Xiaobin Jia

Identification of two polysaccharides from Prunella vulgaris L. and evaluation on their anti-lung adenocarcinoma activity.

Prunella vulgaris L. (PV) has been used for tumor therapy in Traditional Chinese Medicine for centuries, however, systematic research on extracted PV polysaccharides believed to possess various biological activities, as well as their preventive and anti-tumor effects on lung cancer has not been reported. In this study, two polysaccharides (P31 and P32) were isolated from the aqueous extract of PV and purified through ethanol precipitation, followed by deproteination using DEAE-52 gel-filtration chromatography. The main monosaccharide composition of polysaccharide P32 was analyzed by GC. It was found that polysaccharide P32 consisted of rhamnose, arabinose, xylose, mannose, glucose and galactose in a molar ratio of 3.46:49.32:58.91:0.43:2.64: 3.11, respectively. In order to evaluate polysaccharide P32’s anti-lung adenocarcinoma activities and immunomodulation effects, a C57BL/6 mouse-Lewis lung carcinoma (LLC) model was established and investigated. Our results showed that polysaccharides of PV had anti-lung cancer activity and could increase the thymus index and the spleen index in tumor-bearing mice, suggesting possible immunomodulation effects.

Role of intestinal hydrolase in the absorption of prenylated flavonoids present in Yinyanghuo.

Purpose: Yinyanghuo (Herba Epimdii) is a traditional Chinese herb containing prenylated flavonoids as its active constituents. The aim of this study was to examine the significance of the intestinal hydrolysis of prenylated flavonoids by lactase phlorizin hydrolase (LPH), an enzyme at the brush border membrane of intestinal cells. Methods: A four-site perfused rat intestinal model was used. The concentration of the flavonoids of interest and their metabolites in different intestinal segements were analyzed by HPLC, and the apparent permeabilities were calculated. A lactase phlorizin hydrolase inhibitor (gluconolactone) was employed to investigate the mechanism of the intestinal absorption, and the metabolites of the four flavonoids were identified using LC/MS/MS. Results: Diglycosides (icariin) or triglycosides (epimedin A, epimedin B, and epimedin C) were hydrolyzed rapidly in duodenum and jejunum producing one or two metabolites, while a monoglycoside (baohuoside I) was absorbed directly. When co-perfused with glucono-lactone, both the hydrolysis of diglycosides and triglycosides were significantly inhibited, with inhibition rates for icariin (62%, 50%, 40%, 46%), epimedin A, (55%, 26%, 21%, 14%); epimedin B (42%, 40%, 74%, 22%), and epimedin C (42%, 40%, 52%, 35%) in duodenum, jejunum, ileum, and colon, respectively. Also the metabolites of icariin, epimedin A, epimedin B, and epimedin C were identified as baohuoside I (one of two), sagittatoside A, sagittatoside B, and 2″-O-rhamnosylicariside II, respectively. Conclusions: The results showed that lactase phlorizin hydrolase was a major determinant of the intestinal absorption of prenylated flavonoids present in Yinyanghuo.

Formulation and Evaluation of Celastrol-Loaded Liposomes

The main purpose of this study was to evaluate the intestinal absorption and the antineoplastic effect of the poorly water-soluble drug celastrol when liposomes were used as oral drug delivery system. Liposomes were prepared by the ethanol-injection method. An optimized liposome formulation composed of phospholipid, cholesterol and Tween-80 resulted in favorable encapsulation efficiency at 98.06 ± 0.94%. Homogeneous and stable particle size of 89.6 ± 7.3 nm and zeta potential of −(87.7 ± 5.8) mV were determined by laser particle size analyzer. Subsequently, the four-site perfusion rat intestinal model revealed that celastrol-loaded liposomes had improved effective permeability compared to the free drug in four intestinal segments (p < 0.05). Moreover, celastrol-loaded liposomes could also inhibit the tumor growth in C57BL/6 mice. These results suggest that liposomes could be a promising perioral carrier for celastrol.

