Advanced Glycation End Products: New Clinical and Molecular Perspectives.

Diabetes mellitus (DM) is considered one of the most massive epidemics of the twenty-first century due to its high mortality rates caused mainly due to its complications; therefore, the early identification of such complications becomes a race against time to establish a prompt diagnosis. The research of complications of DM over the years has allowed the development of numerous alternatives for diagnosis. Among these emerge the quantification of advanced glycation end products (AGEs) given their increased levels due to chronic hyperglycemia, while also being related to the induction of different stress-associated cellular responses and proinflammatory mechanisms involved in the progression of chronic complications of DM. Additionally, the investigation for more valuable and safe techniques has led to developing a newer, noninvasive, and effective tool, termed skin fluorescence (SAF). Hence, this study aimed to establish an update about the molecular mechanisms induced by AGEs during the evolution of chronic complications of DM and describe the newer measurement techniques available, highlighting SAF as a possible tool to measure the risk of developing DM chronic complications.

Metabolic Syndrome and Subclinical Hypothyroidism: A Type 2 Diabetes-Dependent Association.

INTRODUCTION: Subclinical hypothyroidism (ScH) is an endocrine alteration that is related to cardiovascular risk factors, including those categorized as components of the Metabolic Syndrome (MS). However, findings in prior reports regarding an association between these alterations are inconsistent. The purpose of this study was to determine the relationship between both entities in adult subjects from Maracaibo City, Venezuela. MATERIALS AND METHODS: The Maracaibo City Metabolic Syndrome Prevalence Study is a descriptive, cross-sectional study with random and multistage sampling. In this substudy, 391 individuals of both genders were selected and TSH, free T3, and free T4 tests were performed as well as a complete lipid profile, fasting glycaemia, and insulin blood values. ScH was defined according to the National Health and Nutrition Examination Survey (NHANES) criteria: high TSH (≥4.12mUI/L) and normal free T4 (0.9-1,9 ng/dL) in subjects without personal history of thyroid disease. MS components were defined according to IDF/AHA/NHLBI/WHF/IAS/IASO-2009 criteria. A multiple logistic regression analysis was used to assess the relationship between MS components and ScH diagnosis. RESULTS: Of the evaluated population, 10.5% (n=41) was diagnosed with ScH, with a higher prevalence in women (female: 13.6% versus male: 7.7%; χ2=3.56, p=0.05). Likewise, 56.1% (n=23) of the subjects with ScH were diagnosed with MS (χ2=4.85; p=0.03), being hyperglycemia the main associated criterion (χ2=11.7; p=0.001). In multivariable analysis, it was observed that the relationship was exclusive with the presence of type 2 diabetes mellitus (T2DM) OR: 3.22 (1.14-9.14); p=0.03. CONCLUSION: The relationship between ScH and MS in our population is dependent on the presence of hyperglycemia, specifically T2DM diagnosis, findings that vary from those previously reported in Latin American subjects.

Prevalence and Associated Factors of Insulin Resistance in Adults from Maracaibo City, Venezuela.

Background and Aim. Insulin resistance (IR) is a prominent pathophysiologic component in a myriad of metabolic disorders, including obesity, prediabetes, and type 2 diabetes mellitus, which are common in our locality. The objective of this study was to determine the prevalence of IR and factors associated with this condition in an adult population from Maracaibo city, Venezuela. Methodology. A cross-sectional, descriptive study with multistaged randomized sampling was carried out in 2026 adults. IR was defined as HOMA2-IR ≥ 2. A multiple logistic regression model was constructed in order to evaluate factors associated with IR. Results. The prevalence of IR was 46.5% (n = 943), with 46.7% (n = 450) in the general population, 46.4% (n = 493) in females, and 47.90% (n = 970) in males (p = 0.895). IR prevalence tended to increase with age and was significantly greater in subjects aged ≥30 years (χ (2) = 16.726; p = 2.33 × 10(-4)). Employment, alcohol consumption, obesity, high triacylglycerides, low HDL-C, and dysglycemia were associated with greater odds of IR, whereas a high level of physical activity appeared to be weak protective factor against IR. Conclusions. The prevalence of IR is elevated in our locality. The main determinants of this condition appear to be the presence of obesity, high triacylglycerides, low HDL-C, dysglycemia, and alcohol intake.

