[Therapeutic effect of ursodeoxycholic acid-berberine supramolecular nanoparticles on ulcerative colitis based on supramolecular system induced by weak bond].

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.

Anti-tumor effects of novel alkannin derivatives with potent selectivity on comprehensive analysis.

BACKGROUND: Therapeutic approaches based on glycolysis and energy metabolism of tumor cells are new promising strategies for the treatment of cancer. Currently, researches on the inhibition of pyruvate kinase M2, a key rate limiting enzyme in glycolysis, have been corroborated as an effective cancer therapy. Alkannin is a potent pyruvate kinase M2 inhibitor. However, its non-selective cytotoxicity has affected its subsequent clinical application. Thus, it needs to be structurally modified to develop novel derivatives with high selectivity. PURPOSE: Our study aimed to ameliorate the toxicity of alkannin through structural modification and elucidate the mechanism of the superior derivative 23 in lung cancer therapy. METHODS: On the basis of the principle of collocation, different amino acids and oxygen-containing heterocycles were introduced into the hydroxyl group of the alkannin side chain. We examined the cell viability of all derivatives on three tumor cells (HepG2, A549 and HCT116) and two normal cells (L02 and MDCK) by MTT assay. Besides, the effect of derivative 23 on the morphology of A549 cells as observed by Giemsa and DAPI staining, respectively. Flow cytometry was performed to assess the effects of derivative 23 on apoptosis and cell cycle arrest. To further assess the effect of derivative 23 on the Pyruvate kinase M2 in glycolysis, an enzyme activity assay and western blot assay were performed. Finally, in vivo the antitumor activity and safety of the derivative 23 were evaluated by using Lewis mouse lung cancer xenograft model. RESULTS: Twenty-three novel alkannin derivatives were designed and synthesized to improve the cytotoxicity selectivity. Among these derivatives, derivative 23 showed the highest cytotoxicity selectivity between cancer and normal cells. The anti-proliferative activity of derivative 23 on A549 cells (IC50 = 1.67 ± 0.34 µM) was 10-fold higher than L02 cells (IC50 = 16.77 ± 1.44 µM) and 5-fold higher than MDCK cells (IC50 = 9.23 ± 0.29 µM) respectively. Subsequently, fluorescent staining and flow cytometric analysis showed that derivative 23 was able to induce apoptosis of A549 cells and arrest the cell cycle in the G0/G1 phase. In addition, the mechanistic studies suggested derivative 23 was an inhibitor of pyruvate kinase; it could regulate glycolysis by inhibiting the activation of the phosphorylation of PKM2/STAT3 signaling pathway. Furthermore, studies in vivo demonstrated derivative 23 significantly inhibited the growth of xenograft tumor. CONCLUSION: In this study, alkannin selectivity is reported to be significantly improved following structural modification, and derivative 23 is first shown to be able to inhibit lung cancer growth via the PKM2/STAT3 phosphorylation signaling pathway in vitro, indicating the potential value of derivative 23 in treating lung cancer.

[Material basis of Rhei Radix et Rhizoma-Coptidis Rhizoma combination in alleviating "bitter-cold" properties based on supramolecular chemistry of Chinese medicine].

The present study aimed to explore the material basis of Rhei Radix et Rhizoma-Coptidis Rhizoma combination in alleviating "bitter-cold" properties based on the supramolecular chemistry of Chinese medicine.Dynamic light scattering and scanning/transmission electron microscopy were used to characterize the morphological characteristics of supramolecules in the decoction of Rhei Radix et Rhizoma and Coptidis Rhizoma.The chemical composition of supramolecules, as well as the dissolution and release processes of supramolecules and the medicinal components of Coptidis Rhizoma decoction, was determined by the high-performance liquid chromatography-mass spectrometry.The differences in "bitter-cold" medicinal properties between Rhei Radix et Rhizoma decoction, Coptidis Rhizoma decoction, and co-decoction were analyzed by sensory evaluation, electronic tongue, mouse diarrhea model, and pathological indicators.The anthraquinones/tannins and alkaloids interacted to form supramolecules with a scale of about 400 nm when Rhei Radix et Rhizoma and Coptidis Rhizoma were decocted together, which delayed the dissolution and release of the active components represented by berberine. Compared with the consequence of single drug administration at 4 g·kg~(-1), the combination of the two drugs at 8 g·kg~(-1) significantly alleviated the "bitter-cold" properties.The effective components interacted to form supramolecules in the co-decoction of Rhei Radix et Rhizoma and Coptidis Rhizoma, which affected the dissolution and release of the effective components of Chinese medicinal decoction, thereby alleviating the "bitter-cold" properties.The findings of this study provide a new idea for revealing the scientific compatibility of Rhei Radix et Rhizoma and Coptidis Rhizoma.

