MC Cell Research Articles

Jianwei Xiaoyan granule ameliorates chronic atrophic gastritis by regulating HIF-1α-VEGF pathway

Ethnopharmacological relevanceJianwei Xiaoyan Granule (JWXYG) is the traditional Chinese medicine preparation in Jiangyin Hospital Affiliated to Nanjing University of Chinese Medicine, which has been widely used in clinical treatment of chronic atrophic gastritis (CAG). However, the material basis and potential mechanism of JWXYG in the treatment of CAG are not clear. PurposeTo explore the material basis and potential mechanism of JWXYG in the treatment of CAG. MethodsIn this study, the components of JWXYG were analyzed by HPLC-Q-TOF-MS/MS. Then, the CAG model in rats established by a composite modeling method and MC cell model induced by MNNG were used to explore the improvement effect of JWXYG on CAG. Finally, the potential mechanism of JWXYG in the treatment of CAG was preliminarily predicted based on network pharmacology and validated experimentally. ResultsThirty-one components of JWXYG were analyzed through HPLC-Q-TOF-MS/MS, such as albiflorin, paeoniflorin, lobetyolin firstly. Research results in vivo showed that the gastric mucosa became thinner, intestinal metaplasia appeared, the number of glands was reduced, the serum levels of PG I and PG II increased and the contents of G17 and IL-6 reduced in CAG model rats. After 4 weeks of JWXYG (2.70 g/kg) administration, these conditions were significantly improved. In addition, cell viability, migration, and invasion of MNNG-induced MC cells was inhibited by JWXYG treatment (800 μg/mL). Furthermore, the results of network pharmacology indicated that HIF-1 and VEGF signaling pathways might play important roles in the therapeutic process. Then the results of Western blot, immunohistochemistry and immunofluorescence confirmed that with JWXYG treatment, the increased expression of HIF-1α, VEGF and VEGFR2 in gastric issue of CAG rats were restrained. Eventually, potential components of JWXYG in the treatment of CAG were predicted through molecular docking to elucidate the material basis. ConclusionJWXYG could inhibit angiogenesis by regulating HIF-1α-VEGF pathway to exert therapeutic effects on CAG. Our study explored the potential mechanisms and material basis of JWXYG in the treatment of CAG and provides experimental data for the clinical rational application of JWXYG.

Celastrus orbiculatus extract reverses precancerous lesions of gastric cancer by inhibiting autophagy via regulating the PDCD4-ATG5 signaling pathway.

Celastrus orbiculatus ethyl acetate extract (COE) is the main extract of the stem of the Chinese herbal C. orbiculatus, which has anti-tumor and anti-inflammatory biological effects. Our previous study showed that COE had a certain reversal effect on the precancerous lesions of gastric cancer (PLGC) in rats, but the exact mechanism of action remains elusive. We aimed to explore the therapeutic effects of COE on PLGC and the potential mechanisms. The PLGC rat model was successfully constructed by N-methyl-N´-nitro-N-nitrosoguanidine (MNNG) multifactorial induction method. Then, COE was prepared to treat the PLGC rat model. Hematoxylin & eosin staining was used to observe gastric mucosal lesions in rats, AB-PAS and HID-AB staining were used to observe intestinal metaplasia. PDCD4-ATG5 signaling pathway was detected by immunohistochemistry (IHC) and reverse transcription polymerase chain reaction (RT-PCR) in vivo, and autophagy level was detected by IHC, transmission electron microscopy, and RT-PCR in vivo. Besides, the PLGC (MC) cell model was successfully constructed by treating GES-1 cells with MNNG. Then, the morphology, proliferation, and apoptosis of MC cells, and the role of the PDCD4-ATG5 signaling pathway and autophagy in MC cells were evaluated by COE and after the overexpression of PDCD4 treatment. COE significantly improved gastric mucosal injury and cellular heteromorphism and retarded the progression of PLGC in rats. Further studies indicated COE not only inhibited the level of autophagy but also interfered with the PDCD4-ATG5 signaling pathway in vivo. On the other hand, COE treatment could effectively reverse MC cell damage, inhibit MC cell proliferation, and promote MC cell apoptosis. Furthermore, COE also promoted PDCD4 and inhibited ATG5 expression in vitro, and the inhibitory effect of COE on ATG5-mediated autophagy was further enhanced after the overexpression of PDCD4. The study revealed that COE could regulate the PDCD4-ATG5 signaling pathway to inhibit autophagy in gastric epithelial cells, which contributes to reversing the progression of PLGC.

