Effects of administration of oral magnesium on plasma glucose and pathological changes in the aorta and pancreas of diabetic rats

Treatment of Resistant Acne Vulgaris in Adolescents Using Dietary Supplementation with Magnesium, Phosphate and Fatty Acids (Omega 6 and 7): Comparison with 13-Cis-Retinoic Acid

The burden of disease associated with acne vulgaris has continued to increase over time in the world population. This continued growth suggests that there is an unmet dermatologic need for this condition worldwide. Potential sequelae of acne, such as scarring, depigmentation, and marked emotional and psychological problems (e.g., low self-esteem), can lead to significant morbidity. The purpose of this study was to investigate whether dietary supplementation with magnesium, phosphate, omega 6 (linoleic acid calcium salt - C18:2 fatty acid Ca salt), and omega 7 (palmitoleic acid calcium salt - C16:1 fatty acid Ca salt) would help patients with acne vulgaris, and to compare with isotretinoin (13-cis retinoic acid). Magnesium has anti-inflammatory properties. Linoleic and palmitoleic acids have bactericidal activity against Staphylococcus aureus and Cutibacterium acnes (formerly known as Propionibacterium acnes). A single-blind randomized study was conducted in which 257 patients were treated with the above dietary supplementation (group A) and 275 patients with isotretinoin (group B) for 6 months. All patients in group A (100%) reported complete regression of symptoms after 6 months of treatment. On the other hand, 187 subjects (68%) in group B reported complete resolution of symptoms during the same period. The difference between the groups (p < 0.05) was statistically significant. The study was approved by the CEP/CONEP. This natural formulation promotes regression and/or cure of acne vulgaris symptoms and has better results than drugs (such as isotretinoin), without significant side effects.

Combination Therapy with GABA and MgSO4 Improves Insulin Sensitivity in Type 2 Diabetic Rat

BACKGROUND

Gamma-aminobutyric acid (GABA) and magnesium sulfate (MgSO₄) play a crucial role in glycemic control. Therefore, we studied the effect of combination therapy with GABA and MgSO₄ to improve insulin sensitivity in diabetes induced by streptozotocin as well as high-fat diet in a diabetic rat model. Design and Methods. Forty randomly selected rats were assigned to four groups: nondiabetic control group was fed the normal diet, insulin-resistant diabetic rat model was induced by streptozotocin and high-fat diet, GABA + MgSO₄ group received GABA and MgSO₄, and insulin group was treated with insulin. Body weight, abdominal fat, blood glucose, serum insulin, and glucagon concentration were measured. The glucose clamp technique, glucose tolerance test, and insulin tolerance test were performed to study insulin sensitivity. Also, the expressions of glucose 6 phosphatase, glucagon receptor, and phosphoenolpyruvate carboxykinase genes in liver were assessed for the gluconeogenesis pathway. Protein translocation and glucose transporter 4 (Glut4) genes expression in muscle were also assessed.

RESULTS

Combination of GABA + MgSO₄ or insulin therapy enhanced insulin level, glycemic control, glucose and insulin tolerance test, some enzymes expression in the gluconeogenesis pathway, body fat, body weight, and glucagon receptor in diabetic rats. Moreover, an increase was observed in protein and gene expression of Glut4. Insulin sensitivity in combination therapy was more than the insulin group.

CONCLUSIONS

GABA and MgSO₄ enhanced insulin sensitivity via increasing Glut4 and reducing the gluconeogenesis enzyme and glucagon receptor gene expressions.

MR-PheWAS for the causal effects of serum magnesium on multiple disease outcomes in Caucasian descent

Magnesium is integral to many physiological processes, whereas variations in its levels, even within the normal range, can have critical implications for health. To explore the broad clinical effects of varying serum magnesium levels, we performed a two-sample Mendelian randomization and phenome-wide association study (MR-PheWAS) in the UK Biobank cohort. In total, MR-PheWAS analysis implicated a causal role of serum magnesium levels in five disease groups and six disease outcomes. In addition, our study indicated the gender-specific effects of nine disease groups/outcomes in MR estimated effects. The protein-protein interaction network demonstrated an interaction between the serum magnesium-associated gene DCDC1 and the cataract- associated gene PAX6. The present study verified several previously reported disease outcomes and identified novel potential disease outcomes for serum magnesium levels. The DCDC1 gene and the PAX6 gene may be the new targets for promoting the treatments of cataracts using magnesium intervention.

