systems and economies. There is an urgent need to reduce both the number of severe cases and the resulting deaths. While therapeutic options are still under investigation, and first vaccines have been approved, cost-effective ways to reduce the likelihood of or even prevent infection, and the transition from mild symptoms to more serious detrimental disease, are highly desirable. Nutritional supplementation might be an effective option to achieve these aims. In this review, we discuss known Zn deficiency effects in the context of an infection with Severe Acute Respiratory Syndrome-Coronavirus-2 and its currently known pathogenic mechanisms and elaborate on how severe pre-existing Zn deficiency may pre-dispose patients to a severe progression of COVID-19. First published clinical data on the association of Zn homoeostasis with COVID-19 and registered studies in progress are listed.

Current status and outlook of biodegradable metals in neuroscience and their potential applications as cerebral vascular stent materials

Over the past two decades, biodegradable metals (BMs) have emerged as promising materials to fabricate temporary biomedical devices, with the purpose of avoiding potential side effects of permanent implants. In this review, we first surveyed the current status of BMs in neuroscience, and briefly summarized the representative stents for treating vascular stenosis. Then, inspired by the convincing clinical evidence on the in vivo safety of Mg alloys as cardiovascular stents, we analyzed the possibility of producing biodegradable cerebrovascular Mg alloy stents for treating ischemic stroke. For these novel applications, some key factors should also be considered in designing BM brain stents, including the anatomic features of the cerebral vasculature, hemodynamic influences, neuro-cytocompatibility and selection of alloying elements. This work may provide insights into the future design and fabrication of BM neurological devices, especially for brain stents.

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The current status of the application of biodegradable metals (BM) in neuroscience was presented.

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We analyzed the possibility of producing biodegradable cerebrovascular Mg alloy stents for ischemic stroke treatment.

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Key factors in designing BM brain stents were discussed.

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This work may provide insights into the future design and fabrication of BM neurological devices, especially for brain stents.

Serum Zinc Levels and Incidence of Ischemic Stroke: The Reasons for Geographic and Racial Differences in Stroke Study

BACKGROUND AND PURPOSE

Despite zinc's role as an antioxidant and anti-inflammatory agent, prospective studies relating zinc levels to ischemic stroke risk are lacking. To examine the association between serum zinc levels and incidence of ischemic stroke in a US population.

METHODS

Using a case-cohort study nested within the Reasons for Geographic and Racial Differences in Stroke cohort, participants were randomly selected from the Reasons for Geographic and Racial Differences in Stroke cohort to generate a sub-cohort (n=2346). All incident ischemic stroke cases as of September 2012 (n=660) were included, with 62 incident cases overlapping in the sub-cohort. Serum zinc levels were measured at baseline. Barlow-weighted Cox's proportional hazards regression models were used to calculate multivariable-adjusted hazard ratios and the corresponding 95% CI of ischemic stroke by serum zinc levels.

RESULTS

The median zinc level for the sub-cohort was 121.19 µg/dL (interquartile range, 104.86-140.39 µg/dL). Serum zinc levels were inversely associated with incidence of ischemic stroke after adjustment for potential confounders (quartile 4 versus quartile 1: hazard ratio, 0.78 [95% CI, 0.61-0.98], P=0.03 for trend). When stratified by prespecified factors (sex, race, region), only sex showed a significant modification (P=0.03 for interaction). The inverse association was more pronounced among females (quartile 4 versus quartile 1: hazard ratio, 0.58 [95% CI, 0.41-0.84], P<0.01 for trend) than males (quartile 4 versus quartile 1: hazard ratio, 1.08 [95% CI, 0.78-1.51], P=0.92 for trend).

CONCLUSIONS

Serum zinc concentration was inversely associated with incidence of ischemic stroke, especially among women, indicating that low zinc levels may be a risk factor for ischemic stroke.

Zinc as a Biomarker of Cardiovascular Health

The importance of zinc (Zn) for cardiovascular health continuously gains recognition. As shown earlier, compromised Zn homeostasis and prolonged inflammation are common features in various cardiovascular diseases (CVDs). Similarly, Zn biochemistry alters several vascular processes, and Zn status is an important feature of cardiovascular health. Zn deficiency contributes to the development of CVDs; thus, Zn manipulations, including Zn supplementation, are beneficial for preventing and treating numerous cardiovascular (CV) disorders. Finally, additional long-term, well-designed studies, performed in various population groups, should be pursued to further clarify significant relationships between Zn and CVDs.