Antioxidant Activities of Various Extracts from Artemisisa selengensis Turcz (LuHao)

The antioxidant activities of the various extracts and fractions from the herbs of Artemisia selegensis Turcz (AST) were investigated by in vitro and in vivo assays. FRAP, DPPH and ABTS assays were used to evaluate the antioxidant activities of the extracts/fractions in vitro. The effect of water extract (WE) in reducing oxidative stress in male mice was evaluated. Phenolic acid compounds contribute significantly to the antioxidant activity. From the results of three in vitro antioxidant assays, WE was found to have the highest antioxidant activity, and among the WE subfractions, the water soluble fraction has a significant antioxidant activity. The in vivo antioxidant assay results showed that high doses of WE significantly decrease the MDA level compared to normal diet and D-(+) galactose group (p < 0.05), and the SOD activity of mice given a high dose of WE was the highest. These in vitro and in vivo studies demonstrated that the extracts, especially the WE from AST, have significant antioxidant and free radical scavenging activities. In summary, we propose that AST could be potentially used as a rich source of natural antioxidants.

The Anti-Lung Cancer Activities of Steroidal Saponins of P. polyphylla Smith var. chinensis (Franch.) Hara through Enhanced Immunostimulation in Experimental Lewis Tumor-Bearing C57BL/6 Mice and Induction of Apoptosis in the A549 Cell Line

P. polyphylla Smith var. chinensis (Franch.) Hara (PPSCFH) has been used as medicinal Paris for the prevention and treatment of cancers in China for thousands of years. Its main components, steroidal saponins (PRS), have been confirmed to inhibit tumor growth. In the present study, the immunostimulation of PRS was investigated in Lewis bearing-C57BL/6 mice while the induction of apoptosis in A549 cells was also studied. The treatment with PRS (2.5, 5.0 and 7.5 mg/kg) significantly inhibited tumor, volume, and weight in the C57BL/6 mice. The rates of inhibition of PRS (at 2.5, 5.0 and 7.5 mg/kg) were 26.49 ± 17.30%, 40.32 ± 18.91% and 54.94 ± 16.48%, respectively. The spleen and thymus indexes were increased remarkably, while the levels of inflammatory cytokines including TNF-α, IL-8 and IL-10 in serum were decreased according to ELISA assays. For A549 cells, Hoechst 33342 staining and annexin V/PI by flow cytometry showed that PRS (0.25, 0.50 and 0.75 mg/mL) induced nuclear changes of A549 cells with DNA condensation and fragmentations of chromatin, as well as inducing apoptosis. Furthermore, PRS could also attenuate the over-generation of intracellular ROS. Western blotting analysis showed a significant decrease on the expressions of proinflammatory cytokines MCP-1, IL-6 and TGF-β1, as well as cell adhesion molecule ICAM-1, by treatment with PRS. Our results demonstrated that the inhibition of PRS on tumor growth might be associated with the amelioration of inflammation responses, induction of apoptosis, as well as the decrease of ROS. These results suggested that PRS implied a potential therapeutic effect in the lung cancer treatment.

Interaction of the main components from the traditional Chinese drug pair Chaihu-Shaoyao based on rat intestinal absorption.

