OBJECTIVETo observe the expression of protein arginine N-methyltransferase (PRMT) genes in the lung and spleen of E3 rats with acute asthma.

METHODSE3 rats with ovalbumin-induced pulmonary inflammation were divided into two groups (n=10), and the validity of the acute asthma model was evaluated by histological observation with HE and PAS staining and by measurement of NO production. Semi-quantitative RT-PCR was employed to detect the expressions of PRMT1-PRMT6 genes in the lung and spleen tissues of the rats.

RESULTSIn the lung tissue of the asthmatic rats, the gene expressions of PRMT1 (P<0.01), PRMT2 (P<0.01), PRMT3 (P<0.05) and PRMT5 (P<0.05) were significantly increased, but the expression of PRMT4 gene (P<0.05) was significantly decreased as compared with those in the control tissue. In the spleen tissue of the asthmatic rats, the expressions of PRMT2 (P<0.05) and PRMT5 genes (P<0.05) showed a significant increase as compared with those in the control rat tissue.

CONCLUSIONThe gene expressions of PRMTs vary significantly between asthmatic rats and control rats, suggesting that PRMTs play an important role in the post-translational modification process of asthma-related genes.

Acute Disease ; Animals ; Asthma ; enzymology ; Female ; Male ; Protein Processing, Post-Translational ; Protein-Arginine N-Methyltransferases ; classification ; genetics ; metabolism ; Random Allocation ; Rats ; Rats, Inbred Strains

The Chinese herbal medicine Tianma (Gastrodia elata) has been used for treating and preventing primary headache over thousands of years, but the exact pharmacological mechanism of the main bioactive ingredient gastrodin remains unclear. In present study, the effects of gastrodin on calcitonin gene-related peptide (CGRP) and phosphorylated extracellular signal-regulated kinase1/2 (pERK1/2) expression were observed in rat trigeminal ganglion (TG) after in vitro organ culture to explore the underlying intracellular mechanism of gastrodin on primary vascular-associated headache. CGRP-immunoreactivity (CGRP-ir) positive neurons count, positive area, mean optical density and integrated optical density by means of immunohistochemistry stain were compared at different concentrations of gastrodin, which was separately co-incubated with DMEM in SD rat TG for 24 hours. Only at 5 or 10 mmol L(-1) concentration, gastrodin demonstrated significantly concentration-dependent reduction of CGRP-ir (+) expression and its action closed to 1.2 mmol L(-1) sumatriptan succinate. While at 2.5, 20, and 40 mmol L(-1) concentration, gastrodin did not show remarkable effects on CGRP-ir (+) expression. The optimal concentration of gastrodin (5 and 10 mmol L(-1)) similarly inhibited CGRP-mRNA expression level separately compared with 1.2 mmol L(-1) sumatriptan succinate and 10 micromol L(-1) flunarizine hydrochloride, which was quantitatively analyzed by real-time PCR (RT-PCR). pERK1/2 level was examined by Western blotting after co-cultured with optimal concentration of gastrodin and effective specific ERK1/2 pathway inhibitors PD98059, U0126. The result indicated that gastrodin significantly reduced pERK1/2 protein actions similarly to ERK1/2 pathway specific blockade. It suggests ERK1/2 signaling transduction pathway may be involved in gastrodin intracellular mechanism. This study indicates gastrodin (5 and 10 mmol L(-1)) can remarkably reduce CGRP-ir (+) neuron, CGRP-mRNA and pERK1/2 expression level in cultured rat TG, with its actions similar to the effective concentration of sumatriptan succinate, flunarizine hydrochloride and specific ERK1/2 pathway blocker. The intracellular signaling transduction ERK1/2 pathway may be involved in the gastrodin reducing CGRP up-regulation in rat TG after organ culture.
Animals ; Benzyl Alcohols ; administration & dosage ; isolation & purification ; pharmacology ; Butadienes ; pharmacology ; Calcitonin Gene-Related Peptide ; genetics ; metabolism ; Dose-Response Relationship, Drug ; Flavonoids ; pharmacology ; Flunarizine ; pharmacology ; Gastrodia ; chemistry ; Glucosides ; administration & dosage ; isolation & purification ; pharmacology ; MAP Kinase Signaling System ; drug effects ; Male ; Mitogen-Activated Protein Kinase 1 ; antagonists & inhibitors ; metabolism ; Mitogen-Activated Protein Kinase 3 ; antagonists & inhibitors ; metabolism ; Nitriles ; pharmacology ; Organ Culture Techniques ; Plants, Medicinal ; chemistry ; RNA, Messenger ; Rats ; Rats, Sprague-Dawley ; Sumatriptan ; pharmacology ; Trigeminal Ganglion ; metabolism ; Vasoconstrictor Agents ; pharmacology ; Vasodilator Agents ; pharmacology