Selenium, Copper, Zinc Concentrations and Cu/Zn, Cu/Se Molar Ratios in the Serum of Patients with Acute Ischemic Stroke in Northeastern Poland-A New Insight into Stroke Pathophysiology

Background: In recent years, trace elements (TEs) have gained considerable attention in the course of treatment and diagnosis of ischemic stroke. The purpose of the conducted research was to determine the trace mineral status (Se, Cu, Zn, Cu/Zn ratio, and Cu/Se ratio) in patients with acute ischemic stroke compared to the population of healthy people in the northeastern region of Poland. Materials and methods: 141 patients with acute ischemic stroke (AIS) and 69 healthy control subjects were examined. The serum concentrations of mineral components were assessed by the atomic absorption spectrometry method. Clinical parameters were updated based on medical records. Results: The serum Se and Zn concentrations were significantly decreased (p < 0.0001; p < 0.0001) in patients with AIS compared with healthy control subjects. However, no significant differences were revealed in terms of the serum Cu concentration (p = 0.283). As expected, we found that the serum Cu/Zn and Cu/Se molar ratios were significantly higher (p = 0.001; p < 0.0001) in patients with AIS compared with healthy control subjects. Conclusions: Disturbed metal homeostasis is a significant contributor to AIS pathogenesis. Furthermore, marked disruption of the serum Cu/Zn and Cu/Se molar ratios could serve as a valuable indicator of AIS patients’ nutritional status and oxidative stress levels.

Zinc Deficiency-An Independent Risk Factor in the Pathogenesis of Haemorrhagic Stroke?

Zinc is an essential trace element for human health and plays a fundamental role in metabolic, immunological and many other biological processes. The effects of zinc are based on the intra- and extracellular regulatory function of the zinc ion (Zn2+) and its interactions with proteins. The regulation of cellular zinc homeostasis takes place via a complex network of metal transporters and buffering systems that react to changes in the availability of zinc in nutrition, chronic diseases, infections and many other processes. Zinc deficiency is associated with impairment of numerous metabolic processes, reduced resistance to infections due to impaired immune functions, changes in skin and its appendages and disorders of wound healing and haemostasis. While ischemic heart attacks (myocardial infarction) occur more frequently with meat-based normal diets, haemorrhagic strokes are more frequently observed with vegetarian/vegan diets. The causes are discussed as deficiencies of various micronutrients, such as vitamin B12, vitamin D, various amino acids and also zinc. In the present review, after a description of the functions of zinc and its resorption, a discussion of daily food intake will follow, with a special focus on the importance of food composition and preparation for the zinc balance. The close interrelationships between proteins, especially albumin and zinc will be discussed. Finally, the possible causes and consequences of a zinc deficiency on the blood vessels and blood coagulation are considered.

Association Between the Change of Serum Copper and Ischemic Stroke: a Systematic Review and Meta-Analysis

Ischemic stroke is the most common stroke subtypes with all strokes. More and more studies found that serum copper was related to the ischemic stroke. However, the correlation between serum copper and ischemic stroke was inconsistent. We performed the meta-analysis to assess the association between the change of serum copper and ischemic stroke. Electronic databases were identified to search for relevant studies about serum copper and ischemic stroke from inception to February 28, 2019. Eight studies with a total of 777 participants were included into this meta-analysis. Because of high heterogeneity (I² = 71%), we chose a random effect model. Our results showed the serum copper levels were significantly higher in ischemic stroke group compared with controls group (pooled mean difference, 1.25; 95% confidence intervals (CIs), 0.07-2.43; P = 0.04), in particular studies after the year of 2009 (I² = 0%; pooled mean difference, 2.16; 95% CI, 1.37-2.95; P < 0.00001). Serum copper was associated with ischemic stroke, and it may be one of the risk factors of ischemic stroke.

