Scutellaria Extract Research Articles

Anti-Arthritic, Anti-Inflammatory, Thrombolytic, Membrane Stabilizing, Antifungal and Cytotoxic Activity of Polyscias scutellaria Leaf Extract: An In-vitro Analysis

The objective of this investigations was to evaluate in Vitro anti-arthritic, anti-inflammatory, thrombolytic, membrane stabilizing, antifungal and cytotoxic activities from the methanolic leaf extract of Polyscias scutellaria. Primary evaluation of methanolic extract of Polyscias scutellaria leaf (MEPSL) was performed via phytochemical screening. Presence of Alkaloids, flavonoids, saponins, glycosides, carbohydrates and reducing sugars were observed by phytochemical screening, among other secondary compounds. Using in vitro methods of protein denaturation, the anti-arthritic and anti-inflammatory properties of MEPSL was investigated. The results showed that the extracts significantly slowed down arthritis and inflammation with the percent inhibition of 94.59% and 86.33% at the conc. of 1000 µg/mL compared to the standard diclofenac sodium (98.19%) and acetyle salicylic acid (98.56%) at same concentration respectively. The thrombolytic activity of the extracts was additionally examined by clotlysis method, and the results showed that the ability to break up blood clots increased with the amount of extract used with the value of 97.32% which is very significant compared to the standard streptokinase which showed clotlysis of 91.304%. MEPSL was also showed action that stabilized membranes by using heat induced hemolysis method, which could be helpful in treating conditions like bleeding and swelling with the percent of protection value of 58.87% when compared to standard diclofenac sodium with the percent of protection value 73.63%. Antifungal action was also seen, which shows that it could be used to treat diseases caused by fungi with the zone of inhibition 7-36 mm varying on the type of fungi. Lastly, in vitro method was used to investigate the extracts' damaging effect on Artemia salina by using shrimp lethality assay. The results showed significant cytotoxicity with the LC50 value of 1.057 µg/mL compared to the standard vincristine sulphate (LC50 value of 0.608 µg/mL). To sum up, it is clear that the phytochemical found in this plant can be used for wide range of drug discovery field due to its potent pharmacological actions.

In Vitro Assessment of Antifungal and Antibiofilm Efficacy of Commercial Mouthwashes against Candida albicans.

Candida albicans is the most critical fungus causing oral mycosis. Many mouthwashes contain antimicrobial substances, including antifungal agents. This study aimed to investigate the in vitro activity of 15 commercial mouthwashes against 12 strains of C. albicans. The minimal inhibitory concentrations (MICs), minimal fungicidal concentrations (MFCs), and anti-biofilm activity were studied. MICs were determined by the micro-dilution method using 96-well plates, and MFCs were determined by culturing MIC suspensions on Sabouraud dextrose agar. Anti-biofilm activity was evaluated using the crystal violet method. The mouthwashes containing octenidine dihydrochloride (OCT; mean MICs 0.09-0.1%), chlorhexidine digluconate (CHX; MIC 0.12%), and CHX with cetylpyridinium chloride (CPC; MIC 0.13%) exhibited the best activity against C. albicans. The active compound antifungal concentrations were 0.5-0.9 µg/mL for OCT products and 1.1-2.4 µg/mL for CHX rinses. For mouthwashes with CHX + CPC, concentrations were 1.56 µg/mL and 0.65 µg/mL, respectively. Products with polyaminopropyl biguanide (polyhexanide, PHMB; MIC 1.89%) or benzalkonium chloride (BAC; MIC 6.38%) also showed good anti-Candida action. In biofilm reduction studies, mouthwashes with OCT demonstrated the most substantial effect (47-51.1%). Products with CHX (32.1-41.7%), PHMB (38.6%), BAC (35.7%), Scutellaria extract (35.6%), and fluorides + essential oils (33.2%) exhibited moderate antibiofilm activity. The paper also provides an overview of the side effects of CHX, CPC, and OCT. Considering the in vitro activity against Candida albicans, it can be inferred that, clinically, mouthwashes containing OCT are likely to offer the highest effectiveness. Meanwhile, products containing CHX, PHMB, or BAC can be considered as promising alternatives.

