The Visceral Adiposity Index (VAI) is a sex-specific mathematical index, based on Waist Circumference (WC), Body Mass Index (BMI), triglycerides (TG) and HDL cholesterol (HDL) levels, indirectly ...expressing visceral adipose function and insulin sensitivity. Our aim was to find the optimal cut-off points of VAI identifying a visceral adipose dysfunction (VAD) associated with cardiometabolic risk in a Caucasian Sicilian population.
Medical check-up data of 1,764 Primary Care patients (PC patients) were retrospectively and cross-sectionally examined using a receiver-operating characteristic (ROC) curve to determine appropriate stratified-for-age cut-off of VAI, for the identification of PC patients with Metabolic Syndrome (MetS) according to the NCEP-ATP III criteria. The PC patients with higher VAI scores were subdivided into three groups according to VAI tertiles (i.e. PC patients with mild VAD, moderate VAD or severe VAD). Finally, VAD classes were compared to classical cardio- and cerebrovascular risk factors as independent predictors of coronary heart disease and/or myocardial infarction, transient ischemic attack and/or ischemic stroke.
Moderate and severe VADs proved to be independently associated with cardiovascular events (OR: 5.35; 95% CI: 1.92-14.87; p = 0.001) and (OR: 7.46; 95% CI: 2.64-21.05; p < 0.001) respectively. Mild, moderate and severe VADs were found to be independently associated with cerebrovascular events (OR: 2.73; 95% CI: 1.12-6.65; p = 0.027), (OR: 4.20; 95% CI: 1.86-9.45; p = 0.001) and (OR: 5.10; 95% CI: 2.14-12.17; p < 0.001) respectively.
Our study suggests that among Caucasian Sicilian subjects there are clear cut-off points of VAI able to identify a VAD strongly associated with cardiometabolic risk.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Recent publications suggest that neoplastic initiation and growth are dependent on a small subset of cells, termed cancer stem cells (CSCs). Anaplastic Thyroid Carcinoma (ATC) is a very aggressive ...solid tumor with poor prognosis, characterized by high dedifferentiation. The existence of CSCs might account for the heterogeneity of ATC lesions. CD133 has been identified as a stem cell marker for normal and cancerous tissues, although its biological function remains unknown.
ATC cell lines ARO, KAT-4, KAT-18 and FRO were analyzed for CD133 expression. Flow cytometry showed CD133(pos) cells only in ARO and KAT-4 (64+/-9% and 57+/-12%, respectively). These data were confirmed by qRT-PCR and immunocytochemistry. ARO and KAT-4 were also positive for fetal marker oncofetal fibronectin and negative for thyrocyte-specific differentiating markers thyroglobulin, thyroperoxidase and sodium/iodide symporter. Sorted ARO/CD133(pos) cells exhibited higher proliferation, self-renewal, colony-forming ability in comparison with ARO/CD133(neg). Furthermore, ARO/CD133(pos) showed levels of thyroid transcription factor TTF-1 similar to the fetal thyroid cell line TAD-2, while the expression in ARO/CD133(neg) was negligible. The expression of the stem cell marker OCT-4 detected by RT-PCR and flow cytometry was markedly higher in ARO/CD133(pos) in comparison to ARO/CD133(neg) cells. The stem cell markers c-KIT and THY-1 were negative. Sensitivity to chemotherapy agents was investigated, showing remarkable resistance to chemotherapy-induced apoptosis in ARO/CD133(pos) when compared with ARO/CD133(neg) cells.
We describe CD133(pos) cells in ATC cell lines. ARO/CD133(pos) cells exhibit stem cell-like features--such as high proliferation, self-renewal ability, expression of OCT-4--and are characterized by higher resistance to chemotherapy. The simultaneous positivity for thyroid specific factor TTF-1 and onfFN suggest they might represent putative thyroid cancer stem-like cells. Our in vitro findings might provide new insights for novel therapeutic approaches.
Summary
Background Polycystic ovary syndrome (PCOS) is considered predominantly as a hyperandrogenetic syndrome and the evaluation of metabolic parameters and insulin sensitivity is not mandatory.
...Context PCOS diagnostic criteria National Institute of Health (NIH), Rotterdam Consensus (ROT), Androgen Excess Society (AES) are unanimous recognized. We aimed to assess in women with suspected PCOS whether the application of the three diagnostic criteria differently characterizes the metabolic profile and insulin sensitivity.
Design Retrospective study in a cohort of women admitted to our Outpatient Clinic for suspected PCOS.
