Calcium supplementation for people with overweight or obesity.

BACKGROUND: Obesity is a major health problem worldwide as it can lead to high blood pressure, heart disease, stroke, diabetes, and insulin resistance. The prevalence of overweight and obesity is increasing worldwide across different age groups. There is evidence of an inverse relationship between calcium intake and body weight. The clinical relevance of a small reduction in body weight has been questioned. However, at a population level, a small effect could mitigate the observed global trends. OBJECTIVES: To assess the effects of calcium supplementation on weight loss in individuals living with overweight or obesity. SEARCH METHODS: We searched CENTRAL, MEDLINE, Embase, LILACS (Latin American and Caribbean Health Science Information database), and two clinical trials registries. The date of the last search of all databases (except Embase) was 10 May 2023. No language restrictions were applied. SELECTION CRITERIA: We included randomised controlled trials evaluating the effect of calcium in participants with overweight or obesity of any age or gender. We excluded studies in participants with absorption problems. We included studies of any dose with a minimum duration of two months. We included the following comparisons: calcium supplementation versus placebo, calcium-fortified food or beverage versus placebo, or calcium-fortified food or beverage versus non-calcium-fortified food or beverage. We excluded studies that evaluated the effect of calcium and vitamin D or mixed minerals compared to placebo. DATA COLLECTION AND ANALYSIS: We used standard methodological procedures expected by Cochrane. Our primary outcomes were body weight, health-related quality of life, and adverse events. Our secondary outcomes were anthropometric measures other than body weight, all-cause mortality, and morbidity. MAIN RESULTS: We found 18 studies that evaluated the effect of calcium compared to placebo or control, with a total of 1873 randomised participants (950 participants in the calcium supplementation groups and 923 in the control groups). All included studies gave oral calcium supplementation as the intervention. We did not find any studies evaluating calcium-fortified foods. We excluded 38 studies, identified four ongoing studies, and listed one study as 'awaiting classification'. Sixteen studies compared calcium supplementation to placebo; two studies compared different doses of calcium supplementation. Doses ranged from very low (0.162 g of calcium/day) to high (1.5 g of calcium/day). Most studies were performed in the USA and Iran, lasted less than six months, and included only women. Low-certainty evidence suggests that calcium supplementation compared to placebo or control may result in little to no difference in body weight (mean difference (MD) -0.15 kg, 95% confidence interval (CI) -0.55 to 0.24; P = 0.45, I2 = 46%; 17 studies, 1317 participants; low-certainty evidence). We downgraded the certainty of the evidence by two levels for risk of bias and heterogeneity. None of the included studies reported health-related quality of life, all-cause mortality, or morbidity/complications as outcomes. Only five studies assessed or reported adverse events. Low-certainty evidence suggests a low frequency of adverse events, with no clear difference between intervention and control groups. Moderate-certainty evidence shows that calcium supplementation compared to placebo or control probably results in a small reduction in body mass index (BMI) (MD -0.18 kg/m2,95% CI -0.22 to -0.13; P < 0.001, I2 = 0%; 9 studies, 731 participants) and waist circumference (MD -0.51 cm, 95% CI -0.72 to -0.29; P < 0.001, I2 = 0%; 6 studies, 273 participants). Low-certainty evidence suggests that calcium supplementation compared to placebo or control may result in a small reduction in body fat mass (MD -0.34 kg, 95% CI -0.73 to 0.05; P < 0.001, I2 = 97%; 12 studies, 812 participants). AUTHORS' CONCLUSIONS: Calcium supplementation for eight weeks to 24 months may result in little to no difference in body weight in people with overweight or obesity. The current evidence is of low certainty, due to concerns regarding risk of bias and statistical heterogeneity. We found that the degree of heterogeneity might be partly explained by calcium dosage, the presence or absence of a co-intervention, and whether an intention-to-treat analysis was pursued. While our analyses suggest that calcium supplementation may result in a small reduction in BMI, waist circumference, and fat mass, this evidence is of low to moderate certainty. Future studies could investigate the effect of calcium supplementation on lean body mass to explore if there is a change in body composition.

Analysis of global gene expression using RNA-sequencing reveals novel mechanism of Yanghe Pingchuan decoction in the treatment of asthma.

