HPLC-DAD fingerprints combined with chemometric techniques for the authentication of plucking seasons of Laoshan green tea.

Laoshan green teas plucked in summer and autumn were measured by high performance liquid chromatography-diode array detector (HPLC-DAD). After baseline correction, the fingerprints data were resolved by multivariate curve resolution-alternating least squares (MCR-ALS) and a total of 57 components were acquired. Relative concentrations of these components were afterwards applied to distinguish plucking seasons using principal component analysis (PCA), support vector machines (SVM) and partial least squares-discriminant analysis (PLS-DA). For both SVM and PLS-DA models, the total recognition rates of training set, cross-validation and testing set were 100%, 91.3% and 100%, respectively. Besides, three variable selection methods were employed to determine characteristic components for the authentication of summer and autumn teas. Results showed that PLS-DA model based on three characteristic components selected by VIP possesses identical predictive ability as the original model. This study demonstrated that our proposed strategy is competent for the authentication of plucking seasons of Laoshan green tea.

WITHAFERIN A INDUCES APOPTOSIS IN RAT C6 GLIOMA CELLS THROUGH REGULATING NF-KB NUCLEAR TRANSLOCATION AND ACTIVATION OF CASPASE CASCADE.

BACKGROUND: The demand for the chemopreventive drug from the plant source is increasing in recent times, owing to its various biological activities without any adverse effect. The intention of this current study was to examine the anti-glioma effect of Withaferin A (WFA) on C6 glioma cell line model. MATERIALS AND METHODS: C6 glioma cells were administrated with different concentration of WFA (50, 100, 200 and 500 µg/mL) and DMSO (control) group to examine its anti-proliferative, anti-inflammatory and pro-apoptotic activities. RESULTS: Treatment with WFA showed a significant decline in the glioma cell count in a dose-dependent manner and thus proving its anti-proliferative effect. Similarly, inflammatory markers were also substantially lowered upon treatment with different concentration of WFA. However, DNA fragmentation and apoptotic markers like Caspase-3 and 9 were concomitantly enhanced after co-cultured with different concentration of WFA and thus exhibiting its cytotoxicity efficacy. Furthermore, the protein expression of Bcl2 and Bax were markedly downregulated and upregulated respectively; upon treatment with WFA on C6 glioma cells. CONCLUSION: The outcome of this study evidently demonstrates that C6 glioma cells co-cultured with increased concentration of WFA, showed an anti-proliferative, anti-inflammatory and pro-apoptotic effect in a dose-dependent fashion.

ERK1/2 mediates glucose-regulated POMC gene expression in hypothalamic neurons.

Hypothalamic glucose-sensing neurons regulate the expression of genes encoding feeding-related neuropetides POMC, AgRP, and NPY - the key components governing metabolic homeostasis. AMP-activated protein kinase (AMPK) is postulated to be the molecular mediator relaying glucose signals to regulate the expression of these neuropeptides. Whether other signaling mediator(s) plays a role is not clear. In this study, we investigated the role of ERK1/2 using primary hypothalamic neurons as the model system. The primary neurons were differentiated from hypothalamic progenitor cells. The differentiated neurons possessed the characteristic neuronal cell morphology and expressed neuronal post-mitotic markers as well as leptin-regulated orexigenic POMC and anorexigenic AgRP/NPY genes. Treatment of cells with glucose dose-dependently increased POMC and decreased AgRP/NPY expression with a concurrent suppression of AMPK phosphorylation. In addition, glucose treatment dose-dependently increased the ERK1/2 phosphorylation. Blockade of ERK1/2 activity with its specific inhibitor PD98059 partially (approximately 50%) abolished glucose-induced POMC expression, but had little effect on AgRP/NPY expression. Conversely, blockade of AMPK activity with its specific inhibitor produced a partial (approximately 50%) reversion of low-glucose-suppressed POMC expression, but almost completely blunted the low-glucose-induced AgRP/NPY expression. The results indicate that ERK1/2 mediated POMC but not AgRP/NPY expression. Confirming the in vitro findings, i.c.v. administration of PD98059 in rats similarly attenuated glucose-induced POMC expression in the hypothalamus, but again had little effect on AgRP/NPY expression. The results are indicative of a novel role of ERK1/2 in glucose-regulated POMC expression and offer new mechanistic insights into hypothalamic glucose sensing.

