Magnesium research最新文献

Background: The present study aimed to investigate the incidence of preoperative ionized hypomagnesemia and compare with that of total hypomagnesemia.

Methods: This prospective observational study included 536 patients aged >20 years who were scheduled for elective surgery. Total and ionized magnesium levels were evaluated before and after the surgery. Based on these levels, patients were classified into the following groups: ionized hypo- (<0.42 mmol/L), normo- (0.42-0.59 mmol/L) and hypermagnesemia (>0.59 mmol/L), as well as total hypo- (<1.9 mg/dL[0.78 mmol/L]), normo- (1.9-2.7 mg/dL[0.78-1.11 mmol/L]) and hypermagnesemia (>2.7 mg/dL [1.11 mmol/L]). The primary objective was to establish the incidence of preoperative ionized hypomagnesemia.

Results: There was a marked difference between the incidence of preoperative ionized and total hypomagnesemia (28% vs. 19%; p<0.001). The postoperative values of ionized magnesium, ionized calcium, and albumin were significantly lower than the respective preoperative values (p<0.001 for all three variables).

Conclusion: The incidence of hypomagnesemia, determined by ionized magnesium concentration, was higher than that determined by total magnesium concentration.

In the present study, we investigated whether magnesium sulphate activates the L-arginine/NO/cGMP pathway and elicits peripheral antinociception. The male Swiss mice paw pressure test was performed with hyperalgesia induced by intraplantar injection of prostaglandin E2. All drugs were administered locally into the right hind paw of animals. Magnesium sulphate (20, 40, 80 and 160 μg/paw) induced an antinociceptive effect. The dose of 80 μg/paw elicited a local antinociceptive effect that was antagonized by the non-selective NOS inhibitor, L-NOArg, and by the selective neuronal NOS inhibitor, L-NPA. The inhibitors, L-NIO and L-NIL, selectively inhibited endothelial and inducible NOS, respectively, but were ineffective regarding peripheral magnesium sulphate injection. The soluble guanylyl cyclase inhibitor, ODQ, blocked the action of magnesium sulphate, and the cGMP-phosphodiesterase inhibitor, zaprinast, enhanced the antinociceptive effects of intermediate dose of magnesium sulphate. Our results suggest that magnesium sulphate stimulates the NO/cGMP pathway via neuronal NO synthase to induce peripheral antinociceptive effects.

Several recent studies support a role of dysregulated magnesium homeostasis in COVID-19. In the present narrative review, we focus on the neurological aspects of this disease, collectively known as neuroCOVID, and we propose some mechanisms by which alterations of magnesium may contribute to the involvement of the nervous system in the context of SARS-CoV-2 infection. Further fundamental, translational, and clinical research is needed to underpin the potential relationships between altered magnesium status and neuro-COVID, with potentially novel therapeutic implications.

The relationship between magnesium and hypertension has been intensively investigated in the last few decades. Most of the so far reviews were focused on either dietary magnesium or serum magnesium or magnesium supplements. Our goal was to merge these findings with a more comprehensive approach. Internet search was performed in PubMed database without date limits, using the following search terms "dietary magnesium," "serum magnesium," "magnesium supplements," "hypertension," "drinking water," "food," "endothelial dysfunction," "arterial smooth muscle," and "arterial spasms." In general, there exists an inverse dose-dependent relationship between dietary magnesium intake and serum magnesium and the risk of hypertension. A negative correlation has been found between the serum magnesium concentration and Framingham risk score and intima-media carotid thickness and cardiovascular mortality. On the other hand, concentration of extracellular magnesium in the normal range acts as a natural calcium channel blocker, eliminates endothelial dysfunction, increases nitric oxide, and induces direct and indirect vasodilatation. In conclusion, an average magnesium dietary intake is below the recommended values and magnesium supplementation in the prevention and treatment of hypertension might be justified.

To investigate the association between abnormal serum magnesium levels and the prognosis of elderly patients with community-acquired pneumonia (CAP). Methods: A retrospective study was conducted on 1381 elderly patients with CAP in the First Hospital of Qinhuangdao between January 2015 and December 2018. Serum magnesium concentrations in the range of 0.75-1.25 mmol/L were defined as normal. Patients were assigned into normal, hypomagnesemia, and hypermagnesemia groups. The primary outcome was in-hospital mortality, indicating whether a patient died at the time of discharge from the hospital. The percentages of respiratory failure and mechanical ventilation were 18.6% and 10.6 % in the normal group, 29% and 16.5 % in the hypomagnesemia, and 42.9% and 35.7% in the hypermagnesemia groups. The occurrence of shock was 8.5% and 4.5% in the hypomagnesemia group and the normal group. The percentages of the length of stay at ICU were 14.9%, 18.8%, and 57.1% in the hypomagnesemia, normal, and hypermagnesemia groups. The in-hospital mortality rate was 5.3%, 9.1%, and 35.7% in the normal, hypomagnesemia, and hypermagnesemia groups, respectively. The results of univariate analysis showed that the in-hospital mortality in the hypomagnesemia group was 1.790 (95% confidence interval (CI): 1.009∼3.176, P=0.046) times higher than that in the normal group; in the hypermagnesemia group, it was 9.947 (95% CI: 3.238-30.556, P<0.001) times higher than that in the normal group. The results of multivariate logistic regression analysis showed that after adjusting for gender, age, diabetes, heart failure, cerebrovascular disease, cancer, estimated glomerular filtration rate (eGFR), glucose, and CURB-65 score, in the hypomagnesemia group, the in-hospital mortality was 1.746 (95% confidence interval (CI): 0.956∼3.186, P=0.070) times higher than that in the normal group, and 5.689 (95% CI: 1.583- 20.446, P=0.008) times higher in the hypermagnesemia group than that in the normal group. Abnormal serum magnesium levels are strongly associated with in-hospital mortality in elderly patients with CAP. The measurement of serum magnesium levels in elderly patients with CAP at admission may assist clinicians to determine the prognosis of such patients.

