[Effects of sanguisorba tannins and saponins compatibility on pharmacokinetic parameters of catechin, epicatechin and ziyuglycoside â in rats].

To study the effects of sanguisorba tannins and saponins compatibility at different proportions [tannins-saponins (1∶1) and tannins-saponins(8∶1)] after intragastric administration (50 mg•kg⁻¹) on pharmacokinetic parameters of catechin, epicatechin and ziyuglycoside Ⅰ in rats by using pharmacokinetic techniques and methods. Kinetica 5.0 software was used to calculate the pharmacokinetic parameters. The results showed that the specificity, linearity, recovery rate, precision and stability of the established detection method were in line with the test requirements. When the sanguisorba tannins and eaponins were combined at the rate of 1∶1, Vd and CL of catechin and epicatechin were increased significantly（P<0.05); MRT was significantly shortened(P<0.05); Cmax and AUC were significantly reduced(P<0.05). When the sanguisorba tannins and saponins were combined at the rate of 8∶1, Vd and CL of catechin and epicatechin were significantly reduced(P<0.05); MRT was significantly prolonged(P<0.05); Cmax and AUC were increased significantly(P<0.05). In addition, with the increase in proportion of sanguisorba tannins in the compatibility, Cmax and AUC of ziyuglycoside Ⅰ were increased significantly(P<0.05); Vd and CL were significantly reduced(P<0.05), Tmax was obviously lagging behind, and MRT was also significantly prolonged(P<0.05). In our present study, catechin, epicatechin and ziyuglycoside Ⅰ showed good pharmacokinetic behavior in rats when sanguisorba tannins and saponins were combined at the rate of 8∶1 in compatibility, which could be used as a reference for the proportion in sanguisorba tannins and saponins compatibility.

Review of lignans from 2019 to 2021: Newly reported compounds, diverse activities, structure-activity relationships and clinical applications.

Lignans, with various biological activities, such as antitumor, antioxidant, antibacterial, and antiviral activities, are widely distributed in nature and mainly exist in the xylem of plants. In this paper, we summarized the structures and bioactivities of lignans reported in recent years (2019-2021) from five parts, including (1) a summary and classification of newly reported compounds; (2) the pharmacological activities of lignans; (3) molecular resources and activity distribution; (4) the structure-activity relationships; and (5) the clinical application of lignans. This review covers all undescribed compounds that were reported within the covered period of time and all bioactivity data about previously isolated lignans. The distribution of lignans in different plants and families is visualized, which improves the efficiency of searching for specific molecules. The diverse activities of different types of lignans provide an important reference for the rapid screening of these compounds. Discussion about the structure-activity relationships of lignans provides a direction for the structural modification of skeleton molecules. Combined with the clinical application of such molecules, this work will provide a valuable reference for pharmaceutical chemists.

Characterization, pharmacokinetics and tissue distribution of chlorogenic acid-loaded self-microemulsifying drug delivery system.

The purpose of this study was to develop a self-microemulsifying drug delivery system (SMEDDS) to improve the oral bioavailability of Chlorogenic acid (CA), an important bioactive compound from Lonicerae Japonicae Flos with poor permeability. SMEDDS was prepared and characterized by self-emulsifying rate, morphological observation, droplet size determination, stability, in vitro release, in vivo bioavailability and tissue distribution experiments. Results shown that the SMEDDS of CA has a high self-emulsifying rate (>98%) in the dissolution media, and its microemulsion exhibits small droplet size (16.37nm) and good stability. In vitro release test showed a complete release of CA from SMEDDS in 480min. After oral administration in mice, significantly enhanced bioavailability of CA was achieved through SMEDDS (249.4% relative to the CA suspension). Interestingly, SMEDDS significantly changed the tissue distribution of CA and showed a better targeting property to the kidney (2.79 of the relative intake efficiency). It is suggested that SMEDDS improves the oral bioavailability of CA may mainly through increasing its absorption and slowing the metabolism of absorbed CA via changing its distribution from the liver to the kidney. In conclusion, it is indicated that SMEDDS is a promising carrier for the oral delivery of CA.