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Elena Valassi Endocrinology/Medicine Department, Hospital Sant Pau, Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER, Unidad 747), IIB-Sant Pau, ISCIII and Universitat Autònoma de Barcelona (UAB), Barcelona, Spain

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Natalia García-Giralt URFOA, IMIM (Institut Hospital del Mar d’Investigacions Mèdiques), Universitat Autònoma de Barcelona, Barcelona, Spain

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Jorge Malouf Mineral Metabolism Unit, Medicine Department, Hospital Sant Pau, Barcelona, Spain

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Iris Crespo Endocrinology/Medicine Department, Hospital Sant Pau, Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER, Unidad 747), IIB-Sant Pau, ISCIII and Universitat Autònoma de Barcelona (UAB), Barcelona, Spain

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Jaume Llauger Radiology Department, Hospital Sant Pau, Barcelona, Spain

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Adolfo Díez-Pérez URFOA, IMIM (Institut Hospital del Mar d’Investigacions Mèdiques), Universitat Autònoma de Barcelona, Barcelona, Spain

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Susan M Webb Endocrinology/Medicine Department, Hospital Sant Pau, Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER, Unidad 747), IIB-Sant Pau, ISCIII and Universitat Autònoma de Barcelona (UAB), Barcelona, Spain

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Background

Biochemical control of GH/IGF-I excess in acromegaly (ACRO) is associated with persistent impairment of trabecular microstructure leading to increased risk of vertebral fractures. Circulating miRNAs modulate the activity of osteoblasts and osteoclasts, and may be potential biomarkers of osteoporosis.

Aims

Identify differentially expressed miRNAs in the serum of patients with controlled ACRO vs controls and correlate miRNA levels with both biochemical and structural bone parameters.

Patients and methods

Twenty-seven patients with controlled ACRO (11 males, 16 females; mean age, 48 ± 5 years; BMI, 28 ± 4 kg/m2) and 27 age-, gender- and BMI-matched controls were recruited. Areal BMD at lumbar spine and femur, and trabecular bone score were assessed; volumetric BMD was measured by quantitative computed tomography QCT-Pro (Mindways). Twenty miRNAs, chosen by their putative role in bone, were quantified in serum using real-time qPCR.

Results

In ACRO patients, miR-103a-3p and miR-191-5p were found overexpressed, whereas miR-660-5p was underexpressed (P < 0.001). miR-103a-3p levels were negatively associated with both trabecular vBMD at trochanter and serum osteoprotegerin concentrations (P < 0.05) and positively with vitamin D concentrations (P < 0.01) and total cross-sectional area of the femoral neck (P < 0.05). miR-660-5p levels were correlated with both trabecular vBMD at trochanter and OPG concentrations (P < 0.05), but were negatively associated with vitamin D levels (P < 0.05). A negative correlation between miR-103-a-3p and miR-660-5p was found in both groups (P < 0.001).

Conclusions

Circulating miR-103a-3p and miR-660-5p are differentially expressed in controlled ACRO patients and associated with bone structural parameters. miRNAs may be one of the mechanisms involved in the pathogenesis of bone disease and could be used as biomarkers in ACRO patients.

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Fabienne A U Fox Population Health Sciences, German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany

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Lennart Koch Population Health Sciences, German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
University for Health Sciences, Medical Informatics and Technology (UMIT TIROL), Tirol, Austria

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Monique M B Breteler Population Health Sciences, German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
Institute for Medical Biometry, Informatics and Epidemiology (IMBIE), Faculty of Medicine, University of Bonn, Bonn, Germany

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N Ahmad Aziz Population Health Sciences, German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
Department of Neurology, Faculty of Medicine, University of Bonn, Bonn, Germany

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Objective

Maintaining muscle function throughout life is critical for healthy ageing. Although in vitro studies consistently indicate beneficial effects of 25-hydroxyvitamin D (25-OHD) on muscle function, findings from population-based studies remain inconclusive. We therefore aimed to examine the association between 25-OHD concentration and handgrip strength across a wide age range and assess potential modifying effects of age, sex and season.

