Clinical science Research Institute
Clinical science Research Institute
Al-Daghri N.M.,King Saud University |
Alkharfy K.M.,King Saud University |
Al-Othman A.,King Saud University |
El-Kholie E.,King Saud University |
And 7 more authors.
Cardiovascular Diabetology | Year: 2012
Background: Vitamin D deficiency has been associated with impaired human insulin action, suggesting a role in the pathogenesis of diabetes mellitus type 2 (T2DM). In this prospective interventional study we investigated the effects of vitamin D3 supplementation on the metabolic profiles of Saudi T2DM subjects pre- and post-vitamin D supplementation over an 18-month period.Methods: T2DM Saudi subjects (men, N = 34: Age: 56.6 ± 8.7 yr, BMI, 29.1 ± 3.3 kg/m2; women, N = 58: Age: 51.2 ± 10.6 yr, BMI 34.3 ± 4.9 kg/m2;) were recruited and given 2000 IU vitamin D3 daily for 18 months. Anthropometrics and fasting blood were collected (0, 6, 12, 18 months) to monitor serum 25-hydroxyvitamin D using specific ELISA, and to determine metabolic profiles by standard methods.Results: In all subjects there was a significant increase in mean 25-hydroxyvitamin D levels from baseline (32.2 ± 1.5 nmol/L) to 18 months (54.7 ± 1.5 nmol/L; p < 0.001), as well as serum calcium (baseline = 2.3 ± 0.23 mmol/L vs. 18 months = 2.6 ± 0.1 mmol/L; p = 0.003). A significant decrease in LDL- (baseline = 4.4 ± 0.8 mmol/L vs. 18 months = 3.6 ± 0.8 mmol/L, p < 0.001] and total cholesterol (baseline = 5.4 ± 0.2 mmol/L vs. 18 months = 4.9 ± 0.3 mmol/L, p < 0.001) were noted, as well as a significant improvement in HOMA-β function (p = 0.002). Majority of the improvements elicited were more prominent in women than men.Conclusion: In the Saudi T2DM population receiving oral Vitamin D3 supplementation (2000 IU/day), circulating 25-hydroxyvitamin D levels remained below normal 18 months after the onset of treatment. Yet, this " suboptimal" supplementation significantly improved lipid profile with a favorable change in HDL/LDL ratio, and HOMA-β function, which were more pronounced in T2DM females. © 2012 Al-Daghri et al.; licensee BioMed Central Ltd.
Parker J.,University of Warwick |
Hashmi O.,University of Warwick |
Dutton D.,Clinical science Research Institute |
Mavrodaris A.,University of Warwick |
And 4 more authors.
Maturitas | Year: 2010
Cardiometabolic disorders and vitamin D deficiency are becoming increasingly more prevalent across multiple populations. Different studies have suggested a potential association between abnormal vitamin D levels and multiple pathological conditions including cardiovascular diseases and diabetes. We aimed to evaluate the association between vitamin D levels, using 25-hydroxy vitamin D (25OHD) as an indicator of vitamin D status, and the presence of cardiometabolic disorders including cardiovascular disease, diabetes and metabolic syndrome. We performed a systematic review of the current literature on vitamin D and cardiometabolic disorders using the PubMed and Web of Knowledge databases in September 2009. Studies in adults looking at the effect of vitamin D levels on outcomes relating to cardiometabolic disorders were selected. We performed a meta-analysis to assess the risk of developing cardiometabolic disorders comparing the highest and lowest groups of serum 25OHD. From 6130 references we identified 28 studies that met our inclusion criteria, including 99,745 participants. There was moderate variation between the studies in their grouping of 25OHD levels, design and analytical approach. We found that the highest levels of serum 25OHD were associated with a 43% reduction in cardiometabolic disorders [OR 0.57, 95% (CI 0.48-0.68)]. Similar levels were observed, irrespective of the individual cardiometabolic outcome evaluated or study design. High levels of vitamin D among middle-age and elderly populations are associated with a substantial decrease in cardiovascular disease, type 2 diabetes and metabolic syndrome. If the relationship proves to be causal, interventions targeting vitamin D deficiency in adult populations could potentially slow the current epidemics of cardiometabolic disorders. © 2009 Elsevier Ireland Ltd. All rights reserved.
Eastwood J.B.,St George's, University of London |
Kerry S.M.,St George's, University of London |
Plange-Rhule J.,St George's, University of London |
Plange-Rhule J.,Komfo Anokye Teaching Hospital |
And 5 more authors.