Patients Two hundred and four women with suspected PCOS in comparison to a group of normal, age‐matched Sicilian women (N = 34) without signs of metabolic syndrome.
Measurements We evaluated hyperandrogenaemia and clinical hyperandrogenism, ovarian morphology, hypothalamo–hypophyseal axis and metabolic syndrome parameters. An oral glucose tolerance test (OGTT; 75 g glucose) measured areas under the curve (AUC) for insulin, C peptide and homeostasis model assessment of insulin‐resistance (HOMA‐IR) were performed.
Results The prevalence of PCOS was 51% according to NIH, 83% to ROT and 70·6% to AES, and only 100 patients were qualified simultaneously under these three criteria. The prevalence of the metabolic syndrome in PCOS women was 26·92% (NIH), 21·77% (ROT) and 23·61% (AES), respectively. In comparison to healthy women, PCOS women showed increased fasting insulinaemia (PCOS/ROT: P = 0·028; PCOS/NIH: P = 0·007; PCOS/EAS: P = 0·023), 120 min insulin after OGTT insulinaemia (for the three criteria: P < 0·001), AUC2h insulin (for the three criteria: P < 0·001) and AUC2h C peptide (for the three criteria: P < 0·001).
Conclusions Our study highlights the fact that regardless of the diagnostic criteria used, evaluation of the metabolic parameters and insulin sensitivity is important for a correct diagnosis of PCOS and a therapeutic approach.
Type 1 diabetes mellitus (T1DM) is caused by the selective destruction of insulin-producing β-cells. This process is mediated by cells of the immune system through release of nitric oxide, free ...radicals and pro-inflammatory cytokines, which induce a complex network of intracellular signalling cascades, eventually affecting the expression of genes involved in β-cell survival.The aim of our study was to investigate possible mechanisms of resistance to cytokine-induced β-cell death. To this purpose, we created a cytokine-resistant β-cell line (β-TC3R) by chronically treating the β-TC3 murine insulinoma cell line with IL-1β + IFN-γ. β-TC3R cells exhibited higher proliferation rate and resistance to cytokine-mediated cell death in comparison to the parental line. Interestingly, they maintained expression of β-cell specific markers, such as PDX1, NKX6.1, GLUT2 and insulin. The analysis of the secretory function showed that β-TC3R cells have impaired glucose-induced c-peptide release, which however was only moderately reduced after incubation with KCl and tolbutamide. Gene expression analysis showed that β-TC3R cells were characterized by downregulation of IL-1β and IFN-γ receptors and upregulation of SOCS3, the classical negative regulator of cytokines signaling. Comparative proteomic analysis showed specific upregulation of 35 proteins, mainly involved in cell death, stress response and folding. Among them, SUMO4, a negative feedback regulator in NF-kB and JAK/STAT signaling pathways, resulted hyper-expressed. Silencing of SUMO4 was able to restore sensitivity to cytokine-induced cell death in β-TC3R cells, suggesting it may play a key role in acquired cytokine resistance by blocking JAK/STAT and NF-kB lethal signaling.In conclusion, our study represents the first extensive proteomic characterization of a murine cytokine-resistant β-cell line, which might represent a useful tool for studying the mechanisms involved in resistance to cytokine-mediated β-cell death. This knowledge may be of potential benefit for patients with T1DM. In particular, SUMO4 could be used as a therapeutical target.
The mechanisms responsible for thyrocyte destruction in Hashimoto's thyroiditis (HT) are poorly understood. Thyrocytes from HT glands, but not from nonautoimmune thyroids, expressed Fas. ...Interleukin-1β (IL-1β), abundantly produced in HT glands, induced Fas expression in normal thyrocytes, and cross-linking of Fas resulted in massive thyrocyte apoptosis. The ligand for Fas (FasL) was shown to be constitutively expressed both in normal and HT thyrocytes and was able to kill Fas-sensitive targets. Exposure to IL-1β induced thyrocyte apoptosis, which was prevented by antibodies that block Fas, suggesting that IL-1β-induced Fas expression serves as a limiting factor for thyrocyte destruction. Thus, Fas-FasL interactions among HT thyrocytes may contribute to clinical hypothyroidism.
