ABSTRACT
Nitrogen (N) and phosphorus (P) addition, either individually or in combination, has been demonstrated to enhance plant productivity in grassland ecosystems. Soil bacterial community, which is the driver of litter decomposition and nutrient cycling, is assumed to control responses of terrestrial ecosystem structure and function to N and P addition. Using a high-throughput Illumina MiSeq sequencing platform, we conducted a 9-year field experiment of N (0, 5, 10, and 20 g N m-2 yr-1) and P (0 and 10 g P m-2 yr-1) additions in the Inner Mongolian steppes to elucidate long-term effects of N and P addition on soil bacterial richness, diversity and composition. We found that N addition reduced the relative abundance of Acidobacteria, Chloroflexi, and Nitrospirae, while increased that of Bacteroides. The results showed that the bacterial biomarker was enriched in P addition treatments, either individually or combined with N addition. Both N and P addition altered the bacterial community structure, while only N addition greatly decreased bacterial richness and diversity. More importantly, we showed that all of these effects were most significant in N3P treatment (20 g N m-2 yr-1 and 10 g P m-2 yr-1), implying that P coupled with a high-level N addition exerted a great influence on soil bacterial community. Structural equation models revealed that N and P addition had a great direct effect on soil bacterial community and an indirect effect on it mainly by changing the litter biomass. Our findings highlighted that severe niche differentiation was induced by P along with a high-level N, further emphasizing the importance of simultaneously evaluating response of soil bacterial community to N and P addition, especially in the context of increasing anthropogenic nutrient additions.
Subject(s)
Ecosystem , Soil , Soil/chemistry , Grassland , Nitrogen/chemistry , Phosphorus , Bacteria/genetics , Soil Microbiology , ChinaABSTRACT
The stoichiometry characteristics of carbon (C), nitrogen (N), and phosphorus (P) is an important indicator of soil quality and ecosystem nutrient limitations. Exploring the effects of land use type and soil depth on soil nutrient stoichiometry can clarify soil nutrient cycling. In this study, we collected soil samples from sites with five different land use types (irrigated cropland, rainfed cropland, sandy grassland, fixed dunes, and mobile dunes) in the Horqin Sandy Land, and evaluated the influences of land use type and soil depth on the contents and stoichiometry characteristics of soil organic carbon (SOC), total nitrogen (TN), and total phosphorus (TP). We found that: 1) SOC (3.23 g·kg-1), TN (0.37 g·kg-1), and TP (0.15 g·kg-1) contents and stoichiometry characteristics (C:N, C:P, N:P was 9.07, 25.56, 2.97, respectively) to a depth of 10 cm in the Horqin Sandy Land were significantly lower than the mean values of soils in China. 2) Soil stoichiometry characteristics differed significantly among land use types. The contents of SOC, TN, and TP to a depth of 100 cm were highest in irrigated cropland, followed by sandy grassland, rainfed cropland, fixed dunes, and mobile dunes. The C:N ratios in sandy grassland, irrigated cropland, and rainfed cropland were significantly higher than those in the fixed dune and mobile dune sites. C:P ratios in the sandy grassland, fixed dunes, irrigated cropland, and rainfed cropland were significantly higher than that in the mobile dunes. The N:P ratio differed little among the five land use types. 3) SOC and TN contents in the sandy grassland, fixed dunes, irrigated cropland, and rainfed cropland decreased with increasing soil depth. SOC, TN, and C:P in the mobile dunes and TP and C:N in all land use types showed no variation among depths. The C:P ratio of sandy grassland, fixed dunes, irrigated cropland, and rainfed cropland and the N:P ratio of sandy grassland decreased with increasing soil depth. 4) SOC, TN, and TP contents and the C:N ratio were significantly negatively correlated with the contents of medium and fine sands and with soil bulk density, but significantly positively correlated with silt+clay, and very fine sand contents. Desertification led to losses of SOC and nutrients in the Horqin Sandy Land, and exacerbated soil N deficiency. Inputs of water and ferti-lizer helped cropland to maintain a relatively high level of soil nutrients.
