Magnesium Replacement to Protect Cardiovascular and Kidney Damage? Lack of Prospective Clinical Trials

Association between dietary magnesium and 10-year risk of a first hard atherosclerotic cardiovascular disease event

BACKGROUND

To test whether dietary magnesium is associated with 10-year risk of a first hard atherosclerotic cardiovascular disease event.

METHODS

In this cross-sectional study, a total of 2980 participants, aged 40 to 79 years, from the National Health and Nutrition Examination Survey 1999-2018 were analyzed. The association between dietary magnesium and 10-year risk of a first hard atherosclerotic cardiovascular disease (ASCVD) event was assessed following adjustment for clinical risk factors, including sex, age, race, educational level, body mass index (BMI), alcohol drinking, smoking, systolic blood pressure (SBP), diastolic blood pressure (DBP), hypertension treated or not, diabetes and low density lipoprotein cholesterol (LDL-C), total energy and dietary fiber. We performed multivariate linear regression models and smooth curve fittings to evaluate the associations between dietary magnesium and 10-year risk of a first hard atherosclerotic cardiovascular disease event.

RESULTS

We observed a significant inverse association between dietary magnesium and predicted 10-year risk of a first hard atherosclerotic cardiovascular disease event (β=-0.01, [95% CI: -0.01, -0.00], P = 0.0256). We divided the 10-year risk into two categories, with a statistically significant reduction of ASCVD risk when the 10-year risk ≥7.5% (β=-0.01, [95% CI: -0.01, -0.00], P = 0.0440).

CONCLUSIONS

Dietary magnesium intake was inversely associated with the predicted 10-year risk of a first hard atherosclerotic cardiovascular disease event.

Pathophysiology and Clinical Impacts of Chronic Kidney Disease on Coronary Artery Calcification

The global prevalence of chronic kidney disease (CKD) has increased in recent years. Adverse cardiovascular events have become the main cause of life-threatening events in patients with CKD, and vascular calcification is a risk factor for cardiovascular disease. Vascular calcification, especially coronary artery calcification, is more prevalent, severe, rapidly progressive, and harmful in patients with CKD. Some features and risk factors are unique to vascular calcification in patients with CKD; the formation of vascular calcification is not only influenced by the phenotypic transformation of vascular smooth muscle cells, but also by electrolyte and endocrine dysfunction, uremic toxin accumulation, and other novel factors. The study on the mechanism of vascular calcification in patients with renal insufficiency can provide a basis and new target for the prevention and treatment of this disease. This review aims to illustrate the impact of CKD on vascular calcification and to discuss the recent research data on the pathogenesis and factors involved in vascular calcification, mainly focusing on coronary artery calcification, in patients with CKD.

Assessment of the Roles of Magnesium and Zinc in Clinical Disorders

The ability and facility of magnesium (Mg2+) and zinc (Zn2+) to interact with phosphate ions confer them the characteristics of essential trace elements. Trace elements are extremely necessary for the basic nucleic acid chemistry of cells of all known living organisms. More than 300 enzymes require zinc and magnesium ions for their catalytic actions, including all the enzymes involved in the synthesis of ATP. In addition, enzymes such as isomerases, oxidoreductases, lyases, transferases, ligases and hydrolases that use other nucleotides to synthesize DNA and RNA require magnesium and zinc. These nucleotides may trigger oxidative damage or important changes against free radicals. In the same way, nucleotides may play an important role in the pathophysiology of degenerative diseases, including in some clinical disorders, where vascular risk factors, oxidative stress and inflammation work to destabilize the patients` homeostatic equilibrium. Indeed, reduced levels of zinc and magnesium may lead to inadequate amount of antioxidant enzymes, and thus, acts as an important contributing factor for the induction of oxidative stress leading to cellular or tissue dysfunction. Hence, the development of zinc or magnesium enzyme inhibitors could be a novel opportunity for the treatment of some human disorders. Therefore, the objective of the present work was to assess the clinical benefits of zinc and magnesium in human health and their effects in some clinical disorders.

Multivitamin/mineral supplementation and the risk of cardiovascular disease: a large prospective study using UK Biobank data

PURPOSE

Despite the widespread use of multivitamin/mineral supplements, the effects of multivitamin/mineral on cardiovascular disease (CVD) remain inconclusive. We aimed to prospectively investigate how multivitamin/mineral use is associated with CVD.

METHODS

This population-based cohort study included 465,278 men and women who participated in the UK Biobank and were free from CVD at baseline. Participants were enrolled between 2006 and 2010 and followed-up until the end of 2018. Data on supplement use including multivitamin/mineral were collected using self-reported questionnaires. Cox proportional hazards models were used to estimate the hazard ratios of CVD events in relation to multivitamin/mineral use.

