An update on magnesium and bone health

Implant derived high local concentration of magnesium inhibits tumorigenicity of osteosarcoma

Osteosarcoma (OS) is a fatal malignant tumor that occurs in bone, whose main treatment is surgical resection. With anti-tumor and osteogenic effects, Magnesium (Mg) is a promising biodegradable metal for postoperative treatment in OS, however, its anti-OS effect and mechanism still need to be explored. Here, while holding the ability to promote osteogenesis, Mg metal at the same time significantly reduces the proliferation, migration and invasion of various OS cells (UMR106, 143B, K7M2) in vitro. Similarly, it inhibits the growth and lung metastasis of UMR106 induced tumors in xenograft models in vivo. The mRNA-seq analysis shows that Mg significantly inhibits Wnt-pathway (increased APC, Axin2 and GSK3β to induce degradation of β-catenin) in typical OS, which is further verified by western blotting and immunofluorescence analyses. A Mg2+ concentration of 240 mg/L, either from Mg metal extract or Mg salt (MgCl2), equivalently exhibits significantly increased APC, Axin2, GSK3β and decreased β-catenin, and then inhibits tumorigenicity of typical OS cells. This work reveals that a local high concentration of Mg can inhibit OS by down-regulating Wnt-pathway, and meanwhile favors for normal health bone, which demonstrates a new approach and mechanism in the treatment of OS with Mg-based biodegradable metals.

Development of Poly(ether sulfone)/Poly(vinyl alcohol)/Magnesium-Doped Carbon Quantum Dot Scaffolds for Bone Tissue Engineering

Bone tissue engineering plays a critical role in overcoming the limitations of traditional bone grafts and implants by enhancing bone integration and regeneration. In this study, we developed a novel membrane scaffold comprising poly(ether sulfone) (PES), poly(vinyl alcohol) (PVA), and magnesium-doped carbon quantum dots (CQDs.Mg) for potential bone tissue engineering applications. Four distinct scaffold formulations (PE-CM0, PE-CM2, PE-CM3, and PE-CM4) were developed using a film applicator machine. The morphology and porosity of the scaffolds, characterized via scanning electron microscopy (SEM), revealed increased porosity with higher CQDs.Mg content. Fourier transform infrared spectroscopy (FTIR) confirmed the successful integration of functional groups from each component. Water contact angle (WCA) measurements indicated improved hydrophilicity with the addition of CQDs.Mg, which is beneficial for cell attachment and proliferation. Mechanical testing demonstrated that the scaffolds maintained adequate tensile strength and flexibility, with PE-CM3 and PE-CM4 exhibiting superior properties. Swelling assays indicated enhanced water absorption with increased CQDs.Mg content, while 14-day degradation studies showed excellent structural stability. Biocompatibility was also assessed using L929 and NIH3T3 cell lines, with cytotoxicity assays demonstrating nearly 100% cell viability across all samples. These findings suggest that the PES/PVA/CQDs.Mg scaffolds exhibit a promising combination of mechanical robustness, hydrophilicity, and biocompatibility, making them strong candidates for bone tissue engineering applications.

DNA as a promising biomaterial for bone regeneration and potential mechanisms of action

DNA nanotechnology has created new possibilities for the use of DNA in tissue regeneration - an important advance for DNA use beyond its paradigmatic role as the hereditary biomacromolecule. Biomaterials containing synthetic or natural DNA have been proposed for several applications including drug and gene delivery, and more recently, as osteoconductive biomaterials. This review provides an in-depth discussion of studies that have used DNA-based materials for biomineralization and/or bone repair, with expansion on the topic of DNA hydrogels specifically, and the advantages they offer for advancing the field of bone regeneration. Four mechanisms of action for the osteoconductive capabilities of DNA-based materials are discussed, and a proposed model for degradation of these materials and its link to their osteoconductive properties is later presented. Finally, the review considers current limitations of DNA-based materials and summarizes important aspects that need to be addressed for future application of DNA nanotechnology in tissue repair. STATEMENT OF SIGNIFICANCE: Herein we summarize the developing field of DNA-based materials for biomineralization and bone repair, with a focus on DNA hydrogels. We first provide a comprehensive review of different forms of DNA-based materials described thus far which have been shown to enhance bone repair and mineralization (namely DNA coatings, DNA-containing pastes, DNA nanostructures and DNA hydrogels). Next, we describe four different mechanisms by which DNA-based materials could be exerting their osteogenic effect. Then, we propose a novel model that links DNA degradation and osteoconductivity. Lastly, we suggest possible research directions to enhance DNA-based materials for future clinical application. The suggested mechanisms and the proposed model can guide future research to better understand how DNA functions as a mineral- and bone-promoting molecule.

A multinational cross-sectional study on knowledge, attitudes, and practices towards magnesium supplements

Background

Magnesium is a vital mineral with a crucial role in different biochemical reactions. There is a contradicting evidences about its role in maintaining bone, muscle and cardiovascular health. Recently, magnesium supplements gained attention due to claimed effectiveness in improving sleep quality and relieving muscle spasm.

Aim

This study aimed to assess Arab communities' knowledge, attitudes and practices regarding magnesium supplementation.

Methods

A cross-sectional self-administered survey was disseminated to collect responses from different Arab countries. Descriptive statistics were calculated for demographics. Data normality was assessed using Shapiro-Wilk test. Associations between sociodemographic variables and knowledge, attitudes and practices were explored using simple and multiple linear regression. Significance level was considered at p < 0.05.

Results

A total of 1,445 responses were collected. Mean (±SD) knowledge scores were low 8.61 ± 5.9. Eighty seven percent recognized magnesium role in alleviating muscle spasm and sleep disorders (83%). Magnesium citrate was the mostly used magnesium salt (37.43%). Neutral attitudes were observed with a mean score of 3.02 ± 0.66. Only 31.8% reported using magnesium supplements, 36.1% of them received a medical consultation. Having poly cystic ovary (p = 0.033), relying on scientific articles (0.004), receiving pharmacist consultation (p = 0.019) significantly associated with higher knowledge.

Conclusion

Despite the huge debate regarding magnesium benefits in maintaining muscle, bone health and improving sleep quality, this study found that there is a significant gap in knowledge and neutral attitude towards magnesium supplementation in Arab communities. These findings emphasizes the need for educational campaigns targeting the public on the rationale use of supplements.

Supplemental magnesium gluconate recovers osteoblastic Wntless ablation-induced degenerative bone complications

INTRODUCTION

Although numerous studies have highlighted the involvement of Wnt-mediated signaling in Mg ion-enhanced bone healing, whether Wnt-stimulated signaling is essential for the Mg ion-triggered bone repair and mass accrual is not yet completely understood.

MATERIALS AND METHODS

We generated Wlsfl/fl wild-type (WT) control and their corresponding mutant (MT), Col2.3-Cre;Wlsfl/fl mice of osteoblastic Wntless (Wls) ablation and explored how supplemental magnesium gluconate (MgG) affects bone mass accrual and defected bone healing in relation to the Wls ablation.

RESULTS

Osteoblastic Wls ablation impaired bone mass accrual and bone healing along with age-related degenerative complications in bone marrow (BM) and BM cells. Oral supplementation of WT mice with MgG did not change natural bone mass accrual, but enhanced regenerative bone healing in femoral defects and the functionalities of BM cells. Supplemental MgG suppressed the Wls ablation-related bone loss and also stimulated new bone formation in the defects of MT mice. The MgG-induced beneficial effects in the MT mice were orchestrated with its potencies to ameliorate senescence, oxidative damage, and functional loss of BM and BM adherent cells, as well as to stimulate osteogenic activity.

CONCLUSION

This study demonstrates that supplemental MgG is able to improve bone homeostatic maintenance by recovering age-related degenerative complications even at the lack of osteoblastic Wnt-stimulated signaling.

