Oren-gedoku-to and Keishi-bukuryo-gan-ryo Inhibit the Progression of Atherosclerosis in Diet-Induced Hypercholesterolemic Rabbits

Reshaping the gut microbiome and bile acid composition by Gyejibongnyeong-hwan ameliorates western diet-induced dyslipidemia

Gyejibongnyeong-hwan (GBH), a traditional Chinese medicine, is used in clinical practice to treat blood stasis in metabolic diseases. Herein, we examined the effects of GBH on dyslipidemia and investigated the underlying mechanisms by focusing on modulation of the gut microbiota-bile acid axis by GBH. We utilized a Western diet-induced dyslipidemia mouse model and divided animals into the following four groups (n = 5 each): the normal chow diet, vehicle control (WD), simvastatin (Sim, 10 mg/kg/day simvastatin; positive control), and GBH (GBH, 300 mg/kg/day) groups. The drugs were administered for 10 weeks, and morphological changes in the liver and aorta were analyzed. The mRNA expression of genes related to cholesterol metabolism, gut microbiota, and bile acid profiles were also evaluated. The GBH group showed significantly lower levels of total cholesterol, accumulation of lipids, and inflammatory markers in the liver and aorta of Western diet-fed mice. Low-density lipoprotein cholesterol levels were significantly lower in the GBH group than in the WD group (P < 0.001). The expression of cholesterol excretion-associated genes such as liver X receptor alpha and ATP-binding cassette subfamily G member 8, as well as the bile acid synthesis gene cholesterol 7 alpha-hydroxylase, which lowers cholesterol in circulation, was increased. Furthermore, GBH inhibited the intestinal farnesoid X receptor (FXR)-fibroblast growth factor 15 signaling pathway through the interactions of gut microbiota with bile acids acting as FXR ligands, which included chenodeoxycholic acid and lithocholic acid. Overall, GBH improved dyslipidemia induced by a Western diet by modulating the gut microbiota-bile acid axis.

Live-Imaging Analysis of Target Vessels and Nitric Oxide Production Associated with Gosha-Jinki-Gan and Keishi-Bukuryo-Gan: Two Herbal Preparations with Clinically Proven Blood Flow-Improving Effects but with Different Traditional Clinical Indicative Patterns

Gosha-jinki-gan (GJG) and Keishi-bukuryo-gan (KBG) are Kampo traditional herbal prescriptions used for different clinical patterns (sho) that improve blood flow. The pharmacological basis of the therapeutic choice remains unclear, although the clinical reliance of this pattern-based therapy is widely proven. We aimed to investigate their effects on microcirculation and nitric oxide (NO) kinetics using a live-imaging system to provide evidence for this. Live-imaging was performed in murine subcutaneous vessels and rat mesentery. In the subcutaneous vessels, we analyzed the effects of both drugs on the vessel diameter, blood flow velocity, and volume in the arteries, arterioles, and capillaries. In the rat mesentery, we induced the “oketsu” blood stasis using a stack of thin vinylidene chloride films and examined the effect on NO production using a fluorescent diaminofluorescein-2 diacetate. Following dissolution in hot water, 300 mg/kg of both drugs were administered intragastrically via a transesophageal catheter. Live-imaging analysis of subcutaneous blood flow revealed the different effects of GJG and KBG on their target vessels and effect onset. GJG targeted the capillaries and progressively increased the blood flow velocity and rate at 30–120 min after administration. No vasodilation or increased blood flow in the arteries and arterioles occurred. In contrast, KBG increased the diameter of the arterioles and arteries at 30–90 min after administration, and increased blood flow velocity and rate in arteries and arterioles. In a model of oketsu blood stasis in the mesenteric arteries, KBG increased the NO production from the vascular endothelial cells with dilatation of the arteriolar diameter. GJG improved blood flow mainly in the capillaries. Endothelial NO production decreased after GJG administration. The empirical treatment choice between GJG and KBG is based on the difference in target vessels and NO action and provides a pharmacological basis for therapy based on traditional medicine.

A Review on the Mechanism and Application of Keishibukuryogan

The concept of "blood stasis" - called yū xiě in Chinese, Oketsu in Japanese - is one of the unique pathophysiology of traditional medicine that originated in China and inherited in Korea and Japan. This concept is related to the multiple aspects of hemodynamic disorders brought on by quantitative and qualitative changes. It theorizes that the quantitative changes of "blood stasis" are related to peripheral circulatory insufficiency. When chronic qualitative changes of "blood stasis" produce stagnant blood that turns into a pathological product, it could cause inflammation and lead to organic changes. Trauma induced hematomas, that are considered to be a quantitative change of blood, are also a form of blood stasis. The basic medicine research on Keishibukuryogan (KBG)-a Japanese name in Traditional Japanese Medicine (Kampo) for one of the most common anti- "blood stasis" prescriptions, also known as gui-zhi-fu-ling-wan (GFW) in Chinese in Traditional Chinese Medicine (TCM)-indicated that the initiation of quantitative changes was closely related to loss of redox balances on endothelial function induced by oxidative stress. The following qualitative changes were related to coagulopathy, hyper viscosity; anti-platelet aggregation, lipid metabolism; a regulation of systemic leptin level and/or lipid metabolism, inflammatory factor; cyclooxygenase-1,2 (COX-1, 2), interleukin-6, 8 tumor necrosis factor-α, macrophage infiltration, hyperplasia, tissue fibrosis and sclerosis caused by transforming growth factor-β1 and fibronectin, the dysfunction of regulated cell deaths, such as, apoptosis, autophagy, ferroptosis and ovarian hormone imbalance. Clinically, KBG was often used for diseases related to Obstetrics and Gynecology, Endocrine Metabolism, Rheumatology and Dermatology. In this review, we give an overview of the mechanism and its current clinical application of KBG through a summary of the basic and clinical research and discuss future perspective.

Integrated Network Pharmacology and Metabonomics to Reveal the Myocardial Protection Effect of Huang-Lian-Jie-Du-Tang on Myocardial Ischemia

Myocardial ischemia (MI) is one of the most common cardiovascular diseases with high incidence and mortality. Huang-Lian-Jie-Du-Tang (HLJDT) is a classic traditional Chinese prescription to clear “heat” and “poison”. In this study, we used a deliberate strategy integrating the methods of network pharmacology, pharmacodynamics, and metabonomics to investigate the molecular mechanism and potential targets of HLJDT in the treatment of MI. Firstly, by a network pharmacology approach, a global view of the potential compound-target-pathway network based on network pharmacology was constructed to provide a preliminary understanding of bioactive compounds and related targets of HLJDT for elucidating its molecular mechanisms in MI. Subsequently, in vivo efficacy of HLJDT was validated in a rat model. Meanwhile, the corresponding metabonomic profiles were used to explore differentially induced metabolic markers thus providing the metabolic mechanism of HLJDT in treating MI. The results demonstrated the myocardial protection effect of HLJDT on ischemia by a multicomponent-multitarget mode. This study highlights the reliability and effectiveness of a network pharmacology-based approach that identifies and validates the complex of natural compounds in HLJDT for illustrating the mechanism for the treatment of MI.

