Transcriptomic and physiological analysis reveals interplay between salicylic acid and drought stress in citrus tree floral initiation.

MAIN CONCLUSION: Salicylic acid (SA) and drought stress promote more flowering in sweet orange. The physiological response and molecular mechanism underlying stress-induced floral initiation were discovered by transcriptome profiling. Numerous flowering-regulated genes were identified, and ectopically expressed CsLIP2A promotes early flowering in Arabidopsis. Floral initiation is a critical developmental mechanism associated with external factors, and citrus flowering is mainly regulated by drought stress. However, little is known about the intricate regulatory network involved in stress-induced flowering in citrus. To understand the molecular mechanism of floral initiation in citrus, flower induction was performed on potted Citrus sinensis trees under the combined treatment of salicylic acid (SA) and drought (DR). Physiological analysis revealed that SA treatment significantly normalized the drastic effect of drought stress by increasing antioxidant enzyme activities (SOD, POD, and CAT), relative leaf water content, total chlorophyll, and proline contents and promoting more flowering than drought treatment. Analysis of transcriptome changes in leaves from different treatments showed that 1135, 2728 and 957 differentially expressed genes (DEGs) were revealed in response to DR, SD (SA + DR), and SA (SA + well water) treatments in comparison with the well watered plants, respectively. A total of 2415, 2318 and 1933 DEGs were expressed in DR, SD, and SA in comparison with water recovery, respectively. Some key flowering genes were more highly expressed in SA-treated drought plants than in DR-treated plants. GO enrichment revealed that SA treatment enhances the regulation and growth of meristem activity under drought conditions, but no such a pathway was found to be highly enriched in the control. Furthermore, we focused on various hormones, sugars, starch metabolism, and biosynthesis-related genes. The KEGG analysis demonstrated that DEGs enriched in starch sucrose metabolism and hormonal signal transduction pathways probably account for stress-induced floral initiation in citrus. In addition, a citrus LIPOYLTRANSFERSAE 2A homologous (LIP2A) gene was upregulated by SD treatment. Ectopic expression of CsLIP2A exhibited early flowering in transgenic Arabidopsis. Taken together, this study provides new insight that contributes to citrus tree floral initiation under the SA-drought scenario as well as an excellent reference for stress-induced floral initiation in woody trees.

Andrographolide as an anti-H1N1 drug and the mechanism related to retinoic acid-inducible gene-I-like receptors signaling pathway.

OBJECTIVE: To observe the anti-virus effects of andrographolide (AD) on the retinoic acid-inducible gene-I (RIG-I)-like receptors (RLRs) signaling pathway when immunological cells were infected with H1N1. METHODS: Leukomonocyte was obtained from umbilical cord blood by Ficoll density gradient centrifugation, and immunological cells were harvested after cytokines stimulation. Virus infected cell model was established by H1N1 co-cultured with normal human bronchial epithelial cell line (16HBE). The optimal concentration of AD was defined by methyl-thiazolyl-tetrazolium (MTT) assay. After the virus infected cell model was established, AD was added into the medium as a treatment intervention. After 24-h co-culture, cell supernatant was collected for interferon gamma (IFN-γ) and interleukin-4 (IL-4) enzyme-linked immunosorbent assay (ELISA) detection while immunological cells for real-time polymerase chain reaction (RT-PCR). RESULTS: The optimal concentration of AD for anti-virus effect was 250 µg/mL. IL-4 and IFN-γ in the supernatant and mRNA levels in RLRs pathway increased when cells was infected by virus, RIG-I, IFN-ß promoter stimulator-1 (IPS-1), interferon regulatory factor (IRF)-7, IRF-3 and nuclear transcription factor κB (NF-κB) mRNA levels increased significantly (P<0.05). When AD was added into co-culture medium, the levels of IL-4 and IFN-γ were lower than those in the non-interference groups and the mRNA expression levels decreased, RIG-I, IPS-1, IRF-7, IRF-3 and NF-κB decreased significantly in each group with significant statistic differences (P<0.05). CONCLUSIONS: The RLRs mediated viral recognition provided a potential molecular target for acute viral infections and andrographolide could ameliorate H1N1 virus-induced cell mortality. And the antiviral effects might be related to its inhibition of viral-induced activation of the RLRs signaling pathway.

The inducible effect of LBP on maturation of dendritic cells and the related immune signaling pathways in hepatocellular carcinoma (HCC).