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MR-PheWAS implicates a causal role of serum Mg in 11 disease groups/outcomes

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Our study indicates gender-specific effects of 9 disease groups/outcomes

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Mg intervention may promote cataracts treatments through the DCDC1 and PAX6 genes

Magnesium Sulfate Improves Some Risk Factors for Atherosclerosis in Patients Suffering from One or Two Coronary Artery Diseases: A Double-blind Clinical Trial Study

Purpose

Given the beneficial effect of MgSO₄ on the cardiovascular system, this study was designed to investigate the effect of MgSO₄ administration on suppressing some atherosclerotic risk factors in moderate coronary artery disease patients with one or two atherosclerotic vessels.

Patients and Methods

In a randomized double-blind placebo-controlled clinical trial study, 64 patients with moderate coronary artery disease (55–69% stenosis) were selected according to angiography findings. Patients were divided into four groups including patients with one or two atherosclerotic vessels treated with MgSO₄ (Mg-treated-VR1, Mg-treated-VR2, respectively), placebo treated patients with one or two atherosclerotic vessels (Control-VR1, Control-VR2, respectively). The patients received either placebo or MgSO₄ supplement capsule containing 300 mg MgSO₄ for six months on a daily basis. ESR, Ca/Mg ratio, urine Mg level, serum Mg, fibrinogen, homocysteine, uric acid, Na, K, Ca, CRP, T3, T4, TSH, BUN, and Cr concentrations were measured at baseline and every three months.

Results

Serum T3, Ca, K, homocysteine, CRP, and Mg concentrations were significantly improved in Mg-treated groups compared to placebo groups.

Conclusion

The results of this study showed that despite the slight change in serum magnesium level, oral administration of MgSO₄for six months could slightly reduce the serum levels of some inflammatory and vascular factors in moderate coronary artery disease patients.

Effect of Long-term Administration of Oral Magnesium Sulfate and Insulin to Reduce Streptozotocin-Induced Hyperglycemia in Rats: the Role of Akt2 and IRS1 Gene Expressions

The effects of long-term oral administration of magnesium sulfate and insulin on hyperglycemia were investigated using Akt2 and IRS1 gene expression methods in streptozotocin-induced diabetic rats. Fifty rats were randomly divided into five experimental groups: 1, non-diabetic control (NDC); 2, Mg²⁺-treated non-diabetic control (Mg-NDC); 3, chronic diabetic (CD); 4, Mg²⁺-treated chronic diabetic (Mg-CD); and 5, insulin-treated chronic diabetic (Ins-CD). Streptozotocin was used to induce diabetes. The Mg-CD and Mg-NDC groups received 10 g/l of MgSO₄ added to drinking water. The Ins-CD group received 2.5 U/kg of insulin twice a day. Blood glucose level and body weight were measured every week. The intraperitoneal glucose tolerance test (IPGTT) was performed after 16 weeks. MgSO₄ administration improved the blood glucose level and IPGTT. It also increased Akt2 and IRS1 genes as well as protein expression. Insulin lowered the blood glucose level and increased IRS1 gene and protein expression, but did not affect Akt2 gene and protein expression. Glucose reduction after Mg therapy may be mediated, at least partially, via IRS1 and Akt2 genes and protein stimulation. In insulin-treated rats, insulin resistance was not significant due to the absence of Akt2 gene expression.

Effect of oral magnesium sulfate administration on lectin-like oxidized low-density lipoprotein receptor-1 gene expression to prevent atherosclerosis in diabetic rat vessels

AIMS/INTRODUCTION

The purpose of the present study was to investigate the possible effect of oral magnesium sulfate (MgSO4 ) in the reduction of atherosclerosis plaques through inhibition of lectin-like low-density lipoprotein receptor-1 (LOX-1) gene expression in diabetic vessels.

MATERIALS AND METHODS

A total of 50 rats were divided into five groups, including non-diabetic control, Mg-treated non-diabetic control, chronic diabetic, Mg-treated chronic diabetic and insulin-treated chronic diabetic. The induction of diabetes was carried out by streptozotocin. The Mg-treated chronic diabetic and Mg-treated non-diabetic control groups were treated with 10 g/L of MgSO4 added to their drinking water. The insulin-treated chronic diabetic group received 2.5 U/kg of insulin twice per day. The fasting blood glucose level and bodyweight were determined weekly. Blood pressure measurement and the intraperitoneal glucose tolerance test were carried out after 16 weeks, and the plasma levels of Mg, lipid profile and oxidized low-density lipoprotein cholesterol (oxLDL) were determined. The mesenteric bed was isolated and perfused according to the McGregor method. The aorta was isolated for LOX-1 genes and proteins expression, and pathological investigation.

RESULTS

MgSO4 administration improved blood pressure, sensitivity to phenylephrine, intraperitoneal glucose tolerance test, lipid profile and plasma ox-LDL level, and also lowered the blood glucose level to the normal range, and decreased LOX-1 gene and protein expressions. Insulin decreased blood pressure, sensitivity to phenylephrine, blood glucose, lipid profiles and plasma oxLDL level, but it did not decrease LOX-1 gene and protein expressions.

