Chaomei Xiong

Extraction and determination of some psychotropic drugs in urine samples using dispersive liquid-liquid microextraction followed by high-performance liquid chromatography.

A simple, rapid and sensitive method termed as dispersive liquid-liquid microextraction (DLLME) combined with high-performance liquid chromatography-ultraviolet detector (HPLC-UV) has been proposed for the determination of three psychotropic drugs (amitryptiline, clomipramine and thioridazine) in urine samples. The determination was performed on a C(8) column under the optimal chromatographic conditions (mobile phase: ammonium acetate (0.03 mol L(-1), pH 5.5)-acetonitrile (60:40, v/v); flow rate: 1.0 mL min(-1); detection wavelength: 238 nm). Several factors influencing the extraction efficiency of the target drugs, such as pH, extraction and disperser solvent type and their volume, extraction time and ion strength were studied and optimized. Under the optimal DLLME conditions, the absolute recoveries of amitryptiline, clomipramine and thioridazine from the urine samples were 96, 97 and 101%, respectively. The detection limits (LODs) and quantification (LOQs) of the proposed approach were 3 and 10 ng mL(-1) for amitryptiline, 7 and 21 ng mL(-1) for clomipramine, and 8 and 25 ng mL(-1) for thioridazine, respectively. The relative standard deviations (RSDs) for nine replicate determinations at 0.100 microg mL(-1) level of target drugs were less than 4.8%. Good linear behaviors over the investigated concentration ranges were obtained with the values of R(2)>0.998 for the target drugs. The proposed method was successfully applied to the real urine samples from two female patients under amitryptiline and clomipramine treatment, respectively.

Apoptosis induced by a new flavonoid in human hepatoma HepG2 cells involves reactive oxygen species-mediated mitochondrial dysfunction and MAPK activation.

Earlier reports suggest that protoapigenone showed remarkable anticancer activities. In the present study, the cytotoxic effect of a new flavonoid, 2-(cis-1, 2-dihydroxy 4-oxo-cyclohex-5-enyl)-5, 7-dihydroxy-chromone (DEDC), which is a protoapigenone analog, was investigated in human hepatoma HepG2 cells. We found that hepatoma cells were highly susceptible to DEDC in contrast with normal cells. The sustainable and rapid generation of reactive oxygen species was observed in DEDC-induced cell death. Following oxidative stress, DEDC sequentially decreased mitochondrial membrane potential (ΔΨm), reduced Bcl-2 expression, increased cytochrome c release, and activated caspase-3, -8, and -9. Phosphorylation of c-Jun N-terminal kinase (JNK) and p38 mitogen activated protein kinase (MAPK) was stimulated by treatment with DEDC. To further investigate the mechanisms of the DEDC-induced cell death, we examined the effects of reactive oxygen species scavenger N-acetyl-L-cysteine (NAC) and selective inhibitors for MAPK pathways on the cell death. The DEDC-induced cell death was significantly inhibited by both NAC and JNK inhibitor SP600125, but promoted by p38 MAPK inhibitor, SB203580. Together, DEDC may have antitumor effects in HepG2 cells through reactive oxygen species production as well as activation of MAPK signaling pathways.

Hypolipidemic and anti-inflammatory properties of Abacopterin A from Abacopteris penangiana in high-fat diet-induced hyperlipidemia mice.

This study was to investigate the hypolipidemic and anti-inflammatory properties of Abacopterin A (APA), a flavonoid compound isolated from Abacopteris penangiana (Hook.) Ching. Male C57BL/6J mice were divided randomly and equally into five groups: the normal control group (N), the model group (M), the positive control group (P), the high and low doses of APA treated groups (H and L). All the animals except that in N group were fed with high-fat diet for 8 weeks. In the last 4 weeks, the mice in P, H and L groups were orally administered with simvastatin (at the dose of 20mg/kg/day) and APA (at the dose of 40 or 20mg/kg/day), respectively. Then the lipid profiles and related biochemical criterions of the studied mice were determined. The effects of high-fat diet on activating nuclear transcription factor-κB (NFκB) expression, elevating inflammatory factors tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6) levels, and increasing triacylglycerol (TG) and total cholesterol (TC) levels were abolished on daily supplementation with APA. APA also enhanced lipoprotein lipase (LPL) and hepatic lipase (HL) activities. These results suggested that APA had hypolipidemic and anti-inflammatory properties through inhibiting NFκB expression, and reducing inflammatory response.

DEDC, a new flavonoid induces apoptosis via a ROS-dependent mechanism in human neuroblastoma SH-SY5Y cells.