Subject(s)
Ecosystem , Soil , Sand , Carbon/analysis , China , Nitrogen/analysis , PhosphorusABSTRACT
OBJECTIVE: To investigate the mechanism of inflflammatory-mediated toll-like receptor 4 (TLR4)-p38 mitogen-activated protein kinase (p38 MAPK) pathway in Kupffer cells (KCs) of non-alcoholic steatohepatitis (NASH) rats and the intervention effect of soothing Gan (Liver) and invigorating Pi (Spleen) recipes on this pathway. METHODS: After 1 week of acclimatization, 120 Sprague-Dawley male rats were randomly divided into 8 groups using a random number table (n=15 per group): normal group, model group, low-dose Chaihu Shugan Powder (, CHSG) group (3.2 g/kg), high-dose CHSG group (9.6 g/kg), low-dose Shenling Baizhu Powder (, SLBZ) group (10 g/kg), high-dose SLBZ (30 g/kg) group, and low- and highdose integrated recipe (L-IR, H-IR) groups. All rats in the model and treatment groups were fed with a high-fat diet (HFD). The treatments were administrated by gastrogavage once daily and lasted for 26 weeks. The liver tissues were detected with hematoxylin-eosin (HE) and oil red O staining. Levels of liver lipids, serum lipids and transaminases were measured. KCs were isolated from the livers of rats to evaluate the mRNA expressions of TLR4 and p38 MAPK by real-time flfluorescence quantitative polymerase chain reaction, and proteins expressions of TLR4, p-p38 MAPK and p38 MAPK by Western blot. Levels of inflammatory cytokines including tumor necrosis factor α (TNF-α), interleukin (IL)-1 and IL-6 in KCs were measured by enzyme-linked immunosorbent assay. RESULTS: After 26 weeks of HFD feeding, HE and oil red O staining showed that the NASH model rats successfully reproduced typical pathogenesis and histopathological features. Compared with the normal group, the model group exhibited significant increases in body weight, liver weight, liver index, serum levels of total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol, and aspartate aminotransferase as well as TC and TG levels in liver tissues, and significant decrease in serum level of high-density lipoprotein cholesterol (Plt;0.05 or Plt;0.01), while those indices were significantly ameliorated in the H-IR group (Plt;0.05 or Plt;0.01). Higher levels of TNF-α, IL-1 and IL-6 in KCs were observed in the model group compared with the normal group (Plt;0.01). Significant decreases in TNF-α, IL-1 and IL-6 were observed in the H-SLBZ, H-IR and L-IR groups compared with the model group (Plt;0.05 or Plt;0.01). The mRNA expressions of TLR4 and p38 MAPK and protein expressions of TLR4, p38 MAPK and p-p38 MAPK in KCs in the model group were significantly higher than the normal group (Plt;0.01), while those expression levels in the L-IR and H-IR groups were significantly lower than the model group (Plt;0.05 or Plt;0.01). CONCLUSION: Inflflammation in KCs might play an important role in the pathogenesis of NASH in rats. The data demonstrated the importance of TLR4-p38MAPK signaling pathway in KCs for the anti-inflflammatory effect of soothing Gan and invigorating Pi recipes.
Subject(s)
Drugs, Chinese Herbal/pharmacology , Kupffer Cells/drug effects , MAP Kinase Signaling System/drug effects , Medicine, Chinese Traditional , Non-alcoholic Fatty Liver Disease/drug therapy , Plant Extracts/pharmacology , Signal Transduction/drug effects , Toll-Like Receptor 4/physiology , p38 Mitogen-Activated Protein Kinases/physiology , Animals , Kupffer Cells/physiology , Male , Non-alcoholic Fatty Liver Disease/physiopathology , Rats , Rats, Sprague-DawleyABSTRACT
OBJECTIVE: To investigate effects of the extracts from soothing-liver and invigorating-spleen formulas on the injury due to oxidative stress, mediated by the Nuclear factor-like 2 (Nrf2)-Antioxidant response element (ARE) pathway, in the hepatocytes of rats with non-alcoholic fatty liver disease (NAFLD) induced by high-fat diet. METHODS: Soothing-liver and invigorating-spleen formula mixtures were prepared for five groups: normal, model, soothing-liver formula group (SLG), invigorating-spleen formula group (ISG), integrated formula group (IG). The rat model of NAFLD was induced by feeding rats a high-fat diet (HFD). After 16 weeks, the hepatic tissue was examined following Haematoxylin-Eosin (H&E) staining and with Transmission electron microscopy (TEM). Levels of hepatic lipids, serum lipids and hepatic functions were measured using a biochemical analyser. Hepatocytes were isolated from the livers of rats and were identified by cellar immunohistochemistry, cellular immunofluorescence and flow cytometry. The expression levels of Nrf2, Kelch-like epichlorohydrin-associated protein 1 (Keap-1), haeme oxygenase-1 (HO-1) and NAD(P)H: quinone oxidoreductase 1 (NQO1) mRNAs were assessed by real-time fluorescence quantitative PCR. Nrf2, Keap-1, HO-1 and NQO1 proteins were measured by Western blotting. Finally, the levels of oxidative stress factors Superoxide Dismutase (SOD), malonaldehyde (MDA) and Glutathione peroxidase (GSH-Px) in hepatocytes were measured by WST-1, TBA and colorimetry. RESULTS: The H & E