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1.
ESMO Open ; 8(6): 102062, 2023 Dec.
Article En | MEDLINE | ID: mdl-38070434

Cancer management has significantly evolved in recent years, focusing on a multidisciplinary team approach to provide the best possible patient care and address the various comorbidities, toxicities, and complications that may arise during the patient's treatment journey. The co-occurrence of diabetes and cancer presents a significant challenge for health care professionals worldwide. Management of these conditions requires a holistic approach to improve patients' overall health, treatment outcomes, and quality of life, preventing diabetes complications and cancer treatment side-effects. In this article, a multidisciplinary panel of experts from different Italian scientific societies provide a critical overview of the co-management of cancer and diabetes, with an increasing focus on identifying a novel specialty field, 'diabeto-oncology', and suggest new co-management models of cancer patients with diabetes to improve their care. To better support cancer patients with diabetes and ensure high levels of coordinated care between oncologists and diabetologists, 'diabeto-oncology' could represent a new specialized field that combines specific expertise, skills, and training.


Diabetes Mellitus , Neoplasms , Humans , Quality of Life , Consensus , Neoplasms/complications , Neoplasms/epidemiology , Neoplasms/therapy , Medical Oncology , Diabetes Mellitus/epidemiology , Diabetes Mellitus/therapy , Italy/epidemiology
2.
J Endocrinol Invest ; 46(11): 2213-2236, 2023 Nov.
Article En | MEDLINE | ID: mdl-37378828

BACKGROUND: Adaptive thermogenesis represents the main mechanism through which the body generates heat in response to external stimuli, a phenomenon that includes shivering and non-shivering thermogenesis. The non-shivering thermogenesis is mainly exploited by adipose tissue characterized by a brown aspect, which specializes in energy dissipation. A decreased amount of brown adipose tissue has been observed in ageing and chronic illnesses such as obesity, a worldwide health problem characterized by dysfunctional adipose tissue expansion and associated cardiometabolic complications. In the last decades, the discovery of a trans-differentiation mechanism ("browning") within white adipose tissue depots, leading to the generation of brown-like cells, allowed to explore new natural and synthetic compounds able to favour this process and thus enhance thermogenesis with the aim of counteracting obesity. Based on recent findings, brown adipose tissue-activating agents could represent another option in addition to appetite inhibitors and inhibitors of nutrient absorption for obesity treatment. PURPOSE: This review investigates the main molecules involved in the physiological (e.g. incretin hormones) and pharmacological (e.g. ß3-adrenergic receptors agonists, thyroid receptor agonists, farnesoid X receptor agonists, glucagon-like peptide-1, and glucagon receptor agonists) modulation of adaptive thermogenesis and the signalling mechanisms involved.

3.
ESMO Open ; 8(3): 101573, 2023 Jun.
Article En | MEDLINE | ID: mdl-37263082

Increasing evidence suggests that patients with diabetes, particularly type 2 diabetes (T2D), are characterized by an increased risk of developing different types of cancer, so cancer could be proposed as a new T2D-related complication. On the other hand, cancer may also increase the risk of developing new-onset diabetes, mainly caused by anticancer therapies. Hyperinsulinemia, hyperglycemia, and chronic inflammation typical of T2D could represent possible mechanisms involved in cancer development in diabetic patients. MicroRNAs (miRNAs) are a subset of non-coding RNAs, ⁓22 nucleotides in length, which control the post-transcriptional regulation of gene expression through both translational repression and messenger RNA degradation. Of note, miRNAs have multiple target genes and alteration of their expression has been reported in multiple diseases, including T2D and cancer. Accordingly, specific miRNA-regulated pathways are involved in the pathogenesis of both conditions. In this review, a panel of experts from the Italian Association of Medical Oncology (AIOM), Italian Association of Medical Diabetologists (AMD), Italian Society of Diabetology (SID), Italian Society of Endocrinology (SIE), and Italian Society of Pharmacology (SIF) provide a critical view of the evidence about the involvement of miRNAs in the pathophysiology of both T2D and cancer, trying to identify the shared miRNA signature and pathways able to explain the strong correlation between the two conditions, as well as to envision new common pharmacological approaches.