The poor prognosis of neuroblastoma and lack of effective remedies have necessitated the application of new therapeutic scheme. Over the past few years, it has been found that flavonoids could exert specific cytotoxic activity towards cancer cells. 2-(cis-1,2-dihydroxy-4-oxo-cyclohex-5-enyl)-5,7-dihydroxy-chromone (DEDC) is a plant-derived flavonoid extracted from the aerial part of Macrothelypteris torresiana. The present study investigated the cytotoxic effects and underlying biochemical pathway leading to cell death on the response of DEDC treatment in human neuroblastoma cells. Our results indicated that (a) DEDC induced SH-SY5Y cells apoptosis by elevating reactive oxygen species (ROS) generation, and ROS generation that could be quenched by the antioxidants N-acetyl cystein (NAC). (b) The signal transducer and activator of transcription 3 (STAT3) played a crucial role in DEDC-triggered cell death. (c) Nuclear factor Kappa B (NF-κB) was activated following exposure to DEDC, and suppressing NF-κB pathway by pyrrolidine dithiocarbamate (PDTC, a potent NF-κB inhibitor) significantly increased neuroblastoma cell sensitivity to the pro-apoptotic effect of DEDC. Overall, this study shed light on the mechanism of action of DEDC and suggested more rational approaches to investigation and therapy for this childhood malignancy.

Abacopteris penangiana exerts testosterone-induced benign prostatic hyperplasia protective effect through regulating inflammatory responses, reducing oxidative stress and anti-proliferative.

ETHNOPHARMACOLOGICAL RELEVANCE Abacopteris penangiana (Hook.) Ching (AP) is a member of parathelypteris glanduligera and used in folk medicine for the treatment of blood circulation and blood stasis, edema and inflammation as recorded in the ″Chinese Materia Medica″. AIM OF THE STUDY The purpose of this study was to investigate the effects of total flavanol glycosides (TFA) from AP and its acid hydrolysate (AHT) on testosterone-induced benign prostatic hyperplasia (BPH) in rats by measuring the levels of inflammatory responses, oxidative stress and prostate cell proliferation. MATERIALS AND METHODS BPH was induced in rats by subcutaneous injection of testosterone after castration. Seventy rats were divided into seven groups. After oral administration of AHT and TFA (100 or 200mg/kg/d) for 4 weeks, the prostate index (PI), 5a-reductase (5α-R) and dihydrotestosterone (DHT) were determined. Then the activities of superoxide dismutase (SOD), glutathione peroxidase (GPx) and catalase (CAT) were determined. In addition, the relative inflammatory factors, cyclooxygenase-2 (COX-2), tumor necrosis factor-α (TNF-α), interleukin 1β (IL-1β), interleukin 6 (IL-6), interleukin 8 (IL-8) and interleukin 17 (IL-17) were measured. Finally, the prostatic expression of nuclear transcription factor-κB (NF-κB) and phosphoinositide3-kinase (PI3K)/Akt were determined by immunohistochemistry. The prostatic expression of Bcl-2 was determined by western blot analysis. RESULTS The results showed that AHT and TFA decreased serum DHT and 5α-R activities compared with model group, as well as the PI and histopathological examination findings. In addition, oral treatment of AHT and TFA can significantly increase the activities of SOD, GPx and CAT while the level of MDA was significantly decreased compared with the model group. Moreover, AHT and TFA remarkably decreased the levels of inflammatory cytokines in prostatic tissue. Further investigation demonstrated that AHT and TFA treatment down-regulated the protein expressions of p-Akt, NF-κB and Bcl-2. CONCLUSIONS These results suggest that AHT and TFA have anti-BPH properties via anti-inflammatory, antioxidant and anti-proliferative effects. Hence, AP represents a potential herb for the treatment of BPH.

A novel compound RY10-4 induces apoptosis and inhibits invasion via inhibiting STAT3 through ERK-, p38-dependent pathways in human lung adenocarcinoma A549 cells

