The Effects of Dexamethasone and L-NAME on Acute Lung Injury in Rats with Lung Contusion.

The therapeutic efficiency of an anti-inflammatory agent, dexamethasone (DXM), and a nitric oxide synthase (NOS) inhibitor, Nitro-L-arginine methyl ester (L-NAME), in lung tissue injury after lung contusion was investigated. Serum levels of tumor necrosis factor-alpha (TNF-α), interleukin-10 (IL-10), YKL-40, an inflammatory peptide, inducible NOS (iNOS), and Clara cell protein 16 (CC-16) were evaluated. Immunohistochemical analyses were also performed, and the lung tissue was examined histopathologically. The study consisted of eight groups of Sprague-Dawley rats (n = 10 in each group), weighing 250-300 g: (1) control, (2) contusion, (3) control + DXM, (4) contusion + DXM, (5) control + L-NAME (6) contusion + L-NAME, (7) control + DXM + L-NAME, and (8) contusion + DXM + L-NAME. A previously developed lung contusion model was used, in addition to the control group. The rats were administered DXM and L-NAME intraperitoneally (i.p.) at doses of 15 and 60 mg/kg/day, respectively. DXM and L-NAME administration decreased the iNOS level in the contusion groups. DXM increased the levels of YKL-40 and IL-10 in both the control and contusion groups, with higher levels in the contusion groups. L-NAME increased the serum level of IL-10 in the lung contusion groups. DXM increased the synthesis of CC-16 in the control and contusion groups. The combined use of a high-dose steroid and NOS inhibitor resulted in the death of the rats. Steroids can increase the level of cytokines, such as YKL-40 and IL-10, and the synthesis of CC-16 and prevent pneumonia, ALI/ARDS, and sepsis in lung contusion.

Enhancement of clara cell 10-kD protein (CC10) production from nasal epithelial cells by fexofenadine hydrochloride.

BACKGROUND: Clara cell 10-kD protein (CC10) is well known to be an immuno-suppressive protein secreted from airway epithelial cells after inflammatory stimulation and is involved in the development of allergic disorders. Although histamine H1 receptor antagonists are used for the treatment of allergic disorders, the influence of the agents on CC10 production is not well understood. In the present study, we examined the influence of a histamine H1 receptor antagonist, fexofenadine hydrochloride (FEX) on CC10 production in vitro and in vivo. METHODS: Nasal epithelial cells (5 x 10(6) cells/ml) were stimulated with 20 ng/ml TNF-alpha in the presence of various concentrations of FEX for 24 hours. CC10 levels in culture supernatants were examined by ELISA. Patients with Japanese cedar pollinosis were treated orally with FEX twice a day at a single dose of 60 mg for two weeks during Japanese cedar pollen season (February 2011 to April 2011). CC10 levels in nasal secretions were also examined by ELISA. RESULTS: The addition of FEX into cell cultures caused increase in CC10 production induced by TNF-alpha stimulation, and the minimum concentration that caused significant increase was 200 ng/ml. Oral administration of FEX also increased CC10 levels in nasal secretions from pollinosis patients along with attenuation of clinical symptoms. CONCLUSION: The ability of FEX to enhance CC10 production may account, at least in part, for the clinical efficacy of the agent in allergic disorders, including allergic rhinitis.

Nasal epithelium integrity, environmental stressors, and allergic sensitization: a biomarker study in adolescents.

Changes in the airways epithelium caused by environmental insults might play a role in the development of allergic rhinitis. We measured albumin and Clara cell protein (CC16) in the nasal lavage fluid (NALF) from 474 adolescents (263 girls and 211 boys). The NALF CC16/albumin ratio, integrating the permeability and cellular integrity of the nasal epithelium, decreased mostly with time spent in chlorinated pools. In boys, a lower CC16/albumin ratio in NALF was associated with an increased risk of house dust mite sensitization. The results suggest that the CC16/albumin ratio in NALF can be used to detect nasal epithelium alterations linked to allergic sensitization.

Polydatin up-regulates Clara cell secretory protein to suppress phospholipase A2 of lung induced by LPS in vivo and in vitro.

BACKGROUND: Lung injury induced by lipopolysaccharide (LPS) remains one of the leading causes of morbidity and mortality in children. The damage to membrane phospholipids leads to the collapse of the bronchial alveolar epithelial barrier during acute lung injury (ALI)/acute respiratory distress syndrome (ARDS). Phospholipase A2 (PLA2), a key enzyme in the hydrolysis of membrane phospholipids, plays an important traumatic role in pulmonary inflammation, and Clara cell secretory protein (CCSP) is an endogenous inhibitor of PLA2. Our previous study showed that polydatin (PD), a monocrystalline extracted from a traditional Chinese medicinal herb (Polygonum cuspidatum Sieb, et Zucc), reduced PLA2 activity and sPLA2-IIA mRNA expression and mitigated LPS-induced lung injury. However, the potential mechanism for these effects has not been well defined. We have continued to investigate the effect of PD on LPS-induced expression of CCSP mRNA and protein in vivo and in vitro. RESULTS: Our results suggested that the CCSP mRNA level was consistent with its protein expression. CCSP expression was decreased in lung after LPS challenge. In contrast, PD markedly increased CCSP expression in a concentration-dependent manner. In particular, CCSP expression in PD-pretreated rat lung was higher than in rats receiving only PD treatment. CONCLUSION: These results indicated that up-regulation of CCSP expression causing inhibition of PLA2 activation may be one of the crucial protective mechanisms of PD in LPS-induced lung injury.