Diabetes Mellitus, Type 2 , MicroRNAs , Neoplasms , Humans , Diabetes Mellitus, Type 2/complications , Diabetes Mellitus, Type 2/genetics , Diabetes Mellitus, Type 2/physiopathology , Diabetes Mellitus, Type 2/therapy , Neoplasms/complications , Neoplasms/genetics , Neoplasms/therapy , MicroRNAs/genetics , MicroRNAs/metabolism , Insulin-Secreting Cells/pathology , Insulin Resistance/genetics , Molecular Targeted Therapy/trends
5.
J Endocrinol Invest ; 45(9): 1663-1671, 2022 Sep.
Article En | MEDLINE | ID: mdl-35476320

PURPOSE: To evaluate if a web-based telemedicine system (the Glucoonline® system) is effective to improve glucose control in insulin-treated patients with type 1 and type 2 diabetes, as compared to standard of care. METHODS: This was a prospective, randomized, controlled trial, carried out at three tertiary referral centers for diabetes in Italy. Adults with insulin-treated type 1 and type 2 diabetes, inadequate glycemic control, and no severe diabetes-related complications and/or comorbidities were eligible for this study. Patients were randomized to either perform telemedicine-assisted (Group A) or standard (Group B) self-monitoring blood glucose (SMBG) for 6 months. In Group A, patients received prompt feedback about their blood glucose levels and therapy suggestions from the study staff via phone/SMS, when appropriate. In Group B, patients had no remote assistance from the study staff between planned visits. RESULTS: 123 patients were included in the final analysis. After 6 months, patients achieved a significant reduction in HbA1c in Group A (-0.38%, p < 0.05) but not in Group B (+ 0.08%, p = 0.53). A significant difference in the percentage of patients with HbA1c < 7% between Group A and Group B was found after 3 months (28.6% vs 11.1%, p = 0.02). Also, fewer patients (p < 0.05) with HbA1c > 8.5% were found in Group A vs Group B, respectively, after both 3 months (14.3% vs 35.2%) and 6 months (21.8% vs 42.9%). CONCLUSIONS: The use of the Glucoonline™ system resulted in improved metabolic control. Telemedicine services have potential to support diabetes self-management and provide the patients with remote, prompt assistance using affordable technological equipment. Trial registration This study was registered at clinicaltrials.gov (NCT01804803) on March 5, 2013.


Diabetes Mellitus, Type 1 , Diabetes Mellitus, Type 2 , Telemedicine , Adult , Blood Glucose/analysis , Blood Glucose Self-Monitoring/methods , Diamond , Glycated Hemoglobin/analysis , Humans , Hypoglycemic Agents/therapeutic use , Insulin/therapeutic use , Prospective Studies , Telemedicine/methods
6.
J Endocrinol Invest ; 44(12): 2741-2748, 2021 Dec.
Article En | MEDLINE | ID: mdl-34173961

INTRODUCTION: Obstructive sleep apnoea (OSA) is an underdiagnosed condition frequently associated with glycaemic control impairment in patients with type 2 diabetes. AIM: To assess the relationship between glycometabolic parameters and OSA in obese non-diabetic subjects. METHODS: Ninety consecutive subjects (mean age 44.9 ± 12 years, mean BMI 42.1 ± 9 kg/m2) underwent polysomnography and a 2-h oral glucose tolerance test (OGTT). RESULTS: OSA was identified in 75% of subjects, with a higher prevalence of males compared to the group of subjects without OSA (62% vs 32%, p = 0.02). Patients with OSA had comparable BMI (42.8 kg/m2 vs 39.4 kg/m2), a higher average HbA1c (5.8% vs 5.4%, p < 0.001), plasma glucose at 120 min during OGTT (2 h-PG; 123 mg/dl vs 97 mg/dl, p = 0.009) and diastolic blood pressure (81.1 mmHg vs 76.2 mmHg, p = 0.046) than obese subjects without OSA. HbA1c and 2 h-PG were found to be correlated with the apnoea-hypopnoea index (AHI; r = 0.35 and r = 0.42, respectively) and with percent of sleep time with oxyhaemoglobin saturation < 90% (ST90; r = 0.44 and r = 0.39, respectively). Further, in a linear regression model, ST90 and AHI were found to be the main determinants of 2 h-PG (ß = 0.81, p < 0.01 and ß = 0.75, p = 0.02, respectively) after controlling for age, sex, waist circumference, physical activity, and C-reactive protein. Similarly, ST90 and AHI persisted as independent determinants of HbA1c (ß = 0.01, p = 0.01 and ß = 0.01, p = 0.01, respectively). CONCLUSION: Beyond the traditional clinical parameters, the presence of a normal-high value of 2 h-PG and HbA1c should raise suspicion of the presence of OSA in obese subjects.