Nephrology Dialysis Transplantation | Year: 2010
Background. Equations for estimating glomerular filtration rate (GFR) have not been validated in Sub-Saharan African populations, and data on GFR are few.Methods. GFR by creatinine clearance (Ccr) using 24-hour urine collections and estimated GFR (eGFR) using the four-variable Modification of Diet in Renal Disease (MDRD-4)[creatinine calibrated to isotope dilution mass spectrometry (IDMS) standard], Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) and Cockcroft-Gault equations were obtained in Ghanaians aged 40-75. The population comprised 1013 inhabitants in 12 villages; 944 provided a serum creatinine and two 24-hour urines. The mean weight was 54.4 kg; mean body mass index was 21.1 kg/m2.Results. Mean GFR by Ccr was 84.1 ml/min/1.73 m2; 86.8% of participants had a GFR of ≥60 ml/min/1.73 m 2. Mean MDRD-4 eGFR was 102.3 ml/min/1.73 m2 (difference vs. Ccr, 18.2: 95% CI: 16.8-19.5); when the factor for black race was omitted, the value (mean 84.6 ml/min/1.73 m2) was close to Ccr. Mean CKD-EPI eGFR was 103.1 ml/min/1.73 m2, and 89.4 ml/min/1.73 m2 when the factor for race was omitted. The Cockcroft-Gault equation underestimated GFR compared with Ccr by 9.4 ml/min/1.73 m2 (CI: 8.3-10.6); particularly in older age groups. GFR by Ccr, and eGFR by MDRD-4, CKD-EPI and Cockcroft-Gault showed falls with age: MDRD-4 5.5, Ccr 7.7, CKD-EPI 8.8 and Cockcroft-Gault 11.0 ml/min/1.73 m2/10 years. The percentage of individuals identified with CKD stages 3-5 depended on the method used: MDRD-4 1.6% (7.2 % without factor for black race; CKD-EPI 1.7% (4.7% without factor for black race), Ccr 13.2% and Cockcroft-Gault 21.0%.Conclusions. Mean eGFR by both MDRD-4 and CKD-EPI was considerably higher than GFR by Ccr and Cockcroft-Gault, a difference that may be attributable to leanness. MDRD-4 appeared to underestimate the fall in GFR with age compared with the three other measurements; the fall with CKD-EPI without the adjustment for race was the closest to that of Ccr. An equation tailored specifically to the needs of the lean populations of Africa is urgently needed. For the present, the CKD-EPI equation without the adjustment for black race appears to be the most useful. © The Author 2010.
Kihm L.P.,University of Heidelberg |
Muller-Krebs S.,University of Heidelberg |
Klein J.,University of Heidelberg |
Ehrlich G.,University of Heidelberg |
And 8 more authors.
Journal of the American Society of Nephrology | Year: 2011
Residual renal function and the integrity of the peritoneal membrane contribute to morbidity and mortality among patients treated with peritoneal dialysis. Glucose and its degradation products likely contribute to the deterioration of the remnant kidney and damage to the peritoneum. Benfotiamine decreases glucose-induced tissue damage, suggesting the potential for benefit in peritoneal dialysis. Here, in a model of peritoneal dialysis in uremic rats, treatment with benfotiamine decreased peritoneal fibrosis, markers of inflammation, and neovascularization, resulting in improved characteristics of peritoneal transport. Furthermore, rats treated with benfotiamine exhibited lower expression of advanced glycation endproducts and their receptor in the peritoneum and the kidney, reduced glomerular and tubulointerstitial damage, and less albuminuria. Increased activity of transketolase in tissue and blood contributed to the protective effects of benfotiamine. In primary human peritoneal mesothelial cells, the addition of benfotiamine led to enhanced transketolase activity and decreased expression of advanced glycation endproducts and their receptor. Taken together, these data suggest that benfotiamine protects the peritoneal membrane and remnant kidney in a rat model of peritoneal dialysis and uremia. Copyright © 2011 by the American Society of Nephrology.
Gallos I.D.,University of Oxford |
Sivakumar K.,Clinical science Research Institute |
Kilby M.D.,University of Birmingham |
Coomarasamy A.,University of Birmingham |
And 2 more authors.