and TEM results showed that the NAFLD model rats successfully reproduced typical pathogenetic and histopathological features. The liver function and levels of hepatic lipids and serum lipids from the model rats were dramatically increased. Compared with the model group, the levels of hepatic lipids, serum lipids and hepatic function in the treatment groups were ameliorated to different degrees. The yields of purified hepatocytes in each rat were 4-5 ¡Á 108. The viability of the isolated hepatocytes was higher than 95%, with a purity over 93.2%. Cellular immunohistochemistry analysis showed that the hepatocytes were brown, while in the cellular immunofluorescence analysis, the hepatocytes showed green fluorescence. The expression levels of Nrf2, Keap-1, HO-1 and NQO1 mRNA and protein in the hepatocytes were significantly higher in the model group than in the normal group (P < 0.05, P < 0.01). Compared with the model group, the expression of Nrf2, Keap-1, HO-1 and NQO-1 mRNAs and proteins in all treatment groups increased, especially in the IG (P < 0.01). CONCLUSION: The extracts from soothing-liver and invigorating-spleen formulas may protect the liver against the injury induced by oxidative stress in hepatocytes by influencing the Nrf2-ARE pathway, which may be the mechanism having the potential for prevention and treatment of NAFLD.
ABSTRACT
This study investigates the effect of soothing liver and invigorating spleen recipes on steatohepatitis examining the IKKß-NF-κB signaling pathway in KCs of NASH rats. SD male rats were randomly divided into 8 groups, and the NASH model was induced by a high-fat diet (HFD). After 26 weeks, liver tissue was examined in H&E stained sections and liver function was monitored biochemically. KCs were isolated by Seglen's method, with some modifications. The mRNA and protein expression of the IKKß-NF-κB signaling pathway components was examined by quantitative PCR and Western blotting. The results show that the high-fat diet induced NASH in the rats, and the soothing liver recipe and invigorating spleen recipe decreased the levels of TNF-α, IL-1, and IL-6 in KCs, as well as inhibiting the mRNA and protein expression of the IKKß-NF-κB signaling pathway components. In conclusion, the experiment indicated the importance of the IKKß-NF-κB signaling pathway in KCs for the anti-inflammatory effects of the soothing liver and invigorating spleen recipes.
ABSTRACT
OBJECTIVE: To explore the effect of berberine on lipid metabolism disorder and lipid deposition in liver cells of non-alcoholic fatty liver disease (NAFLD) rats induced by high fat diet. METHODS: After one week adaptable feeding, 45 SPF level male SD rats were randomly divided into 3 groups, the normal control group, the model group, and the berberine group, 15 in each group. Except those in the normal control group, all rats were fed with high fat diet to prepare NAFLD model. As for rats in the berberine group, Berberine Hydrochloride was administered by gastrogavage. HE staining and oil red O staining were performed to identify the model after 8 weeks. Hepatocytes were isolated, and their activities and purities were tested by Typan blue staining and flow cytometry (FCM). Serum levels of TC, TG, HDL-C, and LDL-C were detected using automatic biochemical analyzer. mRNA expression levels of LXRα and FAS in liver cells were analyzed by Real-time quantitative polymerase chain reaction (PCR). Protein levels of LXRα and FAS in liver cells were examined by Western blot. RESULTS: The NAFLD rat model was successfully established by high fat diet. The yields of purified liver cells in each rat were (6.0-7.5) x 10(8). The viability of isolated liver cells with purity over 90% (tested by FCM analysis) was higher than 95%. Compared with the normal control group,the expression of LXRα and FAS at mRNA and protein levels was higher in the model group (P < 0.01). Compared with the model group, the expression of LXRα and FAS at mRNA and protein levels was obviously down-regulated in the berberine group (P < 0.01). CONCLUSIONS: LXRα/FAS signaling pathway was one of important signaling pathways of NAFLD lipid metabolism disorders. Berberine could recover hepatocyte fatty deposits in NAFLD rats by adjusting the LXR/FAS signaling pathway of hepatocytes, which might be one of important mechanisms for fighting against NAFLD.
Subject(s)
Berberine/therapeutic use , Diet, High-Fat , Drugs, Chinese Herbal/therapeutic use , Non-alcoholic Fatty Liver Disease/drug therapy , Animals , Down-Regulation , Fatty Liver , Hepatocytes , Lipids , Male , RNA, Messenger , Rats , Rats, Sprague-Dawley , Signal TransductionABSTRACT
Two new bufadienolide glycosides (1 and 2) with an A/B trans ring fusion together with nine known compounds (3-11) were isolated from the rhizomes of Helleborus thibetanus. The structures of new compounds were elucidated by extensive spectroscopic analyses in combination with single-crystal X-ray diffraction. The bufadienolides 1 and 3-6 exhibited potent cytotoxic activities against the prostate cancer cells.