Blood Glucose/metabolism , Glycated Hemoglobin/analysis , Hyperglycemia , Obesity , Sleep Apnea, Obstructive , Adult , Body Mass Index , Female , Glucose Tolerance Test/methods , Humans , Hyperglycemia/diagnosis , Hyperglycemia/epidemiology , Hyperglycemia/etiology , Male , Obesity/diagnosis , Obesity/epidemiology , Obesity/metabolism , Obesity/physiopathology , Polysomnography/methods , Postprandial Period , Prevalence , Risk Factors , Severity of Illness Index , Sleep Apnea, Obstructive/blood , Sleep Apnea, Obstructive/diagnosis , Sleep Apnea, Obstructive/epidemiology , Sleep Apnea, Obstructive/physiopathology
7.
ESMO Open ; 6(3): 100153, 2021 06.
Article En | MEDLINE | ID: mdl-33984679

Most anticancer molecules are administered in body-size-based dosing schedules, bringing up unsolved issues regarding pharmacokinetic data in heavy patients. The worldwide spread of obesity has not been matched by improved methods and strategies for tailored drug dosage in this population. The weight or body surface area (BSA)-based approaches may fail to fully reflect the complexity of the anthropometric features besides obesity in cancer patients suffering from sarcopenia. Likewise, there is a lack of pharmacokinetic data on obese patients for the majority of chemotherapeutic agents as well as for new target drugs and immunotherapy. Therefore, although the available findings point to the role of dose intensity in cancer treatment, and support full weight-based dosing, empirical dose capping often occurs in clinical practice in order to avoid toxicity. Thus a panel of experts of the Associazione Italiana Oncologia Medica (AIOM), Associazione Medici Diabetologi (AMD), Società Italiana Endocrinologia (SIE), and Società Italiana Farmacologia (SIF), provides here a consensus statement for appropriate cytotoxic chemotherapy and new biological cancer drug dosing in obese patients.


Antineoplastic Agents , Neoplasms , Physicians , Consensus , Humans , Neoplasms/complications , Neoplasms/drug therapy , Obesity/complications
8.
ESMO Open ; 6(3): 100155, 2021 06.
Article En | MEDLINE | ID: mdl-34020401

Pancreatic cancer (PC) is a common cause of cancer-related death, due to difficulties in detecting early-stage disease, to its aggressive behaviour, and to poor response to systemic therapy. Therefore, developing strategies for early diagnosis of resectable PC is critical for improving survival. Diabetes mellitus is another major public health problem worldwide. Furthermore, diabetes can represent both a risk factor and a consequence of PC: nowadays, the relationship between these two diseases is considered a high priority for research. New-onset diabetes can be an early manifestation of PC, especially in a thin adult without a family history of diabetes. However, even if targeted screening for patients at higher risk of PC could be a promising approach, this is not recommended in asymptomatic adults with new-onset diabetes, due to the much higher incidence of hyperglycaemia than PC and to the lack of a safe and affordable PC screening test. Prompted by a well-established and productive multidisciplinary cooperation, the Italian Association of Medical Oncology (AIOM), the Italian Medical Diabetologists Association (AMD), the Italian Society of Endocrinology (SIE), and the Italian Society of Pharmacology (SIF) here review available evidence on the mechanisms linking diabetes and PC, addressing the feasibility of screening for early PC in patients with diabetes, and sharing a set of update statements with the aim of providing a state-of-the-art overview and a decision aid tool for daily clinical practice.