Multivitamin complex-loaded electrospun polyvinyl alcohol core/shell structure fibers for transdermal delivery system: In-silico and experimental studies

Transdermal delivery systems offer a controlled and targeted environment for releasing drugs compared to other delivery systems. This study presents the fabrication of polyvinyl alcohol (PVA) fibers with a multivitamin complex (MV) using the electrospinning technique (ES). The research focuses on understanding how various fiber structures, such as core/shell, simple fibers, and ES parameters, affect the MC release mechanism and cell viability behavior.The vitamin complexes were uniformly encapsulated within the polymeric chains in all structure fibers. PVA simple fibers with and without the vitamin complex don't significantly differ in diameter size. However, the core/Shell fiber has a notable decrease in fiber diameter of 45 %.The fiber with a core/shell structure resulted in a slower release rate of the vitamin complex than simple fiber. According to the Korsmeyer-Peppas model, the release mechanism observed in our study for the simple fibers is classical Fickian diffusion. Instead, core/shell fibers indicate a more anomalous or non-Fickian behavior.The structural configurations of the fibers do not result in statistically significant differences in cell viability. This could be attributed to the identical nature of materials used, including the polymer and MV, across all cases.Finally, a computational chemistry study was used to examine the interaction between polyvinyl alcohol (PVA) and vitamins K3 and B3, like a model of MV. The analysis showed four strong hydrogen bonds between PVA and vitamin B3, whereas the interaction between PVA and vitamin K3 only had one hydrogen bond. Furthermore, the PVA and vitamin B3 interaction had higher energy and was more exothermic and spontaneous than the PVA-vitamin K3 interaction. On the other hand, the PVA-vitamin K4 interaction displayed higher reactivity due to its lower separation energy. In contrast, the PVA-vitamin B3 interaction was more stable.

Tanshinone I attenuates gastric precancerous lesions by inhibiting epithelial mesenchymal transition through the p38/STAT3 pathway

BackgroundGastric precancerous lesions (GPLs) are omens for gastric cancer (GC), which developing with a series of pathological changes of gastric mucosa. Reversing epithelial-mesenchymal transition (EMT) in gastric mucosa is the main approach to restrain GPLs from evolving into cancer. Tanshinone I (Tan-I), the active ingredients of traditional Chinese herb Salvia miltiorrhiza, has exhibited anticancer effect. PurposeTo investigate the effect and mechanism of Tan-I in intervening GPLs, and provide a new therapeutic strategy for prevention of GC. MethodsGastric mucosal epithelial cells were treated with the N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) to construct MNNG-induced cell (MC cell) of gastric mucosa that undergoing EMT process. Then, this study explored the effect and mechanism of Tan-I in vitro. Subsequently, this study constructed GPL mice to clarify the exact efficacy and mechanism of Tan-I on GPLs. ResultsTan-I inhibited MC cell proliferation, invasion and migration. Simultaneously, the aberrant expression of E-cadherin and N-cadherin were reversed. Tan-I attenuated inflammation by reducing the release of nitric oxide, TNFα and IL-1β. Tan-I reversed the EMT and inflammatory processes by regulating p38 and STAT3. ConclusionThis study showed that Tan-I inhibited the progression of GPLs by reversing the EMT process and reducing inflammation by restraining the p38/STAT3 signaling pathway.