Green precipitation method using Polyscias scutellaria extract in the synthesis of hydroxyapatite/alginate/copper (II) oxide composites as a drug carrier

Green precipitation method using Polyscias scutellaria extract in the synthesis of hydroxyapatite/alginate/copper (II) oxide composites as a drug carrier

Development of an amoxicillin-radix scutellaria extract formulation and evaluation of its pharmacokinetics in pigs

BackgroundA new antibacterial compound powder of amoxicillin (AMO)/Radix Scutellaria extract (RSE) was developed, and its pharmacokinetics were determined in pigs following oral administration.ResultsThe MIC ranges of AMO against Escherichia coli, Staphylococcus aureus and Streptococcus were 1–8 μg/mL, 0.5–4 μg/mL and 0.5–64 μg/mL, respectively. The MIC ranges of RSE against E. coli, S. aureus, and Streptococcus were greater than 2.5 mg/mL, 0.156–2.5 mg/mL, and greater than 2.5 mg/mL, respectively. For S. aureus, the combined drug susceptibility test showed that AMO and RSE had an additive or synergistic effect. The results of compatibility test, the excipient screening test and the drug quality control test showed that the formulation had stable quality and uniform properties under the test conditions. Two studies were conducted to investigate the pharmacokinetics of the compound product in pigs. First, the pharmacokinetics of the AMO-RSE powder were compared with those of their respective single products. The results showed no significant change in the main pharmacokinetic parameters when either component was removed from the compound formulation; thus, AMO and RSE have no pharmacokinetic interaction in pigs. Second, pigs were orally administered three different doses of AMO-RSE powder. The Cmax and AUC increased proportionally with increasing p.o. dose; thus, the λz, t1/2λ, MRT, and Tmax were unchanged for the doses of 10, 20, and 30 mg/kg AMO and the doses of 5, 10, and 15 mg/kg BCL, showing that AMO/baicalin in AMO-RSE powder showed linear pharmacokinetic characteristics in pigs.ConclusionsThe combined drug sensitivity test of AMO and RSE against S. aureus showed that the combination was additive or synergistic. Pharmacokinetic studies indicated that AMO and BCL do not interfere with each other in pigs when used in a compound formulation. The pharmacokinetic parameters remained unchanged regardless of the dose for p.o. administration, indicating linear pharmacokinetic properties over the tested dose range. The quality of the AMO-RSE powder was good and stable, providing a foundation for its clinical application in veterinary medicine. Further bioavailability, PK/PD and clinical trials are still needed to determine the final dosage regimen.

The Influence of Microwave-Assisted Extraction on the Phenolic Compound Profile and Biological Activities of Extracts from Selected Scutellaria Species.

The aim of the study was to investigate the effects of microwave-assisted extraction (MAE) conditions (microwave power, extraction time, and ethanol concentration) on the efficiency of the extraction of phenolic compounds from selected plant species belonging to the genus Scutellaria (i.e., Scutellaria baicalensis and Scutellaria lateriflora). The extracts from selected Scutellaria species were examined to establish the total phenolic content and the in vitro antioxidant and anti-inflammatory activity. The antioxidant capacity was determined by the ferric reducing antioxidant power (FRAP) and 2,2,1-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging capacity methods. The anti-inflammatory activity was evaluated through the lipoxygenase (LOX) inhibitory assay. The phenolic profile of the extracts was characterized using ultra-high performance liquid chromatography coupled with diode array detection and high-resolution electrospray ionization mass spectrometry (UHPLC-DAD/ESI-HRMS/MS). Depending on the type of solvent and the extraction conditions used, the extracts obtained from selected Scutellaria species showed different total and individual phenolic content, as well as different antioxidant and anti-inflammatory properties. The results showed that all Scutellaria extracts had high total phenolic content and exhibited strong ferric ion reducing power and free radical scavenging capacity and a significant ability to inhibit the LOX activity. In general, the 70% ethanol extracts contained more phenolic compounds, mainly flavones, flavanones, and their derivatives, and showed greater in vitro biological activity than other extracts. The highest levels of phenolic compounds and the strongest antioxidant and anti-inflammatory potential were found in extracts from the roots of S. baicalensis. Optimal extraction conditions for all the plant materials tested were determined as the microwave power of 63 W, extraction time of 10 min, and 70% ethanol as the solvent.