Synthesis and biological activity evaluation of podophyllotoxin-linked bile acid derivatives as potential anti-liver cancer agents.

Podophyllotoxin's undifferentiated cytotoxicity and poor selectivity limit its clinical application. To improve above disadvantages, conjugation of bile acids with podophyllotoxin could improve cell line selectivity of liver cancer to achieve clinical translation further. Enlightened by the bile acids' moiety magic characters, thirty podophyllotoxin-linked bile acid derivatives had been designed and synthesized. The cytotoxicity of these compounds in vitro was evaluated on HepG2, HCT-116, A549 and MDCK cell lines. After conjunction with bile acids, most of the derivatives (IC50 = 0.066-0.831 µM) were more potent against above three types of tumor cells than Etoposide (VP-16, IC50 = 4.319-41.080 µM) and exhibited similar antitumor activity compared with doxorubicin (DOX, IC50 = 0.230-0.745 µM). Moreover, structure-activity relationship displayed the length of the linker chain between podophyllotoxin and bile acids affected the cytotoxicity. Especially, compound 23 exhibited strong activity against HepG2 cell lines (IC50 = 0.188 ± 0.01 µM) than MDCK cell lines (IC50 = 4.780 ± 0.50 µM) and its SI (IC50MDCK/IC50HepG2) value of compound 23 was 25.4. Further antitumor mechanism studies showed that compound 23 acted as Topo Ⅱ inhibition and induced cell apoptosis with S cell cycle arrest. In particular, compound 23 showed valid antitumor efficacy at 10 mg/kg by intraperitoneal administration with a tumor inhibition rate of 60.9% in the Hepa1-6 xenograft mice model. The current research displayed that introduction of bile acids contributed to improve selectivity and activity to cell, and compound 23 could be a promising anti-tumor candidate.

[Explore antioxidant quality markers of Hippophae tibetana based on "dry-method + wet-method" technology].

The cross combination of dry-method(network pharmacology analysis) and wet-method(high-resolution mass spectro-metry with antioxidation experiment) was used to predict antioxidant quality markers(Q-markers) of Hippophae tibetana. Ultra-high performance liquid chromatography coupled with hybrid quadrupole-orbitrap mass spectrometry(UPLC-Q-Exactive Orbitrap-MS) was developed to rapidly separate and identify the chemical constituents in H. tibetana. Then in DPPH free radicals and superoxide anion scavenging experiment, the antioxidant activity of the four different polar parts with extracts of petroleumether, ethyl acetate, n-butanol and water was evaluated. Network pharmacology method was used for functional enrichment and pathway analysis to screen antioxidant-related components and preliminarily explain the mechanism of action. On this basis, multi-source information was integrated to predict the antioxidant Q-markers. The results showed that 51 components in H. tibetana were identified, including 18 flavonoids, 14 terpenoids, 6 alkaloids, 4 coumarins and phenylpropanoids, 3 volatile components and 2 polyphenols. The antioxidant capacity of different fractions: ethyl acetate > n-butanol > water > petroleum ether. The medicine mainly acted on PI3 K-Akt and FoxO signaling pathways to perform antioxidant effects through flavonoids such as quercetin, luteolin and kaempferol. According to the results of dry-method and wet-method, quercetin, luteolin and kaempferol, the representatives of poly-hydroxy flavone, may be the antioxidant Q-markers of H. tibetana. In this study, with the antioxidant Q-markers of H. tibetana as an example, an investigation model of predicting Q-marker was discussed based on the ternary system of composition, function and informatics, providing a scientific basis for the establishment of quality evaluation standards for H. tibetana.

Design, synthesis, and biological evaluation of ligustrazine - betulin amino-acid/dipeptide derivatives as anti-tumor agents.