BJOG: An International Journal of Obstetrics and Gynaecology | Year: 2013
Background Elevated triglycerides are a feature of the metabolic syndrome, maternal obesity, maternal vasculitis (i.e. systemic lupus erythematosus) and diabetes mellitus. These conditions are all known risk factors for pre-eclampsia. Hypertriglyceridaemia therefore may be associated with pre-eclampsia and indeed this may precede the presence of overt disease. Objective In this study we determine the association between hypertriglyceridaemia and pre-eclampsia in pregnant women. Search strategy We searched MEDLINE, EMBASE, Web of Science, Excerpta Medica Database, ISI Web of Knowledge, Cumulative Index to Nursing and Allied Health Literature, Cochrane Library from inception until June 2012 and reference lists of relevant studies. Selection criteria Two reviewers independently selected studies on pregnant women where triglycerides were measured and women were followed up until the development of pre-eclampsia or selected on the basis of presence of pre-eclampsia and compared with controls. Data collection and analysis We collected and meta-analysed the weighted mean differences (WMDs) of triglyceride levels from individual studies using a random effects model. Main results We found strong evidence from meta-analysis of 24 case-control studies (2720 women) that pre-eclampsia is associated with higher levels of serum triglycerides (WMD 0.78 mmol/l, 95% confidence interval 0.6-0.96, P < 0.00001). This finding is also confirmed in five cohort studies, that recruited 3147 women in the second trimester before the onset of pre-eclampsia, which proves that hypertriglyceridaemia precedes the onset of pre-eclampsia (WMD 0.24 mmol/l, 95% confidence interval 0.13-0.34, P < 0.0001). Author's conclusions Hypertriglyceridaemia is associated with and precedes the onset of pre-eclampsia. Further research should focus on defining the prognostic accuracy of this test to identify women at risk and the beneficial effect of triglyceride-lowering therapies in pregnancy. © 2013 RCOG.
Rafnsson S.B.,University of Edinburgh |
Saravanan P.,Clinical science Research Institute |
Bhopal R.S.,University of Edinburgh |
Yajnik C.S.,Hospital and Research Center
European Journal of Nutrition | Year: 2011
Purpose: To assess the prior hypothesis that low blood vitamin B12, partly through hyperhomocysteinemia and partly through direct effects, increases the risk of cardiovascular diseases and diabetes. As background, we also extracted all-cause mortality from the studies that met our criteria. Methods: A systematic review of prospective cohort studies identified through searching six electronic databases, screening of reference lists, and citation search. Included studies reported data on the association between vitamin B12 blood levels, or other appropriate surrogate biological markers e.g. holotranscobalamin or serum/urine methylmalonic acid, and fatal or non-fatal incident diabetes and cardiovascular events. Results: Seven studies were included. Studies differed regarding the population studied, length of follow-up, study outcomes, and data analysis - a narrative synthesis approach was performed to examine the results. Most studies met few of the quality assessment criteria which were adapted from the Scottish Intercollegiate Guidelines Network (SIGN). Only one high-quality study reported that low B12 increased the risk of incident cerebral ischaemia (RR = 1.76; 95% CI = 1.16-2.68). After controlling for homocysteine, the association persisted although weakened (RR = 1.57; 95% CI = 1.02-2.43), suggesting that the effects of low B12 were only partly mediated by homocysteine. In two studies, higher B12 levels were associated with a greater risk of total mortality (RR = 1.00; 95% CI = 1.00-1.00 and HR = 1.15; 95% CI = 1.08-1.22, respectively) and combined fatal and non-fatal coronary events (RR = 1.00; 95% CI = 1.00-1.00). No association between study outcomes and vitamin B12 levels was found in four other studies. Conclusions: Surprisingly, there is only very limited evidence that vitamin B12 deficiency predisposes to the risk of mortality and morbidity from either cardiovascular diseases or diabetes in adults. Current data do not support vitamin B12 supplementation to reduce the risk of cardiovascular diseases or diabetes. © Springer-Verlag 2010.
Vatish M.,Clinical science Research Institute |
Vatish M.,Yeshiva University |
Steer P.J.,Chelsea and Westminster Hospital |
Blanks A.M.,Clinical science Research Institute |
And 2 more authors.
BJOG: An International Journal of Obstetrics and Gynaecology | Year: 2010
Preterm delivery is the primary cause of neonatal mortality and morbidity worldwide. Labour at term occurs as a culmination of maturational events in both the fetus and maternal uterus. This process exhibits diurnal variation, with the onset of labour being more common at night. We have confirmed that this diurnal variation is present in gestations between 28 and 36 weeks, but is absent below 28 weeks. We hypothesise that this is because before 28 weeks of gestation, the onset of labour may result from a pathological rather than a physiological process. This may have important implications regarding any pharmacological approach to the prevention and/or treatment of very early preterm labour. © RCOG 2010 BJOG An International Journal of Obstetrics and Gynaecology.
