Scutellariae Radix Extract Research Articles

Effect ofScutellariae Radixextract on experimental dextran-sulfate sodium-induced colitis in rats

To investigate the effect of Scutellariae Radix extract (SRE) on ulcerative colitis (UC) in rats induced by dextran-sulfate sodium (DSS). Colitis was induced in male Sprague-Dawley (SD) rats (170-180 g) by 4% dextran sulfate sodium (DSS, wt/v; MW 54000) in drinking water for 8 d. The treated rats received 4% DSS and SRE orally (100 mg/kg per day). Control rats received either tap water or SRE only. Macroscopic assessment which included body weight changes, fecal occult blood and stool consistency were determined daily. At the appointed time, the rats were sacrificed and the entire colons were removed. The colon length and the myeloperoxidase (MPO) activity were measured. The severity of colitis was graded by morphological and histological assessments. The ion transport activity of the colonic mucosa was assessed by electrophysiological technique. Rats treated with oral administration of 4% DSS regularly developed clinical and macroscopic signs of colitis. Treatment with SRE relieved the symptoms, including the reduction in body weight, shortening and ulceration of the colon. Administration of SRE also significantly reduced the histological damage induced by DSS. Moreover, the I(SC) responses of the colonic mucosa to forskolin were suppressed after the induction of colitis. The stimulated ion transport activity of DSS-rats treated with SRE displayed significant improvement in the secretory responsiveness. SRE was effective in treating acute DSS-induced ulcerative colitis, as gauged by reduced clinical disease, improved macroscopic and histological damage scores, and enhanced recovery of normal colonic secretory function.

알코올 섭취한 생쥐에서 황금(黃芩) 열수추출물이 생쥐의 면역기능에 미치는 영향

High fat diet and chronic alcohol consumption cause hyperlipidemia, steatohepatitis and in some cases, cirrhosis. But the detailed mechanisms are not known. Scutellariae Radix (SR) has been known to have hepatoprotective effects. The aim of this study was, therefore, to determine whether SR water extract (100 mg/kg) could affect immune function in mice abused by long-term alcohol consumption (feed 25% ethanol in water for 1 month, ad libitum) with high fat diet (40% fat of total calorie). Mice received either a regular diet (RD, AIN 93) or a high fat diet (HD); high fat diet group were divided into ethanol group (HED) or ethanol with SR water extract group (HEDS). Food consumption was measured daily and body weights recorded weekly throughout the experiment. Immunological parameters (Ig A, Ig E, TNF-, IFN-, IL-) were measured from the serum and the supernatant of spleen lymphocytes from the all groups. The concentration of serum Ig A, Ig E and cytokines were significantly higher in the alcohol consumed groups. Also the concentration of supernatant of spleen lymphocytes, Ig A, Ig E, cytokines were significantly higher in the ethanol consumption groups. Otherwise, HEDS group were significantly lower than HED group. These results suggest that SR water extract may improve the haptic immune function in mice fed high fat diet with alcohol.

Antibaterial effect of Scutellariae Radix on wild type and mutants of E. coli

Inorganic polyphosphate(poly P)is having been found in all microbes, fungi, plants and animals and Human. In E. coli, an enzyme responsible for polyP synthesis is the polyphosphate kinase(ppk), exopolyphospatase(ppx), which hydrolysed the terminal residues of polyP, was discovered at same operon. Natural herbal extract of Scutellariae Radix(Scutellaria baicalensis George) have been used as antibacterial substance against infected bacteria. Scutellariae Radix extract showed remarkable antimicrobial activity against S. typhimurium, but little attention has been paid to the selective antibacterial activity against pathogenic and nonpathogenic bacteria. This study suggests the possible mechanism(s) of Scutellariae Radix for the selectable antibacterial activities in terms of the relationship between ppk and other relating regulatory genes(sspA and hns)on E.coli. Wild type and ppk mutants strains of E. coli were grown up to 5 mg/ml of Scutellariae Radix containing media. It shows significant differences between deletion mutants and wild type strains on treatment of Scutellariae Radix. Additionally, the results showed not only increased growth rate but also the regulation of gene expression on sspA and hns. Dependent on activities of ppk, the transcriptional activities of sspA and hns altered significantly. So, it suggests that Scutellariae Radix stimulate the transcription(s) either directly or indirectly to ppk and other ppk-relating genes.

