Ligusticum chuanxiong Hort: a review of chemistry and pharmacology

CONTEXT

Ligusticum chuanxiong Hort (LC; Umbelliferae) is an effective medical plant, which has been extensively applied for many years to treat various diseases with other Chinese herbal medicines. Although a considerable amount of scientific research was reported on LC in the last decade, it is currently scattered across various publications. The present review comprises the chemical and pharmacological research on LC in the last decade.

OBJECTIVE

The objective of this review is to bring together most of the scientific research available on LC and evaluate its effects and mechanisms.

METHODS

The information for 82 cases included in this review was compiled using major databases such as Medline, Elsevier, Springer, Pubmed, and Scholar.

RESULTS

The compounds contained in LC can be divided into five kinds, essential oil (EO), alkaloids, phenolic acids, phthalide lactones, and other constituents. A great deal of pharmacological research has been done, which mainly focuses on cardiovascular and cerebrovascular effects, antioxidation, neuroprotection, antifibrosis, antinociception, antiinflammation, and antineoplastic activity.

CONCLUSION

A large number of pharmacological and chemical studies during the last 10 years have demonstrated the vast medicinal potential of LC. It is still very clear that LC is a plant with widespread use now and also with extraordinary potential for the future. The documents strongly support the view that LC has beneficial therapeutic properties and indicates its potential as an effective adaptogenic herbal remedy.

Relaxation effects of ligustilide and senkyunolide A, two main constituents of Ligusticum chuanxiong, in rat isolated aorta

Ligusticum chuanxiong Hort. (Umbelliferae) is a widely prescribed traditional Chinese medicinal herb for cardiovascular diseases in China. However, the cardiovascular actions of ligustilide and senkyunolide A, two of the most abundant Ligusticum chuanxiong constituents, have yet to be examined. The objective of the present study was to investigate the vasorelaxation effects of ligustilide and senkyunolide A and their underlying mechanisms in rat isolated aorta. Both constituents had similar relaxation potencies against contractions to 9,11-dideoxy-9alpha,11alpha-methanoepoxyprostaglandin F(2alpha), phenylephrine, 5-hydroxytryptamine and KCl. Their vasorelaxation effects were not affected by endothelium removal, the adenylate cyclase inhibitor 9-(tetrahydro-2-furanyl)-9H-purin-6-amine, the soluble guanylate cyclase inhibitor 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one, or the non-selective K+ channel blocker tetraethylammonium. This is the first report to demonstrate the vasorelaxation activities of ligustilide and senkyunolide A in contractions to various contractile agents in rat isolated aorta. The underlying mechanisms await further investigations.

Protective effect of Ligusticum chuanxiong and Angelica sinensis on endothelial cell damage induced by hydrogen peroxide

Ligusticum chuanxiong and Angelica sinensis have been widely used in traditional Chinese medicine to treat some pathological settings such as atherosclerosis and hypertension. We determined the protective effect of the extract of Ligusticum chuanxiong and Angelica sinensis (ELCAS) on human umbilical vein endothelial cells (ECV304) damage induced by hydrogen peroxide. ECV304 cells were pre-treated with ELCAS and exposed to 5 mM hydrogen peroxide. The results show that ELCAS dose- and time-dependently protected ECV304 cells against hydrogen peroxide damage and suppressed the production of reactive oxygen species (ROS). The decrement of ROS may be associated with increased activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX). Western blot analysis revealed that ELCAS significantly increased the phosphorylation of ERK and promoted eNOS expression. These observations indicate that ELCAS protected ECV304 cells against hydrogen peroxide damage by enhancing the antioxidative ability, activating ERK and eNOS signaling pathway. Our data also provide new evidence of Ligusticum chuanxiong and Angelica sinensis in preventing both cardiovascular and cerebrovascular diseases.

Simultaneous analysis of seventeen chemical ingredients of Ligusticum chuanxiong by on-line high performance liquid chromatography-diode array detector-mass spectrometry

An on-line high performance liquid chromatography (HPLC)-diode array detector (DAD)-mass spectrometry (MS) analytical method has been developed to simultaneously separate and identify seventeen main constituents of Chuanxiong ( Ligusticum chuanxiong Hort.), a traditional Chinese medicinal herb. In three Chuanxiong samples, nine compounds were unequivocally determined as vanillin (1), ferulic acid (2), senkyunolide I (4), senkyunolide H (5), senkyunolide A (6), coniferyl ferulate (7), Z-ligustilide (8), neocnidilide (9) and 3-butylidenephthalide (10) by comparing their t R, UV, and MS data with those obtained for the authentic compounds. Furthermore, additional eight compounds were tentatively identified as senkyunolide J (11), senkyunolide F (12), 3-butylphthalide (13), cnidilide (14), riligustilide (15) or Z,Z'-6,8',7,3'-diligustilide (16), tokinolide B (17), levistolide A (18) and senkyunolide P (19), based on their MS data and the comparison of their UV spectra with the published references. This is the first report to describe the development of an on-line HPLC-DAD-MS method to simultaneously analyse seventeen main constituents present in Chuanxiong and to construct the chemical profiles of various Chuanxiong samples.