Blood zinc, iron, and copper levels in critically ill neonates.

The aim of this study is to explore the prognostic value of blood zinc, iron, and copper levels in critically ill neonates by comparing blood metal levels with the score for neonatal acute physiology (SNAP). Forty-six neonates (26 boys, 20 girls; ages ranging from 10 min to 23 days) who had been admitted to the neonatal intensive care unit of hospital and who were critically ill according to SNAP were included. Another 15 neonates (12 boys, 8 girls; ages ranging from 30 min to 24 days) who were brought to the hospital for a health checkup were included as controls. Clinical data, time in the intensive care unit, prognosis, and SNAP for critically ill neonates were recorded. Blood Cu, Zn, and Fe values were measured by inductively coupled plasma atomic emission spectrophotometry. Ill neonates were divided into extremely critical (SNAP ≥ 10) and critical groups (1 ≤ SNAP < 9). Zn levels were lower in patients than in controls (p <0.05). Cu levels did not differ between patients and controls (p >0.05). Fe levels were not significantly between the critical and control groups (p >0.05). In ill neonates, blood Zn and Fe concentrations in the extremely critical group were lower than in the critical group (p <0.05). Serious illness in neonates may lead to decreased Zn and Fe blood concentrations. Zn and Fe supplements may be beneficial for critically ill children.

[Studies on screening of matrix and permeation enhancer of sustained-release patches of duliang].

OBJECTIVE: To screen the matrix and permeation enhancer of Duliang Patches. METHODS: Based on L9 (3(4)) orthogonal experimental design, the content of imperatorin of the release rate and transdermal osmolality were regarded as evaluation indexes to optimize the matrix and permeation enhancer of patches suing of Drug dissolution tester and Franz diffusion cell. RESULTS: The best prescriplion of sustained-release patch of Duliang was: the quality percentage content of the starch, sodium carboxymethyl cellulose, glycerin, azone, propylene glycol and PEG400 was 6%, 2%, 30%, 1%, 15% and 2.5% respectively. The release behavior of sustained-release patches of Duliang tallied with Higuchi equation and the effect of sustained-release was apparent. CONCLUSION: The sustained-release patches of Duliang have good property of sustained-release and transdermal in vitro and the stability of patches is also sound while the release in vivo awaits further inspection.

Contribution of neural cell death to depressive phenotypes of streptozotocin-induced diabetic mice.

Major depression disorder (MDD) or depression is highly prevalent in individuals with diabetes, and the depressive symptoms are more severe and less responsive to antidepressant therapies in these patients. The underlying mechanism is little understood. We hypothesized that the pathophysiology of comorbid depression was more complex than that proposed for MDD and that neural cell death played a role in the disease severity. To test this hypothesis, we generated streptozotocin (STZ)-induced diabetic mice. These mice had blood glucose levels threefold above controls and exhibited depressive phenotypes as judged by a battery of behavioral tests, thus confirming the comorbidity in mice. Immunohistological studies showed markedly increased TUNEL-positive cells in the frontal cortex and hippocampus of the comorbid mice, indicating apoptosis. This finding was supported by increased caspase-3 and decreased Bcl-2 proteins in these brain regions. In addition, the serum brain-derived neurotrophic factor (BDNF) level of comorbid mice was reduced compared with controls, further supporting the neurodegenerative change. Mechanistic analyses showed an increased expression of mitochondrial fission genes fission protein 1 (Fis1) and dynamin-related protein 1 (Drp1), and a decreased expression of mitochondrial fusion genes mitofusin 1 (Mfn1), mitofusin 2 (Mfn2) and optical atrophy 1 (Opa1). Representative assessment of the proteins Drp1 and Mfn2 mirrored the mRNA changes. The data demonstrated that neural cell death was associated with the depressive phenotype of comorbid mice and that a fission-dominant expression of genes and proteins mediating mitochondrial dynamics played a role in the hyperglycemia-induced cell death. The study provides new insight into the disease mechanism and could aid the development of novel therapeutics aimed at providing neuroprotection by modulating mitochondrial dynamics to treat comorbid depression with diabetes.