Effectiveness and safety of Hwangryunhaedok-Tang (Huang-Lian-Jie-Du-Tang, Oren-Gedoku-to) for dyslipidemia: A protocol for a PRISMA-compliant systematic review and meta-analysis

BACKGROUND

Recent experimental and clinical studies have suggested that Hwangryunhaedok-tang (HHT), an herbal formula, could improve the lipid profiles in patients with dyslipidemia. This systematic review aimed to evaluate the effectiveness and safety of HHT monotherapy or adjunctive HHT therapy with conventional lipid-lowering drugs in managing dyslipidemia.

METHODS

Twelve English, Korean, Chinese, and Japanese databases were comprehensively searched from their inception to January 2020. Randomized controlled trials (RCTs) using HHT monotherapy or adjunctive HHT therapy for dyslipidemic patients were included. The primary outcome was the low-density lipoprotein cholesterol (LDL-C) level. Descriptive analyses of participant details, interventions, and outcomes were conducted and where appropriate data were available, a meta-analysis was performed and presented as a risk ratio (RR) or mean difference (MD) with 95% confidence intervals (CIs). The risk of bias was assessed using the Cochrane risk of bias tool and the quality of evidence was evaluated using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach.

RESULTS

Nine RCTs with 536 participants were included. In comparison with lipid-lowering drugs alone, HHT as an adjunctive therapy to lipid-lowering drugs or as a monotherapy showed significantly superior (MD -1.15 mmol/L, 95% CI -1.25 to -1.05) or inferior results (MD 0.23 mmol/L, 95% CI 0.09 to 0.38), respectively, for LDL-C levels. The incidence of adverse events was significantly lower when HHT was used in addition to lipid-lowering drugs, in comparison to that with lipid-lowering drugs alone. No serious adverse events were reported in the HHT group. Most included studies showed a high risk of performance bias and the quality of evidence was rated generally "low" because of the high risk of bias and inconsistency or imprecision of the meta-analysis results.

CONCLUSION

Current evidence suggests that HHT may be beneficial for patients with dyslipidemia and may reduce the adverse events associated with lipid-lowering drugs. However, due to the high risk of bias of the included studies and low quality of evidence for the main findings, no definitive conclusion could be reached. Further rigorous, high-quality, and placebo-controlled RCTs should be conducted to assess the efficacy of HHT.

TRIAL REGISTRATION NUMBER

PROSPERO CRD42020164563.

Efficacy of Hwangryunhaedok-tang (Huang-lian-jie-du-tang, Oren-gedoku-to) for patients with hyperlipidemia: a study protocol for a randomized, double-blind, placebo-controlled, parallel, investigator-initiated clinical trial

BACKGROUND

The prevalence of hyperlipidemia continues to increase due to aging and lifestyle changes. Statins are currently used as the first choice for treating hyperlipidemia, but are limited by adverse reactions. Hwangryunhaedok-tang (HHT) has received attention as a promising intervention for hyperlipidemia through a few experimental and clinical trials. This study aims to explore the feasibility, effectiveness, and safety of HHT for hyperlipidemia treatment.

METHODS

This is a study protocol for a randomized, double-blind, placebo-controlled, parallel, investigator-initiated, pilot clinical trial held in Daejeon, Republic of Korea. Thirty patients with hyperlipidemia will be randomly allocated to HHT or placebo granule groups in equal proportions. Participants will be administered HHT or placebo granules three times per day for 8 weeks and followed up for another 4 weeks. The primary outcome is low-density lipoprotein cholesterol at 8 weeks from the commencement of treatment. Other blood lipid parameters, biomarkers of atherosclerosis, the degree of arteriosclerosis, blood glucose parameters, blood pressure, anthropometric parameters, health-related quality of life, and the changes in the general symptoms of cold and hot patterns will be measured as secondary outcomes. Adverse events and laboratory test results will be investigated to assess the safety. Changes in the gut microbiome before and after intervention will also be assessed as an exploratory outcome through next-generation sequencing. Data will be recorded in electronic case report forms and analyzed using SAS® Version 9.4.

DISCUSSION

This is a rigorously designed pilot clinical trial to explore the effect and safety of Hwangryunhaedok-tang compared to placebo control for patients with hyperlipidemia, thereby potentially facilitating better management of hyperlipidemia. The results of this pilot study could form the foundation for a future large-scale, confirmatory clinical trial.

TRIAL REGISTRATION

Clinical Research Information Service KCT0004564 . Registered on December 18, 2019.

Genotoxicity evaluation of Hwanglyeonhaedok-tang, an herbal formula

ETHNOPHARMACOLOGICAL RELEVANCE

Hwanglyeonhaedok-tang (Huanglianjiedu-tang, Orengedoku-to), a traditional herbal formula, is used for the treatment of inflammatory, gastrointestinal and cardiovascular diseases.

PURPOSE

The purpose of this study was to evaluate the genotoxic potential of Hwanglyeonhaedok-tang water extract (HLHDT).

METHODS

A genotoxicity test was conducted using a bacterial reverse mutation test (Ames test), an in vitro chromosome aberration test using Chinese hamster lung cells, and an in vivo micronucleus test using ICR mouse bone marrow.

RESULTS

In the Ames test, which used different Salmonella typhimurium (S. typhimurium) and Escherichia coli (E. coli) strains, HLHDT did not increase the number of revertant colonies of S. typhimurium strains TA98, TA100 and TA1535 as well as E. coli strains with or without S9 mix. However, the number of revertant colonies with the S. typhimurium TA1537 strain and S9 mix increased in a dose-dependent manner. The chromosome aberration test showed that HLHDT did not increase the number of structural or numerical chromosome aberrations in a short-period test (6h) with S9 mix. By contrast, HLHDT significantly increased the number of structural chromosome aberrations in a short-period (6h) or continuous (22h) test without S9 mix. In the micronucleus test, no significant increase was observed in micronucleated polychromatic erythrocytes, and no significant decrease was observed in polychromatic to total erythrocytes.

