The association between hypomagnesemia and poor glycaemic control in type 1 diabetes is limited to insulin resistant individuals

Effect of trace elements and nutrients on diabetes and its complications: a Mendelian randomization study

Background

Multiple clinical studies have observed a close relationship between serum trace elements and nutrients and diabetes and its complications, but it remains unclear whether there is a genetic causal effect between serum trace elements and nutrients and diabetes and its complications.

Objective

This study aims to investigate the causal effects of serum trace elements and nutrients on diabetes and its complications using Mendelian randomization methods.

Methods

The single nucleotide polymorphisms of serum trace elements and vitamins, as exposure factors, were sourced from the published UK Biobank database and public databases of genome-wide association studies. The genome-wide association study data of diabetes and its complications, as outcome events, were sourced from the FinnGen Biobank database. Mendelian randomization methods were employed to explore the causal relationships between 9 trace elements and 6 nutrients and diabetes and its complications. The causal relationships were inferred using inverse variance weighting, MR Egger, weighted median, simple model, and weighted model methods. Sensitivity analyses, including heterogeneity tests, horizontal pleiotropy tests, MR-PRESSO tests, and leave-one-out analysis, were conducted to evaluate the robustness of the study results. Finally, trace elements and nutrients with statistical significance in the IVW method and consistent Beta and OR directions in the five methods were selected as exposure factors with causal relationships with diabetes and its complications. This study also used multivariable Mendelian randomization methods to assess the combined effects of multiple exposure factors on the risk of diabetes and its complications.

Results

Mendelian randomization analysis revealed that selenium was linked to an elevated risk of T2D.Vitamin B6 was correlated with an increased risk of neurological complications in type 2 diabetes. Magnesium exhibited a negative causal relationship with the risk of T1D.Carotene was linked to a higher risk of renal complications in T1D.Vitamin B12 showed a negative causal relationship with renal complications in T1D.Carotene was connected to a higher risk of neurological complications in T1D.Potassium and vitamin B6 exhibited negative causal relationships with neurological complications in T1D.Vitamin E showed a negative causal relationship with peripheral circulation complications in T2D.Multivariable Mendelian randomization analysis suggested that vitamin B6 could independently influence neurological complications in both T1D and T2D, apart from other exposure factors. Vitamin B6 could also independently influence renal complications in T1D.Vitamin E could independently influence peripheral circulation complications in T1D, apart from other exposure factors.

Conclusion

The findings from univariable and multivariable Mendelian randomization studies substantiate the causal relationships between trace elements and nutrients and different subtypes of diabetes and their complications. These findings hold significant clinical implications for developing targeted prevention and treatment strategies for diabetes and its complications.

Mitochondrial Dysfunction in Kidney Tubulopathies

Mitochondria play a key role in kidney physiology and pathology. They produce ATP to fuel energy-demanding water and solute reabsorption processes along the nephron. Moreover, mitochondria contribute to cellular health by the regulation of autophagy, (oxidative) stress responses, and apoptosis. Mitochondrial abundance is particularly high in cortical segments, including proximal and distal convoluted tubules. Dysfunction of the mitochondria has been described for tubulopathies such as Fanconi, Gitelman, and Bartter-like syndromes and renal tubular acidosis. In addition, mitochondrial cytopathies often affect renal (tubular) tissues, such as in Kearns-Sayre and Leigh syndromes. Nevertheless, the mechanisms by which mitochondrial dysfunction results in renal tubular diseases are only scarcely being explored. This review provides an overview of mitochondrial dysfunction in the development and progression of kidney tubulopathies. Furthermore, it emphasizes the need for further mechanistic investigations to identify links between mitochondrial function and renal electrolyte reabsorption.

Association and Mechanisms of Proton Pump Inhibitors Use with Type-2Diabetes Mellitus Incidence in Adults: A Systemic Review andMeta-Analysis

BACKGROUND

Proton pump inhibitors (PPIs) are an extensively prescribed class of anti-ulcer drugs. This systematic review aimed to investigate the association between PPI use and the risk of new-onset diabetes mellitus or type 2 diabetes (T2DM) incidence.

METHODS

A comprehensive literature search was conducted in PubMed, Scopus, Cochrane Library, and ClinicalTrials.gov using the search terms "proton pump inhibitor," "proton pump inhibitors," "PPIs," "diabetes mellitus," and "type 2 diabetes" from inception to February 2023. Statistical analyses were performed using the "Review Manager 5.4" version, and a statistically highly significant P-value <0.05 was set.

RESULTS

This systematic review identified 12 studies (8 cohort, 1 RCT, and 3 case-control) with a total of 12, 64, 816 population, and the median age ranged from ≥18 yrs to ≤ 75 yrs. The pooled relative risk (RR) observations of a random-effects meta-analysis model showed that chronic exposure to PPI use has a significant association with T2DM risk incidence (RR, 2.44; 95% confidence interval, 1.31-4.54; I2 = 99%, P < 0.00001). The systematic review findings of the three case-control studies also supported an association of dose-dependent and chronic use of PPIs with an incidence of T2DM among chronic users.

CONCLUSION

The systematic review concludes that chronic PPI exposure increases the risk of T2DM incidence. The authors recommend the shortest possible duration of PPI use and not prescribing PPIs to high-risk prediabetics and those without a compelling indication for PPI use. Regular education to patients regarding adverse reactions with prolonged use may decrease the risk of adverse effects associated with PPIs. The authors suggest that gut dysbiosis, hypergastrinemia, hypomagnesemia, decreased pancreatic secretions and IGF-1 levels, and PXR activation associated with chronic acid suppression among chronic PPI users and the potency of PPIs might explain the association between abnormal glucose metabolism and T2DM incidence. Finally, the authors recommend further randomized controlled trials to investigate the association between PPIs and the risk of new-onset T2DM incidence.

