Does vitamin D supplementation impact serotonin levels? A systematic review and meta-analysis.

Background and Aims: Vitamin D deficiency impacts a significant proportion of the world's population, and this deficiency has been linked to various conditions characterized by imbalanced serotonin regulation. The objective of this systematic review and meta-analysis was to evaluate the effect of vitamin D supplementation on serum serotonin levels. Methods: We conducted a comprehensive search of PubMed, Scopus, Cochrane Central for Randomized Clinical Trials, and Web of Science up to September 2022, without any language restrictions. The effect sizes were calculated using the standard mean difference (SMD) and 95% confidence interval (CI). Results: Six randomized clinical trials involving 356 participants were included in the analysis. Our findings indicated no significant changes in serotonin levels between the intervention and control groups (SMD: 0.24 ng/mL, 95% CI: -0.28, 0.75, p > 0.10). Subgroup analysis also did not reveal any significant changes in serotonin levels among children, participants with autism spectrum disorders, interventions lasting 10 weeks or longer, or those receiving vitamin D doses below 4000 IU/day. Conclusion: Although the results obtained in this systematic review are inconclusive, they support the need for further well-designed randomized trials to assess the potential role of vitamin D supplementation in regulating serotonin levels and potentially ameliorating depression and related disorders.

Vitamin D Binding Protein (DBP), Free Calcidiol, and Total Calcitriol in Adults from Northern Greece.

Background: An ongoing debate has been raised on whether is better to use total or free calcidiol as a screening test in the population. Methods: In winter and summer, free calcidiol, total calcitriol, and vitamin D binding protein (DBP) concentrations were determined by immunoenzymatic assays in 326 adults (161 males, 165 females). These included 99 osteoporotic patients, 53 type 1 and 51 type 2 diabetics, and 123 athletic healthy persons, all from northern Greece. Results: In the whole sample, free calcidiol mean concentrations differed significantly (p < 0.001) between males (5.53 pg/ml) and females (4.68 pg/ml). Free calcidiol was significantly greater in the athletic healthy group (6.02 pg/ml) than in the three patient groups, and lowest in the osteoporosis group (3.69 pg/ml). Total calcitriol mean concentration did not differ significantly between genders in the whole sample (p = 0.896) or in the study groups, except for type 2 diabetics (males 38.33 pg/ml, females 54.52 pg/ml, p = 0.001). It was significantly less in the osteoporotics (34.61 pg/ml) than in the athletic healthy group (41.65 pg/ml, p = 0.037) and type 1 diabetics (43.73 pg/ml, p = 0.030), whereas it did not differ significantly between the other study groups. The DBP mean concentrations were not significantly different between genders in the whole sample and the study groups nor among the study groups (p = 0.467). Conclusion: Comparisons with our previously reported results of total calcidiol suggest the measurement of free calcidiol offers nothing more than that, and total calcitriol is not a sensitive measure for assessing vitamin D status.

Evaluation of vitamin D in the diagnosis of infants with respiratory distress, the clinical value: A systematic review and meta-analysis.