Comparative Study of the Flavonoid Content in Radix Scutellaria from Different Cultivation Areas in China.

Scutellariabaicalensis Georgi, an important perennial herb, is widely distributed and used all over the world. The root of S. baicalensis (Radix Scutellaria) is rich in flavonoids with a variety of bioactive effects and is widely used in clinic. The different geographical and climatic conditions of different cultivated areas of S. baicalensis lead to the differences of the main components in Radix Scutellaria. The main objective of this study was to evaluate the difference of flavonoid content in Radix Scutellaria from different cultivated areas in China. The mobile phase system, elution gradient, detection wavelength, and other chromatographic conditions for high-performance liquid chromatography-diode array detection (HPLC-DAD) determination of 8 flavonoids in Radix Scutellaria were optimized. The contents of flavonoids in 38 samples of Radix Scutellaria collected from seven main genuine cultivated areas were determined, and the correlation between the content, cultivated area, and the biological activities of Radix Scutellaria was compared. The results implied that baicalin, wogonoside, and baicalein were the three main flavonoids with the highest contents in Radix Scutellaria. The content of flavonoids in different cultivated areas was very different, which had significant regionality and was closely related to the natural conditions of various places. The antioxidant and antitumor activities of the extract of Radix Scutellaria were closely related to the content of flavonoids, and high contents of baicalin, wogonoside, and baicalein positively improved biological activities.

Study the interactions between multiple flavonoids and bovine serum albumin by the developed equilibrium dialysis

The therapeutic function of traditional Chinese medicine (TCM) is based on the combination effect of multiple active ingredients. However, the current pharmacological studies mainly focus on the protein binding of the single component from TCM, which is difficult to explain the overall therapeutic mechanism. Thus in this work the equilibrium dialysis method combined with high performance liquid chromatography (HPLC) and ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was developed to study the interactions between multi-components and protein. Firstly, the binding constants of seven different structural types of flavonoids with bovine serum albumin (BSA) were determined. The results showed that the binding affinity of flavones and flavonols with BSA was stronger than that of dihydroflavonoids, and the substitution of glycosides would reduce the binding affinity with BSA. The results of competitive displacement experiment showed that there existed competitive interactions among the four flavonoids (rutin, luteolin, hesperetin and kaempferol). The binding constants of flavonoids to BSA were significantly changed under the condition of multi-components coexistence. Especially, the binding constant of hesperetin to BSA increased from 9.46 × 104 L/mol to 1.49 × 106 L/mol under the coexistence of rutin. The results of fluorescence spectroscopy showed that the reason for competitive binding was that the four flavonoids were mainly bound to the IIA region of BSA. Finally, the method was successfully applied to study the binding of multiple components in Radix Scutellariae (RS) extract with BSA. Five flavonoids in RS extract were identified by UPLC-MS/MS, they had different degrees of binding to BSA, among which oroxylin A had the strongest binding degree. In conclusion, the equilibrium dialysis was reliable and sufficiently accurate for study of the interaction between multi-components or TCM extract and protein, which can provided a theoretical basis for the scientific explanation of the overall treatment mechanism of TCM.

A study of flavonoid composition and antimicrobial activity of Scutellaria altissima L. from different floristic regions of Bulgaria.