Methods

We analysed cross-sectional baseline data of 2576 eligible participants out of the first 3000 participants (recruited from March 2016 to March 2019) of the Rhineland Study, a community-based cohort study in Bonn, Germany. Multivariate linear regression models were used to assess the relation between 25-OHD levels and grip strength while adjusting for age, sex, education, smoking, season, body mass index, physical activity levels, osteoporosis and vitamin D supplementation.

Results

Compared to participants with deficient 25-OHD levels (<30 nmol/L), grip strength was higher in those with inadequate (30 to <50 nmol/L) and adequate (≥50 to ≤125 nmol/L) levels (ß inadequate = 1.222, 95% CI: 0.377; 2.067, P = 0.005; ß adequate = 1.228, 95% CI: 0.437; 2.019, P = 0.002). Modelling on a continuous scale revealed grip strength to increase with higher 25-OHD levels up to ~100 nmol/L, after which the direction reversed (ß linear = 0.505, 95% CI: 0.179; 0.830, P = 0.002; ß quadratic = –0.153, 95% CI: –0.269; -0.038, P = 0.009). Older adults showed weaker effects of 25-OHD levels on grip strength than younger adults (ß 25OHDxAge = –0.309, 95% CI: –0.594; –0.024, P = 0.033).

Conclusions

Our findings highlight the importance of sufficient 25-OHD levels for optimal muscle function across the adult life span. However, vitamin D supplementation should be closely monitored to avoid detrimental effects.

Open access
J A Tamblyn Institute of Metabolism and Systems Research (IMSR), College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK
Birmingham Women’s Foundation Hospital, Edgbaston, Birmingham, UK
Centre for Endocrinology, Diabetes and Metabolism, Birmingham Health Partners, Birmingham, UK

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C Jenkinson Birmingham Women’s Foundation Hospital, Edgbaston, Birmingham, UK

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D P Larner Birmingham Women’s Foundation Hospital, Edgbaston, Birmingham, UK

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M Hewison Institute of Metabolism and Systems Research (IMSR), College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK
Centre for Endocrinology, Diabetes and Metabolism, Birmingham Health Partners, Birmingham, UK

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M D Kilby Institute of Metabolism and Systems Research (IMSR), College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK
Birmingham Women’s Foundation Hospital, Edgbaston, Birmingham, UK
Centre for Endocrinology, Diabetes and Metabolism, Birmingham Health Partners, Birmingham, UK

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Vitamin D deficiency is common in pregnant women and may contribute to adverse events in pregnancy such as preeclampsia (PET). To date, studies of vitamin D and PET have focused primarily on serum concentrations vitamin D, 25-hydroxyvitamin D3 (25(OH)D3) later in pregnancy. The aim here was to determine whether a more comprehensive analysis of vitamin D metabolites earlier in pregnancy could provide predictors of PET. Using samples from the SCOPE pregnancy cohort, multiple vitamin D metabolites were quantified by liquid chromatography–tandem mass spectrometry in paired serum and urine prior to the onset of PET symptoms. Samples from 50 women at pregnancy week 15 were analysed, with 25 (50%) developing PET by the end of the pregnancy and 25 continuing with uncomplicated pregnancy. Paired serum and urine from non-pregnant women (n = 9) of reproductive age were also used as a control. Serum concentrations of 25(OH)D3, 25(OH)D2, 1,25(OH)2D3, 24,25(OH)2D3 and 3-epi-25(OH)D3 were measured and showed no significant difference between women with uncomplicated pregnancies and those developing PET. As previously reported, serum 1,25(OH)2D3 was higher in all pregnant women (in the second trimester), but serum 25(OH)D2 was also higher compared to non-pregnant women. In urine, 25(OH)D3 and 24,25(OH)2D3 were quantifiable, with both metabolites demonstrating significantly lower (P < 0.05) concentrations of both of these metabolites in those destined to develop PET. These data indicate that analysis of urinary metabolites provides an additional insight into vitamin D and the kidney, with lower urinary 25(OH)D3 and 24,25(OH)2D3 excretion being an early indicator of a predisposition towards developing PET.