RESULTS

During the follow-up, we identified 25,772 cases of CVD events, 4754 cases of CVD mortality, 18,728 cases of coronary heart disease, 6726 cases of myocardial infarction, and 4561 cases of stroke. The multivariable-adjusted hazard ratios associated with multivitamin/mineral use were 0.96 (95% CI: 0.93, 0.99) for CVD events, 0.92 (0.86, 1.00) for CVD mortality, 0.96 (0.93, 0.99) for coronary heart disease, and 0.92 (0.86, 0.97) for myocardial infarction. Subgroup analysis suggested that multivitamin/mineral use was associated with a significantly lower risk of CVD events in participants aged < 60 years and in former and current smokers (P for interaction ≤ 0.01). Sensitivity analyses showed no substantial change in the results when we excluded participants who developed CVD events during the first 2 years of follow-up.

CONCLUSION

Multivitamin/mineral supplementation was associated with very modest reductions in CVD events. Age and smoking might modify these associations.

Effects of Dexmedetomidine on Patients Undergoing Laparoscopic Surgery for Colorectal Cancer

BACKGROUND

Pneumoperitoneum during laparoscopic surgery has a systemic impact on the renal system and might contribute to acute kidney injury or postoperative renal dysfunction. However, effective preventive strategies are still lacking. We aimed to explore the effects of dexmedetomidine (DEX) on kidney and other organ function in patients undergoing elective laparoscopic surgery for colorectal cancer.

MATERIALS AND METHODS

Fifty-six patients were randomly enrolled into the Control or DEX group. The DEX group received 1 µg kg^-1 DEX intravenously within 10 min followed by a maintenance dose of 0.5 µg kg^-1 h^-1 infused until 30 min before closing the peritoneum. In the Control group, 0.9% sodium chloride was administered as a placebo. The primary outcome was serum neutrophil gelatinase-associated lipocalin (NGAL) levels reflecting kidney injury. Secondary outcomes included variables reflecting the kidney, intestinal injury and systemic inflammatory response.

RESULTS

NGAL levels were significantly lower in the DEX group than in the Control group at 1 d and 5 d postoperatively (107.5 ± 55.6 ng mL^-1versus 179.5 ± 78.2 ng mL^-1; 70.3 ± 45.8 ng mL^-1versus 135.2 ± 59.6 ng mL^-1, P < 0.001), while the BUN and Cr levels showed no differences between the groups. Serum DAO activity was significantly lower in the DEX group patients 24 h after surgery. Moreover, I-FABP levels were markedly lower at 2 h and 24 h postoperatively in the DEX group than in the Control group (P < 0.001).

CONCLUSIONS

Perioperative DEX administration may potentially confer kidney and intestinal protection during laparoscopic surgery for colorectal cancer patients.

Controlled biodegradation of magnesium alloy in physiological environment by metal organic framework nanocomposite coatings

Magnesium-based implants (MBIs) have recently attracted great attention in bone regeneration due to elastic modulus similar to bone. Nevertheless, the degradation rate and hydrogen release of MBIs in the body have to be tackled for practical applications. In the present study, we present a metal–organic framework (MOF) nanoplates to reduce the degradation rate of AZ91 magnesium alloy. Zeolitic imidazolate frameworks (ZIF-8) with a specific surface area of 1789 m² g⁻¹ were prepared by solvothermal methods, and after dispersion in a chitosan solution (10% w/w), the suspension was electrospun on the surface of AZ91 alloy. Studying the degradation rate in simulated body fluid (SBF) by electrochemical analysis including potentiodynamic polarization and electrochemical impedance spectroscopy reveals that the degradation rate of the surface-modified implants decreases by ~ 80% as compared with the unmodified specimens. The reduced alkalization of the physiological environment and hydrogen release due to the implant degradation are shown. In vitro studies by fibroblasts and MG63 osteosarcoma cells exhibit improved cell adhesion and viability. The mechanisms behind the improved degradation resistance and enhanced bioactivity are presented and discussed. Surface modification of MBIs by MOF-chitosan coatings is a promising strategy to control the biodegradation of magnesium implants for bone regeneration.

Magnesium: The recent research and developments

Magnesium is the fourth most abundant mineral in the human body, which facilitates more than 300 enzymatic reactions. Magnesium is essential for nucleic material and protein synthesis, neuromuscular conduction, cardiac contractility, energy metabolism, and immune system function. Gastrointestinal system and kidneys closely regulate magnesium absorption and elimination to maintain adequate storage of magnesium. Magnesium deficiency has been linked to many diseases and poor health outcomes. Magnesium has also been proven to be an effective therapeutic agent in many diseases, such as bronchial asthma, cardiac arrhythmia, and pre-eclampsia.