INTRODUCTION: Respiratory distress (RD) is the most common cause of admission to the Neonatal Intensive Care Unit (NICU). The role of Vitamin D in the development and fortification of fetal pulmonary architecture and the synthesis of surfactants is well-documented. While different serum levels of 25-hydroxyvitamin D (Vit. D) have been studied for their diagnostic significance in RD, there is limited research on how it specifically affects the development of respiratory problems in infants and their mothers. The purpose of the present study is a systematic review and meta-analysis to evaluate the correlation between serum levels of Vit. D in mothers and newborns with RD, and to determine the impact of treating either population on the clinical outcomes of afflicted infants. METHODS: A comprehensive literature search was conducted across various databases, including PubMed, ScienceDirect, Cochrane Library, ISI, and Google Scholar, using a combination of keywords such as RD, diagnosis, vitamin D, mothers, infants, vitamin D supplementation, Respiratory distress syndrome(RDS), and Transient Tachypnea of Newborn (TTN). The search was carried out until March 2024.The level of vitamin D in both mothers and their infants was systematically extracted and analyzed to determine the diagnostic efficacy of Vit. D levels. The mean difference (MD) was calculated along with a 95% confidence interval to determine the association between the Vit. D levels in newborns and their mothers and the likelihood of RD, RDS and TTN in infants. To assess potential publication bias, a funnel plot was generated and Egger's regression test was applied, utilizing a random-effects model. RESULTS: Initially a total of 298 relevant articles was retrieved. Among them, 17 articles with a total of 1,582 infants (745 cases and 837 healthy controls) met the criteria as eligible studies. Of these six were prospective cohort studies, four retrospective case-control studies, four randomized controlled trials (RCTs), and three descriptive-analytical studies. The meta-results revealed a significant association between Vit. D levels and risk of RD in infants (MD = 6.240, 95 %CI: 4.840-7.840, P < 0.001) and mothers (MD = 8.053, 95 %CI: 4.920-11.186, P < 0.001). Furthermore, a strong association was found for risk of RDS (MD = 5.493, 95 %CI: 3.356-7.631, P < 0.001) in infants and TTN (MD = 6.672, 95 %CI: 4.072-9.272, P < 0.001), (MD = 8.595, 95%CI: 4.604-12.586, P < 0.001) both in infants and mothers. Administering 50,000 units of vitamin D to mothers (MD = 8.595, 95 %CI: 4.604-12.586, P < 0.001) prior to childbirth was observed to reduce the likelihood of RD in newborns by 64 % (RR = 0.36, 95 %CI: 0.23-0.57, P < 0.001). Supplemental vitamin D provided to infants was associated with several clinical benefits. CONCLUSION: Our meta-results indicated a significant correlation between serum levels of Vit. D and the risk of RD, RDS and TTN in infants. Prophylactic maternal administration of vitamin D plays a protective role against neonatal RD. Additionally, providing vitamin D to premature infants has shown a significant impact in reducing the incidence of respiratory complications.

Association between serum vitamin D levels and skeletal muscle indices in an older Japanese population: The SONIC study.

AIM: Vitamin D (VD) affects skeletal muscles. The high prevalence of VD deficiency in Japan may lead to decreased skeletal muscle mass and strength, increasing the prevalence of sarcopenia. Therefore, we aimed to investigate the association between serum VD levels and skeletal muscle indices in a Japanese community-dwelling older population. METHODS: We extracted data from the Septuagenarians, Octogenarians, Nonagenarians Investigation with Centenarians (SONIC) study. We analyzed the data for participants in the 70s and 90s age groups. Skeletal mass index (SMI) using bioimpedance analysis, grip strength, walking speed, and serum VD levels using 25-hydroxyvitamin D [25(OH)D] were measured. RESULTS: We analyzed the data of 310 participants in their 70s and 48 in their 90s. Mean serum 25(OH)D levels were 21.6 ± 5.0 ng/mL in the 70s group and 23.4 ± 9.1 ng/mL in the 90s group. In the 70s group, serum 25(OH)D levels correlated with SMI (r = 0.21, P < 0.0001) and grip strength (r = 0.30, P < 0.0001). Serum 25(OH)D levels were independently associated with SMI after adjusting for sex, body mass index, and serum albumin levels. In the 90s group, serum 25(OH)D levels were correlated with SMI (r = 0.29, P = 0.049) and grip strength (r = 0.34, P = 0.018). However, the multivariate analysis showed no independent association between SMI, grip strength, and serum 25(OH)D levels. CONCLUSION: In a cross-sectional analysis of an older population, serum VD levels were associated with SMI and grip strength, and this association was more pronounced in the 70s group than in the 90s group. Our results suggest that serum VD levels maintain skeletal muscle mass and grip strength. Geriatr Gerontol Int 2024; ••: ••-••.

Factors associated with vitamin D deficiency in health care workers exposed to SARS-CoV-2: a cross-sectional study.

