Pichia kurtzmaniana f.a. sp. nov., with the transfer of eight Candida species to Pichia.

Three yeast strains belonging to the ascomycetous yeast genus Pichia were isolated from two soil samples from Yunnan and Guizhou provinces and a marine water sample from Liaoning province, PR China. Phylogenetic analyses based on the sequences of the D1/D2 domains of the large subunit(LSU) rRNA gene and the internal transcribed spacer (ITS) region indicate that these three strains, together with 12 additional strains isolated from various substrates collected in different regions or countries of the world, represent a novel species of the genus Pichia, for which the name Pichia kurtzmaniana sp. nov. (holotype: strain CGMCC 2.7213) is proposed. The novel species differs from its close relatives Candida californica by eight (1.5 %) and 26 (11.1 %) mismatches in the D1/D2 domains and the ITS region, respectively; and from Pichia chibodasensis by 11 (2.1 %) and 20 (8.7 %) mismatches in the D1/D2 domains and the ITS region, respectively. In addition, eight Candida species which belong to the Pichia clade are transferred to the genus Pichia, resulting in the proposal of the following new combinations: Pichia cabralensis comb. nov., Pichia californica comb. nov., Pichia ethanolica comb. nov., Pichia inconspicua comb. nov., Pichia phayaonensis comb. nov., Pichia pseudolambica comb. nov., Pichia rugopelliculosa comb. nov., and Pichia thaimueangensis comb. nov.

Saturnispora sinensis sp. nov., a new ascomycetous yeast species from soil and rotten wood.

A yeast strain (CGMCC 2.6937T) belonging to the ascomycetous yeast genus Saturnispora was recently isolated from soil collected in Xinghuacun, Shanxi Province, PR China. The strain produces one or two ellipsoid or spherical ascospores in asci formed by the conjugation between a cell and its bud. Phylogenetic analyses of the internal transcribed spacer (ITS) region and the D1/D2 domain of the large subunit rRNA gene suggest that this strain is conspecific with strains NYNU 14639 isolated from rotten wood collected in Funiu Mountain, Henan province and ES13S05 from soil collected in Nantou County, Taiwan. The CGMCC 2.6937T group is most closely related to Saturnispora dispora and Saturnispora zaruensis. However, strain CGMCC 2.6937T differs from S. dispora by 17 (3.2 %, 13 substitutions and four gaps) and 77 (18.8 %, 52 substitutions and 25 gaps) mismatches, and from S. zaruensis by 15 (2.9 %, 12 substitutions and three gaps) and 64 (15.6 %, 44 substitutions and 20 gaps) mismatches, in the D1/D2 domain and ITS region, respectively. The results suggest that the CGMCC 2.6937T group represents an undescribed species in the genus Saturnispora, for which the name Saturnispora sinensis sp. nov. is proposed. The holotype strain is CGMCC 2.6937T.

Vishniacozyma pseudocarnescens sp. nov., a new anamorphic tremellomycetous yeast species.

Three strains belonging to the basidiomycetous yeast genus Vishniacozyma were isolated from marine water samples collected from intertidal zones in Liaoning province, northeast China. Phylogenetic analyses based on the sequences of the small subunit (SSU) ribosomal DNA (rDNA), the D1/D2 domain of the large subunit (LSU) ribosomal DNA (rDNA), the internal transcribed spacer region (ITS), the two subunits of DNA polymerase II (RPB1 and RPB2), the translation elongation factor 1-α (TEF1), and the mitochondrial gene cytochrome b (CYTB) showed that these strains together with 20 strains from various geographic and ecological origins from other regions of the world represent a novel species in the genus Vishniacozyma. We propose the name Vishniacozyma pseudocarnescens sp. nov. (holotype CGMCC 2.6457) for the new species, which differs phenotypically from its close relatives V. carnescens, V. tephrensis, and V. victoriae by its ability to grow at 30 °C and on 50 % (w/v) glucose-yeast extract agar.

Microbial communities and their correlation with flavor compound formation during the mechanized production of light-flavor Baijiu.

