Glutamine Therapy Reduces Inflammation and Extracellular Trap Release in Experimental Acute Respiratory Distress Syndrome of Pulmonary Origin.

The innate immune response plays an important role in the pathophysiology of acute respiratory distress syndrome (ARDS). Glutamine (Gln) decreases lung inflammation in experimental ARDS, but its impact on the formation of extracellular traps (ETs) in the lung is unknown. In a mouse model of endotoxin-induced pulmonary ARDS, the effects of Gln treatment on leukocyte counts and ET content in bronchoalveolar lavage fluid (BALF), inflammatory profile in lung tissue, and lung morphofunction were evaluated in vivo. Furthermore, ET formation, reactive oxygen species (ROS) production, glutathione peroxidase (GPx), and glutathione reductase (GR) activities were tested in vitro. Our in vivo results demonstrated that Gln treatment reduced ET release (as indicated by cell-free-DNA content and myeloperoxidase activity), decreased lung inflammation (reductions in interferon-γ and increases in interleukin-10 levels), and improved lung morpho-function (decreased static lung elastance and alveolar collapse) in comparison with ARDS animals treated with saline. Moreover, Gln reduced ET and ROS formation in BALF cells stimulated with lipopolysaccharide in vitro, but it did not alter GPx or GR activity. In this model of endotoxin-induced pulmonary ARDS, treatment with Gln reduced pulmonary functional and morphological impairment, inflammation, and ET release in the lung.

Decreased PGC1- α levels and increased apoptotic protein signaling are associated with the maladaptive cardiac hypertrophy in hyperthyroidism.

Hyperthyroidism can lead to the activation of proteins which are associated with inflammation, apoptosis, hypertrophy, and heart failure. This study aimed to explore the inflammatory and apoptotic proteins involved in the hyperthyroidism-induced cardiac hypertrophy establishment. Male Wistar rats were divided into control and hyperthyroid (12 mg/L L-thyroxine, in drinking water for 28 days) groups. The expression of inflammatory and apoptotic signaling proteins was quantified in the left ventricle by Western blot. Hyperthyroidism was confirmed by evaluation of T3 and T4 levels, as well as cardiac hypertrophy development. There was no change in the expression of HSP70, HIF1-α, TNF-α, MyD88, p-NFκB, NFκB, p-p38, and p38. Reduced expression of p53 and PGC1-α was associated with increased TLR4 and decreased IL-10 expression. Decreased Bcl-2 expression and increased Bax/Bcl-2 ratio were also observed. The results suggest that reduced PGC1-α and IL-10, and elevated TLR4 proteins expression could be involved with the diminished mitochondrial biogenesis and anti-inflammatory response, as well as cell death signaling, in the establishment of hyperthyroidism-induced maladaptive cardiac hypertrophy.

Intravenous glutamine administration reduces lung and distal organ injury in malnourished rats with sepsis.

Malnutrition is a risk factor for infection, compromising immune response. Glutamine (Gln) protects the lungs and distal organs in well-nourished septic and nonseptic conditions; however, no study to date has analyzed the effects of Gln in the presence of sepsis and malnutrition. In the present work, we tested the hypothesis that early therapy with intravenous Gln prevents lung and distal organ damage in septic malnourished rats. Protein-energy malnutrition was induced in male Wistar rats for 4 weeks. At the end of 4 weeks, malnourished animals were assigned to a sepsis-inducing cecal ligation and puncture group or a sham surgery group. One hour after surgery, animals were given saline (Sal) or L-alanyl-L-glutamine (Gln) intravenously. In addition, a control group (C) was set up with rats fed ad libitum, not submitted to surgery or treatment. Forty-eight hours after surgery, in malnutrition-sham rats, Gln therapy lessened neutrophil lung infiltration and apoptosis in lung and liver. In malnutrition-cecal ligation and puncture rats, Gln therapy yielded (a) reduced static lung elastance, alveolar collapse, inflammation (neutrophil infiltration, interleukin 6), and collagen deposition; (b) repair of types I and II epithelial cells; (c) no significant changes in heat shock protein 70 expression or heat shock factor 1 phosphorylation; (d) a greater number of M1 and M2 macrophages in lung tissue; and (e) less apoptosis in the lung, kidney, small intestine, and liver. In conclusion, early therapy with intravenous Gln reduced inflammation, fibrosis, and apoptosis, minimizing lung and distal organ injury, in septic malnourished rats. These beneficial effects may be associated with macrophage activation in the lung.