RESUMEN
To explore the effects of forest types and slope positions on the content of soil organic carbon (SOC) and total nitrogen (TN) in the lower hilly area of Taihang Mountains, we examined the distribution pattern of SOC and TN contents in Quercus variabilis plantation (Qo), and Platycladus orientalis plantation (Po), and abandoned land (Al). The results showed that in the same forest type or slope position, the contents of SOC and TN gradually decreased with increasing soil depth. Under different slope conditions, the contents of SOC and TN showed the tendency of upper-slope (U) > middle-slope (M) > lower-slope (L) in the planted forests (Qo and Po), but showed the tendency of L>U>M in Al. Under different forest types, the contents of SOC and TN in the U and M showed the trend of Qo>Po>Al. At the LS, the contents of SOC and TN of Al were the highest. The C/N ratio followed an order of Qo>Po> Al at U and M, while Qo>Al> Po at L. Within the same forest type, C/N of different slopes was different, but not significant. Our results suggested that the adaptability of the Qo plantation is the best in the lower hilly area of Taihang Mountains.
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Bosques , Carbono , Mentón , Nitrógeno , SueloRESUMEN
A pot experiment was conducted to study the effects of irrigation with regenerated water on the growth, nutrient uptake, and quality of alfalfa. Four treatments were installed, i.e., irrigation with fresh water (Q), irrigation with regenerated water (Z), mixed irrigation with regenerated water and fresh water (Z + Q), and rotational irrigation with regenerated water and fresh water (Z/Q). Comparing with treatment Q, treatment Z increased the stem length, lateral branch number, and plant biomass significantly, but decreased leaf area. Treatments Z, Z + Q, and Z/Q increased plant soluble protein content by 78.43%, 83.68% and 72.53%, respectively, but treatment Z decreased plant soluble sugar content. Treatment Z increased plant Ca and Mg contents by 27.78% and 26.61%, and treatments Z and Z + Q decreased plant Fe content by 28.71% and 10.09%, respectively. Treatments Z, Z + Q, and Z/Q increased the cadmium content in above-ground part of alfalfa by 98.6%, 89.5%, and 59.0%, respectively, but the cadmium and lead contents were still lower than the thresholds of National Sanitation Standard (GB 13078-2001). It was suggested that regenerated water could be used as a source of irrigation water in alfalfa growth, but its long-term effect should be concerned.
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Agricultura/métodos , Medicago sativa/crecimiento & desarrollo , Agua/metabolismo , Biomasa , Medicago sativa/metabolismo , Control de Calidad , Agua/farmacologíaRESUMEN
Hypoxia, a decrease in oxygen tension occurring in pathological tissues, has a profound effect on macrophage functions. In this study, we have investigated cellular and molecular responses of murine macrophage-like RAW264.7 cells to low oxygen tension. Our study revealed that hypoxia induced RAW264.7 cells apoptosis and cell cycle arrest at G0/G1 phase. The result of Western blotting showed that the expression of apoptosis related signaling molecules, such as AKT and JNK was activated under hypoxia. The result of electrophoretic mobility shift assay showed that the DNA binding activity of nuclear factor kappa B (NF-kappaB) was also increased by hypoxic stimulation. Furthermore, gene expression profiles of RAW264.7 macrophages induced by hypoxia showed that hypoxia treatment may alter expression of genes related to apoptosis, survival, cell cycle, metabolism and structural matrix.
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Apoptosis , Hipoxia de la Célula , Expresión Génica , Macrófagos/metabolismo , Transducción de Señal , Animales , Apoptosis/genética , Ciclo Celular/genética , Hipoxia de la Célula/genética , Línea Celular , ADN/metabolismo , Perfilación de la Expresión Génica/métodos , MAP Quinasa Quinasa 4/metabolismo , Macrófagos/patología , Ratones , FN-kappa B/metabolismo , Análisis de Secuencia por Matrices de Oligonucleótidos , Fosforilación , Proteínas Proto-Oncogénicas c-akt/metabolismo , ARN Mensajero/metabolismo , Transducción de Señal/genética , Factor A de Crecimiento Endotelial Vascular/genética , Factor A de Crecimiento Endotelial Vascular/metabolismoRESUMEN
Hypoxia is a common environmental stress factor and is also associated with various physiological and pathological conditions such as fibrogenesis. The activation of hepatic stellate cells (HSCs) is the key event in the liver fibrogenesis. In this study, the behavior of human HSCs LX-2 in low oxygen tension (1% O2) was analyzed. Upon hypoxia, the expression of HIF-1alpha and VEGF gene was induced. The result of Western blotting showed that the expression of alpha-SMA was increased by hypoxic stimulation. Furthermore, the expression of MMP-2 and TIMP-1 genes was increased. Hypoxia also elevated the protein expression of the collagen type I in LX-2 cells. The analysis of TGF-beta/Smad signaling pathway showed that hypoxia potentiated the expression of TGF-beta1 and the phosphorylation status of Smad2. Gene expression profiles of LX-2 cells induced by hypoxia were obtained by using cDNA microarray technique.