Gypenosides protects dopaminergic neurons in primary culture against MPP(+)-induced oxidative injury.

Oxidative injury has been implicated in the etiology of Parkinson's disease (PD). Gypenosides (GPs), the saponins extract derived from the Gynostemma pentaphyllum, has various bioactivities. In this study, GPs was investigated for its neuroprotective effects on the 1-methyl-4-phenylpyridinium ion (MPP(+))-induced oxidative injury of dopaminergic neurons in primary nigral culture. It was found that GPs pretreatment, cotreatment or posttreatment significantly and dose-dependently attenuated MPP(+)-induced oxidative damage, reduction of dopamine uptake, loss of tyrosine hydrolase (TH)-immunopositive neurons and degeneration of TH-immunopositive neurites. However, the preventive effect of GPs was more potential than its therapeutical effect. Most importantly, the neuroprotective effect of GPs may be attributed to GPs-induced strengthened antioxidation as manifested by significantly increased glutathione content and enhanced activity of glutathione peroxidase, catalyze and superoxide dismutase in nigral culture. The neuroprotective effects of GPs are specific for dopaminergic neurons and it may have therapeutic potential in the treatment of PD.

[Bi-axial flexure strength and fracture mode of alumina glass-infiltrated core/veneer ceramic composites].

PURPOSE: To determine the bi-axial flexural strength and fracture mode of bilayered alumina glass-infiltrated core and the veneering porcelain. METHODS: Forty disk specimens were made from alumina glass-infiltrated core (HSDC-A) and veneer porcelain (Vintage AL), and equally divided into four groups as follows: monolithic specimens of veneer(MV),monolithic specimens of core material(MC),bilayered specimens with the veneer on top (BC) and bilayered specimens with core material on top(BV). Mean flexure strength, standard deviation and associated Weibull modulus were determined using bi-axial flexure (ball-on-ring) for each group. The results were analyzed with one-way ANOVA and the Weibull distribution with SPSS 13.0 software package. Both optical and scanning electron microscopy were employed for identification of the fracture mode and origin. RESULTS: The strength in the group MC and BC were significantly stronger than that in the group MV and BV. The frequency of specimen delamination, Hertzian cone formation and sub-critical radial cracking in the bilayered discs were dependent on the surface loaded in tension. CONCLUSION: Material which lies on the bottom surface dictates the strength and fracture mode of the specimens. Supported by Shenzhen Municipal Technological Project (Grant No.200903082).

The intestinal permeability of neolignans from the seeds of Myristica fragrans in the Caco-2 cell monolayer model.

The intestinal permeability and transport of 10 neolignans isolated from MYRISTICA FRAGRANS were studied by using the Caco-2 cell monolayer model. The 10 neolignans were measured by HPLC. Transport parameters and permeability coefficients were then calculated and compared with those of the model compounds, propranolol and atenolol. Among the 10 neolignans, the 8- O-4'-type neolignans demonstrated high permeability while the benzofuran-type neolignans were of poor to moderate permeability. Among them, eight neolignans were transported mainly VIA passive diffusion. These findings indicate that the 8- O-4'-type neolignans are well-absorbed compounds and can be used as oral leading compounds in drug discovery.

Intestinal permeability of antitumor alkaloids from the processed seeds of Strychnos nux-vomica in a Caco-2 cell model.

