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2.
Hum Reprod ; 36(10): 2753-2760, 2021 09 18.
Article in English | MEDLINE | ID: mdl-34411251

ABSTRACT

STUDY QUESTION: Is the functional ovarian reserve in transgender men affected by testosterone therapy? SUMMARY ANSWER: Serum anti-Müllerian Hormone (AMH) levels slightly decrease during testosterone treatment but remain within the normal range, suggesting preserved follicular ovarian reserve. WHAT IS KNOWN ALREADY: Few small studies have investigated the impact of gender-affirming treatment on reproduction in transgender men. Conflicting results were reached concerning ovarian morphology and AMH levels in this context. STUDY DESIGN, SIZE, DURATION: The study consisted of two arms. The first arm was a prospective pilot study, which enrolled 56 transgender men (median age 22.5 [interquartile range (IQR)-19-27.7] years), 27 of whom had polycystic ovary syndrome (PCOS), prior to the initiation of gender-affirming testosterone therapy. A structured assessment was conducted prior to, and at 3 and 12 months after treatment initiation. The second arm was a cross-sectional study that comprised 47 transgender men (median age 24 [IQR-20-31] years) who received testosterone for a median duration of 35 [IQR 13-62] months. The main outcome measures were serum AMH and antral follicle count (AFC) as indices of ovarian follicular reserve. PARTICIPANTS/MATERIALS, SETTING, METHODS: The study was conducted at a tertiary center for transgender health. Gender-affirming therapy was administered according to standard practice. AFC was determined by pelvic (abdominal or transvaginal) ultrasound and blood collection for measurements of AMH, testosterone, estradiol, LH and FSH was performed at the designated time-points. MAIN RESULTS AND THE ROLE OF CHANCE: Prospective arm for the entire group we observed a decrease of 0.71 ng/ml in AMH levels between baseline and 12 months (P = 0.01). When expressed in age-specific percentiles, AMH went from the 47.37th to the 40.25th percentile at 12 months (P < 0.001). In a sub-group analysis, a decline of 9.52 points in age-specific percentile was seen in subjects with PCOS (P < 0.001), while no changes were detected in the non-PCOS group. Testosterone treatment did not affect AFC over time in the entire cohort. In the sub-group analysis, a mean decrease of 5.0 follicles was detected between baseline and the 12 months assessment (P = 0.047) only in subjects with PCOS. In the cross-sectional study, AMH inversely correlated with age but not with treatment duration. Notably AMH did not deviate from the 50th age-specific percentile. Finally, four men fathered biological children after being under testosterone treatment for up to 12 years. LIMITATIONS, REASONS FOR CAUTION: The limited sample size of the pilot study should be kept in mind. An additional limitation is the lack of a control group in the prospective study, as each participant served as his own control. Also, roughly 40% of the ultrasound examinations were performed transabdominally, potentially affecting the accuracy of the AFC measurements.As study participants were quite young, our reassuring data may not apply to older transgender men, either because of an age-related decline in ovarian reserve or to possible long-term effects of testosterone therapy. Furthermore, the chances for fertility preservation may be more limited in subjects with PCOS. WIDER IMPLICATIONS OF THE FINDINGS: This is an additional contribution to the emerging evidence that prolonged testosterone treatment may not be a major obstacle to later fertility potential in transgender men desirous of having children. Larger confirmatory studies, and particularly more with reproductive outcome data, are needed for evidence-based fertility counseling prior to treatment initiation in these subjects. STUDY FUNDING/COMPETING INTEREST(S): This study received no funding. The authors have no competing interests to declare. TRIAL REGISTRATION NUMBER: N/A.