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Behnaz Abiri Obesity Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran

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Majid Valizadeh Obesity Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran

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Amirhossein Ramezani Ahmadi Isfahan Endocrine and Metabolism Research Center, Isfahan University of Medical Sciences, Isfahan, Iran

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Shirin Amini Department of Nutrition, Shoushtar Faculty of Medical Sciences, Shoushtar, Iran

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Mohammad Nikoohemmat Obesity Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran

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Faeze Abbaspour Obesity Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran

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Farhad Hosseinpanah Obesity Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran

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Objectives

It has not been established whether vitamin D deficiency is associated with anthropometric state; therefore, this systematic review examined the relationship between serum vitamin D levels with anthropometrics and adiposity across different ages.

Methods

Studies that examined vitamin D deficiency with adiposity measures in different age groups were searched in the PubMed, Scopus, Embase, and Google Scholar databases until November 2023. Two investigators independently reviewed titles and abstracts, examined full-text articles, extracted data, and rated the quality in accordance with the Newcastle–Ottawa criteria.

Results

Seventy-two studies, with a total of 59,430 subjects, were included. Of these studies, 27 cross-sectional studies and one longitudinal study (with 25,615 participants) evaluated the possible link between 25(OH)D serum concentrations and anthropometric/adiposity indices in the pediatric population. Forty-two cross-sectional studies and two cohort investigations (with 33,815 participants) investigated the relationship between serum 25(OH)D levels and adiposity measures in adults and/or the elderly population. There is evidence supporting links between vitamin D deficiency and obesity, and revealed an inverse association between vitamin D and adiposity indicators, specifically in female subjects. However, the effects of several confounding factors should also be considered.

Conclusion

Most published studies, most of which were cross-sectional, reported a negative association between vitamin D and female adiposity indicators. Therefore, serum vitamin D levels should be monitored in overweight/obese individuals.

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Silvia Ciancia Department of Internal Medicine and Pediatrics, Ghent University, Ghent, Belgium

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Vanessa Dubois Basic and Translational Endocrinology (BaTE), Department of Basic and Applied Medical Sciences, Faculty of Medicine and Health Sciences, Ghent University, Ghent, Belgium

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Martine Cools Department of Internal Medicine and Pediatrics, Ghent University, Pediatric Endocrinology Service, Ghent University Hospital, Ghent, Belgium

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Both in the United States and Europe, the number of minors who present at transgender healthcare services before the onset of puberty is rapidly expanding. Many of those who will have persistent gender dysphoria at the onset of puberty will pursue long-term puberty suppression before reaching the appropriate age to start using gender-affirming hormones. Exposure to pubertal sex steroids is thus significantly deferred in these individuals. Puberty is a critical period for bone development: increasing concentrations of estrogens and androgens (directly or after aromatization to estrogens) promote progressive bone growth and mineralization and induce sexually dimorphic skeletal changes. As a consequence, safety concerns regarding bone development and increased future fracture risk in transgender youth have been raised. We here review published data on bone development in transgender adolescents, focusing in particular on differences in age and pubertal stage at the start of puberty suppression, chosen strategy to block puberty progression, duration of puberty suppression, and the timing of re-evaluation after estradiol or testosterone administration. Results consistently indicate a negative impact of long-term puberty suppression on bone mineral density, especially at the lumbar spine, which is only partially restored after sex steroid administration. Trans girls are more vulnerable than trans boys for compromised bone health. Behavioral health measures that can promote bone mineralization, such as weight-bearing exercise and calcium and vitamin D supplementation, are strongly recommended in transgender youth, during the phase of puberty suppression and thereafter.