OBJECTIVE: To individuate a novel sex-specific index, based on waist circumference, BMI, triglycerides, and HDL cholesterol, indirectly expressing visceral fat function. RESEARCH DESIGN AND METHODS: ...Visceral adiposity index (VAI) was first modeled on 315 nonobese healthy subjects. Using two multiple logistic regression models, VAI was retrospectively validated in 1,498 primary care patients in comparison to classical cardio- and cerebrovascular risk factors. RESULTS: All components of metabolic syndrome increased significantly across VAI quintiles. VAI was independently associated with both cardiovascular (odd ratio OR 2.45; 95% CI 1.52-3.95; P < 0.001) and cerebrovascular (1.63; 1.06-2.50; P = 0.025) events. VAI also showed significant inverse correlation with insulin sensitivity during euglycemic-hyperinsulinemic clamp in a subgroup of patients (Rs = -0.721; P < 0.001). By contrast, no correlations were found for waist circumference and BMI. CONCLUSIONS: Our study suggests VAI is a valuable indicator of "visceral adipose function" and insulin sensitivity, and its increase is strongly associated with cardiometabolic risk.
Abstract Background: Insulin glargine is a once-daily basal insulin analog with prolonged duration of action and absence of an evident peak. Glargine is associated with reduced frequency of ...hypoglycemic episodes (mostly nocturnal) as well as effective glycemic control. Maintenance of good metabolic control before conception and throughout pregnancy is essential to lower the risk of fetal malformations. Glargine might be a valuable alternative in the management of pregnancies complicated by diabetes mellitus. However, because its clinical utility has not been established, the use of glargine is not currently recommended during pregnancy. Objective: The aim of this study was to retrospectively evaluate (years 2004–2007) the effectiveness and safety of insulin glargine compared with neutral protamine Hagedorn (NPH) in women affected by type 1 diabetes mellitus (T1DM) during pregnancy. Methods: The study comprised pregnant women affected by T1DM who were followed up in the Diabetes and Pregnancy Outpatient Clinic at the University of Palermo, Palermo, Italy, within 8 ± 3.4 weeks subsequent to a positive pregnancy test. All patients with T1DM were treated with conventional basal-bolus insulin therapy (aspart or lispro analogs at the 3 main meals plus glargine or NPH at bedtime). Healthy pregnant women were used as controls for fetal and neonatal parameters. Patients were consecutively enrolled. In all women, metabolic status was determined daily by mean glycemic values (2-hour postprandial blood glucose) and glycosylated hemoglobin (HbA1c) values (at 3-month intervals). Fetal measurements (<50th and >90th centiles of the head circumference, abdomen circumference, and femoral length) were evaluated by ultrasound at second and third trimesters. Weight and femoral length were assessed at birth, and neonates were classified according to the fetal growth curve for the Italian population (<10th centile = small for gestational age; and >90th centile = large for gestational age (LGA). Results: A total of 73 pregnant women (30 with T1DM and 43 healthy control) were included in the study. Of the 30 diabetic pregnant women included in the study, 15 (mean SD age, 27.4 5.2 years; mean pregravidic weight, 59.7 11.7 kg) maintained their preconception therapy with glargine, and 15 (mean age, 30.1 2.4 years; mean pregravidic weight, 60.7 8.7 kg) with NPH. No significant difference was observed between the glargine-treated group and the NPH-treated group with regard to pregravidic hypertension, third-trimester preeclampsia, maternal complications and/or their progression during pregnancy (diabetic retinopathy, micro- or macroalbuminuria) and episodes of mild hypoglycemia, severe hypoglycemia, and ketosis. There were no significant betweengroup differences in insulin requirements (IU/kg of body weight) and glycemic profile, with the exception of better fasting and 2 hours after breakfast glycemic values in the glargine group during the first ( P = 0.008 and P < 0.001, respectively) and the second ( P = 0.015 and P = 0.016) trimesters, confirmed by the lower HbA1c levels in the first trimester ( P = 0.037). The frequency of femoral length <50th centile at both second and third trimesters was 4/15 (26.7%) in the glargine-treated group ( P = 0.033 and P = 0.013, respectively, vs control), 3/15 (20.0%) and 1/15 (6.7%), respectively, in the NPH-treated group (both, P = NS vs control), and 2/43 (4.7%) and 1/43 (2.3%), respectively, in the control group. The prevalence of LGA was 7/15 (46.7%) in the glargine group ( P < 0.001 vs control), 4/15 (27.6%) in the NPH group ( P = 0.033 vs control), and 2/43 (4.7%) in the control group. Conclusions: Although our retrospective study involved only a small number of participants, no significant difference was found in glycemic control between glargine and NPH treatments. Use of glargine was associated with a significantly higher frequency of femoral length <50th centile. Further larger prospective studies are necessary to assess the safety profile of glargine in T1DM during pregnancy.