The ligustrazine - betulin derivative (TB), TB amino acids derivatives (TB-01 - TB-09) and TB dipeptide derivatives (TB-10 - TB-18) were designed and synthesized. And their in vitro cytotoxic activities were evaluated against four cancer cell lines (Hela, HepG2, BGC-823 and HT-29) and normal cells MDCK by standard methylthiazol tetrazolium (MTT) assay. Most of them demonstrated better antitumor activity than the relevant material betulin. Among them, compound TB-01 showed the best anti-tumor effect on the cancer cells and the lowest toxicity on the normal cells. For example, the cytotoxicity of TB-01 against the cancer cells (mean IC50 = 4.86 ±â€¯1.16 µM) was 3-fold higher than that against the normal cells MDCK (IC50 = 16.11 ±â€¯2.29 µM). Moreover, TB-01 showed better cytotoxic than positive drug cisplatin (DDP) on tumor cells. Besides, the Zebrafish toxicity evaluation test showed that TB-01 demonstrated high biosafety. Subsequently, fluorescent staining, apoptosis detection and cell cycle analysis indicated that TB-01 induced early apoptosis in HepG2 cells and blocked the cell cycle in the G1 phase. In addition, the structure-activity relationships of these derivatives were briefly discussed.

Design, synthesis and biological evaluation of cinnamic acid derivatives with synergetic neuroprotection and angiogenesis effect.

As for complex brain diseases involved with multiple pathogenic factors, it is extremely difficult to achieve curative effect by acting on a single target. Multi-approach drugs provide a promising prospect in the treatment of complex brain diseases and have been attracting more and more interest. Enlightened by synergetic effect of combination in traditional herb medicines, forty-two novel cinnamic acid derivatives were designed and synthesized by introducing capsaicin and/or ligustrazine moieties to enhance biological activities in both neurological function and neurovascular protection. Elevated levels of cell viability on human brain microvascular endothelium cell line (HBMEC-2) and human neuroblastoma cell line (SH-SY5Y) against free radical injury were observed in most of compounds. Among them, compound 14a exhibited the most potent activities with a significant EC50 value of 3.26 ±â€¯0.16 µM (HBMEC-2) and 2.41 ±â€¯0.10 µM (SH-SY5Y). Subsequently, the results of morphological staining and flow cytometry analysis experiments on both cell lines showed that 14a had the potential to block apoptosis, maintain cell morphological integrity and protect physiological function of mitochondria. Moreover, 14a displayed specific angiogenesis effect in the chick chorioallantoic membrane (CAM) assay; and the results of RT-PCR suggested that the mechanism for angiogenesis effect was associated with the enhancement of the expressions of VEGFR2 mRNA in chick embryo. Preliminary structure-activity relationship was analyzed. The above evidences suggested that conjunctures gained by combining active ingredients in traditional herb medicines deserved further study and might provide references in discovering dual-effective lead compounds for brain diseases.

Synthesis and biological activity of glycyrrhetinic acid derivatives as antitumor agents.

Glycyrrhetinic acid (GA) had been the star anticancer lead compound and appealed to many scientists all over the world; however, its antitumor activity was not potent enough. To improve GA's cytoxicity and explore the effect of bonding mode on antitumor activity, 32 compounds including GA-OH series (GO, esters in C-3 position) and GA-NH2 series (GN, with amide linkages in C-3 position) had been designed and synthesized. All the compounds were screened for in vitro cytotoxicity against A549, HepG2, MCF-7, Hela and MDCK cell lines. As a result, all the de-protected (without Boc group) derivatives showed much stronger cytotoxic activity than GA, and surprisingly enough, all the GN series of the compounds were more potent than GO series against various tumor cells. Among them, the compound 26 (amide linkages in C-3 position) exhibited stronger antitumor activity against A549 cell line (IC50 = 2.109 ±â€¯0.11 µM) than the positive drug cisplatin (IC50 = 9.001 ±â€¯0.37 µM). Further studies indicated that compound 26 could induce A549 apoptosis via nuclei fragmentation. The detection of apoptosis and cell cycle analysis indicated that compound 26 could induce the early apoptosis and prevent A549 cells transition from S to G2 phase. Furthermore, the structure-activity relationships were briefly discussed. Among which, current study displayed amide linkages in C-3 position could effectively enhance GA cytotoxicity, providing a new modification strategy for further study.