CONCLUSIONS

The present findings suggested that MgSO4 improves blood pressure and vessel structure through decreasing oxLDL, and LOX-1 gene and protein expressions; however, insulin did not repair vessel structure, and LOX-1 gene and protein expressions.

Oral herbal supplement containing magnesium sulfate improve metabolic control and insulin resistance in non-diabetic overweight patients: A randomized double blind clinical trial

Background: Magnesium deficiency plays a key role in obesity and decreases insulin sensitivity. In our previous study, significant evidence was provided for the contribution of oral Mg supplement that could improve insulin sensitivity and body weight in animal trials. The purpose of the present study was to investigate the effects of an herbal supplement containing 300 mg magnesium sulfate on lipid profile, as well as insulin resistance and secretion in overweight patients. Methods: Seventy overweight non-diabetic volunteers with Body Mass Index (BMI) >28 kg/m2 were included in a randomized double blind placebo-controlled clinical trial (ethic number HUMS REC.1394.57) and registered in Iranian Registry of Clinical Trials (IRCT2012110124756N2 with registration number 24756). They received either placebo or an herbal supplement capsule containing 300 mg magnesium sulfate (MgSO4) for 6 months on a daily basis. Metabolic control, lipid profile and magnesium status were determined at baseline and every three months. Student t-test, repeated measure ANOVA and ANCOVA were used to compare the groups. Results: There was no significant difference between groups before intervention, but daily Mg supplement for 6 months significantly improved fasting insulin level (6.71±0.11 to 6.27±0.3 three months after Mg therapy, p<0.01 vs. 6.41±0.11 in control group (5.83±0.063) six months after Mg therapy, p< 0.0001), HOMA-IR (1.52±0.03 )in control group to 1.36±0.03 after three months Mg therapy, p<0.05 vs 1.37±0.05 in control group to 1.22±0.02 six months after Mg therapy, p< 0.05), high density lipoprotein cholesterol (HDL) (43.57±0.82 in control group to 43.91±1.92 three months after Mg therapy, p<0.001vs 43.57±0.82 in control group to 46±0.88 six months after Mg therapy, <0.01), triglyceride (TG) (163.17±6.1 in control group to 141.2±5.84 six months after g therapy, p<0.05) and low density lipoprotein cholesterol (LDL) (112.62±3.41 in control group to 104.42±2.35 six months after Mg therapy, p<0.05). Conclusion: Oral herbal supplement containing MgSO4 (300 mg/day) could improve plasma insulin level, lipid profile, and insulin resistance in non-diabetic overweight volunteers.

Effect of magnesium sulfate administration to improve insulin resistance in type 2 diabetes animal model: using the hyperinsulinemic-euglycemic clamp technique

This study attempted to elucidate the possible mechanism of magnesium sulfate (MgSO₄ ) administration on reducing insulin resistance in type 2 diabetic rats. Fifty Wistar rats were divided into five groups: NDC was fed the normal diet, CD received high-fat diet with 35 mg/kg of streptozotocin, CD-Mg animals received MgSO₄ via drinking water, CD-Ins1, and CD-Ins2 animals treated with low or high dose of insulin. Body weight and blood glucose levels were measured weekly. Intraperitoneal glucose tolerance test (IPGTT), insulin tolerance test, and metabolic cage assessment were performed monthly. After 12 weeks, the hyperinsulinemic-euglycemic clamp was performed for all animals and blood sample was taken to measure glycated hemoglobin (HbA1c), plasma insulin, glucagon, calcium, and magnesium levels. Liver and gastrocnemius muscle were isolated to measure glucagon receptor (GR), Glucose 6 phosphatase (G6Pase), Phosphoenolpyruvate carboxykinase (Pepck) and Glucose transporter 4 (Glut4) genes expression and GLUT4 protein translocation into the cell membrane. Consuming of high-fat diet generated insulin-resistant rats. Magnesium or insulin therapy altered insulin resistance, blood glucose, IPGTT, gluconeogenesis pathway, GR, body weight, the percentage of body fat, and HbA1C in diabetic rats. Administrations of MgSO₄ or insulin in Type 2 diabetes mellitus animals increase GLUT4 gene and protein expression. Mg could improve glucose tolerance via stimulation of Glut4 gene expression and translocation and also suppression of the gluconeogenesis pathway and GR gene expression. Mg also increased glucose infusion rate and displayed beneficial effects in the treatment of glucose metabolism and improved insulin resistance.