Diabetes Mellitus , Pancreatic Neoplasms , Physicians , Consensus , Diabetes Mellitus/diagnosis , Diabetes Mellitus/epidemiology , Humans , Medical Oncology , Pancreatic Neoplasms/diagnosis , Pancreatic Neoplasms/epidemiology
9.
J Endocrinol Invest ; 44(5): 921-941, 2021 May.
Article En | MEDLINE | ID: mdl-33145726

The way by which subcutaneous adipose tissue (SAT) expands and undergoes remodeling by storing excess lipids through expansion of adipocytes (hypertrophy) or recruitment of new precursor cells (hyperplasia) impacts the risk of developing cardiometabolic and respiratory diseases. In unhealthy obese subjects, insulin resistance, type 2 diabetes, hypertension, and obstructive sleep apnoea are typically associated with pathologic SAT remodeling characterized by adipocyte hypertrophy, as well as chronic inflammation, hypoxia, increased visceral adipose tissue (VAT), and fatty liver. In contrast, metabolically healthy obese individuals are generally associated with SAT development characterized by the presence of smaller and numerous mature adipocytes, and a lower degree of VAT inflammation and ectopic fat accumulation. The remodeling of SAT and VAT is under genetic regulation and influenced by inherent depot-specific differences of adipose tissue-derived stem cells (ASCs). ASCs have multiple functions such as cell renewal, adipogenic capacity, and angiogenic properties, and secrete a variety of bioactive molecules involved in vascular and extracellular matrix remodeling. Understanding the mechanisms regulating the proliferative and adipogenic capacity of ASCs from SAT and VAT in response to excess calorie intake has become a focus of interest over recent decades. Here, we summarize current knowledge about the biological mechanisms able to foster or impair the recruitment and adipogenic differentiation of ASCs during SAT and VAT development, which regulate body fat distribution and favorable or unfavorable metabolic responses.


Adipogenesis/physiology , Adipose Tissue , Lipogenesis/genetics , Obesity , Adipocytes/metabolism , Adipose Tissue/metabolism , Adipose Tissue/pathology , Body Fat Distribution , Gene Expression Regulation , Humans , Insulin Resistance , Mesenchymal Stem Cells/metabolism , Obesity/immunology , Obesity/metabolism , Obesity/pathology
10.
Nutr Metab Cardiovasc Dis ; 26(4): 333-44, 2016 Apr.
Article En | MEDLINE | ID: mdl-26947594

BACKGROUND AND AIMS: Since treatment with insulin detemir results in a lower weight gain compared to human insulin, we investigated whether detemir is associated with lower ability to promote adipogenesis and/or lipogenesis in human adipose stem cells (ASC). METHODS AND RESULTS: Human ASC isolated from both the subcutaneous and visceral adipose tissues were differentiated for 30 days in the presence of human insulin or insulin detemir. Nile Red and Oil-Red-O staining were used to quantify the rate of ASC conversion to adipocytes and lipid accumulation, respectively. mRNA expression levels of early genes, including Fos and Cebpb, as well as of lipogenic and adipogenic genes, were measured at various phases of differentiation by qRT-PCR. Activation of insulin signaling was assessed by immunoblotting. ASC isolated from subcutaneous and visceral adipose tissue were less differentiated when exposed to insulin detemir compared to human insulin, showing lower rates of adipocyte conversion, reduced triglyceride accumulation, and impaired expression of late-phase adipocyte marker genes, such as Pparg2, Slc2a4, Adipoq, and Cidec. However, no differences in activation of insulin receptor, Akt and Erk and induction of the early genes Fos and Cebpb were observed between insulin detemir and human insulin. CONCLUSION: Insulin detemir displays reduced induction of the Pparg2 adipocyte master gene and diminished effects on adipocyte differentiation and lipogenesis in human subcutaneous and visceral ASC, in spite of normal activation of proximal insulin signaling reactions. These characteristics of insulin detemir may be of potential relevance to its weight-sparing effects observed in the clinical setting.