CONCLUSIONS

These results indicate that HLHDT might be genotoxic, based on both the Ames and chromosome aberration tests. Therefore, further in vivo studies will be needed to define the mechanism of this genotoxicity.

Transcriptomics Analysis of Candida albicans Treated with Huanglian Jiedu Decoction Using RNA-seq

Candida albicans is the major invasive fungal pathogen of humans, causing diseases ranging from superficial mucosal infections to disseminated, systemic infections that are often life-threatening. Resistance of C. albicans to antifungal agents and limited antifungal agents has potentially serious implications for management of infections. As a famous multiherb prescription in China, Huanglian Jiedu Decoction (HLJJD, Orengedokuto in Japan) is efficient against Trichophyton mentagrophytes and C. albicans. But the antifungal mechanism of HLJDD remains unclear. In this study, by using RNA-seq technique, we performed a transcriptomics analysis of gene expression changes for C. albicans under the treatment of HLJDD. A total of 6057 predicted protein-encoding genes were identified. By gene expression analysis, we obtained a total of 735 differentially expressed genes (DEGs), including 700 upregulated genes and 35 downregulated genes. Genes encoding multidrug transporters such as ABC transporter and MFS transporter were identified to be significantly upregulated. Meanwhile, by pathway enrichment analysis, we identified 26 significant pathways, in which pathways of DNA replication and transporter activity were mainly involved. These results might provide insights for the inhibition mechanism of HLJDD against C. albicans.

Induced cortical neurogenesis after focal cerebral ischemia--Three active components from Huang-Lian-Jie-Du Decoction

ETHNOPHARMACOLOGICAL RELEVANCE

Huang-Lian-Jie-Du-Decoction (HLJDD) is a Traditional Chinese Medicine (TCM) clinical prescription noted for its neuroprotective effects. The total alkaloids, flavonoids, and iridoids are the main active components of HLJDD. In the present study we explored the possible effects of the total alkaloids, flavonoids, and iridoids from HLJDD on behavioral recovery and cortical neurogenesis after stroke.

METHODS

The stroke model was induced by permanent middle cerebral artery occlusion (pMACO). The total alkaloids (44 mg/kg), flavonoids (50 mg/kg), and iridoids (80 mg/kg) from HLJDD were orally administered for 2h after stroke and daily thereafter. Neurological function was assessed and then rats were sacrificed 7 days after pMACO. Following repeated intraperitoneal injections of the cell proliferation - specific marker 5-bromodeoxyuridine (BrdU) after stroke induction, precursor cell proliferation and differentiation was monitored by immunofluorescent staining. The levels of relevant proteins were determined by western blotting and the mRNA expressions were assessed by quantitative real time-polymerase chain reaction (qRT-PCR).

RESULTS

Total alkaloids, flavonoids and iridoids from HLJDD showed improved functional outcome after brain ischemia. The total alkaloids and iridoids increased number of BrdU-positive cells and enhanced neuronal differentiation in the cortex. Alkaloids-enhanced neurogenesis might be associated with increased VEGF, Ang-1, and Ang-2 protein expression. And the neuroproliferative effect of alkaloids was partially correlated with increased phosphorylation of AKT, and GSK-3β. Flavonoids treatment was found to promote differentiation of cortical precursor cells into neuronal but not glial cells, which may be at least attributable to the regulation of AKT, GSK-3β mRNA and Ang-1 protein levels.

CONCLUSIONS

Total alkaloids, iridoids and flavonoids from HLJDD promoted functional recovery likely via enhancing cortical neurogenesis and thus have potential as a treatment for ischemic brain injury.

Inhibition of eukaryotic elongation factor-2 confers to tumor suppression by a herbal formulation Huanglian-Jiedu decoction in human hepatocellular carcinoma

ETHNOPHARMACOLOGICAL RELEVANCE

An oriental medicinal formulation, Huanglian Jiedu Decoction (HLJDD), has been well documented in few Traditional Chinese Medicine Classics 1300 years ago for treatment of heat and dampness-related diseases. Its effect is well accepted in Asian community, including China, Japan and Korea. Recent studies have postulated HLJDD as a regimen for cancer treatment, especially liver cancer, but the underlying mechanism is unknown. The aim of this study was to examine the suppressive effect of HLJDD on the growth of hepatocellular carcinoma (HCC) and its possible underlying mechanism.

METHODS

Chemical composition of HLJDD was analyzed by high performance liquid chromatography. The tumor suppressive effect of HLJDD was determined on both HCC cells and xenograft model. Nascent protein synthesis was detected with Click-IT protein labeling technology; protein expression was determined by immunoblotting and imunnohistochemical analysis.

RESULTS

Quality analysis revealed that HLJDD of different batches is consistent in both chemical composition and bioactivities. HLJDD inhibited HCC cell proliferation at its non-toxic doses, and suppressed growth and angiogenesis in xenografted murine model. HLJDD suppressed the synthesis of nascent protein via inactivation of eEF2 without deregulating the translation initiation factors. The major components in HLJDD, geniposide, berberine and baicalin, additively act on eEF2, and contributed to the responsible activity. HLJDD-activated eEF2 kinase (eEF2K) led to eEF2 inactivation, and activation of AMPK signaling may be responsible for the eEF2K induction. Blocked AMPK activity in HLJDD-treated HCC cells attenuated eEF2K activation as well as the inhibitory effect of the formula. In nutrient deprived HCC cells with inactivated eEF2, the inhibitory effect of HLJDD in tumor cell expansion was interfered.

CONCLUSION

Our results indicate that HLJDD has potential in blocking HCC progression with involvement of eEF2 inhibition.

Simultaneous quantification and antiatherosclerosis effect of the traditional Korean medicine, Hwangryunhaedok-tang

Background

Hwangryunhaedok-tang (HHT) is a traditional herbal medicine that is used for the treatment of fever, inflammation, gastritis, and hypertension. In this study, we performed simultaneous determination of the five components, geniposide (1), baicalin (2), coptisine (3), palmatine (4), and berberine (5) in HHT by using a high-performance liquid chromatography–photodiode array (HPLC–PDA) analysis. We also evaluated the antioxidative activity of HHT and compounds 1–5 by measuring their effects on low-density lipoprotein (LDL) oxidation and antiproliferative abilities in vascular smooth muscle cells (VSMCs).

Methods

Five compounds were separated within 40 min by using a Gemini C₁₈ column (temp. 35°C; two-component gradient elution; flow rate 1.0 mL/min; detector 240 and 277 nm). The activities of HHT and compounds 1–5 were tested with the radical scavengers 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt and 2,2-diphenyl-1-picrylhydrazyl, in thiobarbituric acid reactive substance assays, and in relative electrophoretic mobility assays using CuSO₄-induced LDL oxidation systems. The antiproliferative effects of samples on platelet-derived growth factor (PDGF)-induced VSMC proliferation were studied by using a cell proliferation assay.

