Magnesium research: official organ of the International Society for the Development of Research on Magnesium (MAGNESIUM RES)

Publications in this journal

• Article: Magnesium homeostasis and aging.

  Mario Barbagallo, Mario Belvedere, Ligia J Dominguez
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  ABSTRACT: Aging is very often associated with magnesium (Mg) deficit. Total plasma magnesium concentrations are remarkably constant in healthy subjects throughout life, while total body Mg and Mg in the intracellular compartment tend to decrease with age. Dietary Mg deficiencies are common in the elderly population. Other frequent causes of Mg deficits in the elderly include reduced Mg intestinal absorption, reduced Mg bone stores, and excess urinary loss. Secondary Mg deficit in aging may result from different conditions and diseases often observed in the elderly (i.e. insulin resistance and/or type 2 diabetes mellitus) and drugs (i.e. use of hypermagnesuric diuretics). Chronic Mg deficits have been linked to an increased risk of numerous preclinical and clinical outcomes, mostly observed in the elderly population, including hypertension, stroke, atherosclerosis, ischemic heart disease, cardiac arrhythmias, glucose intolerance, insulin resistance, type 2 diabetes mellitus, endothelial dysfunction, vascular remodeling, alterations in lipid metabolism, platelet aggregation/thrombosis, inflammation, oxidative stress, cardiovascular mortality, asthma, chronic fatigue, as well as depression and other neuropsychiatric disorders. Both aging and Mg deficiency have been associated to excessive production of oxygen-derived free radicals and low-grade inflammation. Chronic inflammation and oxidative stress are also present in several age-related diseases, such as many vascular and metabolic conditions, as well as frailty, muscle loss and sarcopenia, and altered immune responses, among others. Mg deficit associated to aging may be at least one of the pathophysiological links that may help to explain the interactions between inflammation and oxidative stress with the aging process and many age-related diseases.
  Magnesium research: official organ of the International Society for the Development of Research on Magnesium 12/2009; 22(4):235-46.
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  Available from: usda.gov

  Article: Dietary fatty acid composition alters magnesium metabolism, distribution, and marginal deficiency response in rats.

  Forrest H Nielsen
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  ABSTRACT: Based on dietary intake recommendations, magnesium deficiency commonly occurs throughout the world. However, widespread pathological conditions induced by dietary magnesium deficiency have not been identified. This discrepancy may be caused by other dietary factors ameliorating or exacerbating the response to a marginal magnesium deficiency and/or the length of the deficiency. Thus, a study was performed to determine whether the n-6/n-3 fatty acid composition of the diet affects the response to marginal magnesium deprivation, and whether the effect was dependent upon the length of deprivation. Weanling female rats were fed diets containing 250 mg/kg magnesium in a factorial arrangement with dietary variables of supplemental magnesium at 0 or 250 mg/kg (total of 250 or 500 mg/kg) and fat sources of 75 g/kg corn oil or 65 g/kg fish (menhaden) oil plus 10 g/kg linoleic acid. After 8 and 12 weeks on their respective diets, each rat was placed in a metabolic cage for a 16-hour collection of urine. After 13 weeks, the rats were anesthetized with ether for the collection of plasma and organs. Marginal magnesium deficiency was confirmed by decreased urinary excretion and femur, tibia and vertebrae concentrations of magnesium. Dietary oil influenced the effect of marginal magnesium deficiency on magnesium metabolism, distribution and oxidative stress indicators. Fish oil, but not corn oil, significantly decreased urinary magnesium excretion and increased kidney magnesium concentration. Femur magnesium was significantly decreased by marginal magnesium deficiency in rats fed fish oil but not in rats fed corn oil, and liver magnesium concentration was decreased by fish oil. Marginal magnesium deficiency increased plasma extracellular superoxide dismutase and cysteine (component of glutathione) in rats fed corn oil but not in rats fed fish oil. Urinary prostaglandin E₂ excretion was significantly decreased by marginal magnesium deficiency at 8 weeks, but not at 12 weeks; an increase between weeks 8 and 12 in marginally magnesium-deficient rats fed fish oil caused this change in significance. The findings show that the dietary fatty acid composition affects the response of rats to marginal magnesium deprivation. The findings also indicate that dietary or physiological factors affecting oxidative stress could affect the response to marginal magnesium deficiency, and that a response to a dietary change that takes time to develop, such as an increase in dietary n-3 fatty acids, may result in signs of marginal deficiency being different over time.
  Magnesium research: official organ of the International Society for the Development of Research on Magnesium 12/2009; 22(4):280-8.
• Article: Acid-base conditions regulate calcium and magnesium homeostasis.

