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Open access

Panagiotis Anagnostis, Irene Lambrinoudaki, John C Stevenson, and Dimitrios G Goulis

Cardiovascular disease (CVD) is of major concern in women entering menopause. The changing hormonal milieu predisposes them to increased CVD risk, due to a constellation of risk factors, such as visceral obesity, atherogenic dyslipidemia, dysregulation in glucose homeostasis, non-alcoholic fatty liver disease and arterial hypertension. However, an independent association of menopause per se with increased risk of CVD events has only been proven for early menopause (<45 years). Menopausal hormone therapy (MHT) ameliorates most of the CVD risk factors mentioned above. Transdermal estrogens are the preferable regimen, since they do not increase triglyceride concentrations and they are not associated with increased risk of venous thromboembolic events (VTE). Although administration of MHT should be considered on an individual basis, MHT may reduce CVD morbidity and mortality, if commenced during the early postmenopausal period (<60 years or within ten years since the last menstrual period). In women with premature ovarian insufficiency (POI), MHT should be administered at least until the average age of menopause (50–52 years). MHT is contraindicated in women with a history of VTE and is not currently recommended for the sole purpose of CVD prevention. The risk of breast cancer associated with MHT is generally low and is mainly conferred by the progestogen. Micronized progesterone and dydrogesterone are associated with lower risk compared to other progestogens.

Open access

Alexander A L Jorge, Thomas Edouard, Mohamad Maghnie, Alberto Pietropoli, Nicky Kelepouris, Alicia Romano, Martin Zenker, and Reiko Horikawa

Introduction

Mutations in PTPN11 are associated with Noonan syndrome (NS). Although the effectiveness of growth hormone therapy (GHT) in treating short stature due to NS has been previously demonstrated, the effect of PTPN11 mutation status on the long-term outcomes of GHT remains to be elucidated.

Methods

This analysis included pooled data from the observational American Norditropin Studies: Web-Enabled Research Program (NCT01009905) and the randomized, double-blinded GHLIQUID-4020 clinical trial (NCT01927861). Pediatric patients with clinically diagnosed NS and confirmed PTPN11mutation status were eligible for inclusion. The effectiveness analysis included patients who were GHT-naïve and pre-pubertal at GHT start. Growth outcomes and safety were assessed over 4 years of GHT (Norditropin®, Novo Nordisk A/S).

Results

A total of 69 patients were included in the effectiveness analysis (71% PTPN11 positive). The proportion of females was 32.7 and 30.0% in PTPN11-positive and negative patients, respectively, and mean age at GHT start was 6.4 years in both groups. Using general population reference data, after 4 years of GHT, the mean (s.d.) height SD score (HSDS) was −1.9 (1.1) and −1.7 (0.8) for PTPN11-positive and PTPN11-negative patients, respectively, with no statistical difference observed between groups. The mean (s.d.) change in HSDS at 4 years was +1.3 (0.8) in PTPN11-positive patients and +1.5 (0.7) in PTPN11-negative patients (no significant differences between groups). Safety findings were consistent with previous analyses.

Conclusions

GHT resulted in improved growth outcomes over 4 years in GHT-naïve, pre-pubertal NS patients, irrespective of PTPN11 mutation status.

Open access

Luca Giovanella, Maria Luisa Garo, Domenico Albano, Rainer Görges, and Luca Ceriani

Objective

In patients with differentiated thyroid cancer (DTC), recurrences may occur in up to 20% and may have a fatal outcome in 10% of cases. Thyroglobulin doubling time (Tg-DT) values may contribute to predict response to treatment and disease recurrence in DTC patients. This study aimed to address the following questions: (1) Are Tg-DT values indicative of response to treatments in patients with DTC (i.e. ’treatment monitoring’)?; (2) Is Tg-DT predictive of 2-[18F]fluoro-2-deoxy-d-glucose (2-[18F]FDG) PET/CT in patients with DTC?; (3) Are Tg-DT values predictive of DTC prognosis (i.e. ‘prediction’)?

Design

Systematic review and meta-analysis.

Methods

Methodology was registered in the PROSPERO database (CRD42021257947). A systematic search was carried out in PubMed, Web Of Science, and Scopus from June to August 2021 without time and language restrictions.

