The association between the size of adipocyte-derived extracellular vesicles and fasting serum triglyceride-glucose index as proxy measures of adipose tissue insulin resistance in a rat model of early-stage obesity.

Introduction: Obesity is a complex disease that predisposes individuals to cardiometabolic alterations. It leads to adipose tissue (AT) dysfunction, which triggers insulin resistance (IR). This suggests that people with obesity develop local IR first and systemic IR later. AT secretes extracellular vesicles, which may be physiopathologically associated with the development of IR. Our aim was to evaluate the effect of a high-fat diet on different parameters of adiposity in a rat model of early-stage obesity and to determine if these parameters are associated with markers of systemic IR. In addition, we sought to explore the relationship between fasting blood measures of IR (Triglycerides/High Density Lipoprotein-cholesterol [TAG/HDL-c] and Triglycerides-Glucose Index [TyG Index]) with the size of adipocyte-derived extracellular vesicles (adEV). Methods: We used a model of diet-induced obesity for ten weeks in Wistar rats exposed to a high-fat diet. Final weight gain was analyzed by Dual X-ray absorptiometry. Visceral obesity was measured as epididymal AT weight. IR was evaluated with fasting TyG Index & TAG/HDL-c, and adEV were isolated from mature adipocytes on ceiling culture. Results: In the high-fat diet group, glucose and triglyceride blood concentrations were higher in comparison to the control group (Log2FC, 0.5 and 1.5 times higher, respectively). The values for TyG Index and adEV size were different between the control animals and the high-fat diet group. Multiple linear regression analyses showed that adEV size can be significantly associated with the TyG Index value, when controlling for epididymal AT weight. Conclusion: Our results show that lipid and glucose metabolism, as well as the size and zeta potential of adEV are already altered in early-stage obesity and that adEV size can be significantly associated with liver and systemic IR, estimated by TyG Index.

An early prediction model for gestational diabetes mellitus based on metabolomic biomarkers.

BACKGROUND: Gestational diabetes mellitus (GDM) represents the main metabolic alteration during pregnancy. The available methods for diagnosing GDM identify women when the disease is established, and pancreatic beta-cell insufficiency has occurred.The present study aimed to generate an early prediction model (under 18 weeks of gestation) to identify those women who will later be diagnosed with GDM. METHODS: A cohort of 75 pregnant women was followed during gestation, of which 62 underwent normal term pregnancy and 13 were diagnosed with GDM. Targeted metabolomics was used to select serum biomarkers with predictive power to identify women who will later be diagnosed with GDM. RESULTS: Candidate metabolites were selected to generate an early identification model employing a criterion used when performing Random Forest decision tree analysis. A model composed of two short-chain acylcarnitines was generated: isovalerylcarnitine (C5) and tiglylcarnitine (C5:1). An analysis by ROC curves was performed to determine the classification performance of the acylcarnitines identified in the study, obtaining an area under the curve (AUC) of 0.934 (0.873-0.995, 95% CI). The model correctly classified all cases with GDM, while it misclassified ten controls as in the GDM group. An analysis was also carried out to establish the concentrations of the acylcarnitines for the identification of the GDM group, obtaining concentrations of C5 in a range of 0.015-0.25 µmol/L and of C5:1 with a range of 0.015-0.19 µmol/L. CONCLUSION: Early pregnancy maternal metabolites can be used to screen and identify pregnant women who will later develop GDM. Regardless of their gestational body mass index, lipid metabolism is impaired even in the early stages of pregnancy in women who develop GDM.

Extracellular Vesicles from Adipose Tissue Could Promote Metabolic Adaptation through PI3K/Akt/mTOR.

Extracellular vesicles (EVs) are nanoparticles secreted by cells under physiological and pathological conditions, such as metabolic diseases. In this context, EVs are considered potential key mediators in the physiopathology of obesity. It has been reported that EVs derived from adipose tissue (ADEVs) contribute to the development of a local inflammatory response that leads to adipose tissue dysfunction. In addition, it has been proposed that EVs are associated with the onset and progression of several obesity-related metabolic diseases such as insulin resistance. In particular, characterizing the molecular fingerprint of obesity-related ADEVs can provide a bigger picture that better reflects metabolic adaptation though PI3K/Akt/mTOR. Hence, in this review we describe the possible crosstalk communication of ADEVs with metabolically active organs and the intracellular response in the insulin signaling pathway.

Metabolic flexibility during normal pregnancy allows appropriate adaptation during gestation independently of BMI.