BACKGROUND: Yanghe Pingchuan decoction (YPD) has been used for asthma treatment for many years in China. We sought to understand the mechanism of YPD, and find more potential targets for YPD-based treatment of asthma. METHODS: An ovalbumin-induced asthma model in rats was created. Staining (hematoxylin and eosin, Masson) was used to evaluate the treatment effect of YPD. RNA-sequencing was carried out to analyze global gene expression, and differentially expressed genes (DEGs) were identified. Analysis of the functional enrichment of genes was done using the Gene Ontology database (GO). Analysis of signaling-pathway enrichment of genes was done using the Kyoto Encyclopedia of Genes and Genomes (KEGG) database. Real-time reverse transcription-quantitative polymerase chain reaction was undertaken to measure expression of DEGs. RESULTS: Pathology showed that YPD had an improvement effect on rats with asthma. RNA-sequencing showed that YPD led to upregulated and downregulated expression of many genes. The YPD-based control of asthma pathogenesis may be related to calcium ion (Ca2+) binding, inorganic cation transmembrane transporter activity, microtubule motor activity, and control of canonical signaling (e.g., peroxisome proliferator-activated receptor, calcium, cyclic adenosine monophosphate). Enrichment analyses suggested that asthma pathogenesis may be related to Ca2 + binding and contraction of vascular smooth muscle. A validation experiment showed that YPD could reduce the Ca2 + concentration by inhibiting the Angiopoietin-II (Ang-II)/Phospholipase (PLA)/calmodulin (CaM0 signaling axis. CONCLUSION: Control of asthma pathogenesis by YPD may be related to inhibition of the Ang-II/PLA/CaM signaling axis, reduction of the Ca2+ concentration, and relaxation of airway smooth muscle (ASM).

Denosumab-induced hypocalcemia in patients with solid tumors and renal dysfunction: a multicenter, retrospective, observational study.

BACKGROUND: Bone metastases are frequently observed in advanced cancer, and bone modifying agents are used to prevent or treat skeletal-related events. Zoledronic acid is contraindicated in patients with severe renal impairment (Ccr < 30 mL/min), but it is not completely known whether denosumab can be used in them. We aimed to determine the association between renal function and hypocalcemia development during denosumab treatment. METHODS: We included patients with solid cancer and bone metastases who started denosumab treatment between April 2017 and March 2019. They were classified into four groups based on creatinine clearance (Ccr; mL/min): normal (Ccr ≥ 80), mild (50 ≤ Ccr ˂80), moderate (30 ≤ Ccr ˂50), and severe (Ccr ˂30). Hypocalcemia was evaluated using the Common Terminology Criteria for Adverse Events (v5.0) based on the albumin-adjusted serum calcium levels; its incidence (stratified by renal function) and risk factors were investigated using a Chi-square test and logistic regression analysis. RESULTS: Of 524 patients (age: 69 ± 11 years; 303 men), 153 had a normal renal function and 222, 117, and 32 had mild, moderate, and severe renal dysfunction. The albumin-adjusted serum calcium level was higher than the measured (total) calcium level in most patients. The incidence of grade ≥ 1 hypocalcemia was 32.0% in the normal group and 37.4%, 29.9%, and 62.5% in the mild, moderate, and severe renal dysfunction groups, respectively. It was, therefore, higher in the severe renal dysfunction groups than in the normal group (P = 0.002). The incidence of grade ≥ 3 hypocalcemia did not differ significantly among the groups. Pre-treatment low serum calcium levels and severe renal dysfunction were risk factors for hypocalcemia. CONCLUSIONS: Evaluating denosumab-induced hypocalcemia required albumin adjustment, and its incidence was high among patients with severe renal dysfunction. Reduced serum calcium levels and severely impaired renal function were associated with an elevated hypocalcemia risk.

Two Randomized Trials of Low-Dose Calcium Supplementation in Pregnancy.