Design, Synthesis, and Cytotoxic Analysis of Novel Hederagenin⁻Pyrazine Derivatives Based on Partial Least Squares Discriminant Analysis.

Hederagenin (He) is a novel triterpene template for the development of new antitumor compounds. In this study, 26 new He⁻pyrazine derivatives were synthetized in an attempt to develop potent antitumor agents; they were screened for in vitro cytotoxicity against tumor and non-tumor cell lines. The majority of these derivatives showed much stronger cytotoxic activity than He. Remarkably, the most potent was compound 9 (half maximal inhibitory concentration (IC50) was 3.45 ± 0.59 µM), which exhibited similar antitumor activities against A549 (human non-small-cell lung cancer) as the positive drug cisplatin (DDP; IC50 was 3.85 ± 0.63 µM), while it showed lower cytotoxicity on H9c2 (murine heart myoblast; IC50 was 16.69 ± 0.12 µM) cell lines. Compound 9 could induce the early apoptosis and evoke cell-cycle arrest at the synthesis (S) phase of A549 cells. Impressively, we innovatively introduced the method of cluster analysis modeled as partial least squares discriminant analysis (PLS-DA) into the structure⁻activity relationship (SAR) evaluation, and SAR confirmed that pyrazine had a profound effect on the antitumor activity of He. The present studies highlight the importance of pyrazine derivatives of He in the discovery and development of novel antitumor agents.

PSMA-Oriented Target Delivery of Novel Anticancer Prodrugs: Design, Synthesis, and Biological Evaluations of Oligopeptide-Camptothecin Conjugates.

Clinical applications of camptothecin (CPT) have been heavily hindered due to its non-targeted toxicity, active lactone ring instability, and poor water solubility. Targeted drug delivery systems may offer the possibility to overcome the above issues as reported. In this research, a series of prostate-specific membrane antigen (PSMA)-activated CPT prodrugs were designed and synthesized by coupling water-soluble pentapeptide, a PSMA hydrolyzing substrate, to CPT through an appropriate linker. The cytotoxicity of CPT prodrugs was masked temporarily until they were hydrolyzed by the PSMA present within the tumor sites, which restored cytotoxicity. The in vitro selective cytotoxic activities of the prodrugs were evaluated against PSMA-expressing human prostate cancer cells LNCaP-FGC and non-PSMA-expressing cancer cells HepG2, Hela, MCF-7, DU145, PC-3 and normal cells MDCK, LO2 by standard methylthiazol tetrazolium (MTT) assay. Most of the newly synthesized CPT prodrugs showed excellent selective toxicity to PSMA-producing prostate cancer cells LNCaP-FGC with improved water solubility. From among the library, CPT-HT-J-ZL12 showed the best cytotoxic selectivity between the PSMA-expressing and the non-PSMA-expressing cancer cells. For example, the cytotoxicity of CPT-HT-J-ZL12 (IC50 = 1.00 ± 0.20 µM) against LNCaP-FGC (PSMA⁺) was 40-fold, 40-fold, 21-fold, 5-fold and 40-fold, respectively, higher than that against the non-PSMA-expressing cells HepG2 (IC50 > 40.00 µM), Hela (IC50 > 40.00 µM), MCF-7 (IC50 = 21.68 ± 4.96 µM), DU145 (IC50 = 5.40 ± 1.22 µM), PC-3 (IC50 = 42.96 ± 3.69 µM) cells. Moreover, CPT-HT-J-ZL12 exhibited low cytotoxicity (IC50 > 40 µM) towards MDCK and LO2 cells. The cellular uptake experiment demonstrated the superior PSMA-targeting ability of the CPT-HT-J-ZL12, which was significantly accumulated in LNCaP-FGC (PSMA⁺), while it was minimized in HepG2 (PSMA-) cells. Further cell apoptosis analyses indicated that it showed a dramatically higher apoptosis-inducing activity in LNCaP-FGC (PSMA⁺) cells than in HepG2 (PSMA-) cells. Cell cycle analysis indicated that CPT-HT-J-ZL12 could induce cell cycle arrest at the S phase.

