Crocin "saffron" protects against beryllium chloride toxicity in rats through diminution of oxidative stress and enhancing gene expression of antioxidant enzymes.

Beryllium chloride (BeCl(2)) is a highly toxic substance that accumulates in different tissues after absorption. The purpose of this study was to investigate protective role of crocin against BeCl(2)-intoxication in rats. Male Wistar rats were used in this study and categorised into four groups (n=8). Group I served as normal control rats. Group II treated orally with BeCl(2) 86 mg/kg b.w. for five consecutive days. This dose was equivalent to experimental LD(50). Group III treated intraperitoneally with crocin 200 mg/kg b.w. for seven consecutive days. Group IV received crocin for seven consecutive days before BeCl(2) administration. Blood samples and liver and brain homogenates were obtained for haematological, biochemical and RT-PCR examinations. The haematocrit value, RBCs count and haemoglobin concentration were significantly decreased in BeCl(2)-treated rats. A significant increase was observed in rat liver and brain malondialdehyde level and protein carbonyls content in BeCl(2) exposed group compared to the control group, and these values were significantly declined upon administration of crocin. Lactate dehydrogenase levels in rat liver and brain significantly increased compared to the control group and was associated with significant decrease in catalase and superoxide dismutase activities. Reduced glutathione hepatic contents of BeCl(2)-treated rats were significantly decreased. There was significant decline in mRNA expression of catalase and superoxide dismutase genes in BeCl(2)-intoxicated rats compared to the normal rats. Crocin treatment prior to BeCl(2) intake resulted in significant increase in mRNA expressions of catalase and superoxide dismutase genes near to normalcy. The haematological and biochemical parameters were restored near to normal levels. Our results suggested that, BeCl(2) induced oxidation of cellular lipids and proteins and that administration of crocin reduced BeCl(2)-induced oxidative stress combined with initiation of mRNA expression of antioxidant genes.

Surfactant lipids regulate LPS-induced interleukin-8 production in A549 lung epithelial cells by inhibiting translocation of TLR4 into lipid raft domains.

In addition to providing mechanical stability, growing evidence suggests that surfactant lipid components can modulate inflammatory responses in the lung. However, little is known of the molecular mechanisms involved in the immunomodulatory action of surfactant lipids. This study investigates the effect of the lipid-rich surfactant preparations Survanta, Curosurf, and the major surfactant phospholipid dipalmitoylphosphatidylcholine (DPPC) on interleukin-8 (IL-8) gene and protein expression in human A549 lung epithelial cells using immunoassay and PCR techniques. To examine potential mechanisms of the surfactant lipid effects, Toll-like receptor 4 (TLR4) expression was analyzed by flow cytometry, and membrane lipid raft domains were separated by density gradient ultracentrifugation and analyzed by immunoblotting with anti-TLR4 antibody. The lipid-rich surfactant preparations Survanta, Curosurf, and DPPC, at physiological concentrations, significantly downregulated lipopolysaccharide (LPS)-induced IL-8 expression in A549 cells both at the mRNA and protein levels. The surfactant preparations did not affect the cell surface expression of TLR4 or the binding of LPS to the cells. However, LPS treatment induced translocation of TLR4 into membrane lipid raft microdomains, and this translocation was inhibited by incubation of the cells with the surfactant lipid. This study provides important mechanistic details of the immune-modulating action of pulmonary surfactant lipids.