Introduction: Globally, up to 76.6% of the population may be affected by vitamin D (VD) deficiency, which has been linked to increased morbidity and mortality from COVID-19. This underscores the importance of further research into VD supplementation, particularly for health care workers, who are at higher risk due to indoor work environments and dietary challenges associated with shift schedules. Objective: This study aimed to identify factors associated with VD deficiency in Mexican health care workers exposed to SARS-CoV-2. Materials and methods: We conducted a cross-sectional study from June 2020 to January 2021 among frontline health care workers treating hospitalized COVID-19 patients. Blood samples were collected to measure 25-hydroxy VD levels via radioimmunoassay. We also assessed previous COVID-19 infection and comorbidities that could influence VD levels. Results: The study included 468 health care workers. The median serum VD concentration was 16.6 ng/mL. VD deficiency was found in 69.4% (n = 325) of participants, while only 5.1% (n = 24) had normal levels. Those with type 2 diabetes (13.3 ng/mL vs. 17.1 ng/mL) or obesity (15.7 ng/mL vs. 17.1 ng/mL) had significantly lower VD levels than their counterparts (p < 0.001 and p = 0.049, respectively). No significant differences were found among participants with high blood pressure. Multivariate analysis revealed that type 2 diabetes was independently associated with VD deficiency. Conclusion: There is a high prevalence of VD deficiency among health care workers, which is potentially linked to both personal health factors and occupational conditions.

Correlation of Parathyroid Hormone Values With Lung Function Parameters in Patients With Chronic Obstructive Pulmonary Disease.

OBJECTIVES: The aim of this study was to determine the disturbances in the concentration of parathyroid hormone (PTH) and 25-hydroxyvitamin D (vitamin D) in patients with stable chronic obstructive pulmonary disease (COPD) and its correlation with airflow obstruction. MATERIALS AND METHODS: A prospective study included 200 patients with a confirmed diagnosis of COPD in the Department of Lung Diseases and Tuberculosis and Pulmonology Polyclinic of University Clinical Hospital Mostar in the period of three years, between May 2021 and May 2024. Inclusion criteria were a stable phase of COPD, hemodynamically stable patients older than 40 years, forced vital capacities in the first second (FEV1)/forced vital capacities (FVC) <0.7, and patients with PTH, vitamin D, calcium, and phosphate measurements. Exclusion criteria were acute exacerbation of COPD in the last month; current treatment with nutritional supplements, vitamins, and statins; lack of availability of lung function data; use of systemic corticosteroids in the previous three months; chronic renal insufficiency, respiratory diseases other than COPD (asthma, pneumonia, tuberculosis, and bronchiectasis), and other diseases (cancer and parathyroid disease). Medical records about demographic data (age and gender), pulmonary function test (FVC, FEV1, FEV1%FVC, mean expiratory flow (MEF)50), body mass index (BMI), COPD assessment test (CAT), Modified Medical Research Council (mMRC) Dyspnea Scale, and serum PTH, vitamin D, calcium, and phosphate levels were obtained. RESULTS:  Patients with higher COPD stage had lower spirometry values, most significantly MEF50. The higher the COPD group (Global Initiative for Chronic Obstructive Lung Disease (GOLD) D), the lower vitamin D ​​and the higher PTH levels were. Calcium and phosphate values ​​were the same for all groups. Vitamin D and PTH levels significantly ​​correlated with MEF50 values. The lower MEF50 level, the higher PTH levels, ​​and lower vitamin D levels were found (P<0.05). CONCLUSION: Our study showed that the patients in the higher COPD group have lower vitamin D levels ​​and higher PTH levels, indicating that they developed secondary hyperparathyroidism. The levels of vitamin D and PTH correlated the most with MEF50 values while other spirometry parameters did not significantly correlate with vitamin D and PTH levels.

Lipids, lipid-modified drug target genes, and the risk of male infertility: a Mendelian randomization study.