Cunningham J.,University College London |
Zehnder D.,Clinical science Research Institute
Kidney International | Year: 2011
Vitamin D compounds have been used successfully to treat secondary hyperparathyroidism for almost three decades. Side effects of increased levels of serum calcium and phosphate and potential complications have increasingly been recognized as problematic, and this has become an even more difficult clinical challenge with the desire to capitalize on some of the pleiotropic effects of vitamin D. Nonclassical nuclear vitamin D receptor (VDR) effects on the cardiovascular system, kidneys, and immune system, with the prospect of improved patient survival, have moved to center stage. Selective vitamin D compounds with minimal effects on mineral metabolism and with maximal cardiovascular and renal benefits are now needed. New vitamin D compounds already in clinical use, which have an improved side-effect profile and differential nonclassical effects compared with calcitriol, are limited to the three licensed pharmaceuticalsparicalcitol, 22-oxacalcitriol, and doxercalciferol. Other compounds are under early development and it is anticipated that these novel therapeutic concepts will result in new vitamin D therapies that will help to reduce the high mortality rate patients with kidney disease experience. © 2011 International Society of Nephrology.
Lim K.,Harvard University |
Lim K.,Clinical science Research Institute |
Lu T.-S.,Harvard University |
Molostvov G.,Clinical science Research Institute |
And 5 more authors.
Circulation | Year: 2012
Background-Klotho is known to function as a cofactor for the phosphatonin, fibroblast growth factor (FGF)-23 at the kidney. FGF-23 levels rise in chronic kidney disease (CKD) despite progression of accelerated vascular calcification. There are currently conflicting data on whether FGF-23 may exhibit direct vasculoprotective effects in CKD. Methods and Results-In this study, we describe for the first time endogenous Klotho expression in human arteries and human aortic smooth muscle cells. We show that CKD is a state of vascular Klotho deficiency promoted by chronic circulating stress factors, including proinflammatory, uremic, and disordered metabolic conditions. Mechanistic studies demonstrated that Klotho knockdown potentiated the development of accelerated calcification through a Runx2 and myocardin-serum response factor- dependent pathway. Klotho knockdown studies further revealed that vascular cells are a Klotho-dependent target tissue for FGF-23. FGF-23 mediated cellular activation of p-ERK, p-AKT, and cellular proliferative effects, which were abrogated following Klotho knockdown. We next showed that vascular Klotho deficiency driven by procalcific stressors could be restored by vitamin D receptor activators, in vitro and further confirmed using human arterial organ cultures from CKD patients, in vivo. Furthermore, restoration of suppressed Klotho expression by vitamin D receptor activators conferred human aortic smooth muscle cells responsive to FGF-23 signaling and unmasked potential anticalcific effects. Conclusions-Chronic metabolic stress factors found in CKD promote vascular Klotho deficiency. Mechanistic studies revealed a bifunctional role for local vascular Klotho, first, as an endogenous inhibitor of vascular calcification and, second, as a cofactor required for vascular FGF-23 signaling. Furthermore, vitamin D receptor activators can restore Klotho expression and unmask FGF-23 anticalcific effects. © 2012 American Heart Association, Inc.
Kuroda K.,Clinical Science Research Institute |
Kuroda K.,Juntendo University |
Venkatakrishnan R.,Clinical Science Research Institute |
James S.,Clinical Science Research Institute |
And 7 more authors.
Journal of Clinical Endocrinology and Metabolism | Year: 2013
Background: Decidualizing human endometrial stromal cells (HESCs) profoundly up-regulate 11β- hydroxysteroid dehydrogenase type 1 (11βHSD1), the enzyme that converts inert cortisone to active cortisol.Wepostulated that the induction of a cortisol gradient upon decidualization of the periimplantation endometrium may impact on the uterine natural killer (uNK) cell population and on local expression of corticosteroid-dependent target genes. Methods: Midluteal endometrial biopsies (n=55) were processed for uNK cell (CD56) analysis and primary HESC cultures. The cultures remained either untreated or were decidualized for 4 or 8 days. A tissue microarray was constructed from endometria with normal (n = 18) and elevated uNK cell (n = 18) scores. An abnormal uNK cell test was defined as greater than 5% CD56+ cells in the subluminal stroma. Results: Increased uNK cell density was associated with lower endometrial expression of 11βHSD1 and mineralocorticoid receptor (MR) but not glucocorticoid receptor in vivo. Elevated uNK cell density also corresponded to impaired induction of key decidual markers (11βHSD1, prolactin, and insulin-like growth factor binding protein-1) and MR-dependent enzymes (dehydrogenase/reductase member 3 and retinol saturase) in differentiating HESC cultures. Increased uNK cell density in vivo was not associated with increased in vitro expression of either IL-15 or IL-11, two cytokines implicated in uNK cell regulation. Conclusions: Elevated levels of uNK cells in the stroma underlying the surface epithelium are associated with inadequate cortisol biosynthesis by resident decidualizing cells and suboptimal induction of key MR-dependent enzymes involved in lipid biogenesis and the retinoid transport pathway. Our observations suggest that uNK cell testing identifies those women at risk of reproductive failure due to relative uterine cortisol deficiency. Copyright © 2013 by The Endocrine Society.