Browsing by Author "Olmos, Pablo"

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    C(-106)T polymorphism of the aldose reductase gene and the progression rate of diabetic retinopathy
    (ELSEVIER IRELAND LTD, 2006) Olmos, Pablo; Bastias, Maria Juliana; Vollrath, Valeska; Toro, Luis; Trincado, Arturo; Salinas, Pablo; Claro, Juan Carlos; Lopez, Jose Manuel; Acosta, Ana Maria; Miquel, Juan Francisco; Castro, Juan
    Purpose: To study the C(-106)T polymorphism in the promoter of the aldose reductase (ALR2) gene: (a) its local prevalence and (b) its modulation of the susceptibility for developing retinopathy.
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    Differences in acute lung response to elastase instillation in two rodent species may determine differences in severity of emphysema development
    (AMER PHYSIOLOGICAL SOC, 2011) Vecchiola, Andrea; Francisco de la Llera, Juan; Ramirez, Rodrigo; Olmos, Pablo; Herrera, Cristobal I.; Borzone, Gisella
    Vecchiola A, de la Llera JF, Ramirez R, Olmos P, Herrera CI, Borzone G. Differences in acute lung response to elastase instillation in two rodent species may determine differences in severity of emphysema development. Am J Physiol Regul Integr Comp Physiol 301: R148-R158, 2011. First published April 13, 2011; doi:10.1152/ajpregu.00133.2011.-Elastase intratracheal instillation induces early emphysema in rodents. However, Syrian Golden hamsters develop more severe emphysema than Sprague-Dawley rats. We have reported species differences in oxidant/antioxidant balance modulating antiprotease function early after instillation. We now hypothesize that other components of the initial lung response to elastase might also be species-dependent. Sprague-Dawley rats and Syrian Golden hamsters received a single dose of pancreatic elastase (0.55 U/100 g body wt) to study acute lung injury biomarkers. Using serum, lung, and bronchoalveolar lavage fluid (BALF) samples, we evaluated changes in alveolar-capillary permeability, alpha 1-antitrypsin (alpha(1)-AT) concentration and activity, glutathione content, and proinflammatory cytokines. Rats showed a large increase in alveolar-capillary permeability and few hemorrhagic changes, whereas hamsters exhibited large hemorrhagic changes (P < 0.01) and mild transendothelial passage of proteins. Western blots showed a 30-fold increase in BALF alpha(1)-AT concentration in rats and only a 7-fold increase in hamsters (P < 0.001), with [alpha(1)-AT-elastase] complexes only in rats, suggesting differences in antiprotease function. This was confirmed by the alpha(1)-AT bioassay showing 20-fold increase in alpha(1)-AT activity in rats and only twofold increase in hamsters (P < 0.001). In rats, results were preceded by a 3-, 60-, and 20-fold increase in IL-6, IL-1 beta, and TNF-alpha respectively (P < 0.001). In hamsters, only IL-1 beta and TNF-alpha showed mild increases. All parameters studied were back to baseline by 4 days. In conclusion, several components of the initial lung response showed species differences. Cytokine release pattern and functional inhibition of alpha(1)-AT were the most significant components differing among species and could account for differences in susceptibility to elastase.
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    Rat and hamster species differences in susceptibility to elastase-induced pulmonary emphysema relate to differences in elastase inhibitory capacity
    (AMER PHYSIOLOGICAL SOC, 2007) Borzone, Gisella; Liberona, Leonel; Olmos, Pablo; Saez, Claudia; Meneses, Manuel; Reyes, Tatiana; Moreno, Rodrigo; Lisboa, Carmen
    Syrian Golden hamsters develop severe emphysema after a single intratracheal dose of elastase, whereas Sprague- Dawley rats exhibit mild emphysema with the same dose per kilogram body weight. We hypothesized that the development of severe emphysema is prevented in rats by the high serum level of alpha 1- antitrypsin reported in rats, compared with hamsters, which provides for a high lung elastase inhibitory capacity ( EIC). To explore this possibility, we challenged the antiprotease system of the rats by treating them with three similar weekly doses of elastase. Four months after treatment, we evaluated changes in histology, volume, and elastic properties of rat lungs and compared them with those of hamsters receiving a single dose of elastase. We also measured serum alpha 1- antitrypsin levels and serum and lung EIC in control rats and hamsters. Results showed that, in association with 40% less serum and lung EIC compared with rats ( P < 0.001), hamster lungs had upperlobe bullae formation, severe microscopic emphysema, a fourfold increase in lung volume ( P < 0.01) and a threefold increase in constant k, an index of compliance, of the lung deflation pressurevolume curve ( P < 0.01). In contrast, rats developed mild emphysema, with only 50% increase in volume ( P < 0.05) and 60% increase in constant k ( P < 0.01). In conclusion, two species that differ in serum and lung EIC exhibit significant differences in emphysema development after elastase. Rats with high EIC, despite receiving three doses of elastase, showed significantly less derangement of morphological and physiological parameters than hamsters with low EIC receiving a single dose.
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    Similar Metabolic Health in Overweight/Obese Individuals With Contrasting Metabolic Flexibility to an Oral Glucose Tolerance Test
    (FRONTIERS MEDIA SA, 2021) Fernandez Verdejo, Rodrigo Esteban; Malo Vintimilla, Maria Lorena; Gutierrez Pino, Juan; Lopez Fuenzalida, Antonio Eduardo; Olmos, Pablo; Irarrazaval Mena, Pablo; Galgani Fuentes, Jose Eduardo
    Background: Low metabolic flexibility (MetF) may be an underlying factor for metabolic health impairment. Individuals with low MetF are thus expected to have worse metabolic health than subjects with high MetF. Therefore, we aimed to compare metabolic health in individuals with contrasting MetF to an oral glucose tolerance test (OGTT).Methods: In individuals with excess body weight, we measured MetF as the change in respiratory quotient (RQ) from fasting to 1 h after ingestion of a 75-g glucose load (i.e., OGTT). Individuals were then grouped into low and high MetF (Low-MetF n = 12; High-MetF n = 13). The groups had similar body mass index, body fat, sex, age, and maximum oxygen uptake. Metabolic health markers (clinical markers, insulin sensitivity/resistance, abdominal fat, and intrahepatic fat) were compared between groups.Results: Fasting glucose, triglycerides (TG), and high-density lipoprotein (HDL) were similar between groups. So were insulin sensitivity/resistance, visceral, and intrahepatic fat. Nevertheless, High-MetF individuals had higher diastolic blood pressure, a larger drop in TG concentration during the OGTT, and a borderline significant (P = 0.05) higher Subcutaneous Adipose Tissue (SAT). Further, compared to Low-MetF, High-MetF individuals had an about 2-fold steeper slope for the relationship between SAT and fat mass index.Conclusion: Individuals with contrasting MetF to an OGTT had similar metabolic health. Yet High-MetF appears related to enhanced circulating TG clearance and enlarged subcutaneous fat.