Determination of Essential Minerals in the Indigenous Vegetables Solanum nigrum (Stout Shade) and Gynandropsis gynandra (Spider Plant) from Two Agroecological Zones in Kisii County, Kenya

Vegetables are good sources of essential mineral elements that promote good health and immunity. Information on the nutritional contents of indigenous vegetables is scarce. Therefore, this study sought to ascertain the concentrations of magnesium, manganese, chrome, zinc, copper, and iron in Solanum nigrum and Gynandropsis gynandra indigenous vegetables from two agroecological zones (upper midland and lower highland) of Kisii County, Kenya, using inductively coupled plasma optical emission spectroscopy (ICP‒OES). For Gnandropsis gynandra, the most abundant erythrocytic synthesis element was Fe (1856.67 ± 15.28 mg/kg DW) for plants harvested from Nyanchwa (UM), and the least was Cu (8.90 ± 0.44 mg/kg DW) in plants harvested from Kari (LH). In addition, Mg was the hypoglycemic element with the highest concentration (5975.00 ± 10.00 mg/kg DW), and Cr lowest (3.16 ± 0.45 mg/kg DW) in samples harvested from Matongo (UM). For Solanum nigrum, the most erythrocytic synthesis element was Fe (1280.00 ± 10.00 mg/kg DW for samples collected from Kiamabundu (UM), and the least was Cu (9.08 ± 0.15 mg/kg DW) in the samples from Nyanchwa (UM), whereas Mg in samples from Nyabioto (UM) was the hypoglycemic element with the highest concentration (4920.00 ± 10.00 mg/kg DW) and Cr in samples from Mariba (LH had the lowest concentration) (3.95 ± 1.63 mg/kg DW). The concentrations of elements in the two indigenous vegetables from the UM agroecological zone were slightly greater than those in the LH agroecological zone. Nonetheless, the variations observed were not statistically significant (P < 0.05). Enzymatically bio accessed concentrations of iron, zinc, chromium, magnesium, manganese, and copper were higher than those obtained aquatically. The indigenous vegetable bio avails substantial amounts of iron and copper to enable them be used in the management pernicious anaemia; on the other hand, the substantial bio availed levels of zinc, manganese, magnesium, and chromium enables the vegetable to be used in the management of diabetes.

Degradation products of magnesium implant synergistically enhance bone regeneration: Unraveling the roles of hydrogen gas and alkaline environment

Biodegradable magnesium (Mg) implant generally provides temporary fracture fixation and facilitates bone regeneration. However, the exact effects of generated Mg ions (Mg2+), hydrogen gas (H2), and hydroxide ions (OH-) by Mg degradation on enhancing fracture healing are not fully understood. Here we investigate the in vivo degradation of Mg intramedullary nail (Mg-IMN), revealing the generation of these degradation products around the fracture site during early stages. Bulk-RNA seq indicates that H2 and alkaline pH increase periosteal cell proliferation, while Mg2+ may mainly enhance extracellular matrix formation and cell adhesion in the femur ex vivo. In vivo studies further reveal that H2, Mg2+ and alkaline pH individually generate comparable effects to the enhanced bone regeneration in the Mg-IMN group. Mechanistically, the degradation products elevate sensory calcitonin gene-related peptide (CGRP) and simultaneously suppress adrenergic factors in newly formed bone. H2 and Mg2+, instead of alkaline pH, increase CGRP synthesis and inhibit adrenergic receptors. Our findings, for the first time, elucidate that Mg2+, H2, and alkaline pH environment generated by Mg-IMN act distinctly and synergistically mediated by the skeletal interoceptive regulation to accelerate bone regeneration. These findings may advance the understanding on biological functions of Mg-IMN in fracture repair and even other bone disorders.

Mo and Sn exposure associated with the increased of bone mineral density

Bone mineral density (BMD) measured by T-score is strongly associated with bone health, but research on its association with metals in humans body remains limited. To investigate the relationship between metal exposure and BMD, numbers of 159 participants in eastern China were studied. Urine and blood samples were collected and levels of 20 metals in the samples were measured using Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). Binary Logistic Regression model (BLR) and Generalized Linear Models (GLM) were used to explore the relationship between metals and BMD. Bayesian Kernel Machine Regression (BKMR) model was further used to explore the effect of multiple metal interactions on BMD. Six metals (Mn, Co, As, Se, Mo, Cd) were selected and the concentrations in blood and urine were compared using Wilcoxon and Spearman tests. In the single-metal model, BLR and GLM commonly showed positive significant correlations between four metals (As, Mo, Se, Sn) in urine and BMD. Strong correlations between five metals (Mn, Co, As, Se, Mo) in blood and urine were observed (P ≤ 0.05). The BKMR model indicated a predominant synergistic effect of urine Mo and Sn, increased co-exposure to these metals is associated with a higher trend of BMD. These findings suggest that exposure to metals is associated with an increased level of BMD in humans. To better understand the impact of metals on bone health, further investigation into the common roles of these metals and their interactions is needed.

The essential role of magnesium in immunity and gut health: Impacts of dietary magnesium restriction on peritoneal cells and intestinal microbiome

Magnesium (Mg2+) is essential for life, and low levels impair immune function, promote chronic inflammation, and influence the intestinal microbiome, with the peritoneal cavity serving as a site for direct interaction between the cavity and intestinal contents, including the microbiota. This study investigates the effects of a Mg2+-restricted diet on peritoneal immune cells and its interplay with the intestinal microbiome. Male C57BL/6NTaq mice were divided into three groups: control, restricted, and restored. The control group received a diet containing 500 mg Mg2+/kg, the restricted group received a diet with 50 mg Mg2+/kg for four weeks, and the restored group first received the restricted diet for four weeks, followed by the control diet supplemented with 0.5 g MgCl₂ per liter of water for an additional four weeks. Results showed Mg2+ restriction did not affect body weight, food intake, or water consumption but induced hypomagnesemia, reversible upon dietary restoration. Mg2+ deficiency increased in neutrophils numbers in the blood and peritoneal cavity, indicating an inflammatory response. Gene expression analysis in peritoneal mononuclear cells revealed elevated levels of Nfkb, Stat1 and Stat3, suggesting heightened inflammatory signaling. Additionally, cytokine expression analysis showed increased levels of Tnfa, Il1b and Il10, but not Il6, in Mg2+-restricted group. The intestinal microbiome of Mg2+-restricted mice exhibited increased alpha diversity, with changes in taxa abundance, including an increase in Romboutsia ilealis and a decrease in the Oscillospiraceae and Lachnospiraceae. Mg2+ deficiency significantly affects some immune functions and gut microbiota, highlighting the importance of Mg²+ in maintaining the gut health.

Analyses of Antioxidant Properties, Mineral Composition, and Fatty Acid Profiles of Soy-Based Beverages Before and After an In Vitro Digestion Process

Soy beverages (SB) are the most popular beverage in the expanding market of plant-based drinks. They provide high-quality protein and polyphenols and are often Ca-fortified as a milk alternative. This work evaluated the antioxidant potential, the mineral content, and the fatty acid profiles found in SB, analysing as well the bioaccessibility of some nutrients after INFOGEST static digestion. Five types of SB available in the market, including Ca-fortified, high-protein, and low-fat drinks, were analysed. Ca supplementation and high protein content in the beverages significantly enhanced Ca bioaccessibility. The lipid profile demonstrated substantial changes during digestion, due to drastic reductions in saturated fatty acids and marked increases in polyunsaturated fatty acids in the bioaccessible fractions; these changes were mainly related to the content levels of Ca and polyphenols in the beverages. Significant increases in the antioxidant properties, as measured by ABTS and FRAP assays, were noticed after the digestive process. Additionally, ROS generation in Caco-2 cells after induced oxidative damage was prevented by the BF of digested SB. The digested low-fat drink, which also had a low level of protein content, showed the least antioxidant activity. In conclusion, composition of the soy drink considerably affected the bioaccessibility of nutritional components and the drink's antioxidant potential.

Nutritional Support of Chronic Obstructive Pulmonary Disease

Background: COPD is a heterogenous disease of the respiratory tract caused by diverse genetic factors along with environmental and lifestyle-related effects such as industrial dust inhalation and, most frequently, cigarette smoking. These factors lead to airflow obstruction and chronic respiratory symptoms. Additionally, the increased risk of infections exacerbates airway inflammation in COPD patients. As a consequence of the complex pathomechanisms and difficulty in treatment, COPD is among the leading causes of mortality both in the western countries and in the developing world. Results: The management of COPD is still a challenge for the clinicians; however, alternative interventions such as smoking cessation and lifestyle changes from a sedentary life to moderate physical activity with special attention to the diet may ameliorate patients' health. Here, we reviewed the effects of different dietary components and supplements on the conditions of COPD. Conclusions: COPD patients are continuously exposed to heavy metals, which are commonly present in cigarette smoke and polluted air. Meanwhile, they often experience significant nutrient deficiencies, which affect the detoxification of these toxic metals. This in turn can further disrupt nutritional balance by interfering with the absorption, metabolism, and utilization of essential micronutrients. Therefore, awareness and deliberate efforts should be made to check levels of micronutrients, with special attention to ensuring adequate levels of antioxidants, vitamin D, vitamin K2, magnesium, and iron, as these may be particularly important in reducing the risk of COPD development and limiting disease severity.

