Evidence that the etiology of the syndrome containing type 2 diabetes mellitus results from abnormal magnesium metabolism

Gene-nutrient interactions that impact magnesium homeostasis increase risk for neural tube defects in mice exposed to dolutegravir

In 2018, data from a surveillance study in Botswana evaluating adverse birth outcomes raised concerns that women on antiretroviral therapy (ART) containing dolutegravir (DTG) may be at increased risk for neural tube defects (NTDs). The mechanism of action for DTG involves chelation of Mg2+ ions in the active site of the viral integrase. Plasma Mg2+ homeostasis is maintained primarily through dietary intake and reabsorption in the kidneys. Inadequate dietary Mg2+ intake over several months results in slow depletion of plasma Mg2+ and chronic latent hypomagnesemia, a condition prevalent in women of reproductive age worldwide. Mg2+ is critical for normal embryonic development and neural tube closure. We hypothesized that DTG therapy might slowly deplete plasma Mg2+ and reduce the amount available to the embryo, and that mice with pre-existing hypomagnesemia due to genetic variation and/or dietary Mg2+ insufficiency at the time of conception and initiation of DTG treatment would be at increased risk for NTDs. We used two different approaches to test our hypothesis: 1) we selected mouse strains that had inherently different basal plasma Mg2+ levels and 2) placed mice on diets with different concentrations of Mg2+. Plasma and urine Mg2+ were determined prior to timed mating. Pregnant mice were treated daily with vehicle or DTG beginning on the day of conception and embryos examined for NTDs on gestational day 9.5. Plasma DTG was measured for pharmacokinetic analysis. Our results demonstrate that hypomagnesemia prior to conception, due to genetic variation and/or insufficient dietary Mg2+ intake, increases the risk for NTDs in mice exposed to DTG. We also analyzed whole-exome sequencing data from inbred mouse strains and identified 9 predicted deleterious missense variants in Fam111a that were unique to the LM/Bc strain. Human FAM111A variants are associated with hypomagnesemia and renal Mg2+ wasting. The LM/Bc strain exhibits this same phenotype and was the strain most susceptible to DTG-NTDs. Our results suggest that monitoring plasma Mg2+ levels in patients on ART regimens that include DTG, identifying other risk factors that impact Mg2+ homeostasis, and correcting deficiencies in this micronutrient might provide an effective strategy for mitigating NTD risk.

Cost-effectiveness analysis of using oral magnesium supplementation in the treatment of prediabetes

INTRODUCTION

Evidence from clinical trials supports the efficacy of oral magnesium supplementation in the treatment of glucose-related disorders. Thus, we evaluate the cost-effectiveness of using oral magnesium chloride (MgCl₂) in prediabetes treatment.

METHODS

A cost-effectiveness analysis was performed. For such purpose, we used original information from a randomized controlled clinical trial. Analysis was carried out based on a health services provider perspective, a 10-year time horizon, and 3% discount rate for costs and effectiveness. Taking into account risk factor profiles, a Markov micro-simulation model was used, and a probabilistic sensibility analysis was performed.

RESULTS

The oral MgCl₂ was dominant with lower cost and greater effectiveness as compared with placebo. As compared with placebo, 22.3% and 22.0% of men using MgCl₂ did not develop diabetes or cardiovascular disease. The cost per person of using MgCl₂ as compared with placebo, in the individuals without complications, was $2206 versus $4048 USD for men, and $1984 versus $3272 USD for women. The sensitivity analysis confirmed the robustness of the base case.

CONCLUSIONS

Our results suggest that using oral MgCl₂ for at least 4 months, in adults with prediabetes and hypomagnesemia, is a cost-effective option for reducing complications and direct medical costs.

Biological efficacy of zinc oxide nanoparticles against diabetes: a preliminary study conducted in mice

The antidiabetic, hypoglycemic and oral glucose tolerance test (OGTT) activities of zinc oxide nanoparticles (ZnONPs) were assessed in mice. ZnONPs were prepared by reacting Zn(NO3)2.6H2O and NaOH solution at 70°C with continuous stirring and then characterized by transmission electron microscopy (TEM) and scanning electron microscopy (SEM) techniques. Diabetes was induced by the intraperitoneal injection of streptozotocin (STZ) in mice, and then the blood glucose levels were determined by the glucose oxidase method. The experimental results revealed that ZnONPs suggestively (p<0.001) declined the blood glucose levels (39.79%), while these reductions were 38.78% for the cotreatment of ZnONPs and insulin, and 48.60% for insulin, respectively. In the hypoglycemic study, ZnONPs (8 and 14 mg/kg b.w) reduced approximately 25.13 and 29.15% of blood glucose levels, respectively. A similar reduction was found in the OGTT test, which is also a dose- and time-dependent manner. Overall, ZnONPs possess a potential antidiabetic activity, which could be validated by further mechanistic studies.

