Therapeutic effect of ursodeoxycholic acid-berberine supramolecular nanoparticles on ulcerative colitis based on supramolecular system induced by weak bond / 中国中药杂志

Ulcerative colitis(UC) is a recurrent, intractable inflammatory bowel disease. Coptidis Rhizoma and Bovis Calculus, serving as heat-clearing and toxin-removing drugs, have long been used in the treatment of UC. Berberine(BBR) and ursodeoxycholic acid(UDCA), the main active components of Coptidis Rhizoma and Bovis Calculus, respectively, were employed to obtain UDCA-BBR supramolecular nanoparticles by stimulated co-decocting process for enhancing the therapeutic effect on UC. As revealed by the characterization of supramolecular nanoparticles by field emission scanning electron microscopy(FE-SEM) and dynamic light scattering(DLS), the supramolecular nanoparticles were tetrahedral nanoparticles with an average particle size of 180 nm. The molecular structure was described by ultraviolet spectroscopy, fluorescence spectroscopy, infrared spectroscopy, high-resolution mass spectrometry, and hydrogen-nuclear magnetic resonance(H-NMR) spectroscopy. The results showed that the formation of the supramolecular nano-particle was attributed to the mutual electrostatic attraction and hydrophobic interaction between BBR and UDCA. Additionally, supramolecular nanoparticles were also characterized by sustained release and pH sensitivity. The acute UC model was induced by dextran sulfate sodium(DSS) in mice. It was found that supramolecular nanoparticles could effectively improve body mass reduction and colon shortening in mice with UC(P<0.001) and decrease disease activity index(DAI)(P<0.01). There were statistically significant differences between the supramolecular nanoparticles group and the mechanical mixture group(P<0.001, P<0.05). Enzyme-linked immunosorbent assay(ELISA) was used to detect the serum levels of tumor necrosis factor-α(TNF-α) and interleukin-6(IL-6), and the results showed that supramolecular nanoparticles could reduce serum TNF-α and IL-6 levels(P<0.001) and exhibited an obvious difference with the mechanical mixture group(P<0.01, P<0.05). Flow cytometry indicated that supramolecular nanoparticles could reduce the recruitment of neutrophils in the lamina propria of the colon(P<0.05), which was significantly different from the mechanical mixture group(P<0.05). These findings suggested that as compared with the mechanical mixture, the supramolecular nanoparticles could effectively improve the symptoms of acute UC in mice. The study provides a new research idea for the poor absorption of small molecules and the unsatisfactory therapeutic effect of traditional Chinese medicine and lays a foundation for the research on the nano-drug delivery system of traditional Chinese medicine.

New qualities control strategy of Scutellaria baicalensis by isothermal titration calorimetry / 中国中药杂志

It has been focused on that there will be precipitates when decoction of Scutellariat Radix mixed with Coptidis Rhizoma. Precipitation was derived from interaction between acidic and basic compounds. This study was based on the interaction between active ingredients after compatibility, strived to explore whether it was feasible to judge the qualities of different Scutellariat Radix by isothermal titration calorimetry (ITC), build a new method established to characterize the qualities of traditional Chinese medicine by taking a series of active ingredients as index. We selected Scutellariat Radix (including three batches of different Scutellariat Radix bought from market and immature Scutellariat Radix which usually was used as adulterant) in different batches as the samples. First, we used ITC to determine the binding heat of the reactions between berberine and the decoctions of different Scutellariat Radix. The test showed that the binding heat of berberine titrated Scutellariat Radix was Scutellariat Radix A (－317.20 μJ), Scutellariat Radix B (－292.83 μJ), Scutellariat Radix C (－208.95 μJ) and immature Scutellariat Radix (－21.53 μJ), respectively. We chose deionized water titrated by berberine (2.51 μJ) as control. The heat change of berberine titrated immature Scutellariat Radix was much less than berberine titrated Scutellariat Radix. Then we determined the absorbance of different decoctions of Scutellariat Radix by UV Spectrophotometry on the maximum absorption wavelength, and the result is： Scutellariat Radix A (0.372), Scutellariat Radix B (0.333), Scutellariat Radix C (0.272), immature Scutellariat Radix (0.124). The absorbance of immature Scutellariat Radix was also less than Scutellariat Radix. The result of ITC assay was corresponded to UV spectrophotometry test. In conclusion, ITC could be used to characterize the quality of Scutellariat Radix. The new method to characterize the qualities of traditional Chinese medicine by taking a kind of active ingredients as index building by ITC was simple, scientific and feasible.

Synthesis and protective effect of ligustrazine intermediates against CoCl2-induced neurotoxicity in differentiated PC12 cell / 中国中药杂志

Ligustrazine, one of the major effective components of the Chinese traditional medicinal herb Ligusticum Chuanxiong Hort, has been reported plenty of biological activities, such as protect cardiovascular and cerebrovascular, neuroprotection and anti-tumor, et al. Because of its remarkable effects, studies on structural modification of ligustrazine have attracted much attention. Ligustrazine synthetic derivatives reported in recent decades are mainly derived from four primary intermediates (TMP-COOH, TMP-OH, TMP-NH2, HO-TMP-OH). To explore the neuroprotection activitiy of ligustrazine intermediates, six ligustrazine intermediates (2, 5, 8, 11, 12, 13) were synthesized and their protective effects against CoCl2-induced neurotoxicity in differentiated PC12 cells were studied. The target compounds were prepared via different chemical methods, including oxidation, substitution, esterification and amidation without changing the structure nucleus of ligustrazine. Compared with TMP (EC50 = 56.03 micromol x L(-1)), four compounds (2, 5, 12 and 13) exhibited higher activity (EC50 < 50 micromol x L(-1)) respectively, of which, compound 2 displayed the highest protective effect against the damaged PC12 cells (EC50 = 32.86 micromol x L(-1)), but target compounds 8 and 11 appeared lower activity (EC50 > 70 micromol x L(-1)). By structure-activity relationships analysis, the introduction of carboxyl, amino to the side chain of ligustrazine and appropriately increase the proportion of ligustrazine may contribute to enhance its neuroprotective activity, which provides a reference for the design, synthesis and activity screening of relevant series of ligustrazine derivatives in the future.