BACKGROUND: The World Health Organization recommends 1500 to 2000 mg of calcium daily as supplementation, divided into three doses, for pregnant persons in populations with low dietary calcium intake in order to reduce the risk of preeclampsia. The complexity of the dosing scheme, however, has led to implementation barriers. METHODS: We conducted two independent randomized trials of calcium supplementation, in India and Tanzania, to assess the noninferiority of a 500-mg daily dose to a 1500-mg daily dose of calcium supplementation. In each trial, the two primary outcomes were preeclampsia and preterm birth, and the noninferiority margins for the relative risks were 1.54 and 1.16, respectively. RESULTS: A total of 11,000 nulliparous pregnant women were included in each trial. The cumulative incidence of preeclampsia was 3.0% in the 500-mg group and 3.6% in the 1500-mg group in the India trial (relative risk, 0.84; 95% confidence interval [CI], 0.68 to 1.03) and 3.0% and 2.7%, respectively, in the Tanzania trial (relative risk, 1.10; 95% CI, 0.88 to 1.36) - findings consistent with the noninferiority of the lower dose in both trials. The percentage of live births that were preterm was 11.4% in the 500-mg group and 12.8% in the 1500-mg group in the India trial (relative risk, 0.89; 95% CI, 0.80 to 0.98), which was within the noninferiority margin of 1.16; in the Tanzania trial, the respective percentages were 10.4% and 9.7% (relative risk, 1.07; 95% CI, 0.95 to 1.21), which exceeded the noninferiority margin. CONCLUSIONS: In these two trials, low-dose calcium supplementation was noninferior to high-dose calcium supplementation with respect to the risk of preeclampsia. It was noninferior with respect to the risk of preterm live birth in the trial in India but not in the trial in Tanzania. (Funded by the Bill and Melinda Gates Foundation and others; ClinicalTrials.gov number, NCT03350516; Clinical Trials Registry-India number, CTRI/2018/02/012119; and Tanzania Medicines and Medical Devices Authority Trials Registry number, TFDA0018/CTR/0010/5).

3D-Cultured Adipose-Derived Stem Cell Spheres Using Calcium-Alginate Scaffolds for Osteoarthritis Treatment in a Mono-Iodoacetate-Induced Rat Model.

Osteoarthritis (OA) is a degenerative disease that causes pain, cartilage deformation, and joint inflammation. Mesenchymal stem cells (MSCs) are potential therapeutic agents for OA treatment. However, the 2D culture of MSCs could potentially affect their characteristics and functionality. In this study, calcium-alginate (Ca-Ag) scaffolds were prepared for human adipose-derived stem cell (hADSC) proliferation with a homemade functionally closed process bioreactor system; the feasibility of cultured hADSC spheres in heterologous stem cell therapy for OA treatment was then evaluated. hADSC spheres were collected from Ca-Ag scaffolds by removing calcium ions via ethylenediaminetetraacetic acid (EDTA) chelation. In this study, 2D-cultured individual hADSCs or hADSC spheres were evaluated for treatment efficacy in a monosodium iodoacetate (MIA)-induced OA rat model. The results of gait analysis and histological sectioning showed that hADSC spheres were more effective at relieving arthritis degeneration. The results of serological and blood element analyses of hADSC-treated rats indicated that the hADSC spheres were a safe treatment in vivo. This study demonstrates that hADSC spheres are a promising treatment for OA and can be applied to other stem cell therapies or regenerative medical treatments.

Chemotherapy Induced Cardiotoxicity: A State of the Art Review on General Mechanisms, Prevention, Treatment and Recent Advances in Novel Therapeutics.

As medicine advances to employ sophisticated anticancer agents to treat a vast array of oncological conditions, it is worth considering side effects associated with several chemotherapeutics. One adverse effect observed with several classes of chemotherapy agents is cardiotoxicity which leads to reduced ejection fraction (EF), cardiac arrhythmias, hypertension and Ischemia/myocardial infarction that can significantly impact the quality of life and patient outcomes. Research into possible mechanisms has elucidated several mechanisms, such as ROS generation, calcium overload and apoptosis. However, there is a relative scarcity of literature detailing the relationship between the exact mechanism of cardiotoxicity for each anticancer agent and observed clinical effects. This review comprehensively describes cardiotoxicity associated with various classes of anticancer agents and possible mechanisms. Further research exploring possible mechanisms for cardiotoxicity observed with anticancer agents could provide valuable insight into susceptibility for developing symptoms and management guidelines. Chemotherapeutics are associated with several side effects. Several classes of chemotherapy agents cause cardiotoxicity leading to a reduced ejection fraction (EF), cardiac arrhythmias, hypertension, and Ischemia/myocardial infarction. Research into possible mechanisms has elucidated several mechanisms, such as ROS generation, calcium overload, and apoptosis. However, there is a relative scarcity of literature detailing the relationship between the exact mechanism of cardiotoxicity for each anticancer agent and observed clinical effects. This review describes cardiotoxicity associated with various classes of anticancer agents and possible mechanisms. Further research exploring mechanisms for cardiotoxicity observed with anticancer agents could provide insight that will guide management.

Use of calcium-containing bioactive desensitizers in dental bleaching: A systematic review and meta-analysis.