Anti-dyslipidemic properties of green gold nanoparticle: improvement in oxidative antioxidative balance and associated atherogenicity and insulin resistance

Background

Nowadays, the green synthesis of AuNPs in the presence of plants has been attracted a lot of attention. Herein, in vivo antidiabetic activity of AuNPs synthesized using Ziziphus jujuba in streptozotocin-induced diabetic rats has been evaluated.

Methods

Formation of AuNPs was confirmed by UV-vis, HR-TEM and XRD. Different doses of jujube gold nanoparticles (0.5 and 1 mg/kg) were used to treat streptozotocin-induced diabetic rats in different groups. At the end of experiment (21 days), serum level of fasting blood glucose (FBG), insulin, Body weight, HOMA-IR, vitamin D, ALT, AST, urea, creatinine, lipid profile, prooxidant-antioxidant balance (PAB) and liver oxidative stress markers were determined.

Results

results showed a significant decrease in the level of liver MDA (P = 0.001), fasting blood glucose (P = 0.0001), HOMA-IR (P = 0.0001), ALT (P = 0.0001), AST (P = 0.0001), urea (P = 0.02), Triglycerides (P = 0.002), Total cholesterol (P = 0.0001), PAB (P = 0.0001) and AIP (P = 0.001) and in contrast a significant increase total antioxidant capacity (P = 0.02), insulin (P = 0.03), Body weight (P = 0.0001) and vitamin D (P = 0.0001) in the AuNPs-treated diabetic group compared to the diabetic rats. No significant change was observed in the total thiol group (P = 0.18), LDL-C (P = 0.43), creatinine (P = 0.09) and HDL-C (P = 0.71) level in diabetic rats treated with AuNPs compared to diabetic rats.

Conclusion

The results of this study proves that green AuNPs exerted promising antidiabetic and anti-oxidant properties.

A novel pharmacological approach of herbal mediated cerium oxide and silver nanoparticles with improved biomedical activity in comparison with Lawsonia inermis

Diabetes mellitus is one of the threatening, non-communicable and chronic ailments worldwide since ancient times to the current stage of human existence. The utilization of nanoparticles as a medicine in the treatment of diabetes is an attractive proposition. In the present study, herbal mediated cerium oxide nanoparticles (HMCeO₂ NPs), herbal mediated silver nanoparticles (HMAg NPs) and Lawsonia intermix extract (LIE) was evaluated for them for in-vivo hypoglycemic effect and compared the potency. The resulting HMCeO₂ NPs, HMAg NPs and Lawsonia inermis have been characterized by different analytical equipments such as X-ray Diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), Particle size analyzer (PSA), Field emission scanning electron microscope (FESEM) and High resolution transmission electron microscope (HRTEM). The synthesized NPs and Lawsonia inermis extract were assessed for toxicity by using acute oral toxicity using female albino mice (s) model by following OECD-425 guidelines. In in-vivo hypoglycemic animal model, the male wistar rats with weight varying between 180-200 gms were grouped as: normal control: did not receive any treatment, diabetic control (saline): received a single intraperitoneal dose of Streptozotocin (40 mg/kg), standard: received a single daily oral dose of 50 mg/kg body weight, HMCeO₂ NPs: received single daily oral dose of 100 mg/kg, 200 mg/kg, HMAg NPs: received a single daily oral dose of 100 mg/kg, 200 mg/kg, and Lawsonia inermis: received a single daily oral dose of 100 mg/kg, 200 mg/kg. The herbal mediated NPs were considered safe as they have not shown toxic effects. From the current study results, it may conclude that, due to the advanced biological and pharmacological characters, the HMAg NPs depicted more potent hypoglycemic activity than that of LIE and CeO₂ NPs.

