ABSTRACT
Objectives To observe the effect of low intensity pulsed ultrasound (LIPUS) on osteocyte injuries induced by the tricalcium phosphate(TCP) wear particles in the calvaria of mice.Methods Thirty ICR male mice of 6 to 8 weeks were randomly divided into a normal control group(n=10),a model group (n=10) and a LIPUS-treated group(n=10).A murine calvarial model of osteolysis was established in the model and LIPUS-treated groups through injecting TCP particles onto the surface of bilateral parietal bones at week 1,3,5,7 and 11.Mice in the normal group received negative ultrasound probe pressing,while those in the LIPUS-treated received LIPUS radiation.Three months later,the calvarias were obtained.The micro-CT,HE staining,flow cytometry and Western blotting were performed to estimate the calvarial osteolysis,osteocyte death,apoptosis and proteins expression of the dentin matrix protein 1 (DMP-1),sclerosis protein (SOST),glucose-regulated protein78 (GRP78),inositol-requiring enzyme(IRE 1 α),spliced X-box binding protein 1 (XBP1 s),c-Jun N-terminal kinase (JNK) and phosphorylated c-Jun N-terminal kinase(p-JNK) respectively.Results Compared with the normal control group,in the model group the viability of prosthetic osteocytes decreased significantly,and cell apoptosis was more obvious(P＜0.05);the osteocytic marker protein DMP-1 down-regulated significantly,but another marker protein SOST up-regulated significantly,which caused the decline in DMP-1/SOST(P＜0.05).Moreover,the expression levels of GRP78,IRE1,XBPls and p-JNK of the model group increased significantly(P＜0.05) in the calvaria osteocytes compared to the control group.However,in the LIPUS treatment group,osteocyte injuries and endoplasmic reticulum(ER) stress both decreased significantly,shown by a significant increase in the number and activity of osteocytes,DMP-1/SOST,and significant inhibition of the IRE1α-XBP1-JNK activation(P＜0.05).Conclusion LIPUS prevents osteocyte injuries induced by TCP wear particles in the calvaria of mice,which may be due to the inhibition of IRE1α-XBP1-JNK pathway activation through ER stress reaction.
ABSTRACT
Objective To observe the effect of 7 kinds of Chinese herbs(Pericarpium Arecae, Folium Sennae, Fructus Tsaoko, Fructus Amomi, Rhizoma Atractylodis Macrocephalae, Fructus Aurantii, Fructus Aurantii I mmaturus), and 2 kinds of active compounds (bornyl acetate, synephrine) of Chinese herbals on gastrointestinal motility of chronic experimental beagle model. Methods Six beagles were used for inducing chronic experimental model. The beagles’antrum, duodenum, jejunum, ileum and colon were implanted with strain gauges to record canine gastrointestinal motility. Gastric fistula was set up for the intake of Chinese medicine decoction, and the external jugular vein catheter was made for intravenous administration. After modeling, the fasting gastrointestinal motility features of the beagles were observed for 120 min every day, and for 7 continuous days. From the 7th day after modeling, fasting gastrointestinal motility before medication was recorded as fundamental control, and when the interdigestive migrating motor complex (MMC) I phase arrived, the gastrointestinal motilities were sequently recorded after treatment with the 7 kinds of herbs(gavage of 200 mL of the decoction of each herb through gastric fistula), normal saline(200 mL), bornyl acetate(active ingredient of Fructus Aurantii and Fructus Aurantii Immaturus, intravenous injection), and synephrine (active ingredient of Fructus Amomi, intravenous injection). All of the animals were treated with only one kind of Chinese herb one day , and the observation of each herb lasted for 2 continuous days. MMC cycle, frequency of contraction, sum of contraction, amplitude of contraction, average of amplitude, and motor index (MI) were observed by strain gauges. Results On postoperative day 1-6, the animals had gastrointestinal hypomotility and no MMC cycle was recorded. On postoperative day 7, the canine antrum, duodenum, jejunum and ileum showed typical MMC cycle while the colon had irregular MMC cycle at fasting interdigestive period. Compared with the gastrointestinal motilities before treatment and those of the normal saline group, the number of contraction waves and MI were significantly increased in the antrum, duodenum, jejunum, ileum and colon after intervention with Pericarpium Arecae and bornyl acetate, were increased in the duodenum, jejunum, ileum and colon after treatment with Folium Sennae and Fructus Tsaoko (P<0.05), and were also enhanced in the antrum and duodenum after administration of Fructus Amomi(P < 0.05). Treatment with Fructus Aurantii induced the decrease of MI in the jejunum, Fructus Aurantii Immaturus decreased MI of the jejunum and colon, and synephrine decreased the number of antrum contraction waves and MI of the antrum and jejunum(P < 0.05). Conclusion The chronic experimental model is effective for the screening of Chinese herbs for improving gastrointestinal motility. Pericarpium Arecae, Folium Sennae, Fructus Tsaoko, Fructus Amomi, and bornyl acetate can increase gastrointestinal motility, while Fructus Aurantii, Fructus Aurantii Immaturus and synephrine can inhibit the gastrointestinal movement, and Rhizoma Atractylodis Macrocephalae has no effect on gastrointestinal motility.