  Ragnar Rylander, Tommi Tallheden, Jürgen Vormann
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  ABSTRACT: Previous experimental studies demonstrate that the acid-base balance influences mineral homeostasis by regulating the absorption of calcium and magnesium in the kidneys. No intervention studies are available on population samples. To study the urinary excretion of calcium and magnesium before and after an intervention with the aim of decreasing the acid load. Healthy subjects aged 50-75 years were recruited by advertising. Urinary calcium, magnesium and urea as well as blood pressure were measured before and after the intervention. This comprised taking tablets containing potassium hydrogen carbonate or potassium chloride (placebo) during 7-10 days. There were significant relationships between the urinary excretion of urea and magnesium and calcium before the intervention. Comparing before and after intervention, the change in urinary excretion of urea was related to a change in urinary excretion of calcium and magnesium. There was a significant decrease in systolic as well as diastolic blood pressure both after administration of potassium hydrogen carbonate and citrate. The results confirm previous studies showing a relation between acid conditions in the body and the excretion of calcium and add new data on magnesium. A blood pressure decrease after potassium has been found in previous studies. This suggests an alternative for the treatment of moderately increased levels of blood pressure that should be further explored.
  Magnesium research: official organ of the International Society for the Development of Research on Magnesium 12/2009; 22(4):262-5.
• Article: Magnesium content, total antioxidant status and lipid peroxidation in rainbow trout (Oncorhynchus mykiss Walbaum).

  Ewa Brucka-Jastrzebska, Dorota Kawczuga, Agnieszka Grzelak, Grzegorz Bartosz
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  ABSTRACT: The present study was aimed at evaluating magnesium content, ferric reducing antioxidant power (FRAP) and lipid peroxidation in selected tissues of rainbow trout during their development. For mineral and biochemical assay, samples of liver, kidney, gills and blood were taken from fish. Magnesium concentration ranged between 35.5 and 249.2 mg·kg⁻¹ wt/wt. Most magnesium was found in the gills and the less in kidneys. FRAP values in the examined fish varied from 0.85 to 4.64 nmol Trolox Eq.mg⁻¹ protein. The highest FRAP was observed in the kidneys and the lowest in the gills. Concentration of malondialdehyde (MDA) in the examined tissue homogenates averaged 4.16-11.36 nmol·mg⁻¹ protein. We observed that levels of analyzed parameters increased during growth of the fish.
  Magnesium research: official organ of the International Society for the Development of Research on Magnesium 12/2009; 22(4):273-9.
• Article: Effect of MgSO₄ on FEV₁ in stable severe asthma patients with chronic airflow limitation.

  Alinda M G Zandsteeg, Petra Hirmann, Henk R Pasma, Jan-Peter Yska, Anneke ten Brinke
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  ABSTRACT: The bronchodilating potency of magnesium sulphate (MgSO₄) has been shown in acute asthma exacerbations. We hypothesized that smooth muscle cell relaxation by magnesium might also be beneficial in chronic severe asthma with persistent airflow limitation. To investigate whether nebulised magnesium, administered according to a dosing scheme shown to be effective in acute asthma, induces bronchodilation in stable asthma patients with persistent airflow limitation. In a placebo-controlled, cross-over study, 13 severe asthma patients with postbronchodilator FEV₁ < 75% predicted received either 2.5 mL MgSO₄ 6.4% or placebo in 3 nebulisations at 30 minute intervals. Before the first and 30 minutes after the last inhalation FEV₁, exhaled nitric oxide (NO) in dyspnoea (Borg) were measured. After MgSO₄ treatment no improvement in FEV₁ occurred (56.2 ± 16.8 to 55.4 ± 17.4% predicted [p = 0.5]), neither was a change in exhaled NO or Borg observed (p > 0.1). The changes in FEV₁, NO or Borg were not different between the treatment arms (p ≥ 0.09). Short-term treatment with magnesium inhalations had no direct bronchodilating effect in stable severe asthma patients with persistent airflow limitation. Yet, clinical observations suggest a heterogeneity in response, probably related to treatment intensity, and support further exploration of magnesium administration in these patients.
  Magnesium research: official organ of the International Society for the Development of Research on Magnesium 12/2009; 22(4):256-61.
• Article: Magnesium, calcium and cancer.