Solvent-free and one-pot synthesis of silver and zinc oxide nanoparticles: Activity toward cell membrane component and insulin signaling pathway in experimental diabetes

OBJECTIVE

To investigate and compare between the effect of both silver nanoparticles (AgNPs) and zinc oxide nanoparticles (ZnONPs) on insulin signaling pathway and insulin sensitivity in experimental diabetes. Preparation of AgNPs and ZnONPs in their solid state were carried out using pullulan (Natural polymer) as both reducing and stabilizing agent. The synthesis of these nanoparticles in a large scale were carried out without using any solvents. The experimental male albino rats received diluted solutions of AgNPs and ZNONPs. After the experimental period, blood was withdrawn; erythrocyte membrane lipids were extracted and fatty acids were determined by HPLC. Oxidant, antioxidant profile and phosphatidylinositol 3-kinase (PI₃K) were estimated.

RESULTS

It was observed that the as synthesized AgNPs and ZnONPs have nearly spherical shape with small size due to the stabilization effect of pullulan as proved by UV-vis spectroscopy (UV-vis), Transmission electron microscy (TEM) and Field emission scanning electron microscopy (FESEM), Zeta potential, Dynamic light scattering (DLS) and X-ray diffraction (XRD) techniques. The average hydrodynamic size of the formed AgNPs was 15 nm which is considered as very small size when compared with that of ZnONPs (above 50 nm). Fasting blood sugar was significantly increased in diabetic group along with elevation of MDA and DNA damage indicating the oxidative properties of streptozotocin. Whereas, the treatment with nanoparticles significantly attenuated these elevations.

CONCLUSION

AgNPs and ZnONPs represent promising materials in attenuating diabetic complications and insulin resistance in experimental diabetes; no Impressive differences were observed between the effect of ZnONPs and AgNPs in this current research.

Effect of the Zinc Oxide Nanoparticles and Thiamine for the Management of Diabetes in Alloxan-Induced Mice: a Stereological and Biochemical Study

This research was carried out to evaluate the antidiabetic effects of zinc oxide nanoparticles (ZnO NPs) and thiamine following experimental diabetes. Fifty-six 6-week-old female mice were used and divided into seven groups of eight animals. Diabetes was induced in fasted mice by using intraperitoneal (IP) injection of alloxan (180 mg/kg). Groups included (I) non-diabetic control, (II) thiamine (30 mg/l, IP), (III) alloxan-induced diabetic mice, (IV) diabetes + ZnO NPs (0.1 mg/kg IP), (V) diabetes + ZnO NPs (0.5 mg/kg IP), (VI) diabetes + ZnO NPs (0.1 mg/kg IP) + thiamine (30 mg/l, IP), and (VII) diabetes + ZnO NPs (0.5 mg/kg IP) + thiamine (30 mg/l, IP). Coincident with pancreas recovery, in diabetic treated mice (groups IV to VII), the mean islet volume, islets per square micrometer, and volume density of the pancreas had increased than in alloxan-induced diabetic mice. ZnO NPs and thiamine induced a decreasing blood glucose, lower serum triglyceride (TG), LDL, and total cholesterol (TC) levels in alloxan-induced diabetic mice treated with ZnO NPs and thiamine, simultaneously increasing HDL as well. In conclusion, ZnO NPs and thiamine are potent antidiabetic factors, and that, these compound supplementation possesses hypoglycemic properties and have effect on serum lipid parameters in diabetes mice.

Alterations of serum trace elements in patients with type 2 diabetes

OBJECTIVE

The aim of the present study is to investigate the association of trace elements and the risk of type 2 diabetes mellitus.

DESIGN AND METHODS

The 1837 participants (637 men and 1200 women) aged 40-70 were from a cross-sectional community-based study performed in downtown Shanghai. All the participants without diabetes mellitus history underwent a 75-g OGTT. The participants with diabetes mellitus took 100g steamed bread as the substitute. The fasting and OGTT 2h or postprandial 2h venous blood samples were collected. Blood glucose levels, fasting serum insulin concentrations, lipid profiles, HbA1C and 19 trace elements including magnesium, copper, zinc and selenium and so on were assayed.