The interaction of zinc and the blood-brain barrier under physiological and ischemic conditions

Zinc is the second most abundant metal in human and serves as an essential trace element in the body. During the past decades, zinc has been found to play important roles in central nervous system, such as the development of neurons and synaptic activities. An imbalance of zinc is associated with brain diseases. The blood-brain barrier (BBB) maintains the homeostasis of the microenvironment, regulating the balance of zinc in the brain. A compromised BBB is the main cause of severe complications in cerebral ischemic patients, such as hemorrhage transformation, inflammation and edema. Recent studies reported that zinc in the brain may be a potential target for integrative protection against ischemic brain injury. Although zinc has long been regarded as important transmitters in central nervous system, the critical role of zinc dyshomeostasis in damage to the BBB has not been fully recognized. In this review, we summarize the role of the BBB in regulating homeostasis of zinc in physiological conditions and the effects of changes in zinc levels on the permeability of the BBB in cerebral ischemia. The integrity of BBB maintains the homeostasis of zinc in pathological conditions, while the balance of zinc in the brain and the circulation maintains the normal function of the BBB. Interrupting the zinc/BBB system will disturb the microenvironment in the brain, leading to pathological diseases. In stroke patients, zinc may serve as a potential target for protecting the BBB and reducing hemorrhage transformation, inflammation and edema.

Increased Zinc Serum Level: New Clues in Babol Stroke Patients, Northern Iran

Background

Stroke is the second leading cause of death worldwide. The role of zinc as a new predictor of stroke was considered.

Methods

This prospective study was conducted in Ayatollah Rouhani Hospital within a year on 100 stroke and 100 control patients.

Findings

The difference in zinc serum level in two groups was significant (deficiency: 3 (3%) in patients versus 20 (20%) in control group, normal: 25 (25%) versus 54 (54%), and increased level: 72 (72%) versus 26 (26%); p < 0.001). Difference in zinc serum levels was statistically significant with ischemic heart disease (deficiency: 0 cases (0%), normal: 8 cases (24%), increased level: 24 cases (75%), p = 0.003). Increases in zinc serum level were significantly correlated with the frequency of hemorrhagic and ischemic patients (deficiency: 3 (3.3%) hemorrhagic versus 0 (0%) ischemic; normal: 19 (21%) versus 6 (60%), increased level: 68 (75.6%) versus 4 (40%); p = 0.025). Regression logistics showed that ischemic heart disease (p < 0.001; OR = 28.29, %95 CI: 5.53; 144.87), hyperlipidemia (p < 0.001; OR = 0.26, %95 CI: 0.12; 0.56), and zinc serum level (p < 0.001, OR = 15.53, %95 CI: 4.03; 59.83) each had a significant role.

Conclusions

Babol stroke patients are prone to increased zinc serum level as a new parameter. Ischemic heart disease, increased levels of zinc, and hyperlipidemia were found to be probable predictor factors for stroke in Babol.

Prospective Study of Dietary Zinc Intake and Risk of Cardiovascular Disease in Women

Several animal and human studies have shown that zinc is associated with cellular damage and cardiac dysfunction. This study aims to investigate dietary zinc and the zinc-iron ratio, as predictors of incident cardiovascular disease (CVD) in a large longitudinal study of mid-age Australian women (aged 50-61 years). Data was self-reported and validated food frequency questionnaires were used to assess dietary intake. Energy-adjusted zinc was ranked using quintiles and predictors of incident CVD were examined using stepwise logistic regression. After six years of follow-up, 320 incident CVD cases were established. A positive association between dietary zinc intake, zinc-iron ratio and risk of CVD was observed even after adjusting for potential dietary and non-dietary confounders. Compared to those with the lowest quintile of zinc, those in the highest quintile (Odds Ratio (OR) = 1.67, 95% Confidence Interval (CI) = 1.08-2.62) and zinc-iron ratio (OR = 1.72, 95% CI = 1.05-2.81) had almost twice the odds of developing CVD (p trend = 0.007). This study shows that high dietary zinc intake and zinc-iron ratio is associated with a greater incidence of CVD in women. Further studies are required detailing the source of zinc and iron in diet and their precise roles when compared to other essential nutrients.

Trace minerals intake: Risks and benefits for cardiovascular health

Minerals play a major role in regulating cardiovascular function. Imbalances in electrolyte minerals are frequent and potentially hazardous occurrences that may lead to the development of cardiovascular diseases (CVDs). Transition metals, such as iron, zinc, copper and selenium, play a major role in cell metabolism. However, there is controversy over the effects of dietary and supplemental intake of these metals on cardiovascular risk factors and events. Since their pro-oxidant or antioxidant functions can have different effects on cardiovascular health. While deficiency of these trace elements can cause cardiovascular dysfunction, several studies have also shown a positive association between metal serum levels and cardiovascular risk factors and events. Thus, a J- or U-shaped relationship between the transition minerals and cardiovascular events has been proposed. Given the existing controversies, large, well-designed, long-term, randomized clinical trials are required to better examine the effects of trace mineral intake on cardiovascular events and all-cause mortality in the general population. In this review, we discuss the role of dietary and/or supplemental iron, copper, zinc, and selenium on cardiovascular health. We will also clarify their clinical applications, benefits, and harms in CVDs prevention.