Previous reports suggested that protoapigenone showed remarkable antitumor activities against a broad spectrum of human cancer cell lines, but had no effect on human lung adenocarcinoma A549 cell. The lack of effective remedies had necessitated the application of new therapeutic scheme. A novel compound RY10-4 which has the similar structure close to protoapigenone showed better antitumor activity. Treatment with RY10-4 inhibited the expression of pro-caspase-3, pro-caspase-9, Bcl-2 as well as phosphorylation of signal transducer and activator of transcription-3 (p-STAT3). It also reduced the expressions of matrix metalloproteinase-2 (MMP-2), matrix metalloproteinase-9 (MMP-9) and increases the expressions of reversion-inducing cysteine-rich protein with kazal motifs (RECK), as well as tissue inhibitor of metalloproteinase (TIMP) via inhibiting STAT3 by activating the mitogen-activated protein (MAP) kinases (the c-Jun N-terminal kinase (JNK), the p38 and extracellular signal-regulated kinase (ERK)) in A549 cells treated with RY10-4. Moreover, the cytotoxic effect of RY10-4 was induction of apoptosis in A549 cells by enhancing production of reactive oxygen species (ROS). Taken together, the observations suggested that RY10-4 had affected Bcl-2 family members, caspases, MMPs, TIMPs expressions and ROS production via inhibiting STAT3 activities through ERK and p38 pathways in A549 cells.

Dioscin-induced apoptosis of human LNCaP prostate carcinoma cells through activation of caspase-3 and modulation of Bcl-2 protein family

SummaryDioscin is a natural steroid saponin derived from several plants, showing potent anti-cancer effect against a variety of tumor cell lines. In the present study, we investigated the anti-cancer activity of dioscin against human LNCaP cells, and evaluated the possible mechanism involved in its antineoplastic action. It was found that dioscin (1, 2 and 4 μmol/L) could significantly inhibit the viability of LNCaP cells in a time- and concentration-dependent manner. Flow cytometry revealed that the apoptosis rate was increased after treatment of LNCaP cells with dioscin for 24 h, indicating that apoptosis was an important mechanism by which dioscin inhibited cancer. Western blotting was employed to detect the expression of caspase-3, Bcl-2 and Bax in LNCaP cells. The expression of cleaved caspase-3 was significantly increased, and meanwhile procaspase-3 was markedly decreased. The expression of anti-apoptotic protein Bcl-2 was down-regulated, whereas the pro-apoptotic protein Bax was up-regulated. Moreover, the Bcl-2/Bax ratio was drastically decreased. These results suggested that dioscin possessed potential anti-tumor activity in human LNCaP cells through the apoptosis pathway, which might be associated with caspase-3 and Bcl-2 protein family.Dioscin is a natural steroid saponin derived from several plants, showing potent anti-cancer effect against a variety of tumor cell lines. In the present study, we investigated the anti-cancer activity of dioscin against human LNCaP cells, and evaluated the possible mechanism involved in its antineoplastic action. It was found that dioscin (1, 2 and 4 μmol/L) could significantly inhibit the viability of LNCaP cells in a time- and concentration-dependent manner. Flow cytometry revealed that the apoptosis rate was increased after treatment of LNCaP cells with dioscin for 24 h, indicating that apoptosis was an important mechanism by which dioscin inhibited cancer. Western blotting was employed to detect the expression of caspase-3, Bcl-2 and Bax in LNCaP cells. The expression of cleaved caspase-3 was significantly increased, and meanwhile procaspase-3 was markedly decreased. The expression of anti-apoptotic protein Bcl-2 was down-regulated, whereas the pro-apoptotic protein Bax was up-regulated. Moreover, the Bcl-2/Bax ratio was drastically decreased. These results suggested that dioscin possessed potential anti-tumor activity in human LNCaP cells through the apoptosis pathway, which might be associated with caspase-3 and Bcl-2 protein family.

Anti-tumor and anti-angiogenic effects of Macrothelypteris viridifrons and its constituents by HPLC–DAD/MS analysis

ETHNOPHARMACOLOGICAL RELEVANCE Macrothelypteris viridifrons is widely distributed in south of China and has been used as folk medicine to treat cancer, hydropsy, and traumatic bleeding. AIM OF THE STUDY To investigate the chemical constituents and the anti-tumor and anti-angiogenic effects of Macrothelypteris viridifrons. MATERIALS AND METHODS An HPLC-DAD/MS technique was used to determine the flavonoid profile of Macrothelypteris viridifrons. The anti-tumor effect of Macrothelypteris viridifrons was evaluated by in vivo mice bearing H22 hepatoma cells transplantation tumor model. And the anti-angiogenic activity was investigated by measuring the effects on the in vitro proliferation, migration, and tube formation of human umbilical vein endothelial cells (HUVECs). Furthermore, the in vivo zebrafish model was applied to evaluate the anti-angiogenic effect of Macrothelypteris viridifrons. RESULTS 18 flavonoids were identified from Macrothelypteris viridifrons. Administration of Macrothelypteris viridifrons significantly inhibited the tumor growth and the expression of vascular endothelial growth factor (VEGF) and CD34. Meanwhile, Macrothelypteris viridifrons showed significant inhibition on proliferation, migration and tube formation of HUVECs in vitro and the intersegmental vessels formation in zebrafish model. CONCLUSIONS Macrothelypteris viridifrons showed significant anti-tumor and anti-angiogenic effects and might be developed as a novel anti-tumor drug.