BACKGROUND & AIMS: Overweight and obesity in reproductive-age women hasten the development of insulin resistance and increase risk for deterioration of pregnancy metabolism. These pregnancy-associated metabolic changes are similar to those of the metabolic syndrome. Thus, some metabolic flexibility must allow appropriate adaptation to the metabolic load that pregnancy imposes. We evaluated metabolic flexibility during uncomplicated pregnancy in women with pre-gestational normal weight or overweight. METHODS: In 20 women with singleton pregnancies, pre-pregnancy BMI was categorized as normal-weight (Nw) or overweight (Ow). The women were seen quarterly, and fasting and postprandial blood samples were collected at each visit. Indirect fasting and/postprandial calorimetry was performed to evaluate metabolic flexibility (Δrespiratory quotient (RQ) = RQpostprandial - RQfasting). RESULTS: In the first trimester, metabolic flexibility was lower in the Ow group compared to the Nw group (0.031 ± 0.0131 vs 0.077 ± 0.018, respectively) without a statistically significant difference (p = 0.053). In the second trimester, the Ow group was significantly more flexible than the Nw group (0.190 ± 0.016 vs 0.077 ± 0.015, respectively (p = 0.004)). For the third trimester, the Ow and Nw groups did not differ in metabolic flexibility (0.074 ± 0.013 vs 0.087 ± 0.021, respectively) (p = 0.40). The most influential variables for metabolic flexibility during pregnancy were lactate, leptin, ß-hydroxybutyrate, glycerol, aromatic amino acids, medium and long chain acylcarnitine's. CONCLUSIONS: Our findings indicate that metabolic flexibility changes throughout pregnancy, independently of pre-pregnancy BMI. These changes maintain metabolic homeostasis between the mother and foetus, allowing for appropriate adjustments during pregnancy.

Comparison of the prevalence of sarcopenia using skeletal muscle mass index and calf circumference applying the European consensus definition in elderly Mexican women.

AIM: To compare the prevalence of sarcopenia using two indicators: skeletal muscle mass index (SMI) and calf circumference (CC) used in the algorithm proposed by the European Working Group on Sarcopenia in Mexican elderly women. METHODS: This was a cross-sectional study. Lean body mass was determined by dual-energy X-ray absorptiometry. To define sarcopenia, the SMI was obtained using a cut-off value of 5.5 kg/m2 , and the CC cut-off was 31 cm. For gait speed and handgrip strength, the cut-off values were 0.8 m/s and 20 kg, respectively. RESULTS: A total of 137 women (mean age 73.8 ± 6.7 years) participated in the study. The prevalence of sarcopenia was 14.6% using SMI and 11.0% using CC (P = 0.009). Body mass index was associated with a lower probability of sarcopenia applying SMI or CC (OR 0.75, P = 0.002 for SMI and OR 0.71, P = 0.004 for CC). Sarcopenia evaluated either with dual-energy X-ray absorptiometry or CC was not associated with physical performance, such as five times chair stand test, timed up and go test and short physical performance battery. Additionally, SMI was not associated with physical performance, five times chair stand test (P = 0.775) and timed up-and-go test (P = 0.341). CONCLUSIONS: The prevalence of sarcopenia in active elderly women was low. A higher prevalence of sarcopenia was detected using SMI compared with CC. It is important to identify the best methods to assess skeletal muscle mass to obtain a reliable diagnosis of sarcopenia. Geriatr Gerontol Int 2017; 17: 161-170.

A comparison of dual energy x-ray absorptiometry and two bioelectrical impedance analyzers to measure body fat percentage and fat-free mass index in a group of Mexican young women.

INTRODUCTION: Studies of obesity require the estimation of fat mass (FM) and fat-free mass (FFM); therefore it is important to validate methods that evaluate these measurements. OBJECTIVE: We sought to compare two different bioelectrical impedance analysis systems (BIAs) to estimate FM and FFM using dual-energy X-ray absorptiometry (DXA) as reference. METHODS: We used a cross-sectional design. We evaluated FM and FFM using DXA and two types of BIA equipment: a foot-foot system (FFS) and a hand-foot system (HFS). We conducted paired analysis (paired ttest). We used Bland-Altman plots to assess the relationships between FM and FFMI, limits of agreement were constructed (CL). RESULTS: A total of 175 female students (22.9 ± 2.2 years old) participated in the study. The paired analysis showed significant differences between the mean value of body fat percentage (BF%) estimated by BIA equipment compared to DXA (FFS = 28.7%, HFS= 34.4% and DXA= 35.3%). The mean difference between the HFS and DXA of BF% was -0.96, ((CL -5.29, 7.20). For the FFS, the mean difference was -6.69, (CL -0.29, -13.09). The paired analysis revealed significant differences between the estimates of FFMI by BIA compared to DXA (FFS =16.29, HFS =14.95, DXA =14.18). The mean difference between HFS and DXA was 0.78, and (CL -2.27, 0.72) whereas the FFS mean difference was -2.11 (CL -3.73 -0.49). CONCLUSION: A different magnitude of bias was observed between the BIA equipment arrays. The HFS appears to be more reliable than the FFS used, particularly in obtaining FFMI in young women.