Simultaneous quantification of 12 bioactive components of Ligusticum chuanxiong Hort. by high-performance liquid chromatography

A sensitive and specific HPLC-UV method has been developed, for the first time, to simultaneously quantify 12 bioactive ingredients in Ligusticum chuanxiong Hort. (Rhizoma Chuanxiong). This assay was fully validated in respect to precision, accuracy and sensitivity. This method was successfully applied to quantify twelve ingredients in six different Chuanxiong samples. The results demonstrated significant variations in the total content and quantity of each of the main bioactive compounds in different herbs, indicating that quality control of bioactive ingredients in Chuanxiong is critical to ensure its clinical benefits. This assay can be readily utilized as quality control method for Chuanxiong.

Tetramethylpyrazine protects rat renal tubular cell apoptosis induced by gentamicin

BACKGROUND

Gentamicin, a widely used antibiotic for the treatment of bacterial infection, can cause nephrotoxicity. Tetramethylpyrazine (TMP) is a compound purified from the rhizome of Ligusticum wallichi (Chuanxiong) and has been found to protect against ischaemia-reperfusion injury, nephritis and alcohol-induced toxicity in rat kidneys.

METHODS

We used rat renal tubular cells (RTCs), NRK-52E, in this study. The cytotoxicity of gentamicin was checked with transferase-mediated deoxyuridine triphosphate nick end-labeling (TUNEL) staining, and the generation of reactive oxygen species was measured using the fluorescent probe 2,7-dichlorofluorescein. We evaluated several apoptotic parameters: cleaved caspase levels, tumour necrosis factor (TNF-alpha) excretion and nuclear factor Kappa B (NF-kappaB) activity. We also examined the TMP protective effect on gentamicin-induced apoptosis in rat kidneys.

RESULTS

The results of this study showed that gentamicin was found to markedly induce apoptosis in NRK-52E cells in a dose-dependent manner; that TMP expressed a dose-dependent protective effect against gentamicin-induced apoptosis; that pre-treatment of the cells with 50 or 100 microM of TMP effectively decreased the reactive oxygen species formation induced by gentamicin; that TMP was found to inactivate the gentamicin-stimulated activities of caspase-3, caspase-8 and caspase-9, to inhibit gentamicin-induced release of cytochrome c, as well as to raise the expression of Bcl-x(L); that TMP inhibited the gentamicin-induced TNF-alpha excretion, and inactivated the transcription factor NF-kappaB; and that the TMP treatment significantly reduced apoptotic injury in rat RTCs.

CONCLUSIONS

Based on the results of this study, we suggest that TMP can attenuate gentamicin-induced oxidative stress and apoptotic injury in rat RTCs, and that its character may have therapeutic potential for patients with renal diseases.

Mechanisms underlying the vasorelaxing effects of butylidenephthalide, an active constituent of Ligusticum chuanxiong, in rat isolated aorta

Butylidenephthalide (BDPH) is one of the most potent vasorelaxants isolated from Ligusticum chuanxiong Hort. The objective of the current study is to investigate the underlying vasorelaxation mechanisms in rat aorta. In 9,11-dideoxy-9alpha,11alpha-methanoepoxyprostaglandin F(2alpha) (U46619) precontracted preparations, endothelium removal, the nitric oxide (NO) synthase inhibitor Nomega-nitro-l-arginine methyl ester (l-NAME) and the soluble guanylate cyclase inhibitor 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ) partially inhibited the BDPH relaxation response to a similar extent. The cyclooxygenase inhibitor indomethacin, beta-adrenoceptor antagonist propranolol, adenylate cyclase inhibitors 9-(tetrahydro-2-furanyl)-9H-purin-6-amine (SQ 22536) and 2',5'-dideoxyadenosine, and K(+) channel blocker tetraethylammonium had no effect. BDPH produced full relaxation against contractions induced by KCl and U46619 in the presence of the l-type voltage-operated Ca(2+) channel (Ca(v) 1.2) blocker nifedipine. In a receptor-operated Ca(2+) channel protocol where contraction was mediated by Ca(2+) re-addition in the presence of U46619 and nifedipine, BDPH produced relaxation. In the absence of extracellular Ca(2+), BDPH inhibited contractions induced by phorbol-12,13-dibutyrate and U46619. Our results suggest that BDPH-mediated vasorelaxation comprises both endothelium-dependent (NO) and independent components. It is suggested that BDPH acting through an inhibitory mechanism downstream to l-type voltage-operated and prostanoid TP receptor-operated Ca(2+) channels operating late in the contractile pathway.