Magnesium upregulates insulin receptor and glucose transporter-4 in streptozotocin-nicotinamide-induced type-2 diabetic rats

Objective. We investigated the effects of magnesium supplementation on glucose tolerance, insulin sensitivity, oxidative stress as well as the concentration of insulin receptor and glucose transporter-4 in streptozotocin-nicotinamide induced type-2 diabetic (T2D) rats. Methods. Rats were divided into four groups designated as: 1) control (CTR); 2) diabetic untreated (DU); 3) diabetic treated with 1 mg of Mg/kg diet (Mg1-D); and 4) diabetic treated with 2 mg of Mg/kg diet (Mg2-D). T2D was induced with a single intraperitoneal (i.p.) injection of freshly prepared streptozotocin (55 mg/kg) aft er an initial i.p. injection of nicotinamide (120 mg/kg). Glucose tolerance, insulin sensitivity, lipid profile, malondialdehyde (MAD) and glutathione content, insulin receptors (INSR) and glucose transporter-4 (GLUT4), fasting insulin and glucose levels were measured, and insulin resistance index was calculated using the homeostatic model assessment of insulin resistance (HOMA-IR). Results. Magnesium supplementation improved glucose tolerance and lowered blood glucose levels almost to the normal range. We also recorded a noticeable increase in insulin sensitivity in Mg-D groups when compared with DU rats. Lipid perturbations associated T2D were significantly attenuated by magnesium supplementation. Fasting glucose level was comparable to control values in the Mg-D groups while the HOMA-IR index was significantly lower compared with the DU rats. Magnesium reduced MDA but increased glutathione concentrations compared with DU group. Moreover, INSR and GLUT4 levels were elevated following magnesium supplementation in T2D rats. Conclusion. These findings demonstrate that magnesium may mediate effective metabolic control by stimulating the antioxidant defense, and increased levels of INSR and GLUT4 in diabetic rats.

Cisplatin-Induced Nephrotoxicity; Protective Supplements and Gender Differences

Cisplatin (CDDP) has been widely used as a chemotherapeutic agent for solid tumors. The most common side effect of CDDP is nephrotoxicity, and many efforts have been made in the laboratory and the clinic to employ candidate adjuvants to CDDP to minimize this adverse influence. Many synthetic and herbal antioxidants as well as trace elements have been investigated for this purpose in recent years and a variety of positive and negative results have been yielded. However, no definitive supplement has so far been proposed to prevent CDDP-induced nephrotoxicity; however, this condition is gender related and the sex hormone estrogen may protect the kidney against CDDP damage. In this review, the results of research related to the effect of different synthetic and herbal antioxidants supplements are presented and discussed with suggestions included for future work.

Protective effect of magnesium on renal function in STZ-induced diabetic rats

Background

Diabetic nephropathy is a serious complication of T1D (type one diabetes mellitus). Persistent hyperglycemia and subsequent hypomagnesemia is believed to develop kidney damage by activation of oxidative stress. We conducted this study to investigate the renoprotective effect of magnesium sulfate (MgSO₄) on renal histopathology and oxidative stress in diabetic rats.

Methods

The study included 70 male rats. The animals were divided into seven groups: control (CRL), control receiving MgSO₄ (CRL + Mg1 & CRL + Mg8), diabetic (DM1 & DM8) and diabetic receiving MgSO₄ (DM + Mg1 & DM + Mg8). Rats were given 20 mg/kg (i.p) Streptozocin (STZ) for 5 consecutive days in (MLD) multiple low doses to induce T1D. At day 10 treatment groups were received MgSO₄ (10 g/l) in drinking water, for 1 or 8 weeks. The blood glucose, BUN and creatinine levels were measured. Renal tissue levels of malondialdehyde (MDA) were measured by thiobarbituric acid (TBA) method to evaluate the oxidative stress. Renal histopathology was done using H & E staining method.

Results

Treatment with MgSO₄ significantly decreased the blood glucose in DM + Mg1 and DM + Mg8 groups as compared with DM1 and DM8. Magnesium treatment also decreased serum BUN and tissue level of MDA significantly in both short and long term treatment. The body weight loss and kidney weight to body weight ratio was improved by MgSO₄. Histological results showed there were no differences between DM and DM + Mg groups.

Conclusion

Our findings showed that diabetic nephropathy is associated with high blood glucose level and oxidative stress (significant increase in MDA level). The renal dysfunction and oxidative stress can be improved by magnesium sulfate administration. It is suggested that protection against development of diabetic nephropathy by MgSO₄ treatment involves changes in the blood glucose and oxidative stress.

