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ABSTRACT: BACKGROUND: PAX6 is a transcription factor involved in the regulation of eye and islet cell development in humans and has also been shown to be an early marker of the pituitary gland in mice. While some subjects with PAX6 mutations were found to have impaired glucose tolerance or diabetes in two previous studies, there has been no report of systematic pituitary function assessment in these patients. AIM: The objective of this report was to assess pituitary function and glucose tolerance in five related patients with a heterozygous PAX6 mutation and an unusual ocular and neurological phenotype. SUBJECTS AND METHODS: Pituitary function (static and dynamic exploration of the five ante-pituitary axes) and glucose tolerance (oral glucose tolerance test) were explored in all patients. RESULTS: Glucose tolerance was normal in all patients. We found no obvious pituitary deficiency in four of the five patients. However, borderline cortisol levels were observed in three out of these patients, with subnormal values, at baseline and/or after stimulation test. Basal and stimulated cortisol levels were both more clearly diminished in one subject. CONCLUSIONS: We report here the first complete pituitary function assessment, together with glucose tolerance evaluations, in five related patients with a PAX6 mutation. We cannot rule out subtle corticotrope deficiency induced by PAX6 mutation. The conflicting results with the literature about glucose tolerance could be explained by genotype/phenotype correlations.
Annales d Endocrinologie 11/2012; · 0.74 Impact Factor
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ABSTRACT: The aim of the present study was to assess the efficiency of cell-based immune assays in the detection of alloreactivity after islet transplantation and to correlate these results with clinical outcome. Mixed lymphocyte cultures were performed with peripheral blood mononuclear cells from recipients (n=14), donors or third party. The immune reactivity was assessed by the release of IFNγ (ELISpot), cell proliferation (FACS analysis for Ki67) and cytokine quantification (Bioplex). Islet function correlated with the number of IFNγ-secreting cells following incubation with donor cells (p=0.007, r=-0.50), but not with third party cells(p=0.61). Similarly, a high number of donor-specific proliferating cells was associated with a low islet function (p=0.006, r=-0.51). Proliferating cells were mainly CD3⁺CD4⁺ lymphocytes and CD3-CD56⁺ natural killer cells (with low levels of CD3⁺CD8⁺ lymphocytes). Patients with low islet function had increased levels of CD4⁺Ki67⁺cells (p≤0.0001), while no difference was observed in CD8⁺Ki67⁺ and CD56⁺Ki67⁺ cells. IFNγ, IL-5 and IL-17 levels were increased in patients with low islet function, but IL-10 levels tended to be lower. IFNγ-ELISPOT, proliferation and cytokines were similarly accurate in predicting clinical outcome (AUC=0.77 +/- 0.088, 0.85 +/- 0.084 and 0.88+/- 0.074 respectively). Cellular immune reactivity against donor cells correlates with post-transplant islet function. The tested assays have the potential to be of substantial help in the management of islet graft recipients and deserve prospective validation.
Cell Transplantation 09/2012; · 5.13 Impact Factor
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Thierry Thevenot,
Richard Dorin,
Elisabeth Monnet,
Clifford R Qualls,
Remy Sapin,
Emilie Grandclement, Sophie Borot,
Frances Sheppard,
Delphine Weil,
Thibault Degand,
Vincent Di Martino,
Rasa Kazlauskaite
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ABSTRACT: Background and Aim: We investigated: (i) the association between severity of cirrhosis and serum levels of free cortisol (SFC) and total cortisol (STC), measured before and 30 min after (T(30) ) the low-dose 1-µg short synacthen test (LD-SST); and (ii) the prognostic value of SFC and STC. Methods: Consecutive, hemodynamically stable, cirrhotic patients (34 Child-Pugh class A, 29B, and 32C) underwent the LD-SST. Patients were followed for at least 12 months to assess non-transplant-related mortality. Results: Child-Pugh class C patients had significantly higher basal levels of SFC than Child-Pugh class A or B patients. Prevalence of suspected adrenal dysfunction ranged between 7.4% (T(0) STC < 138 nmol/L) and 49.4% (change in STC < 250 nmol/L) according to the threshold used. In receiver-operator curve analysis, the area-under-the-curve values were 0.67 for T(30) SFC (0.51-0.79), 0.81 for Child-Pugh score (0.70-0.88), and 0.79 for albumin level (0.63-0.88). During the follow-up period, 16 patients with high T(30) SFC (≥ 78.9 nmol/L) (26.2%) and one patient with low T(30) SFC (< 78.9 nmol/L) (3.4%) died (P = 0.027 for high vs low T(30) SFC, log-rank test). Albeit not statistically significant, the risk of death for patients with T(30) SFC ≥ 78.9 nmol/L was fivefold higher than for patients with lower levels after adjusting for cirrhosis severity and level of albumin. Conclusions: One-year, non-transplant-related mortality is high among patients with T(30) levels of SFC ≥ 78.9 nmol/L (26.2%). These findings might result from latent inflammatory stress in hemodynamically stable cirrhotic patients, detected by adrenal testing.
