[Effect and mechanism of Jiming Powder on myocardial fibrosis in mice with myocardial infarction].

Jiming Powder is a traditional ancient prescription with good therapeutic effect in the treatment of heart failure, but its mechanism lacks further exploration. In this study, a mouse model of coronary artery ligation was used to evaluate the effect and mechanism of Jiming Powder on myocardial fibrosis in mice with myocardial infarction. The study constructed a mouse model of heart failure after myocardial infarction using the method of left anterior descending coronary artery ligation. The efficacy of Jiming Powder was evaluated from multiple angles, including ultrasound imaging, hematoxylin-eosin(HE) staining, Masson staining, Sirius Red staining, and serum myocardial enzyme spectrum detection. Western blot analysis was performed to detect key proteins involved in ventricular remodeling, including transforming growth factor-ß1(TGF-ß1), α-smooth muscle actin(α-SMA), wingless-type MMTV integration site family member 3a(Wnt3a), ß-catenin, matrix metallopeptidase 2(MMP2), matrix metallopeptidase 3(MMP3), TIMP metallopeptidase inhibitor 1(TIMP1), and TIMP metallopeptidase inhibitor 2(TIMP2). The results showed that compared with the model group, the high and low-dose Jiming Powder significantly reduced the left ventricular internal diameter in systole(LVID;s) and diastole(LVID;d), increased the left ventricular ejection fraction(LVEF) and left ventricular fractional shortening(LVFS), effectively improved cardiac function in mice after myocardial infarction, and effectively reduced the levels of myocardial injury markers such as creatine kinase(CK), creatine kinase isoenzyme(CK-MB), and lactic dehydrogenase(LDH), thus protecting ischemic myocardium. HE staining showed that Jiming Powder could attenuate myocardial inflammatory cell infiltration after myocardial infarction. Masson and Sirius Red staining demonstrated that Jiming Powder effectively inhibited myocardial fibrosis, reduced the collagen Ⅰ/Ⅲ ratio in myocardial tissues, and improved collagen remodeling after myocardial infarction. Western blot results showed that Jiming Powder reduced the expression of TGF-ß1, α-SMA, Wnt3a, and ß-catenin, decreased the levels of MMP2, MMP3, and TIMP2, and increased the level of TIMP1, suggesting its role in inhibiting cardiac fibroblast transformation, reducing extracellular matrix metabolism in myocardial cells, and lowering collagen Ⅰ and α-SMA content, thus exerting an anti-myocardial fibrosis effect after myocardial infarction. This study revealed the role of Jiming Powder in improving ventricular remodeling and treating myocardial infarction, laying the foundation for further research on the pharmacological effect of Jiming Powder.

Determination of n-octanol/water partition coefficients of weak ionizable solutes by RP-HPLC with neutral model compounds.

The utilization of neutral compounds as model compounds is put forward for determination of the n-octanol/water partition coefficient (K(ow)) of highly hydrophobic, weak acidic compounds by reversed-phase high performance liquid chromatography (RP-HPLC). It is based on a linear relationship between the logarithm of apparent n-octanol/water partition coefficient (log K(ow)″), expressing hydrophobicity of acidic solutes more accurately, and the logarithm of RP-HPLC retention factor of the solutes corresponding to the neat aqueous fraction of mobile phase (log k(w)). The availability of neutral model compounds was theoretically tested for this novel protocol. Moreover, a high consistency of linear log K(ow)″-log k(w) correlations was demonstrated between a mixed training set of neutral and acidic model compounds, and a training set of neutral model compounds. It is proved in theory that for a certain set of compounds investigated, all derived linear relationships between log K(ow)″ and log k(w) have a unit slope and the same intercept, regardless of mobile phase pH. This model was applied to measure log K(ow) of lipophilic aristolochic acid I (AA I) and aristolochic acid II (AA II). Log K(ow) values for AA I and AA II are 4.45±0.07 and 3.99±0.06, respectively. To the best of our knowledge, this is the first report on experimental log K(ow) data for AAs. The proposed strategy solves the problem of lacking suitable acidic model compounds with reliable experimental K(ow) in determining K(ow) of lipophilic acidic solutes by RP-HPLC.

Determination of n-octanol/water partition coefficient for DDT-related compounds by RP-HPLC with a novel dual-point retention time correction.

n-Octanol/water partition coefficients (P) for DDTs and dicofol were determined by reversed-phase high performance liquid chromatography (RP-HPLC) on a C(18) column using methanol-water mixture as mobile phase. A dual-point retention time correction (DP-RTC) was proposed to rectify chromatographic retention time (t(R)) shift resulted from stationary phase aging. Based on this correction, the relationship between logP and logk(w), the logarithm of the retention factor extrapolated to pure water, was investigated for a set of 12 benzene homologues and DDT-related compounds with reliable experimental P as model compounds. A linear regression logP=(1.10±0.04) logk(w) - (0.60±0.17) was established with correlation coefficient R(2) of 0.988, cross-validated correlation coefficient R(cv)(2) of 0.983 and standard deviation (SD) of 0.156. This model was further validated using four verification compounds, naphthalene, biphenyl, 2,2-bis(4-chlorophenyl)-1,1-dichloroethane (p,p'-DDD) and 2,2-bis(4-chlorophenyl)-1,1-dichloroethene (p,p'-DDE) with similar structure to DDT. The RP-HPLC-determined P values showed good consistency with shake-flask (SFM) or slow-stirring (SSM) results, especially for highly hydrophobic compounds with logP in the range of 4-7. Then, the P values for five DDT-related compounds, 2-(2-chlorophenyl)-2-(4-chlorophenyl)-1,1,1-trichloroethane (o,p'-DDT), 2-(2-chlorophenyl)-2-(4-chlorophenyl)-1,1-dichloroethane (o,p'-DDD), 2-(2-chlorophenyl)-2-(4-chlorophenyl)-1,1-dichloroethene (o,p'-DDE), and 2,2,2-trichloro-1,1-bis(4-chlorophenyl)ethanol (dicofol) and its main degradation product 4,4'-dichlorobenzophenone (p,p'-DBP) were evaluated by the improved RP-HPLC method for the first time. The excellent precision with SD less than 0.03 proved that the novel DP-RTC protocol can significantly increases the determination accuracy and reliability of P by RP-HPLC.