Introducción: Los estudios de obesidad requieren estimación de masa grasa (FM) y masa libre de grasa (FFM). Objetivo: Comparar dos equipos de impedancia bioeléctrica (BIA) para estimar FM y FFM usando absorciometría de rayos X de energía dual (DXA) como referencia. Métodos: Estudio transversal. FM y FFM fueron evaluados por DXA y BIA: sistema pie-pie (FFS) y sistema mano-pie (HFS). Se realizaron pruebas t pareadas, coeficientes de correlación y análisis de Bland y Altman. Limites de acuerdo fueron calculados (CL). Resultados: Fueron estudiadas 175 mujeres (22,9 ± 2,2 años). Hubo diferencias significativas entre el promedio del porcentaje de grasa estimado por los equipos de BIA en comparación con DXA (FFS = 28,7%, HFS = 34,4% y DXA = 35,3%). La diferencia de medias del porcentaje de grasa entre HFS y DXA fue -0.96, (CL -5,29, 7,21). La diferencia de medias para FFS fue de -6,69,(CL -0,29, - 13.09) Hubo diferencias significativas entre las estimaciones de FFMI por BIA y DXA (FFS = 16,29, HFS = 14,95, DXA = 14,18). La diferencia de medias entre HFS y DXA fue = 0,78, (CL -2,27, 0,72) y la diferencia de medias de FFS fue -2,11: (CL -3,73 , -0,49). Conclusiones: Niveles diferentes de sesgo se observaron entre los equipos de BIA. El HFS parece ser más confiable que el FFS, sobre todo en la obtención de FFMI en mujeres jóvenes.

The relationship between sarcopenia,undernutrition, physical mobility and basic activities of daily living in a group of elderly women of Mexico City.

BACKGROUND: Sarcopenia is a geriatric syndrome, which affects the functional status and mobility of individuals. OBJECTIVE: To identify the prevalence of sarcopenia and undernutrition, and to assess the association between sarcopenia and mobility, and sarcopenia and basic activities of daily living (ADL) in a group of elderly women. SUBJECTS AND METHODS: A cross-sectional study was performed in patients attending a geriatric service at a government hospital in Mexico City. Sarcopenia was identified applying Baumgartner's equation by obtaining skeletal muscle mass index (SMI) and undernutrition was diagnosed using mini-nutritional assessment instrument (MNA). The SENECA questionnaire and Katz index were used to evaluate mobility and ADL, respectively. STATISTICAL ANALYSIS: lineal regression models were constructed fitting SMI as a dependent variable and SENECA, and ADL scores as independent variables, adjusted for age. RESULTS: 90 women with a mean age of 78.2 (± 6.8) were studied. Undernutrition was identified in 15.5% of the patients. The prevalence of sarcopenia was 41.1%. Patients with sarcopenia presented a high prevalence of undernutrition (p < 0.001). Sarcopenia was associated with difficulty in climbing stairs (OR = 2.63, p = 0.03), adjusted for age. The mobility score was associated with sarcopenia, in the group without sarcopenia the mean score was 16.3, and with sarcopenia it was 18.3, (p = 0.04). Regarding ADL, 64.9% of the patients with intermediate independence and dependence had sarcopenia, while 35.1% with total independence presented sarcopenia (p < 0.001). CONCLUSIONS: The elder women with sarcopenia had a higher prevalence of undernutrition. Sarcopenia was associated with difficulties in mobility, particularly difficulties in climbing stairs.