Subject(s)
Antineoplastic Agents, Phytogenic/isolation & purification , Antineoplastic Agents, Phytogenic/pharmacology , Bufanolides/isolation & purification , Bufanolides/pharmacology , Drugs, Chinese Herbal/isolation & purification , Drugs, Chinese Herbal/pharmacology , Glycosides/isolation & purification , Glycosides/pharmacology , Helleborus/chemistry , Prostatic Neoplasms/drug therapy , Antineoplastic Agents, Phytogenic/chemistry , Bufanolides/chemistry , Crystallography, X-Ray , Drug Screening Assays, Antitumor , Drugs, Chinese Herbal/chemistry , Glucosides , Glycosides/chemistry , Humans , Male , Molecular Conformation , Molecular Structure , Rhizome/chemistryABSTRACT
BACKGROUND: Traditional Chinese Medicine (TCM), has over thousands-of-years history of use. Chaihu-Shugan-San (CSS), and Shen-ling-bai-zhu-San (SLBZS), are famous traditional Chinese herbal medicine formulas, which have been used in China, for the treatment of many chronic diseases. MATERIALS AND METHODS: This study investigated the anti-inflammatory effects of CSS and SLBZS on signaling molecules involved in p38 mitogen-activated protein kinase (p38 MAPK), pathway on hepatocytes of non-alcoholic steatohepatitis (NASH), rats induced by high fat diet. SD male rats were randomly divided into 8 groups: negative control group, model control group, high (9.6g/kg/day)/low (3.2g/kg/day)-dose CSS group, high (30g/kg/day)/low (10g/kg/day)-dose SLBZS group, high (39.6g/kg/day)/low (13.2g/kg/day)-dose integrated group. The rats of NASH model were induced by feeding a high-fat diet. After 16, wks, Hepatocytes were isolated from 6, rats in each group by collagenase perfusion. The liver histopathological changes and serum inflammatory cytokines TNF-α, IL-6 were determined. The proteins of TLR4, phosphor-p38 MAPK and p38 MAPK involved in p38 MAPK signal pathway were assayed. RESULTS: The statistical data indicated the NASH model rats reproduced typical histopathological features of NASH in human. CSS and SLBZS ameliorated lipid metabolic disturbance, attenuated NASH progression, decreased the levels of TNF-α and IL-6 in serum, as well as inhibited TLR4 protein expression, p38 MAPK phosphorylation, and activation of p38 MAPK. In conclusion, CSS and SLBZS might work as a significant anti-inflammatory effect on hepatocyte of NASH by inhibiting the activation of TLR4, p-p38 MAPK and p38 MAPK involved in p38 MAPK signal pathway. CONCLUSION: To some extent, CSS and SLBZS may be a potential alternative and complementary medicine to protect against liver injury, alleviate the inflammation reaction, moderate NASH progression.
Subject(s)
Anti-Inflammatory Agents/therapeutic use , Drugs, Chinese Herbal/therapeutic use , Fatty Liver/drug therapy , Lipid Metabolism/drug effects , Liver/drug effects , Phytotherapy , p38 Mitogen-Activated Protein Kinases/metabolism , Animals , Anti-Inflammatory Agents/pharmacology , Diet, High-Fat , Drugs, Chinese Herbal/pharmacology , Fatty Liver/etiology , Fatty Liver/metabolism , Hepatocytes/drug effects , Hepatocytes/metabolism , Interleukin-6/blood , Liver/metabolism , Magnoliopsida , Male , Non-alcoholic Fatty Liver Disease , Phosphorylation , Plant Extracts/pharmacology , Plant Extracts/therapeutic use , Random Allocation , Rats , Rats, Sprague-Dawley , Signal Transduction , Toll-Like Receptor 4/metabolism , Tumor Necrosis Factor-alpha/bloodABSTRACT
OBJECTIVE: To explore the effects of soothing liver and invigorating spleen recipes on lipopolysaccharide(LPS) induced hepatocyte inflammation of rats and TLR4/p38MAPK signal pathway. METHOD: The hepatocytes of SD rats were cultured and identified in vitro. The medicated serum of soothing liver and invigorating spleen recipes was prepared. The hepatocytes were treated with soothing liver and invigorating spleen recipes. Then Interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) expression in cultural supernatants were assayed by ELISA. The expressions of Toll-Like 4 (TLR4), p38 mitogen activated protein kinases (p38MAPK) and p-p38 mitogen-activated protein kinase (p-p38MAPK) were detected by Western blot. RESULT: The rat medicated serum of soothing liver and invigorating spleen recipes was extracted for 2-3 mL. The purified rat hepatocytes were 1.5 x 10(8)-2.0 x 10(8). The cell