Light-flavor Baijiu fermentation is a typical spontaneous solid-state fermentation process fueled by a variety of microorganisms. Mechanized processes have been increasingly employed in Baijiu production to replace traditional manual operation processes, however, the microbiological and physicochemical dynamics in mechanized processes remain largely unknown. Here, we investigated the microbial community succession and flavor compound formation during a whole mechanized fermentation process of light-flavor Baijiu using the conventional dilution plating method, PacBio single-molecule real-time (SMRT) sequencing and headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry. The results showed that largely different fungal and bacterial communities were involved in the soaking and fermentation processes. A clear succession from Pantoea agglomerans to Bacillus (B.) smithii and B. coagulans in dominant bacterial species and from Cladosporium exasperatum to Saccharomyces cerevisiae and Lichtheimia ramosa in dominant fungal species occurred in the soaking processes. In the fermentation process, the most dominant bacterial species was shifted from Pantoea agglomerans to Lactobacillus (La.) acetotolerans and the most dominant fungal species were shifted from Lichtheimia ramose and Rhizopus arrhizus to Saccharomyces cerevisiae. The bacterial and fungal species positively associated with acidity and the formation of ethanol and different flavor compounds were specified. The microbial species exhibited strong co-occurrence or co-exclusion relationships were also identified. The results are helpful for the improvement of mechanized fermentation process of light-flavor Baijiu production.

Microbial Community Affects Daqu Quality and the Production of Ethanol and Flavor Compounds in Baijiu Fermentation.

Daqu is a traditional starter for Baijiu fermentation and is produced by spontaneous fermentation of ground and moistened barley or wheat. The quality of Daqu is traditionally evaluated based on physicochemical and subjective sensory parameters without microbiological analysis. Here, we compared the physicochemical characteristics of qualified (QD) and inferior (ID) Daqu, their microbial communities based on plate counting and PacBio SMRT sequencing of rRNA gene libraries, and their impacts on Baijiu fermentation. The results showed that the glucoamylase and α-amylase activities of QD were significantly higher than those of ID. The counts of yeasts and relative abundances of functional microbes, especially the amylolytic bacterium Bacillus licheniformis and fungi Saccharomycopsis fibuligera and Lichtheimia ramosa, were significantly higher in QD than in ID. The laboratory-scale Baijiu fermentation tests showed that the relative abundances of the amylolytic microbes were higher in the QD than the ID fermentation set, resulting in more efficient fermentation, as indicated by more weight loss and higher moisture content in the former. Consequently, more glycerol, acetic acid, ethanol, and other volatile compounds were produced in the QD than in the ID fermentation set. The results suggest that Daqu quality is determined by, and can be evaluated based on, its microbial community.

Role of micronutrients in Alzheimer's disease: Review of available evidence.

Alzheimer's disease (AD) is one of the most common age-related neurodegenerative disorders that have been studied for more than 100 years. Although an increased level of amyloid precursor protein is considered a key contributor to the development of AD, the exact pathogenic mechanism remains known. Multiple factors are related to AD, such as genetic factors, aging, lifestyle, and nutrients. Both epidemiological and clinical evidence has shown that the levels of micronutrients, such as copper, zinc, and iron, are closely related to the development of AD. In this review, we summarize the roles of eight micronutrients, including copper, zinc, iron, selenium, silicon, manganese, arsenic, and vitamin D in AD based on recently published studies.

Effect of green flickering light on myopia development and expression of M1 muscarinic acetylcholine receptor in guinea pigs.

AIM: To investigate the effects of green flickering light on refractive development and expression of muscarinic acetylcholine receptor (mAChR) M1 in the eyes of guinea pigs. METHODS: Thirty guinea pigs (15-20 days old) were randomly divided into three groups (n=10/group). Animals in group I were raised in a completely closed carton with green flickering light illumination. Those in group II were kept in the open top closed carton under normal natural light. Guinea pigs were raised in a sight-widen cage under normal natural light in group III. The refractive status and axial length were measured before and after 8 weeks' illumination. Moreover, total RNA extracted from retinal, choroidal, and scleral tissues were determined by real-time reverse transcription polymerase chain reaction (RT-PCR). The expressions of the receptor M1 were also explored in the retina, choroid, and sclera using immunohistochemistry. RESULTS: There was a remarkable reduction in refractive error and increase in axial length after 8-weeks' green flickering light stimulation (P<0.001). The expression of M1 receptor mRNA in sclera and retina in myopia group were remarkably lower than that in group II and III (P<0.01). Significant reduced expression of M1 receptor stimulated by green flickering light in retina and sclera tissues were also observed (P<0.05). However, there was no M1 receptor expression in choroid in 3 groups. CONCLUSION: Myopia can be induced by 8 weeks' green flickering light exposure in the animal model. M1 receptor may be involved causally or protectively in myopia development.