The uptake and intestinal permeability of the seven alkaloids strychnine (Str), brucine (Bru), beta-colubrine (Col), strychnine N-oxide (S-N), brucine N-oxide (B-N), pseudostrychnine (Psd), and icajine (Ica), which were isolated from the processed seeds of Strychnos nux-vomica L., were investigated in the human intestinal Caco-2 model. Determination of compounds was carried out by HPLC. The apparent permeability coefficients ( P(app)) for Str, Bru, Col, S-N, B-N, Psd, and Ica in the apical-to-basolateral direction were (3.11 +/- 0.17) x 10(-5), (1.67 +/- 0.65) x 10(-5), (2.67 +/- 0.30) x 10(-5), (0.17 +/- 0.01) x 10(-5), (0.35 +/- 0.02) x 10(-5), (2.51 +/- 0.33) x 10(-5), and (2.61 +/- 0.34) x 10(-5) cm/s, respectively. In the concentration range of 10-200 microM, Str, Bru, Col, and Psd showed substantial concentration-dependent transport across the monolayers. The transports of all seven alkaloids were linear with time and showed moderate to high permeabilities. In the presence of 2,4-dinitrophenol or sodium azide, the P(app) of Ica was reduced significantly in both the apical-to-basolateral and basolateral-to-apical directions. The dominant mechanism of the intestinal absorption for Str, Bru, Col, S-N, B-N, and Psd was passive diffusion, while it was partially ATP dependent for Ica.

[Absorption of papaverine, laudanosine and cepharanthine across human intestine by using human Caco-2 cells monolayers model].

Absorption of papaverine (PAP), laudanosine (LAU) and cepharanthine (CEP) as some chemical constituents of traditional Chinese medicines in human intestine were studied. By using Caco-2 (the human colonic adenocarcinoma cell lines) cell monolayers as an intestinal epithelial cell model, the permeability of PAP, LAU and CEP were studied from apical side (AP side) to basolateral side (BL side) or from BL side to AP side. The three alkaloids were measured by reversed-phase high-performance liquid chromatography coupled with UV detector. Transport parameters and apparent permeability coefficients (Papp) were then calculated and compared with those of propranolol as a control substance of high permeability and atenolol as a control substance of poor permeability. The Papp values of PAP, LAU and CEP were (3.524+/-0.223) x 10(-5), (2.821+/-0.050) x 10(-5) and (6.524+/-0.052) x 10(-5) cm s(-1) from AP side to BL side, and (5.095+/-0.508) x 10(-5), (2.646+/-0.146) x 10(-5) and (5.495+/-0.036) x 10(-5) cm s(-1) from BL side to AP side, respectively. Their Papp values were identical with those of propranolol, which is a transcellular transport marker. On the other hand, the efflux transport of PAP was 1.45 times higher than its influx transport with 0.69 rate of P(app A-->B)/P(app B-->A). But P(app A-->B)/P(app B-->A) values of LAU and CEP were 1.07 and 1.19, respectively, which suggested that the efflux transport have not been involved in their absorbed mechanism in Caco-2 cells monolayers. There is a good correlation between the Papp value and apparent distribution coefficient (Log D) at pH 7.35 for the three alkaloids. PAP, LAU and CEP can be absorbed across intestinal epithelial cells, and they are completely absorbed compounds. PAP may have been involved in efflux mechanism in Caco-2 cells monolayers model from the basolateral-to-apical direction. The O/W (oil/water) partition coefficient plays key role in their transmembrane permeation.

[Studies on predict of absorption of corynanthine, yohimbine, ajmalicine and ajmaline across human intestinal epithelial by using human Caco-2 cells monolayers].