BACKGROUND: Topical application of calcium-containing bioactive desensitizers (CBs) has been used to minimize bleaching-induced tooth sensitivity (TS). This study answered the research question "Is the risk of TS lower when CBs are used with dental bleaching in adults compared with bleaching without desensitizers?" TYPES OF STUDIES REVIEWED: The authors included randomized clinical trials comparing topical CB application with a placebo or no intervention during bleaching. Searches for eligible articles were performed in MEDLINE via PubMed, Cochrane Library, Brazilian Library in Dentistry, Latin American and Caribbean Health Sciences Literature, Scopus, Web of Science, Embase, and gray literature without language and date restrictions and updated in September 2022. The risk of bias was evaluated using Risk of Bias Version 2.0. The authors conducted meta-analyses with the random-effects model. The authors assessed heterogeneity with the Cochrane Q test, I2 statistics, and prediction interval. The authors used the Grading of Recommendations Assessment, Development and Evaluation approach to assess the certainty of the evidence. RESULTS: After database screening, 22 studies remained, with most at high risk of bias. No difference in the risk of TS was detected (risk ratio, 0.95; 95% CI, 0.90 to 1.01; P = .08, low certainty). In a visual analog scale, the intensity of TS (mean difference, -0.98; 95% CI, -1.36 to -0.60; P < .0001, very low certainty) was lower for the CB group. The color change was unaffected (P > .08). PRACTICAL IMPLICATIONS: Although topical CB dental bleaching did not reduce the risk of TS and color change, these agents slightly reduced the TS intensity, but the certainty of the evidence is very low.

MicroRNA-7a-5p ameliorates diabetic peripheral neuropathy by regulating VDAC1/JNK/c-JUN pathway.

AIMS: The pathogenesis of diabetic peripheral neuropathy (DPN) is complex, and its treatment is extremely challenging. MicroRNA-7a-5p (miR-7a-5p) has been widely reported to alleviate apoptosis and oxidative stress in various diseases. This study aimed to investigate the mechanism of miR-7a-5p in DPN. METHODS: DPN cell model was constructed with high-glucose-induced RSC96 cells. Cell apoptosis and viability were detected by flow cytometry analysis and cell counting kit-8 (CCK-8) assay respectively. The apoptosis and Jun N-terminal kinase (JNK)/c-JUN signalling pathway-related proteins expression were detected by Western blotting. The intracellular calcium content and oxidative stress levels were detected by flow cytometry and reagent kits. Mitochondrial membrane potential was evaluated by tetrechloro-tetraethylbenzimidazol carbocyanine iodide (JC-1) staining. The targeting relationship between miR-7a-5p and voltage-dependent anion-selective channel protein 1 (VDAC1) was determined by RNA pull-down assay and dual-luciferase reporter gene assay. The streptozotocin (STZ) rat model was constructed to simulate DPN in vivo. The paw withdrawal mechanical threshold (PTW) was measured by Frey capillary line, and the motor nerve conduction velocity (MNCV) was measured by electromyography. RESULTS: MiR-7a-5p expression was decreased, while VDAC1 expression was increased in HG-induced RSC96 cells and STZ rats. In HG-induced RSC96 cells, miR-7a-5p overexpression promoted cell proliferation, inhibited apoptosis, down-regulated calcium release, improved mitochondrial membrane potential and repressed oxidative stress response. MiR-7a-5p negatively regulated VDAC1 expression. VDAC1 knockdown improved cell proliferation activity, suppressed cell apoptosis and mitochondrial dysfunction by inhibiting JNK/c-JUN pathway activation. MiR-7a-5p overexpression raised PTW, restored MNCV and reduced oxidative stress levels and nerve cell apoptosis in STZ rats. CONCLUSION: MiR-7a-5p overexpression ameliorated mitochondrial dysfunction and inhibited apoptosis in DPN by regulating VDAC1/JNK/c-JUN pathway.

Vitamin A-Induced Hypercalcemia in Burn Patients: A Case Study.

Vitamin and steroid supplementation such as oxandrolone are commonly given to speed the recovery process in severe burn injuries. Vitamin A is administered concurrently with steroids because of its pro-inflammatory and positive effects on wound healing. However, vitamin A supplementation warrants caution as hypercalcemia can result from vitamin A overdose. Our case involves an 18-year-old male injured in an oil field explosion who presented with 55% total body surface area (TBSA) partial- and full-thickness burns. Following successful resuscitation, he was given vitamin A, oxandrolone, vitamin C, and zinc sulfate as part of the standard vitamin supplementation. On hospital day (HD) 33, serum calcium levels were noted to be elevated and increased to 13 mg/dL a few days later. Parathyroid hormone and vitamin D levels were found to be within normal range, and urine analysis showed normal calcium excretion. Subsequent assessment of vitamin A levels revealed significantly elevated levels at 93 mcg/dL. Vitamin A supplementation was discontinued, and the patient was discharged on HD 42. At the 1-month follow-up, serum calcium levels were normal, which links the hypercalcemia to vitamin A overdose. This case highlights the importance of considering vitamin A overdose as a cause for asymptomatic hypercalcemia with a normal parathyroid and vitamin D workup. While routine, vitamin A supplementation in burn patients calls for assessment of both serum calcium and vitamin A levels throughout the hospital stay to prevent hypercalcemia and its negative effects.