Serum trace elements are interrelated with hormonal imbalance in men with acute ischemic stroke

The objective of the present study was to assess hormonal and trace element status in men suffering from acute ischemic stroke.

METHODS

21 acute ischemic stroke patients and 21 age- and body mass index-matched healthy volunteers were enrolled in the study. Serum trace elements were assessed using inductively coupled plasma mass spectrometry. Serum hormones and brain damage markers were estimated using enzyme-linked immunosorbent assay.

RESULTS

Ischemic stroke patients are characterized by significantly higher levels of total and free triiodothyronine (T₃), anti-thyroid peroxidase antibodies (Anti-TPO-Ab), prolactin, and cortisol, whereas the level of thyroid stimulating hormone (TSH) was decreased. Serum B, Cu, Li, Mn, Ni, Pb, Se, V, and Zn in stroke significantly exceeded the control values, whereas the level of Co and Fe was decreased. Correlation analysis revealed a significant association between serum B and T₃, Anti-TPO-Ab, and iodine concentration; serum Li and Sr levels - with circulating TSH, free T3, and Anti-TPO-Ab; and V concentration - with total T₃ and I levels. The following positive relationships were also revealed: Co - TSH, Mn - free T₃, Zn - free T₃. Multiple linear regression demonstrated that Co, I, and Li were directly related to circulating TSH levels, whereas V concentration was negatively interrelated. In turn, only serum Li levels were characterized by a significant direct relationship with free T3 values.

CONCLUSION

Generally, the obtained data demonstrate that altered serum trace elements are associated with thyroid dysfunction in acute ischemic stroke patients. However, the causal relationship should be estimated.

Serum trace elements are associated with hemostasis, lipid spectrum and inflammatory markers in men suffering from acute ischemic stroke

The primary objective of the study is investigation of the association between trace elements status and hemostasis, lipid spectrum and inflammatory markers in acute ischemic stroke (AIS). A total of 30 men suffering from AIS and 30 healthy controls were involved in the current survey. Blood count, serum lipid spectrum, complement components C4 and C3a, vascular endothelial growth factor (VEGF), S100B protein, NR2 antibodies (NR2Ab), and total antioxidant status (TAS), as well as plasma fibrinogen, and D-dimer levels and activated partial thromboplastin time (APTT) were assessed. Serum trace elements were analyzed using inductively coupled plasma mass spectrometry. AIS patients were characterized by significantly increased fibrinogen, D-dimer, TG, C3a, C4, NR2Ab, and VEGF levels. The leukocyte count, erythrocyte sedimentation rate and serum atherogenic index were also increased in stroke patients. Oppositely, TAS and APTT values, bleeding and blood coagulation time were decreased. AIS patients were characterized by significantly decreased serum Fe and Co concentrations, whereas the level of Cu, I, Li, Mn, Se, Zn, As, Pb, Ni, and especially V and B in serum was significantly increased. Serum V and B tightly correlated with the procoagulant state and inflammatory markers. Multiple regression analysis revealed a significant inverse association between serum Se levels and stroke markers after adjustment for covariates. Therefore, it is hypothesized that elements like vanadium and boron may be closely involved in stroke pathogenesis by modulation of hemostasis and inflammation, whereas the observed increase in Se levels may be considered as a compensatory reaction.

Relation of serum γ-glutamyl transferase activity with copper in an adult population

Background:

The aim of this study was to evaluate the relationship between serum γ-glutamyl transferase (γ-GGT) activity and serum copper in an adult population.

Methods:

We analyzed 281 adult subjects who regularly attended the physical examination center at the Affiliated Hospital of Youjiang Medical University for Nationalities.

Results:

The demographic and laboratory data of the participants were divided into two groups according to the median of serum γ-GGT activity. Serum copper concentrations in individuals with higher γ-GGT levels were significantly increased compared with those with lower γ-GGT concentrations (9.9±2.41 vs. 11.2±3.36 μmol/L, p<0.001). There was a positive correlation between serum γ-GGT activity and copper in all eligible subjects (r=0.198, p=0.001). Further, serum γ-GGT maintained a positive correlation with serum copper in both males and females (r=0.322, p<0.001; r=0.230, p=0.010). The results of multiple linear regression analysis showed that serum γ-GGT maintained a significantly positive correlation with copper after adjusting for multiple potential confounders (b=0.464, p=0.001).