Complex Analysis of Micronutrient Levels and Bone Mineral Density in Patients with Different Types of Osteogenesis Imperfecta

Background: Osteogenesis imperfecta (OI) is a rare monogenic connective tissue disorder characterized by fragility of bones and recurrent fractures. In addition to the hereditary component, there are a number of factors that influence the course of the disease, the contribution of which is poorly understood, in particular the levels of micronutrients. Methods: A cross-sectional study was conducted involving 45 with OI and 45 healthy individuals. The concentrations of micronutrients (calcium, copper, inorganic phosphorus, zinc, and magnesium) and bone mineral density (BMD) were evaluated in all the participants. Results: The concentrations of micronutrients in all the groups were within the reference values. In the OI overall, magnesium and copper were elevated, and phosphorus and zinc were lower. Type I exhibited higher concentrations of magnesium and copper and the lowest phosphorus; type III was associated with lower zinc, type IV with lower calcium and higher copper, and type V with the lowest phosphorus. OI overall was associated with lower BMD values. A correlational analysis in the OI group showed that the number of fractures correlated with BMD in absolute values but not with the Z-score. Conclusions: The obtained data emphasize the importance of the levels of micronutrients in the pathogenesis of connective tissue diseases, in particular OI. As in the results of previous studies, the levels of micronutrients were within the population norm, which probably requires the development of individual criteria for the content of substances in this category of patients.

Enhanced bone cement for fixation of prosthetic joint utilizing nanoparticles

Bone cement is commonly utilized to secure prosthetic joints in the body because of its robust fixation, stability, biocompatibility, and immediate load-bearing capability. However, issues such as loosening, leakage, and insufficient bioactivity can lead to its failure. Therefore, improving its mechanical, physical, and biological properties is crucial for enhancing its efficiency. This study examines the impact of incorporating four different nanomaterials-Titanium Dioxide (TiO2), Magnesium Oxide (MgO), Calcium Phosphate (Ca3(PO4)2), and Alumina Oxide (Al2O3)-into bone cement on its mechanical, physical, and biological properties. TiO2 and Al2O3 nanoparticles are selected to enhance the compression strength of bone cement, thereby preventing loosening. Magnesium Oxide (MgO) and Ca3(PO4)2 nanoparticles are chosen to improve cell adhesion and reducing the risk of cement leakage. Five specimens were prepared: the first with 100% pure bone cement powder, the second with 98% pure bone cement powder and modified with 2% MgO and TiO2, and the remaining three with 95% pure bone cement powder and modified with 5% varying ratios of MgO, TiO2, Ca3(PO4)2, and Al2O3. Compression, tensile, hardness, and bending strengths were assessed to determine improvements in mechanical properties. Setting temperature, porosity, and degradation were measured to evaluate physical properties. Cell adhesion and toxicity tests were conducted to examine the surface structure and biological properties. The results demonstrated that the modified specimens increased compression strength by 8.14%, tensile strength by 3.4%, and bending strength by 4.96%. Porosity, degradation, and setting temperature in modified specimens increased by 3.24%, 0.64%, and 5.17% respectively pure bone cement values. Cell adhesion in modified bone cement specimens showed normal attachment when scanned with FE-SEM. All of the tested modified specimens showed no toxicity, except for specimens with 2% Al2O3 that showed 25% toxicity which could be averted by employing antibiotics.

Decrease in Facial Bone Density with Aging and Maintenance Effect of Calcium Maltobionate Ingestion in Japanese Adult Women: A Randomized, Double-Blind, Placebo-Controlled, Parallel-Group Trial

BACKGROUND/OBJECTIVES

Facial bone density, including the jawbone, declines earlier than that of the lumbar spine and calcaneus. Calcium maltobionate is reported to mitigate bone resorption and maintain bone density of the lumbar spine in post-menopausal women, but its effects on facial bone density remain understudied. Therefore, this study compared variations in facial bone mineral density with variations in calcaneal bone mineral density and bone resorption markers among healthy women, examining differences between pre- and post-menopause and the effects of continuous calcium maltobionate intake.

METHODS

This randomized, double-blind, placebo-controlled, parallel-group trial involved 48 healthy Japanese women aged 30-69 years, divided into two groups. The test food group received tablets containing calcium maltobionate, while the placebo group received tablets containing a maltose and calcium carbonate mixture for 24 weeks. Calcaneal and facial bone densities were measured pre- and post-intervention in both groups.

RESULTS

Post-intervention calcaneal bone mineral density and bone resorption marker deoxypyridinoline (DPD) showed no statistical difference between groups in pre-menopausal women. However, in post-menopausal women, the test food group exhibited significantly higher calcaneal bone density and lower DPD levels compared with the placebo group. Facial bone mineral density increased significantly in the test food group compared with the placebo group in post-menopausal participants, with similar trends observed in pre-menopausal participants.

CONCLUSIONS

Facial bone mineral density could serve as a useful indicator for monitoring bone health from middle age onward. Moreover, continuous calcium maltobionate intake appears to mitigate bone density decline in pre- and post-menopausal women, contributing to osteoporosis prevention (UMIN-CTR ID: 000046391).

Supplemental Magnesium Gluconate Enhances Scaffold-Mediated New Bone Formation and Natural Bone Healing by Angiogenic- and Wnt Signal-Associated Osteogenic Activation

Local implantation or supplementation of magnesium gluconate (MgG) is being investigated as an effective approach to bone repair. Although studies have highlighted the possible mechanisms in Mg ion-stimulated new bone formation, the role of MgG in healing bone defects and the signaling mechanisms are not yet completely understood. In this study, we explored how supplemental MgG has bone-specific beneficial effects by delivering MgG locally and orally in animal models. We fabricated MgG-incorporated (CMC-M) and -free chitosan (CMC) scaffolds with good microstructures and biocompatible properties. Implantation with CMC-M enhanced bone healing in rat model of mandible defects, compared with CMC, by activating Wnt signals and Wnt-related osteogenic and angiogenic molecules. Oral supplementation with MgG also stimulated bone healing in mouse model of femoral defects along with the increases in Wnt3a and angiogenic and osteogenic factors. Supplemental MgG did not alter nature bone accrual and bone marrow (BM) microenvironment in adult mouse model, but enhanced the functioning of BM stromal cells (BMSCs). Furthermore, MgG directly stimulated the induction of Wnt signaling-, angiogenesis-, and osteogenesis-related molecules in cultures of BMSCs, as well as triggered the migration of endothelial cells. These results suggest that supplemental MgG improves bone repair in a way that is synergistically enhanced by Wnt signal-associated angiogenic and osteogenic molecules. Overall, this study indicates that supplemental MgG might ameliorate oxidative damage in the BM, improve the functionality of BM stem cells, and maintain BM-microenvironmental homeostasis.

Magnesium-Impregnated Membrane Promotes Bone Regeneration in Rat Skull Defect by N-Linked Glycosylation of SPARC via MagT1

Autograft has long been the gold standard for various bone surgeries. Nevertheless, the increasing usage of synthetic implants is taking over the operation rooms due to biosafety and standardized protocols. To fulfill such tremendous needs, a magnesium-impregnated membrane is devised that steadily releases magnesium ions to stimulate osteogenesis. The compatibility of Magnesium oxide (MgO) particles is enhanced through hydration and grafting, characterized by scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). With detailed degradation profiles, an in-depth investigation of Magnesium transporter 1 (MagT1) for magnesium intake is carried out and engaging in the N-linked glycosylation by using RNAi and inhibitors. The glycosylation of secreted protein acidic and rich in cysteine (SPARC) affected extracellular secretion and mineral deposition, demonstrated by immunostaining and density-dependent color-SEM (DDC-SEM). Skull defects are treated by implanting magnesium-impregnated membranes in rats and evaluated them by micro-CT and histological exams. This study revealed the compatible integration of grafted magnesium hydroxide (g-MH) particles is the key to functional performance and critical to applicability in vivo; meanwhile, it opens the door to a biological rationale for designing biomimetic materials.

The Biological Effects of Magnesium-Based Implants on the Skeleton and Their Clinical Implications in Orthopedic Trauma Surgery

Magnesium (Mg)-based implants have evolved as a promising innovation in orthopedic trauma surgery, with the potential to revolutionize the treatment of bone diseases, including osteoporotic fractures and bone defects. Available clinical studies mostly show excellent patient outcomes of resorbable Mg-based implants, without the need for subsequent implant removal. However, the occurrence of radiolucent zones around Mg-based implants seems to be a noticeable drawback for a more widespread clinical use. Mechanistically, both in vivo and in vitro studies demonstrated beneficial effects on the formation of new bone, a unique characteristic of Mg-based implants. In this regard, Mg has been shown to exert pleiotropic functions on osteogenic differentiation and migration of osteoblasts and their precursors. Additionally, collective evidence suggests that Mg-based implants promote angiogenesis in newly formed bone and exert immunomodulatory effects in the bone microenvironment. Likewise, Mg-based implants and their degradation products were shown to inhibit bone resorption by impairing osteoclastogenesis. The purpose of this review is to provide a state-of-the-art summary of the clinical and basic science evidence regarding the performance of currently used Mg-based implants. In addition to the status of in vivo and in vitro research and clinical applications, future challenges and perspectives of Mg-based orthopedic implants are discussed.