Scutellaria extracts and its constituents, especially the characteristic flavonoids such as baicalein and its glycoside baicalin, exhibit significant antimicrobial activity. To perform a comparative analysis of flavonoid composition and antimicrobial activity of extracts obtained from aerial parts and roots of Scutellaria altissima from the regions of Mezek and Bachkovo, Bulgaria. 70% ethanol and aqueous extracts of aerial parts and roots of S. altissima were used. HPLC analysis of S. altissima extracts was performed. Microbiological tests were done on clinical isolates of Streptococcus mitis, Staphylococcus aureus, Escherichia coli, and Candida albicans. Minimal bactericidal and minimal bacteriostatic concentrations of S. altissima extracts were determined by the agar method. The ethanol extracts contain flavonoids approximately twice as much in comparison with the aqueous extracts. The baicalin content in the aerial parts of S. altissima from the region of Mezek is 5 times higher than that in the roots. S. altissima extracts have effective antimicrobial activity against S. mitis only. The minimal bactericidal concentration of ethanol extracts of S. altissima aerial parts and S. altissima roots is 2000µg/ml and 8000µg/ml at 24 hours, respectively. The bactericidal effect of aqueous extracts occurs at 48 hours at minimal bactericidal concentration of S. altissima aerial parts - 2000µg/ml and of S. altissima roots - 6000µg/ml. The finding that extracts of Bulgarian S. altissima possess effective antimicrobial properties against S. mitis suggests that it can be used as a potential source for the development of natural antimicrobial agents to suppress oral pathogens and prevent some oral infections.

Lactogenic effect of Polyscias scutellaria extract to maintain postpartum prolactin and oxytocin in lactating rats

BackgroundHypogalactia remains a challenge for mother to complete exclusive breastfeeding. Shield aralia (Polysicias scutellaria) has been used by Indonesian society to increase breast milk production. ObjectiveThis study aimed to elucidate the novel galactopoietic effect of P. scutellaria extract (PSE) in lactating rats for three weeks. Materials and methodsPSE were assayed for total phenolic content (TPC), total flavonoid content (TFC), and antioxidant capacity. The secondary metabolites of PSE were determined by liquid chromatography-high-resolution mass spectrometry (LC-HRMS). After parturition, dams were randomly divided into four groups: lactating rats (LR) + distilled water (LRO), LR + Asifit, and LR + PSE at doses of 250 and 500 mg/kg body weight (BW). Virgin rats served as the control group. The treatments were given for 14 days. ResultsThere were no significant differences (p > 0.05) in TPC, TFC, and antioxidant capacity among the three solvents. LC-HRMS revealed 22 compounds greater than 70 of the best-match, which were categorised as flavonoids, terpenoids, phenolic acids, and lignan. PSE increased the weight gain and survival rate of pups from our 3-week observation. Serum Prl was significantly higher (p < 0.05) in lactating rats treated with PSE 250 mg/kg BW at the first and third weeks than in the LRO group. Oxt serum was significantly higher (p < 0.05) in lactating rats treated with PSE (500 mg/kg BW) in the first and second weeks than in the LRO group. ConclusionPSE-rich polyphenols are promising galactopoietics by orchestrating Prl and Oxt and reducing the mortality of pups.

The effect of Wogonoside on the expression of TGF-β1/Smad3 in Mycoplasma pneumoniae pneumonia

Screening active compounds from complex herbal extracts is an important part of the drug mechanism research. The present study describes the establishment and application of a sensitive, convenient and efficient method for screening active ingredients targeting pulmonary fibrosis factor TGF-β1 from Radix Scutellariae extracts based on the surface plasmon resonance (SPR) biosensors. Previous studies have proved that Qin bai qing fei pellet (Qin bai) can inhibit the expression of TGF-β1 in Mycoplasma pneumoniae pneumonia (MPP). Radix Scutellariae is the main component of Qin bai. However, the mechanism of Radix Scutellariae inhibiting TGF-β1 expression remains unexplained. The study investigated the active compound in Radix Scutellariae which was bound with TGF-β1 by SPR and UPLC-Q-TOF-MS techonology. As a result, Radix Scutellariae extracts showed a good combination with the TGF-β1 in vitro. Wogonoside was identified as a bioactive ingredient by UPLC-Q-TOF-MS. The affinity constant of Wogonoside to TGF-β1 was determined by SPR affinity analysis (KD=21.7 μm). Pharmacology assays revealed that Wogonoside strongly inhibited the expression of TGF-β1 and Smad3 in A549 cells infected by Mycoplasma pneumoniae(M.pneumoniae). Wogonoside prevented Mycoplasma pneumoniae infection by inhibiting the expression of TGF-β1, which might be one of the mechanisms for the anti-MPP properties of Qin bai. These results provided a foundation to further explore the mechanisms of Qin bai.