Diabetes and Impaired Fasting Glucose Prediction Using Anthropometric Indices in Adults from Maracaibo City, Venezuela.

To determine the predictive power of various anthropometric indices for the identification of dysglycemic states in Maracaibo, Venezuela. A cross-sectional study with randomized, multi-staged sampling was realized in 2230 adult subjects of both genders who had their body mass index (BMI), waist circumference (WC) and waist-height ratio (WHR) determined. Diagnoses of type 2 diabetes mellitus (DM2) and impaired fasting glucose (IFG) were made following ADA 2015 criteria. ROC curves were used to evaluate the predictive power of each anthropometric parameter. Area under the curve (AUC) values were compared through Delong's test. Of the total 2230 individuals (52.6 % females), 8.4 % were found to have DM2, and 19.5 % had IFG. Anthropometric parameters displayed greater predictive power regarding newly diagnosed diabetics, where WHR was the most important predictor in both females (AUC = 0.808; CI 95 % 0.715-0.900. Sensitivity: 82.8 %; specificity: 76.2 %) and males (AUC = 0.809; CI 95 % 0.736-0.882. Sensitivity: 78.6 %; specificity: 68.1 %), although all three parameters appeared to have comparable predictive power in this subset. In previously diagnosed diabetic subjects, WHR was superior to both WC and BMI in females, and WHR and WC were both superior to BMI in males. Lower predictive values were found for IFG in both genders. Accumulation of various altered anthropometric measurements was associated with increased odds ratios for both newly and previously diagnosed DM2. The predictive power of anthropometric measurements was greater for DM2 than IFG. We suggest assessment of as many available parameters as possible in the clinical setting.

Sensitivity and Specificity Improvement in Abdominal Obesity Diagnosis Using Cluster Analysis during Waist Circumference Cut-Off Point Selection.

INTRODUCTION: The purpose of this study was to analyze the influence of metabolic phenotypes during the construction of ROC curves for waist circumference (WC) cutpoint selection. MATERIALS AND METHODS: A total of 1,902 subjects of both genders were selected from the Maracaibo City Metabolic Syndrome Prevalence Study database. Two-Step Cluster Analysis (TSCA) was applied to select metabolically healthy and sick men and women. ROC curves were constructed to determine WC cutoff points by gender. RESULTS: Through TSCA, metabolic phenotype predictive variables were selected: HOMA2-IR and HOMA2-ßcell for women and HOMA2-IR, HOMA2-ßcell, and TAG for men. Subjects were classified as healthy normal weight, metabolically obese normal weight, healthy and metabolically disturbed overweight, and healthy and metabolically disturbed obese. Final WC cutpoints were 91.50 cm for women (93.4% sensitivity, 93.7% specificity) and 98.15 cm for men (96% sensitivity, 99.5% specificity). CONCLUSIONS: TSCA in the selection of the groups used in ROC curves construction proved to be an important tool, aiding in the detection of MOWN and MHO which cannot be identified with WC alone. The resulting WC cutpoints were <91.00 cm for women and <98.00 cm for men. Furthermore, anthropometry is insufficient to determine healthiness, and, biochemical analysis is needed to properly filter subjects during classification.

Glucococorticoid-induced death of pancreatic Beta cells: an organized chaos.

Glucocorticoids (GC) are renowned for their pleiotropic effects in all organ systems, their ubiquitous use in numerous clinical settings, and the abundant adverse effects they may exert, particularly in the endocrine-metabolic sphere. Although hyperglycemia and insulin resistance are well-defined GC-induced diabetogenic phenomena, an added component of direct injury to pancreatic ß cells (PBC) may also participate in this scenario. Indeed, the apoptotic capacity of GC is widely recognized, and PBC do not escape this situation. No unified pathway has been characterized regarding GC-induced cell death; instead, it appears to depend on the specific machinery of each cell type, determining a great heterogeneity in GC-dependent apoptotic mechanisms among different tissues. In PBC, GC can induce the expression or activation of pro-apoptotic proteins (Bax, BAD, p38), repress anti-apoptotic proteins (Bcl-2), deactivate pro-survival mechanisms (cAMP-PKA signaling) and sensitize the cell to death induced by oxidative stress, fatty acids, hyperglycemia and cytokines. Although proliferative pathways (TGF-ß, H-ras) are activated simultaneously - and an increase in PBC mass may be observed initially - pro-apoptotic and anti-proliferative mechanisms appear to eventually overcome their pro-survival counterparts, due to their synergic and aggregative action. Key molecules such as p38 and the cAMP-PKA system may be promising therapeutic targets in the prevention of GC-induced cell death.