Adipocytes/drug effects , Hypoglycemic Agents/pharmacology , Insulin Detemir/pharmacology , Insulin, Long-Acting/pharmacology , Stem Cells/drug effects , Adipocytes/cytology , Adipogenesis/drug effects , Adiponectin/genetics , Adiponectin/metabolism , Adult , Aged , Aged, 80 and over , Apoptosis Regulatory Proteins , CCAAT-Enhancer-Binding Protein-beta/genetics , CCAAT-Enhancer-Binding Protein-beta/metabolism , Cell Differentiation/drug effects , Female , Glucose Transporter Type 4/genetics , Glucose Transporter Type 4/metabolism , Humans , Insulin/metabolism , Intra-Abdominal Fat/cytology , Lipogenesis/drug effects , Male , Middle Aged , PPAR gamma/genetics , PPAR gamma/metabolism , Proteins/genetics , Proteins/metabolism , Proto-Oncogene Proteins c-akt/genetics , Proto-Oncogene Proteins c-akt/metabolism , RNA, Messenger/genetics , RNA, Messenger/metabolism , Signal Transduction , Stem Cells/metabolism , Subcutaneous Fat/cytology
11.
Endocrinology ; 153(12): 5770-81, 2012 Dec.
Article En | MEDLINE | ID: mdl-23077074

Increased apoptosis of cardiac progenitor cells (CPCs) has been proposed as a mechanism of myocardial damage and dysfunction. Glucagon-like peptide-1 (GLP-1) has been shown to improve heart recovery and function after ischemia and to promote cell survival. The protective effects of GLP-1 on oxidative stress-induced apoptosis were investigated in human CPCs isolated from human heart biopsies. Mesenchymal-type cells were isolated from human heart biopsies, exhibited the marker profile of CPCs, differentiated toward the myocardiocyte, adipocyte, chondrocyte, and osteocyte lineages under appropriate culture conditions, and expressed functional GLP-1 receptors. CPCs were incubated with GLP-1 with or without hydrogen peroxide (H(2)O(2)). Phospho- and total proteins were detected by immunoblotting and immunofluorescence analysis. Gene expression was evaluated by quantitative RT-PCR. The role of the canonical GLP-1 receptor was assessed by using the receptor antagonist exendin(9-39) and receptor-specific silencer small interfering RNAs. Cell apoptosis was quantified by an ELISA assay and by flow cytometry-detected Annexin V. Exposure of CPCs to H(2)O(2) induced a 2-fold increase in cell apoptosis, mediated by activation of the c-Jun N-terminal protein kinase (JNK) pathway. Preincubation of CPCs with GLP-1 avoided H(2)O(2)-triggered JNK phosphorylation and nuclear localization, and protected CPCs from apoptosis. The GLP-1 effects were markedly reduced by coincubation with the receptor antagonist exendin(9-39), small interfering RNA-mediated silencing of the GLP-1 receptor, and pretreatment with the protein kinase A inhibitor H89. In conclusion, activation of GLP-1 receptors prevents oxidative stress-mediated apoptosis in human CPCs by interfering with JNK activation and may represent an important mechanism for the cardioprotective effects of GLP-1.


Apoptosis , Glucagon-Like Peptide 1/metabolism , JNK Mitogen-Activated Protein Kinases/metabolism , Myocardium/cytology , Oxidative Stress , Stem Cells/cytology , Annexin A5/pharmacology , Biopsy , Cell Differentiation , Cell Nucleus/metabolism , Cells, Cultured , Enzyme Activation , Enzyme-Linked Immunosorbent Assay/methods , Flow Cytometry/methods , Humans , Hydrogen Peroxide/metabolism , JNK Mitogen-Activated Protein Kinases/antagonists & inhibitors , Models, Biological , Peptide Fragments/pharmacology , Phosphorylation , RNA, Small Interfering/metabolism , Signal Transduction
12.
J Endocrinol Invest ; 34(1): 69-77, 2011 Jan.
Article En | MEDLINE | ID: mdl-21233599