Study on HPLC-characteristic chromatogram for evaluation of quality of Scutellaria Extract and influencing factors of preparations

This work was carried out to establish and validate the specific characteristic chromatography of Scutellaria Extract and evaluate the quality of commercial Scutellaria Extract and optimize production process parameters. Scutellaria Extract and formulation samples collected from different manufacturers were analyzed using HPLC-characteristic chromatogram. The HPLC characteristic peaks were considered to be the index for the parameters optimization in preparations of Scutellaria Extract. The chemical pattern recognization was applied for the analysis of characteristic peak data. The established characteristic fingerprint method possessed a good precision, repeatability, and stability. Ten common characteristic peaks were determined and identified in the specific chromatogram of 31 batches of Scutellaria Extract and 4 batches of formulation. The process parameters influenced the characteristic peaks area significantly. The similarity analysis results showed that after removing baicalin peak, the similarity of the characteristic chromatography of 9 samples were less than 0.90, indicating that the quality of commercial Scutellaria Extract was inconsistent. Non-parametric test result showed that the relative peaks area of the number 4, 6, 7 characteristic peaks had significant differences(P&lt;0.05), indicating the differences of the Scutellaria Extract quality were mainly reflected in the characteristic peaks 4, 6 and 7(norwogonin-7-O-glucuronide, oroxylin A-7-O-glucuronide, wogonoside, respectively). The cluster analysis accurately classified 31 extract samples and 4 formulation samples into five categories based on 10 characteristic peaks. The quality of Scutellaria Extracts was comprehensively evaluated and ranked by PCA. The result showed that the higher content of baicalin, the score value of quality(F value) was lower, and the quality of the Scutellaria Extract should be evaluated by multi-components instead of a single baicalin component. The optimized characteristic peaks method is stable and reliable. It is advantageous for the extract and formulations integrative quality control by combining the chemical pattern recognization.

High dose of baicalin or baicalein can reduce tight junction integrity by partly targeting the first PDZ domain of zonula occludens-1 (ZO-1)

The tight junction (TJ) is the apical-most intercellular junction complex, serving as a biological barrier of intercellular spaces between epithelial cells. The TJ's integrity is maintained by a key protein–protein interaction between C-terminal motifs of claudins (CLDs) and the postsynaptic density 95 (PSD-95)/discs large/zonula occludens 1 (ZO-1; PDZ) domains of ZO-1. Weak but direct interaction of baicalin and its aglycon, baicalein—which are pharmacologically active components of Chinese skullcap (Radix scutellariae)—with ZO-1(PDZ1) have been observed in NMR experiments. Next, we observed TJ-mitigating activity of these flavonoids against Madin-Darby canine kidney (MDCK) II cells with the downregulation of subcellular localization of CLD-2 at TJs. Meanwhile, baicalein—but not baicalin—induced a slender morphological change of MDCK cells' shape from their normal cobblestone-like shapes. Since baicalin and baicalein did not induce a localization change of occludin (OCLN), a “partial” epithelial–mesenchymal transition (EMT) induced by these flavonoids was considered. SB431542, an ALK-5 inhibitor, reversed the CLD-2 downregulation of both baicalin and baicalein, while SB431542 did not reverse the slender morphology. In contrast, the MEK/ERK inhibitor U0126 reversed the slender shape change. Thus, in addition to inhibition of the ZO-1–CLD interaction, activation of both transforming growth factor-β (TGF-β) and MEK/ERK signaling pathways have been suggested to be involved in TJ reduction by these flavonoids. Finally, we demonstrated that baicalin enhanced the permeability of fluorescence-labeled insulin via the paracellular pathway of the Caco-2 cell layer. We propose that baicalin, baicalein, and Radix scutellariae extract are useful as drug absorption enhancers.