New approach on similarity analysis of chromatographic fingerprint of herbal medicine

A new approach to the construction and similarity analysis of chromatographic fingerprint for herbal medicine is presented in this paper. Samples of chuanxiong, a herbal medicine for headache, from three producing areas of China were used to evaluate the utility of this study. The samples were analyzed with high-performance liquid chromatography (HPLC) and the peak areas of the chromatograms were used to construct the fingerprints of the herbal medicines. A vector of differences was defined between the two fingerprints. The scalar mean of the difference vector was taken as a statistic and both the t-test and Bayesian hypothesis testing were implemented to provide a one-to-one comparison of the fingerprints. Compared with principal component analysis (PCA), correlation coefficient and vector cosine, the new method offers a better differentiation of the similarity or difference between the fingerprints from same sample of chuanxiong. When the new method was used in the similarity analysis of the fingerprints of chuanxiong from different production areas, a clear-cut signature was obtained that reveals the significant difference between them.

Ligustrazine improves atherosclerosis in rat via attenuation of oxidative stress

CONTEXT

Ligustrazine (Lig) is a compound isolated from the rhizome of Ligusticum chuanxiong Hort. (Umbelliferae) and has been reported to be effective for the treatment of a variety of vascular diseases.

OBJECTIVE

The anti-atherosclerotic activities of Lig are evaluated in vivo for the first time in the present study.

MATERIALS AND METHODS

We gave rats a single injection of vitamin D3 and then fed them with an atherogenic diet for 6 weeks to induce atherosclerosis. Lig was simultaneously given to rats by gavage at the dose of 20 or 80 mg/kg in the therapy groups. Multiple approaches including spectrophotometry, hematoxylin and eosin (H&E) staining, and quantitative RT-PCR were applied to investigate the effects of Lig on blood parameters, aorta and liver histology, and gene expression. In addition, the solely effects of Lig on food intake, body weight gain, and taste preference were also evaluated.

RESULTS

We found that two doses of Lig treatment decreased the total cholesterol levels by 65.2 and 76.7%, respectively, in the plasma. Triglyceride (by 53.2 and 77.9%) and low-density lipoprotein (by 71.2 and 79.0%) levels were also decreased. However, high-density lipoprotein level was slightly increased. The circulating endothelial cells were decreased by 42.2 and 60.0% in Lig-treated rats, indicating the attenuation of endothelial injury. In contrast, Lig restored the total antioxidant capacity and superoxide dismutase 1 (SOD1) activity while decreasing the MDA generation. Furthermore, Lig improved liver dysfunction by decreasing ALT (by 13.0 and 49.7%) and AST (by 10.7 and 14.3%) levels. Histological examinations revealed that Lig suppressed atherosclerotic plaque progression in the thoracic aorta and lipid accumulation in the liver. At the transcriptional level, Lig inhibited the induction of antioxidant genes both in aorta and in liver. Lig also suppressed the mRNA expression of the genes involved in the hepatic fatty acid oxidation. Finally, Lig had a minimum effect on food intake, body weight gain, and taste preference.

DISCUSSION AND CONCLUSION

Our results suggest that Lig suppresses the development of atherosclerosis and hepatic lipid accumulation via the alleviation of oxidative stress and the improvement of dyslipidemia.

Specific inhibiting characteristics of tetramethylpyrazine, one of the active ingredients of the Chinese herbal medicine 'Chuanxiong,' on platelet thrombus formation under high shear rates

We have investigated the effects of tetramethylpyrazine, one of the active ingredients of the Chinese herbal medicine Chuanxiong, on platelet thrombus formation under flow conditions. We demonstrate herein that tetramethylpyrazine inhibits shear-induced platelet aggregation under relatively high shear rate of 10,800 s(-1) with modest inhibition of those occurring under relatively low shear rate of 1200 s(-1) by using optically modified cone-plate viscometer. We also demonstrate that platelet activation induced by shearing in the absence of exogenous platelet-activating agents such as ADP as evidenced by P-selectin surface expression and microparticle release detected by quantitative flow cytometry was also inhibited by tetramethylpyrazine. Moreover, we also demonstrate platelet thrombus formation on the collagen and von Willebrand factor (vWF) surface at high shear rates without significant influences on those occurring under relatively low shear rates. Because platelet thrombus formation occurring under high shear rates is known to be mediated by the vWF interaction with platelet receptor proteins GP Ibalpha and GP IIb/IIIa, we speculated that tetramethylpyrazine exerts antiplatelet effects by inhibiting the vWF-mediated process of platelet thrombus formation. Our findings, indicating the unique antiplatelet characteristics of tetramethylpyrazine, selectively inhibiting the platelet thrombus formation under high shear rates, provide good reasons for developing chemical analogs having biological functions similar to or more potent than those of tetramethylpyrazine as antiplatelet agents having unique biological functions.