Determination of Baicalin by High Performance Liquid Chromatography Coupling with Flow Injection Chemiluminescence Detection

A new method for the determination of baicalin in Scutellariae Radix extract and its preparations by high performance liquid chromatography (HPLC) coupling with flow injection chemiluminescence detection (FIA-CL) has been developed. The method was based on the chemiluminescence reaction of potassium permanganate with baicalin in nitric acid medium; the CL intensity can be enhanced by formaldehyde. In this study, the conditions of chemiluminescence and chromatography were examined, and the schematic diagram of the HPLC-FIA-CL analyzer was optimized. The analytes were separated on Hypersil RP-C18 columns (100 × 4.6 mm, I.D., 5 μm) by equality elution with 47:53 (v/v) methanol-0.3% phosphoric acid as a mobile phase at a flow rate of 0.8 mL·min−1 and a column temperature of 40 °C. Under the optimum condition, the CL intensity was proportional to the concentration of baicalin over the range of 4.10 × 10−7 ˜ 6.15 × 10−5mol·L−1. The limit of detection (S/N = 3) was 2.79 × 10−7mol·L−1 with the relative standard deviation 2.5% (Cs = 6.15 × 10−6 mol·L−1, n = 5). The method has been applied to the determination of baicalin in Scutellariae Radix extract and its preparations, and satisfactory results were obtained.

Kinetic difference of baicalin in rat blood and cerebral nuclei after intravenous administration of Scutellariae Radix extract

Scutellariae Radix, the dried root of Scutellaria baicalensis Georgi (Labiatae), was a commonly used traditional Chinese medicine in clinical practice. Baicalin was one of the effective ingredients enriched in Scutellariae Radix. Recent studies revealed baicalin or Scutellariae Radix extract exhibited various pharmacological activities on cerebral functions. In the present study the pharmacokinetic process of baicalin in normal rat blood and cerebral nuclei (cortex, hippocampus, striatum, thalamus and brain stem) was investigated with a newly established reverse-phase HPLC method after intravenous administration of baicalin-enriched Scutellariae Radix extract prepared according to the special protocol. The pharmacokinetic parameters were calculated by the pharmacokinetic program 3P97 and the regulations of baicalin in blood and cerebral nuclei were comparatively analyzed. The results indicated that the distribution of baicalin into brain was a subsequent process and baicalin tends to accumulate in the striatum, thalamus and hippocampus with the exhibition of large area under the concentration–time curve and mean residence time values ( p < 0.05). All these pharmacokinetic data of baicalin in blood and cerebral nuclei would be useful to the dosage regime design when baicalin, Scutellariae Radix extract or the prescriptions containing Scutellariae Radix as the main ingredient are prescribed.

Determination of Baicalin in Rat Hippocampus by RP-LC After Intravenous Administration of Flavonoids from Scutellariae Radix

A rapid and sensitive method to assay baicalin in rat hippocampus was applied using a simple liquid-liquid extraction technique followed by high-performance liquid chromatography. Baicalin and the internal standard, 4-nitro-benzoic acid, were extracted twice from the homogenized solution with acetonitrile and after centrifugation the combined extracts were evaporated. To the remaining residue 0.1 mL of methanol were added to obtain the sample solution. A 10 μL volume of sample solution was injected onto HPLC for analysis carried out on a Zorbax SB-C18 column using a mobile phase of methanol–water-H3PO4 (45:55:0.2, v/v/v, pH 3.0) at 277 nm with a UV detector. The calibration curve for baicalin was linear over the concentration range of 0.05–1.6 μg mg−1 in hippocampus. Recoveries were reasonable for routine analyses (>88%) and the LOD and LOQ ranged from 0.006 to 0.009 μg mg−1 and 0.015 to 0.035 μg mg−1, respectively. The coefficient of variation of the assay precision was less than 5.9%, and the accuracy exceeded 98%. The method was applied to determine the time course of baicalin in rat hippocampus, following the intravenously administration of flavonoids from Scutellariae Radix extract at 90 mg kg−1 of baicalin to a male Wistar rat. This method provides a very simple, sensitive, and accurate way to determine baicalin concentrations in rat hippocampus.

Effects of Scutellariae Radix Extract and its Components (Baicalein, Baicalin, and Wogonin) on the Experimental Elevation of Aqueous Flare in Pigmented Rabbits

Purpose: To evaluate the possible inhibitory effects of hot water extract of Scutellariae radix and its major components (baicalein, baicalin, and wogonin) on experimental elevation of aqueous flare in pigmented rabbits. Methods: To produce aqueous flare elevation in rabbits, prostaglandin E 2 (PGE 2), 25 μg/mL, was applied to the cornea with the use of a glass cylinder, or lipopolysaccharides (LPS), 0.5 μg/kg, were injected into an ear vein. Animals were pretreated by the oral administration of 150 g/day of food containing 0.02%, 0.07%, or 0.2% (w/w) extract of Scutellariae radix for 5 days, or by intravenous injection of baicalein, baicalin, or wogonin, 60 μg/kg or 600 μg/kg, 30 minutes before experimental uveitis was induced. Aqueous flare was measured with a laser flare-cell meter. Aqueous flare intensity was expressed as the area under the curve (AUC) in arbitrary units. Results: The AUC of PGE 2- and LPS-induced aqueous flare elevation was 1,343 and 5,066 arbitrary units, respectively. Pretreatment by oral administration of 0.07% or 0.2% extract of Scutellariae radix did not inhibit PGE 2-induced aqueous flare elevation (AUC: 1,252 and 1,210, respectively), but it did inhibit LPS-induced aqueous flare elevation (AUC: 2,248 and 1,973, respectively). Pretreatment by intravenous injection of 600 μg/kg of baicalein, baicalin, or wogonin inhibited LPS-induced aqueous flare elevation (AUC: 2,289, 2,163, and 1,509, respectively). Pretreatment with 60 μg/kg of wogonin also inhibited LPS-induced aqueous flare elevation (AUC: 1,980). Conclusion: Hot water extract of Scutellariae radix may have an inhibitory effect on experimental anterior uveitis induced by LPS in pigmented rabbits.