Dispersive liquid-liquid microextraction combined with high-performance liquid chromatography for the determination of clozapine and chlorpromazine in urine

SummaryA simple method has been proposed for the determination of clozapine (CLZ) and chlorpromazine (CPZ) in human urine by dispersive liquid-liquid microextraction (DLLME) in combination with high-performance liquid chromatography-ultraviolet detector (HPLC-UV). All important variables influencing the extraction efficiency, such as pH, types of the extraction solvent and the disperser solvent and their volume, ionic strength and centrifugation time were investigated and optimized. Under the optimal conditions, the limit of detection (LODs) and quantification (LOQs) of the method were 13 and 39 ng/mL for CLZ, and 2 and 6 ng/mL for CPZ, respectively. The relative standard deviations (RSDs) of the targets were less than 5.1% (C=0.100 μg/mL, n=9). Good linear behaviors over the tested concentration ranges were obtained with the values of R2>0.999 for the targets. The absolute extraction efficiencies of CLZ and CPZ from the spiked blank urine samples were 98.3% and 97.8%, respectively. The applicability of the technique was validated by analyzing urine samples and the mean recoveries for spiked urine samples ranged from 93.3% to 105.0%. The method was successfully applied for the determination of CLZ and CPZ in real human urine.A simple method has been proposed for the determination of clozapine (CLZ) and chlorpromazine (CPZ) in human urine by dispersive liquid-liquid microextraction (DLLME) in combination with high-performance liquid chromatography-ultraviolet detector (HPLC-UV). All important variables influencing the extraction efficiency, such as pH, types of the extraction solvent and the disperser solvent and their volume, ionic strength and centrifugation time were investigated and optimized. Under the optimal conditions, the limit of detection (LODs) and quantification (LOQs) of the method were 13 and 39 ng/mL for CLZ, and 2 and 6 ng/mL for CPZ, respectively. The relative standard deviations (RSDs) of the targets were less than 5.1% (C=0.100 μg/mL, n=9). Good linear behaviors over the tested concentration ranges were obtained with the values of R 2>0.999 for the targets. The absolute extraction efficiencies of CLZ and CPZ from the spiked blank urine samples were 98.3% and 97.8%, respectively. The applicability of the technique was validated by analyzing urine samples and the mean recoveries for spiked urine samples ranged from 93.3% to 105.0%. The method was successfully applied for the determination of CLZ and CPZ in real human urine.

Neuroprotective effects of Abacopterin E from Abacopteris penangiana against oxidative stress-induced neurotoxicity

AIM OF THE STUDY Abacopterin E (AE) was isolated from Abacopteris penangiana (Hook.) Ching. This study was to elucidate its neuroprotective effects against hydrogen peroxide (H(2)O(2)) induced oxidative damage in PC12 cells and d-galactose (d-Gal) induced neurotoxicity in mice brain. MATERIALS AND METHODS In vitro, the protective effect of AE against H(2)O(2)-induced oxidative damage in the PC12 was investigated by the method of MTT (3,(4,5-dimethylthiazole-2-yl)2,5-diphenyl-tetrazolium bromide). In vivo, the protective effect of AE against d-Gal-induced neurotoxicity in mice was studied. The mice in the model group and the AE treatment groups were injected with the d-Gal 150 mg/(kg d) for 7 weeks while the mice in the control group were injected with the same volume of saline (0.9%). From the sixth week, the treatment groups were subcutaneously injected 4 or 8 mg/(kg d) of AE. In order to explore the potential mechanism of AEs action, the mice were assessed by behavioral and electrophysiological tests at the end of the administration. Then the mice brain tissues were measured for the levels of superoxide dismutases (SOD), glutathione peroxidase (GSH-Px), and malondialdehyde (MDA). RESULTS This study showed that AE lowered the H(2)O(2)-induced cytotoxicity, and AE significantly improved the learning and memory ability in behavioral performance. The biochemical examination revealed that AE restored the activities of SOD and GSH-Px, and attenuated the increase of MDA. Moreover, the electrophysiological analysis evidently showed that AE ameliorated the long-term potentiation (LTP). CONCLUSIONS These results suggested that AE had neuroprotective effects, and its beneficial effects may be linked with inhibiting the generation of free radical and enhancing the activities of endogenous antioxidant enzymes.