Synthesis and biological evaluation of podophyllotoxin derivatives as selective antitumor agents.

To improve podophyllotoxin's cytotoxicity and selective effect, twenty-two podophyllotoxin derivatives had been designed and synthesized. The cytotoxicity of these compounds was evaluated on A549, MCF-7, HepG2 and L-02 cell lines. As a result, most of the compounds were more potent than the positive drugs Etoposide (VP-16) and Doxorubicin which were widely used in clinical for antitumor. There were no magnitude differences about these de-protected (without Boc group) podophyllotoxin amino acid derivatives' cytotoxicity between three tumor cell lines and normal hepatic L-02 cells. Interestingly, some protected (with Boc group) amino acid derivatives and some ligustrazine derivatives showed high selectivity, especially the compound 2 (sarcosine derivative with Boc group). It exhibited highly selectivity both on the cancer cells and the normal cells. The IC50 of compound 2 was 9.5 ±â€¯0.03 nM, 132.6 ±â€¯24.1 nM, 96.4 ±â€¯1.3 nM and 160.2 ±â€¯4.7 nM against A549, MCF-7, HepG2 and L-02 cells, respectively. The SI (IC50L-02/IC50A549) value of compound 2, Doxorubicin and Etoposide was 16.9, 0.2 and 0.5, respectively. Meanwhile, SI (IC50MCF-7/IC50A549) value and SI (IC50HepG2/IC50A549) value of compound 2 were 14.0 and 10.1, respectively. In summary, compound 2 showed high selectivity especially on A549 cells. Further research on cell apoptosis indicated that compound 2 could induce apoptosis of A549 cells through nuclei fragmentation and had lower toxicity to normal hepatic L-02 cells. The detection of apoptosis and cell cycle analysis indicated that compound 2 induced A549 cells apoptosis and prevented A549 cells transition from S to G2 phase while there were no obvious changes on L-02 cells. Moreover, the structure-activity relationships of these derivatives were briefly discussed.

An Overview of Structurally Modified Glycyrrhetinic Acid Derivatives as Antitumor Agents.

Glycyrrhetinic Acid (GA), a triterpenoid aglycone component of the natural product glycyrrhizinic acid, was found to possess remarkable anti-proliferative and apoptosis-inducing activity in various cancer cell lines. Though GA was not as active as other triterpenes, such as betulinic acid and oleanolic acid, it could trigger apoptosis in tumor cells and it can be obtained easily and cheaply, which has stimulated scientific interest in using GA as a scaffold to synthesize new antitumor agents. The structural modifications of GA reported in recent decades can be divided into four groups, which include structural modifications on ring-A, ring-C, ring-E and multiple ring modifications. The lack of a comprehensive and recent review on this topic prompted us to gather more new information. This overview is dedicated to summarizing and updating the structural modification of GA to improve its antitumor activity published between 2005 and 2016. We reviewed a total of 210 GA derivatives that we encountered and compiled the most active GA derivatives along with their activity profile in different series. Furthermore, the structure activity relationships of these derivatives are briefly discussed. The included information is expected to be of benefit to further studies of structural modifications of GA to enhance its antitumor activity.

Bioactive Components from Qingwen Baidu Decoction against LPS-Induced Acute Lung Injury in Rats.

Qingwen Baidu Decoction (QBD) is an extraordinarily "cold" formula. It was traditionally used to cure epidemic hemorrhagic fever, intestinal typhoid fever, influenza, sepsis and so on. The purpose of this study was to discover relationships between the change of the constituents in different extracts of QBD and the pharmacological effect in a rat model of acute lung injury (ALI) induced by lipopolysaccharide (LPS). The study aimed to discover the changes in constituents of different QBD extracts and the pharmacological effects on acute lung injury (ALI) induced by LPS. The results demonstrated that high dose and middle dose of QBD had significantly potent anti-inflammatory effects and reduced pulmonary edema caused by ALI in rats (p < 0.05). To explore the underlying constituents of QBD, we assessed its influence of six different QBD extracts on ALI and analyzed the different constituents in the corresponding HPLC chromatograms by a Principal Component Analysis (PCA) method. The results showed that the pharmacological effect of QBD was related to the polarity of its extracts, and the medium polarity extracts E2 and E5 in particular displayed much better protective effects against ALI than other groups. Moreover, HPLC-DAD-ESI-MSn and PCA analysis showed that verbascoside and angoroside C played a key role in reducing pulmonary edema. In addition, the current study revealed that ethyl gallate, pentagalloylglucose, galloyl paeoniflorin, mudanpioside C and harpagoside can treat ALI mainly by reducing the total cells and infiltration of activated polymorphonuclear leukocytes (PMNs).

