Year in review 2009: Interstitial lung diseases, acute injury, sleep, physiology, imaging and bronchoscopic intervention

Abstract

Key words: acute lung injury, acute respiratory distress syndrome, asthma, endobronchial ultrasound, sleep apnoea. ACUTE LUNG INJURYAcute lung injury (ALI) and ARDS result in significant morbidity and mortality and are major contributors to admissions to intensive care units globally. Consequently, ALI and ARDS were the key themes explored in a number of papers published in Respirology during 2009. Treatment and prevention of acute lung injuryImproved understanding of the pathogenesis of ALI has lead to the development of a number of candidate therapies for the condition. Many basic science observations have, however, yet to be translated into effective treatment for ALI. In general, translational studies have focussed on two potential therapeutic strategies in ALI; the first involves prevention of ALI in these experiments by dosing with the candidate therapy before an insult known to induce lung injury. Such a therapeutic strategy might potentially be used clinically in patients undergoing high-risk surgery, for example, oesophagectomy. The alternative treatment approach has been to try and ameliorate and expedite the resolution of ALI once injury has occurred. Both of these treatment strategies, evaluated in animal models, have been the subjects of papers published in Respirology this year.Rong et al. 1 reported that prophylactic administration of Panax notoginseng saponins (PNS), an extract from the Chinese herb P. notoginseng that has previously been shown to have anti-inflammatory and anti-oxidant actions, alleviates ALI induced by intestinal ischaemia/reperfusion (I/R) injury in rats. The authors studied the effect of PNS in 4 groups of 12 rats; these rats either underwent sham operation and were given placebo or PNS (at a dose of 100 mg/kg) or received 1 h of intestinal ischaemia followed by 3 h of reperfusion and again were treated with either placebo or PNS before reperfusion. ALI was evaluated 3 h after the initiation of reperfusion. PNS-treated animals, in contrast to placebo-treated rats, showed little histological evidence of ALI following (I/R) and showed evidence of reduced inflammatory cell infiltrate in BAL fluid. PNS appeared to act, at least in part, by reducing oxidative stress in the lungs of animals suffering (I/R) injury.Wu et al. 2 by contrast looked at the effect of interleukin (IL)-10 in alleviating ALI by studying rats administered IL-10 following the induction of LPSinduced ALI. The rationale for exploring IL-10 as a potential treatment for ALI was the observation that endogenous IL-10 rises during the resolution phase of lung injury. Furthermore, in vitro, IL-10 reduces neutrophil activation. Interestingly, when administered to LPS-treated rats 12 h post induction of ALI, exogenous IL-10 reduced the severity of the lung injury response. This effect was, however, lost if the administration of IL-10 was delayed until 16 h, suggesting therefore that the therapeutic window of opportunity for treating evolving ALI is a narrow one. Risk factors for lung injury/pulmonary oedema/alveolar hae...

Study of the expression of GABAA receptor in rats during acute lung injury caused by endotoxin

“…GABA is the most important inhibitory neurotransmitter in the mammalian central nervous system and plays a central role in the mechanism of general anesthesia (Barbas, 2007;Tsushima et al, 2009;Eastwood et al, 2010). The effects of GABA signal transduction pathway activation on the central nervous system and the physiological and pathophysiological mechanisms has been focused in the anesthesia research.…”

“…Lung injury progression usually accompanies acute respiratory distress syndrome (ARDS) and acute lung injury (ALI), caused by trauma, shock and surgical infection (Barbas, 2007;Tsushima et al, 2009). ALI is a common clinical complication associated with excessive inflammatory response (EIR) and oxidative stress (OS)-mediated pathogenesis (Wheeler and Bernard, 2007;Eastwood et al, 2010).…”

“…However, the GABA/GABAR functions in respiratory and central nervous system were entirely different. In GABA signaling pathway, GABAR could be an active mediator in inflammatory response and in lung anti-injury procedure, which are involved in asthma pathogenesis, airway remodeling procedure, and regulation of lung homeostasis (Barbas, 2007;Tsushima et al, 2009;Eastwood et al, 2010).…”