Li Gao

Antiinflammatory and Analgesic Activities of Ethanol Extract and Isolated Compounds from Millettia pulchra

The plant Millettia pulchra was commonly used in folk medicine for the management of inflammation. However, there was no scientific rationale for these effects and the mechanism of action remained incompletely understood. The present study was designed to investigate the antiinflammatory and analgesic activities of an ethanol extract of the stem of M. pulchra (EMP) in vivo, and to explore the antiinflammatory activity of compounds isolated from EMP in vitro. We found that EMP reduced xylene-induced ear edema and relieved both acetic acid-induced pain and pain in the hot plate test. Additionally, a significant decrease in nitric oxide (NO) production was observed in cells treated with the isolated compounds. Lanceolatin B, which showed the greatest inhibition of NO synthesis among the compounds tested, also reduced levels of interleukin-1 beta (IL-1β), IL-6, tumor necrosis factor-alpha (TNF-α), cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), nuclear factor-kappa B (NF-κB), and phosphorylation inhibitory kappa B alpha (p-IκBα) in a dose-dependent manner. These findings provide convincing evidence that EMP and the individual isolated compounds possess significant antiinflammatory and analgesic activities.

Quantitative analysis of differential protein expression in cervical carcinoma cells after zeylenone treatment by stable isotope labeling with amino acids in cell culture

Cervical carcinoma is a malignant tumor that poses a serious threat to womens health and survival. Approximately 10-25% of cervical cancers are adenocarcinomas (ACs). AC has high rates of recurrence and mortality, while there is no effective treatment for now. Zeylenone (Zey), which is isolated from an ethanol extract of the leaves of Uvaria grandiflora Roxb. of the family Annonaceae, has shown potent inhibitory activity against various tumor cells, including cervical carcinoma cells. To gain insight into the molecular mechanism underlying the effect of Zey on AC, we quantified protein expression changes in AC cells treated with Zey. We used stable isotope labeling with amino acids in cell culture (SILAC) in combination with high-performance liquid chromatography-electrospray ionization tandem mass spectrometry (HPLC-ESI-MS/MS) and bioinformatics analysis to compare protein expression profiles in HeLa cells before and after Zey treatment. Of 1805 differentially expressed proteins identified, 229 were screened as key protein molecules and classified into nine categories. Profiling of differentially-expressed proteins contributed to our understanding of the molecular mechanism by which Zey induces HeLa cell apoptosis. Using this method, candidate targets can be identified for developing new drugs against cervical carcinoma.

Chemical constituents from the fruiting bodies of Cryptoporus volvatus

New drimane-type sesquiterpene cryptoporol A (1), cryptoporic acid derivative 6′-cryptoporic acid E methyl ester (2), and pseudouridine derivative cryptoporine A (3), as well as a known ergosterol 5α,8α-epidioxy-22E-ergosta-6,22-dien-3β-ol (4), were isolated from a 90xa0% alcohol extract of the fruiting bodies of Cryptoporus volvatus. The structures of these compounds were established by spectroscopic analysis and circular dichroism. 5α,8α-epidioxy-22E-ergosta-6,22-dien-3β-ol (4) exhibited antiviral activity against porcine reproductive and respiratory syndrome virus, and all compounds showed weak antioxidant activities.

Cryptoporus volvatus extract inhibits influenza virus replication in vitro and in vivo.

Influenza virus is the cause of significant morbidity and mortality, posing a serious health threat worldwide. Here, we evaluated the antiviral activities of Cryptoporus volvatus extract on influenza virus infection. Our results demonstrated that the Cryptoporus volvatus extract inhibited different influenza virus strain replication in MDCK cells. Time course analysis indicated that the extract exerted its inhibition at earlier and late stages in the replication cycle of influenza virus. Subsequently, we confirmed that the extract suppressed virus internalization into and released from cells. Moreover, the extract significantly reduced H1N1/09 influenza virus load in lungs and dramatically decreased lung lesions in mice. And most importantly, the extract protected mice from lethal challenge with H1N1/09 influenza virus. Our results suggest that the Cryptoporus volvatus extract could be a potential candidate for the development of a new anti-influenza virus therapy.