Type 2 diabetes mellitus is increasing in prevalence at alarming rates. Concurrent with its expanding prevalence is the increase in the related risk of morbidity and mortality. Because diabetic patients are prone to cardiovascular disease, treatment strategies should address the cardiovascular risk factors, including blood pressure, lipids, and body weight, in addition to the glycemic aspects of the disease. Newer agents, such as glucagon-like peptide-1 (GLP-1) analogs and dipeptidyl peptidase-4 (DPP-4) inhibitors, have varying degrees of evidence to support their effects on body weight, blood pressure, and lipid levels, beyond glycated hemoglobin reduction. While GLP-1 agonists produce a weight loss, the DPP-4 inhibitors, conversely, appear to have a weight-neutral effect. Substantial evidence demonstrates that both medications produce modest reductions in systolic blood pressure and, in some cases, diastolic blood pressure, and reduce several markers of cardiovascular risk, including C-reactive protein. Moreover, GLP-1 influences endothelial function. The effect of the incretin hormones on serum lipids are either neutral or beneficial, with small, non-significant decreases in LDL cholesterol, increases in HDL cholesterol, and occasionally significant decreases in fasting triglyceride levels. Also, they have positive effects on hepatic steatosis. Although GLP-1 agonists and DPP-4 inhibitors are at present not appropriate for primary treatment of cardiovascular risks factors, the reduction of these parameters is evidently beneficial.


Combined Modality Therapy/methods , Diabetes Mellitus, Type 2/therapy , Incretins/therapeutic use , Animals , Combined Modality Therapy/trends , Diabetes Mellitus, Type 2/blood , Diabetes Mellitus, Type 2/complications , Glucagon-Like Peptide 1/pharmacology , Health Services Needs and Demand , Humans , Incretins/physiology , Models, Biological , Patient Care Planning/trends
13.
J Endocrinol Invest ; 34(8): 599-603, 2011 Sep.
Article En | MEDLINE | ID: mdl-20820129

BACKGROUND: With the increasing use of thyroid ultrasound, the recognition of thyroid nodules in a large proportion of apparently healthy subjects has become common. Because also the papillary thyroid microcarcinomas (PTMC) are being increasingly discovered, it is important to ascertain whether PTMC may exhibit heterogenous clinical features, associated with different aggressiveness. AIM: We retrospectively examined 122 subjects [98 female (80.3%), and 24 male (19.7%)] with thyroid cancer to find potential clinical and pathological findings that could be predictive of clinically aggressive behavior. RESULTS: Twenty of the 31 patients with true incidental cancer (64.5%) in comparison to 20 of the 91 patients with non-incidental cancer (21.9%) had a diameter <10 mm, and this difference was statistically significant (p<0.0001). There was a statistically significant association between size and invasiveness because 19.3% of invasive cancers were <10 mm whereas 44.6% of non-invasive cancers were <10 mm (p=0.005). The relationship between incidental discovery and invasiveness was also evaluated, but the proportion of incidental invasive cancer (19.3%) was not significantly different from that of incidental non-invasive cancer (30.8%). In the multivariate analysis, only size <10 mm (odds ratio=0.35, p=0.013) and papillary vs other histotypes (odds ratio=0.35, p=0.04) were statistically significant protective factors against invasiveness. CONCLUSIONS: a) Incidentally discovered thyroid cancers are more frequently microcarcinomas; b) there appears to be no difference in terms of invasive behavior between incidental and non-incidental thyroid cancer; c) smaller tumor size emerges as a protective factor.


Neoplasm Invasiveness/pathology , Thyroid Neoplasms/pathology , Adult , Aged , Female , Humans , Male , Middle Aged , Neoplasm Metastasis , Odds Ratio , Retrospective Studies , Risk Factors , Thyroid Neoplasms/diagnostic imaging , Thyroid Neoplasms/physiopathology , Ultrasonography
14.
Diabetologia ; 51(1): 155-64, 2008 Jan.
Article En | MEDLINE | ID: mdl-17960360