Pharmacodynamic action and mechanism of volatile oil from Rhizoma Ligustici Chuanxiong Hort. on treating headache

The volatile oil from Rhizoma Ligustici Chuanxiong Hort. (CXVO) is likely to be the mainly active ingredient of Chuangxiong in curing headache. In this study, oral administration of CXVO (45.0, 90.0, and 135.0 microl/kg) to mice significantly elevated the pain threshold in the hot-plate test and reduced the number of abdominal writhing caused by acetic acid. CXVO (90.0 and 135.0 microl/kg) not only reduced locomotor activity, but also prolonged the sleeping time induced by sodium pentobarbital (35 mg/kg), and the number of mice with sleeping time over 1 min by sodium pentobarbital (25 mg/kg) was markedly enlarged by CXVO (45.0, 90.0, 135.0 microl/kg) administration. The three doses of CXVO significantly increased the pain threshold of rabbits with headache due to hot radiation and the level of plasma ET of rats with headache due to nitroglycerin injection. Besides, for the nitroglycerin-induced headache rats, the c-fos gene expression in the brain stem and hypothalamus was remarkably inhibited and the level of plasma CGRP was reduced significantly after CXVO administration at both doses 90.0 and 135.0 microg/kg. The latter dosage could also raise the level of plasma 5-HT markedly. The study suggests that CXVO acts probably as the active ingredient of Rhizoma Ligustici Chuanxiong Hort. (CX) on treating headache and has potential to be an agent for treating headache.

Effect of the water extract and ethanol extract from traditional Chinese medicinesAngelica sinensis (Oliv.) Diels,Ligusticum chuanxiong Hort. andRheum palmatum L. on rat liver cytochrome P450 activity

Angelica sinensis (Oliv.) Diels (DG), Ligusticum chuanxiong Hort. (CX) and Rheum palmatum L. (DH), three well known traditional Chinese medicines (TCM), have been used widely for the treatment of various types of disorders in China. Herb-drug interactions, especially cytochrome P450 (CYP)-mediated interactions, cause an enhancement or attenuation in the efficacy of co-administered drugs. In this study, to assess the possible interactions between TCM and drugs, the effect of water and ethanol extracts of DG, CX and DH on cytochrome P450 were studied in rats. The activities of various CYP enzymes were determined by HPLC method. Treatment of rats with water extracts or ethanol extracts of DG, CX and DH at daily dosages equivalent to 3 g (dry herbal material)/kg all increased the microsome protein contents and decreased the total CYP levels. The water extract of DG strongly increased the activities of CYP2D6 and 3A and the water extract of DH significantly increased the activity of 2D6. The other water extracts all showed inhibition against CYP isoforms. Only the ethanol extract of DG and DH increased the CYP2D6 and 3A activities, respectively, and the other ethanol extracts all decreased the level of CYP isoforms. All extract treatments had significant effects on CYP isoforms activities, whether induction or inhibition, compared with the blank control. Thus, caution should be paid to possible drug interactions of DG, CX, DH and CYP substrates.

Tetramethylpyrazine induces heme oxygenase-1 expression and attenuates myocardial ischemia/reperfusion injury in rats

The accumulation of oxygen free radicals and activation of neutrophils are strongly implicated as pathophysiological mechanisms mediating myocardial ischemia/reperfusion injury. Heme oxygenase-1 (HO-1) has been reported to play a protective role in oxidative tissue injuries. In this study, the cardioprotective activity of tetramethylpyrazine (TMP), an active ingredient of Chinese medicinal herb Ligusticum wallichii Franchat, was evaluated in an open-chest anesthetized rat model of myocardial ischemia/reperfusion injury. Pretreatment with TMP (5 and 10 mg/kg, i.v.) before left coronary artery occlusion significantly suppressed the occurrence of ventricular fibrillation. After 45 min of ischemia and 1 h of reperfusion, TMP (5 and 10 mg/kg) caused a significant reduction in infarct size and induced HO-1 expression in ischemic myocardium. The HO inhibitor ZnPP (50 microg/rat) markedly reversed the anti-infarct action of TMP. Superoxide anion production in ischemic myocardium after 10 min reperfusion was inhibited by TMP. Furthermore, TMP (200 and 500 microM) significantly suppressed fMLP (800 nM)-activated human neutrophil migration and respiratory burst. In conclusion, TMP suppresses ischemia-induced ventricular arrhythmias and reduces the infarct size resulting from ischemia/reperfusion injury in vivo. This cardioprotective activity of TMP may be associated with its antioxidant activity via induction of HO-1 and with its capacity for neutrophil inhibition.