Mg supplementation protects against ritonavir-mediated endothelial oxidative stress and hepatic eNOS downregulation

Ritonavir (RTV), a prototypical protease inhibitor currently used as a key component of anti-HIV therapy, is known for its endothelial and hepatic toxicity. The effects of RTV and magnesium supplementation on cultured bovine endothelial cell (EC) and rat hepatic endothelial nitric oxide synthase (eNOS) status were investigated. RTV dose-dependently (5-30 µM) decreased EC viability after 48 h; high Mg (2mM) significantly attenuated the lost viability. ECs incubated with 15 µM RTV for 6 to 24h resulted in two- to fourfold elevation of oxidized glutathione and a 25% loss of total glutathione. At 24h, EC superoxide production due to RTV was detected by dihydroethidium staining and increased 41% when quantified by flow cytometry; altered glutathione status and superoxide levels were both substantially reversed by 2mM Mg. RTV reduced eNOS mRNA (-25% at 24 h) and led to decreased eNOS dimer/monomer ratios; nitric oxide-derived products decreased 40%; both changes were attenuated by Mg supplementation. In male Lewis-Brown Norway rats, RTV administration (75 mg/kg/day, 5 weeks) resulted in an 85% increase in plasma 8-isoprostane and a 23% decrease in hepatic eNOS mRNA; concomitantly, eNOS protein decreased 75%, whereas plasma nitrite level was reduced 48%. Dietary Mg supplementation (sixfold higher than control) prevented the eNOS mRNA decrease along with lowering 8-isoprostane and restored the eNOS protein and plasma nitrite levels comparable to controls. In conclusion, Mg attenuates RTV-mediated EC oxidative eNOS dysfunction and downregulation of hepatic eNOS expression; we suggest that Mg can serve as a beneficial adjunct therapeutic against RTV-mediated eNOS toxicity.

Modulation of GLUT4 expression by oral administration of Mg(2+) to control sugar levels in STZ-induced diabetic rats

It has been previously shown that oral magnesium administration decreases the levels of glucose in the plasma. However, the mechanisms are not fully understood. The aim of this study was to determine the potential role of GLUT4 on plasma glucose levels by orally administering magnesium sulfate to diabetic rats. Animals were distributed among 4 groups (n = 10 rats per group): one group served as the non-diabetic control, while the other groups had diabetes induced by streptozotocin (intraperitoneal (i.p.) injection). The diabetic rats were either given insulin by i.p. injection (2.5 U·(kg body mass)(-1)·day(-1)), or magnesium sulfate in their drinking water (10 g·L(-1)). After 8 weeks of treatment, we conducted an i.p. glucose tolerance test (IPGTT), measured blood glucose and plasma magnesium levels, and performed in-vitro and in-vivo insulin level measurements by radioimmunoassay. Gastrocnemius (leg) muscles were isolated for the measurement of GLU4 mRNA expression using real-time PCR. Administration of magnesium sulfate improved IPGTT and lowered blood glucose levels almost to the normal range. However, the insulin levels were not changed in either of the in-vitro or in-vivo studies. The expression of GLU4 mRNA increased 23% and 10% in diabetic magnesium-treated and insulin-treated groups, respectively. Our findings suggest that magnesium lowers blood glucose levels via increased GLU4 mRNA expression, independent to insulin secretion.

Effects of Brown Seaweed (Sargassum polycystum) Extracts on Kidney, Liver, and Pancreas of Type 2 Diabetic Rat Model

The edible seaweed Sargassum polycystum (SP) is traditionally used against several human diseases. This investigation evaluated the effects of two dietary doses of SP ethanolic and aqueous extracts on the pancreatic, hepatic, and renal morphology of type 2 diabetic rats (T2DM). T2DM was induced by feeding rats on high calorie diet followed by a low dose streptozotocin. Changes in the diabetic rat organs in SP treated groups with different doses of extracts were compared with normal rats, diabetic control rats, and metformin treated rats. After 22 days of treatment, the pathological lesions of the livers and kidneys in the diabetic rats were quantitatively and qualitatively alleviated (P < 0.05) by both the SP extracts at 150 mg/kg body weight and by metformin. All the treated diabetic groups revealed marked improvement in the histopathology of the pancreas compared with the control diabetic group. Oral administration of 300 mg/kg body weight of aqueous and ethanolic extracts of SP and metformin revealed pancreas protective or restorative effects. The seaweed extracts at 150 mg/kg body weight reduced the liver and kidney damages in the diabetic rats and may exert tissue repair or restoration of the pancreatic islets in experimentally induced diabetes to produce the beneficial homeostatic effects.

Effect of oral administration of magnesium on Cisplatin-induced nephrotoxicity in normal and streptozocin-induced diabetic rats

Background

Cisplatin (CP) therapy as the most common potent chemotherapeutic process is accompanied by nephrotoxicity. The diabetic state may protect rat kidney against this toxicity, and magnesium (Mg) on the other hand may reduce the glucose level in diabetic animals.

