Progress of research on mechanism of salvia miltiorrhiza and its chemical ingredients against liver fibrosis

Optimization of Extraction Conditions for Maximal Phenolic, Flavonoid and Antioxidant Activity from Melaleuca bracteata Leaves Using the Response Surface Methodology

Melaleuca bracteata is a yellow-leaved tree belonging to the Melaleuca genus. Species from this genus are known to be good sources of natural antioxidants, for example, the “tea tree oil” derived from M. alternifolia is used in food processing to extend the shelf life of products. In order to determine whether M. bracteata contains novel natural antioxidants, the components of M. bracteata ethanol extracts were analyzed by gas chromatography–mass spectrometry. Total phenolic and flavonoid contents were extracted and the antioxidant activities of the extracts evaluated. Single-factor experiments, central composite rotatable design (CCRD) and response surface methodology (RSM) were used to optimize the extraction conditions for total phenolic content (TPC) and total flavonoid content (TFC). Ferric reducing power (FRP) and 1,1-Diphenyl-2-picrylhydrazyl radical (DPPH·) scavenging capacity were used as the evaluation indices of antioxidant activity. The results showed that the main components of M. bracteata ethanol extracts are methyl eugenol (86.86%) and trans-cinnamic acid methyl ester (6.41%). The single-factor experiments revealed that the ethanol concentration is the key factor determining the TPC, TFC, FRP and DPPH·scavenging capacity. RSM results indicated that the optimal condition of all four evaluation indices was achieved by extracting for 3.65 days at 53.26°C in 34.81% ethanol. Under these conditions, the TPC, TFC, FRP and DPPH·scavenging capacity reached values of 88.6 ± 1.3 mg GAE/g DW, 19.4 ± 0.2 mg RE/g DW, 2.37 ± 0.01 mM Fe²⁺/g DW and 86.0 ± 0.3%, respectively, which were higher than those of the positive control, methyl eugenol (FRP 0.97 ± 0.02 mM, DPPH·scavenging capacity 58.6 ± 0.7%) at comparable concentrations. Therefore, the extracts of M. bracteata leaves have higher antioxidant activity, which did not only attributed to the methyl eugenol. Further research could lead to the development of a potent new natural antioxidant.

A review of non-nucleoside anti-hepatitis B virus agents

Hepatitis B Virus is the most common cause of chronic liver disease worldwide. Currently approved agents of chronic HBV infection treatment include interferon and nucleoside analogues. However, the side effects of interferon and the viral resistance of nucleoside analogues make the current treatment far from satisfactory. Therefore, new drugs with novel structures and mechanisms are needed. Recently, a number of non-nucleoside HBV inhibitors have been obtained from natural sources or prepared by synthesis/semi-synthesis. Some of them exhibited potent anti-HBV activity with novel mechanisms. These compounds provide useful information for the medicinal chemist to develop novel non-nucleoside compounds as anti-HBV agents.

[Effects of Salviae miltiorrhizae and salvianolic acid B on microcirculation of liver in mice with portal hypertension]

OBJECTIVE

To observe the effects of Salviae miltiorrhizae and its component, salvianolic acid B (SA-B), on the microcirculation of liver in mice with portal hypertension induced by endothelin-1 (ET-1).

METHODS

Eighty-four Kunming mice were randomly divided into 7 groups: untreated group, endothelin A receptor (ETAR) blocker group, Astragali mongolici group, Astragalus polysaccharides (APS) group, Corydalis Yanhusuo group, Salviae miltiorrhizae group and SA-B group. There were 12 mice in each group. Mice were pretreated with a corresponding equivalent volume of drug or distilled water for 3 days, and then the portal hypertension in mice was induced by continuous injection of ET-1 into coccygeal vein using a micro-injection pump. Six mice in each group were used to observe the average liver blood flow volume by laser-Doppler flow instrument before and after injection of ET-1, and the other six rats were used to observe the hepatic microcirculation velocity in vivo by an inverted microscope.