Subject(s)
Ovarian Reserve , Transgender Persons , Adult , Anti-Mullerian Hormone/analysis , Child, Preschool , Cross-Sectional Studies , Female , Humans , Ovarian Follicle , Pilot Projects , Prospective Studies , Testosterone/therapeutic use , Young Adult
3.
Endocrine ; 71(2): 357-364, 2021 02.
Article in English | MEDLINE | ID: mdl-33398768

ABSTRACT

Metabolic syndrome (MS) is comprised of a cluster of abnormalities in glucose, lipid, and vascular homeostasis, which is most commonly linked to abdominal obesity. MS heralds increased risk for development of diabetes and is linked to impairment in insulin signaling. Insulin-degrading enzyme (IDE) is one of the mechanisms through which insulin blood levels are maintained. It has been previously suggested that controlling IDE levels could provide yet another potential therapeutic approach in diabetes. Here we aim to investigate whether changes in serum IDE levels correlate with the severity of MS. Using a highly sensitive ELISA assay of active IDE in human serum, we found a strong correlation between circulating IDE levels and circulating levels of triglycerides, insulin, and c-peptide and an inverse correlation with HDL cholesterol (HDLc). Serum IDE levels were higher in MS subjects than in control subjects. Hence, circulating IDE may serve as a tool to identify subjects with abnormal insulin metabolism, possibly those with MS that are at risk to develop diabetes.


Subject(s)
Insulysin , Metabolic Syndrome , C-Peptide , Glucose Tolerance Test , Humans , Insulin
4.
J Intern Med ; 289(6): 851-860, 2021 06.
Article in English | MEDLINE | ID: mdl-33340184

ABSTRACT

BACKGROUND: To compare the predictive value of the circadian syndrome (CircS) and Metabolic syndrome (MetS) for cardiovascular disease. METHOD: We used the data of 9360 Chinese adults aged ≥40 years from the 2011 China Health and Retirement Longitudinal Study (CHARLS). Of the participants, 8253 people were followed in the 2015 survey. MetS was defined using the harmonized criteria. CircS was based on the components of the International Diabetes Federation (IDF) MetS plus short sleep and depression. The cut-off for CircS was set as ≥4. Multivariable logistic regression analysis was used to examine the associations. RESULTS: The prevalence of CircS and MetS was 39.0% and 44.7%. Both MetS and CircS were directly associated with prevalent CVD. The odds ratios for prevalent CVD comparing CircS with MetS, respectively, were 2.83 (95%CI 2.33-3.43) and 2.34 (1.93-2.83) in men, and 2.33 (1.98-2.73) and 1.79 (1.53-2.10) in women. Similar associations were found for incident CVD. The five-year incidence of CVD was 15.1% in CircS and 14.0% in MetS. The number of CircS components has a better predictive power for both prevalent and incident CVD than those of Mets components as indicated by the area under the ROC (AUC). AUC values for CVD in 2011 were higher for CircS than MetS in both men (0.659 (95%CI 0.634-0.684) vs 0.635 (95%CI 0.610-0.661)) and women (0.652 (95%CI 0.632-0.672) vs 0.619 (95%CI 0.599-0.640)). CONCLUSION: The circadian syndrome is a strong and better predictor for CVD than the metabolic syndrome in Chinese adults.


Subject(s)
Cardiovascular Diseases , Chronobiology Disorders/epidemiology , Metabolic Syndrome , Adult , Cardiovascular Diseases/epidemiology , China/epidemiology , Female , Humans , Longitudinal Studies , Male , Metabolic Syndrome/epidemiology , Prevalence , Risk Factors
5.
Ann Burns Fire Disasters ; 33(2): 121-125, 2020 Jun 30.
Article in English | MEDLINE | ID: mdl-32913433

ABSTRACT

The paper describes the presentation and management of patients presenting with crack cocaine induced upper airway injury. The study involved a retrospective clinical series of six patients with crack cocaine induced upper airway injury. Demographics, symptoms, physical exam, flexible laryngoscopy findings, treatment and intervention were recorded. All patients with crack cocaine induced thermal injury presented with mouth or throat pain plus at least one other laryngeal symptom, such as globus sensation, dysphagia or throat tightness. On physical exam, the supraglottis was the most common subsite of endolaryngeal injury. The only statistically significant finding was the number of subsites on initial physical exam and flexible laryngoscopy and need for airway intervention (p = 0.001). Airway intervention was required in one patient, while the remaining patients were closely observed until resolution of symptoms. Upper airway injury should be suspected in patients who present with pain and laryngeal symptoms after smoking crack cocaine.