Stem cells might provide unlimited supply of transplantable cells for β-cell replacement therapy in diabetes. The human limbus is a highly specialized region hosting a well-recognized population of ...epithelial stem cells, which sustain the continuous renewal of the cornea, and the recently identified stromal fibroblast-like stem cells (f-LSCs), with apparent broader plasticity. However, the lack of specific molecular markers for the identification of the multipotent limbal subpopulation has so far limited the investigation of their differentiation potential. In this study we show that the human limbus contains uncommitted cells that could be potentially harnessed for the treatment of diabetes. Fourteen limbal biopsies were obtained from patients undergoing surgery for ocular diseases not involving the conjunctiva or corneal surface. We identified a subpopulation of f-LSCs characterized by robust proliferative capacity, expressing several pluripotent stem cell markers and exhibiting self-renewal ability. We then demonstrated the potential of f-LSCs to differentiate in vitro into functional insulin-secreting cells by developing a four-step differentiation protocol that efficiently directed f-LSCs towards the pancreatic endocrine cell fate. The expression of specific endodermal, pancreatic, islet, and β-cell markers, as well as functional properties of f-LSC-derived insulin-producing cells, were evaluated during differentiation. With our stage-specific approach, up to 77% of f-LSCs eventually differentiated into cells expressing insulin (also assessed as C-peptide) and exhibited phenotypic features of mature β-cells, such as expression of critical transcription factors and presence of secretory granules. Although insulin content was about 160-fold lower than what observed in adult islets, differentiated cells processed ~98% of their proinsulin content, similar to mature β-cells. Moreover, they responded in vitro in a regulated manner to multiple secretory stimuli, including glucose. In conclusion, f-LSCs represent a possible relevant source of autologous, transplantable, insulin-producing cells that could be tested for the reversal of diabetes.
Visceral Adiposity Index Amato, Marco C.; Giordano, Carla; Galia, Massimo ...
Diabetes care,
04/2010, Letnik:
33, Številka:
4
Journal Article
Recenzirano
Odprti dostop
OBJECTIVE
To individuate a novel sex-specific index, based on waist circumference, BMI, triglycerides, and HDL cholesterol, indirectly expressing visceral fat function.
RESEARCH DESIGN AND METHODS
...Visceral adiposity index (VAI) was first modeled on 315 nonobese healthy subjects. Using two multiple logistic regression models, VAI was retrospectively validated in 1,498 primary care patients in comparison to classical cardio- and cerebrovascular risk factors.
RESULTS
All components of metabolic syndrome increased significantly across VAI quintiles. VAI was independently associated with both cardiovascular (odd ratio OR 2.45; 95% CI 1.52–3.95; P < 0.001) and cerebrovascular (1.63; 1.06–2.50; P = 0.025) events. VAI also showed significant inverse correlation with insulin sensitivity during euglycemic-hyperinsulinemic clamp in a subgroup of patients (Rs = −0.721; P < 0.001). By contrast, no correlations were found for waist circumference and BMI.
CONCLUSIONS
Our study suggests VAI is a valuable indicator of “visceral adipose function” and insulin sensitivity, and its increase is strongly associated with cardiometabolic risk.
Visceromegaly is a common consequence of acromegaly. However, few studies investigated the chronic effects of growth hormone on adrenal glands. Our aim was to evaluate adrenal morphology and function ...in a cohort of acromegalic patients in relation to disease activity. Twenty-six acromegalics (10 males and 16 females) and 21 healthy subjects were investigated. Gland morphology was evaluated by computerized axial tomography, measuring central, lateral, and medial adrenal segments. Uncontrolled acromegalics showed increased volume of all adrenal segments, higher urinary free cortisol (UFC), and lower morning adrenocorticotropic hormone in comparison with healthy subjects. However, normal cortisol levels after low-dose dexamethasone suppression test indicated a preserved regulation of the hypothalamic–pituitary–adrenal axis. In addition, uncontrolled patients showed greater medial segment of right gland, higher UFC, and aldosterone levels with respect to controlled patients. All acromegalics did not show any difference in adrenal size when grouped according to UFC/24 h levels. In addition, no difference was found in any of the parameters between normotensive and hypertensive patients. In conclusion, our findings confirm that acromegaly affects adrenal size as well as other organs. In addition, we report a stimulatory effect of growth hormone on adrenal function, although the regulation of the hypothalamic–pituitary–adrenal axis is preserved.