Open access
Elisabet Einarsdottir Folkhälsan Institute of Genetics, University of Helsinki, Helsinki, Finland
Molecular Neurology Research Program, University of Helsinki, Helsinki, Finland
Department of Biosciences and Nutrition, Karolinska Institutet, Huddinge, Sweden

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Minna Pekkinen Folkhälsan Institute of Genetics, University of Helsinki, Helsinki, Finland
Children’s Hospital, University of Helsinki and Helsinki University Hospital, Helsinki, Finland

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Kaarel Krjutškov Molecular Neurology Research Program, University of Helsinki, Helsinki, Finland
Competence Centre on Health Technologies, Tartu, Estonia

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Shintaro Katayama Department of Biosciences and Nutrition, Karolinska Institutet, Huddinge, Sweden

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Juha Kere Folkhälsan Institute of Genetics, University of Helsinki, Helsinki, Finland
Molecular Neurology Research Program, University of Helsinki, Helsinki, Finland
Department of Biosciences and Nutrition, Karolinska Institutet, Huddinge, Sweden
School of Basic and Medical Biosciences, King’s College London, Guy’s Hospital, London, United Kingdom

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Outi Mäkitie Folkhälsan Institute of Genetics, University of Helsinki, Helsinki, Finland
Children’s Hospital, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
Department of Molecular Medicine and Surgery and Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden
Department of Clinical Genetics, Karolinska University Hospital, Stockholm, Sweden

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Heli Viljakainen Folkhälsan Institute of Genetics, University of Helsinki, Helsinki, Finland
Department of Food and Environmental Sciences, University of Helsinki, Helsinki, Finland

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Objective

The effect of vitamin D at the transcriptome level is poorly understood, and furthermore, it is unclear if it differs between obese and normal-weight subjects. The objective of the study was to explore the transcriptome effects of vitamin D supplementation.

Design and methods

We analysed peripheral blood gene expression using GlobinLock oligonucleotides followed by RNA sequencing in individuals participating in a 12-week randomised double-blinded placebo-controlled vitamin D intervention study. The study involved 18 obese and 18 normal-weight subjects (of which 20 males) with mean (±s.d.) age 20.4 (±2.5) years and BMIs 36 (±10) and 23 (±4) kg/m2, respectively. The supplemental daily vitamin D dose was 50 µg (2000 IU). Data were available at baseline, 6- and 12-week time points and comparisons were performed between the vitamin D and placebo groups separately in obese and normal-weight subjects.

Results

Significant transcriptomic changes were observed at 6 weeks, and only in the obese subjects: 1724 genes were significantly upregulated and 186 genes were downregulated in the vitamin D group compared with placebo. Further analyses showed several enriched gene categories connected to mitochondrial function and metabolism, and the most significantly enriched pathway was related to oxidative phosphorylation (adjusted P value 3.08 × 10−14). Taken together, our data suggest an effect of vitamin D supplementation on mitochondrial function in obese subjects.

Conclusions

Vitamin D supplementation affects gene expression in obese, but not in normal-weight subjects. The altered genes are enriched in pathways related to mitochondrial function. The present study increases the understanding of the effects of vitamin D at the transcriptome level.

Open access
Kevin D Cashman Cork Centre for Vitamin D and Nutrition Research, School of Food and Nutritional Sciences, University College Cork, Cork, Ireland

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Background

Internationally, concern has been repeatedly raised about the little notable progress in the collection, analysis and use of population micronutrient status and deficiency data globally. The need for representative status and intake data for vitamin D has been highlighted as a research priority for well over a decade.

Aim and methods

A narrative review which aims to provide a summary and assessment of vitamin D nutritional status data globally. This review divides the world into the Food and Agriculture Organisation’s (FAO) major regions: the Americas, Europe, Oceania, Africa and Asia. Emphasis was placed on published data on the prevalence of serum 25-hydroxyvitamin D (25(OH)D) < 25/30 and <50 nmol/L (reflecting vitamin D deficiency and inadequacy, respectively) as well as vitamin D intake, where possible from nationally representative surveys.

Results

Collating data from the limited number of available representative surveys from individual countries might suggest a relatively low overall prevalence of vitamin D deficiency in South America, Oceania and North America, whereas there is more moderate prevalence in Europe and Asia, and possibly Africa. Overall, the prevalence of serum 25(OH)D < 25/30 and <50 nmol/L ranges from ~5 to 18% and 24 to 49%, respectively, depending on FAO world region. Usual intakes of vitamin D can also vary by FAO world region, but in general, with a few exceptions, there are very high levels of inadequacy of vitamin D intake.