Phthalide Lactones from Ligusticum chuanxiong inhibit lipopolysaccharide-induced TNF-alpha production and TNF-alpha-mediated NF-kappaB Activation

The dried rhizome of Ligusticum chuanxiong Hort. (Umbelliferae) is a traditional Chinese medicine (TCM) herb for the prevention and treatment of inflammatory and cardiovascular diseases. However, the role of phthalide lactones from Ligusticum chuanxiong in the therapeutic actions is not yet fully understood. In the present study, two phthalide lactones from the herb, Z-ligustilide and senkyunolide A, were identified and characterized as inhibitors of lipopolysaccharide (LPS)-induced TNF-alpha production in monocytes. The results of gene expression studies showed that the observed TNF-alpha suppression was related to their inhibitory activity on TNF-alpha mRNA transcription. Furthermore, the two phthalides exhibited significant suppressive effects on TNF-alpha-mediated nuclear factor-kappaB (NF-kappaB) activation in reporter gene assays. Taken together, the results suggest that Z-ligustilide and senkyunolide A may have potential applications in the treatment of inflammation and related diseases based on their inhibitory activity on TNF-alpha production and TNF-alpha bioactivity. New insights into the therapeutic basis of the TCM herb, Ligusticum chuanxiong, are presented.

Post-Harvest Alteration of the Main Chemical Ingredients in Ligusticum chuanxiong HORT. (Rhizoma Chuanxiong)

Rhizoma Chuanxiong (Ligusticum chuanxiong HORT.) is a commonly used traditional Chinese medicinal herb for the treatment of cardiovascular disorders. Significant variations of the main components in this herb were observed in commercial samples. The present study investigated effects of post-harvest drying and processing methods on nine main components in the herb. Results showed that drying at 60 degrees C or under the sun the contents of three major constituents, namely senkyunolide A (4), coniferylferulate (5) and Z-ligustilide (6), decreased significantly, while the contents of ferulic acid (1), riligustilide (8) and levistolide A (9) increased significantly. Senkyunolide I (2) and senkyunolide H (3), which were not detected in fresh herbs, appeared in dried samples. Similar chemical alterations, such as decrease in the contents of three major ingredients and increase in the contents of compounds 1, 2, 3, 8 and 9, were also observed in differently processed herbal samples. The possible converting mechanisms of these components were clarified by employing pure major components treated under the same conditions.

Protective effect of the ethanol extract from Ligusticum chuanxiong rhizome against streptozotocin-induced diabetic nephropathy in mice

ETHNOPHARMACOLOGY RELEVANCE

Rhizome of Ligusticum chuanxiong Hort. (Abbreviated as LC) is a frequently prescribed component in plenty of traditional Chinese medicine (TCM) formulas which are used to treat diabetic nephropathy (DN). The aims of the present study are to investigate the protective effect of the ethanol extract of LC rhizome (EEL) against DN in vivo, evaluate its potential mechanism, and find the evidence supporting its enthopharmacological use as an anti-DN agent.

MATERIALS AND METHODS

Hepa 1c1c7 murine hepatoma cells, human breast carcinoma MDA-MB-231 cells, human renal glomerular endothelial cells (HRGEC), and RAW 264.7 murine macrophages were adopted to test the effects of EEL and its active constituents on inhibitions of oxidative stress and inflammation in vitro. A streptozotocin (STZ) -induced DN C57BL/6 mice model was established and used to investigate the preventive effect of EEL against DN in vivo.

RESULTS

EEL demonstrated potential inhibitory effects against oxidative stress and inflammation in vitro. Using a STZ-induced DN mice model, it has been found that EEL treatment significantly prevented STZ-induced increases of urine production, urinary albumin excretion (UAE) and urine albumin-to-creatinine ratio (UACR), and markedly attenuated STZ-induced renal damages (e.g. glomerulosclerosis and fibrosis). The predominant bioactive constituents, Z-ligustilide (LGT), ferulic acid (FA), and tetramethylpyrazine (TMP), were inhibitors of oxidative stress and inflammation through acting with Nrf2 and NF-κB pathways.