Combination of amino acid/dipeptide with ligustrazine-betulinic acid as antitumor agents.

The lead compound TBA, 3ß-Hydroxy-lup-20(29)-ene-28-oic acid-3, 5, 6-trimethylpyrazin-2-methyl ester, which exhibited promising antitumor activity and induced tumor cell apoptosis in various cancer cell lines, had previously been reported. Moreover, reports have revealed that the introduction of amino acid to betulinic acid could improve selective cytotoxicity as well as water solubility. Thus, a series of novel TBA amino acid and dipeptide derivatives were designed, synthesized and screened for selective cytotoxic activity against five cancer cell lines (HepG2, HT-29, Hela, BCG-823 and A549) and the not malignant cell line MDCK by standard MTT assay. Most of the tested TBA-amino acid and dipeptide analogues showed stronger anti-proliferative activity against all tested tumor cell lines than TBA. Among them, BA-25 exhibited the greatest cytotoxic activity on tumor cell lines (mean IC50 = 2.31 ± 0.78 µM), that was twofold than the positive drug cisplatin (DDP), while it showed lower cytotoxicity on MDCK cell line than DDP. Further cell apoptosis analyses indicated BA-25-induced apoptosis was associated with loss of mitochondrial membrane potential and increase of intracellular free Ca2+ concentration.

Preparation and physicochemical characterization of a solid dispersion of (3, 5, 6-trimethylpyrazin-2-yl) methyl 3-methoxy-4-[(3, 5, 6-trimethylpyrazin-2-yl) methoxy] benzoate (VA-T) and polyvinylpyrrolidone.

Ischemic brain injury is a major disease which threatens human health and safety. (3, 5, 6-trimethylpyrazin-2-yl) methyl 3-methoxy-4-[(3, 5, 6-trimethylpyrazin-2-yl) methoxy] benzoate (VA-T), a newly discovered lead compound, is effective for the treatment of ischemic brain injury and its sequelae. But the poor solubility of VA-T leads to poor dissolution and limited clinical application. In order to improve the dissolution of VA-T, the pharmaceutical technology of solid dispersions was used in the present study. VA-T/polyvinylpyrrolidone (PVP) solid dispersion was prepared by the solvent method. The dissolution studies were carried out and solid state characterization was evaluated by differential scanning calorimetry (DSC), infrared spectroscopy (IR), x-ray diffraction (XRD) and scanning electron microscopy (SEM). The dissolution rate of VA-T was significantly improved by solid dispersion compared to that of the pure drug and physical mixture. The results of DSC and XRD indicated that the VA-T solid dispersion was amorphous. The IR spectra showed the possible interaction between VA-T and PVP was the formulation of hydrogen bonding. The SEM analysis demonstrated that there was no VA-T crystal observed in the solid dispersions. The ideal drug-to-PVP ratio was 1:5. In conclusion, the solid dispersion technique can be successfully used for the improvement of the dissolution profile of VA-T.

In vitro evaluation of antiviral activity of tea seed saponins against porcine reproductive and respiratory syndrome virus.

BACKGROUND: Porcine reproductive and respiratory syndrome virus (PRRSV) is one of the major swine pathogens. This virus causes immune suppression and other secondary infections, leading to significant economic losses in the swine industry. Tea seed saponins (TS) are a natural extract from tea seeds with anti-cancer, anti-inflammatory and antiviral activity. In this study, we demonstrated that TS possessed anti-PRRSV activity. METHODS: MTT assay and trypan blue staining were used to evaluate the cytotoxicity and antiviral ability of TS in cell culture. Apoptosis was measured to assess the safety of TS on Marc-145 cells. Time-of-addition assay, entry inhibition assay and virucidal assay were used to assess the antiviral action of TS. The effect of TS on host cellular gene expression was analysed by real-time PCR. Absolute quantification RT-PCR and western blot were used to study the inhibitory effect of TS on PRRSV N gene and protein expression. RESULTS: Our results showed that 50% cytotoxic concentrations (CC50) and 50% effective concentration (EC50) of TS were 59.86 ±0.3841 µg/ml and 24.29 ±1.194 µg/ml, respectively. The maximum non-cytotoxic concentration of TS on Marc-145 cells was 30 µg/ml. TS inhibited PRRSV-induced cell apoptosis and effectively inhibited PRRSV replication by reducing the expression of host cellular gene PABP, and significantly inhibited virus N gene/protein expression. CONCLUSIONS: TS possessed anti-PRRSV activity in vitro and could serve as a potential antiviral drug for PRRSV prevention and control.