Conclusions

While the burden of vitamin D deficiency and inadequacy varies by world regions and not just by UVB availability, the global burden overall translates into enormous numbers of individuals at risk.

Open access
Amarjit Saini Division of Clinical Physiology, Department of Laboratory Medicine, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden
Unit of Clinical Physiology, Karolinska University Hospital, Stockholm, Sweden

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Linda Björkhem-Bergman Division of Clinical Geriatrics, Departments of Neurobiology, Care Sciences and Neurobiology, Karolinska Institutet, Stockholm, Sweden

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Johan Boström Division of Clinical Physiology, Department of Laboratory Medicine, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden
Unit of Clinical Physiology, Karolinska University Hospital, Stockholm, Sweden

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Mats Lilja Division of Clinical Physiology, Department of Laboratory Medicine, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden
Unit of Clinical Physiology, Karolinska University Hospital, Stockholm, Sweden

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Michael Melin Division of Clinical Physiology, Department of Laboratory Medicine, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden
Unit of Clinical Physiology, Karolinska University Hospital, Stockholm, Sweden
Unit of Cardiology, Karolinska University Hospital, Stockholm, Sweden

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Karl Olsson Division of Clinical Physiology, Department of Laboratory Medicine, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden
Unit of Clinical Physiology, Karolinska University Hospital, Stockholm, Sweden

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Lena Ekström Division of Clinical Pharmacology, Department of Laboratory Medicine, Karolinska Institutet, Stockholm, Sweden

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Peter Bergman Division of Clinical Microbiology, Department of Laboratory Medicine, Karolinska Institutet, Stockholm, Sweden

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Mikael Altun Division of Clinical Physiology, Department of Laboratory Medicine, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden
Unit of Clinical Physiology, Karolinska University Hospital, Stockholm, Sweden

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Eric Rullman Division of Clinical Physiology, Department of Laboratory Medicine, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden
Unit of Clinical Physiology, Karolinska University Hospital, Stockholm, Sweden
Unit of Cardiology, Karolinska University Hospital, Stockholm, Sweden

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Thomas Gustafsson Division of Clinical Physiology, Department of Laboratory Medicine, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden
Unit of Clinical Physiology, Karolinska University Hospital, Stockholm, Sweden

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The CC genotype of the vitamin D receptor (VDR) polymorphism TaqI rs731236 has previously been associated with a higher risk of developing myopathy compared to TT carriers. However, the mechanistic role of this polymorphism in skeletal muscle is not well defined. The effects of vitamin D on patients genotyped for the VDR polymorphism TaqI rs731236, comparing CC and TT carriers were evaluated. Primary human myoblasts isolated from 4 CC carriers were compared with myoblasts isolated from four TT carriers and treated with vitamin D in vitro. A dose-dependent inhibitory effect on myoblast proliferation and differentiation was observed concurrent with modifications of key myogenic regulatory factors. RNA sequencing revealed a vitamin D dose–response gene signature enriched with a higher number of VDR-responsive elements (VDREs) per gene. Interestingly, the greater the expression of muscle differentiation markers in myoblasts, the more pronounced was the vitamin D-mediated response to suppress genes associated with myogenic fusion and myotube formation. This novel finding provides a mechanistic explanation to the inconsistency regarding previous reports of the role of vitamin D in myoblast differentiation. No effects in myoblast proliferation, differentiation or gene expression were related to CC vs TT carriers. Our findings suggest that the VDR polymorphism TaqI rs731236 comparing CC vs TT carriers did not influence the effects of vitamin D on primary human myoblasts and that vitamin D inhibits myoblast proliferation and differentiation through key regulators of cell cycle progression. Future studies need to employ strategies to identify the primary responses of vitamin D that drive the cellular response towards quiescence.