Nous décrivons la clinique et la prise en charge des patients souffrant de lésions respiratoires supérieures liées à l'usage de Crack, en nous basant sur une série rétrospective de 6 cas. Nous avons colligé la démographie, les signes et symptômes, les données cliniques et endoscopiques ainsi que le traitement. Tous souffraient de douleur bucco- pharyngées et au moins d'un signe laryngé parmi sensation de gonflement, dysphagie ou sensation d'étouffement. Á l'examen, la zone supra- glottique était la plus communément atteinte. Le nombre de zones atteintes corrélait positivement (p = 0,001) à la nécessité d'une intervention sur les voies aériennes, qui n'a cependant été nécessaire que pour 1 patient, les autres ayant été simplement surveillés jusqu'à disparition des symptômes. Une atteinte des voies aériennes supérieures doit être soupçonnée devant un patient se présentant avec des douleurs et des signes laryngés après avoir fumé du crack.

6.
J Intern Med ; 286(2): 181-191, 2019 08.
Article in English | MEDLINE | ID: mdl-31081577

ABSTRACT

The Metabolic Syndrome is a cluster of cardio-metabolic risk factors and comorbidities conveying high risk of both cardiovascular disease and type 2 diabetes. It is responsible for huge socio-economic costs with its resulting morbidity and mortality in most countries. The underlying aetiology of this clustering has been the subject of much debate. More recently, significant interest has focussed on the involvement of the circadian system, a major regulator of almost every aspect of human health and metabolism. The Circadian Syndrome has now been implicated in several chronic diseases including type 2 diabetes and cardiovascular disease. There is now increasing evidence connecting disturbances in circadian rhythm with not only the key components of the Metabolic Syndrome but also its main comorbidities including sleep disturbances, depression, steatohepatitis and cognitive dysfunction. Based on this, we now propose that circadian disruption may be an important underlying aetiological factor for the Metabolic Syndrome and we suggest that it be renamed the 'Circadian Syndrome'. With the increased recognition of the 'Circadian Syndrome', circadian medicine, through the timing of exercise, light exposure, food consumption, dispensing of medications and sleep, is likely to play a much greater role in the maintenance of both individual and population health in the future.


Subject(s)
Circadian Rhythm/physiology , Metabolic Syndrome/physiopathology , Cognition Disorders/physiopathology , Depression/physiopathology , Fatty Liver/physiopathology , Humans , Life Style , Risk Factors , Sleep Disorders, Circadian Rhythm/physiopathology
7.
Eur J Surg Oncol ; 45(9): 1660-1667, 2019 Sep.
Article in English | MEDLINE | ID: mdl-31014988

ABSTRACT

BACKGROUND: Primary hepatobiliary cancer incidence in the UK is rising and survival rates are low. Surgery is the main curative option for these cancers, but multimodality therapies are expanding. The aim of our original study was to determine trends in survival, over an 8-year period, of patients treated for primary hepatobiliary cancers at our tertiary referral Centre. METHOD: Patients treated for the most common types of primary hepatobiliary cancers, namely Hepatocellular carcinoma (HCC), Cholangiocarcinoma and Gallbladder cancer between January 2009 and December 2016 were retrospectively analysed from a prospective database linked to UK Hospital Episode Statistics data. RESULTS: A total of 1536 patients with primary hepatobiliary cancers were assessed and treatment plans formulated at our supra-regional specialist Hepatobiliary MDT. The primary hepatobiliary cancers treated were HCC (n = 836), Cholangiocarcinoma (n = 516), and Gallbladder cancer (n = 184). Survival for all the 3 cancers was significantly better with curative treatment. Overall median survival times were 350, 180, and 150 days respectively for HCC, Cholangiocarcinoma and Gallbladder cancer. Excluding best supportive care patients, the respective survival figures were 900, 600, and 400 days. Survival for HCC patients improved over time and was significantly increased in the final 3 years of the study (p ≤ 0.011 for all). Cholangiocarcinoma and Gallbladder cancer survivals were poor and did not change significantly over time. CONCLUSION: HCC outcome has improved in association with expanded multimodal therapies. Survivals for cholangiocarcinoma and gallbladder cancer remain poor in parallel with limited expansion of multimodal therapies highlighting an unmet therapeutic need for biliary tract cancers.