Overexpression of human telomerase reverse transcriptase promotes the motility and invasiveness of HepG2 cells in vitro.

Recent studies have indicated that telomerase activity promotes cancer invasion and metastasis, but the underlying mechanism remains unclear. Several studies have shown that expression of exogenous human telomerase reverse transcriptase (hTERT) can promote motility and invasiveness among telomerase-negative tumor cells, and inhibition of endogenous telomerase activity can reduce invasiveness in tumor cells. However, whether overexpression of hTERT can further enhance the motility and invasiveness of telomerase­positive tumor cells has yet to be determined. In the present study, we showed that stable overexpression of hTERT can increase telomerase activity and telomere length, which significantly promotes the invasive and metastatic potential of telomerase­positive HepG2 cells but does not affect cell proliferation. Further analysis suggested that enhanced invasiveness and metastasis may act through corresponding upregulation of mRNA and protein expression of matrix metalloproteinase 9 (MMP9) and Ras homolog gene family member C (RhoC). Our study indicated that exogenous expression of hTERT may promote invasiveness and metastasis through upregulation of MMP9 and RhoC.

Simultaneous measurements of serum AFP, GPC-3 and HCCR for diagnosing hepatocellular carcinoma.

BACKGROUND/AIMS: Hepatocellular carcinoma (HCC) is a prevalent malignant tumor. Tumor markers are very useful in early diagnosis; however a single marker is rather limited. We launched a test to increase the diagnostic sensitivity through the combined detection. METHODOLOGY: Serum concentration of three tumor-markers, Glypican-3 (GPC-3), Human-Cervical-Cancer-Oncogene (HCCR) and a-fetoprotein (AFP), were determined in 189 samples: 101 cases of HCC, 40 cases of cirrhosis, 18 cases of hepatitis and 30 cases of control healthy donors. Every marker was evaluated for its diagnostic value by one-way-analysis-of-variance and receiver-operating-characteristics analysis. RESULTS: GPC-3 was the best marker with an area under the curve (AUC) of 0.892; using 26.8ng/mL as the cut-off for HCC diagnosis, GPC-3 has a sensitivity of 51.5% and maintains a specificity of 92.8%. HCCR, with an AUC of 0.831, can reach a sensitivity of 22.8% and maintain a specificity of 90.9% if the cut-off is set as 58.8mAU/mL. With an AUC of 0.827, the efficacy and sensitivity of AFP were 36.6% and 98.5% when using 199.3ng/mL as the cut-off. No significant correlation was found between these three markers. Simultaneously detecting three markers can significantly increases the sensitivity to 80.2%, much higher than AFP alone. CONCLUSIONS: GPC-3 and HCCR are useful tumor markers complementary to AFP for clinical diagnosis of HCC.

A novel system of artificial antigen-presenting cells efficiently stimulates Flu peptide-specific cytotoxic T cells in vitro.

Therapeutic numbers of antigen-specific cytotoxic T lymphocytes (CTLs) are key effectors in successful adoptive immunotherapy. However, efficient and reproducible methods to meet the qualification remain poor. To address this issue, we designed the artificial antigen-presenting cell (aAPC) system based on poly(lactic-co-glycolic acid) (PLGA). A modified emulsion method was used for the preparation of PLGA particles encapsulating interleukin-2 (IL-2). Biotinylated molecular ligands for recognition and co-stimulation of T cells were attached to the particle surface through the binding of avidin-biotin. These formed the aAPC system. The function of aAPCs in the proliferation of specific CTLs against human Flu antigen was detected by enzyme-linked immunospot assay (ELISPOT) and MTT staining methods. Finally, we successfully prepared this suitable aAPC system. The results show that IL-2 is released from aAPCs in a sustained manner over 30 days. This dramatically improves the stimulatory capacity of this system as compared to the effect of exogenous addition of cytokine. In addition, our aAPCs promote the proliferation of Flu antigen-specific CTLs more effectively than the autologous cellular APCs. Here, this aAPC platform is proved to be suitable for expansion of human antigen-specific T cells.