Objectives

Current study was planned to investigate the effect of oral administration of magnesium supplementation on CP-induced nephrotoxicity in normal and Streptozocin (STZ)-induced diabetic rats.

Materials and Methods

Male Wistar rats were divided into seven groups and underwent two experiment protocols. As protocol 1, group 1 was considered as the sham group. Group 2 (CP group) received CP (2 mg/kg/d) for five consecutive days. Group 3 (CP + Mg group) received magnesium sulphate (MgSO4, 10 g/L added to the drinking water) for 10 days and then treated with CP from sixth day. As protocol 2, animals received a single dose of STZ (65 mg/kg i.p.). Three days after diabetes induction, animals were divided into four groups; Groups 4 (D group), 5 (D + CP group), and 7 (D + Mg + CP group) followed the same manner as groups 1 to 3, respectively; and group 6 (D + Mg group) was treated with MgSO4 alone for 10 days. Finally, blood samples were obtained, and all animals were killed for kidney tissue investigation.

Results

CP administration in normoglycemic rats significantly elevated the serum levels of blood urea nitrogen (BUN) and creatinine (Cr) (P < 0.05). However, coadministration of CP and Mg statistically increased the serum levels of BUN and Cr in both normoglycemic and diabetic animals when compared to the rats treated with CP alone (P < 0.05), while the serum level of Mg was significantly increased in nondiabetic groups (P < 0.05). No significant changes were observed in serum and kidney levels of nitrite; as well as the testis weight between all normoglycemic groups, whereas Mg decreased kidney levels of nitrite in diabetic groups when accompanied by CP (P < 0.05). The kidney and serum levels of malondialdehyde (MDA) enhanced significantly in nondiabetic rats treated with Mg and CP (P < 0.05). Kidney tissue damage score (KTDS), kidney weight, and body weight loss were significantly different among normoglycemic groups (P < 0.05), and Mg promoted the KTDS in diabetic animals treated with CP.

Conclusions

Oral Mg supplementation did not protect the CP induced nephrotoxicity in diabetic rats.

Magnesium in disease prevention and overall health

Magnesium is the fourth most abundant mineral and the second most abundant intracellular divalent cation and has been recognized as a cofactor for >300 metabolic reactions in the body. Some of the processes in which magnesium is a cofactor include, but are not limited to, protein synthesis, cellular energy production and storage, reproduction, DNA and RNA synthesis, and stabilizing mitochondrial membranes. Magnesium also plays a critical role in nerve transmission, cardiac excitability, neuromuscular conduction, muscular contraction, vasomotor tone, blood pressure, and glucose and insulin metabolism. Because of magnesium's many functions within the body, it plays a major role in disease prevention and overall health. Low levels of magnesium have been associated with a number of chronic diseases including migraine headaches, Alzheimer's disease, cerebrovascular accident (stroke), hypertension, cardiovascular disease, and type 2 diabetes mellitus. Good food sources of magnesium include unrefined (whole) grains, spinach, nuts, legumes, and white potatoes (tubers). This review presents recent research in the areas of magnesium and chronic disease, with the goal of emphasizing magnesium's role in disease prevention and overall health.

Effects of green tea supplementation on elements, total antioxidants, lipids, and glucose values in the serum of obese patients

The consumption of green tea has been associated with cardiovascular and metabolic diseases. There have been some studies on the influence of green tea on the mineral status of obese subjects, but they have not yielded conclusive results. The aim of the present study is to examine the effects of green tea extract on the mineral, body mass, lipid profile, glucose, and antioxidant status of obese patients. A randomized, double-blind, placebo-controlled study was conducted. Forty-six obese patients were randomly assigned to receive either 379 mg of green tea extract, or a placebo, daily for 3 months. At baseline, and after 3 months of treatment, the anthropometric parameters, blood pressure, and total antioxidant status were assessed, as were the levels of plasma lipids, glucose, calcium, magnesium, iron, zinc, and copper. We found that 3 months of green tea extract supplementation resulted in decreases in body mass index, waist circumference, and levels of total cholesterol, low-density cholesterol, and triglyceride. Increases in total antioxidant level and in zinc concentration in serum were also observed. Glucose and iron levels were lower in the green tea extract group than in the control, although HDL-cholesterol and magnesium were higher in the green tea extract group than in the placebo group. At baseline, a positive correlation was found between calcium and body mass index, as was a negative correlation between copper and triglycerides. After 3 months, a positive correlation between iron and body mass index and between magnesium and HDL-cholesterol, as well as a negative correlation between magnesium and glucose, were observed. The present findings demonstrate that green tea influences the body's mineral status. Moreover, the results of this study confirm the beneficial effects of green tea extract supplementation on body mass index, lipid profile, and total antioxidant status in patients with obesity.