RESULTS

Of all the 1837 studied subjects, 510 subjects had diabetes mellitus (191 male, 319 female). Serum magnesium levels were decreased statistically (p<0.05), but serum copper, zinc and selenium levels were significantly increased in subjects with diabetes mellitus compared to non-diabetic subjects (p<0.01 for copper, p<0.001 for zinc and selenium). Logistic regression analysis showed that serum magnesium was negatively associated with diabetes (p<0.05) and serum copper, zinc, and selenium were all positively associated with diabetes (p<0.05 for copper, p<0.001 for both zinc and selenium). Correlation analysis showed a remarkable correlation between blood glucose, HbA1C and serum magnesium, copper, zinc, and selenium (p<0.01 for zinc, p<0.001 for copper, zinc and selenium).

CONCLUSIONS

Serum magnesium levels are decreased and serum copper, zinc and selenium levels are elevated in patients with type 2 diabetes mellitus.

Low magnesium diet alters distribution of macroelements and trace elements in tissues and organs of female rats

The aim of the present study was to assess whether dietary magnesium deficiency can alter distribution of macroelements and trace elements in different organs and tissues. Experiments were carried out on 12 adult female Wistar rats, which were fed either a diet with low Mg content (≤20mgkg^-1 of diet) (LMgD) or a diet with daily recommended Mg content (≈500mgkg^-1) as control group (CG) for 70 days. On the 70th day of the experiment heart, aorta, femoral skeletal muscle, forebrain, cerebellum, pituitary gland, thyroid gland, ovaries, uterus, liver, kidneys, and spleen were taken for analysis of mineral content. Concentrations of Fe and Ca were measured by inductively coupled plasma-atomic emission spectrometry, and levels of Na, K, Mg, Co, Cu, Zn, Ni, Se, I were determined by inductively coupled plasma mass spectrometry. On the 70th day, LMgD led to significant reduction of Mg level in red blood cells, plasma, aorta, uterus and thyroid gland compared to CG as well as resulted in significant decrease of Mg/Ca ratio in kidneys, spleen and ovaries. Contrary to this, an increase of Mg/Ca ratio was found in cerebellum of LMgD group. Significant decrease of K concentration was shown in aorta of LMgD animals compared to CG whereas myocardial K concentration was increased in LMgD group. Na level was two-fold higher in skeletal muscles of rats that received LMgD in comparison to CG (p=0.006). Increased concentrations of Fe in ovaries and uterus were found in LMgD. Mg restriction did not affect Zn concentration in any of tasted tissues. Se level was higher in spleen and lower in uterus of LMgD animals compared to CG. MgD was accompanied by increased level of Co in skeletal muscles and decreased its level in kidneys and uterus. LMgD feeding was associated with decreased concentrations of Ni in heart, thyroid gland, spleen, uterus and Co in heart, aorta, liver, kidneys, spleen and ovaries. The changes of Mg, K, Co content were accompanied by dramatic (10-fold) decrease of I concentration in aorta of LMgD animals. LMgD causes decrease of I content in ovaries and increase of I level in uterus vs CG. Thus, distribution of macroelements (Ca, Na, K) was weakly affected by Mg restriction that led to the most evident alterations of Co and Ni tissue levels. Moreover, mineral balance of uterus seems to be the most susceptible to low Mg intake. Hypomagnesaemia resulted in significant changes of 5 studied trace elements (Fe, Se, Cu, Ni and Co).

A sub-acute oral toxicity analysis and comparative in vivo anti-diabetic activity of zinc oxide, cerium oxide, silver nanoparticles, and Momordica charantia in streptozotocin-induced diabetic Wistar rats

Type 2 diabetes mellitus (T2DM) is one of the most threatening, non-communicable ailments worldwide.

A fully integrated new paradigm for lithium's mode of action - lithium utilizes latent cellular fail-safe mechanisms

It is proposed that lithium's therapeutic effects occur indirectly by augmenting a cascade of protective "fail-safe" pathways pre-configured to activate in response to a dangerous low cell [Mg⁺⁺] situation, eg, posttraumatic brain injury, alongside relative cell adenosine triphosphate depletion. Lithium activates cell protection, as it neatly mimics a lowered intracellular [Mg⁺⁺] level.

Oral magnesium supplementation improves glycaemic status in subjects with prediabetes and hypomagnesaemia: A double-blind placebo-controlled randomized trial

AIM

This study evaluated the efficacy of oral magnesium supplementation in the reduction of plasma glucose levels in adults with prediabetes and hypomagnesaemia.