OBJECTIVE: To predict the absorption of corynanthine (COR), yohimbine (YOH), ajmalicine (AMC) and ajmaline (AML) as chemical constituents of some traditional Chinese medicines in human intestinal epithelial. METHOD: By using Caco-2 (the human colonic adenocarcinoma cell lines) cell monolayers as a human intestinal epithelial cell model, the permeability of COR, YOH, AMC and AML were studied from apical side (AP side) to basolateral side (BL side) or from BL side to AP side. The four alkaloids were measured by high performance liquid chromatography (HPLC) coupled with UV detector. Transport parameters and apty) and atenolol (a control substance of poor permeability). The relationship between P(app) and log D values of four alkaloids was investigated by using drugs ADMET predict software. RESULT: The P(app) values of COR, YOH, AMC and AML were (1.863 +/- 0.055) x 10(-5), (1.540 +/- 0.082) x 10(-5), (2.522 +/- 0.246) x 10(-5) and (1.155 +/- 0.099) x 10(-5) cm x s(-1) from AP side to BL side, and (2.390 +/- 0.017) x 10(-5), (1.987 +/- 0.154) x 10(-5), (1.374 +/- 0.260) x 10(-5) and (2.418 +/- 0.124) x 10(-5) cm x s(-1) from BL side to AP side, respectively, which P(app) values were identical with that of propranolol [(2.23 +/- 0.10) x 10(-5) cm x s(-1) from AP to BL side]. The ratio of P(app B --> A)/P(app A -->B) of COR, YOH, AMC and AML were 1.28, 1.29, 0.54 and 2.09, respectively, which suggested that the efflux transport of AML was 2.09 times higher more than its influx transport. CONCLUSION: COR, YOH, AMC and AML can be transported and absorbed across the human Caco-2 cells monolayers, and they belong to completely absorbed compounds. AML may have been involved in efflux mechanism in Caco-2 cells monolayers model from the BL to AP side direction. The oil-water partition coefficient play key roles in the transport and absorption of the four alkaloids.

[Establishment of Caco-2 cell monolayer model and standard operation procedure for assessing intestinal absorption of chemical components of traditional Chinese medicine].

OBJECTIVE: To establish Caco-2 (a human colon adenocarcinoma cell line) cell monolayer model and the standard operation procedure for studying and assessing intestinal absorption of chemical components of traditional Chinese medicine. METHODS: Caco-2 cell monolayer model was established and evaluated by morphology feature using scanning electron microscope, inverted microscope and transepithelial electrical resistance (TEER) assay. Additionally, the model was further tested for the activity of alkaline phosphatase and the apparent permeability (Papp) of standard compounds, i.e. propranolol and atenolol, which were the control substances for high and poor transcellular transport marker, respectively. RESULTS: The integrality of cell monolayer, cell differentiation (reflected by expression of alkaline phosphatase and cell monolayer morphology), and the Papp value of standard compounds in the established Caco-2 cell model were satisfactory. All parameters tested were in good agreement with those reported in the literature. CONCLUSION: The established Caco-2 cell model can be used to study the intestinal absorption of orally administrated chemical components of traditional Chinese medicine and their absorption mechanism.

[Absorption of coptisine chloride and berberrubine across human intestinal epithelial by using human Caco-2 cell monolayers].

OBJECTIVE: To study the absorption of coptisine chloride (COP) and berberrubine (BRB) as chemical constituents of some traditional Chinese medicines in human intestinal epithelial. METHOD: By using Caco-2 (the human colonic adenocarcinoma cell lines) cell monolayers as an intestinal epithelial cell model, the permeability of COP and BRB were studied from apical side (AP side) to basolateral side (BL side) or from BL side to AP side. The two alkaloids were measured by reversed-phase high performance liquid chromatography (HPLC) coupled with UV detector. Transport parameters and apparent permeability coefficients (P(app)) were then calculated and compared with those of propranolol and atenolol. P(app) values were also compared with the reported values for model compounds (propranolol and atenolol). RESULT: The P(app) values of COP, BRB were (1.103 +/- 0.162) x 10(-5), (1.309 +/- 0.102) x 10(-5) cm x s(-1 from AP side to BL side, and (0.300 +/- 0.041) x 10(-5) and (1.955 +/- 0.055) x 10(-5) cm x s(-1) from BL side to AP side, respectively. Their P(app) values were identical with those of propranolol [(2.23 +/- 0.10) x 10(-5 cm x s(-1)], which is a transcellular transport marker and as a control substance for high permeability. On the other hand, the efflux transport of BRB was higher 1.49 times more than its influx transport with 0.67 rate of P(app A-->B)/P(app B-->A). But P(app A-->B)/P(app B-->A value of COP was 3.67, which suggested that the efflux transport have not been involved in its absorbed mechanism in Caco-2 cells monolayers. CONCLUSION: COP and BRB can be absorbed across intestinal epithelial cells, and they are completely absorbed compounds. BRB may have been involved in efflux mechanism in Caco-2 cells monolayers model from the basolateral-to-apical direction.

