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Background: Baicalin, a flavonoid glycoside compound present in Scutellaria baicalensis, has shown a wide spectrum of biological activities, but its liposolubility, water-solubility and mucosal permeability are all very poor, which leads to the low concentration in brain and poor bioavailability by oral or intravenous injective administration., Objective: The primary objective of this study was to formulate the Scutellaria baicalensis extract (SBE) with phospholipid to yield Scutellaria baicalensis extract-phospholipid complex (SBEPC) , and to evaluate its pharmacodynamics in the middle cerebral artery occlusion (MCAO)., Methods: The optimal preparation technology of SBEPC was obtained through single-factor test and central composite design-response surface methodology (CCD-RSM), and was characterized with various analytical techniques including SEM, FT-IR and NMR. The storage conditions of SBEPC were established through stability study and the MCAO rat model was investigated through conducting pharmacodynamic studies to screen the appropriate administration and dose of SBEPC as well as to verify the neuroprotective effect of SBEPC on cerebral ischemia-reperfusion injury., Results: The optimized preparation conditions of SBEPC were summarized as follows: the ratio of phospholipids to drug was 2:1, the drug concentration was 3.5 mg/ml, the reaction temperature was 50 °C, and the entrapment efficiency was over 93.00%. Stability studies have demonstrated that SBEPC should be stored under 40 °C in a dry and ventilated place away from light and below 37% humidity. Furthermore, pharmacodynamic studies have found that, compared with SBE, SBEPC could introduce drugs into the brain and better exert the neuroprotective effect on MCAO rats, and the optimal administration and dose concentration of SBEPC were nasal administration and 40 mg/ml, respectively., Conclusion: These findings demonstrate that SBEPC is successfully prepared by CCD-RSM. SBEPC can enhance drugs' ability to enter the brain and improve the bioavailability of drugs in brain, and can effectively exert the neuroprotective effect on cerebral ischemia-reperfusion injury as compared with SBE., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Background: Cistanche tubulosa is a tonic in traditional Chinese medicines and has a broad spectrum of biological activity, including anti-inflammatory. However, the anti-inflammatory major constituents of C. tubulosa and their underlying mechanisms are still unknown., Objective: The aim of the current study was to explore the separation and structural characterization of lignan glycosides from C. tubulosa (Schenk) Wight., their anti-inflammatory activity and the underlying mechanism., Materials and Methods: Fractionation and isolation of the 85% EtOH extract of C. tubulosa (Schenk) Wight. were carried out and the primary ingredients lignan glycosides (1-6) were structurally characterized. CCK8 methods were used to evaluate the cytotoxic effect of lignan glycosides (1-6). Effects of lignan glycosides (1-6) on NO production in LPS/IFN-γ-induced RAW264.7 macrophages cells were measured using Griess reagent by reaction with nitrite. The mRNA expression levels of iNOS, COX-2, IL-1β, IL-6, TNF-a, and TGF-β treated RAW264.7 cells with various concentrations (0, 25 and 50 μg/ml) of lignan glycosides (1, 4) in the presence of LPS (10 ng/ml) and IFN-γ (20 ng/ml) for 24 h were analyzed by quantitative RT-PCR. Also, the protein expressions of iNOS, COX-2, PI3K, AKT, p-AKT and β -actin were determined using Western blot analysis. A molecular docking study was performed to investigate the interactions between the lignan glycosides and the PI3K using Autodock vina 1.1.2 package., Results: Six lignan glycosides (1-6) were isolated from stems of C. tubulosa. Among them, (+)- pinoresinol-4-O-β-D-glucopyranosyl-(1→6)-β-D-glucopyranoside (5) and eleutheroside E (6) were firstly isolated from C. tubulosa. Of these lignans, 1 and 4 exhibited pronounced inhibitions on NO production with the values of 33.63 ± 4.78 and 39.28 ± 5.52 % at 50 μg/ml, respectively. Additionally, LPS/IFN-γ-induced expression of inducible Nitric Oxide Synthase (iNOS), Cyclooxygenase-2 (COX-2), Interleukin-1β (IL-1β), IL-6, and Tumor Necrosis Factor-a (TNF-a) was significantly suppressed by pre-treatment of 1 and 4 in a dose-dependent manner. While 1 and 4 increased the mRNA levels of anti-inflammatory cytokines (TGF-β). Furthermore, 1 and 4 significantly inhibited the protein levels of PI3K and p-AKT in a dose-dependent manner., Conclusion: Taken together, these results suggest that 1 and 4 play an important role in the attenuation of LPS/IFN-γ-induced inflammatory responses in RAW264.7 cells and that the mechanisms involve down-regulation of the PI3K/AKT pathway., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)