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Exposure to ambient air particulate matter (PM) is associated with increased cardiorespiratory morbidity and mortality. In this context, alveolar macrophages exhibit proinflammatory and oxidative responses as a result of the clearance of particles, thus contributing to lung injury. However, the mechanisms linking these pathways are not completely clarified. Therefore, the oxinflammation phenomenon was studied in RAW 264.7 macrophages exposed to Residual Oil Fly Ash (ROFA), a PM surrogate rich in transition metals. While cell viability was not compromised under the experimental conditions, a proinflammatory phenotype was observed in cells incubated with ROFA 100 µg/mL, characterized by increased levels of TNF-α and NO production, together with PM uptake. This inflammatory response seems to precede alterations in redox metabolism, characterized by augmented levels of H2O2, diminished GSH/GSSG ratio, and increased SOD activity. This scenario resulted in increased oxidative damage to phospholipids. Moreover, alterations in mitochondrial respiration were observed following ROFA incubation, such as diminished coupling efficiency and spare respiratory capacity, together with augmented proton leak. These findings were accompanied by a decrease in mitochondrial membrane potential. Finally, NADPH oxidase (NOX) and mitochondria were identified as the main sources of superoxide anion () in our model. These results indicate that PM exposure induces direct activation of macrophages, leading to inflammation and increased reactive oxygen species production through NOX and mitochondria, which impairs antioxidant defense and may cause mitochondrial dysfunction.

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Several epidemiological studies have shown a positive correlation between daily increases in airborne particulate matter (PM) concentration and the occurrence of respiratory and cardiovascular diseases. Transition metals present in air PM were associated with adverse health effects after PM exposure. The aim of this work was to study lung O2 metabolism after an acute exposure to transition metal-coated nanoparticles (NPs). Female Swiss mice (25g) were intranasally instilled with a suspension of silica NP containing Ni (II), Cd (II), Fe (III), or Cr (VI) at 0, 0.01, 0.05, 0.1, and 1.0mg metal/kg body weight. Lung O2 consumption was found to be significantly increased after the exposure to most doses of Ni-NP and Fe-NP, and the 0.05mg metal/kg body weight dose of Cr-NP, while no changes were observed for Cd-NP. Lucigenin chemiluminescence (as an indicator of NADPH oxidase (NOX) activity) was evaluated in lung homogenates. Only Ni-NP and Fe-NP have shown the ability to induce a significant increase in lucigenin chemiluminescence. In order to establish the possible occurrence of pulmonary oxidative stress, TBARS levels and the GSH/GSSG ratio were determined. The higher doses of Ni-NP and Fe-NP were able to induce an oxidative stress condition, as shown by changes in both TBARS levels and the GSH/GSSG ratio. Taken together, the present results show differential effects for all the metals tested. These findings emphasize the importance of transition metals present air PM in PM adverse health effects, and contribute to the understanding of the pathological mechanisms triggered by the exposure to environmental PM.

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Thioredoxin-1 maintains the cellular redox status and decreases the infarct size in ischemia/reperfusion injury. However, whether the increase of thioredoxin-1 expression or its lack of activity modifies the protection conferred by ischemic postconditioning has not been yet elucidated. The aim was to evaluate if the thioredoxin-1 overexpression enhances the posctconditioning protective effect, and whether the lack of the activity abolishes the reduction of the infarct size. Wild type mice hearts, transgenic mice hearts overexpressing thioredoxin-1, and a dominant negative mutant (C32S/C35S) of thioredoxin-1 were used. The hearts were subjected to 30min of ischemia and 120min of reperfusion (Langendorff) (I/R group) or to postconditioning protocol (PostC group). The infarct size in the Wt-PostC group decreased in comparison to the Wt-I/R group (54.6±2.4 vs. 39.2±2.1%, p<0.05), but this protection was abolished in DN-Trx1-PostC group (49.7±1.1%). The ischemia/reperfusion and postconditioning in mice overexpressing thioredoxin-1 reduced infarct size at the same magnitude (35.9±2.1 and 38.4±1.3%, p<0.05 vs. Wt-I/R). In Wt-PostC, Trx1-I/R and Trx1- PostC, Akt and GSK3ß phosphorylation increased compared to Wt-I/R, without changes in DN-Trx1 groups. In conclusion, given that the cardioprotection conferred by thioredoxin-1 overexpression and postconditioning, is accomplished through the activation of the Akt/GSK3ß survival pathway, no synergic effect was evidenced. Thioredoxin-1 plays a key role in the postconditioning, given that when this protein is inactive the cardioprotective mechanism was abolished. Thus, diverse comorbidities or situations modifying the thioredoxin activity, could explain the absence of this strong mechanism of protection in different clinical situations.