[Synthesis and protective effect of ligustrazine intermediates against CoCl2-induced neurotoxicity in differentiated PC12 cell].

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.

[Identification of metabolites of antitumor lead compound T-OA in rat urine by HPLC-HRMS].

OBJECTIVE: To study the major metabolites of antitumor lead compound T-OA (oleanolic acyl-3, 5, 6-trimethyl pyrazine-2-methyl ester) in rat urine, in order to preliminarily infer its metabolic mode in rats. METHOD: Rat urines of the blank group, the raw material group (ligustrazine TMP and oleanolic acid OA Moore equivalent) and the T-OA group were collected and freeze-dried; Solids were extracted by ethyl acetate; And then the extracts were re-dissolved with acetonitrile. HPLC-HRMS coupling technique was adopted to find the potential mass spectrum peak under ESI(+) (see symbol) ESI(-) modes. Metabolite-related information was obtained by comparing the three groups of spectra. RESULT: One metabolite of OA and two metabolites of TMP were identified in the raw material group; none metabolite of T-OA but one phase II metabolite was detected in the T-OA group. CONCLUSION: It is the first time to identify one phase II metabolite of T-OA and one phase II metabolite of OA were identified in rat urine. On that basis, the researchers preliminarily inferred that T-OA does not show the efficacy in the form of raw material. The HPLC-HRMS method established could be used to identify metabolites of related derivative structures. This paper could also provide certain reference for designing pro-drugs based on oleanolic acid.

[Spectrum-effect relationship of Moutan cortex against lipopolysaccharide-induced acute lung injury].

This research is to study the relationship between HPLC fingerprints of Moutan Cortex, Paeoniae Radix Rubra and Paeoniae Radix Alba and their activity on lipopolysaccharide-induced acute lung injury. HPLC fingerprints of each extract of Moutan Cortex,Paeoniae Radix Rubra and Paeoniae Radix Alba were established by an optimized HPLC-MS method. The activities of all samples against protein and tumor necrosis a factor were tested by the model of lipopolysaccharide-induced acute lung injury. The possible relationship between HPLC-MS fingerprints and the activitieswere deduced by the Partial least squares regression analysis method. Samples were analyzed by HPLC-MS/MS to identify the major peaks. The results showed that each sample had some effect on acute lung injury. Four components with a lager contribution rate of efficacy were calculated by the research of spectrum-effect relationship. Moutan Cortex exhibited good activity on acute lung injury, and gallic acid, paeoniflorin, galloylpaeoniflorin and paeonol were the main effective components.

[Synthesis and characterization of protocatechuic acid derivants].

To explore the effects of protocatechuic acid (PCA) and its derivants on angiogenesis of the chick embryo chorioallantoic membrane (CAM) and scavenging DPPH radical in vitro. The protection of benzyl and alkaline hydrolysis of benzyl ester were employed. The structures of PCA-1, PCA-2 and PCA-3, the derivates of PCA, were elucidated by 1H, 13C-NMR and MS data The bioactivity of PCA and its derivants was evaluated on the models of DPPH radical and chick embryo chorioallantoic membrane (CAM), respectively. PCA and PCA-1 showed the best activity of scavenging DPPH radical among all the compounds. In contrast to PCA-2, PCA and PCA-3 displayed inhibition to angiogenesis (P < 0.001). Pyrocatechol hydroxyl is the active site of PCA on scavenging DPPH radical in vitro. PCA with carboxyl and without pyrocatechol hydroxyl seems to show promotion to angiogenesis, but it needs more evidences.