Journal of Gastroenterology and Hepatology 05/2012; 27(10):1596-1601. · 2.87 Impact Factor
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ABSTRACT: The aim of this study was to assess the expression of different types of cadherins in human islets and their role in human β-cell apoptosis. Expression of E-, N-, and P-cadherins was studied by immunofluorescence on pancreas sections and islet cells, and by Western blotting on protein extracts of isolated islets and islet cells. The effects of specific cadherins on cell adhesion and apoptosis were studied using chimeric proteins containing functional E-, N-, or P-cadherin ectodomains fused to Fc fragment of Ig (E-cad/Fc, N-cad/Fc, and P-cad/Fc) and immobilized on glass substrate. β-Cells were identified by immunofluorescence for insulin and apoptotic cells by terminal deoxynucleotide transferase-mediated 2'-deoxyuridine, 5'-triphosphate nick-end labeling. By immunofluorescence, we showed that E- and N-, and not P-, cadherins were expressed at the surface of islet cells. By triple staining, we showed that E-cadherin was expressed at similar extent in β- and α-cells, whereas N-cadherin was preferentially expressed in β-cells. These results were confirmed by Western blot analysis using protein extracts from fluorescence-activated cell sorting-sorted β- and non-β-cells. Adhesion tests showed that the affinity of islet cells for E-cad/Fc and N-cad/Fc and not for P-cad/Fc was increased compared with control. By terminal deoxynucleotide transferase-mediated 2'-deoxyuridine, 5'-triphosphate nick-end labeling, we showed that the percentage of apoptotic cells was lower in aggregated β-cells compared with single β-cells and that attachment to E-cad/Fc and N-cad/Fc and not to P-cad/Fc decreased apoptosis of single β-cells compared with control. Our results show that at least E- and N-cadherins are expressed at the surface of human β-cells and that these adhesion molecules are involved in the maintenance of β-cell viability.
Endocrinology 12/2011; 152(12):4601-9. · 4.46 Impact Factor
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Sophie Borot,
Nadja Niclauss,
Anne Wojtusciszyn,
Coralie Brault,
Sandrine Demuylder-Mischler,
Yannick Müller,
Laurianne Giovannoni,
Géraldine Parnaud,
Raphael Meier,
Lionel Badet, [......],
Laurence Kessler,
Emmanuel Morelon,
Alfred Penfornis,
Charles Thivolet,
Christian Toso,
Philippe Morel,
Domenico Bosco,
Cyrille Colin,
Pierre-Yves Benhamou,
Thierry Berney
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ABSTRACT: Insulin independence after islet transplantation is generally achieved after multiple infusions. However, single infusion would increase the number of recipients. Our aim was to evaluate the results of islet-after-kidney transplantation according to the number of infusions.
Islets were isolated at the Geneva University, shipped, and transplanted into French patients from the Swiss-French GRAGIL network, on the "Edmonton" immunosuppression protocol between 2004 and 2010.
Nineteen patients were transplanted with 33 preparations. Fifteen patients reached 24 months follow-up; eight subjects were single-graft recipients and seven were double-graft recipients. Finally, single-graft recipients received a median of 5312 islet equivalents/kg (5186-6388) vs. 10,564 (10,054-11,375) for double-graft recipients (P=0.0003) with similar islet mass at first infusion. Insulin independence was achieved in five of eight single-graft subjects (62.5%) versus five of seven in double-graft subjects (71.4%), not significant. Median insulin independence duration was 4.7 (3.1-15.2) months after one infusion vs. 19 (9.6-20.8) months after two infusions (not significant). At 24 months posttransplant, comparing single- with double-graft patients, insulin doses were 0.23 (0.11-0.34) U/kg vs. 0.02 (0.0-0.23) U/kg, P=0.11; HbA1c was 6.5% (5.9%-6.8%) vs. 6.2% (5.9%-6.3%), P=0.16; and basal C-peptide was 302 (143-480) pmol/L vs. 599 (393-806) pmol/L, P=0.05. Only 37.5% of single-graft patients had a β-score ≥4 compared with 100% of double-graft patients (P=0.03). Two recipients experienced postinfusion bleeding, and two patients (13%) showed renal dysfunction in the absence of biopsy-proven rejection.