RESULTS

The average blood flow of liver in mice decreased in each group after ET-1 injection. But the changes of average blood flow in the SA-B group and the ETAR blocker group were less than that in the untreated group (P<0.01). The changes of average blood volume in the Astragali mongolici group and the APS group were similar to that in the untreated group, but more than that in the SA-B group after injection of ET-1. The change of average blood flow in the SA-B group showed no significant difference when compared with the ETAR blocker group. The microcirculatory flow velocity in liver also decreased in each group after ET-1 injection. But the changes of microcirculatory flow velocity in the SA-B group and the ETAR blocker group were less than that in the untreated group (P<0.05, P<0.01). There were no significant differences in the changes of microcirculatory flow velocity among the Salviae miltiorrhizae group, the SA-B group and the ETAR blocker group.

CONCLUSION

Salviae miltiorrhizae and SA-B can decrease the average blood flow and microcirculatory flow velocity in liver in mice with portal hypertension, which may be one of the mechanisms of Salviae miltiorrhizae and SA-B in decreasing portal hypertension.

Investigation of the absorbed and metabolized components of Danshen from Fuzheng Huayu recipe and study on the anti-hepatic fibrosis effects of these components

ETHNOPHARMACOLOGY

Fuzheng Huayu recipe (FZHY) was formulated on the basis of Chinese medicine theory in treating liver fibrosis. It has a significant efficacy against liver fibrosis caused by chronic hepatitis B, with the action mechanisms of inhibition of hepatic stellate cell activation, protection of hepatocyte oxidative injury and regulations of hepatic matrix remodeling etc.

AIM OF THE STUDY

To identify the absorbed components and metabolites of Danshen in FZHY in rat serum, and find their active components for anti-liver fibrosis.

MATERIAL AND METHODS

A valid high performance liquid chromatography-electrospray ionization ion trap mass spectrometry (HPLC-ESI/MS(n)) method was established to investigate the absorbed and metabolized compounds of Danshen in FZHY in rat serum after oral administration. Mass spectra were acquired in both negative and positive modes. Otherwise, to evaluate the anti-hepatic fibrosis efficacies of absorbed and metabolized compounds, the LX-2 cell line of hepatic stellate cell (HSC), which was crucial cellular basis of fibrogenesis, was cultured and incubated with absorbed compounds, the cytotoxicity was determined with the cellomics Multiparameter Cytotoxicity Kit 1 by High Content Screening (HCS), the cell proliferation was assayed with EdU-DNA incorporation, and the cell activation was analyzed through α-smooth muscle actin (α-SMA) expression with high content screening technology.

RESULTS

More than 11 compounds and 2 metabolites from Danshen were identified in the serum after oral administration of FZHY by comparing their mass spectra and retention behavior with reference compounds or literature data. Among these compounds, there were no obvious changes in nuclear morphology, membrane permeability with blow 96 μM of six polar compounds treatment in comparison with control cells, respectively. And the salvianolic acid B (6 μM, 48 μM), caffeic acid (6 μM, 48 μM) and rosmarinic acid (48 μM) could obviously inhibit LX-2 cells proliferation, down-regulate α-SMA expression.

CONCLUSION

The results proved that the established method could be applied to analyze the absorbed into blood compounds of Danshen after oral administration FZHY. These absorbed compounds included 11 compounds and 2 metabolites of Danshen. Among them, the salvianolic acid B, caffeic acid and rosmarinic acid were the effective components of FZHY to anti-hepatic fibrosis effects.

An anti-ROS/hepatic fibrosis drug delivery system based on salvianolic acid B loaded mesoporous silica nanoparticles