Background: Previous observational studies have reported a possible association between circulating lipids and lipid-lowering drugs and male infertility (MIF), as well as the mediating role of circulating vitamin D. Then, due to issues such as bias, reverse causality, and residual confounding, inferring causal relationships from these studies may be challenging. Therefore, this study aims to explore the effects of circulating lipids and lipid-lowering drugs on MIF through Mendelian randomization (MR) analysis and evaluate the mediating role of vitamin D. Method: Genetic variations related to lipid traits and the lipid-lowering effect of lipid modification targets are extracted from the Global Alliance for Lipid Genetics Genome-Wide Association Study. The summary statistics for MIF are from the FinnGen 9th edition. Using quantitative expression feature loci data from relevant organizations to obtain genetic variations related to gene expression level, further to explore the relationship between these target gene expression levels and MIF risk. Two-step MR analysis is used to explore the mediating role of vitamin D. Multiple sensitivity analysis methods (co-localization analysis, Egger intercept test, Cochrane's Q test, pleiotropy residuals and outliers (MR-PRESSO), and the leave-one-out method) are used to demonstrate the reliability of our results. Result: In our study, we observed that lipid modification of four lipid-lowering drug targets was associated with MIF risk, the LDLR activator (equivalent to a 1-SD decrease in LDL-C) (OR=1.94, 95% CI 1.14-3.28, FDR=0.040), LPL activator (equivalent to a 1-SD decrease in TG) (OR=1.86, 95% CI 1.25-2.76, FDR=0.022), and CETP inhibitor (equivalent to a 1-SD increase in HDL-C) (OR=1.28, 95% CI 1.07-1.53, FDR=0.035) were associated with a higher risk of MIF. The HMGCR inhibitor (equivalent to a 1-SD decrease in LDL-C) was associated with a lower risk of MIF (OR=0.38, 95% CI 0.17-0.83, FDR=0.39). Lipid-modifying effects of three targets were partially mediated by serum vitamin D levels. Mediation was 0.035 (LDLR activator), 0.012 (LPL activator), and 0.030 (CETP inhibitor), with mediation ratios of 5.34% (LDLR activator), 1.94% (LPL activator), and 12.2% (CETP inhibitor), respectively. In addition, there was no evidence that lipid properties and lipid modification effects of six other lipid-lowering drug targets were associated with MIF risk. Multiple sensitivity analysis methods revealed insignificant evidence of bias arising from pleiotropy or genetic confounding. Conclusion: This study did not support lipid traits (LDL-C, HDL-C, TG, Apo-A1, and Apo-B) as pathogenic risk factors for MIF. It emphasized that LPL, LDLR, CETP, and HMGCR were promising drug targets for improving male fertility.

Intratumoral vitamin D signaling and lethal prostate cancer.

High circulating vitamin D levels and supplementation may lower prostate cancer mortality. To probe for direct effects of vitamin D signaling in the primary tumor, we assessed how activation of intratumoral vitamin D signaling in prostate cancer is associated with lethal prostate cancer during long-term follow-up. Among 404 participants with primary prostate cancer in the Health Professionals Follow-up Study and the Physicians' Health Study, we defined a gene score of expected activated intratumoral vitamin D signaling consisting of transcriptionally upregulated (CYP27A1, CYP2R1, RXRA, RXRB, VDR) and downregulated genes (CYP24A1, DHCR7). We contrasted vitamin D signaling in tumors that progressed to lethal disease (metastases/prostate cancer-specific death, n = 119) over up to three decades of follow-up with indolent tumors that remained nonmetastatic for >8 years post-diagnosis (n = 285). The gene score was downregulated in tumor tissue compared to tumor-adjacent histologically normal tissue of the same men. Higher vitamin D gene scores were inversely associated with lethal prostate cancer (odds ratio for highest vs. lowest quartile: 0.46, 95% CI: 0.21 to 0.99) in a dose-response fashion and after adjusting for clinical and pathologic factors. This association appeared strongest among men with high predicted plasma 25-hydroxyvitamin D3 and men with body mass index ≥25 kg/m2. Findings were replicated with broader gene sets. These data support the hypothesis that active intratumoral vitamin D signaling is associated with better prostate cancer outcomes and provide further rationale for testing how vitamin D-related interventions after diagnosis could improve prostate cancer survival through effects on the tumor.

A comprehensive investigation of biochemical status in patients with telogen effluvium: Analysis of Hb, ferritin, vitamin B12, vitamin D, thyroid function tests, zinc, copper, biotin, and selenium levels.