Gallic acid alleviates gastric precancerous lesions through inhibition of epithelial mesenchymal transition via Wnt/β-catenin signaling pathway

Ethnopharmacological relevanceGallic acid (GA) is a natural polyphenolic compound derived from Rhus chinensis Mill. with a variety of biological activities such as astringent sweat, cough, dysentery, hemostasis, and detoxification, and is widely used in China as a treatment for cough, bleeding, and gastrointestinal disorders. In recent years, the anticancer activity of GA has been demonstrated in a variety of cancers, affecting multiple cellular pathways associated with cancer onset, development and progression. Aim of the studyTo investigate the role and potential mechanism of GA on gastric precancerous lesions (GPL), the key turning point of gastritis to gastric cancer, with the aim of delaying, blocking or reversing the dynamic overall process of “inflammation-cancer transformation” and thus blocking GPL to prevent the development of gastric cancer. Materials and methodsIn this study, we established N-Nitroso-N-methylurea (MNU)-induced GPL mice model and induced precancerous lesions of gastric cancer cells (MC), i.e. epithelial mesenchymal transition (EMT), in human gastric mucosal epithelial cells (GES-1) with N-methyl-N′-nitro-N-nitrosoguanidine (MNNG). We used conventional pathology, immunohistochemistry, RNA sequencing, Western blot and other techniques to study the therapeutic effect of GA on GPL and its possiblemechanism in vitro and in vivo. ResultsThe results showed that compared with normal GES-1 cells, MC cells had the characteristics of malignant cells such as abnormal proliferation, invasion and metastasis, accompanied by decreased expression of EMT-related protein E-cadherin and increased expression of N-cadherin and Vimentin. GA can inhibit the malignant behavior of MC cell proliferation and induce its G0/G1 phase arrest, which is achieved by downregulating the Wnt/β-catenin signaling pathway and thereby inhibiting the EMT process. However, when we incubated with the Wnt pathway activator (Wnt agonist 1), the effect of GA was reversed. Furthermore, analysis of human gastric specimens showed that activation of the Wnt/β-catenin pathway was significantly associated with GPL pathological changes. Meanwhile, GA reversed MNU-induced intestinal metaplasia and partial dysplasia in GPL mice. ConclusionTaken together, these results indicate that GA prevents the occurrence and development of GPL by inhibiting the Wnt/β-catenin signaling pathway and then inhibiting the EMT process, which may become potential candidates for the treatment of GPL.

Evaluation of Patient and Tumor Features to Optimize Urothelial Metastasis Treatment

<h3>Purpose/Objective(s)</h3> The treatment of oligometastatic disease is an evolving area of research in oncology. This study characterizes urothelial metastases to identify tumor and clinical features which may be used in patient selection. <h3>Materials/Methods</h3> We evaluated a prospectively collected institutional biorepository for patients with urothelial carcinoma metastases. Metastatic tissue was collected and profiled with Affymetrix GeneChips and the ESTIMATE and CIBERSOFT algorithms were used to infer the immune composition of metastases. Gene set enrichment analysis with select hallmark MSigDB pathways related to DNA damage repair were evaluated. Medical charts were queried for patient demographics as well as tumor and treatment characteristics. Univariable analysis (UVA) with Kaplan-Meier methods was used for time-to-event analysis for overall survival from metastatic collection (OSMC) and time to recurrence at site of MC (TTRMC) and compared by log-rank testing. Cox regression was used to assess ability of variable to predict outcome in a multivariable (MVA) model. <h3>Results</h3> A total of 24 patients were identified between 2006 and 2009 with urothelial metastases profiled for gene expression with adequate records for chart query. The majority were male (75%) and the media age at MC was 69 years (range 52-89). Twelve patients had synchronous metastases with 29% having >1 metastatic range (range 1-3). The median BMI was 25.3 and 8 patients had diabetes or hypercholesteremia. Five patients were on an ACE-inhibitor. Twenty-one patients received definitive local surgery and 15 had ≥ pT3 or N+ disease. Eleven received chemotherapy and 3 received RT prior to MC. After MC, 58% received chemotherapy and 46% received radiation at the MC site. A total of 17 patients recurred after MC with 10 being at the original MC site. Increased immune cell presence at the MC site had increased TTRMC (9.9 months vs 8.1 months, p=0.04). No specific immune cell type was associated with TTRMC. Receipt of definitive local therapy to the primary tumor (p= 0.015), chemotherapy after MC (p= 0.001) and immune cell presence (HR: 0.9; 95% CI: 0.99-1.0, p=0.019) were associated with OSMC. Enrichment of dendritic cells at the MC site was associated with inferior OSMC (8.32 vs 34.3 months, p <0.001). Only immune cell presence remained predictive (p= 0.04) for OSMC on MVA. Neither DNA damage repair pathways nor presence of patient metabolic dysregulation were associated with outcomes. <h3>Conclusion</h3> Not all oligometastatic sites are equivalent and may require tailored approaches. Here we find that immune cell enrichment may provide better local metastatic control and survival.