Relationship between Alcohol Consumption and Components of the Metabolic Syndrome in Adult Population from Maracaibo City, Venezuela.

Introduction. Although the relationships between alcohol and disorders such as cancer and liver disease have been thoroughly researched, its effects on cardiometabolic health remain controversial. Therefore, the objective of this study was to assess the association between alcohol consumption, the Metabolic Syndrome (MS), and its components in our locality. Materials and Methods. Descriptive, cross-sectional study with randomized, multistaged sampling, which included 2,230 subjects of both genders. Two previously determined population-specific alcohol consumption pattern classifications were utilized in each gender: daily intake quartiles and conglomerates yielded by cluster analysis. MS was defined according to the 2009 consensus criteria. Association was evaluated through various multiple logistic regression models. Results. In univariate analysis (daily intake quartiles), only hypertriacylglyceridemia was associated with alcohol consumption in both genders. In multivariate analysis, daily alcohol intake ≤3.8 g/day was associated with lower risk of hypertriacylglyceridemia in females (OR = 0.29, CI 95%: 0.09-0.86; p = 0.03). Among men, subjects consuming 28.41-47.33 g/day had significantly increased risk of MS, hyperglycemia, high blood pressure, hypertriacylglyceridemia, and elevated waist circumference. Conclusions. The relationship between drinking, MS, and its components is complex and not directly proportional. Categorization by daily alcohol intake quartiles appears to be the most efficient method for quantitative assessment of alcohol consumption in our region.

Epidemiologic Behavior and Estimation of an Optimal Cut-Off Point for Homeostasis Model Assessment-2 Insulin Resistance: A Report from a Venezuelan Population.

Background. Mathematical models such as Homeostasis Model Assessment have gained popularity in the evaluation of insulin resistance (IR). The purpose of this study was to estimate the optimal cut-off point for Homeostasis Model Assessment-2 Insulin Resistance (HOMA2-IR) in an adult population of Maracaibo, Venezuela. Methods. Descriptive, cross-sectional study with randomized, multistaged sampling included 2,026 adult individuals. IR was evaluated through HOMA2-IR calculation in 602 metabolically healthy individuals. For cut-off point estimation, two approaches were applied: HOMA2-IR percentile distribution and construction of ROC curves using sensitivity and specificity for selection. Results. HOMA2-IR arithmetic mean for the general population was 2.21 ± 1.42, with 2.18 ± 1.37 for women and 2.23 ± 1.47 for men (P = 0.466). When calculating HOMA2-IR for the healthy reference population, the resulting p75 was 2.00. Using ROC curves, the selected cut-off point was 1.95, with an area under the curve of 0.801, sensibility of 75.3%, and specificity of 72.8%. Conclusions. We propose an optimal cut-off point of 2.00 for HOMA2-IR, offering high sensitivity and specificity, sufficient for proper assessment of IR in the adult population of our city, Maracaibo. The determination of population-specific cut-off points is needed to evaluate risk for public health problems, such as obesity and metabolic syndrome.

Variations of lipoprotein(a) levels in the metabolic syndrome: a report from the Maracaibo City Metabolic Syndrome Prevalence Study.