Conclusions:

This study suggests that serum γ-GGT activity is correlated with copper in the study population, indicating that serum γ-GGT may be a biomarker to evaluate serum copper levels in an adult population.

Serum Trace Element Profiles, Prolactin, and Cortisol in Transient Ischemic Attack Patients

The primary aim of the present study was to assess the association between trace element status, brain damage biomarkers, cortisol, and prolactin levels in transient ischemic attack (TIA) patients. Ten male and 10 female TIA patients were involved in this study. Age, gender, and BMI-matched volunteers served as the respective control group. Serum samples were examined for complement components C4 and C3a, vascular endothelial growth factor (VEGF), S100B, NR2 antibodies (NR2Ab), total antioxidant status (TAS), cortisol, and prolactin. Trace element concentration in serum samples was assessed using inductively coupled plasma mass spectrometry at NexION 300D. The obtained data indicate that both male and female TIA patients were characterized by the increased C4 and prolactin concentrations. At the same time, serum VEGF levels were elevated in only men, whereas TAS values were decreased in women with TIA. Serum cortisol concentrations were significantly increased only in female TIA patients. Men and women with TIA were characterized by a 32 and 44 % decrease in serum Fe content. A two- and threefold increase in serum V content was observed in TIA females and males, respectively. Women with TIA had 60 % higher values of serum B, whereas male patients were characterized by a sevonfold increase in boron content in comparison to the control values. TIA also resulted in decreased serum Cu content in women and elevation of I, Li, Mn, Se, Zn, As, Pb, Ni, and Sr levels in men. Correlation analysis revealed a significant association between trace elements concentration and the studied parameters.

Translational strategies for neuroprotection in ischemic stroke--focusing on acid-sensing ion channel 1a

Ischemic stroke contributes to the majority of brain injuries and remains to be a leading cause of death and long-term disability. Despite the devastating pathology and high incidence of disease, there remain only few treatment options (TPA and endovascular procedures), which may be hampered by time-dependent administration among a variety of other factors. Promising research of glutamate receptor antagonists has been unsuccessful in clinical trial. But, the mechanism by which glutamate receptors initiate injury by excessive calcium overload has spurred investigation of new and potentially successful candidates for stroke therapy. Acid-sensing ion channels (ASICs) may contribute to poor stroke prognosis due to localized drop in brain pH, resulting in excessive calcium overload, independent of glutamate activation. Accumulating studies targeting ASICs have underscored the importance of understanding inhibition, regulation, desensitization, and trafficking of this channel and its role in disease. This review will discuss potential directions in translational ASIC research for future stroke therapies.

Serum levels of trace elements and heavy metals in patients with acute hemorrhagic stroke

Trace elements are essential components of biological structures, but alternatively, they can be toxic at concentrations beyond those necessary for their biological functions. Changes in the concentration of essential trace elements and heavy metals may affect acute hemorrhagic stroke. The aim of this study was to measure serum levels of essential trace elements [iron (Fe), zinc (Zn), manganese (Mn), copper (Cu), and magnesium (Mg)] and heavy metals [cobalt (Co), cadmium (Cd), and lead (Pb)] in patients with acute hemorrhagic stroke. Twenty-six patients with acute hemorrhagic stroke and 29 healthy controls were enrolled. Atomic absorption spectrophotometry (UNICAM-929) was used to measure serum Fe, Cu, Pb, Cd, Zn, Co, Mn and Mg concentrations. Serum Cd, Pb and Fe levels were significantly higher in patients with acute hemorrhagic stroke than controls (p < 0.001), while serum Cu, Zn, Mg and Mn levels were significantly lower (all p < 0.001). However, there was no significant difference between the groups with respect to serum Co levels (p > 0.05). We first demonstrate increased Cd, Pb, and Fe levels; and decreased Cu, Zn, Mg, and Mn levels in patients with acute hemorrhagic stroke. These findings may have diagnostic and prognostic value for acute hemorrhagic stroke. Further studies are required to elucidate the roles of trace elements and heavy metals in patients with acute hemorrhagic stroke.