Anticonvulsant effect of water extract of Scutellariae radix in mice

Since a previous study indicated that the water extract of Scutellariae radix (SR) had high affinity for the benzodiazepine (BDZ) binding site of GABA A receptors, the present study examined whether SR water extract has an anticonvulsant effect in vivo and an enhancing effect on γ-amino- n-butyric acid (GABA)-stimulated uptake of 36Cl − in cortex preparation in vitro in mice. The results showed that SR water extract had little effect on pentylenetetrazol (PTZ, 85 mg/kg, s.c.)-induced clonic seizures but significantly inhibited maximal electroshock-induced tonic seizures with an ED 50 of 3.6 g/kg. The BDZ agonist chlordiazepoxide (10 mg/kg, i.p.) had anticonvulsant activity on both types of seizures. In 36Cl − uptake assay, SR water extract (1–500 μg/ml) had no significant effect on 25 μM GABA-stimulated 36Cl − uptake, whereas chlordiazepoxide (10 μM) increased the 36Cl − uptake to 125% of control. Therefore, the present results showed for the first time that SR water extract had anticonvulsant activity against maximal electroshock-induced tonic seizures, and suggested that this anticonvulsant effect might be not via the activation of the BDZ binding site of GABA A receptors, but probably via the prevention of seizure spread.

Induction of quinone reductase by a methanol extract of Scutellaria baicalensis and its flavonoids in murine Hepa 1c1c7 cells.

The effect of extracts of scutellariae radix (Scutellaria baicalensis Georgi) and its flavonoids, baicalin, baicalein and wogonin, on induction of quinone reductase (QR) in the Hepa 1c1c7 murine hepatoma cell line was examined. A significant and dose-dependent induction of QR activity was observed in the methanol extract of scutellariae radix and baicalin. HPCL analysis showed that baicalin was contained as a main component in the methanol extract of scutellariae radix, indicating that baicalin may be the major active principle of QR induction mediated by scutellariae radix extract. To elucidate the mechanism of baicalin-mediated induction of QR enzyme activity, the effect on QR mRNA levels in Hepa 1c1c7 cell cultures was investigated. Using reverse transcriptase-polymerase chain reaction techniques, time- and dose-dependent induction of QR mRNA levels by baicalin were demonstrated in Hepa 1c1c7 cells. On the basis of these results, the scutellariae radix extract or baicalin can be regarded as a readily available, promising, novel cancer chemopreventive agent.

Inhibitory effect of Coptidis Rhizoma and Scutellariae Radix on azoxymethane-induced aberrant crypt foci formation in rat colon.

This study was conducted to obtain effective cancer chemopreventive agents with low toxicity from medicinal herbs. The effect of aqueous extracts from 9 medicinal herbs with antiinflammatory effect were examined on the formation of azoxymethane (AOM)-induced aberrant crypt foci (ACF), putative preneoplastic lesions of the colon. Male F344 rats were treated with 15 mg/kg body weight of AOM once a week for two weeks. Herbal extract consisting of 2% of the diet was administered from 1 d prior to the first carcinogen treatment. The number of AOM-induced ACF per colon was counted at 4 week. Extracts of Coptidis Rhizoma and Scutellariae Radix significantly inhibited AOM-induced ACF formation. The number of ACF was decreased to 54% and 78% of that of the control by 2% Coptidis Rhizoma and Scutellariae Radix extract in the diet, respectively. Berberine and Baicalin, major ingredients of Coptidis Rhizoma and Scutellariae Radix, inhibited ACF formation at a dose equivalent to the amount in each herbal extract. Therefore, to investigate the mechanisms of action of berberine and baicalein which is the active substances of orally administered baicalin, their effects on cyclooxygenase 1 and 2 activities were studied. Berberine was found to inhibit cyclooxygenase 2 activity without inhibition of cyclooxygenase 1 activity, and baicalein inhibited cyclooxygenase 1 activity. Thus, Coptidis Rhizoma and Scutellariae Radix suppressed experimental colon carcinogenesis, and their chemopreventive effects were explained from the inhibition of berberine on cyclooxygenase 2 activity and baicalein on cyclooxygenase 1 activity.