CONCLUSIONS

EEL attenuates structural and functional damages of kidney in STZ-induced DN model in vivo, which might be related to the functions of EEL on inhibitions of oxidative stress and inflammation. These finding definitely supports the ethnopharmacological use of LC as an anti-DN agent.

Trilinear decomposition method applied to removal of three-dimensional background drift in comprehensive two-dimensional separation data

A novel technique for removal of three-dimensional background drift in comprehensive two-dimensional (2D) liquid chromatography coupled with diode array detection (LCxLC-DAD) data is proposed. The basic idea is to perform trilinear decomposition on the instrumental response data, which is based on the alternating trilinear decomposition (ATLD) algorithm. In model construction, the background drift is modeled as one component or factor as well as the analytes of interest, hence, the drift is explicitly included into the calibration. The method involves performing trilinear decomposition on the raw data, then extracting the background component and subtracting this background data from the raw data, leaving the analytes' signal on a flat baseline. Simultaneous evaluation of three-dimensional background drift and true signals may improve the quality of the data. This method is applied to the determination and removal of three-dimensional background drifts in simulated multidimensional data as well as experimental comprehensive two-dimensional liquid chromatographic data. It is shown that this technique yield a good removal of background drift, without the need to perform a blank chromatographic run, and required no prior knowledge about the sample composition.

Combination of Ligusticum chuanxiong and Radix Paeoniae ameliorate focal cerebral ischemic in MCAO rats via endoplasmic reticulum stress-dependent apoptotic signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Combination of Ligusticum chuanxiong and Radix Paeoniae (XS) is highly effective in the treatment for focal cerebral ischemic, but the underlying mechanism is not clear. This study was conducted to evaluate the combinative effects of XS on MCAO rats and explore the underlying mechanisms.

MATERIALS AND METHODS

MCAO rats were used to evaluate the protective effect of Ligusticum chuanxiong (CX), Radix Paeoniae Rubra (CS) and their combination (XS) on ameliorating focal cerebral ischemic. Cerebral ischemia deficits and infarct size were performed by 2,3,5-triphenyltetrazolium chloride (TTC) and hematoxylin-eosin (H-E) staining. Activities of SOD, CAT and GSH-Px, as well as levels of LPO and MDA were detected by commercial kits while ELISA kits for the content of plasminogen activator inhibitor-1 (PAI-1) and plasminogen activator (PA). Immunohistochemistry (IHC) and western blot analysis (WB) were carried out to examine the protein expressions including PKR-like endoplasmic reticulum kinase (PERK), cytoplasmic of glucose regulated protein 78 (GRP78), X box-binding protein-1 (XBP-1), activating transcription factor-6 (ATF-6), C/EBP-homologous protein (CHOP), metalloprotease-9 (MMP-9), tissue inhibitor of metalloproteinase-1 (TIMP-1), Bcl-2 associated X protein (Bax), and porcineB-cellleukemia/lymphoma-2 (Bcl-2) in brain tissues. Reverse transcription polymerase chain reaction (RT-PCR) and Quantitative PCR (Q-PCR) were applied to examine vascular endothelial growth factor (VEGF) and N-methyl-d-aspartate receptors (NMDAR1) mRNA levels.

RESULTS

CX, CS and their combination (XS) could reduce cerebral ischemia deficits and infarct size of MCAO rats. They increased SOD, CAT and GSH-Px activities, and reduced MDA and LPO levels in serum, markedly. A significant decrease of endoplasmic reticulum stress-related factors PERK, XBP-1, ATF-6 and CHOP protein expression levels while an increase of GRP78 and MVD expression by the treatment of CX, CS and XS. It could also be observed that their treatment could reduce apoptotic damage of brain tissues by up-regulating Bax level and down-regulating Bcl-2 level. Furthermore, the levels of MMP-9 and PAI-1 in serum and tissues of rats were down-regulated remarkably while TIMP-1 and PA levels were up-regulated. VEGF mRNA level was up-regulated dramatically whereas NMDAR1 was reduced. Importantly, the combination of CX and CS, namely XS, has a more meaningful improvement on focal cerebral ischemic than CX or CS alone.

CONCLUSION

All these revealed that the combined XS exerted more remarkable protective effects than alone. XS could inhibit neuronal apoptosis by attenuating ER-stress-dependent apoptotic signaling and protected the blood-brain barrier. These findings might supply beneficial hints for the synergy of CX and CS, and provide the basis for rationality of XS preparation and deserve further clinical investigations.