The Role of Inflammatory and Nutritional Indices in Postmenopausal Osteoporosis: A Retrospective Study

Background: Postmenopausal osteoporosis is characterized by impaired bone metabolism, inflammation, and nutritional deficiencies. This study aimed to evaluate the potential of inflammatory and nutritional markers in identifying decreased bone mineral density (BMD) in postmenopausal women. Methods: This cross-sectional study retrospectively analyzed postmenopausal women from January 2018 and December 2023. A total of 368 women were divided into three groups based on T-scores: 61 women with osteoporosis (T-score ≤ -2.5), 153 women with osteopenia (-1 > T-score > -2.5), and 154 women with normal BMD (T-score > -1). Inflammatory and nutritional biomarkers included the neutrophil/lymphocyte ratio (NLR), platelet/lymphocyte ratio (PLR), monocyte/lymphocyte ratio (MLR), systemic immune-inflammation index (SII), systemic inflammation response index (SIRI), pan-immune inflammation value (PIV), geriatric nutritional risk index (GNRI), triglycerides, total cholesterol, and body weight index (TCBI), prognosis nutritional index (PNI), hemoglobin, albumin, lymphocyte, and platelet (HALP) score, 25-OH Vitamin D level, Na, K, Ca, Mg, and their ratios. Results: The GNRI was significantly lower in the osteoporosis group compared to the control group. The NLR, PLR, SII, SIRI, PIV, TCBI, PNI, and HALP were similar between the groups. The GNRI and TCBI showed a positive correlation with T-scores. The Mg level was lower in the osteoporosis group than in the control group and osteopenia group, and the Na/Mg ratio was higher. Additionally, the Ca/Mg ratio was lower in the osteoporosis group than in the control group. The T-score was positively correlated with Mg and Ca/Mg, while the Na/Mg ratio showed a significant negative correlation. Vitamin D, other minerals, and their ratios did not show significant differences between the groups. Conclusions: Our findings suggest that the GNRI could serve as a useful indicator for assessing bone health and the risk of osteoporosis. Furthermore, maintaining appropriate levels of Mg and balanced Na/Mg and Ca/Mg ratios appears crucial for BMD.

Magnesium-Based Composite Calcium Phosphate Cement Promotes Osteogenesis and Angiogenesis for Minipig Vertebral Defect Regeneration

Calcium phosphate cement (CPC) is an injectable bone cement with excellent biocompatibility, widely used for filling bone defects of various shapes. However, its slow degradation, insufficient mechanical strength, and poor osteoinductivity limit its further clinical applications. In this study, we developed a novel composite magnesium-based calcium phosphate cement by integrating magnesium microspheres into PLGA fibers obtained through wet spinning and incorporating these fibers into CPC. The inclusion of magnesium-based PLGA fibers enhanced the compressive strength and degradation rate of CPC, with the degradation rate of the magnesium microspheres being controllable to allow for the sustained release of magnesium ions. In vitro experiments showed that magnesium-based CPC enhanced the proliferation and migration of MC3T3-E1 and HUVECs. Additionally, the magnesium-based composite CPC not only enhanced osteogenic differentiation of MC3T3-E1 cells but also promoted angiogenesis in HUVECs. In vivo experiments using a vertebral bone defect model in Bama miniature pigs showed that the magnesium-based composite CPC significantly increased new bone formation. Additionally, compared to the CPC group, this composite exhibited significantly higher levels of osteogenic and angiogenic markers, with no inflammation or necrosis observed in the heart, liver, or kidneys, indicating good biocompatibility. These results suggest that magnesium-based composite CPC, with its superior compressive strength, biodegradability, and ability to promote vascularized bone regeneration, holds promise as a minimally invasive injectable material for bone regeneration.

Magnesium Membrane Shield Technique for Alveolar Ridge Preservation: Step-by-Step Representative Case Report of Buccal Bone Wall Dehiscence with Clinical and Histological Evaluations

BACKGROUND/OBJECTIVES

Despite the increased use of new resorbable magnesium membranes, there are no reported cases or studies on the use of resorbable magnesium membranes in combination with bone grafts for alveolar ridge preservation (ARP) in cases with severe buccal bone wall dehiscence. This case report aimed to evaluate the effectiveness of the magnesium membrane shield technique in conjunction with bone grafting for ARP, assessing both clinical outcomes and histological bone regeneration.

METHODS

A 44-year-old female patient presented with a vertical fracture on tooth 24 (FDI Notation System) accompanied with complete destruction of the buccal bone wall. The treatment plan included tooth extraction, ARP using a combination of anorganic bovine bone and autologous bone grafting, and the application of a magnesium membrane as a shield to the pre-existing buccal wall. Six months post-procedure, a bone biopsy was taken from the implant site using a trephine bur.

RESULTS

Clinical and radiological evaluations six months after the procedure demonstrated sufficient bone volume for implant placement. Additionally, in the next three months, soft tissue conditioning with a provisional crown resulted in an aesthetically and functionally satisfactory outcome. Histological analysis of the bone biopsy revealed well-formed new bone in direct contact with residual biomaterial, with no signs of inflammation. Osteocytes were clearly visible within the newly formed bone matrix, indicating successful bone maturation. Active osteoblasts were observed along the bone-biomaterial interface, suggesting ongoing bone remodeling and integration. Additionally, histomorphometric evaluation revealed 47% newly formed bone, 32% soft tissue, and 19% residual biomaterial.

CONCLUSIONS

This case demonstrates the potential of the magnesium shield technique as an ARP technique in cases with severe buccal wall dehiscence. The technique yielded satisfactory clinical outcomes and promoted successful bone regeneration, as confirmed by histological analysis.

Biocompatibility and osteogenic capacity of additively manufactured biodegradable porous WE43 scaffolds: An in vivo study in a canine model

Magnesium is the most promising absorbable metallic implant material for bone regeneration and alloy WE43 is already FDA approved for cardiovascular applications. This study investigates the cyto- and biocompatibility of novel additively manufactured (AM) porous WE43 scaffolds as well as their osteogenic potential and degradation characteristics in an orthotopic canine bone defect model. The cytocompatibility was demonstrated using modified ISO 10993-conform extract-based indirect and direct assays, respectively. Additionally, degradation rates of WE43 scaffolds were quantified in vitro prior to absorption tests in vivo. Complete blood cell counts, blood biomarker analyses, blood trace element analyses as well as multi-organ histopathology demonstrated excellent biocompatibility of porous y WE43 scaffolds for bone defect repair. Micro-CT analyses further showed a relatively higher absorption rate during the initial four weeks upon implantation (i.e., 36 % ± 19 %) than between four and 12 weeks (41 % ± 14 %), respectively. Of note, the porous WE43 implants were surrounded by newly formed bony tissue as early as four weeks after implantation when unmineralized trabecular ingrowth was detected. After 12 weeks, a substantial amount of mineralized bone was detected inside and around the gradually disappearing implants. This first study on AM porous WE43 implants in canine bone defects demonstrates the potential of this alloy for in vivo applications in humans. Our data further underscore the need to control initial bulk absorption kinetics through surface modifications.

Evaluation of Aluminum and Magnesium Absorption Following the Oral Administration of an Antacid Suspension Containing Magaldrate in Healthy Women Under Fed Conditions

INTRODUCTION

Antacids are commonly used during pregnancy, and they are approved for the relief of symptoms of gastroesophageal reflux disease (GERD) during pregnancy. However, there are no reports of the quantification of the absorption of aluminum and magnesium in the antacid magaldrate in women. The aim of this study was to quantify the rate and magnitude of absorption of aluminum and magnesium in magaldrate.

METHODS

An open-label, controlled, randomized, one-treatment study with a two-group design was conducted in healthy women in a fed state. The volunteers had a standard breakfast, and 30 min later, they were given a single-medication sachet containing 500 mg of sodium alginate, 267 mg of sodium bicarbonate, 800 mg of magaldrate, and 120 mg of simethicone (group A, n = 8) or no medication (group B, n = 2). Blood samples were obtained 36 h before and up to 12 h after antacid administration. The method used for quantification was inductively coupled plasma-mass spectrometry.

RESULTS

There was no absorption of aluminum in any of the blood samples from the healthy volunteers who received the drug or in those from the control group. Magnesium was detected at normal concentrations.

CONCLUSION

These findings suggest that the use of this antacid is safe and without risk in healthy women, including pregnant women.

CLINICAL TRIAL REGISTRATION

Clinicaltrials.gov registration: NCT06367452.