METHODS

A total of 116 men and non-pregnant women, aged 30 to 65 years with hypomagnesaemia and newly diagnosed with prediabetes, were enrolled into a randomized double-blind placebo-controlled trial to receive either 30 mL of MgCl2 5% solution (equivalent to 382 mg of magnesium) or an inert placebo solution once daily for four months. The primary trial endpoint was the efficacy of magnesium supplementation in reducing plasma glucose levels.

RESULTS

At baseline, there were no significant statistical differences in terms of anthropometric and biochemical variables between individuals in the supplement and placebo groups. At the end of follow-up, fasting (86.9 ± 7.9 and 98.3 ± 4.6 mg/dL, respectively; P = 0.004) and post-load glucose (124.7 ± 33.4 and 136.7 ± 23.9 mg/dL, respectively; P = 0.03) levels, HOMA-IR indices (2.85 ± 1.0 and 4.1 ± 2.7, respectively; P = 0.04) and triglycerides (166.4 ± 90.6 and 227.0 ± 89.7, respectively; P = 0.009) were significantly decreased, whereas HDL cholesterol (45.6 ± 10.9 and 46.8 ± 9.2 mg/dL, respectively; P = 0.04) and serum magnesium (1.96 ± 0.27 and 1.60 ± 0.26 mg/dL, respectively; P = 0.005) levels were significantly increased in those taking MgCl2 compared with the controls. A total of 34 (29.4%) people improved their glucose status (50.8% and 7.0% in the magnesium and placebo groups, respectively; P < 0.0005).

CONCLUSION

Our results show that magnesium supplementation reduces plasma glucose levels, and improves the glycaemic status of adults with prediabetes and hypomagnesaemia.

Antidiabetic activity of zinc oxide and silver nanoparticles on streptozotocin-induced diabetic rats

The use of nanoparticles in medicine is an attractive proposition. In the present study, zinc oxide and silver nanoparticles were evaluated for their antidiabetic activity. Fifty male albino rats with weight 120 ± 20 and age 6 months were used. Animals were grouped as follows: control; did not receive any type of treatment, diabetic; received a single intraperitoneal dose of streptozotocin (100 mg/kg), diabetic + zinc oxide nanoparticles (ZnONPs), received single daily oral dose of 10 mg/kg ZnONPs in suspension, diabetic + silver nanoparticles (SNPs); received a single daily oral dose of SNP of 10 mg/kg in suspension and diabetic + insulin; received a single subcutaneous dose of 0.6 units/50 g body weight. Zinc oxide and silver nanoparticles induce a significant reduced blood glucose, higher serum insulin, higher glucokinase activity higher expression level of insulin, insulin receptor, GLUT-2 and glucokinase genes in diabetic rats treated with zinc oxide, silver nanoparticles and insulin. In conclusion, zinc oxide and sliver nanoparticles act as potent antidiabetic agents.

Zinc oxide nanoparticles show antidiabetic activity in streptozotocin-induced Type 1 and 2 diabetic rats

Aim: The correlation of diabetes and an imbalance in zinc homeostasis makes zinc-based therapy an attractive proposition. In this study, zinc oxide nanoparticles were evaluated for antidiabetic effects and safety. Materials & methods: Zinc oxide nanoparticles (1, 3 and 10 mg/kg) were tested for antidiabetic activity in streptozotocin-induced Type 1 and 2 diabetic rats. A single-dose pharmacokinetic study, cytotoxicity, hemolysis, acute and subacute toxicity tests, and mechanism-of-action studies were performed. Results: Oral administration of zinc oxide nanoparticles resulted in significant antidiabetic effects – that is, improved glucose tolerance, higher serum insulin (70%), reduced blood glucose (29%), reduced nonesterified fatty acids (40%) and reduced triglycerides (48%). Nanoparticles were systemically absorbed resulting in elevated zinc levels in the liver, adipose tissue and pancreas. Increased insulin secretion and superoxide dismutase activity were also seen in rat insulinoma (RIN-5F) cells. Nanoparticles were safe up to a 300 mg/kg dose in rats. Conclusion: Zinc oxide nanoparticles are a promising antidiabetic agent warranting further studies.

Original submitted 9 July 2012; Revised submitted 27 November 2012; Published online 21 February 2013

Magnesium-deficient high-fat diet: effects on adiposity, lipid profile and insulin sensitivity in growing rats

BACKGROUND & AIMS

To determine if magnesium deficiency aggravates the effects of a high-fat diet in growing rats in terms of obesity, lipid profile and insulin resistance.