Subject(s)
Biliary Tract Neoplasms/mortality , Biliary Tract Neoplasms/therapy , Carcinoma, Hepatocellular/mortality , Carcinoma, Hepatocellular/therapy , Liver Neoplasms/mortality , Liver Neoplasms/therapy , Adolescent , Adult , Aged , Aged, 80 and over , Combined Modality Therapy , Female , Humans , Male , Middle Aged , Registries , Retrospective Studies , Survival Rate , United Kingdom
8.
Endocr Connect ; 6(8): 847-855, 2017 Nov.
Article in English | MEDLINE | ID: mdl-29038331

ABSTRACT

Ghrelin plasma concentration increases in parallel to cortisol after a standardized psychological stress in humans, but the physiological basis of this interaction is unknown. We aimed to elucidate this question by studying the ghrelin response to pharmacological manipulation of the hypothalamic-pituitary-adrenal (HPA) axis. Six lean, healthy male volunteers were examined under four experimental conditions. Blood samples were collected every 30 min for two sequential periods of two hours. Initially, a baseline period was followed by intravenous injection of a synthetic analog of ACTH (250 µg). Subsequently, a single dose of metyrapone was administered at midnight and in the following morning, blood samples were collected for 2 h, followed by an intravenous injection of hydrocortisone (100 mg) with continued sampling. We show that increased cortisol serum levels secondary to ACTH stimulation or hydrocortisone administration are positively associated with plasma ghrelin levels, whereas central stimulation of the HPA axis by blocking cortisol synthesis with metyrapone is associated with decreased plasma ghrelin levels. Collectively, this suggests that HPA-axis-mediated elevations in ghrelin plasma concentration require increased peripheral cortisol levels, independent of central elevation of ACTH and possibly CRH levels.

9.
Opt Express ; 25(14): 15868-15889, 2017 Jul 10.
Article in English | MEDLINE | ID: mdl-28789099

ABSTRACT

Ring resonators provide a means of filtering specific wavelengths from a waveguide, and optionally dropping the filtered wavelengths into a second waveguide. Both of these features are potentially useful for astronomical instruments. In this paper we focus on their use as notch filters to remove the signal from atmospheric OH emission lines from astronomical spectra. We derive the design requirements for ring resonators for OH suppression from theory and finite difference time domain simulations. We find that rings with small radii (< 10 µm) are required to provide an adequate free spectral range, leading to high index contrast materials such as Si and Si3N4. Critically coupled rings with high self-coupling coefficients should provide the necessary Q factors, suppression depth, and throughput for efficient OH suppression, but will require post-inscription tuning of the coupling and the resonant wavelengths. The overall prospects for the use of ring resonators in astronomical instruments is promising, provided efficient fibre-chip coupling can be achieved.

10.
Aliment Pharmacol Ther ; 45(9): 1232-1243, 2017 05.
Article in English | MEDLINE | ID: mdl-28252210

ABSTRACT

BACKGROUND: Ustekinumab is a monoclonal antibody targeting interleukins-12 and -23, with efficacy in Crohn's disease (CD) demonstrated in clinical trials. AIM: To assess the real-world clinical, endoscopic and radiographic response and remission outcomes achieved with ustekinumab in medically-refractory CD. METHODS: A retrospective multicentre cohort study was performed on CD patients receiving ustekinumab between 2011 and 2016. The primary outcome was achievement of clinical and objective steroid-free response and remission at 3, 6 and 12 months. Clinical response and remission were defined by reduction in Harvey Bradshaw Index (HBI) of ≥3 points and an HBI ≤4 points respectively. Objective response was defined by improvement in endoscopic or radiographic CD, as assessed by ileocolonoscopy, contrast-enhanced ultrasound or CT/MR enterography. Objective remission was defined by endoscopic mucosal healing or complete resolution of inflammatory parameters on radiographic assessment. RESULTS: A total of 167 CD patients were treated with ustekinumab. 95.2% (159/167) previously failed anti-TNF therapy. Median follow-up was 45.6 weeks (IQR: 24.4-88.9). At 3 months, clinical response was achieved in 38.9% (65/167) and remission in 15.0% (25/167) of patients. At 6 months, clinical response was achieved in 60.3% (91/151) and remission in 25.2% (38/151) of patients. At 12 months, clinical response was achieved in 59.5% (66/111) and remission in 27.9% (31/111) of patients. Endoscopic or radiographic response was demonstrated in 54.5% (67/123) at 6 months and 55.8% (48/86) of patients at 12 months. CONCLUSIONS: Ustekinumab is an effective therapeutic option for inducing and maintaining clinical, endoscopic and radiographic response in patients with Crohn's disease failing anti-TNF therapy.