Results

Regression analysis of the five major compounds showed good linearity (r² ≥ 0.9997) in different concentration ranges. The recoveries of the five compounds were in the range 86.31–110.78%, with relative standard deviations below 2.1%; those of intra- and interday precision were 0.04–3.78% and 0.04–1.69%, respectively. HHT reduced the oxidation properties of LDL induced by CuSO₄ and inhibited cell proliferation in PDGF-treated VSMCs. Among the five components, compound 2 could effectively suppress LDL oxidation and PDGF-induced VSMC proliferation.

Conclusions

The established HPLC–PDA method will help to improve quality control of HHT. The results demonstrate that HHT has antiatherosclerotic activity and that it functions by modulating LDL oxidation and VSMC proliferation. The effects of HHT may be attributed, at least I part, to compound 2.

Extracts of Scutellariae Radix inhibit low-density lipoprotein oxidation and the lipopolysaccharide-induced macrophage inflammatory response

Traditional herbal formulas made from Scutellariae Radix (SR), the root of Scutellaria baicalensis, have previously been used in the treatment of inflammatory diseases, such as atherosclerosis. The aim of the present study was to investigate the effects of SR on low-density lipoprotein (LDL) oxidation and inflammation in macrophages, which are early events in the development of atherosclerosis. High-performance liquid chromatography photo-diode array analysis was used to obtain a three-dimensional chromatogram of SR. The antioxidative effects of SR were evaluated by determining its scavenging activities against ABTS and DPPH radicals. The inhibitory effect of SR on LDL oxidation was examined using a thiobarbituric acid-reactive substance assay and a relative electrophoretic mobility assay. In addition, the anti-inflammatory effects of SR were evaluated in lipopolysaccharide (LPS)-induced RAW264.7 murine macrophage cells. The results showed that SR exhibited radical-scavenging activities in a dose-dependent manner; in addition, SR attenuated the Cu2+-induced oxidation of LDL as well as significantly inhibited nitric oxide (NO) production and inducible NO synthase (iNOS) expression in LPS-induced RAW264.7 cells. Furthermore, SR induced the protein expression of heme oxygenase-1 (HO-1) in RAW264.7 cells. In conclusion, the results of the present study demonstrated that SR decreased the oxidation of LDL and suppressed inflammatory responses in macrophages, which occurred at least in part via the induction of HO‑1. These results therefore suggested that SR may be a potential therapeutic agent for the treatment of atherosclerosis.

Inhibiton of cytochrome P450 isoenzymes and P-gp activity by multiple extracts of Huang-Lian-Jie-Du decoction

ETHNOPHARMACOLOGICAL RELEVANCE

Huang-Lian-Jie-Du-Decotion (HLJDD), an important traditional Chinese medicine formula, has been used for various diseases in clinical practice, and thus has high potential to induce cytochrome P450 (CYP) isoenzymes/P-glycoprotein (P-gp) mediated herb-drug interactions (HDIs) with other co-administered drugs. The purpose of this study was to investigate the in vitro effects of multiple extracts including aqueous extracts, total flavonoids, iridoids, alkaloids from HLJDD on the activities of CYPs in rats (CYP1A2, CYP2C6, CYP2D2, CYP2E1 and CYP3A1) and P-gp, and then to predict potential interactions with co-administered drugs.

MATERIALS AND METHODS

The effects of the four extracts from HLJDD on the CYPs activity were evaluated in rat liver microsomes incubation system, and then determined by LC-MS/MS-based CYPs probe substrate assay. Caco-2 cell monolayer was used to investigate the effect of the four extracts on the efflux of Rhodamine 123 to evaluate their influences on P-gp activity.

RESULTS

The results show that total flavonoids and alkaloids exibited strong inhibition on rat CYP isoenzymes activities. Total flavonoids exhibited different inhibitory effects on CYPs activities with an order of CYP3A1>CYP2C6>CYP2E1>CYP1A2>CYP2D2, and the values of IC₅₀ were 4.24, 8.16, 17.56, 19.03, 29.51 μg/mL, respectively. Total alkaloids possessed similar inhibition on CYPs and could strongly inhibit the activity of CYP2D2 (IC₅₀=2.38 μg/mL), CYP3A1 (IC₅₀=2.61 μg/mL), CYP2E1 (IC₅₀=22.35 μg/mL), CYP1A2 (IC₅₀=23.2 μg/mL) and CYP2C6 (IC₅₀=43.09 μg/mL). Moderate degree of inhibition on CYPs activities was observed in aqueous and total iridoids extracts. Results from transport assay revealed that total flavonoids and alkaloids exhibited significant inhibitory effect on P-gp activity as evidenced by strong inhibition on the efflux of Rhodamine-123 with IC₅₀ of 104.6 and 82.6 μg/mL. But aqueous extract showed weak and iridoids had negligible effect on P-gp activity.

CONCLUSIONS

This study clearly demonstrated that total flavonoids and alkaloids from HLJDD can significantly inhibit the activities of CYPs and P-gp, which should be taken into consideration to predict any potential HDIs when HLJDD and its bioactive components are co-administered with other therapeutic drugs metabolized by CYPs or transported by P-gp.

Comparative pharmacokinetic investigation on baicalin and wogonoside in type 2 diabetic and normal rats after oral administration of traditional Chinese medicine Huanglian Jiedu decoction

ETHNOPHARMACOLOGICAL RELEVANCE

Huanglian Jiedu decoction (HLJDD) is used traditionally in China for the treatment of diabetes mellitus in clinical practice, which has been proved to be effective. The purpose of this study was to investigate the pharmacokinetic characteristics (especially the area under the curve, AUC) of baicalin and wogonoside in type 2 diabetic rats after oral administration of HLJDD extract and to explore its possible mechanism.

MATERIALS AND METHODS

HLJDD extract and Radix scutellariae extract were prepared and the contents of baicalin and wogonoside contained in two extracts were assayed with high performance liquid chromatography (HPLC). Type 2 diabetic rats were induced by high fat diet and intraperitoneal injection of streptozotocin. Pharmacokinetics of baicalin and wogonoside in type 2 diabetic and normal control rats after oral administration of HLJDD extract or Radix scutellariae extract were investigated. Pharmacokinetics of baicalin in type 2 diabetic and normal rats after oral administration of pure baicalin was also investigated.