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Regulación de la Expresión Génica , Hígado/citología , Hígado/metabolismo , Factor de Crecimiento Transformador beta/metabolismo , Anaerobiosis/genética , Perfilación de la Expresión Génica , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Metaloproteinasa 2 de la Matriz/genética , Análisis de Secuencia por Matrices de Oligonucleótidos , ARN Mensajero/análisis , ARN Mensajero/metabolismo , Transducción de Señal , Inhibidor Tisular de Metaloproteinasa-1/genética , Factor de Crecimiento Transformador beta1/genética , Factor A de Crecimiento Endotelial Vascular/genéticaRESUMEN
Decorin is a small leucine-rich extracellular matrix proteoglycan composed of a core protein with a single glycosaminoglycan (GAG) chain near the N-terminus and N-glycosylated at three potential sites. Decorin is involved in the regulation of formation and organization of collagen fibrils, modulation of the activity of growth factors such as transforming growth factor beta (TGF-beta), and exerts other effects on cell proliferation and behavior. Increasing evidences show that decorin plays an important role in fibrogenesis by regulating TGF-beta, a key stimulator of fibrosis, and by directly modulating the degradation of extracellular matrix (ECM) from activated hepatic stellate cells (HSCs). In this study, the core protein of human decorin was cloned and expressed in Escherichia coli. The purified recombinant human decorin (rhDecorin) significantly inhibited the proliferation of LX-2 cells, a human HSC cell line, stimulated by TGF-beta1. RT-PCR result showed that the expression of metalloproteinase-2 (MMP-2) and tissue inhibitor of metalloproteinase-1 (TIMP-1) were reduced by rhDecorin in LX-2 cells stimulated by TGF-beta1. Furthermore, the protein expression of smooth muscle-alpha-actin (alpha-SMA), collagen type III and phosphorylated Smad2 (p-Smad2) was significantly decreased in the presence of rhDecorin. rhDecorin also reduced fibrillogenesis of collagen type I in a dose-dependent manner. Gene expression profiles of LX-2 cells stimulated by TGF-beta1 in the presence and the absence of rhDecorin were obtained by using cDNA microarray technique and differentially expressed genes were identified to provide further insight into the molecular action mechanism of decorin on LX-2 cells.
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Proteínas de la Matriz Extracelular/farmacología , Hígado/citología , Proteoglicanos/farmacología , Factor de Crecimiento Transformador beta1/antagonistas & inhibidores , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Colágeno Tipo III/metabolismo , Decorina , Proteínas de la Matriz Extracelular/genética , Proteínas de la Matriz Extracelular/metabolismo , Perfilación de la Expresión Génica , Humanos , Hígado/efectos de los fármacos , Metaloproteinasa 2 de la Matriz/genética , Metaloproteinasa 2 de la Matriz/metabolismo , Fosforilación , Proteoglicanos/genética , Proteoglicanos/metabolismo , ARN Mensajero/metabolismo , Proteínas Recombinantes/farmacología , Proteína Smad2/metabolismo , Factores de Tiempo , Inhibidor Tisular de Metaloproteinasa-1/metabolismoRESUMEN
AIM: To study the effect of WeiJia on chronic liver injury using carbon tetrachloride (CCl(4)) induced liver injury animal model. METHODS: Wistar rats weighing 180-220g were randomly divided into three groups: normal control group (Group A), CCl(4) induced liver injury control group (Group B) and CCl(4) induction with WeiJia treatment group (Group C). Each group consisted of 14 rats. Liver damage and fibrosis was induced by subcutaneous injection with 40% CCl(4) in olive oil at 3 mL/kg body weight twice a week for eight weeks for Groups B and C rats whereas olive oil was used for Group A rats. Starting from the third week, Group C rats also received daily intraperitoneal injection of WeiJia at a dose of 1.25 microg/kg body weight. Animals were sacrificed at the fifth week (4 male, 3 female), and eighth week (4 male, 3 female) respectively. Degree of fibrosis were measured and serological markers for liver fibrosis and function including hyaluronic acid (HA), type IV collagen (CIV), gamma-glutamyl transferase (gamma-GT), alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were determined. Alpha smooth muscle actin (alpha-SMA) and proliferating cell nuclear antigen (PCNA) immunohistochemistry were also performed. RESULTS: CCl(4) induction led to the damage of liver and development of fibrosis in Group B and Group C rats when compared to Group A rats. The treatment of WeiJia in Group C rats could reduce the fibrosis condition significantly compared to Group B rats. The effect could be observed after three weeks of treatment and was more obvious after eight weeks of treatment. Serum HA, CIV, ALT, AST and gamma-GT levels after eight weeks of treatment for Group C rats were 58+/-22 microg/L (P<0.01), 57+/-21 microg/L (P<0.01), 47+/-10 U/L (P<0.01), 139+/-13 U/L (P<0.05) and 52+/-21 U/L (P>0.05) respectively, similar to normal control group (Group A), but significantly different from CCl(4) induced liver injury control group (Group B). An increase in PCNA and decrease in alpha-SMA expression level was also observed. CONCLUSION: WeiJia could improve liver function and reduce liver fibrosis which might be through the inhibition of stellate cell activity.