Subject(s)
Crohn Disease/drug therapy , Ustekinumab/therapeutic use , Adult , Colonoscopy , Crohn Disease/diagnostic imaging , Crohn Disease/surgery , Female , Humans , Male , Middle Aged , Retrospective Studies , Tomography, X-Ray Computed , Ultrasonography
11.
J Fish Biol ; 89(5): 2282-2305, 2016 Nov.
Article in English | MEDLINE | ID: mdl-27616166

ABSTRACT

To deal with the difficulties of species differentiation and delimitation among the commercially important sardines from the genus Sardinella, an integrative approach was adopted, incorporating traditional taxonomy with four DNA markers (coI, cytb, 16s and nuclear rag2). Combining these methodologies has enabled a thorough re-description of three of the most common species of Sardinella of the Indo-west Pacific Ocean: white sardinella Sardinella albella, fringescale sardinella Sardinella fimbriata and the goldstripe sardinella Sardinella gibbosa, as well as a description of a new species, Gon's sardinella Sardinella goni, from the island of Boracay, Philippines. In addition, extensive widespread sampling of S. gibbosa reveals a significant genetic separation between the populations from the western Indian Ocean and the west Pacific Ocean, despite no supporting morphological differentiation. An updated morphological key of the species of Sardinella of the Indo-west Pacific Ocean is also provided in order to minimize future misidentifications within these economically important taxa. Finally, the genetic and morphological variabilities within and between the investigated species are used to discuss their biogeographical distribution and possible processes of speciation.


Subject(s)
Fishes/classification , Animals , Fishes/anatomy & histology , Fishes/genetics , Genetic Variation , Indian Ocean , Islands , Pacific Ocean , Philippines , Phylogeny
13.
Eur J Endocrinol ; 175(1): 63-72, 2016 Jul.
Article in English | MEDLINE | ID: mdl-27150495

ABSTRACT

OBJECTIVE: Clinically nonfunctioning pituitary adenoma (NFPA) remains the only pituitary tumor subtype for which no effective medical therapy is available or recommended. We evaluated dopamine agonist (DA) therapy for preventing growth of postsurgical pituitary tumor remnants. DESIGN: The study design included historical cohort analysis of clinical results at two pituitary referral centers with different standard practices for postoperative NFPA management: DA therapy or conservative follow-up. METHODS: Seventy-nine patients followed for 8.8±6.5 years were treated with DA, initiated upon residual tumor detection on postoperative MRI (preventive treatment (PT) group, n=55), or when tumor growth was subsequently detected during follow-up (remedial treatment (RT) group, n=24). The control group (n=60) received no medication. Tumoral dopamine and estrogen receptor expression assessed by quantitative RT-PCR and immunostaining were correlated with response to treatment. RESULTS: Tumor mass decreased, remained stable, or enlarged, respectively, in 38, 49, and 13% of patients in the PT group, and in 0, 53, and 47% of control subjects; shrinkage or stabilization was achieved in 58% of enlarging tumors in the RT group, P < 0.0001.Fifteen-year progression-free survival rate was 0.805, 0.24, and 0.04, respectively, for PT, RT, and control groups (P<0.001). About 42% of patients in the control group required additional surgery or radiotherapy, compared with 38 and 13% subjects in the RT and PT groups, respectively (P=0.002). Outcome measures were not related to NFPA D2R abundance. CONCLUSIONS: Dopamine agonist therapy in patients with NFPA is associated with decreased prevalence of residual tumor enlargement after transsphenoidal surgical resection.