METHODS

The study population comprised 48 newly weaned male Wistar Hannover rats distributed into four groups according to diet, namely, control group (CT; n = 8), control diet provided ad libitum; pair-feeding control group (PF; n = 16), control diet but in the same controlled amount as animals that received high-fat diets; high-fat diet group (HF; n = 12), and magnesium-deficient high-fat diet group (HFMg(-); n = 12). The parameters investigated were adiposity index, lipid profile, magnesium status, insulin sensitivity and the phosphorylation of proteins involved in the insulin-signaling pathway, i.e. insulin receptor β-subunit, insulin receptor substrate 1 and protein kinase B.

RESULTS

The HF and HFMg(-) groups were similar regarding gain in body mass, adiposity index and lipid profile, but were significantly different from the PF group. The HFMg(-) group exhibited alterations in magnesium homeostasis as revealed by the reduction in urinary and bone concentrations of the mineral. No inter-group differences were observed regarding glucose homeostasis. Protein phosphorylation in the insulin-signaling pathway was significantly reduced in the high-fat groups compared with the control groups, demonstrating that the intake of fat-rich diets increased insulin resistance, a syndrome that was aggravated by magnesium deficiency.

CONCLUSIONS

Under the experimental conditions tested, the intake of a magnesium-deficient high-fat diet led to alterations in the insulin-signaling pathway and, consequently, increased insulin resistance.

Imipramine inhibition of TRPM-like plasmalemmal Mg2+ transport in vascular smooth muscle cells

Depression is associated with vascular disease, such as myocardial infarction and stroke. Pharmacological treatments may contribute to this association. On the other hand, Mg²⁺ deficiency is also known to be a risk factor for the same category of diseases. In the present study, we examined the effect of imipramine on Mg²⁺ homeostasis in vascular smooth muscle, especially via melastatin-type transient receptor potential (TRPM)-like Mg²⁺-permeable channels. The intracellular free Mg²⁺ concentration ([Mg²⁺]_i) was measured using ³¹P-nuclear magnetic resonance (NMR) in porcine carotid arteries that express both TRPM6 and TRPM7, the latter being predominant. pH_i and intracellular phosphorus compounds were simultaneously monitored. To rule out Na⁺-dependent Mg²⁺ transport, and to facilitate the activity of Mg²⁺-permeable channels, experiments were carried out in the absence of Na⁺ and Ca²⁺. Changing the extracellular Mg²⁺ concentration to 0 and 6 mM significantly decreased and increased [Mg²⁺]_i, respectively, in a time-dependent manner. Imipramine statistically significantly attenuated both of the bi-directional [Mg²⁺]_i changes under the Na⁺- and Ca²⁺-free conditions. This inhibitory effect was comparable in influx, and much more potent in efflux to that of 2-aminoethoxydiphenyl borate, a well-known blocker of TRPM7, a channel that plays a major role in cellular Mg²⁺ homeostasis. Neither [ATP]_i nor pH_i correlated with changes in [Mg²⁺]_i. The results indicate that imipramine suppresses Mg²⁺-permeable channels presumably through a direct effect on the channel domain. This inhibitory effect appears to contribute, at least partially, to the link between antidepressants and the risk of vascular diseases.

Possible association of high urinary magnesium and taurine to creatinine ratios with metabolic syndrome risk reduction in Australian aboriginals

Background. Because of the epidemic of metabolic syndrome (MS) in Australian Aboriginals known for their higher cardiovascular mortality and shorter life expectancy, we analyzed the possible relationship of their MS risks with the current dietary custom. Methods. The subjects were 84 people aged 16–79 years. The health examination was conducted according to the basic protocol of WHO-CARDIAC (Cardiovascular Diseases and Alimentary Comparison) Study. Results. The highest prevalence among MS risks was abdominal obesity (over 60%). After controlling for age and sex, the odds of obesity decreased significantly with high level of urinary magnesium/creatinine ratio (Mg/cre) (OR, 0.11; 95% CI, 0.02–0.57; P < .05). The significant inverse associations of fat intake with Mg/cre and of fast food intake with urinary taurine/creatinine ratio were revealed. Conclusions. The high prevalence of obesity in the Aboriginal people of this area may partly be due to the reduction of beneficial nutrients intake including Mg and taurine.