Calcium chloride for the prevention of uterine atony during cesarean delivery: A pilot randomized controlled trial and pharmacokinetic study.

STUDY OBJECTIVE: To assess the feasibility, patient tolerance, pharmacokinetics, and potential effectiveness of a randomized controlled trial protocol investigating intravenous calcium chloride for the prevention of uterine atony during cesarean delivery. DESIGN: Double-blind, randomized controlled pilot trial with nested population pharmacokinetic analysis. SETTING: This study was performed at Lucile Packard Children's Hospital, from August 2018 to September 2019. PATIENTS: Forty patients with at least two risk factors for uterine atony at the time of cesarean delivery. INTERVENTIONS: One gram of intravenous calcium chloride (n = 20 patients) or a saline placebo control (n = 20 patients), in addition to standard care with oxytocin, upon umbilical cord clamping. MEASUREMENTS: The primary efficacy-related outcome was the presence of uterine atony defined as the use of a second-line uterotonic medication, surgical interventions for atony, or hemorrhage with blood loss >1000 mL. Blood loss, uterine tone numerical rating scores, serial venous blood calcium levels, hemodynamics, and potential side effects were also assessed. MAIN RESULTS: The study protocol proved feasible. The incidence of atony was 20% in parturients who received calcium compared to 50% in the placebo group (relative risk 0.38, P = 0.07, 95% CI 0.15-1.07, NNT 3.3). Calcium recipients tolerated the drug infusion well, with no adverse events and an equal incidence of potential side effects in the calcium and placebo groups. Ionized calcium concentration rose significantly in all patients who received calcium infusion, from baseline 1.18 mmol/L to peak levels 1.50-1.60 mmol/L. One-compartment population pharmacokinetics established clearance of 0.93 (95% CI 0.63-1.52) L/min and volume of distribution 76 (95% CI 49-94) L. CONCLUSIONS: In this pilot study, investigators found that intravenous calcium chloride was well-tolerated by the 20 patients assigned to receive the study drug and may be effective in prevention of uterine atony. A 1-g dose was sufficient to substantially increase calcium levels without any critically elevated lab values or concern for adverse side effects. These encouraging findings warrant further investigation of calcium as a novel agent to prevent uterine atony with an adequately powered clinical trial. Clinical trial registry NCT03867383 https://clinicaltrials.gov/ct2/show/NCT03867383.

The effects of doxorubicin on cardiac calcium homeostasis and contractile function.

Cancer is one of the leading causes of death globally and the number of cancer deaths is rising as a result of increased longevity. Doxorubicin (DOX) is one of the most effective anti-neoplastic drugs used to treat various forms of cancer. However, its therapeutic utility is limited by its associated cardiotoxicity, specifically cardiac contractile dysfunction. Current evidence indicates that interference with cardiac intracellular calcium (Ca2+) homeostasis is one of the major causes among the molecular and cellular determinants of DOX-induced cardiotoxicity. This contributes to the development of cardiac contractile dysfunction, which remains a major concern and obstacle in clinical applications. This review comprehensively summarizes the effects of DOX on cardiac Ca2+ homeostasis and contractile function from in vitro, ex vivo, and in vivo studies. It also highlights the information essential for the potential interventions which may support the therapeutic effectiveness in clinical practice for the attenuation of cardiotoxicity in DOX-treated patients.

Cardioprotective effect of fingolimod against calcium paradox-induced myocardial injury in the isolated rat heart.