AIM: The etiology of telogen effluvium (TE) includes situations that may cause physiological stress, surgical trauma, inflammatory, infectious, iatrogenic causes, medications and nutritional deficiencies. TE has been associated with iron deficiency, vitamin B12 deficiency and thyroid diseases. In recent years, the use of over-the-counter food supplements containing vitamins and minerals such as biotin, vitamin D, zinc (Zn), copper (Cu) and selenium (Se) has been increasing in TE patients. The aim of this study is to investigate whether there are differences in nutritional status, vitamin and mineral levels by comparing individuals with TE and a control group. MATERIALS AND METHODS: This case-control study included 90 female patients diagnosed with chronic telogen effluvium (CTE), and 90 female controls volunteered to participate in the study who consulted for reasons other than TE. Both groups aged 18 and over and applied to dermatology polyclinic between 01.09.2022 and 01.09.2023. A detailed anamnesis was taken from all patients, a hair pull test was performed, and TE was diagnosed after a dermoscopic examination was performed on all areas of the scalp. Then, serum vitamin D, Zn, Cu, Se levels and biotin levels in serum and urine were measured. Hemoglobin (Hb), ferritin, vitamin B12 and thyroid function tests were retrospectively scanned from the hospital database. RESULTS: It was determined that Zn levels were significantly lower in CTE patients than in controls. Se levels were found to be significantly higher in patients than in controls. There was no difference in Hb, ferritin, vitamin B12, thyroid function tests, vitamin D, Cu levels, serum and urine biotin levels between the two groups. Zn, Cu/Zn and Se levels were found to have statistically significant diagnostic performance in predicting the diagnosis of CTE. Cu/Zn ratio and Se value were found to be significant predictors of CTE. CONCLUSION: This study shows us that nutritional deficiencies are not as common as thought in patients diagnosed with TE. Other causes that may cause TE should be investigated by a detailed anamnesis and a good physical examination. After all, tests for suspected conditions should be performed and individualized treatment options should be created for each patient.

Exploring the association between serum Vitamin D levels and the development of coronary artery lesions in Kawasaki disease - a systematic review.

BACKGROUND: Kawasaki Disease (KD) involves arterial inflammation, primarily affecting the coronary arteries and leading to coronary artery lesions. Recent advancements in understanding the immunomodulatory roles of vitamin D have prompted investigations into the potential correlation between serum vitamin D levels and the risk of coronary artery lesions (CAL) in KD. This review aims to explore this association. METHODS: A systematic search utilizing relevant keywords related to Kawasaki disease and coronary artery lesions was conducted across four databases (PubMed, Embase, Scopus, and Web of Science). The quality of the incorporated studies was assessed utilizing the Newcastle-Ottawa Scale. The study protocol is registered in PROSPERO under the registry code CRD42024493204. RESULTS: In a review of five studies involving 442 KD patients and 594 healthy controls, KD patients generally had lower serum vitamin D levels compared to controls, with mixed findings on the association with coronary artery lesions and IVIG resistance. While three studies supported lower vitamin D in KD, one showed no significant difference. Regarding CAL, one study found lower vitamin D, another found higher levels associated with CAL, and two found no significant difference. CONCLUSIONS: Overall, the evidence is inconclusive, but there's a trend suggesting potential benefits of sufficient vitamin D levels in Kawasaki disease rather than evidence refuting any association with clinical outcomes.

General Public Awareness Toward Vitamin D Deficiency in Qassim, Saudi Arabia.

Introduction Vitamin D, essential for various bodily functions, exists as D2 and D3, synthesized from plant and animal sources. Deficiency, linked to reduced intake, sun exposure, or metabolic disorders, poses health risks like diabetes and cardiovascular diseases. Management includes fortification, supplements, and individual assessment to avoid toxicity. Our study aimed to assess the public awareness of vitamin D deficiency in Qassim, Saudi Arabia, examining its relationship with sociodemographic factors. Methodology This cross-sectional study was conducted in the Qassim Region, Saudi Arabia, employing convenient non-probability sampling among a population of 375 individuals. Data collection was facilitated through a validated questionnaire, and subsequent coding, data entry, and analysis were executed using IBM SPSS Statistics for Windows, Version 27.0 (Released 2020; IBM Corp., Armonk, NY, USA). Results Our study included 375 adults in Qassim, Saudi Arabia, revealing varying vitamin D deficiency awareness levels. Most were women (n = 204, 54.4%) residing in urban areas (n = 293, 78.1%). At the same time, 77.6% (n = 291) had prior knowledge of vitamin D and fewer practiced habits conducive to its synthesis, with 47.7% (n = 179) including vitamin D-rich foods and 39.2% (n = 147) exposing themselves to sunlight. Family/friends (n = 99, 26.4%) were the primary information source. Participants scored (n = 183, 48.8%) good or high on vitamin D awareness. Education level (p = 0.028), urban residence (p = 0.001), employment status (p = 0.032), and income (p = 0.001) significantly influenced awareness, and gender, age, and marital status showed no significant associations with vitamin D awareness. Conclusion Our study shows that the majority have prior knowledge of vitamin D, yet significant gaps exist in awareness of vitamin D deficiency among adults in Qassim, Saudi Arabia. Education, urban residence, employment, and income were critical determinants of awareness, underscoring the need for targeted educational interventions. There is a need to provide information about vitamin D and its other aspects through various media, such as television and social platforms.