Serum albumin levels in ischemic stroke and its subtypes: correlation with clinical outcome

OBJECTIVE

Previous studies have associated low serum albumin levels with poor outcome in ischemic stroke. Animal studies also demonstrated neuroprotective effects of serum albumin in focal ischemia. However, there are very limited studies on the association of serum albumin levels with stroke outcome in ischemic stroke divided into subtypes. The present study was carried out to investigate the association of serum albumin levels with outcome in ischemic stroke and its subtypes.

METHODS

The study involved 560 patients. Serum albumin levels were estimated and follow-up interviews were conducted at 3 mo postevent to determine stroke outcome. The association between serum albumin levels and stroke outcome was evaluated by multiple logistic regression analysis after adjustment for potential confounders.

RESULTS

Low levels of albumin associated significantly with poor outcome (score of >3 on the modified Rankin Scale). The adjusted odds ratio was 1.972 (95% confidence interval, 1.103-4.001; P < 0.001). The recurrence of stroke and death rate also was high in patients with low levels of albumin compared with patients with elevated levels of albumin. The reduced level of serum albumin associated significantly with poor outcome in all the stroke subtypes classified according to TOAST (Trial of ORG 10172 in Acute Stroke Treatment).

CONCLUSIONS

Relatively high serum albumin levels in acute stroke decrease poor outcome.

Imaging free zinc levels in vivo - what can be learned?

Our ever-expanding knowledge about the role of zinc in biology includes its role in redox modulation, immune response, neurotransmission, reproduction, diabetes, cancer, and Alzheimers disease is galvanizing interest in detecting and monitoring the various forms of Zn(II) in biological systems. This paper reviews reported strategies for detecting and tracking of labile or "free" unchelated Zn(II) in tissues. While different bound structural forms of Zn(II) have been identified and studied in vitro by multiple techniques, very few molecular imaging methods have successfully tracked the ion in vivo. A number of MRI and optical strategies have now been reported for detection of free Zn(II) in cells and tissues but only a few have been applied successfully in vivo. A recent report of a MRI sensor for in vivo tracking of Zn(II) released from pancreatic β-cells during insulin secretion exemplifies the promise of rational design of new Zn(II) sensors for tracking this biologically important ion in vivo. Such studies promise to provide new insights into zinc trafficking in vivo and the critical role of this ion in many human diseases.

Zinc in the central nervous system: From molecules to behavior

The trace metal zinc is a biofactor that plays essential roles in the central nervous system across the lifespan from early neonatal brain development through the maintenance of brain function in adults. At the molecular level, zinc regulates gene expression through transcription factor activity and is responsible for the activity of dozens of key enzymes in neuronal metabolism. At the cellular level, zinc is a modulator of synaptic activity and neuronal plasticity in both development and adulthood. Given these key roles, it is not surprising that alterations in brain zinc status have been implicated in a wide array of neurological disorders including impaired brain development, neurodegenerative disorders such as Alzheimer's disease, and mood disorders including depression. Zinc has also been implicated in neuronal damage associated with traumatic brain injury, stroke, and seizure. Understanding the mechanisms that control brain zinc homeostasis is thus critical to the development of preventive and treatment strategies for these and other neurological disorders.

Clinical significance of serum zinc levels in cerebral ischemia

Background. Zinc mediates several vital physiological, enzymatic and cellular functions. The association between serum zinc and stroke outcome has not been previously evaluated. Methods. This single center retrospective study was conducted on consecutive stroke (n = 158) and TIA (n = 74) patients. We sought to determine whether serum zinc concentrations in patients with acute ischemic strokes were associated with stroke severity and poor functional status at discharge, respectively. Results. Overall, out of the 224 patients analyzed (mean age 67 years), 35.7% patients had low zinc levels (65 mcg/dL). Patients with stroke (n = 152) were more likely to have low zinc levels (OR = 2.62, CI 1.92–3.57, P < .003) compared to patients with TIA (n = 72). For patients with stroke (n = 152), multivariate analysis showed that low serum zinc levels (OR 2.82, CI 1.35–5.91, P = .035) and strokes with admission severe strokes (NIHSS > 8) (OR 2.68, CI 1.1–6.5, P = .03) were independently associated with poor functional status (MRS > 3) at discharge from the hospital. Conclusion. Low serum zinc concentrations are associated with more severe strokes on admission and poor functional status at discharge.