One infusion achieves good glycemic control and sometimes insulin independence. However, double-graft patients remain insulin-free longer, tend to have lower HbA1c, and show better graft function 24 months after transplant.
Transplantation 09/2011; 92(9):1031-8. · 4.00 Impact Factor
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ABSTRACT: Since the Edmonton trials, insulin independence can reproducibly be achieved after islet transplantation. However, a majority of patients resume insulin treatment in the first 5 years after transplantation. Several mechanisms have been proposed but are difficult to pinpoint in one particular patient. Current tools for the metabolic monitoring of islet grafts indicate islet dysfunction when it is too late to take action. Noninvasive imaging of transplanted islets could be used to study β-cell mass and β-cell function just after infusion, during vascularization or autoimmune and alloimmune attacks. This review will focus on the most recent advances in various imaging techniques (bioluminescence imaging, fluorescence optical imaging, MRI, and positron emission tomography). Emphasis will be placed on pertinent approaches for translation to human practice.
Current Diabetes Reports 07/2011; 11(5):375-83. · 2.50 Impact Factor
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Mathurin Baquié,
Luc St-Onge,
Julie Kerr-Conte,
Nadia Cobo-Vuilleumier,
Petra I Lorenzo,
Carmen M Jimenez Moreno,
Christopher R Cederroth,
Serge Nef, Sophie Borot,
Domenico Bosco,
Haiyan Wang,
Piero Marchetti,
Francois Pattou,
Claes B Wollheim,
Benoit R Gauthier
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ABSTRACT: Liver receptor homolog (LRH-1) is an orphan nuclear receptor (NR5A2) that regulates cholesterol homeostasis and cell plasticity in endodermal-derived tissues. Estrogen increases LRH-1 expression conveying cell protection and proliferation. Independently, estrogen also protects isolated human islets against cytokine-induced apoptosis. Herein, we demonstrate that LRH-1 is expressed in islets, including β-cells, and that transcript levels are modulated by 17β-estradiol through the estrogen receptor (ER)α but not ERβ signaling pathway. Repression of LRH-1 by siRNA abrogated the protective effect conveyed by estrogen on rat islets against cytokines. Adenoviral-mediated overexpression of LRH-1 in human islets did not alter proliferation but conferred protection against cytokines and streptozotocin-induced apoptosis. Expression levels of the cell cycle genes cyclin D1 and cyclin E1 as well as the antiapoptotic gene bcl-xl were unaltered in LRH-1 expressing islets. In contrast, the steroidogenic enzymes CYP11A1 and CYP11B1 involved in glucocorticoid biosynthesis were both stimulated in transduced islets. In parallel, graded overexpression of LRH-1 dose-dependently impaired glucose-induced insulin secretion. Our results demonstrate the crucial role of the estrogen target gene nr5a2 in protecting human islets against-stressed-induced apoptosis. We postulate that this effect is mediated through increased glucocorticoid production that blunts the pro-inflammatory response of islets.
Human Molecular Genetics 07/2011; 20(14):2823-33. · 7.64 Impact Factor
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ABSTRACT: Recent technological advancements in insulin administration and glucose monitoring have allowed patients with diabetes to become increasingly involved in their own care. Devices replacing the traditional vial and syringe, such as insulin pens, are gaining popularity and offer simple and convenient insulin administration. Pen devices are associated with improved dose accuracy, reducing the risk of hypo- or hyperglycemia, and are continually being updated with new safety features in order to optimize their performance. In patients for whom glucose variability remains a problem, continuous subcutaneous insulin infusion via an implanted canula or continuous intraperitoneal insulin infusion via an implanted pump is safe and effective when used correctly, although cost can be a limitation. More accurate retrospective and real-time continuous monitoring devices, which can better detect blood glucose excursions, have become standard components of modern-day diabetes management. The most recent devices have sensor-signaling capabilities with wireless data transmission, leading to reduced time delay and more accurate alerts. Ultimately, though, while self-management remains a critical factor in improving glycemic control at present, human error may undermine even the most accurate treatment interventions. A key long-term goal in diabetes management is, therefore, to develop an automated and accurate closed-loop system for blood glucose monitoring and insulin delivery to better reflect the physiological mechanisms of glucose homeostasis and remove the "human" element. This "artificial pancreas" would offer the most innovative intervention for diabetes management and has the potential to considerably reduce the patient's burden of self-care.