Umbelliprenin and lariciresinol isolated from a long-term-used herb medicine Ferula sinkiangensis induce apoptosis and G0/G1 arresting in gastric cancer cells

Effective chemicals isolated from folk medicine are commonly used in the treatment of cancer in Asian countries like China and India. Ferula sinkiangensis K. M. Shen is a traditional herb medicine used for treating stomach disorders in Xinjiang District of China for thousands of years. Here, we showed that the growth inhibition effects of seven compounds first isolated from the seeds of this herb in human gastric cancer cells and human normal gastric epithelium cells. Furthermore, we characterized the mechanism of the antiproliferation effects on gastric cancer cells of the two most specific and effective compounds: umbelliprenin (UM) and lariciresinol (LA). Annexin V/PI staining demonstrated that UM and LA induce apoptosis in gastric cancer AGS cells. Loss of mitochondrial membrane potential, upregulation of proapoptotic protein BAX, and activation of caspase 3 and PARP suggested that UM and LA caused the activation of the mitochondrial apoptosis pathway. Cell cycle analysis showed that UM and LA arrest cell cycle at G0/G1 phase. Western blot results showed that the expression of P53, P27, P16 and Rb proteins increased, while the expression of cyclin D, cyclin E, Cdk4 and Cdk2 decreased in cancer cells. Overall, these data provided evidence that UM and LA have the potential to be used in cancer therapy.

Zeylenone, a naturally occurring cyclohexene oxide, inhibits proliferation and induces apoptosis in cervical carcinoma cells via PI3K/AKT/mTOR and MAPK/ERK pathways.

There is a strong rationale to therapeutically target the PI3K/Akt/mTOR and MAPK/ERK pathways in cervical carcinoma since they are highly deregulated in this disease. Previous study by our group have demonstrated that Zeylenone (Zey) exhibited strong suppressive activity on PI3K/AKT/mTOR and MAPK/ERK signaling, providing a foundation to investigate its antitumor activity in cervical carcinoma. Herein, the present study aimed to investigate suppressive effect of Zey on HeLa and CaSki cells, and further explore the underlying mechanisms. Cells were treated with Zey for indicated time, followed by measuring its effects on cell viability, colony formation, cell cycle, cell apoptosis, and signal pathways. In vivo antitumor activity of Zey was then assessed with nude xenografts. We found that Zey substantially suppressed cell proliferation, induced cell cycle arrest, and increased cell apoptosis, accompanied by increased production of ROS, decreased mitochondrial membrane potential, activated caspase apoptotic cascade, and attenuated PI3K/Akt/mTOR and MAPK/ERK pathways. Additionally, in vivo experiments showed that Zey exerted good antitumor efficacy against HeLa bearing mice models via decreasing levels of p-PI3K and p-ERK. Collectively, these data clearly demonstrated the antitumor activity of Zey in cervical carcinoma cells, which is most likely via the regulation of PI3K/Akt/mTOR and MAPK/ERK pathways.

An unusual sesquiterpene coumarin from the seeds of Ferula sinkiangensis

Abstract A sesquiterpene coumarin, sinkiangenorin E, consisting of a novel bicyclo[4.3.1]decane-type sesquiterpene system, was isolated from the seeds of Ferula sinkiangensis. The structure of sinkiangenorin E including the relative stereochemistry and the absolute configuration was elucidated on the basis of spectroscopic data. The new compound showed cytotoxic activity against AGS cells (IC50, 12.7 μM) and inhibiting effect against influenza A H1N1 (IC50, 4.0 μM), which provided important clues for the study on the bioactivities of this type of sesquiterpene coumarins.

Flavonoids Extracted from Licorice Prevents Colitis-Associated Carcinogenesis in AOM/DSS Mouse Model

Inflammatory bowel disease (IBD) is generally considered as a major risk factor in the progression of colitis-associated carcinogenesis (CAC). Thus, it is well accepted that ameliorating inflammation creates a potential to achieve an inhibitory effect on CAC. Licorice flavonoids (LFs) possess strong anti-inflammatory activity, making it possible to investigate its pharmacologic role in suppressing CAC. The purpose of the present study was to evaluate the anti-tumor potential of LFs, and further explore the underlying mechanisms. Firstly, an azoxymethane (AOM)/dextran sulfate sodium (DSS)-induced mouse model was established and administered with or without LFs for 10 weeks, and then the severity of CAC was examined macroscopically and histologically. Subsequently, the effects of LFs on expression of proteins associated with apoptosis and proliferation, levels of inflammatory cytokine, expression of phosphorylated-Janus kinases 2 (p-Jak2) and phosphorylated-signal transducer and activator of transcription 3 (p-Stat3), and activation of nuclear factor-κB (NFκB) and P53 were assessed. We found that LFs could significantly reduce tumorigenesis induced by AOM/DSS. Further study revealed that LFs treatment substantially reduced activation of NFκB and P53, and subsequently suppressed production of inflammatory cytokines and phosphorylation of Jak2 and Stat3 in AOM/DSS-induced mice. Taken together, LFs treatment alleviated AOM/DSS induced CAC via P53 and NFκB/IL-6/Jak2/Stat3 pathways, highlighting the potential of LFs in preventing CAC.