Subject(s)
Adenoma/drug therapy , Bromocriptine/therapeutic use , Dopamine Agonists/therapeutic use , Ergolines/therapeutic use , Pituitary Neoplasms/drug therapy , Adenoma/diagnostic imaging , Adenoma/metabolism , Adult , Aged , Cabergoline , Disease Progression , Female , Humans , Immunohistochemistry , Magnetic Resonance Imaging , Male , Middle Aged , Pituitary Neoplasms/diagnostic imaging , Pituitary Neoplasms/metabolism , Receptors, Dopamine/metabolism , Receptors, Estrogen/metabolism , Treatment Outcome
14.
Frontline Gastroenterol ; 7(2): 82-89, 2016 04.
Article in English | MEDLINE | ID: mdl-28840911

ABSTRACT

OBJECTIVE: Hepatocellular carcinoma (HCC), the sixth most common cancer worldwide and third most common cause of cancer related death, is closely associated with the presence of cirrhosis. Survival is determined by the stage of the cancer, with asymptomatic small tumours being more amenable to treatment. Early diagnosis is dependent on regular surveillance and the primary objective of this survey was to gain a better understanding of the baseline attitudes towards and provision of ultrasound surveillance (USS) HCC surveillance in the UK. In addition, information was obtained on the stages of cancer of the patients being referred to and discussed at regional multidisciplinary team meetings. DESIGN: UK hepatologists, gastroenterologists and nurse specialists were sent a questionnaire survey regarding the provision of USS for detection of HCC in their respective hospitals. RESULTS: Provision of surveillance was poor overall, with many hospitals lacking the necessary mechanisms to make abnormal results, if detected, known to referring clinicians. There was also a lack of standard data collection and in many hospitals basic information on the number of patients with cirrhosis and how many were developing HCC was not known. For the majority of new HCC cases was currently being made only at an incurable late stage (60%). CONCLUSIONS: In the UK, the current provision of USS based HCC surveillance is poor and needs to be upgraded urgently.

16.
J Steroid Biochem Mol Biol ; 148: 210-3, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25448744

ABSTRACT

Estrogen receptors (ERα and ERß), the vitamin D receptor (VDR) and 25 hydroxyy vitamin D 1-α hydroxylase (1OHase) mRNA are expressed in vascular smooth muscle cells (VSMC). In these cells estrogenic hormones modulate cell proliferation as measured by DNA synthesis (DNA). In the present study we determined whether or not the calciotrophic hormones PTH 1-34 (PTH) and less- calcemic vitamin D analog QW as well as hyperglycemia can regulate DNA synthesis and CK. E2 had a bimodal effect on VSMC DNA synthesis, such that proliferation was inhibited at 30nM but stimulated at 0.3nM. PTH at 50nM increased, whereas QW at 10nM inhibited DNA synthesis. Hyperglycemia inhibited the effects on high E2, QW and PTH on DNA only. Both QW and PTH increased ERα mRNA expression, but only PTH increased ERß expression. Likewise, both PTH and QW stimulated VDR and 1OHase expression and activity. ERß, VDR and 1OHase expression and activity were inhibited by hyperglycemia, but ERα expression was unaffected by hyperglycemia. In conclusion, calcitrophic hormones modify VSMC growth and concomitantly affect ER expression in these cells as well as the endogenous VSMC vitamin D system elements, including VDR and 1OHase. Some of the later changes may likely participate in growth effects. Of importance in the observation is that several regulatory effects are deranged in the presence of hyperglycemia, particularly the PTH- and vitamin D-dependent up regulation of VDR and 1OHase in these cells. The implications of these effects require further studies. This article is part of a Special Issue entitled '17th Vitamin D Workshop'.


