Effects of Two Chinese Herbs on Muscle Composition after 14 d of Hind-limb Unloading in Rats

QIN Wen; GAO Yun-fang; XUE Wei; ZHANG Hai-xiang; WANG Hui-ping; Helmut Hinghofer-Szalkay

Abstract：Objective To study the effects of two Traditional Chinese Herbs (Angelica sinensis and Ligusticum)as a countermeasure on muscle atrophy and myosin Ⅱ heavy chain (MHC Ⅱ) expression in soleus fibers of arat model (tail-suspended) hind-limb unloaded. Methods Six rats each were assigned to a 4-group design: con-trol group (Con), other 3 groups respectively to be hind-limb unloading plus intragastric instillation of water (HLU + W), of Angelica sinensis decoction (HLU + Ang) and of Ligusticum decoction (HLU + Lig). The myosin Ⅱ heavy chain (MHC Ⅱ) expression in soleus fibers were measured with immuno-histo-chemical meth-od. Results As all 3 hind-limb unloading groups (HLU + W, HLU + Ang and HLU + Lig) compared to Con,in soleus muscle wet weight (MWW), muscle wet weight to body weight ratio (MWW/BW) and type Ⅰ and Ⅱ fiber CSA decreased, whereas MHC Ⅱ expression and the percentage of type Ⅱ fibers increased. Compared to untreated group(HLU + W), Angelica sinensis enhanced type Ⅰ and Ⅱ fiber CSA by 29% and 35% respective-ly, expression of MHC Ⅱ (type Ⅱ fiber percentage) decreased as well as Ligusticum increased type Ⅰ fiber CSA by 25% (P = 0. 064) and reduced M HC Ⅱ expression (decreased type Ⅱ fiber percentage). Conclusion Both Angelica sinensis and Ligusticum can alleviate the weightlessness-induced shift from slow-twitch to fast-twitch fibers. Angelica sinensis also can alleviate CSA reduction of soleus muscle in hind-limb unloaded rats.