RESULTS

The pharmacokinetic parameters (especially AUCs) of baicalin and wogonoside in type 2 diabetic rats after oral administration of HLJDD extract were remarkably different from those in normal rats. And the alterations of the AUCs of baicalin and wogonoside in type 2 diabetic rats after oral administration of Radix scutellariae extract were similar to those after oral administration of HLJDD extract. Moreover, the increase of the AUC of baicalin in type 2 diabetic rats after oral administration of pure baicalin was similar to that after oral administration of HLJDD extract or Radix scutellariae extract.

CONCLUSION

The pharmacokinetic behaviors of baicalin and wogonoside (especially the systemic exposure [AUCs] of baicalin and wogonoside) were significantly altered in type 2 diabetic rats after orally administrated HLJDD extract. And the increased AUCs of baicalin and wogonoside in type 2 diabetic rats after oral administration of HLJDD extract resulted from neither the effects of other herbs contained in HLJDD nor the effects of other components contained in Radix scutellariae. It might result from the effects of the pathological status of type 2 diabetes mellitus.

Hypolipidemic effect of the Chinese polyherbal Huanglian Jiedu decoction in type 2 diabetic rats and its possible mechanism

Huanglian Jiedu Decoction (HLJDD) is used traditionally in China for the treatment of diabetes mellitus in clinical practice, which has been proved to be effective. In present investigation, the 3D-HPLC fingerprint of HLJDD and the contents of main components (namely berberine, baicalin and geniposide) contained in the extract of HLJDD were assayed with high performance liquid chromatography (HPLC). Type 2 diabetic rats were induced by high fat diet and streptozotocin. Type 2 diabetic rats were treated with HLJDD extract for 30d, while blood glucose and body weight were monitored during the experiment. At the end of experiment, the levels of total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C) and high density lipoprotein cholesterol (HDL-C) were assayed. Intestinal mucosa homogenate was prepared and the activity of pancreatic lipase was analyzed. Moreover, the olive oil loading test (OOLT) was performed and the inhibitory effect of HLJDD extract on the pancreatic lipase in vitro was evaluated. The results showed that, after the treatment of HLJDD extract, the final body weight and the levels of fasting plasma glucose, TC, TG and LDL-C were significantly reduced while the HDL-C level was increased in type 2 diabetic rats. The OOLT showed that HLJDD extract could lower the postprandial plasma TG level of type 2 diabetic rats. The activity of pancreatic lipase in type 2 diabetic rats was decreased after the treatment of HLJDD extract. Moreover, HLJDD extract could inhibit the activity of pancreatic lipase in vitro. In conclusion, the TCM prescription HLJDD possessed potent lipid-modulating effect on type 2 diabetic rats. And HLJDD extract exerted hypolipidemic effects partly via inhibiting the increased activity of intestinal pancreatic lipase in type 2 diabetic rats.

Chung S, Huang JD, Baum L, Senapati S, Li M. Effects of Huanglian-Jie-Du-Tang and its modified formula on the modulation of amyloid-β precursor protein processing in Alzheimer's disease models

Huanglian-Jie-Du-Tang (HLJDT) is a famous traditional Chinese herbal formula that has been widely used clinically to treat cerebral ischemia. Recently, we found that berberine, a major alkaloid compound in HLJDT, reduced amyloid-β (Aβ) accumulation in an Alzheimer’s disease (AD) mouse model. In this study, we compared the effects of HLJDT, four single component herbs of HLJDT (Rhizoma coptidis (RC), Radix scutellariae (RS), Cortex phellodendri (CP) and Fructus gardenia (FG)) and the modified formula of HLJDT (HLJDT-M, which is free of RS) on the regulatory processing of amyloid-β precursor protein (APP) in an in vitro model of AD. Here we show that treatment with HLJDT-M and its components RC, CP, and the main compound berberine on N2a mouse neuroblastoma cells stably expressing human APP with the Swedish mutation (N2a-SwedAPP) significantly decreased the levels of full-length APP, phosphorylated APP at threonine 668, C-terminal fragments of APP, soluble APP (sAPP)-α and sAPPβ-Swedish and reduced the generation of Aβ peptide in the cell lysates of N2a-SwedAPP. HLJDT-M showed more significant APP- and Aβ- reducing effects than berberine, RC or CP treatment alone. In contrast, HLJDT, its component RS and the main active compound of RS, baicalein, strongly increased the levels of all the metabolic products of APP in the cell lysates. The extract from FG, however, did not influence APP modulation. Interestingly, regular treatment of TgCRND8 APP transgenic mice with baicalein exacerbated the amyloid plaque burden, APP metabolism and Aβ production. Taken together, these data provide convincing evidence that HLJDT and baicalein treatment can increase the amyloidogenic metabolism of APP which is at least partly responsible for the baicalein-mediated Aβ plaque increase in the brains of TgCRND8 mice. On the other hand, HLJDT-M significantly decreased all the APP metabolic products including Aβ. Further study of HLJDT-M for therapeutic use in treating AD is warranted.

Huang-Lian-Jie-Du-Decotion induced protective autophagy against the injury of cerebral ischemia/reperfusion via MAPK-mTOR signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Huang-Lian-Jie-Du-Decotion (HLJDD, Hwangryun-Hae-Dok-Decotion in Japan), an ancient antipyretic and detoxifying traditional Chinese medicine formula, was reported to have protective effect on ischemic stroke.

AIM OF THE RESEARCH

To investigate the therapeutic effect of HLJDD on ischemic stroke and explore its mode of action.

MATERIAL AND METHODS

A model of ischemic stroke in the rat was established after transient middle cerebral artery occlusion (MCAO) followed by reperfusion. Rats were assigned randomly to groups of control, sham, transient ischemia/reperfusion (I/R), and three treatment groups by HLJDD at 2.5, 5.0, 10.0mg/kg. The neurological deficit, the cerebral infarct size, morphology abnormality, biochemical parameters were examined, and the levels of relevant proteins were determined by immunoblotting analysis to evaluate the protective effects of HLJDD on ischemic stroke and explore the underlying mechanism.

RESULTS

Compared with I/R group, HLJDD significantly ameliorated neurological deficit and histopathology changes, decreased infarct area, and restored the levels of biochemical indicators including nitric oxide (NO), malondialdehyde (MDA), glutathione (GSH), glutathione disulfide (GSSG), total superoxide dismutase (T-SOD), Cu/Zn-SOD, Mn-SOD and glutathione peroxidase (GSH-PX). HLJDD also notably elevated the levels of microtubule-associated protein 1 light chain 3 (LC3), Beclin-1, and other autophagy related genes (Atgs), promoted the activation of extracellular signal-regulated kinases (ERK), protein kinase B (Akt), 3-phosphoinositide-dependent kinase (PDK1), and inhibited the activation of mammalian target of rapamycin (mTOR), c-Jun N-terminal protein kinases (JNK), p38, phosphatase and tensin homolog (PTEN).