Erianin, the main active ingredient of Dendrobium chrysotoxum Lindl, inhibits precancerous lesions of gastric cancer (PLGC) through suppression of the HRAS-PI3K-AKT signaling pathway as revealed by network pharmacology and in vitro experimental verification

Ethnopharmacological relevanceDendrobium chrysotoxum Lindl, a well-known traditional Chinese medicinal herb used in the treatment of gastric disease, is distinguished as the first of the “nine immortal grasses”. Dendrobium chrysotoxum Lindl and the traditional Chinese medicine prescriptions containing Dendrobium chrysotoxum Lindl are often prescribed clinically to treat chronic gastritis and precancerous lesions of gastric cancer (PLGC), showing favorable clinical effects and medicinal value in the prevention of gastric cancer. However, the effective ingredients and pharmacological mechanisms through which Dendrobium chrysotoxum Lindl prevents and treats PLGC have not been adequately identified or interpreted. Aim of the studyThe present study aimed to evaluate the effective ingredients and pharmacological mechanisms of Dendrobium chrysotoxum Lindl in the prevention and treatment of PLGC using network pharmacology. In addition, in vitro verification was performed to evaluate the mechanism of action of Erianin, the main active ingredient in Dendrobium chrysotoxum Lindl, providing experimental evidence for the clinical use of Dendrobium chrysotoxum Lindl in the treatment of PLGC. Materials and methodsUsing network pharmacology methods, the main ingredients in Dendrobium chrysotoxum Lindl were screened from the ETCM, BATMAN-TCM, and TCMID databases, and their potential targets were predicted using the Swiss Target Prediction platform. The targets related to PLGC were retrieved through the GeneCard database, and the targets common to the main ingredients of Dendrobium chrysotoxum Lindl and PLGC were analyzed. The protein-protein interaction (PPI) network was obtained via the STRING database and analyzed visually using Cytoscape 3.7.2. The underlying mechanisms of the common targets identified through gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis were analyzed using DAVID online. The “component-target-pathway” networks of Dendrobium chrysotoxum Lindl and Erianin were visually constructed by Cytoscape 3.7.2. The biological activity evaluation of Erianin's effect on PLGC was carried out using MC cell lines, the PLGC cell model established using MNNG to induce damage in normal gastric mucosal epithelial cell (GES-1). After the intervention of different concentrations of Erianin, MC cell viability was explored using the MTT assays, cell migration was determined by wound healing assays, the cell cycle and apoptosis were analyzed using flow cytometry, and the expression levels of related proteins and their phosphorylation in the HRAS-PI3K-AKT signaling pathway were detected by Western blot. ResultsThe “component-target-pathway” network constructed in this study showed 37 active ingredients from Dendrobium chrysotoxum Lindl and 142 overlapping targets related to both Dendrobium chrysotoxum Lindl and PLGC. The targets were associated with a variety of cancer-related signaling pathways, including Pathways in cancer, PI3K-Akt signaling pathway, Rap1 signaling pathway, Focal adhesion, Ras signaling pathway, and MAPK signaling pathway. Notably, the network showed that Erianin, the primary active ingredient from Dendrobium chrysotoxum Lindl and the component associated with the most targets, could regulate Pathways in cancer, PI3K-AKT signaling pathway, Focal adhesion, Rap1 signaling pathway, cell cycle, and RAS signaling pathway in the treatment of PLGC. Verification through in vitro experiments found that Erianin can significantly inhibit MC cell viability, inhibit cell migration, block the cell cycle in the G2/M phase, and induce cell apoptosis in a dose-dependent manner. The results of the Western blot experiment further showed that Erianin can significantly decrease the protein expression levels of HRAS, AKT, p-AKT, MDM2, Cyclin D1, and p-Gsk3β, and increase the protein expression level of p21, which suggests that Erianin can treat PLGC by regulating the HRAS-PI3K-AKT signaling pathway. ConclusionThis study explained the positive characteristics of multi-component, multi-target, and multi-approach intervention with Dendrobium chrysotoxum Lindl in the treatment of PLGC. Our results suggest that Erianin may be a promising candidate in the development of prevention and treatment methods for PLGC. This study provided experimental evidence for the clinical use of Dendrobium chrysotoxum Lindl to treat PLGC and prevent gastric cancer.