Development of pressurized hot water extraction followed by headspace solid-phase microextraction and gas chromatography-mass spectrometry for determination of ligustilides inLigusticum chuanxiongand Angelica sinensis

In this work, a simple, rapid, solvent-free, and low-cost method was developed for the determination of ligustilides in traditional Chinese medicines (TCMs), which was based on pressurized hot water extraction (PHWE) followed by headspace solid-phase microextraction (HS-SPME) and gas chromatography-mass spectrometry (GC-MS). The two bioactive compounds Z-ligustilide and E-ligustilide in two common TCMs, viz. Ligusticum chuanxiong and Angelica sinensis, were extracted by water at 150 degrees C and 40 bar, followed by concentration with HS-SPME and detection by GC-MS. PHWE and HS-SPME parameters were investigated and method validation (precision and recovery) was studied. It has been shown that the proposed method provides a powerful approach for quantitative analysis of ligustilides in TCMs. The method was applied to determination of ligustildes in the TCMs from different growing areas. The results indicate that PHWE-HS-SPME-GC-MS is a potential tool for TCM quality assessment.

Studies on antiproliferative effects of phthalides from Ligusticum chuanxiong in hepatic stellate cells

Suppression of hepatic stellate cell (HSC) growth and activation, and induction of apoptosis, have been proposed as therapeutic strategies for the treatment and prevention of liver fibrosis. Our previous study showed that the Chinese herb Ligusticum chuanxiong (LC) inhibits platelet-derived growth factor (PDGF-BB)-induced HSC proliferation. The present study was designed to investigate the active principles and their action mechanisms. With a bioactivity-directed fractionation approach, DNA synthesis (bromodeoxyuridine (BrdU) incorporation), cell cycle related proteins and apoptosis markers were determined to evaluate the inhibitory effects of active principles of LC. Two phthalides, Z,Z'-6,8',7,3'-diligustilide (1) and levistolide A (2), from LC significantly abrogated PDGF-BB-induced proliferation in both rat and human HSC lines. These inhibitory effects of compounds 1 and 2 were associated with reduction of alpha-smooth muscle actin and collagen expressions. The cell cycle promoting proteins, cyclins D1, D2, E, A and B1, were downregulated while the inhibitory proteins p21 and 27 were up-regulated. JNK phosphorylation was up-regulated by compounds 1 and 2. In HSC-T6, the two compounds induced apoptosis through the activation of caspases 9 and 3, increase in cytosolic cytochrome c release, and downregulation of Bcl-2 and Akt phosphorylation. Moreover, neither phthalides caused direct cytotoxicity to either HSCs or rat primary hepatocytes under experimental concentrations. These results indicate that two phthalides from LC inhibited PDGF-BB-activated HSC proliferation possibly through cell cycle inhibition and apoptosis mechanisms. They might be potential anti-fibrotic drugs for the treatment and prevention of hepatic fibrosis.

Characterization of Phthalides in Ligusticum chuanxiong by Liquid Chromatographic-Atmospheric Pressure Chemical Ionization-Mass Spectrometry

High-performance liquid chromatography (HPLC) with diode-array detection interfaced to atmospheric pressure chemical ionization (APCI)-mass spectrometry (MS) is applied to analyze phthalides from Chuanxiong (the rhizome of Ligusticum chuanxiong). This herb material, containing plenty of phthalide compositions, is selected as the analytical target in this paper for its hematological activity. Some of the phthalides are not stable and are difficult to analyze by gas chromatography-MS. Under optimized LC-MS-MS conditions, six phthalides in the methanol extract of Chuanxiong are unambiguously identified, and characteristic fragments are obtained using homemade reference standards. Ten other phthalides in the extract are confirmed by means of LC-APCI-MS with positive-negative ion mode and collision-induced dissociation in combination with UV spectrophotometry. The results show that LC-MS-MS is a method of choice for fast detection and detailed structural analysis of such mixtures in the crude extract of Chuanxiong.

Analysis of the chemical composition, acute toxicity and skin sensitivity of essential oil from rhizomes of Ligusticum chuanxiong

ETHNOPHARMACOLOGICAL RELEVANCE

Ligusticum chuanxiong Hort. (Umbelliferae) is a plant used as medicine and food in China. The essential oil (EO) extracted from its rhizomes possesses many pharmacological activities. However, there have been no scientific reports in the modern literature on the safety of EO.

AIMS OF THE STUDY

The objective of this study was to conduct a chemical composition analysis and evaluate acute toxicity and skin sensitivity of EO from rhizomes of Ligusticum chuanxiong.

MATERIALS AND METHODS

The chemical composition of hydrodistilled EO was analyzed by gas chromatography-mass spectrometry (GC-MS) and was evaluated in animals for acute toxicity, skin irritation and sensitization tests.