Enhancing osteogenesis and mandibular defect repair with magnesium-modified acellular bovine bone matrix

An acellular bovine bone matrix modified to release Magnesium ions (Mg2+) (ABBM-Mg) was prepared and evaluated for its potential in osteogenesis and mandibular defect repair. Mg2+ was incorporated into ABBM using an ion exchange method. The microstructure and mechanical properties of both ABBM and ABBM-Mg were analyzed using SEM and a biomechanical testing machine. Cytocompatibility, cell adhesion, and osteogenic differentiation were assessed using various methods including CCK-8, Live/Dead staining, SEM, ALP staining, and qPCR analysis in MC3T3-E1 cells. Additionally, a mandibular defect model in rats was established. The bone defect repair outcomes were evaluated using Micro-CT, histological HE staining, and Masson staining. The study showed that mineralization containing magnesium was redeposited on the surface of the three-dimensional porous ABBM, and the ABBM-Mg scaffold promoted cell proliferation and osteogenic differentiation compared to the ABBM scaffold. In the rat mandibular defect model, the ABBM-Mg scaffold demonstrated superior bone repair ability. This study successfully incorporated Mg2+ into ABBM without significantly affecting its microstructure and compressive strength. Furthermore, ABBM-Mg showed sustained release of Mg2+ which enhanced cell proliferation, adhesion, and osteogenic differentiation in vitro, and promoted mandibular defect healing in rats. This research opens up new possibilities for the clinical application of functionalized acellular bone matrix.

Association between magnesium depletion score and periodontitis in US adults: results from NHANES 2009-2014

BACKGROUND

This study aims to explore the relationship between magnesium depletion score (MDS) and periodontitis in US adults using data from the National Health and Nutritional Examination Survey (NHANES) 2009-2014.

METHODS

This cross-sectional study's outcome was periodontitis, defined by the CDC/AAP using clinical periodontal parameters. The exposure of this study was MDS, which was calculated according to four parameters (diuretic use, proton pump inhibitor use, renal function and alcohol consumption). Weighted univariable and multivariable logistic regression analyses were performed to explore the association between MDS intake and periodontitis. Confounding factors included in the adjusted model were age, sex, race, income, smoking status, dietary magnesium, obesity, diabetes, hypertension, education level, recreational activity, and work activity.

RESULTS

A total of 8,628 participants over the age 30 were included in our study. Individuals with high level of magnesium deficiency were more likely referred to poorer periodontal health in both crude model (OR = 2.01, 95% CI: 1.54-2.61, p < 0.0001) and fully adjusted model (OR = 1.35, 95% CI: 1.03-1.77, p = 0.03).

CONCLUSIONS

MDS is positively associated with moderate/severe periodontitis. Further longitudinal studies are needed to understand the impact of MDS on periodontitis.

Nutraceuticals in osteoporosis prevention

Nutraceuticals are gaining popularity as they can contribute to bone health by delaying the onset or slowing down the progression of pathological bone loss. Osteoporosis's bone loss is a concern for older adults and a crucial aspect of aging. Maintaining healthy bones is the key to living a full and active life. Our review explores the current knowledge on the role of nutraceuticals in preventing osteoporosis by focusing on three main aspects. First, we provide an overview of osteoporosis. Second, we discuss the latest findings on natural nutraceuticals and their efficacy in reducing bone loss, emphasizing clinical trials. Third, we conduct a structured analysis to evaluate nutraceuticals' pros and cons and identify translational gaps. In conclusion, we must address several challenges to consolidate our knowledge, better support clinicians in their prescriptions, and provide people with more reliable nutritional recommendations to help them lead healthier lives.

Magnesium Matters: A Comprehensive Review of Its Vital Role in Health and Diseases

Magnesium (Mg), an essential mineral abundantly present within the human body, is intricately involved in a multitude of biochemical processes vital for maintaining health and overall well-being. This review aims to delve into the multifaceted impact of Mg on human health, exploring its physiological functions, dietary sources, and potential health implications of deficiency or insufficiency. Mg plays a pivotal role in various physiological processes, including energy metabolism, muscle contraction, protein synthesis, and DNA synthesis. It acts as a cofactor for more than 300 enzymatic reactions, facilitating the conversion of adenosine triphosphate (ATP) to adenosine diphosphate (ADP) for energy production. Moreover, Mg is essential for the proper functioning of ion channels, particularly calcium channels, influencing nerve transmission and muscle relaxation. Mg is naturally found in a wide array of foods, with green leafy vegetables, whole grains, nuts, seeds, and legumes being particularly rich sources. Additionally, certain fortified foods and dietary supplements provide supplemental Mg intake. Deficiency or insufficiency of mg can have profound implications for health. Inadequate mg levels have been associated with increased risks of various chronic diseases, including hypertension, type 2 diabetes, osteoporosis, and cardiovascular diseases. Furthermore, mg deficiency may manifest as symptoms such as muscle weakness, fatigue, tremors, and irregular heartbeat. Numerous studies have elucidated the relationship between mg intake and the risk of developing chronic diseases. For instance, epidemiological evidence suggests that higher mg intake is associated with a reduced risk of hypertension, possibly due to its vasodilatory effects and influence on blood pressure regulation mechanisms. Similarly, mg has been implicated in the pathophysiology of type 2 diabetes, with mg deficiency contributing to insulin resistance and impaired glucose metabolism. Furthermore, adequate mg intake is crucial for maintaining bone density and reducing the risk of osteoporosis, as mg plays a vital role in bone mineralization and bone health. Understanding the importance of mg in human physiology underscores the significance of ensuring adequate mg intake through diet or supplementation. Healthcare professionals play a critical role in educating individuals about the importance of incorporating mg-rich foods into their diets and considering mg supplementation when necessary, particularly for individuals at risk of deficiency or those with chronic diseases. Mg is an indispensable mineral with far-reaching implications for human health. Its involvement in various physiological processes underscores its importance in maintaining overall health and well-being. Ensuring adequate mg intake is essential for preventing deficiency-related health complications and reducing the risk of chronic diseases. Further research is warranted to elucidate the optimal strategies for mg supplementation and its potential therapeutic applications in disease prevention and management.

Development and evaluation of an injectable ChitHCl-MgSO4-DDA hydrogel for bone regeneration: In vitro and in vivo studies on cell migration and osteogenesis enhancement

Nonunion and delayed union of the bone are situations in orthopedic surgery that can occur even if the bone alignment is correct and there is sufficient mechanical stability. Surgeons usually apply artificial bone grafts in bone fracture gaps or in bone defect sites for osteogenesis to improve bone healing; however, these bone graft materials have no osteoinductive or osteogenic properties, and fit the morphology of the fracture gap with difficulty. In this study, we developed an injectable chitosan-based hydrogel with MgSO4 and dextran oxidative, with the purpose to improve bone healing through introducing an engineered chitosan-based hydrogel. The developed hydrogel can gelate and fit with any morphology or shape, has good biocompatibility, can enhance the cell-migration capacity, and can improve extracellular calcium deposition. Moreover, the amount of new bone formed by injecting the hydrogel in the bone tunnel was assessed by an in vivo test. We believe this injectable chitosan-based hydrogel has great potential for application in the orthopedic field to improve fracture gap healing.

Is there an Association between Dietary Micronutrients Intake and Bone Fractures among Malaysian Reproductive-Age Women? The PURE Malaysia Study

Background: Bone fractures represent a significant health issue and impose a considerable burden on healthcare systems globally. However, data pertaining to bone fractures, especially among reproductive-age women in Malaysia, are very limited. Micronutrients like calcium, magnesium and phosphorus play vital roles in bone health, influencing bone mineral density and fracture risk. The objective of this study was to determine the prevalence of bone fractures among reproductive-age women and the association with dietary micronutrient intakes. Methods: In this cross-sectional study, a total of 1,730 participants of reproductive-age women from the Malaysia Prospective Urban and Rural Epidemiological (PURE) study were recruited. The participants' dietary intakes were assessed using a validated semi-quantitative food frequency questionnaire (FFQ). Selected micronutrients in the participants' diets were calculated using the Malaysian food composition and the US Department of Agriculture food composition databases. The association between micronutrient intakes, comorbidities and physical activity levels with bone fractures were evaluated to identify predictors of bone fractures among reproductive-age women. Results: The prevalence of bone fractures among Malaysian reproductive-age women was low (3.7%). The multiple logistic regression analysis showed that none of the micronutrients was associated with bone fractures. However, factors of diabetes and passive smoking in this study showed 2.6- and 4.0-times-higher odds of having bone fractures, respectively (AOR 2.580; 95% CI: 1.173-5.672) and (AOR 4.012; 95% CI: 2.265-7.107). Conclusions: It was found that the majority of women in this study were taking lower micronutrient intakes of calcium, magnesium, and vitamin K than the Malaysia recommended nutrient intakes (RNI). Although this study showed that a low micronutrient intake is not significantly associated with bone fractures, it is recommended that future studies focus on controlled trials or prospective data analyses to establish causal relationships and the optimal micronutrient requirements for maintaining strong and healthy bones in women of reproductive age.

Bone and vascular effects of magnesium supplements in CKD patients (the MagicalBone Pilot Study)

BACKGROUND AND OBJECTIVE

The progression of chronic kidney disease (CKD) involves the development of alterations in mineral metabolism that are closely related to cardiovascular outcomes and bone disease. Hypomagnesemia is associated with more rapid progression of CKD and other comorbidities. Our objective was to analyze in CKD patients stages 3-4 the impact of the administration of magnesium (Mg) carbonate on bone mineral density (BMD) and hemodynamic changes associated with by vascular calcification (VC).