Proteomic bronchiolitis obliterans syndrome risk monitoring in lung transplant recipients.

BACKGROUND: Obliterative bronchiolitis poses a primary obstacle for long-term survival of lung transplant recipients and manifests clinically as bronchiolitis obliterans syndrome (BOS). Establishing a molecular level screening method to detect BOS-related proteome changes before its diagnosis by forced expiratory volume surrogate marker criteria was the main objective of this study. METHODS: Bronchoalveolar lavage was performed in 82 lung transplant recipients (48/34 with/without known BOS development) at different time points between 12 and 48 months after lung transplantation. A mass spectrometry-based method was devised to generate bronchoalveolar lavage fluid proteome profiles that were screened for BOS-specific alterations. Statistically significant marker peptides and proteins were identified and validated by in-gel digestion, tandem mass spectrometric sequencing, and quantitative immunoassays. RESULTS: Among the panel of statistically significant markers were Clara cell protein, calgranulin A, human neutrophil peptides, and the antimicrobial agent histatin. To assess their clinical relevance, a highly sensitive and specific classifier model was developed. Positive BOS classification by monitoring of seven polypeptides correlated strongly with a significant decrease in BOS-free time. Thus, it was possible to detect high-risk patients early on in the pathogenetic process. CONCLUSIONS: Monitoring the bronchoalveolar lavage fluid levels of seven polypeptides detected by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry allows a reliable prediction of early BOS using a Random Forest decision tree-based classifier model. The high accuracy of this robust model and its synergistic potential in combination with established forced expiratory volume-based diagnostics could make it an effective tool to supplement the current diagnostic regime after multicentric validation.

Lung permeability, antioxidant status, and NO2 inhalation: a selenium supplementation study in rats.

Little is known about antioxidant status, selenium status in particular, and lung response to NO2, which acts as a proinflammatory air pollutant. The effects of a low selenium diet (1.3 microg Se/d) with or without selenium supplementation were therefore studied in 128 Wistar rats, 2 mo old, male exposed to either acute (50 ppm, 30 min), intermittent subacute (5 ppm, 6 h/d, 5 d), intermittent long-term NO2 (1 ppm, 10 ppm, 6 h/d, 5 d/wk, 28 d), or normal atmospheric air (controls). Following sacrifice, measurements of lipid peroxidation (thiobarbituric acid-reactive substances, chemiluminescence), antioxidative protective enzymes (glutathione peroxidase [GPx], superoxide dismutase [SOD], glutathione S-transferase [GST], ceruloplasmin), lung damage (lactate dehydrogenase, alkaline and acid phosphatases), lung permeability (total protein, albumin), and inflammation (cell populations), along with the determination of new biomarkers such as CC16 (Clara-cell protein), were performed in serum and bronchoalveolar lavage fluid (BALF). While selenium-supplemented animals had increased GPx activity in serum prior to inhalation experiments, they also had decreased BALF CC16, blood SOD, and GST levels. Nevertheless, the protective role of normal selenium status with respect to NO2 lung toxicity was evident both for long-term and acute exposures, as the increase in BALF total proteins and corresponding decrease in serum (indicating increased lung permeability) was significantly more pronounced in selenium-deficient animals. During the various inhalation experiments, serum CC16 demonstrated its key role as an early marker of increased lung permeability. These findings corroborate the important role of selenium status in NO2 oxidative damage modulation, but also indicate, in view of its negative impact on CC16, a natural anti-inflammatory and immunosuppressor, that caution should be used prior to advocating selenium supplementation.

Low levels of CC16 in nasal fluid of children with birch pollen-induced rhinitis.

BACKGROUND: Clara cell protein 16 (CC16; secretoglobin 1A1) is an anti-inflammatory protein mainly expressed in the epithelial cells in the airways. OBJECTIVE: To compare the levels of CC16 in nasal lavage (NAL) from children with intermittent allergic rhinitis and healthy controls and to study the effect of a local steroid. METHODS: Thirty schoolchildren with birch pollen allergy and 30 healthy controls from the same schools were included in the study. The NAL fluid was collected before the season, during the birch pollen season and, for the patients, after 1 week of treatment with a local steroid. Symptom scores were obtained on every occasion. CC16 and eosinophil cationic protein (ECP) were analyzed with enzyme-linked immunosorbent assay. RESULTS: The nasal fluid levels of CC16 were significantly lower in patients than in controls, before and during pollen season. Before the season, the median CC16 concentrations were 9.1 (range 1.1-117) microg/l in patients and 25.7 (6.1-110.2) microg/l in controls. During the season, the median CC16 concentrations in nasal fluid were 12.9 (2.3-89.7) microg/l in the allergic children and 22.0 (9.5-90.1) microg/l in the healthy controls (P = 0.0005). Symptom scores, nasal fluid eosinophils and ECP were higher in patients during the season. Treatment with a local steroid did not change the CC16 levels. CONCLUSIONS: Nasal fluid CC16 levels were lower in children with birch pollen-induced allergic rhinitis than in healthy controls both before and during the pollen season. We speculate that reduction in anti-inflammatory activity by CC16 may contribute to the pathogenesis of allergic rhinitis.