Trace elements in glucometabolic disorders: an update

Many trace elements, among which metals, are indispensable for proper functioning of a myriad of biochemical reactions, more particularly as enzyme cofactors. This is particularly true for the vast set of processes involved in regulation of glucose homeostasis, being it in glucose metabolism itself or in hormonal control, especially insulin. The role and importance of trace elements such as chromium, zinc, selenium, lithium and vanadium are much less evident and subjected to chronic debate. This review updates our actual knowledge concerning these five trace elements. A careful survey of the literature shows that while theoretical postulates from some key roles of these elements had led to real hopes for therapy of insulin resistance and diabetes, the limited experience based on available data indicates that beneficial effects and use of most of them are subjected to caution, given the narrow window between safe and unsafe doses. Clear therapeutic benefit in these pathologies is presently doubtful but some data indicate that these metals may have a clinical interest in patients presenting deficiencies in individual metal levels. The same holds true for an association of some trace elements such as chromium or zinc with oral antidiabetics. However, this area is essentially unexplored in adequate clinical trials, which are worth being performed.

Intracellular magnesium of obese and type 2 diabetes mellitus children

INTRODUCTION

Magnesium is a critical cofactor in numerous enzymatic reactions. Diabetic patients and obese subjects are often reported to have intracellular magnesium ([Mg(2+)](i)) deficiency. We studied the change of [Mg(2+)](i) in obese children and children with type 2 diabetes mellitus (DM2) after educational intervention or treatment.

METHODS

A total of 25 subjects were included: 13 with simple obesity (10 male, 3 female; mean age 16±8 years, intervention period 1.0±0.6 years), 12 with DM2 (8 male, 4 female; mean age 15±3 years, medication period 1.1±0.7 years), and 16 controls (8 male, 8 female; mean age 17±7 years). By using a fluorescent probe, mag-fura-2, we examined the basal and insulin-stimulated [Mg(2+)](i) of platelets in the blood. Plasma leptin, ghrelin, adiponectin, and resistin levels were determined with the use of enzyme-linked immunosorbent assay (ELISA).

RESULTS

Mean basal [Mg(2+)](i) was lower in the obesity (160±65 μmol/L) and DM2 groups (140±30 μmol/L) compared with the control group (330±28 μmol/L). The elevated [Mg(2+)](i) after insulin stimulation was also lower in these two groups (420±140 μmol/L, and 330±70 μmol/L, respectively) compared with the control group (690±270 μmol/L). In the DM2 group, the basal [Mg(2+)](i) was significantly increased after treatment, while in the obesity group, stimulated [Mg(2+)](i) was increased after intervention.

CONCLUSION

Platelet [Mg(2+)](i) increased after intervention in children with obesity or DM2.

Altered metabolism of copper, zinc, and magnesium is associated with increased levels of glycated hemoglobin in patients with diabetes mellitus

Diabetes mellitus (DM) is associated with the alterations in the metabolism of copper (Cu), zinc (Zn), and magnesium (Mg). The aim of the present study was to investigate plasma levels of these elements in patients with DM and in healthy subjects. Association between glycated hemoglobin and levels of metals was also evaluated. We studied 36 subjects with DM (type 1, 11; type 2, 25) and 34 healthy subjects matched for age, sex, and duration of diabetes. Plasma concentrations of Cu, Zn, and Mg were measured by atomic absorption spectrometry. An imbalance in the levels of studied metals was observed in both type 1 and type 2 DM. We found higher levels of Cu (P < .001) and Cu/Zn ratio (P < .0001) and decreased levels of Zn (P < .01) and Mg (P < .0001) in patients with DM when compared with controls. Negative correlation between Cu and Zn (r = -0.626, P < .0001) was found in patients with DM. Glycated hemoglobin levels were positively correlated with Cu (r = 0.709, P < .001) and Cu/Zn ratio (r = 0.777, P < .001) and inversely correlated with Zn (r = - 0.684, P < .001) and Mg (r = -0.646, P < .001). In conclusion, patients with DM had altered metabolism of Cu, Zn, and Mg; and this may be related to increased values of glycated hemoglobin. We concluded that impaired metabolism of these elements may contribute to the progression of DM and diabetic complications.