Results

Eleven studies were included for a total of 1421 patients. Positive association between Tg-DT < 1 year and recurrence or disease progression was observed. Tg-DT was found to be related with (2-[18F]FDG) PET/CT results in patients with DTC. The area under the curve was 0.86 (95% CI: 0.83–0.89), sensitivity was 0.84 (0.64;0.94), specificity was 0.71 (0.35; 0.92), DOR was 13.1 (3.1; 55.0), LR+ was 2.9 (1.0; 8.1), LR− was 0.22 (0.1; 0.5). For patients with Tg-DT < 1 year (n  = 247), the survival risk ratio was 2.09 (95% CI: 1.49; 2.94).

Conclusions

Tg-DT values are valuable in predicting response to treatment and disease recurrence in patients with DTC, as well as their overall survival. In addition, Tg-DT significantly increases the detection rate of 2-[18F]-FDG PET/CT.

Open access

Yanfei Chen, Mei Li, Binrong Liao, Jingzi Zhong, and Dan Lan

Objective

The objective of this study is to investigate the role of serum irisin level in diagnosis of central precocious puberty (CPP) in girls and its major determinants.

Methods

This study was conducted in 67 girls with CPP, 19 girls with premature thelarche (PT) and 59 normal controls. The major determinants of irisin were assessed by multivariate linear regression (MLR) analysis. Propensity score matching (PSM) analysis was performed to minimize the bias that can result from BMI. A receiver operating characteristic curve was used to obtain the optimal threshold value of irisin.

Results

The girls with CPP and PT had higher irisin levels than controls (P  < 0.05). The optimal cutoff value of irisin levels for predicting CPP was 91.88 ng/mL, with a sensitivity of 70.1% and a specificity of 72.9%. MLR analysis showed that BMI was a predictor of irisin (P  < 0.05). Serum irisin levels remained higher in the CPP girls than the controls with adjustment for BMI (P  < 0.05).

Conclusions

Increased serum irisin levels with CPP suggest that irisin is involved in puberty. However, due to low sensitivity and specificity, irisin level can only be used as an auxiliary indicator rather than a single diagnostic indicator of CPP.

Open access

Zhandong Lei, Yunfei Chen, Jin Wang, Yan Zhang, Wenjuan Shi, Xuejiao Wang, Dehai Xing, Dongxue Li, and Xiangying Jiao

Elucidating the mechanisms of regulation of β-cell proliferation is key to understanding the pathogenesis of diabetes mellitus. Txnip is a tumor suppressor that is upregulated in diabetes and plays an important role in the regulation of insulin sensitivity; however, its potential effect on pancreatic β-cell proliferation remains unclear. Here, we evaluated the role of Txnip in pancreatic β-cell compensatory proliferation by subjecting WT and Txnip knockout (KO) mice to a high-fat diet (HFD). Our results demonstrate that Txnip deficiency improves glucose tolerance and increases insulin sensitivity in HFD-induced obesity. The antidiabetogenic effect of Txnip deficiency was accompanied by increased β-cell proliferation and enhanced β-cell mass expansion. Furthermore, Txnip deficiency modulated the expression of a set of transcription factors with key roles in β-cell proliferation and cell cycle regulation. Txnip KO in HFD mice also led to activated levels of p-PI3K, p-AKT, p-mTOR and p-GSK3β, suggesting that Txnip may act via PI3K/AKT signaling to suppress β-cell proliferation. Thus, our work provides a theoretical basis for Txnip as a new therapeutic target for the treatment of diabetes mellitus.

Open access

Ning Yuan, Jianbin Sun, Xin Zhao, Jing Du, Min Nan, Qiaoling Zhang, and Xiaomei Zhang

Background

Numerous studies have found that subclinical hypothyroidism (SCH) may increase adverse pregnancy outcomes; however, the benefit of levothyroxine (LT4) treatment remains controversial. The 2017 guidelines of the American Thyroid Association weakly recommended LT4 therapy for serum antithyroid peroxidase antibody (TPOAb)-negative women with thyroid-stimulating hormone (TSH) concentrations greater than the pregnancy-specific reference range and below 10.0 mU/L. Therefore, the primary goal of this study was to investigate the correlation between thyroid autoantibody-negative SCH with or without LT4 treatment and adverse pregnancy outcomes.

Methods

We prospectively enrolled 1868 consecutive pregnant women. Finally, 1344 women were involved in the study according to the inclusion and exclusion criteria. Assays for TSH, free thyroxine (FT4), TPOAb, anti-thyroglobulin antibody, and laboratory indicators were performed. The participants were divided into the euthyroid (ET) group (n  = 1250) and the SCH group(n  = 94). The SCH group was further divided into LT4 group (n  = 40) and non-LT4 group(n  = 54). The laboratory indicators and pregnancy outcomes were evaluated during follow-ups.