  Leopoldo J Anghileri
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  ABSTRACT: Magnesium ion (Mg(2+)) and calcium ion (Ca(2+)) control a diverse and important range of cellular processes, such as gene transcription, cell proliferation, neoplastic transformation, immune response and therapeutic treatment. Their characteristic biologic antagonism makes it important to treat the most important aspects of that competitive behavior together. This synopsis aims to be a useful means of promoting further research on the relationship between both cations and human health affected by environmental conditions.
  Magnesium research: official organ of the International Society for the Development of Research on Magnesium 12/2009; 22(4):247-55.
• Article: Magnesium concentration in the cerebrospinal fluid of mice and its response to changes in serum magnesium concentration.

  Liyuan Sun, Yuki Kosugi, Emiko Kawakami, Ying-Shan Piao, Tomoyo Hashimoto, Kiyomitsu Oyanagi
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  ABSTRACT: Magnesium (Mg) is essential for cell functions such as the transport of calcium and potassium ions, and modulates signal transduction, energy metabolism, and cell proliferation. Although mice have been used as models of various neurological diseases of humans, and for investigating the therapeutic effects of Mg, neither the normal concentration of Mg in cerebrospinal fluid (CSF), nor its response to alteration of the serum level of Mg has yet been reported. The present study investigated the normal Mg concentration in the CSF of C57BL/6J (B6) and ICR mice and its response to elevation of the serum Mg level in B6 mice. In B6 mice, the normal Mg concentration in the CSF was 0.89 ± 0.11 mM, being lower than that in serum, which was 1.38 ± 0.12 mM, whereas in ICR mice the corresponding values were 1.00 ± 0.12 mM and 1.10 ± 0.09 mM, respectively. No significant alteration was found in the CSF of B6 mice injected intraperitoneally with Mg, even though the serum Mg concentration was significantly increased.
  Magnesium research: official organ of the International Society for the Development of Research on Magnesium 12/2009; 22(4):266-72.
• Article: Neutral endopeptidase inhibition enhances substance P mediated inflammation due to hypomagnesemia.

  William B Weglicki, Joanna J Chmielinska, Isabel Tejero-Taldo, Jay H Kramer, Christopher F Spurney, Kandan Viswalingham, Bao Lu, I Tong Mak
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  ABSTRACT: During dietary deficiency of magnesium neurogenic inflammation is mediated, primarily, by elevated levels of substance P (SP). The enzyme most specific for degrading this neuropeptide is neutral endopeptidase (NEP). In recent studies we found that pharmacological inhibition of NEP by phosphoramidon resulted in elevated plasma levels of SP and greater oxidative stress. We also observed that hypomagnesemia reduced cardiac and intestinal expression of NEP. In these magnesium-deficient rats increased intestinal permeability and impaired cardiac contractility occurred. In our colony of genetically-engineered NEP knockout mice that have reduced ability to degrade SP, we found increased oxidative stress that was prevented by SP (neurokinin-1) receptor blockade. Thus, we submit that inhibition of NEP by pharmacological, genetic and dietary approaches (magnesium restriction), causes greater neurogenic inflammation that may result in increased intestinal and cardiac dysfunction.
  Magnesium research: official organ of the International Society for the Development of Research on Magnesium 09/2009; 22(3):167S-173S.
• Article: Failure of beta-cell function for compensate variation in insulin sensitivity in hypomagnesemic subjects.