MATERIAL AND METHODS

Patients with CKD stages 3-4 were randomized into controls (n=12) or intervention (n=7) group receiving 360mg of Mg carbonate daily during a 15-month period. Parameters related to mineral metabolism, BMD, VC, and pulse wave velocity (PWV) were evaluated.

RESULTS

Supplementation with Mg produced an increase in the urinary excretion of Mg while serum Mg levels remained stable and no episodes of hypermagnesemia were reported. In addition, no significant changes were found in the degree of VC assessed by Adragao index, however, both serum and urine Mg were significantly associated with a decrease in PWV, suggesting an increase in vascular compliance. Likewise, BMD did not change following treatment, but serum Mg significantly correlated with the levels of N-terminal propeptide of collagen alpha-1(I) chain (PINP), a marker of bone synthesis.

CONCLUSIONS

In sum, these results suggest a possible beneficial effect of Mg on vascular compliance with no detrimental effects on bone status. In addition, our results highlight the need to consider monitorization of urinary Mg status in CKD patients.

Association between dietary inflammatory index and all-cause mortality in patients with osteopenia or osteoporosis: A retrospective cohort study from the NHANES 2007-2018

Objective

Osteoporosis is an inflammatory disease that causes a large disease burden worldwide. Dietary inflammation index (DII), a comprehensive assessment index that reflects the pro-inflammatory/anti-inflammatory level of diet was related to multiple inflammatory diseases. This study aimed to explore the association between DII and all-cause mortality in patients with osteoporosis or osteopenia.

Methods

In this retrospective cohort study, data of patients aged ≥ 45 years diagnosed as osteopenia or osteoporosis and had complete dietary intake information were extracted from the National Health and Nutrition Examination Survey (NHANES 2007-2010, 2013-2014, 2017-2018). Dietary intake information was obtained from 24-h dietary recall interviews and was used to calculate the DII score. Weighted univariate and multivariate Cox proportional hazard models were utilized to explore the association between DII and all-cause mortality in patients with osteoporosis or osteopenia, with hazard ratios (HRs) and 95 % confidence intervals (CIs). Subgroup analyses based on different age, gender and complications were further assessed this association.

Results

A total of 5,381 patients were included. Until December 31, 2019, 1,286 all-cause deaths occurred. After adjusting all covariates, high DII was associated with the high odds of all-cause mortality among patients with osteoporosis or osteopenia (HR=1.28, 95 %CI: 1.10-1.48), especially in the male (HR=1.38, 95 %CI: 1.06-1.78), aged < 65 years (HR=1.49, 95 %CI: 1.09-2.02), and without the history the cardiovascular disease (HR=1.30, 95 %CI: 1.03-1.65), diabetes mellitus (HR=1.27, 95 %CI: 1.06-1.52) and chronic kidney disease (HR=1.28, 95 %CI: 1.03-1.58).

Conclusion

A pro-inflammatory diet may have an adverse effect on the prognosis of osteoporosis patients.

Metal ions in biomedically relevant macromolecular structures

Understanding the functions of metal ions in biological systems is crucial for many aspects of research, including deciphering their roles in diseases and potential therapeutic use. Structural information about the molecular or atomic details of these interactions, generated by methods like X-ray crystallography, cryo-electron microscopy, or nucleic magnetic resonance, frequently provides details that no other method can. As with any experimental method, they have inherent limitations that sometimes lead to an erroneous interpretation. This manuscript highlights different aspects of structural data available for metal-protein complexes. We examine the quality of modeling metal ion binding sites across different structure determination methods, where different kinds of errors stem from, and how they can impact correct interpretations and conclusions.

Optic disc drusen: Dystrophic calcification, a potential target for treatment

Optic disc drusen (ODD) are calcified, acellular bodies, seen in the optic nerve head of up to 2% of the population. Although seldomly affecting visual acuity, visual field defects are common, and severe, ischemic complications causing irreversible vision loss are known to occur. Different treatment strategies for ODD have been explored, but so far without success. This review focuses on the unique, calcified property of ODD, describing what we know about ODD pathogenesis and previously tried treatment strategies. In this context, we discuss current knowledge about calcium and pathological calcifications, including intracranial and ocular calcifications. We also explore some of the obstacles that must be addressed to develop a therapy centred on the concept of calcification, should calcification be identified as a pathogenic factor contributing to vision loss.

Diet affects inflammatory arthritis: a Mendelian randomization study of 30 dietary patterns causally associated with inflammatory arthritis

Background

The causal associations between dietary intake and the risk and severity of Inflammatory Arthritis (IA) are currently unknown.

Objective

In this study, we aimed to investigate the causal relationship between nine dietary categories (30 types of diet) and IA using Mendelian randomization (MR).

Methods

We analyzed data from 30 diets and IA in a genome-wide association study (GWAS). Single nucleotide polymorphisms (SNPs) that could influence the results of MR analyses were screened out through the Mendelian Randomization Pleiotropy RESidual Sum and Outlier (MR-PRESSO) test. SNPs were analyzed through two-sample bidirectional MR using inverse variance weighting, MR-Egger regression, and weighted median method. The multiplicity and heterogeneity of SNPs were assessed using MR-Egger intercept term tests and Cochran's Q tests. FDR correction was used to correct the p-values.

Results

IVW results showed that Beef intake [Odds ratio (OR) = 2.862; 95% confidence interval (CI), 1.360-6.021, p = 0.006, p_fdr < 0.05] was positively associated with rheumatoid arthritis(RA); Dried fruit intake (OR = 0.522; 95% CI, 0.349-0.781, p = 0.002, p_fdr < 0.05), and Iron intake (OR = 0.864; 95%CI, 0.777-0.960, p = 0.007, p_fdr < 0.05) were negatively associated with RA, all of which were evidence of significance. Fresh fruit intake (OR = 2.528. 95% CI, 1.063-6.011, p = 0.036, p_fdr > 0.05) was positively associated with psoriatic arthritis (PsA); Cheese intake (OR = 0.579; 95% CI, 0.367-0.914, p = 0.019, p_fdr > 0.05) was negatively associated with PsA; both were suggestive evidence. Processed meat intake (OR = 0.238; 95% CI, 0.100-0.565, p = 0.001, p_fdr < 0.05) was negatively associated with reactive arthritis (ReA), a protective factor, and significant evidence. All exposure data passed the heterogeneity check (Cochrane's Q test p > 0.05) and no directional pleiotropy was detected. Leave-one-out analyses demonstrated the robustness of the causal relationship in the positive results.

Conclusion

Our study presents genetic evidence supporting a causal relationship between diet and an increased risk of IA. It also identifies a causal relationship between various dietary modalities and different types of IA. These findings have significant implications for the prevention and management of IA through dietary modifications.

Magnesium Oxide Reduces Anxiety-like Behavior in Mice by Inhibiting Sulfate-Reducing Bacteria

The gut microbiota-brain axis allows for bidirectional communication between the microbes in our gastrointestinal (GI) tract and the central nervous system. Psychological stress has been known to disrupt the gut microbiome (dysbiosis) leading to anxiety-like behavior. Pathogens administered into the gut have been reported to cause anxiety. Whether commensal bacteria affect the gut-brain axis is not well understood. In this study, we examined the impact of a commensal sulfate-reducing bacteria (SRB) and its metabolite, hydrogen sulfide (H2S), on anxiety-like behavior. We found that mice gavaged with SRB had increased anxiety-like behavior as measured by the open field test. We also tested the effects of magnesium oxide (MgO) on SRB growth both in vitro and in vivo using a water avoidance stress (WAS) model. We found that MgO inhibited SRB growth and H2S production in a dose-dependent fashion. Mice that underwent psychological stress using the WAS model were observed to have an overgrowth (bloom) of SRB (Deferribacterota) and increased anxiety-like behavior. However, WAS-induced overgrowth of SRB and anxiety-like behavioral effects were attenuated in animals fed a MgO-enriched diet. These findings supported a potential MgO-reversible relationship between WAS-induced SRB blooms and anxiety-like behavior.

Iron, copper, zinc and magnesium on rheumatoid arthritis: a two-sample Mendelian randomization study

This study aimed to elucidate the causal genetic relationships between iron, copper, zinc, magnesium, and rheumatoid arthritis (RA). A two-sample Mendelian randomization (MR) analysis was conducted using the "TwoSampleMR" and "MendelianRandomization" packages in R. The random-effects inverse variance-weighted (IVW) method was used as the primary approach. We performed sensitivity analyses to test the reliability of the results. The random-effects IVW analysis revealed that there was no genetic causal relationship between iron (P = 0.429, odds ratio [OR] 95% confidence interval [CI] = 0.919 [0.746-1.133]), copper (P = 0.313, OR 95% CI = 0.973 [0.921-1.027]), zinc (P = 0.633, OR 95% CI = 0.978 [0.891-1.073]), or magnesium (P = 0.218, OR 95% CI = 0.792 [0.546-1.148]) and RA. Sensitivity analysis verified the reliability of the results. Therefore, there is no evidence to support a causal relationship between iron, copper, zinc, and magnesium intake at the genetic level and the development of RA.

