Abstract:Objective To explore the therapeutic effect and mechanism of the Danhe granules on hypercholesterolemia rats by observing the changes in the efficacy indicators and the levels of proteins related to the cholesterol metabolism pathway in the rats under the intervention of Danhe granules.Method SD rats were randomly assigned to either the blank group or the model group based on their body weight. The blank group had normal chow diets， while the model group was fed high-fat diets for seven weeks. One week after the establishment of the model， the content of the serum total cholesterol （TC） in the model rats was detected. According to the TC value， the model group was further randomly divided into a control group， pravastatin sodium tablet group（4.02 mg·kg-1）， Xuezhikang capsule group（0.12 g·kg-1）， high-dose， middle-dose， and low-dose groups of Danhe granules（4.536， 2.268， 1.134 g·kg-1）. After grouping the model groups， each treatment group received continuous oral gavage for six weeks， with weekly measurements of body weight and food intake （the difference between feed intake and feed surplus）. Six weeks later， the levels of serum TC， triglyceride （TG）， low-density lipoprotein cholesterol （LDL-C）， and high-density lipoprotein cholesterol （HDL-C） were measured. The liver pathology and lipid droplet distribution were evaluated by hematoxylin-eosin （HE） staining and oil red O staining， with scoring and calculation conducted. Rat liver tissue was collected， and western blot and immunohistochemistry （IHC） were used to detect the expression levels of cholesterol metabolism-related proteins namely phosphorylated adenosine 5'-monophosphate （AMP）-activated protein kinase （p-AMPK）， AMPK， 3-hydroxy-3-methyl glutaryl coenzyme A reductase （HMGCR）， low-density lipoprotein receptor （LDLR）， cholesterol 7α-hydroxylase （CYP7A1）， Acyl-coenzyme A： cholesterol acyltransferase 2 （ACAT2）， and apolipoprotein B （ApoB） in hypercholesterolemia rats.Result Compared with the blank group， the model group showed a significantly higher level of serum TC （P<0.01）. The TG level had no significant change， and the HDL-C level was significantly decreased （P<0.05）. The liver index， steatosis score， total score of pathological state， and the positive area ratio of oil red O staining were significantly increased （P<0.01）， and the protein expression levels of p-AMPK， p-AMPK/AMPK， LDLR， and CYP7A1 were significantly decreased （P<0.05， P<0.01）， while the protein expression levels of AMPK， HMGCR， and ACAT2 were significantly increased （P<0.05， P<0.01）. Compared with the model group， the TC level in each dose group of Danhe granules was significantly decreased （P<0.05）， and the positive area ratio of oil red O staining in the pravastatin sodium tablet group and medium-dose group of Danhe granules was significantly decreased （P<0.05）. In each administration group， the protein expression levels of p-AMPK and p-AMPK/AMPK were significantly increased （P<0.05， P<0.01）， and the levels of HMGCR and ACAT2 were significantly decreased （P<0.01）. The ApoB level showed a downward trend. The CYP7A1 level in the pravastatin sodium tablet group and each dose group of Danhe granules was significantly increased （P<0.05， P<0.01）， and the LDLR level in the pravastatin sodium tablet group， Xuezhikang capsule group， and high-dose and medium-dose groups of Danhe granules was significantly increased （P<0.05， P<0.01）.Conclusion Danhe granules can reduce serum TC levels and improve hepatic steatosis. It may activate AMPK， down-regulate the expression of HMGCR， and inhibit cholesterol synthesis. It can also up-regulate the expression of LDLR and CYP7A1， promote cholesterol uptake and excretion， down-regulate the expression of ACAT2 and ApoB， reduce cholesterol absorption and assembly of LDL and other lipoproteins， and thus play a role in the treatment of hypercholesterolemia.
