[Effect and mechanism of Linggui Zhugan Decoction in regulating Sig1R on AngⅡ-induced cardiomyocyte hypertrophy]

This study aims to explore the mechanism of Linggui Zhugan Decoction(LGZGD) in inhibiting Angiotensin Ⅱ(AngⅡ)-induced cardiomyocyte hypertrophy by regulating sigma-1 receptor(Sig1R). The model of H9c2 cardiomyocyte hypertrophy induced by AngⅡ in vitro was established by preparing LGZGD-containing serum and blank serum. H9c2 cells were divided into normal group, AngⅡ model group, 20% normal rat serum group(20% NSC), and 20% LGZGD-containing serum group. After the cells were incubated with AngⅡ(1 μmol·L~(-1)) or AngⅡ with serum for 72 h, the surface area of cardiomyocytes was detected by phalloidine staining, and the activities of Na~+-K~+-ATPase and Ca~(2+)-Mg~(2+)-ATPase were detected by micromethod. The mitochondrial Ca~(2+) levels were detected by flow cytometry, and the expression levels of atrial natriuretic peptide(ANP), brain natriuretic peptide(BNP), Sig1R, and inositol 1,4,5-triphosphate receptor type 2(IP_3R_2) were detected by Western blot. The expression of Sig1R was down-regulated by transfecting specific siRNA for investigating the efficacy of LGZGD-containing serum on cardiomyocyte surface area, Na~+-K~+-ATPase activity, Ca~(2+)-Mg~(2+)-ATPase activity, mitochondrial Ca~(2+), as well as ANP, BNP, and IP_3R_2 protein expressions. The results showed that compared with the normal group, AngⅡ could significantly increase the surface area of cardiomyocytes and the expression of ANP and BNP(P<0.01), and it could decrease the activities of Na~+-K~+-ATPase and Ca~(2+)-Mg~(2+)-ATPase, the concentration of mitochondrial Ca~(2+), and the expression of Sig1R(P<0.01). In addition, IP_3R_2 protein expression was significantly increased(P<0.01). LGZGD-containing serum could significantly decrease the surface area of cardiomyocytes and the expression of ANP and BNP(P<0.05, P<0.01), and it could increase the activities of Na~+-K~+-ATPase and Ca~(2+)-Mg~(2+)-ATPase, the concentration of mitochondrial Ca~(2+ )(P<0.01), and the expression of Sig1R(P<0.05). In addition, IP_3R_2 protein expression was significantly decreased(P<0.05). However, after Sig1R was down-regulated, the effects of LGZGD-containing serum were reversed(P<0.01). These results indicated that the LGZGD-containing serum could inhibit cardiomyocyte hypertrophy induced by AngⅡ, and its pharmacological effect was related to regulating Sig1R, promoting mitochondrial Ca~(2+ )inflow, restoring ATP synthesis, and protecting mitochondrial function.

[Study on preparation extraction process of Linggui Zhugan Decoction]

To verify the appropriate preparation process of extracts for the solid substance benchmark of Linggui Zhugan Decoction. The extracts were prepared by different preparation processes, namely the traditional process(process 1), the extract combined with volatile oil separated from traditional process extract liquid(process 2), the modern secondary reflux extraction process(process 3) and the process that volatile oil was extracted first, then prepared according to the traditional process, and combined with extract(process 4); based on the characteristic spectrum, index components of cinnamaldehyde, glycyrrhizin, ammonium glycyrrhizinate, cinnamic acid, and the dry extract rate of process 1, the differences and similarities of four extracts were compared. The results showed that the similarity of the characteristic spectrum of process 2, process 4 and process 1 were all greater than 0.97, while there was no significant difference for the content of 4 quality control components and dry extract rate; the similarity of the characteristic spectrum of process 3 and process 1 was 0.91, the absolute peak area of 13 out of 21 peaks and the relative peak area of 7 peaks increased significantly, and the content of 3 out of 4 quality control components and dry extract rate also significantly increased. In conclusion, the material standards of extracts by the process 2 and 4 are consistent with that of the traditional process, so the two processes are suitable.

[Analysis on quality value transmitting of substance benchmarks of Linggui Zhugan Decoction]

By preparing 10 batches of the material reference of Linggui Zhugan Decoction,the methodology of the characteristic spectrum of the material reference was created. The creaming rate range,the contents and the transfer rate range of cinnamaldehyde,glycyrrhizin and glycyrrhizic acid,the characteristic peaks and the similarity range of the characteristic spectrum of Linggui Zhugan Decoction were determined to clarify key quality attributes of the material reference of Linggui Zhugan Decoction. In the 10 batches of the material reference of Linggui Zhugan Decoction,the similarity of characteristic spectrum was higher than 0. 9. Furthermore,after summarizing the characteristic peak information,we knew that Fuling had two characteristic peaks,Guizhi had six characteristic peaks,Baizhu had two characteristic peaks and Gancao had 11 characteristic peaks. The average creaming rate of the material reference of the ten batches was( 12. 13 ± 0. 35) %. The average content of cinnamaldehyde was 0. 32%,the average transfer rate was 10. 69%,the content of cinnamaldehyde in the different batches was between 0. 22% and 0. 42%,and the transfer rate was between 7. 48% and13. 90%. The average content of glycyrrhizin was 0. 84%,the average transfer rate was 50. 39%,the content of glycyrrhizin in the different batches was between 0. 42% and 1. 26%,and the transfer rate was between 35. 27% and 65. 51%. The average content of glycyrrhizic was 1. 88%,the average transfer rate was 40. 74%,the content of glycyrrhizic in the different batches was between 0. 94% and2. 82%,and the transfer rate was between 28. 52% and 52. 96%. In this paper,the quality value transmitting of substance benchmarks of Linggui Zhugan Decoction was analyzed by the combination of characteristic spectrum,creaming rate and the content of index component. A scientific and stable method was preliminarily established,which provided scientific basis for the quality control and formulation development of Linggui Zhugan Decoction.