BACKGROUND: Lipoprotein(a) [Lp(a)] is a known risk factor for cardiovascular disease, yet its influence on metabolic syndrome (MS) is still controversial. The purpose of this study was to assess the impact generated by this diagnosis in serum Lp(a) concentrations. MATERIALS AND METHODS: A total of 1807 subjects of both genders (55.3% women and 44.7% men) belonging to the Maracaibo City Metabolic Syndrome Prevalence Study were evaluated. Results were expressed as Mean ± SD, determining differences through Student's t-test and One-Way ANOVA test. Multiple logistic regression models were utilized for analyzing factors associated with elevated serum Lp(a) levels and MS. Total cholesterol and LDL-C were corrected according to Lp(a)-Cholesterol when necessary. RESULTS: No differences were found in Lp(a) values between genders; P = 0,292. The association between MS and the classification of Lp(a) was statistically significant (χ (2) = 28.33; P < 0,0001), with greater levels in subjects with this diagnosis. In the univariate analysis, subjects with each of the separate diagnostic criteria showed higher serum Lp(a) concentrations, except for hyperglycemia. CONCLUSIONS: Lp(a) values exhibit important variations regarding MS and each of its components. Impaired fasting glucose appeared as a protecting factor against elevated Lp(a) concentrations, whereas its association with LDL-C and hs-CRP suggests a potential pro-inflammatory role.

Lipoprotein(a): from molecules to therapeutics.

Lipoprotein (a) [Lp(a)] was discovered by Kare Berg in 1963 from the study of low-density lipoprotein genetic variants. Lp(a) contains a unique protein, apolipoprotein(a), which is linked to the Apo B-100 through a disulfide bond that gives it a great structural homology with plasminogen, and confers it atherogenic and atherothrombotic properties. Interest in Lp(a) has increased because an important association between high plasma levels of Lp(a) and coronary artery disease and cerebral vascular disorders has been demonstrated. Numerous case control studies have confirmed that hyper-Lp(a) is a risk factor for premature cardiovascular disease. Lp(a) is identified as a genetic trait with autosomal transmission, codified by one of the most studied polymorphic genes in humans. It has been demonstrated that variations in this gene are a major factor in the serum levels of Lp(a). Variations differ considerably between individuals and sex across populations. Various approaches to drug treatment using fibric acid derivatives, growth hormone, insulin-like growth factor-1, alcohol extracted soy protein, niacin, and exercise have been proven to decrease Lp(a) in high risk patients, but none has really been an effective therapeutic option for successfully reducing Lp(a) plasma levels.

Latent Autoimmune Diabetes in Adults: a case report.

Latent Autoimmune Diabetes in Adults (LADA) is an autoimmune endocrine disorder in which despite the presence of antipancreatic islets antibodies in the moment of diagnostics, the progression to beta-cell secretory insufficiency is slow. It is often confused with others types of diabetes and therefore the management is frequently inadequate. We report a clinical case of a 23-year-old man with diagnosis of type 2 diabetes since 6 months ago, poorly controlled with a sulfonylurea, who initially presented 2 months ago from polyuria, polydipsia, and asthenia and 6 kg weight loss. History of past illness was negative, however, his mother relates exclusive breastfeeding during the first 15 days of life and later (until the 6 months) he was fed with infant formula (S-26). Family history revealed a first-degree relative (father) with diabetes mellitus secondary to steroid administration due to diagnosis of bone marrow hypoplasia. Also presents second-degree family history (uncle and grandfather) of type 2 diabetes mellitus. There were no pathologic findings at the physical examination. Anthropometry and laboratory tests were as follows: body mass index (BMI) = 19.66 kg/m, basal and postprandial glycemia = 108, and 276 mg/dL respectively, glycated haemoglobin = 8.9%, basal and postprandial C-peptide (2 hours) = 1.9, and 3.2 ng/mL, homeostasis model assessment of beta cell function: 87.5%, homeostasis model assessment of insulin resistance: 1.6. LADA presumptive diagnosis was confirmed with presence of autoantibodies anti-tyrosin-phosphatase and GAD65. At the time of diagnosis, individuals with LADA present an onset age <50, BMI <25 kg/m2, low magnitude postprandial and basal hyperglycemia, normal or close to normal C-peptide values, and thus not occur with acute hyperglycemic crises. Insulin therapy preserves pancreatic b-cell function, at the point that eventually prescribed insulin doses need to be reduced.