Changes in bone turnover markers 6-12 months after bariatric surgery

A rise in bone turnover markers (BTM) after bariatric surgery predicts poor bone health years later. This study explored factors associated with BTM and changes in BTM after bariatric surgery. Inclusion criteria were subjects 18 to 65 years of age with morbid obesity undergoing bariatric surgery. All data were measured before and 6 and 12 months after surgery. The study included 104 subjects: women/men: 83/21; mean age 43.1 (SD 8.4) years; BMI: 38.8 kg/m2 (SD 3.8). Surgery with Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG) was performed in 84 (81%) and 20 (19%) subjects, respectively. From before to 6-12 months after surgery, procollagen type 1 N-terminal propeptid (P1NP) increased by 45.6 µg/L (95% CI 41.5-50.0, p < 0.001), and alkaline phosphatase (ALP) by 10 U/L (95% CI 7-14, p < 0.001). The increases were significantly larger after RYGB than after SG. The APOE- Ɛ3 allele was associated with low levels of BTM and high levels of leptin. There was an unfavourable increase in BTM after bariatric surgery. SG compared to RYGB and the presence of the APOE-Ɛ3 allele were associated with less unfavourable effects. The study emphasises the importance of optimal prophylactic interventions after bariatric surgery to prevent osteoporosis.

Eggshell membrane as promising supplement to maintain bone health: A systematic review

Bone loss is a well-known phenomenon in the older population leading to increased bone fracture risk, morbidity, and mortality. Supplementation of eggshell membrane (ESM) is evaluated due to its possible application to prevent bone loss and usage in osteoporosis therapy. The similar organic chemical composition of ESM and human bone is described in detail as both mainly consist of collagen type I, chondroitin sulfate, dermatan sulfate, hyaluronic acid and elastan. ESM and its components are reported to improve mineralization in bone tissue. In many studies ESM intake reduced pain in patients with joint disorders and reduced inflammatory processes. Additionally, ESM improved calcium uptake in human cells. These findings in comparison with a clinical pilot study reporting pain reduction in osteoporotic patients and increased osteoblast activity in in vitro assays support ESM to be a beneficial supplement for bone health. In this systematic review we combined chemical structure analysis with clinical studies to give a more comprehensive picture with novel explanations.

Magnetic Resonance Imaging and Manganism: A Narrative Review and Laboratory Recommendations

In recent years, a series of articles has been published concerning magnetic resonance imaging (MRI) studies in a group of patients exposed to manganism, specifically factory workers, welders, and individuals with liver diseases, as well as those abusing home-produced ephedrone. Some potential symptoms of manganese toxicity include motor disturbances, neurocognitive problems, sleep disorders, and psychosocial changes. Despite various publications on MRI research in individuals with an elevated risk of manganism, there is a noticeable absence of a comprehensive review in this field. The detection of the accumulation of manganese in the brain through MRI can confirm the diagnosis and guide appropriate treatment. Due to the high cost of determining manganese ion levels in biological material, an additional aim of the manuscript was to identify simple medical laboratory parameters that, when performed concurrently with MRI, could assist in the diagnosis of manganism. Among these types of parameters are the levels of bilirubin, magnesium, liver enzymes, creatinine, hemoglobin, and hematocrit.

In Vivo Biocompatibility Study on Functional Nanostructures Containing Bioactive Glass and Plant Extracts for Implantology

In this paper, the in vivo behavior of orthopedic implants covered with thin films obtained by matrix-assisted pulsed laser evaporation and containing bioactive glass, a polymer, and natural plant extract was evaluated. In vivo testing was performed by carrying out a study on guinea pigs who had coated metallic screws inserted in them and also controls, following the regulations of European laws regarding the use of animals in scientific studies. After 26 weeks from implantation, the guinea pigs were subjected to X-ray analyses to observe the evolution of osteointegration over time; the guinea pigs' blood was collected for the detection of enzymatic activity and to measure values for urea, creatinine, blood glucose, alkaline phosphatase, pancreatic amylase, total protein, and glutamate pyruvate transaminase to see the extent to which the body was affected by the introduction of the implant. Moreover, a histopathological assessment of the following vital organs was carried out: heart, brain, liver, and spleen. We also assessed implanted bone with adjacent tissue. Our studies did not find significant variations in biochemical and histological results compared to the control group or significant adverse effects caused by the implant coating in terms of tissue compatibility, inflammatory reactions, and systemic effects.

Advances in magnesium-containing bioceramics for bone repair

Reconstruction of bone defects or fractures caused by ageing, trauma and tumour resection is still a great challenge in clinical treatment. Although autologous bone graft is considered as gold standard, the source of natural bone is limited. In recent years, regenerative therapy based on bioactive materials has been proposed for bone reconstruction. Specially, numerous studies have indicated that bioactive ceramics including silicate and phosphate bioceramics exhibit excellent osteoinductivity and osteoconductivity, further promote bone regeneration. In addition, magnesium (Mg) element, as an indispensable mineral element, plays a vital role in promoting bone mineralisation and formation. In this review, different types of Mg-containing bioceramics including Mg-containing calcium phosphate-based bioceramics (such as Mg-hydroxyapatite, Mg-biphasic calcium phosphate), Mg-containing calcium silicate-based bioceramics (such as Mg2SiO4, Ca2MgSi2O7 and Mg-doped bioglass), Mg-based biocements, Mg-containing metal/polymer-bioceramic composites were systematacially summarised. Additionally, the fabrication technologies and their materiobiological effects were deeply discussed. Clinical applications and perspectives of magnesium-containing bioceramics for bone repair are highlighted. Overall, Mg-containing bioceramics are regarded as regenerative therapy with their optimised performance. Furthermore, more in-depth two-way researches on their performance and structure are essential to satisfy their clinical needs.

Magnesium-containing bioceramics stimulate exosomal miR-196a-5p secretion to promote senescent osteogenesis through targeting Hoxa7/MAPK signaling axis

Stem cell senescence is characterized by progressive functional dysfunction and secretory phenotypic changes including decreased proliferation, dysfunction of osteogenic and angiogenic differentiation, increased secretion of the senescence-associated secretory phenotype (SASP), which bring difficulties for bone repair. Rescuing or delaying senescence of aged bone marrow mesenchymal stem cells (O-BMSCs) was considered as effective strategy for bone regeneration in aging microenvironment. Magnesium (Mg) ion released from bioceramics was reported to facilitate bone regeneration via enhancing osteogenesis and alleviating senescence. In this study, Akermanite biocreamics (Akt) containing Mg ion as a model was demonstrated to promote osteogenesis and angiogenesis effects of O-BMSCs by activating the MAPK signaling pathway in vitro. Moreover, the enhanced osteogenesis effects might be attributed to enhanced Mg-containing Akt-mediated exosomal miR-196a-5p cargo targeting Hoxa7 and activation of MAPK signaling pathway. Furthermore, the in vivo study confirmed that 3D-printed porous Mg-containing Akt scaffolds effectively increased bone regeneration in cranial defects of aged rats. The current results indicated that the exosomal-miR-196a-5p/Hoxa7/MAPK signaling axis might be the potential mechanism underlying Akt-mediated osteogenesis. The exosome-meditaed therapy stimulated by the released Mg ion contained in Akt biocreamics or other biomaterials might serve as a candidate strategy for bone repair in aged individuals.

Effect of using nano-particles of magnesium oxide and titanium dioxide to enhance physical and mechanical properties of hip joint bone cement

In this work, the effect of adding Magnesium Oxide (MgO) and Titanium Dioxide (TiO2) nanoparticles to enhance the properties of the bone cement used for hip prosthesis fixation. Related to previous work on enhanced bone cement properties utilizing MgO and TiO2, samples of composite bone cement were made using three different ratios (0.5%:1%, 1.5%:1.5%, and 1%:0.5%) w/w of MgO and TiO2 to determine the optimal enhancement ratio. Hardness, compression, and bending tests were calculated to check the mechanical properties of pure and composite bone cement. The surface structure was studied using Fourier transform infrared spectroscopy (FTIR) and Field emission scanning electron microscopy (FE-SEM). Setting temperature, porosity, and degradation were calculated for each specimen ratio to check values matched with the standard range of bone cement. The results demonstrate a slight decrease in porosity up to 2.2% and degradation up to 0.17% with NP-containing composites, as well as acceptable variations in FTIR and setting temperature. The compression strength increased by 2.8% and hardness strength increased by 1.89% on adding 0.5%w/w of MgO and 1.5%w/w TiO2 NPs. Bending strength increases by 0.35% on adding 1.5% w/w of MgO and 0.5% w/w TiO2 NPs, however, SEM scan shows remarkable improvement for surface structure.