Serum Mg Isotopic Composition Reveals That Mg Dyshomeostasis Remains in Type 1 Diabetes despite the Resolution of Hypomagnesemia

Hypomagnesemia was historically prevalent in individuals with type 1 diabetes mellitus (T1DM), but contemporary results indicate an incidence comparable to that in the general population, likely due to improved treatment in recent decades, resulting in better glycemic control. However, a recent study found a significant difference between the serum Mg isotopic composition of T1DM individuals and controls, indicating that disruptions to Mg homeostasis persist. Significant deviations were also found in samples taken one year apart. To investigate whether the temporal variability in serum Mg isotopic composition is linked to the transient impact of administered insulin, Mg isotope ratios were determined in serum from 15 T1DM individuals before and one hour after insulin injection/meal consumption using multi-collector inductively coupled plasma-mass spectrometry. Consistent with results of the previous study, significant difference in the serum Mg isotopic composition was found between T1DM individuals and 10 sex-matched controls. However, the average difference between pre- and post-insulin injection/meal T1DM samples of 0.05 ± 0.13‱ (1SD) was not significant. No difference was observed for controls before (-0.12 ± 0.16‱) and after the meal (-0.10 ± 0.13‱) either, suggesting a lack of a postprandial Mg isotopic response within one hour of food consumption, and that the timing of the most recent meal may not require controlling for when determining serum Mg isotopic composition.

The Mediterranean Diet for Adolescents with Type 1 Diabetes: A Prospective Interventional Study

The Mediterranean diet (MED) is highly recommended. Medical nutrition therapy is the cornerstone of diabetes treatment. The primary outcome was to evaluate the change in micronutrient intake of youth with type 1 diabetes before and after a 6-month MED intervention; we also assessed adherence and glycemic control. Twenty adolescents, median age 18 years (interquartile range: 15.5-21), median diabetes duration 9 years (7-14), using continuous glucose monitoring devices, received personalized diet regimes based on MED. At 6 months post-intervention, the caloric intake remained unchanged; however, the carbohydrate proportion was lower (p = 0.058), and the intakes of some monounsaturated fats increased (p = 0.049). Sodium intake exceeded the recommended daily allowance by 250% (p = 0.653), before and after the intervention. For blood glucose, the percent TIR (time-in-range, 70-180 mg/dL) improved from 52% (38-60) to 63% (47-71) (p = 0.047). The total insulin dose decreased marginally, from 0.76 u/kg (0.64-0.97) to 0.72 u/kg (0.61-0.89) (p = 0.067). BMI z-score and waist circumference did not change (p = 0.316 and p = 0.161, respectively). Diastolic blood pressure percentile decreased from 73% (68-88) to 69% (50-79) (p = 0.028), and LDL cholesterol from 114 mg/dL (105-134) to 104 mg/dL (96-124) (p = 0.059). The Israeli Mediterranean diet screener score increased, from 8 (7-11) to 13 points (12-14) (p < 0.001). The MED-based intervention in youth with type 1 diabetes is feasible and leads to improvement in monounsaturated fat intake, TIR, and diastolic blood pressure. Other parameters show no change (caloric intake, BMI, and HbA1c).

Magnesium Deficiency and Cardiometabolic Disease

Magnesium (Mg²⁺) has many physiological functions within the body. These include important roles in maintaining cardiovascular functioning, where it contributes to the regulation of cardiac excitation-contraction coupling, endothelial functioning and haemostasis. The haemostatic roles of Mg²⁺ impact upon both the protein and cellular arms of coagulation. In this review, we examine how Mg²⁺ homeostasis is maintained within the body and highlight the various molecular roles attributed to Mg²⁺ in the cardiovascular system. In addition, we describe how nutritional and/or disease-associated magnesium deficiency, seen in some metabolic conditions, has the potential to influence cardiac and vascular outcomes. Finally, we also examine the potential for magnesium supplements to be employed in the prevention and treatment of cardiovascular disorders and in the management of cardiometabolic health.

Hypomagnesemia and Cardiovascular Risk in Type 2 Diabetes

Hypomagnesemia is tenfold more common in individuals with type 2 diabetes (T2D), compared to the healthy population. Factors that are involved in this high prevalence are low Mg2+ intake, gut microbiome composition, medication use and presumably genetics. Hypomagnesemia is associated with insulin resistance, which subsequently increases the risk to develop T2D or deteriorates glycaemic control in existing diabetes. Mg2+ supplementation decreases T2D associated features like dyslipidaemia and inflammation; which are important risk factors for cardiovascular disease (CVD). Epidemiological studies have shown an inverse association between serum Mg2+ and the risk to develop heart failure (HF), atrial fibrillation (AF) and microvascular disease in T2D. The potential protective effect of Mg2+ on HF and AF may be explained by reduced oxidative stress, fibrosis and electrical remodeling in the heart. In microvascular disease, Mg2+ reduces the detrimental effects of hyperglycemia and improves endothelial dysfunction. Though, clinical studies assessing the effect of long-term Mg2+ supplementation on CVD incidents are lacking and gaps remain on how Mg2+ may reduce CVD risk in T2D. Despite the high prevalence of hypomagnesemia in people with T2D, routine screening of Mg2+ deficiency to provide Mg2+ supplementation when needed is not implemented in clinical care as sufficient clinical evidence is lacking. In conclusion, hypomagnesemia is common in people with T2D and is both involved as cause, probably through molecular mechanisms leading to insulin resistance, and consequence and is prospectively associated with development of HF, AF and microvascular complications. Whether long-term supplementation of Mg2+ is beneficial, however, remains to be determined.