Knowledge, attitudes and practices (KAP) of medical university students towards vitamin D deficiency in Saudi Arabia: a cross-sectional study.

Introduction: Vitamin D deficiency is a serious health problem that is associated with many health consequences. The study aimed to assess the knowledge, attitudes, and practices of medical students at Qassim University, Saudi Arabia, regarding vitamin D deficiency. Methods: An observational cross-sectional study was conducted among students of Unaizah Colleges of Pharmacy (UCP) and Medicine (UCM) at Qassim University, Saudi Arabia, over a period of 3 months. A well-structured self-administered questionnaire was used for the data collection. Statistical analysis was applied by using SPSS version 22. A 0/1 scoring process was employed to assess the KAP of the participants. The midpoint is considered the cutoff point. Results: A total of 337 complete responses were received. The majority of participants (62.3%) were female. 291 (86.3%) were considered to have good knowledge, with a mean score of 6.326 out of 9. Moreover, 220 (65.2%) of participants had positive attitudes, with a mean score of 4.077 out of 7. Unfortunately, only 9 (2.6%) participants demonstrated satisfactory practices, with a mean score a 0.911 out of 6. Female participants were significantly better than male participants in terms of knowledge and attitudes, but worse in terms of practices. Sun exposure during safe daytime hours is considered the main cause of vitamin D deficiency. Nearly 60% confirmed that KSA indoor activities and the COVID-19 lockdown might maximise vitamin D deficiency. Conclusion: The study reveals a gap in vitamin D knowledge among participants influenced by gender and study year. It suggests educational initiatives for male students to enhance their knowledge regarding vitamin D, while female students are encouraged to prioritise safe sun exposure, minimising the use of umbrellas and sunscreen. It also highlights the role of educational institutions as reliable sources of information and the influence of the COVID-19 pandemic on participants' attitudes and practices towards vitamin D.

Trabecular bone score norms in Asian-Indians and associations with serum 25(OH)D and parathyroid hormone.

OBJECTIVE: There is limited information on population-specific norms of trabecular-bone-score (TBS) and its associated factors. Here, we provide norms of TBS in Asian-Indians and its relationship with serum 25-hydroxyvitamin D [25(OH)D] and intact-parathyroid hormone (iPTH). PARTICIPANTS AND MEASUREMENTS: TBS, bone-mineral-density (BMD), and vertebral-fractures (VFs) were assessed using dual-energy X-ray absorptiometry in 923 healthy Asian-Indians (aged 20-60 years). Serum 25(OH)D, iPTH, T4/TSH,, glycosylated-haemoglobin (HbA1c) were measured and associations with TBS assessed using multivariable linear regression. Subjects with BMD Z-score ≤ -2.0 or ≥2.0 at any sites, VFs, TSH > 10.0 or <0.05 µIU/ml, blood-glucose >11.1 mmol/L or HbA1c > 8.0% were excluded for generating Asian-Indian norms. RESULTS: TBS norms were generated in 744 healthy Asian-Indians (M:F,389:385). The cut-offs generated for 'normal', 'partially-degraded', and 'degraded' TBS were >1.305, 1.204-1.305 and <1.204, respectively. Mean TBS was lower in females than males (p < .001). There was 75% congruency in TBS categories between Asian-Indian and existing norms. Specificity (97.8 vs. 77.9%, p < .001) and diagnostic-accuracy (97.8% vs. 78.4%, p < .001) of TBS to detect osteoporosis were higher with Asian-Indian norms. The sensitivity of 'partially-degraded' TBS to diagnose osteopenia was also higher with Asian-Indian norms. In multivariable regression, gender, body-mass-index (BMI), BMD-L1-L4, serum PTH, daily dietary-calorie intake and calcium intake were associated with TBS. Though 25(OH)D inversely correlated with PTH, 25(OH)D was not associated with TBS. CONCLUSION: This study provides norms for TBS in Asian-Indians with gender-specific differences. Increasing age and higher BMI were associated with lower TBS. Associations of TBS with circulating PTH and/or 25(OH)D need confirmation in further studies.