RESULTS

Dozens of compounds were detected and the major components of EO were ligustilide and butylidenephthalide with relative contents of 67.46 and 5.06%, respectively. The oral and intra-peritoneal lethal doses of 50% (LD(50)) in mice were 7.23 g/kg (approximately 14,606 times of clinical dose used) and 2.25 g/kg (approximately 5091 times of clinical dose used), respectively. The doses of 0.115 and 0.23 g/kg EO (approximately 232.5 and 465 times of the respective clinical doses used) revealed slight irritation effects on rabbit skin, but 1g/kg EO (approximately 2020 times of clinical dose used) had no observable effect on guinea pig skin in the skin sensitization test.

CONCLUSIONS

These experimental results indicate that short term application of EO is probably safe within the range of its clinical doses, but the dose should be controlled for external use due to its slight skin irritation.

Separation and identification of the organic acids in Angelicae Radix and Ligustici Rhizoma by HPLC and CE

Angelicae Radix (AR) and Ligustici Rhizoma (LR) are both derived from the Umbelliferae plants and contain similar organic acids as their bioactive compounds. Nine of these organic acids, including nicotinic acid, protocatechuic acid, phthalic acid, folinic acid, p-hydroxybenzoic acid, folic acid, vanillic acid, caffeic acid, and ferulic acid were separated by HPLC and CE. Detection at 210 nm with a linear gradient containing 20 mM KH2PO4 (pH 3.5) and H2O-CH3CN in HPLC and with a buffer solution containing 10 mM LTAC, 2 mM Na2HPO4, 9 mM Na2B4O7(pH 9.56), and CH3CN in CE were found to be the most efficient eluents for this separation. The contents of the nine components in crude extracts of either AR or LR could easily be determined within 60 min by LC and within 20 min by CE. The structures of the individual peaks in the LC chromatogram were identified by LC-MS. The effects of buffers on the separation and validation of the two methods were examined.

Inhibition of rat vascular smooth muscle cell proliferation by extract of Ligusticum chuanxiong and Angelica sinensis

Ligusticum chuanxiong (LC) and Angelica sinensis (AS) have been widely used as traditional Chinese medicine to treat some pathological settings such as atherosclerosis and hypertension. The aim of this paper is to determine the effects of the extract of LC and AS (ELCAS) on serum-induced vascular smooth muscle cell (VSMC) proliferation, cell cycle and nitric oxide production. The results show that ELCAS significantly inhibited proliferation and protein synthesis of VSMC in a dose and time dependent manner. The cell population assessed by flow cytometry in the G(0)/G(1) phase increased 74% versus 79.8%, concomitant with a decrease in the S phase, 7.4% versus 4.2%, for control versus ELCAS (300 microg/ml). On the other hand, ELCAS significantly increased nitric oxide production of VSMC. The data suggest that ELCAS markedly inhibited VSMC proliferation by arresting G(1) to S progression, which may be associated with nitric oxide production.

Pharmacokinetics, tissue distribution and metabolism of senkyunolide I, a major bioactive component in Ligusticum chuanxiong Hort. (Umbelliferae)

ETHNOPHARMACOLOGICAL RELEVANCE

Ligusticum chuanxiong Hort. (Umbelliferae) is widely prescribed for treatment of cardiovascular diseases in China for centuries. One of the major bioactive components in L. chuanxiong is senkyunolide I (SEI), which shows pharmacological activities in anti-migraine and anti-oxidative damage.

MATERIALS AND METHODS

The aim of this study was to investigate in vivo pharmacokinetics, tissue distribution and metabolism of SEI in rats. The concentrations of SEI in plasma and tissues were determined by a high performance liquid chromatography (HPLC) method, and the pharmacokinetic parameters were calculated using and non-compartmental analysis. The metabolites were identified using high performance liquid chromatography tandem mass (HPLC-ESI-MS/MS) method.

RESULTS

After oral and intravenous administration, SEI was quickly eliminated from plasma and its oral bioavailability (BA) was about 37.25%, which was smaller than intraportal BA (81.17%), but similar to intraduodenal BA (36.91%), suggesting that gastric first-pass effect of SEI is negligible, and hepatic first-pass effect was approximately 18.83%. After oral administration, SEI could penetrate blood brain barrier and extensively distribute in tested tissues, with the descending order of AUC being kidney, liver, lung, muscle, brain, heart, thymus, and spleen in rat. The parent compound and nine metabolites were found and identified in rat bile after oral administration of SEI (36 mg/kg). The metabolic mechanism of SEI in rat mainly involves methylation, glucuronidation and glutathione conjugation during the phase II biotransformation pathway in rats.

CONCLUSIONS

The information gained here may provide a meaningful basis for clinical application of such a bioactive compound of herbal medicines.