The Chaihu-Shaoyao drug pair (Bupleuri Radix and Paeoniae Radix Alba) which is a traditional Chinese drug pair, has been widely used for anti-inflammatory purposes. Saikosaponin a (SSA), saikosaponin d (SSD) and paeoniflorin are identified as the main components in the pair. The present study focused on the interaction of the main components based on investigating their intestinal absorption using a four-site perfused rat intestinal model in order to clarify the mechanism of the compatibility of Chaihu-Shaoyao. The concentrations of SSA, SSD and paeoniflorin in the intestinal perfusate were determined by LC/MS or UPLC (Ultra Performance Liquid Chromatography) methods, followed by P*eff (effective permeability) and 10% ABS (the percent absorption of 10 cm of intestine) calculations. The results showed that all of the three main components displayed very low permeabilities (P*eff < 0.4), which implied their poor absorption in the rat intestine. The absorption levels of SSA and SSD were similar in intestine and higher in ileum than those in other intestinal regions in the decreasing order: colon, jejunum and duodenum. However, there is no significant difference in the absorption of paeoniflorin in the four segments (P < 0.05). The P*eff values of paeoniflorin exhibited an almost 2.11-fold or 1.90-fold increase in ileum when it was co-administrated with SSA and SSD, as well as 2.42-, 2.18-fold increase in colon, respectively, whereas the absorptions of SSA and SSD were not influenced by paeoniflorin. In conclusion, SSA and SSD could promote the absorption of paeoniflorin. To some extent this might explain the nature of the compatibility mechanisms of composite formulae in TCMs.

Combination of active components enhances the efficacy of Prunella in prevention and treatment of lung cancer.

The efficacy of Prunella extracts in the prevention and treatment of lung cancer has been attributed to different components. In this study, an active components combination model hypothesis was proposed to explain the anti-tumor activity of Prunella. The efficacy of Prunella extracts from different regions was compared in vitro and in vivo, and the TNF-α activity in serum of tumor-bearing mice was also evaluated. High performance liquid chromatography (HPLC) was used to analyze the extracts and identify 26 common peaks. Prunella samples from different regions were classified by the cluster analysis method; both P. vulgaris L. from Bozhou and P. asiatica Nakai from Nanjing, which had the highest activities, were further divided into different classes. Six peaks from the HPLC analysis were very similar, and were identified as caffeic acid, rosmarinic acid, rutin, quercetin, oleanolic acid and ursolic acid. The total ratio of these compounds in Prunella from Bozhou and Nanjing were 1.0:14.7:3.9:1.0:4.4:1.4 and 1.0:14.8:4.0:0.8:5.6:1.8, respectively. Total triterpenes and total phenols in Prunella were separated by macroporous resin purification for activity studies. The results showed that total triterpenes and total phenols had anti-lung cancer activity and their combination significantly enhanced the activity. In addition, the combination also significantly increased the TNF-α content compared to total triterpenes or total phenols. The results indicated that the efficacy of Prunella against lung cancer was attributable to multiple components acting at an optimal ratio.

Hederagenin from the leaves of ivy (Hedera helix L.) induces apoptosis in human LoVo colon cells through the mitochondrial pathway

BackgroundColorectal cancer has become one of the leading cause of cancer morbidity and mortality throughout world. Hederagenin, a derivative of oleanolic acid isolated from the leaves of ivy (Hedera helix L.), has been shown to have potential anti-tumor activity. The study was conducted to evaluate whether hederagenin could induce apoptosis of human colon cancer LoVo cells and explore the possible mechanism.MethodsMTT assay was used for evaluating cell viability while Annexin V-FITC/PI assay and Hoechst 33342 nuclear stainining were used for the determination of apoptosis and mitochondrial membrane potential. DCFH-DA fluorescence staining and flow cytometry were used to measure ROS generation. Real-time PCR and western blot analysis were performed for apoptosis-related protein expressions.ResultsMTT assay showed that hederagenin could significantly inhibit the viability of LoVo cells in a concentration-dependent and time-dependent manner by IC50 of 1.39xa0μM at 24xa0h and 1.17xa0μM at 48xa0h. The apoptosis ratio was significantly increased to 32.46% and 81.78% by the induction of hederagenin (1 and 2xa0μM) in Annexin V-FITC/PI assay. Hederagenin could also induce the nuclear changes characteristic of apoptosis by Hoechst 33342 nuclear stainining under fluorescence microscopy. DCFH-DA fluorescence staining and flow cytometry showed that hederagenin could increase significantly ROS generation in LoVo cells. Real-time PCR showed that hederagenin induced the up-regulation of Bax and down-regulation of Bcl-2, Bcl-xL and Survivin. Western blotting analysis showed that hederagenin decreased the expressions of apoptosis-associated proteins Bcl-2, procaspase-9, procaspase-3, and polyADP- ribosepolymerase (PARP) were increased, while the expressions of Bax, caspase-3, caspase-9 were increased. However, there was no significant change on caspase-8.ConclusionsThese results indicated that the disruption of mitochondrial membrane potential might contribute to the apoptosis of hederagenin in LoVo cells. Our findings suggested that hederagenin might be a promising therapeutic candidate for human colon cancer.