The rhodamine B (RhB) covalently grafted SBA-15-structured mesoporous silica nanoparticles (MSNs-RhB) of high surface area (750 m(2) g(-1)), large pore volume (0.7 cm(3) g(-1)), uniform particle size (about 400 nm) and positively charged surface (29.6 +/- 5.0 mV), has been developed as a drug delivery system (SAB@MSNs-RhB) for anti-ROS (reactive oxygen species)/hepatic fibrosis by loading a negatively charged drug salvianolic acid B (SAB). The dosage formulation SAB@MSNs-RhB effectively protected the loaded drug SAB from decomposition. The multi-release experimental results showed that SAB@MSNs-RhB exhibited an outstanding SAB sustained-release property, and relatively high SAB release rates and concentrations in a long term after the consumption of previously released SAB as compared to SAB loaded MSNs (SAB@MSNs) of negatively charged surface (-31.1 +/- 2.6 mV). The influences of the drug concentration, incubation time, drug formula and drug carrier on the ROS level, proliferative activity and cytotoxicity of LX-2 cells were evaluated. The results showed that the inhibiting effect of SAB@MSNs-RhB on the ROS level and proliferative activity of LX-2 cells was more remarkable than free SAB in a long term (72 h), and became more intensive with the increase of the sample concentration and the incubation time. SAB@MSNs-RhB enhanced the cellular drug uptake, the drug bioaccessability and efficacy for anti-ROS/hepatic fibrosis via the nanoparticles-mediated endocytosis and the sustained release of the drug. There was no visible cytotoxicity of free SAB, MSNs-RhB and SAB@MSNs-RhB against LX-2 cells in a broad concentration range (0.5-100 microm) and incubation time periods up to 72 h. The blood compatibility of the carrier MSNs-RhB was evaluated by investigating the hemolysis and coagulation behaviors in a broad concentration range (50-500 microg mL(-1)) under in vitro conditions. The results suggested that MSNs-RhB possessed good blood compatibility.

Role of P-glycoprotein in restricting the brain penetration of tanshinone IIA, a major active constituent from the root ofSalvia miltiorrhizaBunge, across the blood–brain barrier

Tanshinone IIA (TSA) is a major constituent of Salvia miltiorrhiza Bunge widely used in the treatment of stroke. This current study aimed to investigate the nature of brain penetration of TSA using several in vitro and in vivo models. The uptake and efflux of TSA in primary rat brain microvascular endothelial cells (RBMVECs) were altered in the presence of a PgP inhibitor or multidrug-resistance-associated protein (Mrp1/2) inhibitor. A polarized transport of TSA was found in RBMVEC monolayers with facilitated efflux from the abluminal to the luminal side. The polarized transport of TSA was attenuated by PgP or Mrp1/2 inhibitors. In an in situ rat brain perfusion model, TSA crossed the blood-brain barrier at a greater rate than that for sucrose, and the brain penetration was increased in the presence of a PgP or Mrp1/2 inhibitor. The brain levels of TSA were only about 31% of that in the plasma and it increased to 74-77% of plasma levels when verapamil or quinidine was coadministered in rats. The entry of TSA to the central nervous system (CNS) significantly increased in rats subjected to middle cerebral artery occlusion or treatment with quinolinic acid. The normalized brain penetration of TSA in mdr1a((-/-)) mice was much higher than the wild-type mice. Taken collectively, these findings provide evidence that TSA has limited brain penetration through the blood-brain barrier owing to the contribution of PgP and possibly Mrp1/2.

Preclinical factors affecting the pharmacokinetic behaviour of tanshinone IIA, an investigational new drug isolated from Salvia miltiorrhiza for the treatment of ischaemic heart diseases

Tanshinone IIA (TSIIA) is a major active triterpenoid isolated from Salvia miltiorrhiza. The purposes of this study were to investigate various preclinical factors that determined the pharmacokinetics of TSIIA. After oral dosing at 6.7, 20, and 60 mg kg(-1), TSIIA was detected mainly as glucuronidated conjugate (TSIIAG) with only small amounts of the unchanged in the plasma. TSIIA was predominantly excreted into the bile and faeces as TSIIAG, and urine to a minor extent. The C(max) and AUC(0-)(t) of TSIIAG after i.p. administration were significantly lower than those after intragastric administration. The plasma concentration-time profiles of TSIIA following oral dosing of TSIIA showed multiple peaks. The C(max) and AUC(0-)(t) of TSIIA and its glucuronides in rats with intact bile duct were significantly lower than those of rats with bile duct cannulation. Studies from the linked-rat model and intraduodenal injection of bile containing TSIIA and its metabolites indicate that TSIIA glucuronides underwent hydrolysis and the aglycone was reabsorbed from the gut and excreted into the bile as conjugates. TSIIA had a wide tissue distribution, with a very high accumulation in the lung, but very limited penetration into the brain and testes. TSIIA was metabolized by rat CYP2C, 3A and 2D, as ticlopidine, ketoconazole and quinidine all inhibited TSIIA metabolism in rat liver microsomes. Taken collectively, these findings indicate that multiple factors play important roles in determining the pharmacokinetics of TSIIA.