The Regulatory Effect of Vitamin D on Pancreatic Beta Cell Secretion in Patients with Type 2 Diabetes.

Increasing evidence suggests that vitamin D is one of the causes of accelerated development of Insulin Resistance (IR) and islet cell secret dysfunction. Numerous studies have shown that vitamin D can reduce inflammation, activate the transcription of the insulin receptors and related genes, and increase insulin-mediated glucose transport, thereby reducing IR. This article reviews the molecular mechanisms related to vitamin D deficiency and pancreatic ß-cell dysfunction in patients with Type 2 Diabetes (T2D).

Absence of claudin-3 does not alter intestinal absorption of phosphate in mice.

Intestinal absorption of phosphate is bimodal, consisting of a transcellular pathway and a poorly characterized paracellular mode, even though the latter one contributes to the bulk of absorption under normal dietary conditions. Claudin-3 (Cldn3), a tight junction protein present along the whole intestine in mice, has been proposed to tighten the paracellular pathway for phosphate. The aim of this work was to characterize the phosphate-related phenotype of Cldn3-deficient mice. Cldn3-deficient mice and wildtype littermates were fed standard diet or challenged for 3 days with high dietary phosphate. Feces, urine, blood, intestinal segments and kidneys were collected. Measurements included fecal, urinary, and plasma concentrations of phosphate and calcium, plasma levels of phosphate-regulating hormones, evaluation of trans- and paracellular phosphate transport across jejunum and ileum, and analysis of intestinal phosphate and calcium permeabilities. Fecal and urinary excretion of phosphate as well as its plasma concentration was similar in both genotypes, under standard and high-phosphate diet. However, Cldn3-deficient mice challenged with high dietary phosphate had a reduced urinary calcium excretion and increased plasma levels of calcitriol. Intact FGF23 concentration was also similar in both groups, regardless of the dietary conditions. We found no differences either in intestinal phosphate transport (trans- or paracellular) and phosphate and calcium permeabilities between genotypes. The intestinal expression of claudin-7 remained unaltered in Cldn3-deficient mice. Our data do not provide evidence for a decisive role of Cldn3 for intestinal phosphate absorption and phosphate homeostasis. In addition, our data suggest a novel role of Cldn3 in regulating calcitriol levels.

Association of serum 25-hydroxy vitamin D status with cardiometabolic risk factors and total and regional obesity in southern Iran: evidence from the PoCOsteo study.

Cardiometabolic risk factors increase the chance of developing cardiovascular disease (CVD) and type 2 diabetes. Most CVD risk factors are influenced by total and regional obesity. A higher risk of developing CVD may be linked to vitamin D deficiency, which is more prevalent in the older population. With the goal of evaluating the association between vitamin D and cardiometabolic risk factors and total and regional obesity in older adults, this research included 25 (OH) vitamin D3 concentrations and biochemical markers associated with cardiometabolic diseases, as well as total and regional adiposity, which was measured by DXA. A total of 1991 older participants in the PoCOsteo study were included. Overall, 38.5% of participants had vitamin D deficiency. After adjusting for confounders, the results of multiple linear and logistic regression suggested an inverse association between vitamin D and body mass index (P = 0.04), waist circumference (P = 0.001), total fat (P = 0.02), android fat (P = 0.001), visceral fat (P < 0.001), subcutaneous fat (P = 0.01), trunk fat (P = 0.006), arm fat (P = 0.03), high systolic blood pressure (P = 0.004), high total cholesterol (P < 0.001), high LDL-cholesterol (P < 0.001), high serum triglycerides (P = 0.001), and high fasting glucose (P < 0.001). Additionally, higher vitamin D concentrations decreased the risk of dyslipidemia by 2%. Our results showed a significant association between serum vitamin D and a number of cardiometabolic risk factors, including total and regional obesity.

Clinical value of Vitamin-D combined with budesonide/formoterol and theophylline sodium glycinate sustained-release tablets in the treatment of chronic obstructive pulmonary disease patients.