AIM/HYPOTHESIS: The distinct metabolic properties of visceral and subcutaneous adipocytes may be due to inherent characteristics of the cells that are resident in each fat depot. To test this hypothesis, human adipocytes were differentiated in vitro from precursor stromal cells obtained from visceral and subcutaneous fat depots and analysed for genetic, biochemical and metabolic endpoints. METHODS: Stromal cells were isolated from adipose tissue depots of nondiabetic individuals. mRNA levels of adipocyte-specific proteins were determined by real-time RT-PCR. Insulin signalling was evaluated by immunoblotting with specific antibodies. Glucose transport was measured by a 2-deoxy-glucose uptake assay. Adiponectin secretion in the adipocyte-conditioned medium was determined by a specific RIA. RESULTS: With cell differentiation, mRNA levels of PPARG, C/EBPalpha (also known as CEBPA), AP2 (also known as GTF3A), GLUT4 (also known as SLC2A4) were markedly upregulated, whereas GLUT1 (also known as SLC2A1) mRNA did not change. However, expression of C/EBPalpha, AP2 and adiponectin was higher in subcutaneous than in visceral adipocytes. By contrast, adiponectin was secreted at threefold higher rates by visceral than by subcutaneous adipocytes while visceral adipocytes also showed two- to threefold higher insulin-stimulated glucose uptake. Insulin-induced phosphorylation of the insulin receptor, IRS proteins, Akt and extracellular signal-regulated kinase-1/2 was more rapid and tended to decrease at earlier time-points in visceral than in subcutaneous adipocytes. CONCLUSIONS/INTERPRETATION: Subcutaneous and visceral adipocytes, also when differentiated in vitro from precursor stromal cells, retain differences in gene expression, adiponectin secretion, and insulin action and signalling. Thus, the precursor cells that reside in the visceral and subcutaneous fat depots may already possess inherent and specific metabolic characteristics that will be expressed upon completion of the differentiation programme.


Adipocytes/metabolism , Adiponectin/metabolism , Gene Expression Profiling , Gene Expression Regulation , Insulin/metabolism , Stromal Cells/cytology , Adipose Tissue/metabolism , Adult , Female , Glucose/metabolism , Humans , In Vitro Techniques , Male , Middle Aged , Radioimmunoassay , Signal Transduction , Stromal Cells/metabolism
15.
J Endocrinol Invest ; 28(3 Suppl): 85-93, 2005.
Article En | MEDLINE | ID: mdl-16042365

DHEA and its sulfate prohormone DHEAS are the most abundant circulating adrenal steroid hormones in humans. DHEA exerts its actions on peripheral target tissues either indirectly, following its conversion to androgens, estrogens or both, or directly, as a steroid hormone interacting with either a nuclear or a membrane receptor. In humans, DHEA shows a characteristic pattern of secretion throughout life. Serum DHEA concentrations decline with advancing age and vary with gender, ethnicity, and environmental factors. Epidemiological studies show an inverse relationship between plasma DHEA(S) levels in men and age-related illnesses, including cardiovascular and metabolic diseases, immune disorders, malignancies, and neurological dysfunction. This has generated great interest on the putative role of DHEA in age-associated illnesses. Administration of DHEA to rats and mice reduces visceral fat accumulation, and improves insulin resistance in experimental models of diet-induced obesity and/or Type 2 diabetes. In addition, recent studies in vitro have shown that DHEA has the capacity to improve endothelial function by increasing nitric oxide (NO) synthesis. Replacement of DHEA in patients with adrenal insufficiency has been shown to exert beneficial effects on well-being, mood, and sexuality. By contrast, in healthy individuals, the physiological age-associated decline in circulating DHEA(S) per se does not justify DHEA supplementation, since the effects of this hormone on metabolic abnormalities, endothelial function in vivo, and cardiovascular events are contradictory. However, these results do not exclude the possibility that DHEA treatment may prove beneficial in specific subgroups of elderly subjects.


Aging , Dehydroepiandrosterone Sulfate/blood , Adrenal Insufficiency , Affect , Animals , Body Composition/drug effects , Bone Density , Dehydroepiandrosterone Sulfate/administration & dosage , Dehydroepiandrosterone Sulfate/metabolism , Diabetes Mellitus, Type 2 , Endothelium, Vascular/drug effects , Hormone Replacement Therapy , Humans , Insulin Resistance , Male , Neoplasms , Obesity
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