[Effect of protein kinase C/transforming growth factor beta 1 pathway on activation of hepatic stellate cells].

OBJECTIVE: To investigate the effect of protein kinase C (PKC)/transforming growth factor beta 1 (TGF beta1) pathway on activation of hepatic stellate cells (HSC). METHODS: HSC rHSC-99 cell line was used in three groups in this study. Group A served as a control. In group B the HSC were incubated with PKC agonist PMA (0.5 micromol/L), and in group C the cells were incubated with PKC inhibitor calphostin C (100 nmol/L). The PKC activities were detected at different incubation time points (0, 3, 6, 12 and 24 h). Western blot and RT-PCR were used to detect the expression of TGF beta1, Smad 4, collagen type I, III and alpha-smooth muscle actin (alpha-SMA) at the 24 h point. Cell proliferation was assessed by MTT colorimetric assay. RESULTS: PMA increased the activity of PKC significantly, whereas calphostin C inhibited the activity of PKC. The increased activity of PKC promoted the HSC to express TGF beta1, Smad 4, collagen type I, III and alpha-SMA. In comparison with the controls, the expressions of TGF beta1, Smad 4, collagen type I, III and alpha-SMA increased 4.8, 13.1, 2.4, 1.8 and 1.3 fold respectively (P < 0.01). PKC promoted the proliferation of HSC. The above effects were inhibited by the inhibition of PKC activity. CONCLUSION: Changing of PKC activity can regulate and control the expression of TGF beta1, which may play a role in regulating the activation of HSC.

Effects of 5-hydroxytamine and its antagonists on hepatic stellate cells.

BACKGROUND: Hepatic stellate cell (HSC) plays a key role in hepatic fibrosis. This study was undertaken to investigate the expression of 5-hydroxytamine receptors in HSC and the effect of 5-hydroxytamine on biological characteristics of HSC. METHODS: Liver ex vivo perfusion of collagenase and density gradient centrifugation were used to isolate HSCs. Reverse transcriptase polymerase chain reaction (RT-PCR) was used to detect the expression of 5-hydroxytamine receptor subtypes 1A, 2A, 2B and 3. Western blot hybridization was used to elucidate the effect of 5-hydroxytamine and its 2A receptor antagonist ketanserin and 3 receptor antagonist ondanosetron on the expression of transforming growth factor-beta1 (TGF-beta1) and Smad4 in HSC. RESULTS: HSC expressed 5-hydroxytamine receptor subtypes 1A, 2A and 2B. 5-hydroxytamine significantly increased the expression of TGF-beta1 and Smad4 in HSC (P<0.05). This action can be antagonized by ketanserin, not by ondanosetron. CONCLUSIONS: HSC expresses 5-hydroxytamine receptors. 5-Hydroxytamine could effect the biological characteristics of HSC through its receptor mediation, and may play a role in the pathogenesis of liver cirrhosis and portal hypertension.

[An in vivo study on interlukin-10 inhibiting the expression and secretion of collagen I and IV in hepatic stellate cells].

OBJECTIVES: To investigate the effect of interlukin-10 (IL-10) on expression and secretion of collagen I, IV in rat's hepatic stellate cells (HSC) of livers injured by CCl4. METHOD: The adenovirus vector encoded IL-10 gene was used to transfect rats with liver injury via the caudal veins. HSC were isolated and purified from the rat livers by collagenase IV perfusion and density gradient centrifugation with Nycodenz. The expression of collagen I, IV mRNA in HSC was detected by semi-quantitative RT-PCR method and the secretion of collagen I, IV in culture serum of HSC by ELISA method. The quantity of collagen was measured in the van Gieson stained histological liver preparations. RESULTS: The expression and secretion of collagen I, IV in the adenovirus vector encoding IL-10 gene group were significantly lower than those in the adenovirus vector without IL-10 gene group and the control group (P < 0.05). The quantity of collagen in the treatment group was lower than that in the control group. CONCLUSION: IL-10 can inhibit collagen I, IV expression and secretion in rat HSC.