  Luis E Simental-Mendía, Martha Rodríguez-Morán, Fernando Guerrero-Romero
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  ABSTRACT: To evaluate if decreased insulin sensitivity is appropriately compensated by beta-cell function in subjects with hypomagnesemia, 165 individuals, 20 to 65 years of age, were randomly enrolled in a cross-sectional study. Subjects were allocated into groups with and without hypomagnesemia, matched by age, gender, waist circumference, and body mass index. Pregnancy, smoking, alcohol consumption, high blood pressure, type 2 diabetes, chronic diarrhea, renal disease, malignancy, and heavy physical activity were exclusion criteria. Hypomagnesemia was defined by a serum magnesium concentration of < 1.8 mg/dL. As a surrogate of the hyperbolic model of beta-cell function, the relation between Belfiore's index {2/[1 + (Fasting insulin pmol/L x Fasting glucose mmol/L)]} and the HOMA-beta index {20 X Fasting insulin microU/mL /(Fasting glucose mmol/L - 3.5)} was used. The mean Area Under Curve (AUC) was calculated for each group. Although the Belfiore index was significantly lower (0.041 +/- 0.021 and 0.053 +/- 0.030, p = 0.005) and fasting plasma glucose higher (113.6 +/- 23.0 and 106.8 +/- 18.4 mg/dL, p = 0.04) in the subjects with hypomagnesemia, the HOMA-beta index (82.5 +/- 48.5 and 91.2 +/- 79.9, p = 0.32) and insulin levels (8.6 +/- 5.4 and 9.6 +/- 4.8 mciroU/mL, p = 0.17) were similar between the groups studied. The AUC which evaluates the adaptation of beta-cell function to variation in insulin sensitivity was significantly higher in the normo-magnesemic than the hypomagnesemic group (proportion 1:2.5). Results of this study show that the decrease in insulin sensitivity is not appropriately compensated by beta-cell function in individuals with hypomagnesemia; our finding suggests that hypomagnesemia could be linked to inadequate beta-cell compensation.
  Magnesium research: official organ of the International Society for the Development of Research on Magnesium 09/2009; 22(3):151-6.
• Article: Rumen epithelial cells adapt magnesium transport to high and low extracellular magnesium conditions.

  Monika Schweigel, Judith Kuzinski, Carolin Deiner, Martin Kolisek
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  ABSTRACT: A protein of approximately 70-kDa was identified as a candidate Na+/Mg2+ exchanger in rumen epithelial cells (REC). Melastatin-related Transient Receptor Potential 7 (TRPM7) and Magnesium Transporter 1 (MagT1) transcripts and, from them, encoded proteins were also detected. The regulation of these Mg transport pathways by extracellular [Mg] changes was the main focus of this study. Therefore, a 24-h pre-incubation of ovine REC in control (1.2 mM), low (0.12 mM)-Mg, and high (5 mM)-Mg medium was performed. Na+/Mg2+ exchangers, TRPM7 and MagT1 abundance and activity were investigated by Western blot analysis, flow cytometry, immunocytochemistry and fluorescence spectroscopic measurements of [Mg2+]i changes. Inhibitors were employed to differentiate Na+/Mg2+ exchanger-mediated (imipramine) and channel-mediated (cobalt(III)hexaammine, nitrendipine) Mg transport. Basal [Mg2+]i (0.40 +/- 0.02 mM) was not influenced by pre-incubation in low- or high-Mg medium. However, compared with control REC (4.1 +/- 0.7 microM/min), such cells showed reduced (2.8 +/- 0.6 microM/min) or elevated (6.4 +/- 0.9 microM/min) Mg extrusion rates that correlated with a decreased (25%) and increased (38%) expression of the putative Na+/Mg2+ exchanger protein, respectively. Low- and high-Mg pre-incubated REC were both characterized by an increased (30-40%) influx capacity. In low-Mg REC, the latter resulted mainly from a strong activation of the TRPM7-related transport component. The data thus clearly demonstrate the intrinsic regulation of REC transmembrane Mg transport.
  Magnesium research: official organ of the International Society for the Development of Research on Magnesium 09/2009; 22(3):133-50.
• Article: Magnesium in major depression.