Results

Maternal age, BMI, parity, and the history of spontaneous abortion did not differ significantly between the ET group and the different SCH groups. There were no significant differences in lipid profile and homocysteine levels between ET and SCH group in the first and third trimester of pregnancy. After adjusting the confounding factors, the non-LT4 group was a risk factor for spontaneous abortion (odds ratio: 3.141, 95% CI: 1.060–9.302). Survival analysis showed that the time of abortion was different between the ET group and SCH group (log-rank P= 0.042). The spontaneous abortion in SCH, especially in non-LT4, group mainly occurred in the first trimester of pregnancy.

Conclusions

Thyroid autoantibody negative-SCH seems to be associated with increased risk of spontaneous abortions during the first trimester of pregnancy. LT4 therapy in this patient population might be beneficial to reduce adverse pregnancy outcomes.

Open access

Johanna Öberg, Rolf Jorde, Yngve Figenschau, Per Medbøe Thorsby, Sandra Rinne Dahl, Anne Winther, and Guri Grimnes

Objective

Combined hormonal contraceptive (CHC) use has been associated with higher total 25-hydroxyvitamin D (25(OH)D) levels. Here, we investigate the relation between CHC use and vitamin D metabolism to elucidate its clinical interpretation.

Methods

The cross-sectional Fit Futures 1 included 1038 adolescents. Here, a subgroup of 182 girls with available 25(OH)D, 1,25-dihydroxyvitamin D (1,25(OH)2D), 24,25-dihydroxyvitamin D (24,25(OH)2D), vitamin D-binding protein (DBP) and measured free 25(OH)D levels, in addition to parathyroid hormone (PTH) and fibroblast growth factor 23 (FGF23), was investigated. Vitamin D metabolites were compared between girls using (CHC+) and not using CHC (CHC−). Further, the predictability of CHC on 25(OH)D levels was assessed in a multiple regression model including lifestyle factors. The ratios 1,25(OH)2D/25(OH)D and 24,25(OH)2D/25(OH)D (vitamin D metabolite ratio (VMR)) in relation to 25(OH)D were presented in scatterplots.

Results

CHC+ (n  = 64; 35% of the girls) had higher 25(OH)D levels (mean ± s.d., 60.3 ± 22.2) nmol/L) than CHC- (n  = 118; 41.8 ± 19.3 nmol/L), P -values <0.01. The differences in 25(OH)D levels between CHC+ and CHC− were attenuated but remained significant after the adjustment of lifestyle factors. CHC+ also had higher levels of 1,25(OH)2D, 24,25(OH)2D, DBP and calcium than CHC−, whereas 1,25(OH)2D/25(OH)D, PTH, FGF23 and albumin were significantly lower. Free 25(OH)D and VMR did not statistically differ, and both ratios appeared similar in relation to 25(OH)D, irrespective of CHC status.

Conclusion

This confirms a clinical impact of CHC on vitamin D levels in adolescents. Our observations are likely due to an increased DBP-concentration, whereas the free 25(OH)D appears unaltered.

Open access

Gabriella Oliveira Lima, Alex Luiz Menezes da Silva, Julianne Elba Cunha Azevedo, Chirlene Pinheiro Nascimento, Luana Rodrigues Vieira, Akira Otake Hamoy, Luan Oliveira Ferreira, Verônica Regina Lobato Oliveira Bahia, Nilton Akio Muto, Dielly Catrina Favacho Lopes, and Moisés Hamoy

Low plasma levels of vitamin D causes bone mineral change that can precipitate osteopenia and osteoporosis and could aggravate autoimmune diseases, hypertension and diabetes. The demand for vitamin D supplementation becomes necessary; however, the consumption of vitamin D is not without risks, which its toxicity could have potentially serious consequences related to hypervitaminosis D, such as hypercalcemia and cerebral alterations. Thus, the present study describes the electroencephalographic changes caused by supraphysiological doses of vitamin D in the brain electrical dynamics and the electrocardiographic changes. After 4 days of treatment with vitamin D at a dose of 25,000 IU/kg, the serum calcium levels found were increased in comparison with the control group. The electrocorticogram analysis found a reduction in wave activity in the delta, theta, alpha and beta frequency bands. For ECG was observed changes with shortened QT follow-up, which could be related to serum calcium concentration. This study presented important evidence about the cerebral and cardiac alterations caused by high doses of vitamin D, indicating valuable parameters in the screening and decision-making process for diagnosing patients with symptoms suggestive of intoxication.