Diabetes Technology & Therapeutics 06/2011; 13 Suppl 1:S93-102. · 1.93 Impact Factor
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Thierry Thevenot, Sophie Borot,
Agnès Remy-Martin,
Remy Sapin,
Jean-Paul Cervoni,
Carine Richou,
Claire Vanlemmens,
Denis Cleau,
Emilie Muel,
Anne Minello,
Simona Tirziu,
Alfred Penfornis,
Vincent Di Martino,
Elisabeth Monnet
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ABSTRACT: Because over 90% of serum cortisol is bound to albumin and corticosteroid-binding globulin (CBG), changes in these proteins can affect measures of serum total cortisol levels in cirrhotics without altering serum-free and salivary cortisol concentrations.
We assessed basal (T₀) and post-synacthen (T₆₀) serum total cortisol, serum-free and salivary cortisol in 125 consecutive cirrhotics (95 non-septic and 30 septic patients with a Child>8).
Serum total cortisol levels significantly decreased from the Child A-C non-septic group, as did albumin and CBG levels, with a non-significant rise in serum-free cortisol concentrations. Non-septic patients with low albumin (≤25 g/L) or CBG levels (≤35 mg/L) had lower T₀ serum total cortisol levels than patients with near-normal albumin (303.4 vs. 382.6 nmol/L; P=0.0035) or with normal CBG levels (289.9 vs. 441.4 nmol/L; P<0.0001), respectively, despite similar serum-free cortisol or salivary cortisol concentrations. Subnormal T₆₀ serum total cortisol concentrations (<510.4 nmol/L) were measured in 7.2% of all patients (Child C: 14.5% vs. Child A and B: 0%; P=0.0013) but no patients exhibited symptoms suggesting adrenal insufficiency. Patients with or without subnormal T₆₀ total cortisol had similar T₀ salivary cortisol and serum-free cortisol concentrations. A trend was observed towards high serum-free cortisol concentrations and mortality in multivariate analysis.
Serum total cortisol levels overestimated the prevalence of adrenal dysfunction in cirrhotics with end-stage liver disease. Since serum-free cortisol cannot be measured routinely, salivary cortisol testing could represent a useful approach but needs to be standardized.
Liver international: official journal of the International Association for the Study of the Liver 03/2011; 31(3):425-33. · 3.82 Impact Factor
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ABSTRACT: The functionality of cryopreserved parathyroid autotransplantation (CPAT) has been evaluated in few studies, mostly conducted by experienced single-institution centers that have reported different success rates ranging from 17% to 83%. In France, CPAT are rare and their functionality has never been evaluated. Moreover, French tissue banks are facing an accumulation of ungrafted samples. The aim of our work was to evaluate the implantation rate of cryopreserved parathyroid samples and the functionality of CPAT in a multicenter study.
Data from 9 French tissue banks were analyzed. CPAT functionality was defined as fully functional (normal parathyroid hormone [PTH] and calcium levels without treatment), partially functional (normal PTH levels but need for treatment to maintain normocalcemia), and nonfunctional (low PTH levels and need for treatment). For dialyzed patients, CPAT was considered nonfunctional if the PTH level in the nongrafted arm was less than 20 pg/mL, partially functional if the PTH level was between 20 and 50 pg/mL, and fully functional if the PTH level was between 50 and 300 pg/mL.
The 9 centers had cryopreserved 1376 samples of parathyroid tissue and only 22 (1.6%) had been autografted in 20 patients (65% renal hyperparathyroidism, 20% multiple endocrine neoplasia type 1, 15% "other") by 12 different surgical teams. The median duration of storage was 11.1 months (range, 0.4-28.5). Only 2 autografts (10%) were fully functional, 2 (10%) were partially functional, and 17 (80%) were nonfunctional at 26 months median follow-up.
The reimplantation rate is low, and the functionality of CPAT is less than those published by experienced centers. Logistical and technical problems occurring in less experienced centers are probably the main reasons for nonfunctioning implants. Considering the results of this study, we suggest that cryopreservation of parathyroid glands should be abandoned when not performed in very large experimented centers, that CPAT should be used only for patients with hyperplasic parathyroid tissue, and that tissue samples should be systematically destroyed when patients do not have hypoparathyroidism or after 1 year of storage.
Surgery 02/2010; 147(4):529-35. · 3.10 Impact Factor