Fingolimod (FTY720) inhibits Ca2+-permeable, Mg2+-sensitive channels called transient receptor potential melastatin 7 (TRPM7), but its effects on Ca2+ paradox (CP) - induced myocardial damage has not been evaluated. We studied the effect of FTY720 on CP-induced myocardial damage and used other TRPM7 channel inhibitors nordihydroguaiaretic acid (NDGA) and Mg2+ to test if any effect of FTY720 was via TRPM7 inhibition. Langendorff-perfused Wistar rat hearts were treated with FTY720 or NDGA and subjected to a CP protocol consisting of Ca2+ depletion followed by Ca2+ repletion. Hearts of rats pre-treated with MgSO4 were also subjected to CP. Hemodynamic parameters were measured using an intraventricular balloon, and myocardial infarct size was quantified using triphenyltetrazolium chloride stain. TRPM7 proteins in ventricular tissue were detected using immunoblot analysis. FTY720, but not NDGA, decreased CP-induced infarct size. Both FTY720 and NDGA minimized the CP-induced elevation of left ventricular end-diastolic pressure, but only FTY720 ultimately improved ventricular developed pressure. Mg2+ pre-treatment had no effect on CP-induced infarct size, nor hemodynamic parameters during CP, nor the level of TRPM7 protein expression in ventricular tissue. Overall, FTY720 attenuated CP-induced myocardial damage, with potential therapeutic implications on Ca2+-mediated cardiotoxicity; however, the cardioprotective mechanism of FTY720 seems to be unrelated to TRPM7 channel modulation.

QbD enabled Process Variable Study to Develop Sustained Release Chitosan-Alginate Embedded Delivery System for Improved Patient Compliance

Abstract The current investigation entail systematic Quality by Design (QbD)-enabled approach for the development of Sustained released embedded drug delivery systems of L-Arginine employing ionic gelation technique to attain improved patient compliance. Hence, in this QbD enabled systematic approach; quality target product profile (QTTP) was defined and critical quality attributes (CQAs) were identified. Further the risk assessment studies were undertaken through Ishikawa fish bone diagram to locate the critical material attributes (CMAs) and/or critical process parameters (CPPs) for the formulation of beads that may affect CQAs of drug product. A face centered central composite design (CCD) for two factors at three levels each with α =1 was employed for the optimization process to checkout the impact of concentration of sodium alginate and concentration of chitosan as CMAs which wereprior identified from risk assessment study and further evaluated for CQAs viz. bead size, swelling index and percent drug entrapment. The optimum formulation was embarked upon by using mathematical model being developed yielding desired CQAs. Thereby chitosan coated calcium-alginate delivery system was successfully developed by strategically employing QbD approach.In a nutshell, the presentinvestigation reports the successful development of optimized chitosan coated alginate beads employing QbD approach which can serve as a platform for other drugs too.

Calcium and Vitamin D Supplementation and Their Association with Kidney Stone Disease: A Narrative Review.

Kidney stone disease is a multifactorial condition influenced by both genetic predisposition and environmental factors such as lifestyle and dietary habits. Although different monogenic polymorphisms have been proposed as playing a causal role for calcium nephrolithiasis, the prevalence of these mutations in the general population and their complete pathogenetic pathway is yet to be determined. General dietary advice for kidney stone formers includes elevated fluid intake, dietary restriction of sodium and animal proteins, avoidance of a low calcium diet, maintenance of a normal body mass index, and elevated intake of vegetables and fibers. Thus, balanced calcium consumption protects against the risk for kidney stones by reducing intestinal oxalate availability and its urinary excretion. However, calcium supplementation given between meals might increase urinary calcium excretion without the beneficial effect on oxalate. In kidney stone formers, circulating active vitamin D has been found to be increased, whereas higher plasma 25-hydroxycholecalciferol seems to be present only in hypercalciuric patients. The association between nutritional vitamin D supplements and the risk for stone formation is currently not completely understood. However, taken together, available evidence might suggest that vitamin D administration worsens the risk for stone formation in patients predisposed to hypercalciuria. In this review, we analyzed and discussed available literature on the effect of calcium and vitamin D supplementation on the risk for kidney stone formation.

Assessment of the Methods Used to Develop Vitamin D and Calcium Recommendations-A Systematic Review of Bone Health Guidelines.