[Downregulation of transforming growth factor-beta1 and platelet-derived growth factor gene expression by interleukin-10 in murine hepatic stellate cells in response to experimental liver injury].

OBJECTIVE: To investigate the effect of interleukin-10 (IL-10) on the expression of transforming growth factor-beta(1) (TGFbeta(1)) and platelet-derived growth factor (PDGF) in hepatic stellate cells (HSC) during liver injury. METHODS: The adenovirus vector (the titer was 1 x 10(7) efu/ml) encoded IL-10 gene was used to transfect the rat via the vein of caudal. At the same time, CCl(4) was injected into rat by a hypodermic injection. These processes went on twice a week. After eight weeks, the liver were perfused with collagenase IV and purified by density gradient centrifugation with Nycodenz for separate HSC. The level of IL-10 was measured by ELISA method; The expression of PDGF and TGFbeta(1) in HSC was detected by semi-quantitative RT-PCR and Western-blot methods. RESULTS: The level of IL-10 in therapy group (adenovirus vector encoding IL-10 gene group) was higher than that in non-therapy group (adenovirus vector without IL-10 gene and PBS group); The expression of TGFbeta(1) mRNA, TGFbeta(1) protein and PDGF mRNA, PDGF protein in therapy group were significantly lower than that in non-therapy group (P < 0.05). CONCLUSION: Downregulating the TGFbeta(1) and PDGF expression could be the passageway by which IL-10 alleviate the degree of proliferation and activation in hepatic stellate cells.

[Inducing hepatocellular carcinoma-specific cytotoxic T lymphocyte response using formed by fusion of FastDCs and allogeneic human hepatocellular carcinoma cells].

OBJECTIVE: To fuse human hepatocellular carcinoma (HCC) cells with mature monocyte-derived dendritic cells (FastDC) and to observe in vitro the function of the fused cells in stimulating autologous T cells proliferation and inducing HCC-specific cytotoxic T lymphocyte (CTL) response. METHODS: CD14(+) cells were isolated and purified from the peripheral blood of a healthy HLA-A2 blood donor and cultured in fresh dendritic cell complete medium for 24 h, then proinflammatory mediators were supplemented for another 24 h, thus generating mature dendritic cell (FastDCs). The FastDCs were fused with human HCC cells of the line HCCLM3 to generate novel dendritoma. T cells were isolated from selected CD14(-) cells and then divided into 4 groups to be stimulated with dendritoma cells, DCs, HCCLM3 cells, and mixed DCs-HCCLM3 cells respectively for 96 hours. 18 hours before the end of cultivation (3)H-TdR was added into the culture fluid. Scintillation counter was used to measure the cpm values. CD8(+)T cells were isolated from CD14(-) cells, and added with different stimulating cells radiated by (60)Co and IL-2, IL-6, and IL-7. The values of IFN-gamma in the supernatants of the culture fluid of CD8(+)T cells with dendritoma cells, DCs, HCCLM3 cells, and mixed DCs-HCCLM3 cells was measured. HCCLM3, K562, HLE, self monocytes labeled with Na(2)(51)CrO(4) were added with effector cells, gamma-scintillation counter was used to measure the cpm value so as to calculate the killing ability of CTL. RESULTS: The CTLs activated by dendritoma cells specifically killed the HCCLM3 cells in the context of MHC class I and acted less vigorously against the control target cells. The CTLs activated by dendritoma cells were stronger in killing HCCLM3 cells than DCs, HCCLM3 cells, and mixed DCs-HCCLM3 cells (all P < 0.05). The killing activity was decreased on the HCCLM3 cells incubated with anti-HLA-ABC antibody. Three, five, and seven days after co-cultivation the value of IFN-gamma in the supernatants of the culture fluid of CD8(+)T cells with fused cells, DCs, HCCLM3 cells, and mixed DCs-HCCLM3 cells increased gradually, especially in the supernatants of the culture fluid of CD8(+)T cells with dendritoma cells (400 pg/ml +/- 60 pg/ml 3 days after, 1030 pg/ml +/- 160 pg/ml 5 days after, and 1260 pg/L +/- 180 pg/L 7 days after). CONCLUSION: The novel dendritomas formed with HCCLM3 cells and mature FastDCs from healthy human peripheral blood CD14(+) monocytes are potent stimulators for CD8(+)T cells in inducing HCCLM3 cell-specific lysis. With shorter time required for in vitro DC development, the rapid method of generation of dendritoma is more economic and may represent a new strategy for immunotherapy of hepatocellular carcinoma.