Melochia corchorifolia extract inhibits melanogenesis in B16F10 mouse melanoma cells via activation of the ERK signaling.

Numerous researches have focused on discovering available inhibitors of melanogenesis from natural medicinal plants with stable efficacy and safety to resolve cutaneous hyperpigmentary problems. Melochia corchorifolia Linn. (MC) has been used as folk medicine to treat various diseases. However, the effect of MC on melanogenesis remains unknown. In this study, we investigated the effect of MC extract on melanogenesis and its underlying mechanisms in B16F10 mouse melanoma cells. B16F10 cells were treated with MC extract, and then, cell viability, melanin content, and tyrosinase activity were analyzed. The mRNA and protein expression of tyrosinase and microphthalmia-associated transcription factor (MITF) were evaluated using real-time quantitative polymerase chain reaction (RT-qPCR) and Western blotting, respectively. Phosphorylated or total protein levels in MC extract-induced signaling pathways were analyzed by Western blotting. Treatment of B16F10 cells with MC extract inhibited melanin synthesis and intracellular tyrosinase activity in a dose-dependent manner with no cytotoxicity. Protein and mRNA expressions of tyrosinase and MITF were also significantly decreased by MC extract treatment. In addition, phosphorylated level of extracellular signal-regulated kinase (ERK) was obviously increased by MC extract, but AKT pathway was not activated. Inhibited ERK phosphorylation by pretreatment with a selective ERK inhibitor PD98059 significantly reversed the decreased melanin content induced by treatment with MC extract in B16F10 cells. MC extract inhibits melanogenesis in B16F10 mouse melanoma cells through suppression of MITF-tyrosinase signaling pathway by ERK activation.

Mast Cell and Basophil Cell Lines: A Compendium.

Mast cells and basophils play a crucial role during type I hypersensitivity reactions. However, despite efforts to elucidate their role in the pathogenesis of allergy and inflammation, our understanding of MC and basophil biology is still relatively scarce. The practical difficulty in obtaining a sufficient number of purified primary cells from biological samples has slowed down the process of reaching a full understanding of the physiological role of these functionally similar cell types. The establishment of several immortalized cell lines has been a useful tool to establish and perform sophisticated laboratory protocols that are impractical using primary cells. Continuous cell lines have been extensively used to investigate allergen/IgE-mediated cell activation, to elucidate the degranulation dynamics, to investigate structural and functional properties of the high-affinity receptor (FcεRI), and to test cell-stabilizing compounds. In this chapter, we review the most widely used and better-characterized MC and basophil cell lines, highlighting their advantages and drawbacks. It must be pointed out, however, that while cell lines represent a useful in vitro tool due to their easy manipulability and reduced culture costs, they often show aberrant characteristics which are not fully representative of primary cell physiology; results obtained with such cells therefore must be interpreted with due care.