The Role of Disturbed Mg Homeostasis in Chronic Kidney Disease Comorbidities

Some of the critical mechanisms that mediate chronic kidney disease (CKD) progression are associated with vascular calcifications, disbalance of mineral metabolism, increased oxidative and metabolic stress, inflammation, coagulation abnormalities, endothelial dysfunction, or accumulation of uremic toxins. Also, it is widely accepted that pathologies with a strong influence in CKD progression are diabetes, hypertension, and cardiovascular disease (CVD). A disbalance in magnesium (Mg) homeostasis, more specifically hypomagnesemia, is associated with the development and progression of the comorbidities mentioned above, and some mechanisms might explain why low serum Mg is associated with negative clinical outcomes such as major adverse cardiovascular and renal events. Furthermore, it is likely that hypomagnesemia causes the release of inflammatory cytokines and C-reactive protein and promotes insulin resistance. Animal models have shown that Mg supplementation reverses vascular calcifications; thus, clinicians have focused on the potential benefits that Mg supplementation may have in humans. Recent evidence suggests that Mg reduces coronary artery calcifications and facilitates peripheral vasodilation. Mg may reduce vascular calcification by direct inhibition of the Wnt/β-catenin signaling pathway. Furthermore, Mg deficiency worsens kidney injury induced by an increased tubular load of phosphate. One important consequence of excessive tubular load of phosphate is the reduction of renal tubule expression of α-Klotho in moderate CKD. Low Mg levels worsen the reduction of Klotho induced by the tubular load of phosphate. Evidence to support clinical translation is yet insufficient, and more clinical studies are required to claim enough evidence for decision-making in daily practice. Meanwhile, it seems reasonable to prevent and treat Mg deficiency. This review aims to summarize the current understanding of Mg homeostasis, the potential mechanisms that may mediate the effect of Mg deficiency on CKD progression, CVD, and mortality.

Increasing the Magnesium Concentration in Various Dialysate Solutions Differentially Modulates Oxidative Stress in a Human Monocyte Cell Line

Oxidative stress is exacerbated in hemodialysis patients by several factors, including the uremic environment and the use of dialysis fluids (DFs). Since magnesium (Mg) plays a key role in modulating immune function and in reducing oxidative stress, we aimed to evaluate whether increasing the Mg concentration in different DFs could protect against oxidative stress in immunocompetent cells in vitro. Effect of ADF (acetate 3 mM), CDF (citrate 1 mM), and ACDF (citrate 0.8 mM + acetate 0.3 mM) dialysates with Mg at standard (0.5 mM) or higher (1, 1.25, and 2 mM) concentrations were assessed in THP-1 monocyte cultures. Reactive oxygen species (ROS) and malondialdehyde (MDA) levels were quantified under basal and uremic conditions (indoxyl sulfate (IS) treatment). Under uremic conditions, the three DFs with 0.5 mM Mg promoted higher ROS production and lipid damage than the control solution. However, CDF and ACDF induced lower levels of ROS and MDA, compared to that induced by ADF. High Mg concentration (1.25 and/or 2 mM) in CDF and ACDF protected against oxidative stress, indicated by reduced ROS and MDA levels compared to respective DFs with standard concentration of Mg. Increasing Mg concentrations in ADF promoted high ROS production and MDA content. Thus, an increase in Mg content in DFs has differential effects on the oxidative stress in IS-treated THP-1 cells depending on the dialysate used.

Magnesium: An old player revisited in the context of CKD-MBD

Chronic kidney disease (CKD) is associated with a wide number of abnormalities in mineral metabolism. Often, these alterations are the leading players in the development of comorbidities associated with CKD, which are risk factors of mortality. In this context, mineral and bone disorder associated with CKD (CKD-MBD) are highlighted, connecting bone, renal, and cardiovascular disorders. Many studies have been led to propose strategies to avoid, reduce, or slow down CKD-MBD progression using different compositions of metallic elements-based P binders such as aluminum, magnesium, or calcium. Magnesium, the aim of this review, has been used by nephrologists to treat CKD-MBD with a variable acceptation due mainly to different results on bone homeostasis. Nowadays, we have new evidence about the efficacy of magnesium supplementation on vascular calcification, renal function, and bone disorders, suggesting potential beneficial effects of Magnesium in the management of CKD-MBD.