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Thioredoxin-1 (Trx-1) is part of an antioxidant system that maintains the cell redox homeostasis but their role on ischemic postconditioning (PostC) is unknown. The aim of this work was to determine whether Trx-1 participates in the cardioprotective mechanism of PostC in young, middle-aged, and old mice. Male FVB young (Y: 3 month-old), middle-aged (MA: 12 month-old), and old (O: 20 month-old) mice were used. Langendorff-perfused hearts were subjected to 30 min of ischemia and 120 min of reperfusion (I/R group). After ischemia, we performed 6 cycles of R/I (10 s each) followed by 120 min of reperfusion (PostC group). We measured the infarct size (triphenyltetrazolium); Trx-1, total and phosphorylated Akt, and GSK3ß expression (Western blot); and the GSH/GSSG ratio (HPLC). PostC reduced the infarct size in young mice (I/R-Y: 52.3 ± 2.4 vs. PostC-Y: 40.0 ± 1.9, p < 0.05), but this protection was abolished in the middle-aged and old mice groups. Trx-1 expression decreased after I/R, and the PostC prevented the protein degradation in young animals (I/R-Y: 1.05 ± 0.1 vs. PostC-Y: 0.52 ± .0.07, p < 0.05). These changes were accompanied by an improvement in the GSH/GSSG ratio (I/R-Y: 1.25 ± 0.30 vs. PostC-Y: 7.10 ± 2.10, p < 0.05). However, no changes were observed in the middle-aged and old groups. Cytosolic Akt and GSK3ß phosphorylation increased in the PostC compared with the I/R group only in young animals. Our results suggest that PostC prevents Trx-1 degradation, decreasing oxidative stress and allowing the activation of Akt and GSK3ß to exert its cardioprotective effect. This protection mechanism is not activated in middle-aged and old animals.

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UNLABELLED: A Trichobezoar is a rare tumoral mass of the gastrointestinal tract, formed mainly from the ingestion of hair. It contains also mucus and foods debris. CASE PRESENTATION: A 22 years old female with a 10 years history of surgery secondary to gastric foreign body (trichobezoar), presents with abdominal pain, swelling, nausea and vomiting. Physical examination of the abdomen revealed a palpable mass in the epigastric and left upper quadrant regions. It was also noted areas of alopecia of the scalp. DISCUSSION: Ninety percent of the trichobezoars present in females with a high frequency between 10-19 years. The treatment of bezoars (unless small in size) is mainly surgical. A psychiatric evaluation and follow up is important after surgery hence in most cases there is a psychological disorder that lead to the ingestion of hair.

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El tricobezoar es una rara formación tumoral gástrica causada por un cuerpo extraño compuesto fundamentalmente por pelo; también contiene moco y fragmentos de alimentos. Presentación del caso: Paciente de 22 años que hace 10 años fue intervenida por cuerpo extraño gástrico (tricobezoar), ahora refiere cuadro de dolor abdominal, distensión, náuseas y vómitos, al examen físico presencia de masa abdominal palpable en epigástrico y cuadrante superior izquierdo. En la cabeza se observaron zonas alopécicas. Discusión: El 90% de los tricobezoares se presentan en el sexo femenino. Su máxima frecuencia es entre 10 y 19 años. El tratamiento de los bezoares, excepto los más pequeños, es quirúrgico. El control psiquiátrico postoperatorio es fundamental ya que en casi todos los casos existe en el fondo un conflicto afectivo que perpetúa el hábito de ingerir cabello.

A Trichobezoar is a rare tumoral mass of the gastrointestinal tract, formed mainly from the ingestion of hair. It contains also mucus and foods debris. Case presentation: A 22 years old female with a 10 years history of surgery secondary to gastric foreign body (trichobezoar), presents with abdominal pain, swelling, nausea and vomiting. Physical examination of the abdomen revealed a palpable mass in the epigastric and left upper quadrant regions. It was also noted areas of alopecia of the scalp. Discussion: Ninety percent of the trichobezoars present in females with a high frequency between 10 - 19 years. The treatment of bezoars (unless small in size) is mainly surgical. A psychiatric evaluation and follow up is important after surgery hence in most cases there is a psychological disorder that lead to the ingestion of hair.

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