The Maracaibo city metabolic syndrome prevalence study: design and scope.

The metabolic syndrome (MS) is a conglomerate of interrelated risk factors-including obesity, atherogenic dyslipidemia, arterial hypertension, and insulin resistance-which exponentially increase the risk of developing cardiovascular disease and type 2 diabetes mellitus. The purpose of this study was to determine the prevalence of MS according to the criteria published by the International Diabetes Federation, in individuals of both sexes over 18 years of age. This is a cross-sectional study based on MS prevalence in a representative sample from the Maracaibo district, Zulia State. The population of Maracaibo, according to the last census in 2001, was 1,219,927 habitants, with a 2007 population estimation of 1,428,043 habitants according to the National Institute of Statistics (NIS). Likewise, NIS projects that for the year 2009, 59.7% of the population of Venezuela will have individuals over 18 years of age. Using these data, the sample for Maracaibo District corresponds to 1986 individuals with or above 18 years of age. The data recollection was conducted by health professionals and medicine students, previously trained. The participants were subject to inquiry previous written consent and a medical examination, and qualitative variables such as smoking habit, socioeconomic status, physical activity, race, alcoholism, and nutritional habits, and quantitative ones like blood pressure, anthropometry, and blood works were determined. There is clear evidence that there is a lack of research and validated values to use as reference in our country and maybe in Latin America. Taking into account all that has been exposed here, this study will serve as a pilot for the numerous statistical determinations that will soon come afterward, providing first-hand accurate evidence on the behavior of the MS in the Latin American populace.

Homeostasis model assessment (HOMA) as surrogate insulinization criteria in patients with type 2 diabetes.

Type 2 diabetes mellitus is a metabolic disorder that results from defects in both insulin secretion and insulin action. Questions remain about when insulin therapy is indicated; thus, the aim of this study was to evaluate homeostasis model assessment beta-cell (HOMAbetacell) values as surrogate criteria for insulin therapy indication in patients with type 2 diabetes. A prospective study was performed involving 189 type 2 diabetic patients with deficient metabolic control assessed by clinical and laboratory parameters. All patients received nutritional intervention and combination therapy with metformin and glimepiride. Patients who did not respond were admitted to the next phase, which consisted of glimepiride + metformin + rosiglitazone oral therapy and revaluation after 3 months. Comparisons between responders and nonresponders in this phase were made in order to achieve differences in metabolic parameters and beta cell function. Of 189 patients studied, 150 (79.36%) were considered full responders in the first phase of this study. The remaining 39 patients were admitted in the second trial phase, in which 20 patients (51.28%) responded to triple oral therapy, while the other 19 (49.72%) required insulin therapy. Significant differences were found in fasting and postprandial glycemia (P < 0.001; P < 0.004) between the non-insulin-requiring group (200 +/- 12.0 mg/dL; 266.05 +/- 17,67 mg/dL) and the insulin-requiring group (291.5 +/- 17.6 mg/dL; 361.6 +/- 26.1 mg/dL). Likewise, significant differences were observed in homeostasis model assessment insulin resistance (HOMAIR) and HOMAbetacell values (P < 0.002; P < 0.04) between non-insulin-requiring patients (7.7 +/- 0.8; 24.5 +/- 1.3%) and insulin-requiring patients (12.6 +/- 1.2; 19.4 +/- 2.4%). Finally, significant differences were observed when comparing body mass index (non-insulin-requiring group, 29.2 +/- 0.4 kg/m, versus insulin-requiring group, 27.1 +/- 0.9 kg/m; P < 0.05). HOMAbetacell determination in clinical practice is a useful tool to determine when insulin therapy should be started for type 2 diabetic patients.