Bone marrow stromal cells express neural phenotypes in vitro and migrate in brain after transplantation in vivo.

OBJECTIVE: To investigate the differentiation of bone marrow stromal cells (BMSC) into neuron-like cells and to explore their potential use for neural transplantation. METHODS: BMSC from rats and adult humans were cultured in serum-containing media. Salvia miltiorrhiza was used to induce human BMSC (hBMSC) to differentiate. BMSC were identified with immunocytochemistry. Semi-quantitative RT-PCR was used to examine mRNA expression of neurofilamentl (NF1), nestin and neuron-specific enolase (NSE) in rat BMSC (rBMSC). Rat BMSC labelled by Hoschst33258 were transplanted into striatum of rats to trace migration and distribution. RESULTS: rBMSC expressed NSE, NF1 and nestin mRNA, and NF1 mRNA and expression was increased with induction of Salvia miltiorrhiza. A small number of hBMSC were stained by anti-nestin, anti-GFAP and anti-S100. Salvia miltiorrhiza could induce hBMSC to differentiate into neuron-like cells. Some differentiated neuron-like cells, that expressed NSE, beta-tubulin and NF-200, showed typical neuron morphology, but some neuron-like cells also expressed alpha smooth muscle protein, making their neuron identification complicated. rBMSC could migrate and adapted in the host brains after being transplanted. CONCLUSION: Bone marrow stromal cells could express phenotypes of neurons, and Salvia miltiorrhiza could induce hBMSC to differentiate into neuron-like cells. If BMSC could be converted into neurons instead of mesenchymal derivatives, they would be an abundant and accessible cellular source to treat a variety of neurological diseases.

Effect of jianpiyiwei capsule on gastric precancerous lesions in rats.

AIM: To evaluate the therapeutic effect of compound Chinese drugs, Jianpiyiwei capsule (JPYW) on gastric precancerous lesions in rats and to explore its mechanism of action. METHODS: Model of gastric precancerous lesions was constructed in male Wistar rats: a metal spring was inserted and fixed through pyloric sphincter. One week after recovery, each rat was given 50-60 degrees hot paste containing 150 g/L NaCl 2 mL orally, twice a week for 15 weeks. Then 10 normal and 11 model rats were anaesthetized, after the measurement of gastric mucosa blood flow (GMBF), the rats were killed and the mucosal hexosamines and malonic dialdehyde (MDA) were measured. The morphological changes of gastric mucosa were observed macroscopically and microscopically, and by an automatic imaging analysis system. Other rats were treated with JPYW 1.5 g/kg.d(-1) or 4.5 g/kg.d(-1), or distilled water as negative control respectively (n=10 in each group). After 12 weeks, all the rats were examined as above. RESULTS: The gastric mucosa of model rats showed chronic atrophic gastritis with dysplasia and intestinal metaplasia (IM), GMBF and hexosamine content were reduced significantly and MDA was increased as compared to the normal group (P<0.01). After 12 weeks treatment, the pathological changes of the negative control group became worsened, while in JPYW treated groups the changes were modified with significant increase of GMBF and reduction of MDA, although the hexosamine concentration increased only mildly. CONCLUSION: JPYW increases GMBF and reduces MDA content in gastric mucosa and has therapeutic effects on gastric precancerous lesions.