BACKGROUND: There are numerous guidelines developed for bone health. Yet, it is unclear whether the differences in guideline development methods explain the variability in the recommendations for vitamin D and calcium intake. The objective of this systematic review was to collate and compare recommendations for vitamin D and calcium across bone health guidelines, assess the methods used to form the recommendations, and explore which methodological factors were associated with these guideline recommendations. METHODS: We searched MEDLINE, EMBASE, CINAHL, and other databases indexing guidelines to identify records in English between 2009 and 2019. Guidelines or policy statements on bone health or osteoporosis prevention for generally healthy adults aged ≥40 years were eligible for inclusion. Two reviewers independently extracted recommendations on daily vitamin D and calcium intake, supplement use, serum 25 hydroxyvitamin D [25(OH)D] level, and sunlight exposure; assessed guideline development methods against 25 recommended criteria in the World Health Organization (WHO) handbook for guideline development; and, identified types identified types of evidence underpinning the recommendations. RESULTS: we included 47 eligible guidelines from 733 records: 74% of the guidelines provided vitamin D (200~600-4000 IU/day) and 70% provided calcium (600-1200 mg/day) recommendations, 96% and 88% recommended vitamin D and calcium supplements, respectively, and 70% recommended a specific 25(OH)D concentration. On average, each guideline met 10 (95% CI: 9-12) of the total of 25 methodological criteria for guideline development recommended by the WHO Handbook. There was uncertainty in the association between the methodological criteria and the proportion of guidelines that provided recommendations on daily vitamin D or calcium. Various types of evidence, including previous bone guidelines, nutrient reference reports, systematic reviews, observational studies, and perspectives/editorials were used to underpin the recommendations. CONCLUSIONS: There is considerable variability in vitamin D and calcium recommendations and in guideline development methods in bone health guidelines. Effort is required to strengthen the methodological rigor of guideline development and utilize the best available evidence to underpin nutrition recommendations in evidence-based guidelines on bone health.

The Activation of ROS/NF-κB/MMP-9 Pathway Promotes Calcium-Induced Kidney Crystal Deposition.

Idiopathic hypercalciuria is an important risk factor for the formation of calcium-containing kidney stones. Matrix metalloproteinase-9 (MMP-9) is closely related to cell and tissue remodeling and is involved in ectopic tissue calcification. However, little is known about its role in kidney stone formation. In this study, we found that the expression of MMP-9 and that of osteoblastic-related proteins was increased in normal rat kidney epithelial-like (NRK-52E) cells following treatment with a high concentration of calcium, while the knockout or overexpression of MMP-9 could, respectively, significantly inhibit or upregulate the expression of osteoblastic-related proteins and calcium crystal deposition. In addition, apoptosis and calcium crystal deposition were significantly reduced in Sprague-Dawley rats with 1,25(OH)2D3-induced hypercalciuria following MMP-9 inhibitor I treatment. Furthermore, inhibiting reactive oxygen species (ROS) production or the nuclear factor kappa-light-chain-enhancer of activated B cell (NF-κB) pathway significantly reduced calcium-induced MMP-9 expression and calcium crystal deposition. In summary, our results suggested that a high calcium concentration promotes epithelial-osteoblastic transformation and calcium crystal deposition in renal tubule cells by regulating the ROS/NF-κB/MMP-9 axis and identified a novel role for MMP-9 in regulating calcium-induced calcium crystal deposition in renal tubules.

Hydroxysafflor Yellow A Ameliorates Myocardial Ischemia/Reperfusion Injury by Suppressing Calcium Overload and Apoptosis.

Myocardial ischemia/reperfusion injury (MI/RI) is an urgent problem with a great impact on health globally. However, its pathological mechanisms have not been fully elucidated. Hydroxysafflor yellow A (HSYA) has a protective effect against MI/RI. This study is aimed at further clarifying the relationship between HSYA cardioprotection and calcium overload as well as the underlying mechanisms. We verified the protective effect of HSYA on neonatal rat primary cardiomyocytes (NPCMs) and human-induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) from hypoxia-reoxygenation (HR) injury. To explore the cardioprotective mechanism of HSYA, we employed calcium fluorescence, TUNEL assay, JC-1 staining, and western blotting. Finally, cardio-ECR and patch-clamp experiments were used to explain the regulation of L-type calcium channels (LTCC) in cardioprotection mediated by HSYA. The results showed that HSYA reduced the levels of myocardial enzymes and protected NPCMs from HR injury. HSYA also restored the contractile function of hiPSC-CMs and field potential signal abnormalities caused by HR and exerted a protective effect on cardiac function. Further, we demonstrated that HSYA protects cardiomyocytes from HR injury by decreasing mitochondrial membrane potential and inhibiting apoptosis and calcium overload. Patch-clamp results revealed that MI/RI caused a sharp increase in calcium currents, which was inhibited by pretreatment with HSYA. Furthermore, we found that HSYA restored contraction amplitude, beat rate, and field potential duration of hiPSC-CMs, which were disrupted by the LTCC agonist Bay-K8644. Patch-clamp experiments also showed that HSYA inhibits Bay-K8644-induced calcium current, with an effect similar to that of the LTCC inhibitor nisoldipine. Therefore, our data suggest that HSYA targets LTCC to inhibit calcium overload and apoptosis of cardiomyocytes, thereby exerting a cardioprotective effect and reducing MI/RI injury.