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Guido Zavatta Department of Medical and Surgical Sciences, University of Bologna, Bologna, Italy

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Bart L Clarke Mayo Clinic, Rochester, Minnesota, USA

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The first adjunctive hormone therapy for chronic hypoparathyroidism, recombinant human parathyroid hormone (1–84) (rhPTH(1–84)) was approved by the FDA in January 2015. Since the approval of rhPTH(1–84), growing interest has developed in other agents to treat this disorder in both the scientific community and among pharmaceutical companies. For several reasons, conventional therapy with calcium and activated vitamin D supplementation, magnesium supplementation as needed, and occasionally thiazide-type diuretic therapy remains the mainstay of treatment, while endocrinologists and patients are constantly challenged by limitations of conventional treatment. Serum calcium fluctuations, increased urinary calcium, hyperphosphatemia, and a constellation of symptoms that limit mental and physical functioning are frequently associated with conventional therapy. Understanding how conventional treatment and hormone therapy work in terms of pharmacokinetics and pharmacodynamics is key to effectively managing chronic hypoparathyroidism. Multiple questions remain regarding the effectiveness of PTH adjunctive therapy in preventing or slowing the onset and progression of the classical complications of hypoparathyroidism, such as chronic kidney disease, calcium-containing kidney stones, cataracts, or basal ganglia calcification. Several studies point toward an improvement in the quality of life during replacement therapy. This review will discuss current clinical and research challenges posed by treatment of chronic hypoparathyroidism.

Key points:

  • Conventional therapy with calcium and activated forms of vitamin D are currently the mainstays of treatment for most patients with chronic hypoparathyroidism.

  • Hormone therapy can be administered through FDA-approved once-daily rhPTH(1–84), or off-label multiple-daily injections of teriparatide. The former is the only FDA-approved drug, with safety and efficacy supported by a randomized placebo-controlled trial and open-label long-term extension trial data.

  • Twice-daily teriparatide has been used in children safely for up to 10 years.

  • New pharmacological options that replace the deficient hormone wi ll likely be available within the next few years.

Open access
Jennifer K Y Ko Department of Obstetrics and Gynecology, The University of Hong Kong, Hong Kong Special Administrative Region, Hong Kong, China

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Jinghua Shi Department of Obstetrics and Gynecology, Peking Union Medical College Hospital, Beijing, China

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Raymond H W Li Department of Obstetrics and Gynecology, The University of Hong Kong, Hong Kong Special Administrative Region, Hong Kong, China

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William S B Yeung Department of Obstetrics and Gynecology, The University of Hong Kong, Hong Kong Special Administrative Region, Hong Kong, China

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Ernest H Y Ng Department of Obstetrics and Gynecology, The University of Hong Kong, Hong Kong Special Administrative Region, Hong Kong, China

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Objective

Vitamin D receptors are present in the female reproductive tract. Studies on the association between serum vitamin D level and pregnancy rate of in vitro fertilization (IVF) showed inconsistent results and focused on a single fresh or frozen embryo transfer cycle. The objective of our study was to evaluate if serum vitamin D level before ovarian stimulation was associated with the cumulative live birth rate (CLBR) of the first IVF cycle.

Design

Retrospective cohort study.

Methods

Women who underwent the first IVF cycle from 2012 to 2016 at a university-affiliated reproductive medicine center were included. Archived serum samples taken before ovarian stimulation were analyzed for 25(OH)D levels using liquid chromatography-mass spectrometry.

Results

In total, 1113 had pregnancy outcome from the completed IVF cycle. The median age (25th–75th percentile) of the women was 36 (34–38) years and serum 25(OH)D level was 53.4 (41.9–66.6) nmol/L. The prevalence of vitamin D deficiency (less than 50 nmol/L) was 42.2%. The CLBR in the vitamin D-deficient group was significantly lower compared to the non-deficient group (43.9%, 208/474 vs 50.9%, 325/639, P  = 0.021, unadjusted), and after controlling for women’s age, BMI, antral follicle count, type and duration of infertility. There were no differences in the clinical/ongoing pregnancy rate, live birth rate and miscarriage rate in the fresh cycle between the vitamin D deficient and non-deficient groups.

Conclusions

Vitamin D deficiency was prevalent in infertile women in subtropical Hong Kong. The CLBR of the first IVF cycle in the vitamin D-deficient group was significantly lower compared to the non-deficient group.

Open access