25 research outputs found
TOTAL ANTIOXIDANT CAPACITY AND ANTIHYPERLIPIDEMIC ACTIVITY OF ALKALOID EXTRACT FROM AERIAL PART OF ANETHUM GRAVEOLENS L. PLANT
Compounds of pharmacological interest (alkaloids) were extracted and the results revealed that the extract consist of three alkaloid compounds (A, B & C). Compound (A) has been isolated from Anethum graveolens L. aerial parts by column chromatography using C6H6 : Ethanol (9:1) solvent as eluent. It was found that simultaneous administration of alkaloid compound A (500 mg/kg/day) and cholesterol for 4 weeks, significantly (P<0.01) prevented the rise in serum TC, TG, LDL-cholesterol, VLDL-cholesterol, atherogenic index and significantly (P<0.01) increased TAC and HDL-cholesterol as compared to cholesterol fed control rabbits. Thus, the results indicate antioxidant and hypolipidemic effect of alkaloid compound A of Anethum graveolens L. aerial parts
Eliminating a Region of Respiratory Syncytial Virus Attachment Protein Allows Induction of Protective Immunity without Vaccine-enhanced Lung Eosinophilia
In a murine model of respiratory syncytial virus disease, prior sensitization to the attachment glycoprotein (G) leads to pulmonary eosinophilia and enhanced illness. Three different approaches were taken to dissect the region of G responsible for enhanced disease and protection against challenge. First, mutant viruses, containing frameshifts that altered the COOH terminus of the G protein, were used to challenge mice sensitized by scarification with recombinant vaccinia virus (rVV) expressing wild-type G. Second, cDNA expressing these mutated G proteins were expressed by rVV and used to vaccinate mice before challenge with wild-type respiratory syncytial virus (RSV). These studies identified residues 193–205 to be responsible for G-induced weight loss and lung eosinophilia and showed that this region was not was not necessary for induction of protective immunity. Third, mice were sensitized using an rVV that expressed only amino acids 124–203 of the G protein. Upon RSV challenge, mice sensitized with this rVV developed enhanced weight loss and eosinophilia. This is the first time that a region within RSV (amino acids 193–203) has been shown to be responsible for induction of lung eosinophilia and disease enhancement. Moreover, we now show that it is possible to induce protective immunity with an altered G protein without inducing a pathological response
Influenza Virus Lung Infection Protects from Respiratory Syncytial Virus–Induced Immunopathology
The effect of infection history is ignored in most animal models of infectious disease. The attachment protein of respiratory syncytial virus (RSV) induces T helper cell type 2–driven pulmonary eosinophilia in mice similar to that seen in the failed infant vaccinations in the 1960s. We show that previous influenza virus infection of mice: (a) protects against weight loss, illness, and lung eosinophilia; (b) attenuates recruitment of inflammatory cells; and (c) reduces cytokine secretion caused by RSV attachment protein without affecting RSV clearance. This protective effect can be transferred via influenza-immune splenocytes to naive mice and is long lived. Previous immunity to lung infection clearly plays an important and underestimated role in subsequent vaccination and infection. The data have important implications for the timing of vaccinations in certain patient groups, and may contribute to variability in disease susceptibility observed in humans
Inhibition of T1/St2 during Respiratory Syncytial Virus Infection Prevents T Helper Cell Type 2 (Th2)- but Not Th1-Driven Immunopathology
T cells secreting interleukin (IL)-4 and IL-5 (T helper cell type 2 [Th2] cells) play a detrimental role in a variety of diseases, but specific methods of regulating their activity remain elusive. T1/ST2 is a surface ligand of the IL-1 receptor family, expressed on Th2- but not on interferon (IFN)-γ–producing Th1 cells. Prior exposure of BALB/c mice to the attachment (G) or fusion (F) protein of respiratory syncytial virus (RSV) increases illness severity during intranasal RSV challenge, due to Th2-driven lung eosinophilia and exuberant Th1-driven pulmonary infiltration, respectively. We used these polar models of viral illness to study the recruitment of T1/ST2 cells to the lung and to test the effects of anti-T1/ST2 treatment in vivo. T1/ST2 was present on a subset of CD4+ cells from mice with eosinophilic lung disease. Monoclonal anti-T1/ST2 treatment reduced lung inflammation and the severity of illness in mice with Th2 (but not Th1) immunopathology. These results show that inhibition of T1/ST2 has a specific effect on virally induced Th2 responses and suggests that therapy targeted at this receptor might be of value in treating Th2-driven illness