Hepatoprotective Effect of Aqueous Extract from the Seeds of Orychophragmus violaceus against Liver Injury in Mice and HepG2 Cells

Orychophragmus violaceus (O. violaceus) is a kind of edible wild herb in north China and its seeds have medical potential, however, the effect of O. violaceus seeds on liver injury and the mechanism of action remains poorly understood. Thus, the purpose of the present study is to investigate the effect of O. violaceus seeds on liver injury and further explore the molecular mechanism of the beneficial effects using aqueous extract from the seeds of O. violaceus (AEOV). Mice were orally administrated with saline, AEOV, and biphenyldicarboxylate for 4 days, and were then injected subcutaneously with 0.1% carbon tetrachloride (CCl4) dissolved in corn oil. Sixteen hours later, mice were sacrificed and blood samples were collected. Then, the serum was separated and used for biochemical assay. Livers were excised and were routinely processed for histological examinations. Enzyme activities and protein levels in liver homogenates were detected using commercial kits or by western blot analysis. Additionally, the hepatoprotective effect of AEOV in vitro was evaluated using epigoitrin, the major alkaloid compound isolated from AEOV. We found that AEOV attenuated liver injury induced by CCl4 as evidenced by decreased levels of alanine aminotransferase (ALT) and aminotransferase (AST) in serum, improvement of liver histopathological changes, and substantial attenuation of oxidative stress and inflammation via regulation of nuclear factor-erythroid 2-related factor-2 (Nrf2) and nuclear factor κB (NFκB) pathways. These effects of AEOV were comparable to that of biphenyldicarboxylate which was commonly used as a hepatoprotective reference. Moreover, pretreatment of HepG2 cells with epigoitrin improved cell viability, decreased lactate dehydrogenase (LDH) and malondialdehyde (MDA) levels, increased superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activity, attenuated the NFκB pathway, and elevated the Nrf2 pathway after exposure to H2O2. These results suggest that AEOV could effectively prevent CCl4-induced liver injury in mice via regulating the Nrf2 and NFκB pathways, and reveal the cytoprotective effects of epigoitrin against H2O2-induced oxidative stress in HepG2 cells.

Anti-inflammatory and Anti-oxidant Effects of Licorice Flavonoids on Ulcerative Colitis in Mouse Model

Abstract Objective Licorice (Glycyrrhizae Radix or Liquiritiae Radix) is traditionally used to treat various diseases including inflammation and gastric ulcers. Licorice is rich in flavonoid compounds and possesses anti-inflammatory activities. To investigate the protective effects of licorice flavonoids (LFs) in both acetic acid-induced and dextran sulphate sodium (DSS)-induced ulcerative colitis (UC) mouse model and its underlying mechanism. Acute UC was induced by intra-rectal acetic acid (4% v/v) after pretreatment with LFs (100, 200, and 400 mg/kg, p.o.), 0.9% saline (20 mL/kg, p.o.) or Sulfasalazine (SASP) (600 mg/kg, p.o.) for 10 d. Quantitative analysis of chemical components of LFs was also conducted by HPLC. Our results showed that pre-treatment with LFs significantly reduced the wet weight/length ratio of colon, percentage of affected area, macroscopic and histological damage scores in acid-induced UC mice. LFs also significantly decreased the oxidative stress and pro-inflammatory cytokines, upregulated nuclear factor erythroid 2-related factor 2 (Nrf2) pathway and downregulated nuclear transcription factor kappa B (NF-κB) pathway. At last, LFs also showed obvious antiulcer effect on the DSS-induced UC model. The major components of LFs were licochalcone A, glabrone, licoflavone, and licoflavone B. This study demonstrates that the protective effect of LFs may at least in part be due to its anti-oxidant activity through Nrf2 pathway and anti-inflammatory activity through NF-κB pathway.