Traditional Chinese herbal medicines for treatment of liver fibrosis and cancer: from laboratory discovery to clinical evaluation

Liver disease afflicts over 10% of the world population. This includes chronic hepatitis, alcoholic steatosis, fibrosis, cirrhosis and hepatocellular carcinoma (HCC), which are the most health-threatening conditions drawing considerable attention from medical professionals and scientists. Patients with alcoholism or viral hepatitis are much more likely to have liver cell damage and cirrhosis, and some may eventually develop HCC, which is unfortunately, and very often, a fatal malignancy without cure. While liver surgery is not suitable in many of the HCC cases, patients are mostly given palliative support cares or transarterial chemoembolization or systemic chemotherapies. However, HCC is well known to be a highly chemoresistant tumour, and the response rate is <10-20%. To this end, alternative medicines are being actively sought from other sources with hopes to halt the disease's progression or even eliminate the tumours. Traditional Chinese herbal medicine has begun to gain popularity worldwide for promoting healthcare as well as disease prevention, and been used as conventional or complementary medicines for both treatable and incurable diseases in Asia and the West. In this article, we discuss the laboratory findings and clinical trial studies of Chinese herbal medicines (particularly small molecule compounds) for the treatment of liver disease ranging from fibrosis to liver cancer.

[Effects of salvianolic acid B on expressions of TGF-beta1 and its receptors in liver of rats with dimethylnitrosamine-induced hepatic fibrosis]

OBJECTIVE

To study the therapeutic mechanism of salvianolic acid B (SA-B) in treating hepatic fibrosis.

METHODS

Twenty-four Wistar rats were randomly divided into 3 groups: normal control group, untreated group and SA-B-treated group. Rats in the untreated and SA-B-treated groups were injected intraperitoneally with 0.5% dimethylnitrosamine (DMN) for 4 weeks, daily for 3 days each week at a dose of 10 microg/kg, to induce hepatic fibrosis. Then, rats in the SA-B-treated group were given SA-B orally for another 4 weeks. Hydroxyproline (Hyp) contents in liver tissue of the rats in 3 groups were determined with HCl hydrolysis, and collagen type I, transforming growth factor-beta 1 (TGF-beta1), transforming growth factor-beta receptor type I (TbetaRI) and transforming growth factor-beta receptor type II (TbetaRII) were detected by Western blotting.

RESULTS

The Hyp content and the expressions of collagen type I, TGF-beta1, TbetaRI and TbetaRII in the liver tissue of rats in the untreated group increased significantly as compared with those in the normal control group, while those in SA-B-treated group decreased significantly as compared with those in the untreated group.

CONCLUSION

The therapeutic mechanism of SA-B in treating hepatic fibrosis may be related to inhibiting the expressions of TGF-beta1 and its receptors.

[Expression of TIMP-1 and TGF-beta1 mRNA in hepatic fibrosis rats and the therapeutic effects of Bushen Rougan Recipe]

OBJECTIVE

To study the expression of TIMP-1 and TGF-beta1 mRNA in hepatic fibrosis rats and the therapeutic effects of Bushen Rougan Recipe (BSRGR).

METHODS

Hepatic fibrosis was induced in rats by dimethylnitrosamine (DMN). The rats' hepatic tissue was studied by HE staining and Sirius red staining. The rats were divided into normal control group, fibrosis model group and BSRGR treated group (10 g.kg(-1).d(-1), i.g. for 4 weeks). At last, TIMP-1 and TGF-beta1 mRNA were detected by RT-PCR.

RESULTS

Pathological study showed that hepatic fibrosis was successfully induced by DMN in rats. The expression quantity of TIMP-1 and TGF-beta1 mRNA were the most in the fibrosis model group, the second in the BSRGR treated group, and the least in the normal control group.

CONCLUSION

The expression of TIMP-1 and TGF-beta1 mRNA was increased in the hepatic fibrosis rats, and this is one possible mechanism of hepatic fibrosis. BSRGR can inhibit the advancement of hepatic fibrosis.