A novel, rapid strategy to form dendritomas from human dendritic cells and hepatocellular carcinoma cell line HCCLM3 cells using mature dendritic cells derived from human peripheral blood CD14+ monocytes within 48 hours of in vitro culture.

AIM: Dendritomas formed by fusing cancer cells to dendritic cells have already been applied to clinical treatment trial of several types of cancers. Dendritic cells for the fusion in most trials and experiments were from blood monocytes in standard 7-d protocol culture, which requires 5-7 d of culture with granulocyte-macrophage-colony-stimulating factor (GM-CSF) and interleukin-4 (IL-4), followed by 2-3 d of activation with a combination of proinflammatory mediators such as tumor necrosis factoralpha (TNFalpha), interleukin-1beta (IL-1beta), interleukin-6 (IL-6) and prostaglandin E(2) (PGE(2)). One study showed that mature monocyte-derived dendritic cells could be obtained within 48 h of in vitro culture with the same protocol as standard 7-d culture and referred to as FastDCs. Here we aimed to fuse human hepatocellular carcinoma cell line HCCLM3 cells with mature monocyte-derived dendritic cells within 48 h of in vitro culture (FastDC). METHODS: HCCLM3 cells were cultured in RPMI 1640 with 150 mL/L fetal calf serum (FCS). CD14+monocytes from healthy human peripheral blood were purified with MACS CD14 isolation kit and cultured in six-well plates in fresh complete DC medium containing RPMI-1640, 20 mL/L heat inactivated human AB serum, 2 mmol/L L-glutamine, 100 microg/mL gentamicin, 1 000 U/mL GM-CSF and 500 U/mL IL-4 for 24 h, then proinflammatory mediators such as TNFalpha (1 000 U/mL), IL-1beta (10 ng/mL), IL-6 (10 ng/mL) and PGE(2) (1 microg/mL) were supplemented for another 24 h, and thus mature FastDCs were generated. HCCLM3 cells and FastDCs were labeled with red fluorescent dye PKH26-GL and green fluorescent dye PKH67-GL respectively. After the red fluorescent-stained HCCLM3 cells were irradiated with 50 Gy, FastDCs and irradiated HCCLM3 cells were fused in 500 mL/L polyethylene glycol(PEG)+100 mL/L dimethyl sulfoxide (DMSO) to generate novel dendritomas. The FastDCs and novel dendritomas were immunostained with anti-CD80, anti-CD86, anti-CD83, anti-HLA-DR mAbs and analyzed by fluorescence-activated cell sorting (FACS). Novel dendritomas were nucleus-stained with Hoechst 33258 and analyzed by confocal laser scanning microscopy. RESULTS: Mature FastDCs with highly expressed surface markers CD80, CD86, CD83 and HLA-DR were generated within 48 h in vitro. Novel dendritomas with dual red-green fluorescence were constructed fast and successfully, and FACS analysis showed that the fusion efficiency was 24.27% and the novel dendritomas expressed the same activation markers as FastDCs. Confocal laser scanning microscopy analysis showed representative images of dendritomas. CONCLUSION: Dendritomas can be formed fast with mature FastDCs from healthy human peripheral blood monocytes (PBMC) by incubation with GM-CSF and IL-4 for 24 h and by activation with proinflammatory mediators for an additional period of 24 h. Owing to shorter time required for in vitro DCs development, the generation of these novel dendritomas reduced labor and cost. This rapid method for formation of dendritomas may represent a new strategy for immunotherapy of hepatocellular carcinoma.

Inhibitory effect of retroviral vector containing anti-sense Smad4 gene on Ito cell line, LI90.