Magnesium and Vascular Calcification in Chronic Kidney Disease: Current Insights

Magnesium (Mg) plays crucial roles in multiple essential biological processes. As the kidneys are the primary organ responsible for maintaining the blood concentration of Mg, people with chronic kidney disease (CKD) may develop disturbances in Mg. While both hyper- and hypomagnesemia may lead to adverse effects, the consequences associated with hypomagnesemia are often more severe and lasting. Importantly, observational studies have shown that CKD patients with hypomagnesemia have greater vascular calcification. Vascular calcification is accelerated and contributes to a high mortality rate in the CKD population. Both in vitro and animal studies have demonstrated that Mg protects against vascular calcification via several potential mechanisms, such as inhibiting the formation of both hydroxyapatite and pathogenic calciprotein particles as well as limiting osteogenic differentiation, a process in which vascular smooth muscle cells in the media layer of the arteries transform into bone-like cells. These preclinical findings have led to several important clinical trials that have investigated the effects of Mg supplementation on vascular calcification in people with CKD. Interestingly, two major clinical studies produced contradictory findings, resulting in a state of equipoise. This narrative review provides an overview of our current knowledge in the renal handling of Mg in health and CKD and the underlying mechanisms by which Mg may protect against vascular calcification. Lastly, we evaluate the strength of evidence from clinical studies on the efficacy of Mg supplementation and discuss future research directions.

Morphological and fractal features of cancer cells anchored on composite layers based on magnesium-doped hydroxyapatite loaded in chitosan matrix

In the present study, we report the development and characterization of composite layers (by spin coating) based on magnesium-doped hydroxyapatite in a chitosan matrix, containing human osteosarcoma MG63 cells anchored. Studies regarding the biocompatibility of the composite layers were performed with the aid of a MTT (3-4,5-Dimethylthiazol 2,5-diphenyltetrazolium bromide) assay. The data determined that the composite layers did not inhibit the growth and adhesion of MG63 cells to their surfaces exhibiting good biocompatibility properties. Furthermore, the attachment and development of MG63 cells on the surface of MgHApCh composite layers were investigated using atomic force microscopy (AFM). AFM topographical maps emphasized that the HApCh and 8MgHApCh composite layers surface promoted the attachment and proliferation of MG63 cells on their surface. Meanwhile, in the case of 30MgHApCh layers incubated for 48 h, a slight modification of the morphological features of the MG63 cells. In addition, the effects of the composite layers against Candida albicans ATCC 10231 were also evaluated. The data results from the in vitro antifungal assay depicted that the composite layers successfully inhibited the growth of the fungal cells onto their surface. Morphological and fractal analyses unveil cancer cell surfaces on Mg-containing composite layers with intricate 3D patterns, driven by high-frequency components. Their remarkable complexity and roughness arises from a strong multifractal nature, supporting more effective vertical growth compared to Si and HApCh surfaces. The cell viability reduced of uncoated Si surface is highlighted by its less intense 3D pattern growth. Our results show that the uncoated Si surface promotes lower viability of MG63 cancer cells, with less rough and complex 3D spatial patterns.

New Physico-Chemical Analysis of Magnesium-Doped Hydroxyapatite in Dextran Matrix Nanocomposites

The new magnesium-doped hydroxyapatite in dextran matrix (10MgHApD) nanocomposites were synthesized using coprecipitation technique. A spherical morphology was observed by scanning electron microscopy (SEM). The X-ray diffraction (XRD) characterization results show hydroxyapatite hexagonal phase formation. The element map scanning during the EDS analysis revealed homogenous distribution of constituent elements of calcium, phosphor, oxygen and magnesium. The presence of dextran in the sample was revealed by Fourier transform infrared (FTIR) spectroscopy. The antimicrobial activity of the 10MgHAPD nanocomposites was assessed by in vitro assays using Staphylococcus aureus ATCC 25923, Pseudomonas aeruginosa ATCC 27853, Streptococcus mutans ATCC 25175, Porphyromonas gingivalis ATCC 33277 and Candida albicans ATCC 10231 microbial strains. The results of the antimicrobial assays highlighted that the 10MgHApD nanocomposites presented excellent antimicrobial activity against all the tested microorganisms and for all the tested time intervals. Furthermore, the biocompatibility assays determined that the 10MgHApD nanocomposites did not exhibit any toxicity towards Human gingival fibroblast (HGF-1) cells.

Impact of magnesium supplementation on clinical outcome and disease progression of patients with diabetic nephropathy: a prospective randomized trial

Background

Magnesium (Mg) deficiency is closely linked with proteinuria.

Objectives

To assess the impact of oral Mg citrate supplementation on the clinical outcome of diabetic nephropathy (DN) patients.

Design

This was a prospective, randomized, controlled, open-label study.

Methods

Sixty DN patients were recruited from Nephrology and Endocrinology departments, Ain Shams University Hospitals, Cairo, Egypt. Patients were assigned by stratified randomization based on their Mg status, to either Mg citrate group, (n = 30), who received the standard regimen + oral Mg citrate 2.25 g/day or Control group, (n = 30), who received the standard regimen only. The primary endpoint was a change in urinary albumin to creatinine ratio (UACR) after 12 weeks. Secondary outcomes were insulin resistance, glycemic control, lipid profile, serum osteocalcin, quality of life (QoL) and Mg tolerability.

Results

Out of a total of 60 patients enrolled, only 54 patients (26 in Mg citrate group and 28 in the control group) completed the study. Groups were comparable at baseline. The UACR median percent reduction was significantly higher in the Mg citrate group (-6.87%) versus (-0.9%) in the Control group, p = 0.001. After 12 weeks, the estimated glomerular filtration rate significantly improved in the Mg citrate group versus Control group (p = 0.001). Comparable change was observed in glycemic indices. Lipid profile significantly improved in the Mg citrate group versus Control group (p = 0.001). Serum osteocalcin levels significantly declined in the Mg citrate group (p = 0.001) versus control group. Regarding QoL, the total score and all domains significantly improved in the Mg citrate group compared to control. The Mg supplement was tolerable with only mild reported side effects that required no intervention.

Conclusion

Oral Mg citrate supplementation improved microalbuminuria in DN patients. It also had favorable effects on serum osteocalcin, lipid profile and QoL with no reported major side effects.

Trial registration

ClinicalTrials.gov identifier: NCT03824379.

The Effect of Chronic Swimming Exercise and Vitamin E Supplementation on Bone Element Metabolism in Epileptic Rats

INTRODUCTION

This study aimed to investigate the effects of chronic swimming exercise and vitamin E administration on elemental levels in the bone tissue of epileptic rats.

METHODS

Forty-eight rats were divided into six groups: Control, Swimming, Swimming + vitamin E, Swimming + Epilepsy, Swimming + Epilepsy + vitamin E, and Epilepsy. Vitamin E was administered to the animals chronically by gavage at a dose of 500 mg/kg every other day for 3 months. Epileptiform activity was induced with penicillin in animals 24 hours after the last vitamin E intake. The exercise program consisted of daily 30-minute swimming sessions. At the end of the treatment period, the levels of calcium, chromium, copper, iron, magnesium, manganese, lead, and zinc (µg/gram tissue) in bone tissue samples were measured using an atomic emission device.

RESULTS

The results showed that all epileptic groups had significantly lower bone chromium levels compared to the control groups (p<0.05). The epileptic, and epileptic swimming groups had the lowest levels of bone calcium, magnesium, and zinc (p<0.05). Vitamin E administration resulted in a significant increase in bone calcium, magnesium, and zinc levels in the epileptic swimming group with vitamin E compared to the epileptic and epileptic swimming groups. (p<0.05).

CONCLUSION

The findings of the study show that the administration of vitamin E improves calcium, magnesium, and zinc metabolism in the deteriorated bone tissue of the epileptic rat model.

Micronutrient intake to protect against osteoporosis during and after critical illness

PURPOSE OF REVIEW

Improved survival from critical illness has enhanced the focus on ways to augment functional outcomes following discharge from the Intensive Care Unit. An area that is gaining increased attention is the effect of critical illness on bone health and fragility fractures following the episode. This review discusses the micronutrients that may play a role in bone metabolism and the potential benefits of their supplementation to prevent osteoporosis. These include calcium, phosphorous, magnesium, vitamin D, vitamin C, vitamin K, and certain trace elements.

FINDINGS

Although there is sound physiological basis for the involvement of these micronutrients in bone health and fracture prevention, there are few clinically relevant publications in this area with calcium and vitamin D being the best studied to date.

SUMMARY

In the absence of high-quality evidence in critically ill populations, attention to measurement and supplementation of these micronutrients as per current guidelines outlining micronutrient requirements in enteral and parenteral nutrition might mitigate bone loss and its sequelae in the recovery phase from critical illness.