Osteopontin isoform c promotes the survival of cisplatin-treated NSCLC cells involving NFATc2-mediated suppression on calcium-induced ROS levels.

BACKGROUND: Tumor microenvironment (TME) critically contributed to the malignant progression of transformed cells and the chemical responses to chemotherapy reagents. Osteopontin (OPN) is a secretory onco-protein with several splicing isoforms, all of which were known to regulate tumor growth and able to alter cell-cell or cell-TME communication, however, the exact role and regulation of the OPN splicing isoforms was not well understood. METHODS: In this study, the effects of conditioned medium from the culture of OPN splicing isoforms overexpressing cells on cell functions were evaluated. The methods of nuclear calcium reporter assays and subcellular distribution of nuclear factor of activated T cells c2 (NFATc2) assays were used to investigate the molecular mechanism underlining the roles of OPN splicing isoforms. RESULTS: We found that the survival of NSCLC cells treated with cisplatin was increased by secretory OPNc in the condition medium, where reduction of apoptosis by OPNc was associated with the activation of cellular calcium signals and subsequent nuclear translocation of NFATc2. CONCLUSIONS: The results revealed a mechanism of OPN and downstream signal for tumor cells to survive in chemo-stressed TME, which emphasized the importance of secretory proteins in alternative splicing isoforms. Our study not only demonstrated the importance of OPN neutralization for anti-tumor effects, but also implied that modulation in calcium/NFATc2/ROS axis could be a novel approach for improving the long-term outcome of NSCLC treatment.

Very High Coronary Artery Calcium (≥1000) and Association With Cardiovascular Disease Events, Non-Cardiovascular Disease Outcomes, and Mortality: Results From MESA.

BACKGROUND: There are limited data on the unique cardiovascular disease (CVD), non-CVD, and mortality risks of primary prevention individuals with very high coronary artery calcium (CAC; ≥1000), especially compared with rates observed in secondary prevention populations. METHODS: Our study population consisted of 6814 ethnically diverse individuals 45 to 84 years of age who were free of known CVD from MESA (Multi-Ethnic Study of Atherosclerosis), a prospective, observational, community-based cohort. Mean follow-up time was 13.6±4.4 years. Hazard ratios of CAC ≥1000 were compared with both CAC 0 and CAC 400 to 999 for CVD, non-CVD, and mortality outcomes with the use of Cox proportional hazards regression adjusted for age, sex, and traditional risk factors. Using a sex-adjusted logarithmic model, we calculated event rates in MESA as a function of CAC and compared them with those observed in the placebo group of stable secondary prevention patients in the FOURIER clinical trial (Further Cardiovascular Outcomes Research With PCSK9 Inhibition in Subjects With Elevated Risk). RESULTS: Compared with CAC 400 to 999, those with CAC ≥1000 (n=257) had a greater mean number of coronary vessels with CAC (3.4±0.5), greater total area of CAC (586.5±275.2 mm2), similar CAC density, and more extensive extracoronary calcification. After full adjustment, CAC ≥1000 demonstrated a 4.71- (3.63-6.11), 7.57- (5.50-10.42), 4.86-(3.32-7.11), and 1.94-fold (1.57-2.41) increased risk for all CVD events, all coronary heart disease events, hard coronary heart disease events, and all-cause mortality, respectively, compared with CAC 0 and a 1.65- (1.25-2.16), 1.66- (1.22-2.25), 1.51- (1.03-2.23), and 1.34-fold (1.05-1.71) increased risk compared with CAC 400 to 999. With increasing CAC, hazard ratios increased for all event types, with no apparent upper CAC threshold. CAC ≥1000 was associated with a 1.95- (1.57-2.41) and 1.43-fold (1.12-1.83) increased risk for a first non-CVD event compared with CAC 0 and CAC 400 to 999, respectively. CAC 1000 corresponded to an annualized 3-point major adverse cardiovascular event rate of 3.4 per 100 person-years, similar to that of the total FOURIER population (3.3) and higher than those of the lower-risk FOURIER subgroups. CONCLUSIONS: Individuals with very high CAC (≥1000) are a unique population at substantially higher risk for CVD events, non-CVD outcomes, and mortality than those with lower CAC, with 3-point major adverse cardiovascular event rates similar to those of a stable treated secondary prevention population. Future guidelines should consider a less distinct stratification algorithm between primary and secondary prevention patients in guiding aggressive preventive pharmacotherapy.