BACKGROUND: Transforming growth factor-beta1 (TGF-beta1) exerts strong fibrogenic potential in culture-activated HSCs. Smad4 is a key intracellular mediator for the transforming growth factor-beta (TGF-beta) superfamily of growth factors. The aim of this study was to assess the effects of the antisense Smad4 gene on Ito cell line, LI90. METHODS: The recombinant retroviral vector pLXSN-Smad4 was constructed by cloning the rat antisense Smad4 cDNA into the retroviral vector pLXSN. Retroviruses with or without the antisense gene were obtained by transfecting pLXSN-Smad4 and pLXSN vectors into PA317 cells. Human hepatic stellate cells (HSCs) LI90 were infected with these retroviruses followed by selection with G418. The expression of Smad4 was detected by Northern and Western blots. Cell biological characteristics, including cell growth curve, 3H-TdR and 3H-proline uptake by HSCs and the production of extracellular matrix were assessed. RESULTS: mRNA and protein expressions of Smad4 in LI90 cells transfected with retrovirus containing the antisense Smad4 gene were much lower than those in LI90 cells transfected with empty vector or parental LI90 cells. Cells hypoexpressing the Smad4 gene exhibited a slower rate of growth, a lower uptake of 3H-TdR and 3H-proline (P < 0.01), and smaller production of th extracellular matrix, compared with parental LI90 cells and cells transfected with empty retrovirus. CONCLUSIONS: The antisense Smad4 gene can suppress the expression of the Smad4 gene, reduce endogenous production of Smad4 mRNA and protein, block TGF-beta1 signaling pathway, inhibit activation of Ito cells, obstruct the growth of Ito cells, decrease the production of the extracellular matrix (ECM). Our results may provide a basis for the development of antifibrotic gene therapy.

[The effect of somatostatin analogue on expression of connective tissue growth factor gene of rat hepatic stellate cells].

OBJECTIVE: To investigate the effect of somatostatin analogue-octreotide (OCT) on expression of connective tissue growth factor (CTGF) gene of murine hepatic stellate cells (HSCs) in vitro. METHODS: HSCs separated from Sprague Dawley rats by in situ perfusion and Nycodenz gradient were divided into 5 groups. HSCs in 4 out of 5 groups were co-cultured with octreotide at different dosages, and the remaining group served as control. The expression of CTGF and TGF-beta mRNA were assessed by reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: OCT down-regulates the expression of CTGF and TGF-beta mRNA in HSCs. The effect is increased with a dose dependent manner. CONCLUSIONS: OCT could exert the inhibitory effect on HSCs by down-regulating the expression of CTGF and TGF-beta. This provides a potential for the prevention and management of hepatic fibrosis.

[Effects of anti-sense Smad4 gene on the biological characteristics of the fat-storing cell line CFSC].

OBJECTIVE: To investigate the effects of antisense Smad(4) on the biological characteristics of the fat-storing cell line CFSC. METHODS: Fat-storing cells of line CFSC from rat with liver fibrosis were cultured and transfected with 50 MOI of recombinant adenoviral vector carrying antisense Smad(4) (AdvATSmad(4)) or the control empty adenovirus (Adv0), both produced by 293 packaging cells, respectively. Two, four, and six days after the transfection the cultured cells were collected to undergo trypan blue staining and cell counting. The growth curves were drawn. The presence of antisense Smad(4) was detected by RT-PCR and Western blotting. (3)H-TdR was added into the culture media to be co-cultured for 6 hours. Then the cells were collected to examine the (3)H-TdR incorporation rate. RT-PCR and immunohistochemistry were used to examine the expression of COL1A1 and type I collagen, kinds of extracellular matrix (ECM). RESULTS: Compared with the control CFSC and the Adv0-transfected CFSC cells, the cell growth curve, (3)H-TdR incorporation rate, proline incorporation rate, expression of Smad(4), and expression of extracellular matrix were markedly decreased in the AdvATSmad(4)-transfected CFSCs. CONCLUSION: The antisense Smad(4) gene inhibits the expression of Smad(4) mRNA and protein, proline incorporation and cell growth, thus down-regulating the production of ECM. Antisense Smad(4) gene may be used as a choice of gene therapy for liver fibrosis.