The correlation between DNA methylation and transcriptional expression of human dopamine transporter in cell lines

This study aims to investigate the relationship between DNA methylation and expression of human dopamine transporter (hDAT). We examined methylation status of hDAT in cells with various hDAT expression levels, including two dopaminergic neural cell lines (SK-N-AS and SH-SY-5Y) and one non-dopaminergic cell line (HEK293) by bisulfite sequencing PCR(BSP). The effects of DNA methyltransferase inhibitor 5-aza-dC or/and histone deacetylase inhibitor (HDACi, sodium butyrate, NaB) on the DNA methylation status and mRNA expression levels of hDAT were examined. The results revealed marked hypomethylation of the two promoter regions (-1214 to -856bp and -48 to 439bp, the first base of exon 1 was taken as +1 bp)of hDAT in SK-N-AS (4.7%±2.0mC and 3.5%±1.0mC, respectively) compared with SH-SY-5Y (88.0%±4.4%mC and 81.1%±8.8%mC) and HEK293 (90.7%±2.4mC and 84.4%±8.6% mC) cell lines, indicating a cell-specific methylation regulation of hDAT. 5-aza-dC and NaB decreased hypermethylation,while increase hDAT expression in SH-SY-5Y cells and recovered hDAT mRNA expression in HEK293 cells. DNA methylation enabled the cell-specific differential expression of the hDAT gene. hDAT silencing was reversed by the introduction of DNA hypomethylation via 5-aza-dC or/and NaB.

A Polysaccharide Isolated from Mycelia of the Lion's Mane Medicinal Mushroom Hericium erinaceus (Agaricomycetes) Induced Apoptosis in Precancerous Human Gastric Cells.

Hericium erinaceus is typically used in traditional Chinese medicine for mucosal protection, healing of gastric ulcers, and treatment of gastritis. We purified from the cultured mycelia of H. erinaceus a polysaccharide with anti-gastric ulcer and antigastritis activity, but its effects on gastric malignancy have not been elucidated. We examined the differential effects of this purified polysaccharide, named EP-1, on the human gastric (GES-1) cell line and a precancerous cell line (MC) that was transformed from GES-1 using N-methyl-N'-nitro-N-nitrosoguanidine. We observed that the polysaccharide potently induced cell apoptosis and cell cycle arrest at the G0/G1 phase in the MC cell line but did not have any effect on the GES-1 cell line at the same doses. Further mechanistic studies revealed that the polysaccharide exerted its activity through an apoptosis-associated pathway by modulating the expression of Bax, Bcl-2, and caspase-3. Differential effects of the polysaccharide on the GES-1 and MC cell lines indicate that the polysaccharide was effective in preventing gastric cancer progression.

Anti-Gastric Ulcer Activity of Polysaccharide Fraction Isolated from Mycelium Culture of Lion's Mane Medicinal Mushroom, Hericium erinaceus (Higher Basidiomycetes).

Hericium erinaceus is a culinary-medicinal mushroom that is used in traditional medicine, in folk medicine, and as medicinal cuisine in Asian countries such as China, Japan, and Korea. H. erinaceus exhibits various pharmacological properties, such as anti-cancer, immunomodulation, anti-dementia, and anti-gastric ulcer effects. The extracts of the fruiting body of H. erinaceus demonstrate anti-gastritis activity. However, the active principle in the extract, as well as the mechanism to treat gastric ulcers, remains uncertain. The current study aims to identify the active component, with anti-gastric ulcer function, from the extracts of the H. erinaceus mycelium culture. In the experiment, anti-gastric ulcer activity was evaluated using an ethanol-induced ulcer model in mice and with an 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide assay using MC cell lines. The results suggest that the polysaccharide fraction can significantly decrease the ulcerated area compared with the control group and the effect is fairly dose dependent, irrespective of animal or cell experiments. These results indicate that the polysaccharide fraction is the active component of the H. erinaceus mycelium culture, which protects against gastric ulcers.