ANTIBACTERIAL ACTIVITY OF POLYSCIAS SCUTELLARIA FOSBERG AGAINST ACINETOBACTER SP.

Objective: Polyscias scutellaria Fosberg as one of the indigenous plants from Indonesia has been used as traditional medicines for several ailments, such as reduce body odor. However, there is no scientific research to verify this property. This study aimed to evaluate the antibacterial activity of P. scutellaria Fosberg against bacteria that cause body odor.Methods: Since body odor is caused by activities of bacteria that live in the armpits, bacteria from human armpit were isolated and identified as Acinetobacter sp. The bacteria have the potential to be pathogenic and resistant to common antibiotics. P. scutellaria was extracted using different solvents, i.e., hexane, ethyl acetate, and methanol. Using these extracts, the antibacterial activity of P. scutellaria against Acinetobacter sp. was tested through well diffusion and colony-forming unit methods.Results: Hexane and ethyl acetate fractions of P. scutellaria extract showed strong antibacterial activities against Acinetobacter sp., while methanol fraction did not exhibit any antibacterial activity against these bacteria.Conclusion: P. scutellaria extract has the potential to be used as an antibacterial agent against Acinetobacter sp. on human armpit.

ANTIBACTERIAL ACTIVITY OF POLYSCIAS SCUTELLARIA FOSBERG AGAINST ACINETOBACTER SP.

Objective: Polyscias scutellaria Fosberg as one of the indigenous plants from Indonesia has been used as traditional medicines for several ailments, such as reduce body odor. However, there is no scientific research to verify this property. This study aimed to evaluate the antibacterial activity of P. scutellaria Fosberg against bacteria that cause body odor.Methods: Since body odor is caused by activities of bacteria that live in the armpits, bacteria from human armpit were isolated and identified as Acinetobacter sp. The bacteria have the potential to be pathogenic and resistant to common antibiotics. P. scutellaria was extracted using different solvents, i.e., hexane, ethyl acetate, and methanol. Using these extracts, the antibacterial activity of P. scutellaria against Acinetobacter sp. was tested through well diffusion and colony-forming unit methods.Results: Hexane and ethyl acetate fractions of P. scutellaria extract showed strong antibacterial activities against Acinetobacter sp., while methanol fraction did not exhibit any antibacterial activity against these bacteria.Conclusion: P. scutellaria extract has the potential to be used as an antibacterial agent against Acinetobacter sp. on human armpit.

Screening anaphylactoid components of Shuang Huang Lian Injection by analyzing spectrum-effect relationships coupled with UPLC-TOF-MS.

Shuang Huang Lian Injection (SHLI) has been used in China for over 30 years as an effective and widely used Chinese herbal prescription to treat acute respiratory infectious. SHLI has, however, caused many severe anaphylactoid reactions. It is important to identify the potential anaphylactoid components of SHLI. Spectrum-effect relationships were used to explore potentially anaphylactoid components. Based on the original herbal formula, honeysuckle, Fructus Forsythiae and Radix Scutellariae extracts were prepared and combined in appropriate proportions. The preparations were then injected into the caudal vein of rats to obtain in vivo serum samples for pharmacological evaluation and fingerprint analysis. The release rate of β-hexosaminidase from RBL-2H3 cells and plasma histamine level was used as the pharmacological index. Chromatographic fingerprint analysis identified 22 common peaks. Regression analysis and correlation analysis were used to calculate the relationships between the peaks and the pharmacological effects and identified peaks 5, 6, 11, 12 and 17 as likely anaphylactoid agents. The correlated peaks were identified by comparing the fingerprints with in vitro samples and reference standard samples and the structure was identified by UPLC-TOF-MS. This study established a prospective method to clarify the anaphylactoid components in SHLI, which would provide guidances for screening anaphylactoid components in other traditional Chinese medicine injections.