Tratamiento farmacólogico de la obesidad: presente, pasado y futuro / Treatment pharmacologic of the obesity: present, past and future

La obesidad es una enfermedad endocrino-metabólica caracterizada por excesiva acumulación de grasa en el tejido adiposo. La importancia en el estudio y tratamiento de la obesidad, radica no sólo en la alta incidencia de ésta patología en los últimos años, sino el alto riesgo en salud que ésta implica. El objetivo del tratamiento es revertir el balance energético positivo, y mejoramiento de las co-morbilidades asociadas, mediante la reducción de la ingesta de alimentos y el aumento del gasto energético. Los pilares de la terapéutica son modificar la conducta, dieta y ejercicios. Sin embargo estas no son herramientas que garantizan el mantenimiento de la pérdida de peso a largo plazo sin efecto rebote. Los fármacos constituyen una herramienta empleada en asociación con los anteriores y no como única medida. Los fármacos para el tratamiento de la obesidad, se clasifican en aquellos que reducen la ingesta de alimentos (agentes noradrenérgicos, serotoninérgicos y duales), disminuyen la absorción (orlistat) y los que incrementan la termogénesis (efedrina y cafeína). En la actualidad sólo sibutramina y orlistat se vislumbran como las únicas drogas cuya seguridad y eficacia demostrada permiten su aplicación clínica a largo plazo (2 años). Los avances en el estudio del balance energético y su regulación han postulado nuevos blancos para la fabricación de futuros fármacos más espec¡ficos y eficaces como los antagonistas de receptores endocanabinoides.

Inicio de la cardiología en Venezuela / The beginning of cardiology in Venezuela

La cardiología, previamente establecidas sus bases entre los siglos XVI y XX, se inicia en 1920, cuando por primera vez aparece el vocablo "cardiología" como título de la revista Archivos de Cardiología y Hematología, fundada por Pitaluga y Galandre, en España. En venezuela la inicia, en 1925, el doctor Heberto Cuenca Carrujo, en Maracaibo, la cual continúa en Caracas, de 1931 a 1938. Cuenca regenta la cátedra de Medicina Interna (UCV), desde 1935, y fue Jefe del Servicio de Medicina (Hospital Vargas, 1936). Continuaron los doctores Gustavo Plaza Izquierdo como jefe de la cátedra de Cardiología (1936), y Bernardo Gómez desde 1937. Este, posteriormente, inicia la estructuración de las instituciones cardiológicas básicas del país, campaña a la cual se incorporó el doctor Carlos Gil Yepez. Cuenca público noventa trabajos de investigación clínica, treinta de ellos sobre la cardiología: isquemia, arritmias, electrocardiografía, radiología, congénitas, miocardiopatías y corazon en deportes, publicados en: 1. Revista de la Sociedad Médico-Quirúrgica del Zulia. 2. Gaceta Médica de Caracas. 3. Archivos Venezolanos de Cardiológía y Hematología, esta última, fundada y editada por él, en 1935, la cual constituyó la primera revista cardiológica venezolana. La primera investigación, en 1927, versó sobre electrocardiografía

Enfermedad periodontal como factor de riesgo para la aterosclerosis / Periodontal disease with risk factor for the atherosclerosis

La asociación entre enfermedad periodontal y la aterosclerosis ha sido sustentada gracias a varios postulados en los cuales proceso inflamatorio característico de ambas entidades pudiera ser el nexo que explique por que es frecuente que estas patologías compartan rasgos patogénicos, clínicos, y fisiopatológicos. La asociación propuesta entre ambas está ligada a los efectos sistémicos de los lipopolisacáridos bacterianos liberados en el sitio de inflamación periodontal viajando por vía circulatoria para anclarse en el sub-endotelio de la íntima lo cual conduce a la sobre-expresión de moléculas de adherencia por parte de la célula endotelial, permitiendo la fijación y la entrada de monocitos al sub-endotelio. Esta interacción estimula la unión de los LPS a receptores específicos en la superficie de los monocitos y macrófagos desencadenando la liberación de citoquinas como el TNF-& e interleuquina-1 quienes amplifican la respuesta inflamatoria inicial. Además de ocasionar disfunción endotelial, infiltración laucocitaria y profileración de células musculares lisas, todos elementos característicos del fenómeno aterogénico. Los tóxicos bacterianos como los LPS, ácidos orgánicos de bajo peso molecular, aminas y leucotoxinas inician y perpetúan una serie de eventos inmunológicos en el hospedador que pueden ser divididos en fenómeno de tipo local como la enfermedad periodontal y distancia fenómeno aterogénico