viability was above 95% detected by Typan blue staining. The hepatocytes were identified by immumofluorescence assay. The detection of hepatocyte cultural supernatants: compared with that of the control group, IL-6 and TNF-α expression were increased in the LPS group (P < 0.01). While compared with that of the LPS group, the expressions of IL-6 and TNF-α were decreased after soothing liver and invigorating spleen recipes intervention (P < 0.01). The detection of hepatocyte proteins: compared with that of the control group, the protein expressions of p38MAPK, p-p38MAPK and TLR4 were all increased significantly in the LPS group (P < 0.01). Compared with that of the LPS group, the protein expressions of p38MAPK was decreased significantly in SB239063 group and it was also decreased in the soothing liver and invigorating spleen recipes group, but with no significant difference. Compared with that of the LPS group, p38MAPK expression was reduced significantly in the soothing liver and invigorating spleen recipes group and the SB239063 (p38MAPK pathway inhibitor) group (P < 0.01). TLR4 protein expression was decreased markedly in the soothing liver and invigorating spleen recipes group (P < 0.01) but had no difference between the SB239063 group and the LPS group. CONCLUSION: The soothing liver and invigorating spleen recipes may regulate hepatocyte inflammatory injury of rats through TLR4/p38MAPK signaling pathway.
Subject(s)
Drugs, Chinese Herbal/administration & dosage , Hepatocytes/drug effects , Liver/drug effects , Non-alcoholic Fatty Liver Disease/drug therapy , Spleen/drug effects , Toll-Like Receptor 4/metabolism , p38 Mitogen-Activated Protein Kinases/metabolism , Animals , Female , Hepatocytes/metabolism , Humans , Lipopolysaccharides/adverse effects , Liver/injuries , Liver/metabolism , Male , Non-alcoholic Fatty Liver Disease/genetics , Non-alcoholic Fatty Liver Disease/metabolism , Rats , Rats, Sprague-Dawley , Signal Transduction/drug effects , Spleen/metabolism , Toll-Like Receptor 4/genetics , p38 Mitogen-Activated Protein Kinases/geneticsABSTRACT
OBJECTIVE: To explore the effect of Shugan Jianpi Recipe (SJR) on LXRα/FAS signaling pathway mediated hepatocyte fatty deposits in nonalcoholic fatty liver disease (NAFLD) rats. METHODS: Totally 75 SPF grade male SD rats were randomly divided into 5 groups, i.e., the normal control group, the model group, the Shugan Recipe (SR) treatment groups, the Jianpi Recipe (JR) treatment group, and the SJR group. Except rats in the normal control group, the NAFLD rat model was duplicated using high fat diet (HFD). SR (Chaihu Shugan Powder) was administered to rats in the SR group. JR (Shenlin Baizhu Powder) was administered to rats in the JR group. SJR (Chaihu Shugan Powder plus Shenlin Baizhu Powder) was administered to rats in the SJR group. Changes of liver fat were analyzed using automatic biochemical analyzer. Liver cells were separated by low-speed centrifugation. Their activities and purities were identify using Typan blue and flow cytometry (FCM). Expression levels of LXRα and FAS mRNA in hepatocytes detected by Real-time quantitative PCR. Expression levels of LXRα and FAS protein were detected by Western blot. RESULTS: (1) Pathological results showed in the model group, hepatocytes were swollen with nucleus locating at the cell edge after oil red O staining; unequal sized small vacuoles could be seen inside cytoplasm. Some small vacuoles merged big vacuoles. All these indi- cated a NAFLD rat model was successfully established by high fat diet. Pathological structural changes could be impaired to some degree in all medicated groups, especially in the SR group. (2) Compared with the normal control group, expression levels of LXRα and FAS genes and proteins obviously increased in the model group (P < 0.01). Compared with the model group, their expression levels were obviously down-regulated in the JR group and the SR group (P < 0.01, P < 0.05). CONCLUSIONS: LXRα/FAS signaling pathway was an important signaling pathway for mediating lipid metabolism disorders of NAFLD rats. SJR could make hepatocyte fatty deposits tend to repair by adjusting the LXRα/FAS signaling pathway in NAFLD rats, which might be one of important mechanisms for SJR to prevent and cure NAFLD.