Evaluation of antioxidant activity of extracts from the roots and shoots of Scutellaria alpina L. and S. altissima L. in selected blood cells.

It is widely known that reactive oxygen species (ROS) can cause oxidative damage in cells and have been linked to the pathogenesis of oxidative diseases, such as atherosclerosis, ischemia, neurodegenerative disease, diabetes, or cancer. Recently, much attention has been focused on preventive strategies for oxidative stress and related diseases. Plants represent a source of bioactive compounds whose antioxidant activity may be useful in protecting against pro-oxidative reactions. The study determines the in vitro biological activity of the ethanolic extracts from the shoots and roots of Scutellaria species (S. altissima and S. alpina) in selected blood cells (blood platelets and lymphocytes). Platelet activity, both resting and after thrombin stimulation, was used to indicate the ability of the plant extracts to inhibit the production of superoxide anion radicals (O2 •-) and platelet lipid peroxidation. The generation of superoxide anion radicals was measured by cytochrome c reduction. Lipid peroxidation in blood platelets was measured by the level of thiobarbituric acid reactive substances (TBARS). The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) colorimetric assay was used to determine the protective effect of Scutellaria extracts on lymphocyte cells against oxidative damage induced by hydroxyl radicals. Extracts (5-50 μg/mL) containing phenolic compounds from both Scutellaria species distinctly reduced nonenzymatic lipid peroxidation and arachidonic acid metabolism by blood platelets in vitro. When given at the tested concentration, the extracts reduced the generation of O2 •- in resting blood platelets and platelets activated by thrombin in vitro. All Scutellaria extracts (10 μg/mL) containing phenolic compounds also protected human lymphocytes against oxidative stress induced by hydrogen peroxide (H2O2). The present study suggests that the natural extracts from S. altissima and S. alpina have antioxidant properties and, therefore, may be beneficial in the prevention of diseases in which blood platelets and lymphocytes are involved, i.e., cancer or inflammatory and infective diseases.

Effect of type 2 diabetes mellitus on flavonoid pharmacokinetics and tissue distribution after oral administration of Radix Scutellaria extract in rats

Radix Scutellaria is widely applied to the treatment of diabetes mellitus in China. Its main bioactive constituents contain baicalin, wogonoside, oroxyloside, and their aglycones. To investigate the effect of type 2 diabetes mellitus on both pharmacokinetics and tissue distribution of these flavonoid compounds, the six flavonoids in plasma and tissues from the normal and type 2 diabetic rats after oral administration of Radix Scutellaria extract were simultaneously measured by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method. The results showed that baicalin, wogonoside, and oroxyloside had higher Cmax and AUC values (P < 0.05) in type 2 diabetic rats than that in normal rats and the tissue-distribution behaviors of the six flavonoid compounds in hearts, livers, spleens, lungs, kidneys, brains, pancreas, fat and muscle of the type 2 diabetic rats showed obviously differences from the normal rats (P < 0.05). In conclusion, the differences in the pharmacokinetics of oroxyloside and tissue distribution of the six flavanoids in Radix Scutellaria extract between diabetic and normal rats were found for the first time. The results from the present study provided a crucial basis for a better understanding of in vivo anti-diabetic mechanism of action of the six flavonoids from Radix Scutellaria.

Systematic study on metabolism and activity evaluation of Radix Scutellaria extract in rat plasma using UHPLC with quadrupole time-of-flight mass spectrometry and microdialysis intensity-fading mass spectrometry.