  Mihai Nechifor
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  ABSTRACT: There are contradictory data regarding the levels of magnesium in patients with major depression (MD) and how antidepressants influence their concentration. Our results show erythrocyte magnesium in patients with MD (44.39 +/- 2.7 mg/L vs. 59.1 +/- 3.2 mg/L in control group, p < 0.05) and only in patients with severe MD (Hamilton score > 23) was a moderate decrease in plasmatic magnesium observed (17.7 +/- 1.5 mg/L vs. 22.9 +/- 3.3 mg/L in control group). Therapy with antidepressants from different groups and with different mechanisms of action, such as amytriptiline (25 mg x 3/day per os, 4 weeks) and sertraline (50 mg x 3/day per os, 4 weeks) leads to a significant increase of magnesium concentration in erythrocytes (57.6 +/- 4.5 mg/L after amytriptiline, respectively 56.9 +/- 3.2 mg/L after sertraline, p < 0.05 vs. before therapy). At the same time, in patients with MD, plasmatic levels of zinc were significantly decreased before therapy and increased after treatment with amytriptiline and sertraline (0.68 +/- 0.09 mg/L before treatment vs. 0.9 +/- 0.07 after amytriptiline). There is a positive correlation between concentrations of magnesium in erythrocytes and the clinical evolution of patients with MD. We consider that increasing intracellular concentration is a component of the antidepressant mechanism of sertraline and amytriptiline and maybe of other antidepressants. Anhedonia and autolytic tendencies are important elements of MD symptomatology. We tested the influence of MgCl2 0.2 mM/kg/day on a reward system using conditioned place preference (Panlab) in rats. Our data show a moderate stimulation of the reward system by magnesium (290.6 +/- 27 s time spent in a conditioned compartment before magnesium treatment and 363.3 +/- 16 s after magnesium treatment) that reflects a stimulation of the reward system (RS). We consider that a magnesium-induced stimulation of the RS is an important issue for treating anhedonia in patients with MD. An increase of intracellular magnesium may be part of the mechanism of action of antidepressants.
  Magnesium research: official organ of the International Society for the Development of Research on Magnesium 09/2009; 22(3):163S-166S.
• Article: Effect of Mg2+ on neural activity of rat cortical and hippocampal neurons in vitro.

  Yuriko Furukawa, Nahoko Kasai, Keiichi Torimitsu
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  ABSTRACT: Mg2+ plays an important role in biological functions, similar to that of Ca2+. In terms of neural activity, it is well known that Mg2+ blocks the NMDA receptor. However, the relationship between Mg2+ and neural function has not been well understood. We have investigated the effect of low extracellular Mg2+ concentration ([Mg2+]o) on neural activity in rat cortical and hippocampal neurons by using microelectrode array (MEA) measurements and glutamate measurements, with an enzyme modified MEA-based multi-array sensor. In this study, we investigated the effects of low [Mg2+]o on intracellular Ca2+ concentration ([Ca2+]i) using a confocal laser microscope and a flow cytometer with a fluorescence probe. The results indicate that low [Mg2+]o has an effect on neural activity. The responses of cortical and hippocampal neurons to low [Mg2+]o differed in the developmental period. The results suggest that hippocampal neurons are more sensitive to [Mg2+ than cortical neurons. The glutamate receptor distributions in the cortex and hippocampus may be different. Further investigation is required to understand the mechanisms of the Mg2+ effect on neural activity.
  Magnesium research: official organ of the International Society for the Development of Research on Magnesium 09/2009; 22(3):174S-181S.
• Article: Magnesium in acute and chronic brain injury: an update.

  Robert Vink, Naomi L Cook, Corinna van den Heuvel
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  ABSTRACT: While brain free magnesium levels have been shown to decline in a number of acute and chronic brain pathologies, the mechanisms of such decline and the potential for magnesium administration as a therapeutic intervention are still unclear. In acute brain injury, magnesium therapy has failed in recent clinical trials of trauma, presumably because of an intact blood brain barrier at the time of administration reducing central penetration. Under such conditions, magnesium's peripheral effects on cardiovascular parameters may dominate over the central, and potentially neuroprotective, effects of the compound. In contrast, magnesium has been demonstrated to be beneficial in lacunar strokes, albeit that recent animal studies indicate that this effect is without any significant reduction of lesion size. Postnatal magnesium has also been shown to improve neurological outcome in term neonates with perinatal asphyxia, although this may be limited to cases of mild to moderate brain injury; no effect is observed following severe brain injury. Prenatal magnesium has been reported to be beneficial for outcome in very preterm infants, although this may only be at low doses. Combination therapies are also showing promise in experimental studies, with combined magnesium and mild hypothermia as well as magnesium and polyethylene glycol proving effective in ischemic stroke and in spinal cord injury, respectively. With respect to chronic brain injury, recent results indicate that magnesium deficient mice are susceptible to developing Parkinson's disease, which is consistent with earlier findings that magnesium deficiency over a number of generations is associated with the development of Parkinson's disease. The latter was associated with the appearance of variants of the TRPM channels. Our recent studies have shown that Parkinson's disease is associated with reduced TRPM2 and TRPM7 channel mRNA expression. Taken together, a more complete picture is emerging of the role of magnesium in brain injury, its therapeutic potential as well the mechanisms associated with its decline.
  Magnesium research: official organ of the International Society for the Development of Research on Magnesium 09/2009; 22(3):158S-162S.
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  Available from: ncmls.nl