Suppressive effects of natural reduced waters on alloxan-induced apoptosis and type 1 diabetes mellitus

Insulin-producing cells express limited activities of anti-oxidative enzymes. Therefore, reactive oxygen species (ROS) produced in these cells play a crucial role in cytotoxic effects. Furthermore, diabetes mellitus (DM) development is closely linked to higher ROS levels in insulin-producing cells. Hita Tenryosui Water^® (Hita T. W., Hita, Japan) and Nordenau water (Nord. W., Nordenau, Germany), referred to as natural reduced waters (NRWs), scavenge ROS in cultured cells, and therefore, might be a possibility as an alternative to conventional pharmacological agents against DM. Therefore, this study aimed to investigate the role of NRWs in alloxan (ALX)-induced β-cell apoptosis as well as in ALX-induced diabetic mice. NRWs equally suppressed DNA fragmentation levels. Hita T. W. and Nord. W. ameliorated ALX-induced sub-G₁ phase production from approximately 40% of control levels to 8.5 and 11.8%, respectively. NRWs restored serum insulin levels (p < 0.01) and reduced blood glucose levels (p < 0.01) in ALX-induced mice. Hita T. W. restored tissue superoxide dismutase (SOD) (p < 0.05) activity but not tissue catalase activity. Hita T. W. did not elevate SOD or catalase activity in HIT-T15 cells. Nord. W. restored SOD (p < 0.05) and catalase (p < 0.05) activity in both cultured cells and pancreatic tissue to normal levels. Even though variable efficacies were observed between Hita T. W. and Nord. W., both waters suppressed ALX-induced DM development in CD-1 male mice by administering NRWs for 8 weeks. Our results suggest that Hita T. W. and Nord. W. protect against ALX-induced β-cell apoptosis, and prevent the development of ALX-induced DM in experimental animals by regulating ALX-derived ROS generation and elevating anti-oxidative enzymes. Therefore, the two NRWs tested here are promising candidates for the prevention of DM development.

AZT-induced oxidative cardiovascular toxicity: attenuation by Mg-supplementation

Cardiovascular effects of chronic AZT treatment on SD male rats (185 g) fed either a normal Mg diet (0.1% MgO) or a high Mg diet (0.6% MgO) were examined. AZT treatment (1 mg/ml drinking water) for 3 weeks led to a 5.5-fold (0.88 +/- 0.11 nmol/min/10(6) cells, P < 0.05) elevation in neutrophil basal activity of O2(-) production versus controls (0.16 +/- 0.03 nmol/min, assayed ex vivo as SOD-inhibitable cytochrome c reduction). Concomitantly, plasma 8-isoprostane and PGE(2) levels rose 2.1-fold and 3-fold (both P < 0.05), respectively, compared to control; however, RBC GSH decreased 28% (P < 0.02) with GSSG content increased 3-fold, indicative of systemic oxidative stress. High Mg diet substantially attenuated the AZT-induced neutrophil activation by 70% (0.26 +/- 0.05 nmol/min, P < 0.05); reduced plasma 8-isoprostane and PGE(2) to levels comparable to normal; and RBC GSH was restored back to 92% of control. AZT alone caused moderate, but significant vascular inflammatory lesions in the heart (assessed by H&E staining). Immunohistochemical staining revealed significantly higher (about 4-fold) infiltration of CD11b positive cells (WBC surface marker) in the atria and ventricles of AZT-treated rats. However, these inflammatory pathological markers were minimal in samples of rats treated with AZT plus high Mg diet. Moreover, AZT alone significantly (P < 0.02) decreased rat weight gain by 21% at 3 weeks; Mg-supplementation completely prevented (P < 0.05) the weight gain loss due to AZT intake. It is concluded that high dietary Mg may provide beneficial effects against AZT toxicity due to its systemic antioxidative/anti-inflammatory properties.

Minerals as ergogenic aids

Chromium, magnesium, zinc, and selenium are essential minerals for humans. They all are involved in a number of metabolic reactions in the body; many of these reactions are involved in energy metabolism, and hence it is thought that they may exert an ergogenic effect. However, the data on their effects as ergogenic aids have been equivocal. Longitudinal research is required (including supplementation studies) to follow athletes over time and properly evaluate effects of these minerals upon performance. The purpose of this review is to evaluate the ergogenic effects of chromium, magnesium, zinc, and selenium.