Antecedentes: La sarcopenia es un síndrome geriátrico que afecta el estado funcional y la movilidad de los ancianos. Objetivo: Identificar la prevalencia de sarcopenia y desnutrición, y evaluar la asociación entre sarcopenia y movilidad, y sarcopenia y actividades básicas de la vida diaria (ABVD), en un grupo de mujeres ancianas. Sujetos y métodos: Un estudio de corte transversal, fue llevado a cabo en pacientes que asistían a un servicio de geriatría en un hospital público en la ciudad de México. La sarcopenia fue identificada aplicando la ecuación de Baumgartner para obtener el índice de masa muscular esquelética apendicular (IMEA) y la desnutrición fue diagnosticada usando la evaluación mínima del estado de nutrición (MNA). El cuestionario de SENECA y el índice de Katz fueron usados para evaluar movilidad y ABVD, respectivamente. Análisis estadístico: un modelo de regresión lineal fue construido usando IMEA como variable dependiente y SENECA, y la calificación de ABVD como variables independientes, ajustado por edad. Resultados: 90 mujeres con un promedio de edad de 78,2 (± 6,8) AÑOs fueron estudiadas. La desnutrición fue identificada en 15,5% de las pacientes. La prevalencia de sarcopenia fue de 41,1%. Las pacientes con sarcopenia presentaron una alta prevalencia de desnutrición (p < 0,001). La sarcopenia se asoció con dificultad para subir escaleras (OR = 2,63, p = 0,03), ajustada por edad. La movilidad se asoció con sarcopenia; en el grupo sin sarcopenia el promedio de la escala fue 16,3, y con sarcopenia 18,3, (p = 0,04). En relación a ABVD, 64,9% de las pacientes con independencia intermedia/dependencia tenía sarcopenia, mientras que 35,1% con independencia total presentó sarcopenia, (p < 0,001). Conclusiones: Las pacientes con sarcopenia tenían una mayor prevalencia de desnutrición. La sarcopenia se asoció con dificultad para la movilidad, particularmente subir escaleras.

A comparison of dual energy X- ray absorptiometry and two bioelectrical impedance analyzers to measure body fat percentage and fat-free mass index in a group of Mexican young women / Comparación de la absorciometría de rayos x de energía dual y dos analizadores de impedancia bioeléctrica para medir el porcentaje de grasa corporal y el índice de masa libre de grasa en un grupo de mujeres jóvenes mexicanas

Introduction: Studies of obesity require the estimation of fat mass (FM) and fat-free mass (FFM); therefore it is important to validate methods that evaluate these measurements. Objective: We sought to compare two different bioelectrical impedance analysis systems (BIAs) to estimate FM and FFM using dual-energy X-ray absorptiometry (DXA) as reference. Methods: We used a cross-sectional design. We evaluated FM and FFM using DXA and two types of BIA equipment: a foot-foot system (FFS) and a hand-foot system (HFS). We conducted paired analysis (paired t test). We used Bland-Altman plots to assess the relationships between FM and FFMI, limits of agreement were constructed (CL) Results: A total of 175 female students (22.9 ± 2.2 years old) participated in the study. The paired analysis showed significant differences between the mean value of body fat percentage (BF %) estimated by BIA equipment compared to DXA (FFS = 28.7%, HFS= 34.4% and DXA= 35.3%). The mean difference between the HFS and DXA of BF % was -0.96, ((CL -5.29, 7.20). For the FFS, the mean difference was -6.69, (CL -0.29, -13.09). The paired analysis revealed significant differences between the estimates of FFMI by BIA compared to DXA (FFS =16.29, HFS =14.95, DXA =14.18). The mean difference between HFS and DXA was 0.78, and (CL -2.27, 0.72) whereas the FFS mean difference was -2.11 (CL -3.73 -0.49). Conclusion: A different magnitude of bias was observed between the BIA equipment arrays. The HFS appears to be more reliable than the FFS used, particularly in obtaining FFMI in young women (AU)

Introducción: Los estudios de obesidad requieren estimación de masa grasa (FM) y masa libre de grasa (FFM). Objetivo: Comparar dos equipos de impedancia bioeléctrica (BIA) para estimar FM y FFM usando absorciometría de rayos X de energía dual (DXA) como referencia. Métodos: Estudio transversal. FM y FFM fueron evaluados por DXA y BIA: sistema pie-pie (FFS) y sistema mano-pie (HFS). Se realizaron pruebas t pareadas, coeficientes de correlación y análisis de Bland y Altman. Limites de acuerdo fueron calculados (CL). Resultados: Fueron estudiadas 175 mujeres (22,9 ± 2,2 años). Hubo diferencias significativas entre el promedio del porcentaje de grasa estimado por los equipos de BIA en comparación con DXA (FFS = 28,7%, HFS = 34,4% y DXA = 35,3%). La diferencia de medias del porcentaje de grasa entre HFS y DXA fue -0.96, (CL -5,29, 7,21). La diferencia de medias para FFS fue de -6,69,(CL -0,29, - 13.09) Hubo diferencias significativas entre las estimaciones de FFMI por BIA y DXA (FFS = 16,29, HFS = 14,95, DXA = 14,18). La diferencia de medias entre HFS y DXA fue = 0,78, (CL -2,27, 0,72) y la diferencia de medias de FFS fue -2,11: (CL -3,73, -0,49). Conclusiones: Niveles diferentes de sesgo se observaron entre los equipos de BIA. El HFS parece ser más confiable que el FFS, sobre todo en la obtención de FFMI en mujeres jóvenes (AU)