CONCLUSION

HLJDD showed neuroprotective effects on ischemic stroke, at least in part to the induced protective autophagy via the regulation of mitogen-activated protein kinase (MAPK) signals. This Akt-independent protective autophagy is favorable in the treatment of stroke, avoiding unfavorable side-effects associated with the inactivation of Akt. The efficacy of HLJDD on ischemic stroke and its safety warranted by its long-term clinical use in traditional Chinese medicine favored further study to develop HLJDD as an effective therapeutic agent to treat ischemic stroke.

Cytochrome P450 2J2 is protective against global cerebral ischemia in transgenic mice

Cytochrome P450 epoxygenase metabolites of arachidonic acid, EETs, have multiple cardiovascular effects, including reduction of blood pressure, protection against myocardial ischemia-reperfusion injury, and attenuation of endothelial apoptosis. This study investigated the hypothesis that transgenic mice with endothelial overexpression of CYP2J2 (Tie2-CYP2J2-Tr) would be protected against global cerebral ischemia induced by bilateral common carotid artery occlusion (BCCAO) and action mechanisms of EETs on cerebral ischemia in cultures of astrocytes exposed to oxygen-glucose deprivation (OGD). Tie2-CYP2J2-Tr mice had significantly increased CYP2J2 expression, increased 14,15-EET production, increases regional cerebral blood flow (rCBF) and microvascular density, decreased ROS production, decreased brain infarct size and apoptosis after ischemia compared to wild type mice, these were associated with increased activation of the PI3K/AKT and apoptosis-related protein in ischemic brain. Addition of exogenous EETs or CYP2J2 transfection attenuated OGD-induced apoptosis in astrocytes via activation of PI3K/AKT and anti-apoptosis pathways. However, these effects were reduced by pretreatments with inhibitor of the PI3K (LY294002) and 14,15-EET (14,15-EEZE), respectively. These results indicate that CYP2J2 overexpression exerts marked neuroprotective effects against ischemic injury by a mechanism linked to increased level of circulating EETs and increases CBF and reduction of apoptosis.

Relationship between Blood Stasis Syndrome Score and Cardioankle Vascular Index in Stroke Patients

Blood stasis syndrome (BSS) in traditional Asian medicine has been considered to correlate with the extent of atherosclerosis, which can be estimated using the cardioankle vascular index (CAVI). Here, the diagnostic utility of CAVI in predicting BSS was examined. The BSS scores and CAVI were measured in 140 stroke patients and evaluated with respect to stroke risk factors. Receiver operating characteristic (ROC) curve analysis was used to determine the diagnostic accuracy of CAVI for the diagnosis of BSS. The BSS scores correlated significantly with CAVI, age, and systolic blood pressure (SBP). Multiple logistic regression analysis showed that CAVI was a significant associate factor for BSS (OR 1.55, P = 0.032) after adjusting for the age and SBP. The ROC curve showed that CAVI and age provided moderate diagnostic accuracy for BSS (area under the ROC curve (AUC) for CAVI, 0.703, P < 0.001; AUC for age, 0.692, P = 0.001). The AUC of the “CAVI+Age,” which was calculated by combining CAVI with age, showed better accuracy (0.759, P < 0.0001) than those of CAVI or age. The present study suggests that the CAVI combined with age can clinically serve as an objective tool to diagnose BSS in stroke patients.

Effect of keishibukuryogan on endothelial function in patients with at least one component of the diagnostic criteria for metabolic syndrome: a controlled clinical trial with crossover design

We evaluated the effect of keishibukuryogan (KBG; Guizhi-Fuling-Wan), a traditional Japanese (Kampo) formula, on endothelial function assessed by reactive hyperemia peripheral arterial tonometry (Endo-PAT2000) in patients with metabolic syndrome-related factors by controlled clinical trial with crossover design. Ninety-two patients were assigned to group A (first KBG-treatment period, then control period; each lasting 4 weeks, with about one-year interval) or group B (first control, then KBG-treatment). In forty-nine (27, group A; 22, group B) patients completing all tests, the mean value of the natural logarithmic-scaled reactive hyperemia index (L_RHI) increased and those of serum nonesterified fatty acid (NEFA), malondialdehyde, and soluble vascular cell adhesion molecule 1 decreased significantly during the KBG-treatment period, but not during the control period, and 4-week changes of L_RHI, NEFA, and malondialdehyde between the 2 periods showed significance. These results suggest that KBG has beneficial effect on endothelial function in patients with metabolic syndrome-related factors.

Evaluation of oxygen radical absorbance capacity in kampo medicine

Antioxidant capacity of food has come to be shown in terms of oxygen radical absorbance capacity (ORAC) mainly on vegetables or fruit. However, the evaluation of Kampo in terms of ORAC has not yet been accomplished. It is important that such an investigation is also conducted for Kampo medicine. We measured the ORAC value of almost all the available Kampo formulas used in the Japanese National health insurance system and examined the ORAC value both for the daily prescription, and also the crude herb ingredients. The ORAC value of Kampo medicine ranged 4.65–5913 units/day. The ORAC value was high in Kampo formulas including Rhei Rhizoma, and was relatively high in Kampo formulas including anti-inflammatory herbs other than Rhei Rhizoma. The ORAC value was also high in Kampo formulas including crude herbs that have relaxation effects. The ORAC value of a crude herb would seem to not be fixed but be dependent on combination with other crude herbs from the comparison of different herbs added to the basic Kampo medicine. These results suggest variability and complexity of the antioxidant capacity of Kampo medicine within the similar range of food. On the other hand, investigation of the compound changes of various crude herbs with ORAC may lead to the elucidation of the action mechanism of Kampo medicine.