Magnesium, the metabolic syndrome, insulin resistance, and type 2 diabetes mellitus

Magnesium is an essential mineral and has been established as a cofactor for over 300 metabolic reactions in the body. Some research has indicated that lower intakes of magnesium and lower serum magnesium concentrations may lead to and are associated with the metabolic syndrome, insulin resistance, and/or type 2 diabetes mellitus. The goal of this review is to examine the research conducted on: 1) magnesium status, metabolic syndrome, insulin resistance, and type 2 diabetes mellitus, and 2) the effects of magnesium intake and/or supplementation on metabolic syndrome, insulin resistance, and type 2 diabetes mellitus. To make this review as current as possible, the majority of research articles reviewed were from 2000 to the present.

Magnesium metabolism in type 2 diabetes mellitus, metabolic syndrome and insulin resistance

Type 2 diabetes is characterized by cellular and extracellular Mg depletion. Epidemiologic studies showed a high prevalence of hypomagnesaemia and lower intracellular Mg concentrations in diabetic subjects. Insulin and glucose are important regulators of Mg metabolism. Intracellular Mg plays a key role in regulating insulin action, insulin-mediated-glucose uptake and vascular tone. Reduced intracellular Mg concentrations result in a defective tyrosine-kinase activity, post-receptorial impairment in insulin action, and worsening of insulin resistance in diabetic patients. Mg deficit has been proposed as a possible underlying common mechanism of the "insulin resistance" of different metabolic conditions. Low dietary Mg intake is also related to the development of type 2 diabetes. Benefits of Mg supplementation on metabolic profile in diabetic subjects have been found in most, but not all clinical studies, and larger prospective studies are needed to support the potential role of dietary Mg supplementation as a possible public health strategy in diabetes risk.

Selected haematological and biochemical parameters of blood in rats after subchronic administration of vanadium and/or magnesium in drinking water

The purpose of these studies was to evaluate the effect of selected vanadium and magnesium doses on certain haematological and biochemical blood parameters in rats. Outbred 2-month-old, albino male Wistar rats received for a period of 6 weeks, as a sole drinking liquid, the following water solutions: group II, sodium metavanadate (SMV) at a concentration of 0.125 mg V/mL; group III, magnesium sulphate (MS) at a concentration of 0.06 mg Mg/mL; and group IV, SMV-MS solution at the same concentrations. The control group received at this time deionized water to drink. It was calculated that group II ingested with drinking water about 10.7 mg V/kg b. w./24 h, group III 6 mg Mg/kg b. w./24 h, and group IV about 9 mg V and 4.5 mg Mg/kg b. w./24 h. The exposure to vanadium alone (group II) led to a statistically significant decrease in body weight gain, food and fluid intakes. Moreover, in the same group of rats a statistically significant decrease in the RBC count, Hb concentration, MCV, and MCH values was demonstrated. Additionally, a statistically significant decrease in the plasma L-ascorbic acid concentration and a significant increase in MDA concentration in blood in this group were found. Instead, after the administration of magnesium alone (group III), a statistically significant decrease in the fluid intake and in the L-ascorbic acid concentration in plasma was noted. Furthermore, in the same group of rats a statistically significant increase in Hb level and in the plasma magnesium concentration was demonstrated. Two-way analysis of variance (ANOVA) did not reveal the interactions between V and Mg.

Oral magnesium administration prevents thermal hyperalgesia induced by diabetes in rats

BACKGROUND

Peripheral neuropathy is a common complication of diabetes mellitus. It has been shown that hyperglycemia may contribute to its development but the exact pathophysiology underlying this complication is not fully understood. Since oral magnesium supplementation can normalize hyperglycemia induced by diabetes in rats, this study was designed to examine the effect of oral magnesium administration on thermal hyperalgesia in streptozocin-induced diabetic rats.

MATERIAL AND METHODS

Twenty-four male adult wistar rats were divided equally into control, magnesium-treated control, diabetic and magnesium-treated diabetic groups. In magnesium-treated diabetic rats, magnesium sulfate (10g/l) was added into the drinking water once diabetes was established (10 days after STZ injection) and continued for 8 weeks. Mg-treated control animals received magnesium sulfate in the same dose and over the same time period. The other two groups; control and diabetic animals, only received tap water. At the end of the 8 weeks, thermal pain threshold was assessed by tail flick test and magnesium and glucose plasma levels were measured in all groups.

RESULT

A significant decrease (p<0.001) in thermal pain threshold and plasma magnesium levels and an increase in plasma glucose levels (p<0.001) were seen in diabetic rats 8 weeks after diabetes induction. After 8 weeks of oral magnesium, thermal hyperalgesia was normalized and plasma magnesium and glucose levels were restored towards normal.

CONCLUSION

It is concluded that oral magnesium administration given at the time of diabetes induction may be able to restore thermal hyperalgesia, magnesium deficiency and hyperglycemia and in diabetic rats.