The relationship between sarcopenia, undernutrition, physical mobility and basic activities of daily living in a group of elderly women of Mexico City / Relación entre sarcopenia, desnutrición, movilidad física y actividades básicas de la vida diaria en un grupo de ancianas de la Ciudad de México

Background: Sarcopenia is a geriatric syndrome, which affects the functional status and mobility of individuals. Objective: To identify the prevalence of sarcopenia and undernutrition, and to assess the association between sarcopenia and mobility, and sarcopenia and basic activities of daily living (ADL) in a group of elderly women. Subjects and methods: A cross-sectional study was performed in patients attending a geriatric service at a government hospital in Mexico City. Sarcopenia was identified applying Baumgartner's equation by obtaining skeletal muscle mass index (SMI) and undernutrition was diagnosed using mininutritional assessment instrument (MNA). The SENECA questionnaire and Katz index were used to evaluate mobility and ADL, respectively. Statistical analysis: lineal regression models were constructed fitting SMI as a dependent variable and SENECA, and ADL scores as independent variables, adjusted for age. Results: 90 women with a mean age of 78.2 (± 6.8) were studied. Undernutrition was identified in 15.5% of the patients. The prevalence of sarcopenia was 41.1%. Patients with sarcopenia presented a high prevalence of undernutrition (p < 0.001). Sarcopenia was associated with difficulty in climbing stairs (OR = 2.63, p = 0.03), adjusted for age. The mobility score was associated with sarcopenia, in the group without sarcopenia the mean score was 16.3, and with sarcopenia it was 18.3, (p = 0.04). Regarding ADL, 64.9% of the patients with intermediate independence and dependence had sarcopenia, while 35.1% with total independence presented sarcopenia (p < 0.001). Conclusions: The elder women with sarcopenia had a higher prevalence of undernutrition. Sarcopenia was associated with difficulties in mobility, particularly difficulties in climbing stairs (AU)

Antecedentes: La sarcopenia es un síndrome geriátrico que afecta el estado funcional y la movilidad de los ancianos. Objetivo: Identificar la prevalencia de sarcopenia y desnutrición, y evaluar la asociación entre sarcopenia y movilidad, y sarcopenia y actividades básicas de la vida diaria (ABVD), en un grupo de mujeres ancianas. Sujetos y métodos: Un estudio de corte transversal, fue llevado a cabo en pacientes que asistían a un servicio de geriatría en un hospital público en la ciudad de México. La sarcopenia fue identificada aplicando la ecuación de Baumgartner para obtener el índice de masa muscular esquelética apendicular (IMEA) y la desnutrición fue diagnosticada usando la evaluación mínima del estado de nutrición (MNA). El cuestionario de SENECA y el índice de Katz fueron usados para evaluar movilidad y ABVD, respectivamente. Análisis estadístico: un modelo de regresión lineal fue construido usando IMEA como variable dependiente y SENECA, y la calificación de ABVD como variables independientes, ajustado por edad. Resultados: 90 mujeres con un promedio de edad de 78,2 (± 6,8) años fueron estudiadas. La desnutrición fue identificada en 15,5% de las pacientes. La prevalencia de sarcopenia fue de 41,1%. Las pacientes con sarcopenia presentaron una alta prevalencia de desnutrición (p < 0,001). La sarcopenia se asoció con dificultad para subir escaleras (OR = 2,63, p = 0,03), ajustada por edad. La movilidad se asoció con sarcopenia; en el grupo sin sarcopenia el promedio de la escala fue 16,3, y con sarcopenia 18,3, (p = 0,04). En relación a ABVD, 64,9% de las pacientes con independencia intermedia/dependencia tenía sarcopenia, mientras que 35,1% con independencia total presentó sarcopenia, (p < 0,001). Conclusiones: Las pacientes con sarcopenia tenían una mayor prevalencia de desnutrición. La sarcopenia se asoció con dificultad para la movilidad, particularmente subir escaleras (AU)