  Article: Epithelial Mg2+ channel TRPM6: insight into the molecular regulation.

  Jenny van der Wijst, Joost G J Hoenderop, René J M Bindels
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  ABSTRACT: Our understanding of the molecular mechanisms of renal magnesium (Mg2+) handling has greatly enhanced over recent years. This review highlights the regulatory factors controlling Mg2+ homeostasis through its effects on the epithelial Mg2+ channel TRPM6 (Transient Receptor Potential Melastatin subtype 6), the gatekeeper of the body's Mg2+ balance. Drug treatment, acid-base status, and several hormones have been shown to regulate TRPM6 expression, while its channel activity is modified by intracellular Mg2+, pH, and ATP. Recently, epidermal growth factor (EGF) and estrogen have been implicated as magnesiotropic hormones. The stimulation of the EGF receptor (EGFR) leads to an intracellular cascade involving Rac1 that promotes trafficking of TRPM6 to the plasma membrane. Furthermore, long-term EGF treatment upregulates the expression of TRPM6. Estrogen has also been shown to stimulate TRPM6 activity upon short-term treatment, next to its long-term regulatory effect on TRPM6 transcription. TRPM6, and its closest homologue TRPM7, are composed of a Mg2+ -permeable channel fused to an alpha-kinase domain. In the intracellular compartment, the receptor for activated C-kinase (RACK1), the repressor for estrogen receptor activity (REA), and ATP were identified as negative modulators of TRPM6 activity through its alpha-kinase domain. Therefore, the a-kinase domain acts as an indirect player involved in Mg2+ homeostasis by its feedback function in the TRPM6-mediated Mg2+ influx.
  Magnesium research: official organ of the International Society for the Development of Research on Magnesium 09/2009; 22(3):127-32.
• Article: Magnesium in subarachnoid haemorrhage: proven beneficial?

  Walter M van den Bergh
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  ABSTRACT: Subarachnoid haemorrhage (SAH) caused by a ruptured aneurysm accounts for only 5% of strokes, but occurs at a fairly young age and carries a worse prognosis. Delayed cerebral ischaemia (DCI) is an important cause of death and dependence after aneurysmal subarachnoid haemorrhage. The current mainstay of preventing DCI is nimodipine and maintenance of normovolemia, but even with this strategy DCI occurs in a considerable proportion of patients. Magnesium is an inexpensive, easily available neuroprotective agent and has been shown to reduce cerebral vasospasm and infarct volume after experimental SAH. In a subgroup analysis in the Cochrane review of all randomized clinical trials of calcium antagonists in SAH, magnesium reduced the occurrence of DCI and that of poor outcome. Magnesium is a promising agent to prevent the occurrence of secondary ischemia and to improve outcome in patients with SAH. Currently two large phase Il trials are being conducted that will hopefully provide definite evidence whether magnesium treatment is beneficial in SAH patients.
  Magnesium research: official organ of the International Society for the Development of Research on Magnesium 09/2009; 22(3):121-6.
• Article: Effects of chronic administration of calcium-magnesium soft gels on morphine tolerance and dependence in mice.