Subject(s)
25-Hydroxyvitamin D3 1-alpha-Hydroxylase/genetics , Calcitriol/pharmacology , Gene Expression Regulation/drug effects , Hypercalcemia/physiopathology , Muscle, Smooth, Vascular/metabolism , Parathyroid Hormone/pharmacology , RNA, Messenger/genetics , Receptors, Calcitriol/genetics , Animals , Cells, Cultured , Humans , Muscle, Smooth, Vascular/drug effects , Vitamins/pharmacology
17.
J Fish Biol ; 85(2): 394-406, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24976033

ABSTRACT

As part of a comprehensive study of trawl fishery catch off Israel (Ashdod) and Turkey (Iskenderun and Antalya) conducted during 2008-2011, the population explosion of Nemipterus randalli, first recorded in the Mediterranean Sea in the beginning of 2005, was documented. The smallest individuals occurred on deeper bottoms (120 m), significantly more individuals were collected at night, and juvenile recruitment to the commercial fishery occurred during November and December at 40 m depth.


Subject(s)
Fisheries , Perciformes , Animals , Israel , Mediterranean Sea , Turkey
18.
Eur J Clin Nutr ; 68(5): 608-12, 2014 May.
Article in English | MEDLINE | ID: mdl-24619106

ABSTRACT

BACKGROUND/OBJECTIVES: Often recommended, calcium supplements have been incriminated as increasing the risk of cardiovascular events, whereas dietary calcium has generally been exonerated. As a first step to address the vascular safety of such dietary measures at the clinical nutritionist toolbox, we sought to determine and compare the acute effects of a typical oral calcium load, provided either as a supplement or as food, on vascular parameters assessed noninvasively in healthy subjects. SUBJECTS/METHODS: In this acute, cross-over, random-order intervention, 11 young and healthy vitamin D-sufficient volunteers (8 women/3 men, 33±6.1 years, body mass index 22.6±2.3 kg/m(2)), ingested 600 mg of calcium twice, once as calcium citrate and the other time from dairy products. Biochemical, vascular and hemodynamic parameters, before and 2 h after each challenge, were compared. Arterial stiffness was studied by measuring pulse wave velocity, augmentation index and large (C1) and small (C2) arterial compliance. Endothelial function was assessed by flow-mediated dilation (FMD). RESULTS: Despite effective calcium loading accompanied by a significant 60% parathyroid hormone level reduction on both occasions, there were no clinically significant changes in the vascular parameters neither in comparison with baseline, nor between the studies. A decrease in heart rate with no change in cardiac output was noticed after the supplement. CONCLUSIONS: An effective calcium load has no clinically significant untoward effect on the vascular properties of young healthy subjects, regardless of its source. Additional studies should determine whether this holds true for chronic calcium supplementation, particularly in subjects with a priori vascular impairment.


Subject(s)
Arteries/drug effects , Calcium, Dietary/administration & dosage , Dietary Supplements , Endothelium/drug effects , Administration, Oral , Adult , Arteries/metabolism , Calcium, Dietary/adverse effects , Calcium, Dietary/blood , Calcium, Dietary/urine , Creatinine/blood , Creatinine/urine , Cross-Over Studies , Dose-Response Relationship, Drug , Endothelium/metabolism , Female , Healthy Volunteers , Heart Rate/drug effects , Humans , Male , Myocardial Infarction/blood , Myocardial Infarction/etiology , Parathyroid Hormone/blood , Phosphorus/blood , Random Allocation , Recommended Dietary Allowances , Vitamin D/administration & dosage , Young Adult
19.
J Steroid Biochem Mol Biol ; 140: 1-6, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24269661