A study of the comparative effects of hawthorn fruit compound and simvastatin on lowering blood lipid levels

This project studied the lowering blood lipids effect in atherosclerotic ApoE-deficient mice. Group A mice (n = 6), fed with a normal diet, served as the negative control. The experimental groups used mice fed with a high cholesterol diet (HCD) for eight weeks, and then selected for inclusion in the study on the basis of high blood lipid levels and the formation of atherosclerotic lesion plaque, which was indicated by an ultrasound biomicroscopy test. Eighteen mice met the selection criteria (atherosclerotic mice with high blood lipid levels) and these were randomly assigned into three groups B, C and D (n = 6). Group B fed with a HCD, served as the positive control. The intervention Group C was fed with HCD and Simvastatin. The intervention Group D was fed with a HCD and Hawthorn fruit compound (HFC includes Hawthorn and Kiwi fruit extract) for eight weeks. The results showed that after feeding on a HCD, Group B had significantly higher blood lipid levels compared to Group A and this confirmed the validity of Group A and Group B controls in this study. The results also showed that compared to Group B, in both Group C and D, there was a significant reduction in triglyceride and in the ratio between low-density lipoprotein cholesterol (LDL-C) and serum cholesterol. Moreover a reduction of LDL-C was evident in Group D, whereas a similar effect did not occur in Group C. The results indicate that HFC can be considered for the treatment of hyperlipidemia and prevention of atherosclerosis.

Long-term baicalin administration ameliorates metabolic disorders and hepatic steatosis in rats given a high-fat diet

AIM

Baicalin, one of the major flavonoids in Scutellaria baicalensis, possesses antioxidant and anti-inflammatory properties. However, the effects of baicalin on metabolic disorders and hepatic steatosis have not been investigated.

METHODS

Body weight was examined in high-fat diet (HFD)-fed rats with or without baicalin treatment. At the end of the experiment, serum biochemical parameters, liver histology and lipid profile were analyzed to assess whether the animals were suffering from metabolic disorders or hepatic steatosis. In the liver, the phosphorylation of AMP activated protein kinase (AMPK) and acetyl-CoA carboxylase (ACC) and the gene expression of some enzymes involved in lipogenesis were examined. The effects of baicalin on the phosphorylation of AMPK and lipid accumulation induced by high glucose in human hepatoma HepG2 cells were also examined.

RESULTS

Baicalin (80 mg/kg) administered ip for 16 weeks suppressed body weight gain in HFD-fed rats. Weight reduction was accompanied by the reduction of visceral fat mass. Baicalin significantly decreased the elevated serum cholesterol, free fatty acid and insulin concentrations caused by the HFD. Baicalin also suppressed systemic inflammation by reducing the serum level of tumor necrosis factor alpha. Baicalin reduced hepatic lipid accumulation, enhanced the phosphorylation of AMPK and ACC and down-regulated genes involved in lipogenesis, including fatty acid synthase and its upstream regulator SREBP-1c. In HepG2 cells, baicalin (5 and 10 micromol/L) increased the phosphorylation of AMPK and decreased lipid accumulation following the addition of high glucose.

CONCLUSION

Our study suggests that baicalin might have beneficial effects on the development of hepatic steatosis and obesity-related disorders by targeting the hepatic AMPK.

Identification of multiple constituents in the traditional Chinese medicine formula GuiZhiFuLing-Wan by HPLC-DAD-MS/MS

GuiZhiFuLing-Wan (GFW) has been used in China for centuries to improve blood stagnation. In this paper, a HPLC-DAD-MS/MS method was established for the efficient and rapid identification of the chemical constituents in extract of GuiZhiFuLing-Wan. Separation was performed on an Alltima C(18) analytical column by gradient elution with CH(3)CN/H(2)O-CH(3)COOH as mobile phase at a flow rate 1.0ml/min. 27 potentially bioactive compounds including monoterpene glycosides, galloyl glucoses, acetophenones, phenylallyl compounds and triterpenoids were identified or tentatively characterized by online ESI/MS/MS and the comparison with literature data and authentic compounds. After the identification, six different brands of GFW commercial products in various dosage forms were evaluated. The results demonstrated that capsule of GFW was superior to the other two dosage forms, honeyed pill and concentrated pill in administration. The points that should be paid more attention during the manufacturing process of GFW were also analyzed. The method can be the basis for the quality control of this commonly used herbal formula.

Evidence-Based Efficacy of Kampo Formulas in a Model of Non Alcoholic Fatty Liver

Data on the efficacy of herbal compounds are often burdened by the lack of appropriate controls or a limited statistical power. Treatments to prevent the progression of non alcoholic fatty liver disease (NAFLD) to steatohepatitis (NASH) remain unsatisfactory. A total of 56 rabbits were arrayed into 7 groups fed with standard rabbit chow (SRC), SRC with 1% cholesterol, or each of the five experimental treatments (Kampo formulas 1% keishibukuryogan [KBG], 1% orengedokuto [OGT], and 1% shosaikoto [SST]; vitamin E [VE]; or pioglitazone [PG]) in a 1% cholesterol SRC. We analyzed changes after 12 weeks in plasma and liver lipid profiles, glucose metabolism, adipocytokines, oxidative stress, and liver fibrosis. Data demonstrated that all five treatments were associated with significant amelioration of lipid profiles, oxidative stress, and liver fibrosis compared to no supplementation. KBG was superior to VE and PG in the reduction of liver total cholesterol ( P < 0.01) and lipid peroxidase levels ( P < 0.05), urinary 8-hydroxy-2′-deoxyguanosine ( P < 0.05), hepatic α-smooth muscle actin positive areas ( P < 0.01) and activated stellate cells ( P < 0.01). In conclusion, there was a statistically significant benefit of Kampo formulas (KBG in particular) on a dietary model of NAFLD/NASH. Future studies need to be directed at the mechanisms in the treatment of NASH.

Effects of keishibukuryogan on vascular function in adjuvant-induced arthritis rats

It is known that rheumatoid arthritis (RA) accelerates atherosclerosis. Further, the soluble form of vascular adhesion molecule-1 (VCAM-1) is known as a predictive marker of atherosclerosis in RA patients. We reported that keishibukuryogan, one of the Kampo formulas, improved articular symptoms and decreased soluble VCAM-1 in patients with RA. In adjuvant-induced arthritis (AIA) rats, an animal model of RA, it is known that endothelial function is injured by inflammation. So, we investigated the effect of keishibukuryogan on endothelial function in AIA rats. Lewis rats were divided into control, AIA control, and AIA with keishibukuryogan groups. The AIA with keishibukuryogan group was fed 3% keishibukuryogan contained in normal chow. On day 25 after injection of Mycobacterium butyricum, endothelium-dependent relaxation by acetylcholine in the AIA control group was suppressed, but it was improved in the AIA with keishibukuryogan group. The contractions by xanthine/xanthine oxidase in both AIA rats increased, but that in keishibukuryogan decreased compared to the AIA control group. Plasma levels of lipid peroxide increased in the AIA control group, but keishibukuryogan decreased these levels. Plasma levels of nitric oxide (NO) increased in both AIA groups. The expressions of endothelial NO synthase, inducible NO synthase and VCAM-1 of thoracic aorta were investigated by western blotting. These expressions increased in the AIA control group, but were restricted in the AIA with keishibukuryogan group. We considered that keishibukuryogan protected the endothelial function of AIA rats mainly by its anti-oxidative effect.

