Pterostilbene pre-treatment reduces LPS-induced acute lung injury through activating NR4A1.

CONTEXT: Pterostilbene (PTE), a common polyphenol compound, exerts an anti-inflammatory effect in many diseases, including acute lung injury (ALI). OBJECTIVE: This study explores the potential mechanism of PTE pre-treatment against lipopolysaccharide (LPS)-induced ALI. MATERIALS AND METHODS: Sixty Sprague-Dawley rats were divided into control, ALI, 10 mg/kg PTE + LPS, 20 mg/kg PTE + LPS, and 40 mg/kg PTE + LPS groups. At 24 h before LPS instillation, PTE was administered orally. At 2 h before LPS instillation, PTE was again administered orally. After 24 h of LPS treatment, the rats were euthanized. The levels of inflammatory cells and inflammatory factors in the bronchoalveolar lavage fluid (BALF), the expression of nuclear receptor subfamily 4 group A member 1 (NR4A1), and the nuclear factor (NF)-κB pathway-related protein levels were detected. NR4A1 agonist was used to further investigate the mechanism of PTE pre-treatment. RESULTS: After PTE pre-treatment, the LPS induced inflammation was controlled and the survival rate was increased to 100% from 70% after LPS treatment 24 h. For lung injury score, it decreased to 1.5 from 3.5 after treating 40 mg/kg PTE. Compared with the control group, the expression of NR4A1 in the ALI group was decreased by 20-40%. However, the 40 mg/kg PTE pre-treatment increased the NR4A1 expression by 20-40% in the lung tissue. The results obtained with pre-treatment NR4A1 agonist were similar to those obtained by pre-treatment 40 mg/kg PTE. CONCLUSIONS: PTE pre-treatment might represent an appropriate therapeutic target and strategy for preventing ALI induced by LPS.

[Spatiotemporal variability of soil fertility parameters in Xinhui District of Guangdong Province].

By the methods of geostatistics and GIS, this paper studied the spatial distribution patterns of pH, organic matter, total nitrogen (N) and total phosphorus (P) in cultivated soils of Xinhui District, Guangdong Province from 1982 to 2003. The paired samples t test and Kriging results showed that soil pH and organic matter content were significantly lower in 2003 than in 1982, while the contents of soil total N and total P were in adverse. The spatial distribution of test parameters changed to different degrees over the past 20 years. Soil pH tended to decrease in most areas of the study district, soil organic matter decreased except at the banks of Yinzhou Lake and parts of south and northwest, soil total N increased in most areas except the parts of east and northwest, and soil total P increased in most areas.