6448
In this study , we investigated the direct protective mechanisms of tigecycline against lipopolysaccharide ( LPS ) - induced Rat pheochromocytoma ( PC12 ) cells .
 Chemical: tigecycline
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
 Chemical: tigecycline