ABSTRACT

Primary cultures of human bone and vascular cells respond to vitamin D treatment by modulation of cell proliferation measured by DNA synthesis (DNA) and energy metabolism measured by creatine kinase specific activity (CK) via binding to vitamin D receptors (VDR) which are expressed in these cells. Vitamin D compounds also modulate the response to estradiol-17ß (E2) and the expression mRNAs of estrogen receptors (ERα and ERß), VDR, 25-hydroxy vitamin D3 1-α hydroxylase (1OHase) and lipoxygenases (12LO and 15LO). We now compared our newly synthesized analog: 1α,25-dihydroxy-9-methylene-19-norvitamin D3 JK152 (JK), on bone and vascular cells compared to other analogs. Human bone cell line SaOS2 respond to JK by increased DNA and stimulated CK dose-dependently, similar to the less-calcemic analogs CB 1093 (CB) and EB 1089 (EB). JK also up-regulated the response to E2 in terms of DNA and CK. JK inhibited DNA synthesis and increased CK in primary human vascular smooth muscle cells (VSMC) dose-dependently similar to EB and CB. JK up regulated the response to E2 in terms of CK with no effect on DNA. JK similar to CB and EB stimulated mRNA expression of VDR and ERα, 12LO and 15LO, with no effect on ERß and 1OHase mRNA expression in SaOS2 measured by real time PCR. Similar treatments of VSMC with JK, CB and EB stimulated 12LO and 15LO, VDR and ERα mRNA expression with no effect on ERß and 1OHase mRNA expression. The results presented here demonstrate that the new vitamin D less-calcemic analog JK is similar to other analogs in its effects on human cultured cells and therefore may be used in combined hormone replacement treatment (HRT) both in vitro and in vivo.


Subject(s)
Bone and Bones/drug effects , Calcitriol/analogs & derivatives , Muscle, Smooth, Vascular/drug effects , 25-Hydroxyvitamin D3 1-alpha-Hydroxylase/biosynthesis , Arachidonate 12-Lipoxygenase/drug effects , Arachidonate 15-Lipoxygenase/drug effects , Bone and Bones/metabolism , Calcitriol/pharmacology , Cell Line , Cells, Cultured , Creatine Kinase/metabolism , DNA/biosynthesis , DNA/drug effects , Estradiol/pharmacology , Estrogen Receptor alpha/biosynthesis , Humans , Muscle, Smooth, Vascular/cytology , Muscle, Smooth, Vascular/metabolism , RNA, Messenger/metabolism , Receptors, Calcitriol/biosynthesis
20.
Exp Cell Res ; 319(10): 1586-93, 2013 Jun 10.
Article in English | MEDLINE | ID: mdl-23578768

ABSTRACT

Considerable evidence has been published demonstrating the importance of lipoxygenase enzymes for vascular smooth muscle cell (VSMC) growth. The current study sets out to determine whether or not 12-lipoxygenase (12LO) is also important for human placental VSMC survival. Both a pharmacological and two 12LO antisense knockdown approaches were applied. The 12LO inhibitor baicalien induced a 2-2.5-fold increase in cell death, which appeared to result from apoptosis, as indicated by DNA fragmentation, activation of procaspase 3 to caspase 3 and cytochrome C release from the mitochondria to the cytosol. This apoptosis could be prevented by treatment with the 12LO product, 12 hydroxyeicosatetraenoic acid (12HETE). Human platelet-type 12LO-antisense knockdown, by either plasmid transfection or adeno-associated virus (AAV) infection also induced substantial VSMC death over controls, which could also be prevented by treatment with 12HETE, but not 5HETE. Hence, biochemical 12LO inhibition or 12LO-antisense knockdown in VSMC can induce programmed cell death. These observations suggest a previously unrecognized association between human VSMC survivability and 12LO.


Subject(s)
Arachidonate 12-Lipoxygenase/metabolism , Muscle, Smooth, Vascular/cytology , Myocytes, Smooth Muscle/enzymology , 12-Hydroxy-5,8,10,14-eicosatetraenoic Acid/pharmacology , Apoptosis , Arachidonate 12-Lipoxygenase/genetics , Biological Transport , Caspase 3/metabolism , Cell Survival , Cells, Cultured , Cytochromes c/metabolism , DNA, Complementary/genetics , DNA, Complementary/metabolism , Dependovirus/genetics , Dependovirus/metabolism , Flavanones/pharmacology , Gene Knockdown Techniques , Humans , Lipoxygenase Inhibitors/pharmacology , Mitochondria/metabolism , Mitochondrial Proteins/metabolism , Muscle, Smooth, Vascular/enzymology , Plasmids/genetics , Plasmids/metabolism , RNA, Messenger/genetics , RNA, Messenger/metabolism , Transfection
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