Retrospective analysis of the association between intraoperative magnesium sulfate infusion and postoperative acute kidney injury after major laparoscopic abdominal surgery

Magnesium sulfate can be used as a co-adjuvant drug during the perioperative period and has multiple benefits. Recent evidence suggested that perioperative magnesium sulfate infusion may lower the risk of postoperative acute kidney injury (AKI). We investigated the association between intraoperative magnesium sulfate infusion and incidence of AKI after major laparoscopic abdominal surgery. We retrospectively analyzed the medical records of adult patients 20 years or older who underwent elective major laparoscopic abdominal surgery (>2 hours) between 2010 and 2016. We investigated the association between intraoperative magnesium sulfate infusion and the incidence of postoperative AKI until postoperative day (POD) 3 using a multivariable logistic regression analysis. We included 3,828 patients in this analysis; 357 patients (9.3%) received an intraoperative magnesium sulfate infusion and 186 patients (4.9%) developed postoperative AKI by POD 3. A multivariable logistic regression analysis showed that magnesium infusion was associated with a significant decrease (63%) in postoperative AKI (odds ratio, 0.37; 95% confidence interval, 0.14–0.94; P = 0.037). Our study suggested that intraoperative magnesium sulfate infusion is associated with a reduced risk of postoperative AKI until POD 3 for patients who underwent laparoscopic major abdominal surgery. Well-designed, prospective studies should be conducted to further substantiate these findings.

Nattokinase-heparin exhibits beneficial efficacy and safety-an optimal strategy for CKD patients on hemodialysis

Heparin is a widely used anticoagulant in hemodialysis (HD) for patients with chronic kidney disease (CKD); however, it entails the risk of thrombus formation due to heparin-induced thrombocytopenia. Indeed, CKD patients on HD are associated with excessive mortality from cardiovascular disease due to their prothrombotic profile. Therefore, it would be a significant breakthrough to develop a thrombolytic adjuvant that facilitates heparin to achieve its proper anticoagulant efficiency at a much lower dose for greater safety. Nattokinase (NK), a valuable dietary supplement possessing strong fibrinolytic and thrombolytic activity, was reported to interact with heparin and thereby the beneficial efficacy of NK-heparin was investigated herein. NK-heparin induced a synergistic enhancement of clotting time both in vitro and in vivo evaluations, whereas the overall fibrinolytic activity was only marginally enhanced. Moreover, it was demonstrated for the first time that NK induced potent degradation of all three chains of fibrinogen. In particular, NK-heparin markedly reinforced the fibrinolysis activity of NK, which may underlie, at least in part, the mechanism by which NK-heparin benefited their overall thrombolytic and anticoagulant activity. Collectively, we clarified the beneficial combination efficacy of NK and heparin for greater safety, providing a powerful impetus for physicians to administer heparin to a larger portion of patients with CKD.

Hypomagnesemia and hypermagnesemia

Introduction:Magnesium is an essential element which also has pleiotropic effects in humans. Recent studies have altered our interpretation of a disturbed magnesium balance both leading to hypomagnesemia and hypermagnesemia. Methods: a narrative review of their clinical relevance is presented. Results: Although magnesium balance is strictly controlled by the kidneys, hypomagnesemia is fairly common, especially in people with comorbid conditions. Increased renal magnesium wasting, often aggravated by drugs, is commonly found in conditions associated with unfavorable outcomes such as diabetes mellitus and sepsis. Depending on its severity hypomagnesemia may reveal itself by potentially hazardous neurological and cardiovascular symptoms. Intravenous magnesium is an evidence-based treatment of torsades de pointes and preeclampsia irrespective of the presence of preexisting hypomagnesemia. Magnesium deficiency and/or hypomagnesemia has been linked to cardiovascular disease, vascular calcification and endothelial function both in vitro and in vivo. (Severe) hypermagnesemia can be life-threatening but is almost exclusively observed in patients with substantially decreased kidney function associated with high magnesium intake through supplements or magnesium containing cathartics or antacids. Conclusion:It remains unclear whether mild hypermagnesemia confers survival benefit especially in subjects with decreased kidney function. The role of oral magnesium supplementation of chronic mild asymptomatic hypomagnesemia also merits further exploration through interventional studies in various study populations.

Magnesium: Are We Consuming Enough?

Magnesium is essential for maintaining normal cellular and organ function. In-adequate magnesium balance is associated with various disorders, such as skeletal deformities, cardiovascular diseases, and metabolic syndrome. Unfortunately, routinely measured serum magnesium levels do not always reflect total body magnesium status. Thus, normal blood magnesium levels eclipse the wide-spread magnesium deficiency. Other magnesium measuring methods, including the magnesium loading test, may provide more accurate reflections of total body magnesium status and thus improve identification of magnesium-deficient individuals, and prevent magnesium deficiency related complications.