Radix Scutellaria is a widely used traditional Chinese medicine in the treatment of various diseases. However, the activities of the absorbed components and metabolites of its main flavones in rat plasma need further investigation. In this study, a systematic method based on ultra-high performance liquid chromatography with quadruple time-of-flight mass spectrometry was developed to speculate the absorbed components and metabolites of the main flavonoids in Radix Scutellaria extract in rat plasma sample after oral administration of the extract. Twelve compounds, including four prototype components and eight metabolites, were confirmed in drug-containing plasma. In these metabolites, five were originally detected in rat plasma. The possible metabolic pathways of these polyhydroxy flavones in vivo were described and clarified. Microdialysis with intensity-fading mass spectrometry was originally employed to investigate the binding affinities of the absorbed components and metabolites with α-glucosidase. The order of their binding affinities was P4>P3>P2>P1≥M5>M3>M1. The research result is helpful to deepen the understanding of the absorbed components and metabolic pathways of main flavones from Radix Scutellaria, and provide a new approach to screen potential inhibitors from in vivo components originated from Chinese herb.

The Influence of Compatibility of Rhubarb and Radix Scutellariae on the Pharmacokinetics of Anthraquinones and Flavonoids in Rat Plasma.

Rhubarb-Radix scutellariae is a classic herb pair, which is commonly used to clear away heat and toxin in clinic. The aim of this study was to investigate the influence of compatibility of Rhubarb and Radix scutellariae on the pharmacokinetic behaviors of anthraquinones and flavonoids in rat plasma. Eighteen rats were randomly divided into three groups, and were orally administered Rhubarb and/or Radix scutellariae extracts. A sensitive and rapid UPLC-MS/MS method was developed and validated to determine the concentrations of baicalin, baicalein, wogonside, wogonin, rhein, and emodin in rat plasma. The concentrations of phase II conjugates of flavonoid aglycones and anthraquinone aglycones were also determined after hydrolyzing the plasma with sulfatase. Compared with administration of Radix scutellariae alone, co-administration of Rhubarb significantly decreased the first maximum plasma concentration (C max1) of baicalin, wogonside, and the phase II conjugates of baicalein, wogonin to 46.40, 61.27, 41.49, and 20.50%, respectively. The area under the plasma concentration-time curve from time zero to infinity (AUC0-∞) was significantly decreased from 82.60±20.22 to 51.91±7.46μM·h for rhein and 276.83±98.02 to 175.42±86.82μM·h for the phase II conjugates of wogonin after compatibility. The time to reach the first maximum plasma concentration (T max1) of anthraquinones was shortened and the second peak of anthraquinones disappeared after compatibility. Compatibility of Rhubarb and Radix scutellariae can significantly affect the pharmacokinetic behaviors of characteristic constituents of the two herbs. The cause of these pharmacokinetic differences was further discussed combined with the in vivo ADME (absorption, disposition, metabolism, and excretion) processes of anthraquinones and flavonoids.

Enhancement of solubility and dissolution rate of baicalein, wogonin and oroxylin A extracted from Radix scutellariae

Baicalein, wogonin, and oroxylin A are three major hydrophobic components in the extract of Radix scutellariae with wide spectrum of pharmacological applications. The purpose of this study was to enhance the solubility, dissolution rate and stability of baicalein, wogonin and oroxylin A by solid dispersion (SD) technique. SD of the extract with various polymers was prepared to select the best carrier. Solubility study, chemical stability study and dissolution study were performed to characterize the SD. The solubility of all three components, after forming solid dispersion with povidone K-30 (PVP K-30) was significantly increased in pH 6.8 medium at room temperature. Stability study conducted for 80days elucidated that the SD in powder state was fairly stable without the aid of Vitamin C (VC). VC was required as antioxidant to impart stability to baicalein in aqueous medium. The dissolution test of the SD of three components, admixed with VC at the weight ratio of 1:6 (Radix scutellariae extract: VC, w/w) exhibited faster dissolution rate with 100% release of all components. Pharmacokinetic study of baicalein solid dispersion revealed that AUC and Cmax significantly increased by solid dispersion preparation. Thus, the current developed method, being simple, economical and effective, can be useful for the production of soluble dosage forms of the extract of Radix scutellariae in commercial scale.