  Elham Khajehali, Hamid Mirmohammed Sadeghi, Mohammed Rabbani
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  ABSTRACT: The aim of present study was to assess the effects of chronic administration of calcium-magnesium soft gels on the development of morphine tolerance and dependence in mice. Tolerance was assessed using the tail-pinch test and withdrawal signs of morphine were precipitated by injecting naloxone 2 h after the final morphine injection. CalMag capsules were given in final doses of 50/25, 25/12.5 and 12.5/6.25 mg/kg based on calcium/magnesium ratio. Similar doses of Ca and/or Mg were prepared, separately. CalMag at 50/25, 25/12.5 mg/kg and the mixture of calcium and magnesium (Ca + Mg) at 50/25, 25/12.5, 12.5/6.25 mg/kg and calcium at 50, 25 mg/kg significantly reduced the number of jumps. The number of standings was only reduced after the administration of CalMag at 50/25 mg/kg and Ca + Mg at 25/12.5 mg/kg. The development of morphine tolerance was prevented in all drug-treated groups, except the one which received 6.25 mg/kg Mg. The data suggested that combination of calcium and magnesium at 50/25 and 25/12.5 mg/kg prevented the development of tolerance and dependence. It seems that other ingredients of CalMag capsules do not have an important effect on preventing tolerance and withdrawal signs. Compared to the acute effects, chronic administration of Cal-Mag allowed the effective dose to be reduced. Unlike the acute treatment, chronic administration of calcium alone was effective in reducing morphine tolerance and dependence, and magnesium had no significant effect on withdrawal signs, suggestive of some pharmacological adaptations.
  Magnesium research: official organ of the International Society for the Development of Research on Magnesium 07/2009; 22(2):81-8.
• Article: Limited effect of low frequency magnetic fields on the concentrations of calcium, magnesium and fluoride in saliva.

  Piotr Skomro, Krystyna Opalko, Olga Bohdziewicz, Iwona Nocen, Joanna Janiszewska-Olszowska
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  ABSTRACT: To assess the influence of low frequency magnetic fields on the contents of calcium, magnesium and fluoride in saliva. Sixty two patients were subjected to magnetic stimulation with low frequency magnetic fields of mean induction 3 microT at the first intervention and 4 microT at the following fourteen ones. Saliva was sampled before magnetic stimulation and after the 5th, 10th and 15th interventions. The contents of calcium and magnesium ions were measured by means of atomic absorption spectrometry. The content of fluoride was determined using an ion-selective electrode. No statistically significant differences were found between the calcium concentrations before magnetic stimulation and after 5, 10 and 15 interventions. Statistically significant differences in the magnesium concentrations were observed only between 10th and 15th interventions. No statistically significant differences in fluoride concentrations were found. Low frequency magnetic fields have no or weak influences on the content of calcium, magnesium and fluoride in saliva.
  Magnesium research: official organ of the International Society for the Development of Research on Magnesium 07/2009; 22(2):89-92.
• Article: High-magnesium concentration and cytokine production in human whole blood model.

  Wojciech Nowacki, Corinne Malpuech-Brugère, Edmond Rock, Yves Rayssiguier
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  ABSTRACT: The potential influence of magnesium (Mg) on inflammatory responses was assessed using an ex vivo model--human whole blood incubated with and without lipopolysaccharide (LPS). Addition of LPS leads to higher levels of cytokines including TNF-alpha and IL-6. No significant effect of Mg was observed following LPS stimulation whereas high concentration of Mg inhibited the baseline level (without LPS) of TNF-alpha and IL-6 production. This observation contrasts with that of a previous one on Mg-deficient animals. Therefore, the weak efficiency of increasing Mg concentration in this study on the whole blood from healthy volunteers suggests that the efficiency of Mg supplementation on cytokine production induced by endotoxin challenge depends on Mg status.
  Magnesium research: official organ of the International Society for the Development of Research on Magnesium 07/2009; 22(2):93-6.
• Article: Inflammation and elevation of C-reactive protein: does magnesium play a key role?

  Dana E King
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  ABSTRACT: The adverse role played by inflammation in the etiology of humankind's most prevalent chronic diseases compels researchers to work diligently to explore its biologic basis. Recent research supports the concept of an important relationship between dietary factors and inflammation, and in particular the role of magnesium deficiency, however, the specifics of this association are not completely understood. Recent findings from epidemiologic studies support that magnesium intake is inversely associated with C-reactive protein concentration, an important marker of inflammation strongly associated with cardiovascular disease risk. Animal studies have provided many mechanistic possibilities to explain the link between magnesium and inflammation. Further research is needed to understand more completely the role of magnesium in inflammation.
  Magnesium research: official organ of the International Society for the Development of Research on Magnesium 07/2009; 22(2):57-9.