Objective: To explore the clinical value of Vitamin-D combined with budesonide/formoterol (BF) and theophylline sodium glycinate (TSG) sustained-release tablets in the treatment of patients with chronic obstructive pulmonary disease (COPD). Methods: Medical records of 114 patients with CODP, treated in Wenzhou Geriatric Hospital from October 2020 to February 2023, were retrospectively analyzed. Of them, 59 received treatment with Vitamin-D combined with BF and TSG sustained-release tablets (Group-A), and 55 patients received treatment with BF combined with TSG sustained-release tablets (Group-B). Lung function indicators, blood gas status, inflammatory factors, fractional exhaled nitric oxide (FeNO), and 25-hydroxyvitamin D [25(OH)D] levels before and after the treatment in both groups were collected. Results: After the treatment, lung function indicators, blood gas status, inflammatory factors, FeNO, and 25 (OH) D levels in both groups were significantly improved compared to pretreatment levels, and were significantly better in the Group-A compared to Group-B (P<0.05). Conclusions: The combination of Vitamin-D, BF, and TSG sustained-release tablets can effectively regulate the blood gas status of patients with COPD, improve lung function, regulate FeNO and 25 (OH) D, and effectively downregulate the levels of inflammatory factors, thus reducing the degree of inflammatory response.

Bibliometric analysis of vitamin D and obesity research over the period 2000 to 2023.

Background: Globally, the incidence rates of obesity and its related diseases, such as cardiovascular diseases and type 2 diabetes, are continuously rising, posing a significant public health challenge. Studies have indicated a potential correlation between vitamin D deficiency and obesity. However, a quantitative analysis of the studies related vitamin D and obesity is lacking. This investigation aims to fill this gap by providing a comprehensive bibliometric analysis to uncover the collaborative networks, research hotspots, and evolutionary trends within the field of vitamin D and obesity research. Methods: This study retrieved literature related to vitamin D and obesity from the Web of Science database spanning from 2000 to 2023. Bibliometric analysis was conducted using tools such as HistCite, VOSviewer, and CiteSpace to excavate multi-dimensional information including countries, institutions, authors, journals, citations, and keywords. Results: A total of 6,144 records were retrieved, involving 123 countries, 6,726 institutions, and 28,156 authors, published in 1,551 journals. The number of published papers and citations showed a generally increasing trend. The United States led in terms of publication volume and influence, with journals such as Nutrients and Obesity Surgery having the highest publication counts. Nasser M. Al-Daghri was the most prolific and influential author. Keyword clustering revealed that research topics covered metabolic health, nutrition, immunity, and bariatric surgery. Citation burst analysis indicated a shift in research focus from the relationship between dietary calcium and obesity to the preventive effects of vitamin D supplementation on metabolic diseases. Conclusion: The application of bibliometric methods to analyze the research literature in the fields of obesity and vitamin D has provided a comprehensive understanding of the collaborative networks, key research focus, and evolutionary trends in this field, offering insights for guiding future research directions.

The association of combined vitamin C and D deficiency with bone mineral density and vertebral fracture.

PURPOSE: Both vitamin C and D deficiencies are extremely common in clinical practice, especially in elderly population. Unfortunately, the role of vitamin C deficiency in osteoporosis related consequences is often neglected. The aim of the present study is to analyse if combined vitamin C and D deficiency would have an association with bone mineral density (BMD) and osteoporotic vertebral fracture (OVF). METHODS: Ninety-nine post-menopausal female patients admitted in the department of spine surgery of third affiliated hospital of Sun Yat-sen University were enrolled in the study. The participants were divided into four groups; vitamin D deficiency alone (comparator group), vitamin C deficiency alone and combined vitamin C and D deficiency as experimental group. The levels of vitamin C, vitamin D, calcium, phosphorous, BMD and condition of OVF were analysed. RESULTS: There were statistically significant differences between the groups in terms of vitamin C and D levels. In terms of lumbar BMD, significant differences were observed between vitamin D deficiency alone and combined vitamin C and D deficiency. Only the combined vitamin C and D deficiency had a significant negative association with lumbar BMD and T-score. Similarly, combined vitamin C and D deficiency had a significant positive association with lumbar osteoporosis. None of the groups had any significant association with OVF. Combined vitamin C and D deficiency was found to be significantly associated with lower lumbar BMD and osteoporosis. CONCLUSION: Combined vitamin C and D deficiency results in lower bone mineral density and higher risk of osteoporosis. We believe that existence of deficiencies of both vitamins could have a synergistic effect. Therefore, we recommend that vitamin C and D should be routinely measured in clinical practice.