Author Response: Frequency-Doubling Technology and Parasol Cells

Author Response: Frequency-Doubling Technology and Parasol Cells

Lysyl Oxidase Binds Transforming Growth Factor-; and Regulates Its Signaling via Amine Oxidase Activity

Lysyl oxidase (LOX), an amine oxidase critical for the initiation of collagen and elastin cross-linking, has recently been shown to regulate cellular activities possibly by modulating the functions of growth factors. In this study, we investigated the interaction between LOX and transforming growth factor-beta1 (TGF-beta1), a potent growth factor abundant in bone, the effect of LOX on TGF-beta1 signaling, and its potential mechanism. The specific binding between mature LOX and mature TGF-beta1 was demonstrated by immunoprecipitation and glutathione S-transferase pulldown assay in vitro. Both proteins were colocalized in the extracellular matrix in an osteoblastic cell culture system, and the binding complex was identified in the mineral-associated fraction of bone matrix. Furthermore, LOX suppressed TGF-beta1-induced Smad3 phosphorylation likely through its amine oxidase activity. The data indicate that LOX binds to mature TGF-beta1 and enzymatically regulates its signaling in bone and thus may play an important role in bone maintenance and remodeling.

Effects of Radix notoginseng extracts drug-containing serum on expressions of bcl-2, Bax and p21WAF1 proteins in MNNG transformed GES-1 cells

To investigate the effects of Radix notoginseng extracts drug-containing serum on the expressions of apoptosis-regulating proteins including Bax, bcl-2 and p21WAF1 in precancerous gastric cells. The N-methyl-N'-nitro-N-nitroso-guanidine (MNNG) transformed eternalized human gastric mucosa epithelium GES-1 cell line (MC cell) was used in vitro as a model of gastric precancerous lesion. The medicated canine serum was prepared by feeding to the adult Beagle dog with Radix notoginseng extracts and obtaining the serum after 2-hour medication. MC cells were cultured with medicated canine serum (medicated serum group) or non-medicated canine serum (normal control group) for 72 hours. Expressions of Bax, bcl-2 and p21WAF1 proteins were detected by immunocytochemical assay and the average optical density of the cells was determined by an image analysis system. Compared with those of the normal control group, Bax and p21WAF1 expressions in medicated serum group were significantly enhanced (P<0.01), while the expression of bcl-2 was significantly reduced (P<0.01). Radix notoginseng extracts may inhibit the proliferation and promote the apoptosis of precancerous gastric cells through altering expressions of the bcl-2, Bax and p21WAF1 genes.

Iodine Deficiency Induces a Thyroid Stimulating Hormone-Independent Early Phase of Microvascular Reshaping in the Thyroid

Expansion of the thyroid microvasculature is the earliest event during goiter formation, always occurring before thyrocyte proliferation; however, the precise mechanisms governing this physiological angiogenesis are not well understood. Using reverse transcriptase-polymerase chain reaction and immunohistochemistry to measure gene expression and laser Doppler to measure blood flow in an animal model of goitrogenesis, we show that thyroid angiogenesis occurred into two successive phases. The first phase lasted a week and involved vascular activation; this process was thyroid-stimulating hormone (TSH)-independent and was directly triggered by expression of vascular endothelial growth factor (VEGF) by thyrocytes as soon as the intracellular iodine content decreased. This early reaction was followed by an increase in thyroid blood flow and endothelial cell proliferation, both of which were mediated by VEGF and inhibited by VEGF-blocking antibodies. The second, angiogenic, phase was TSH-dependent and was activated as TSH levels increased. This phase involved substantial up-regulation of the major proangiogenic factors VEGF-A, fibroblast growth factor-2, angiopoietin 1, and NG2 as well as their receptors Flk-1/VEGFR2, Flt-1/VEGFR1, and Tie-2. In conclusion, goiter-associated angiogenesis promotes thyroid adaptation to iodine deficiency. Specifically, as soon as the iodine supply is limited, thyrocytes produce proangiogenic signals that elicit early TSH-independent microvascular activation; if iodine deficiency persists, TSH plasma levels increase, triggering the second angiogenic phase that supports thyrocyte proliferation.