Evolution of medical treatment for endometriosis: back to the roots?

Experimental evidence is accumulating to suggest that medicinal botanicals have anti-inflammatory and pain-alleviating properties and hold promise for treatment of endometriosis. Herein, we present a systematic review of clinical and experimental data on the use of medicinal herbs in the treatment of endometriosis. Although there is a general lack of evidence from clinical studies on the potential efficacy of medicinal herbs for the treatment of endometriosis-associated symptoms, our review highlights the anti-inflammatory and pain-alleviating mechanisms of action of herbal remedies. Medicinal herbs and their active components exhibit cytokine-suppressive, COX-2-inhibiting, antioxidant, sedative and pain-alleviating properties. Each of these mechanisms of action would be predicted to have salutary effects in endometriosis. Better understanding of the mechanisms of action, toxicity and herb-herb and herb-drug interactions permits the optimization of design and execution of complementary alternative medicine trials for endometriosis-associated pain. A potential benefit of herbal therapy is the likelihood of synergistic interactions within individual or combinations of plants. In this sense, phytotherapies may be analogous to nutraceuticals or whole food nutrition. We encourage the development of herbal analogues and establishment of special, simplified registration procedures for certain medicinal products, particularly herbal derivates with a long tradition of safe use.

High-performance liquid chromatographic method for the determination and pharmacokinetic study of wogonoside in rat serum after oral administration of traditional Chinese medicinal preparation Huang-Lian-Jie-Du decoction

A high-performance liquid chromatographic method for the determination of wogonoside in plasma of rats administrated orally with the traditional Chinese medicinal preparation Huang-Lian-Jie-Du decoction was developed. Sample preparation was carried out by protein precipitation with a mixture of acetonitrile and methanol (1:1, v/v). The extracted sample was separated on a Hypersil C(18) (150 x 5 mm i.d., 5 microm) analytical column by linear gradient elution using 0.05% (v/v) phosphoric acid (containing 5 mm sodium dihydrogen phosphate) and acetonitrile as mobile phase at a flow rate of 1.5 mL/min. The eluate was detected using a UV detector at 276 nm. The assay was linear over the range 0.109-7.0 microg/mL (R(2) = 0.9999, n = 5). Mean recovery was determined as 98.39%. Intra- and inter-day precisions (RSD) were < or =7.59%. The limit of quantitation was 0.109 microg/mL. After validation, the HPLC method developed was applied to investigate the preliminary pharmacokinetics of wogonoside in rat after oral administration of Huang-Lian-Jie-Du decoction.

Protective Effects of Guizhi-Fuling-Capsules on Rat Brain Ischemia/Reperfusion Injury

Previous studies revealed that Guizhi-Fuling-Capsules (GZFLC), a traditional Chinese medical (Kampo) formulation composed of five kinds of medicinal plants, Cinnamomum cassia BLUME (Cinnamomi Cortex), Paeonia lactiflora PALL. (Peonies Radix), Paeonia suffruticosa ANDREWS (Moutan Cortex), Prunus persica BATSCH (Persicae Semen), and Poria cocos WOLF (Hoelen), exerts a protective effect against vascular injury and has a protective effect against glutamate- or nitro oxide-mediated neuronal damage. In the present study, the effect of GZFLC in a rat in vivo model of focal cerebral ischemia and reperfusion was investigated. Administration of GZFLC (0.3 and 0.9 g/kg, p.o.) after focal cerebral ischemia significantly decreased brain infarction and water contents in rats subjected to 2-h ischemia followed by 24-h reperfusion from 31.72 +/- 2.49%, 84.76 +/- 1.63% in the model group to 17.31 +/- 3.66%, 82.51 +/- 1.36% and 8.30 +/- 3.73%, 81.35 +/- 1.73%, respectively. Furthermore, analysis of inflammatory cytokines in ischemic brain showed that GZFLC treatment significantly down-regulated expressions of pro-inflammatory cytokines including interleukin (IL)-1beta and tissue necrosis factor-alpha and markedly up-regulated expressions of anti-inflammatory cytokines IL-10 and IL-10R both in mRNA and protein levels. The serum levels of these inflammatory cytokines were also regulated the same way. These results suggested that GZFLC may be beneficial for the treatment of brain ischemia-reperfusion injury partly due to its anti-inflammatory properties.

Rediscovery of natural products using genomic tools

A screening methodology called 'genomic screening' was established to identify natural products that can regulate cellular gene expression. Application of genomic screening to Keishi-bukuryo-gan (KBG), a Japanese herbal medicine formulation, identified a previously unnoticed transcriptional effect by linoleic acid, a known KBG component. The approach opens up a possibility to develop cell-permeable molecular tools for functional genomics research and sets a stage to evaluate the potential of natural products for transcription therapies.

Cinnamaldehyde Induces Endothelium-Dependent and -Independent Vasorelaxant Action on Isolated Rat Aorta

The vasorelaxant effect of cinnamaldehyde, one of the major oil components in Cinnamomi Cortex, was studied using isolated rat aorta. Cinnamaldehyde at final concentrations of 1 microM to 1 mM showed dose-dependent relaxation of the rat aorta contracted by treatment with prostaglandin F2alpha, norepinephrine or KCl. In addition, cinnamaldehyde relaxed prostaglandin F2alpha-precontracted aortic rings with endothelium and without endothelium, with the latter being significantly less sensitive than the former. Relaxation induced by cinnamaldehyde with endothelium was significantly inhibited by NG-nitro-L-arginine methyl ester (L-NAME), while nonselective cyclooxygenase inhibitor (indomethacin), beta-adrenergic receptor blocker (propranolol), an inhibitor of phosphodiesterase (theophylline), a delayed rectifier K+ channel blocker (tetraethyl ammonium chloride), or an ATP-sensitive K+ channel blocker (glibenclamide) did not reduce the relaxation induced by cinnamaldehyde with endothelium treated by L-NAME. Conversely, aorta pretreatment with L-NAME and theophylline increased the relaxation by cinnamaldehyde significantly compared to aorta pretreatment with only L-NAME. Furthermore, cinnamaldehyde significantly inhibited Ca2+-induced contraction. These results suggested that the vasorelaxant effects of cinnamaldehyde were derived from both endothelium-dependent and -independent effects. Endothelium-dependent relaxation is affected by nitric oxide, and one of the mechanisms of endothelium-independent relaxation is thought to be influenced by the blocking of Ca2+ channels.