Magnesium (Mg) is the second most abundant intracellular cation and plays a significant role in immune system and cardiac protection. Mg deficiency contributes to chronic low-grade inflammation leading to cardiovascular diseases, and low Mg level exacerbates virus-induced inflammation. The aim of the study was to investigate whether serum magnesium level is associated with myocardial damage and prognosis of COVID-19. This was a single-center, observational retrospective study of patients with COVID-19. The study population was divided into two groups according to in-hospital mortality: a survivor group (SG) and a non-survivor group (NSG). Myocardial damage was defined as blood levels of cardiac troponin I (cTnI) above the 99^th percentile upper reference limit. Magnesium, variables regarding inflammation, and myocardial damage were compared between the groups. A total of 629 patients with COVID-19 were included. Mortality rate was 11.85% (n = 82). There were 61 (74.4%) and 294 male patients (53.7%) in NSG and SG, respectively (p = 0.001). The median age of NSG was 64.5 years (min-max: 37-93) and the median age of SG was 56.0 years (min-max: 22-92) (p < 0.001). Median serum magnesium levels of NSG and SG were 1.94 mg/dL (min-max: 1.04-2.87) and 2.03 mg/dL (min-max: 1.18-2.88), respectively (p = 0.027). Median cTnI levels of NSG and SG were 25.20 pg/mL (min-max: 2.10-2240.80) and 4.50 pg/mL (min-max: 0.50-984.3), respectively (p < 0.001). The cTnI levels were lower in those patients whose serum Mg levels were higher than 1.94. Although serum magnesium level was not a predictor for in-hospital mortality, there was a significant negative correlation between magnesemia and myocardial damage.

Magnesium (Mg) supplementation was shown to improve metabolic syndrome (MetS) parameters in hypomagnesemic patients. The current study evaluated the role of Mg in normomagnesemic individuals with MetS. Patients were randomly assigned to 400 mg Mg as Mg citrate or placebo daily for 12 weeks. Blood pressure (BP), HbA1c, plasma concentrations of glucose, Mg and Ca, blood-ionized Mg, serum concentrations of cholesterol, triglycerides, vitamin D, creatinine, interleukin-6, and C-reactive protein were measured at baseline and after 12 weeks. Data were obtained from n = 13 in the Mg supplemented and n = 11 in the placebo group. Mg supplementation led to a significant increase in plasma Mg concentration (0.78 ± 0.07 mmol/L to 0.83 ± 0.07 mmol/L) and a decrease in systolic and diastolic BP (baseline: 145 ± 10/85 ± 3 mmHg; 12 weeks: 121 ± 5/79 ± 3 mmHg). HbA1c decreased significantly in the Mg group (6.43 ± 0.64% to 6.15 ± 0.55%), and the difference in change between placebo and Mg group was significant. Serum vitamin D levels significantly increased only in the Mg group. In normomagnesemic individuals with MetS, oral Mg citrate supplementation reduced HbA1c and BP.

The aim of the study was to evaluate the significance of hypomagnesemia in patients with coronavirus disease 2019 (COVID-19) and clarify its possible pathogenesis. A retrospective cohort study was conducted by reviewing 83 patients hospitalized in Guanggu district, Wuhan Third Hospital, China. Clinical histories, laboratory findings and outcome data were collected. Eighteen patients had hypomagnesemia during hospitalization. Fourteen patients were in the critical group and six died. In the critical group, serum magnesium (0.72 ± 0.15 mmol/L) was much lower than that in the moderate and severe groups. At the same time, we also found that several indicators are correlated with the level of magnesium. The level of magnesium was positively associated with the lymphocyte count (r = 0.203, P = 0.004) and platelet count (r = 0.217, P = 0.002) but negatively related to the levels of CRP (r = -0.277, P = 0.000), LDH (r = -0.185, P = 0.011) and α-hydroxybutyrate dehydrogenase (r = -0.198, P = 0.008) in the critical group. Hypomagnesemia might increase symptoms and may be associated with mortality in COVID-19 by affecting enzyme activity and activating the inflammatory response. Thus, magnesium might play a key role in the pathogenesis of COVID-19.

The hematopoietic U937 cells are able to differentiate into monocytes, macrophages, or osteoclasts when stimulated, respectively, with vitamin D3 (VD3), phorbol 12-myristate 13-acetate (PMA) or PMA plus VD3. We have previously demonstrated that magnesium (Mg) strongly potentiates the osteoclastic differentiation of U937 cells. In this study, we investigated whether such an effect may be ascribed to a capacity of Mg to modulate the monocyte differentiation of U937 cells and/or to an ability of Mg and VD3 to act directly and independently on the early phases of the osteoclastic differentiation. To address this issue, we subjected U937 cells to an individual and combined treatment with Mg and VD3 and then we analyzed, by flow cytometry and quantitative real-time polymerase chain reaction, the expression of a number of genes related to the early phases of the differentiation pathways under consideration. The results obtained indicated that Mg favors the monocyte differentiation of U937 cells induced by VD3 and at the same time, Mg contrasts the inhibitory effect that VD3 exerts on the osteoclastic differentiation in the absence of PMA. The crucial and articulated role played by Mg in diverse pathways of the osteoclastic differentiation of U973 cells is emphasized.