Apoptosis-promoting effect of Panax notoginseng extracts on MNNG-transformed GES-1 cells

To study the apoptosis-promoting effect of the serum from Panax notoginseng extracts-fed dog on precancerous gastric cells by means of flow cytometry. In the experiment, we adopted eternalized human gastric mucosa epithelium GES-1 cells transformed by N-methyl-N'-nitro-N-nitroso-guanidine (MNNG) (MC cells) as the model of precancerous lesions for study in vitro. We took the serum of a dog before and at two different points of time (2 and 6 hours) after feeding the dog with Panax notoginseng extracts for experiment. The MC cells were cultured in mediums with different concentrations of the medicated serum at 2- or 6-hour point of time for 72 hours. By means of flow cytometry, we examined the apoptosis-promoting effects of the serums on the MC cells. The medicated serums at these 2 points of time had significant effects in promoting MC cell apoptosis. The proportions of apoptotic cells in culture mediums with medicated serums had a significant increase as compared with those in culture mediums with non-medicated serums (serum obtained before administration of extracts to the dog) under the same conditions (P<0.05). The number of MC cells in G(0)/G(1)phase was decreased (P<0.05) and that in G(2)/M phase increased (P<0.05), while no consistent changes were observed in S phase. The medicated serums obtained at the two different points of time have significant apoptosis-promoting effects on MC cells. They decrease the number of MC cells in G(0)/G(1) phase and increase the number of MC cells in G(2)/M phase. This is probably responsible for the effects of Panax notoginseng extracts in inhibiting the proliferation of MC cells and promoting its apoptosis.

Enhanced photocurrent by Schottky-barrier solar cell composed of regioregular polythiophene with merocyanine dye

When electron-transfer from poly(3-hexylthiophene-2, 5-diyl) (PTh6) to merocyanine dye (MC) occurred in the mixed solid under illumination, the photocurrent of Al/MC+PTh6 mixed solid Schottky-barrier cell was enhanced compared to that of pure MC or pure PTh6 cell. This is because discrete pairs of electron and hole created by the photoinduced electron-transfer are effectively separated in the electric field formed at the Al/organic solid interface.

Human prodynorphin gene generates several tissue-specific transcripts

The present study analyzes the transcription of the human prodynorphin gene. Transfection experiments indicate that promoter activity for the 2.8 kb `brain-type' human prodynorphin mRNA resides in the DNA region located 140–180 b upstream of the exon 1/intron A boundary and not 1.2 kb further upstream, as proposed by others [S. Horikawa, T. Takai, M. Toyosato, H. Takahashi, M. Noda, H. Kakidani, T. Kubo, T. Hirose, S. Tanayama, H. Hayashida, T. Miyata, S. Numa, Isolation and structural organization of the human preproenkephalin B gene, Nature 306, 1983, pp. 611–614]. The new data locates the human prodynorphin gene promoter for the brain-type mRNA in a position corresponding to the position of the rat prodynorphin gene promoter [J. Douglass, C.T. McMurray, J.E. Garett, J.P. Adelman, L. Calavetta, Characterization of the rat prodynorphin gene, Mol. Endocrinol. 3, 1989, pp. 2070–2078]. Three previously not described types of human prodynorphin mRNA of the same size, 2.8 kb, one expressed in fetal brain and two others in testis, were characterized in this study. These mRNAs are generated by alternative splicing of novel 5′-uppermost exons and transcription is probably initiated from other promoters. Human neuroblastoma SH–SY5Y and SK–N–MC cell lines previously used in studies of gene transcription have the 2.8 kb prodynorphin mRNA of adult brain alongside a more abundant, shorter 2.3 kb transcript. The latter transcript was also found in testis and in fetal brain. It lacked the 5′-part of the 2.8 kb mRNA including the signal peptide encoding sequence. The complex pattern of prodynorphin gene expression and its functional consequences are issues for further studies.

A Monte Carlo study of crystal structure transformations

The Metropolis algorithm has been generalized to allow for the variation of shape and size of the MC cell. A calculation using different potentials illustrates how the generalized method can be used for the study of crystal structure transformations. A restricted MC integration in the nine dimensional space of the cell components also leads to the stable structure for the Lennard-Jones potential.