The Pharmacokinetics of Raloxifene and Its Interaction with Apigenin in Rat

Purpose: Raloxifene is a selective estrogen receptor modulator which is structurally similar to tamoxifen. As flavonoids can interact with raloxifene in vitro, we evaluated the in vivo pharmacokinetics of raloxifene in rats when co-administered with apigenin. Methods: The pharmacokinetics of raloxifene in the absence or presence of apigenin was investigated in rats after different dosage regimens. The plasma concentrations before and after enzymatic hydrolysis were analyzed by HPLC, and the pharmacokinetic profiles of raloxifene administered alone and in combination with apigenin were compared. Results: Co-administration of apigenin with raloxifene in a 1:2 ratio by weight resulted in a 55% and 37% increase in the Cmax and AUC of intact raloxifene, respectively. When equal proportions of raloxifene and apigenin (1:1) were administered, the Cmax and AUC of intact raloxifene were increased by 173% and 97% respectively. This increase in intact raloxifene was not associated with an increase in total raloxifene (intact plus conjugated raloxifene) because AUC and Cmax of total raloxifene when administered alone or in combination with apigenin were found to be similar. The results indicated that apigenin inhibited the glucuronidation and sulfation of raloxifene in the intestine bringing about an increased bioavailability of the drug. Conclusions: The results showed that apigenin decreased the first-pass metabolism of raloxifene but did not increase its absorption from the gastrointestinal tract.

The Antiosteoporotic Activity of Central-Icaritin (CIT) on Bone Metabolism of Ovariectomized Rats

Central-icaritin (CIT) is a flavonoid aglycone first discovered in our laboratory, which is an isomeric aglycone of icaritin (IT). We wanted to know whether CIT also had anti-osteoporosis activity. In this study, CIT was investigated in an ovariectomized rat (OVX) model. Fifty-six 6-month old female Sprague-Dawley rats were randomly assigned to sham operated group (Sham) and six OVX subgroups (n = 8 each). The OVX rats were then subdivided into six groups treated with vehicle (OVX), icaritin (IT, 40 mg/kg body weight/day), estradiol valerate (EV, 100 μg/kg body weight/day) or CIT (10, 20, and 40 mg/kg body weight/day) for 12 weeks, respectively. Then, the serum biochemical parameters, bone mineral density (BMD), bone biomechanical properties, bone microarchitecture, bone immunohistochemistry and related protein and gene expressions were evaluated. In OVX rats, the increases of body weight, HOP, AKP, and TRACP5b levels, and the decreases of uterus wet weight, femurs weight, BMD, serum OPG/RANKL and OCN were significantly inhibited by CIT treatment. Micro-CT analysis results showed that CIT apparently enhanced trabecular bone compared with the OVX group (p < 0.05). Total femur BMD and biomechanical strength of tibia were significantly improved (p < 0.05) after 12 weeks of CIT administration. In addition, the CIT administration also significantly enhanced the OPG expression, whereas reduced the RANKL expression in femurs according to RT-PCR, western blot assays and immunohistochemical evaluation. CIT had the antiosteoporotic activity, and its antiosteoporotic effects in OVX rats may be stronger than that of IT.