Open access

Maria Luisa Brandi, Stefania Bandinelli, Teresa Iantomasi, Francesca Giusti, Eleonora Talluri, Giovanna Sini, Fabrizio Nannipieri, Santina Battaglia, Riccardo Giusti, Colin Gerard Egan, and Luigi Ferrucci

Objective

This study aimed to evaluate the association between the endocrine-disrupting chemical, bisphenol A (BPA) on circulating levels of 25-hydroxy vitamin D (25(OD)D) and other vitamin D metabolites in an elderly population in Italy.

Methods

This was a retrospective analysis of the InCHIANTI Biobank in Italy. The association between vitamin D metabolites namely 1,25(OH)D, 25(OH)D, parathyroid hormone (PTH) and BPA levels were evaluated. Multiple regression models were used to examine the association between predictor variables with 1,25(OH)D or 25(OH)D levels.

Results

Samples from 299 individuals aged 72.8 ± 15.7 years were examined. Mean levels of BPA, 1,25(OH)D and 25(OH)D were 351.2 ± 511.6 ng/dL, 43.7 ± 16.9 pg/mL and 20.2 ± 12.1 ng/mL, respectively. One hundred eighty individuals (60.2%) were deficient (<20 ng/mL) in 25(OH)D and this population also presented higher BPA levels (527.9 ± 1289.5 ng/dL vs 86.9 ± 116.8 ng/dL, P  < 0.0001). Univariate analysis revealed that BPA levels were negatively correlated with both 1,25(OH)D (r= −0.67, P  < 0.0001) and 25(OH)D (r= −0.69, P  < 0.0001). Multivariate regression revealed that PTH (β: −0.23, 95% CI: −0.34, −0.13, P  < 0.0001) and BPA (β: −0.25, 95% CI: −0.3, −0.19, P  < 0.0001) remained significantly associated with 25(OH)D levels while BPA was also associated with 1,25(OH)D levels (β: −0.19, 95% CI: −0.22, −0.15, P  < 0.0001). Receiver operating characteristic curve analysis showed that a BPA concentration of >113 ng/dL was the best cut-off to predict individuals deficient in 25(OH)D (area under the curve: 0.87, 95% CI: 0.82–0.90, P  < 0.0001).

Conclusion

The strong negative association between BPA and vitamin D in this elderly population warrants further investigation, particularly since this population is already at greatest risk of hypovitaminosis and fracture.

Open access

Jane Fletcher, Emma L Bishop, Stephanie R Harrison, Amelia Swift, Sheldon C Cooper, Sarah K Dimeloe, Karim Raza, and Martin Hewison

Vitamin D has well-documented effects on calcium homeostasis and bone metabolism but recent studies suggest a much broader role for this secosteroid in human health. Key components of the vitamin D system, notably the vitamin D receptor (VDR) and the vitamin D-activating enzyme (1α-hydroxylase), are present in a wide array of tissues, notably macrophages, dendritic cells and T lymphocytes (T cells) from the immune system. Thus, serum 25-hydroxyvitamin D (25D) can be converted to hormonal 1,25-dihydroxyvitamin D (1,25D) within immune cells, and then interact with VDR and promote transcriptional and epigenomic responses in the same or neighbouring cells. These intracrine and paracrine effects of 1,25D have been shown to drive antibacterial or antiviral innate responses, as well as to attenuate inflammatory T cell adaptive immunity. Beyond these mechanistic observations, association studies have reported the correlation between low serum 25D levels and the risk and severity of human immune disorders including autoimmune diseases such as inflammatory bowel disease, multiple sclerosis, type 1 diabetes and rheumatoid arthritis. The proposed explanation for this is that decreased availability of 25D compromises immune cell synthesis of 1,25D leading to impaired innate immunity and over-exuberant inflammatory adaptive immunity. The aim of the current review is to explore the mechanistic basis for immunomodulatory effects of 25D and 1,25D in greater detail with specific emphasis on how vitamin D-deficiency (low serum levels of 25D) may lead to dysregulation of macrophage, dendritic cell and T cell function and increase the risk of inflammatory autoimmune disease.