OBJECTIVE: To investigate the effect of LBP on differentiation and maturation of healthy human peripheral blood-derived dendritic cells cultured in different tumor microenvironment in vitro, and discuss the molecular and immunological mechanisms of LBP in treatment of tumor. METHODS: In this study, we procured the peripheral blood-derived dendritic cells precursor cell by the Density gradient centrifugation method, and used the tumor-cell supernatant to prepare conditioned medium. The GM-CSF and IL-4 induced DCs precursor cell differentiation to DCs, the TNF-α promoted the immature DCs developed to mature DCs. In this way, we detected the influence of LBP on the expressions of surface molecules of DCs cultured in different environments, and especially on the role of related-immunity and NF-κB activity. RESULTS: In LBP-treated group, the molecular phenotype of DCs, its capacity to stimulate allogeneic lymphocyte proliferation, and the levels of IL-12p70 and IFN-γ secretion were higher than the untreated group (p < 0.05), with statistical significance. Meanwhile the expression of NF-κB of the DCs in the medium treated by the LBP was higher than the untreated group (p < 0.05), also with statistical significance. Between the two different tumor microenvironment groups, the cell nucleus protein NF-κB expression is obviously different, the hepG2.2.15 group higher than the hepG2 group. CONCLUSION: LBP could increase the expression of the phenotype of DCs, the secretion of IL-12p70 and IFN-γ in MLR, and enhance the NF-κB expression, especially in the virus-related group, suggesting LBP plays the anti-tumor role stronger in the virus-related environment and this phenomenon correlates with the NF-κB signaling pathway.

Study on the protective effect of shengmai san (see text) on the myocardium in the type 2 diabetic cardiomyopathy model rat.

OBJECTIVE: To study the effect of Shengmai San ((see text) Pulse-activating Powder) in protecting myocardium in the rat of the type 2 diabetic cardiomyopathy (DCM) model. METHODS: The DCM rat model was established by combination of insulin resistance induced by a high-fat diet with intraperitoneal injection of high dose streptozotocin (50 mg/kg). And these rat models were randomly divided into three groups: a normal group (n = 12,one of them died), a model group (n = 15) and a Shengmai San group (treatment group, n = 15).The damage of the myocardium was assessed by electrocardiogram at the twelfth week after modeling, and the blood glucose, cholesterol and triglyceride levels were determined; the content of the left cardiac ventricle myocardial collagen was quantified by Masson staining test; the level of myocardial cell apoptosis was detected with TUNEL apoptosis detection kit; the damage extent of the myocardial sub-cellular structures was observed by electron microscopy; the expression levels of cardiac TSP-1 (Thrombospondin-1), TGF-beta1 (Transforming Growth F factor-beta) and TRB-3 (Tribbles homolog 3) proteins were detected by immunohistochemical method; the expression levels of cardiac TSP-1, A-TGF-beta1 and L-TGF-beta1 proteins were detected by Western blotting; and the expression levels of TSP-1 and TRB-3 mRNAs were detected by real-time quantitative PCR. RESULTS: Compared with the control group, the blood glucose, cholesterol, triglycerides levels in both the model groups and the Shengmai San group were significantly decreased; the myocardial tissue was less damaged and the collagen content was reduced in the Shengmai San group; the myocardial sub-cellular structure was injured to a lesser extent; the expression levels of myocardial TSP-1, TGF-beta1, TRB-3, and TSP-1, A-TGF-beta1, L-TGF-beta1 and chymase were decreased, and the expression levels of TSP-1 mRNA and TRB-3 mRNA were decreased in both the model groups and the Shengmai San group (the latter was better),. CONCLUSION: Shengmai San can inhibit myocardial fibrosis in the rat of diabetic cardiomyopathy, and significantly delay the formation of diabetic cardiomyopathy in hyperglycemia rats through multiple pathways.

Protective effects on myelosuppression mice treated by three different classic Chinese medicine formulae.

BACKGROUND: In order to observe the protective therapeutic action and mechanism of Liuwei Dihuang Decoction, Buzhong Yiqi Decoction, and Compound Danshen Decoction on Myelosuppression induced by cyclophosphamide. MATERIALS AND METHODS: The mice model was established by intraperitoneal injected with 100 mg/kg cyclophosphamide by human and mice dose conversion on the 9(th), 11(th), 13(th) days during the experiment. Flow cytometry (FCM) was used for detecting the number of cells and investigating bone marrow cell cycles. Spleen was taken out and the mRNA expression level of thrombopoietin (TPO) and c-Mpl were detected by Q-PCR, and c-Mpl in spleen in order to discuss the mechanism of myelosuppression and the protective effects of traditional Chinese medicine. RESULTS: Both Liuwei Dihuang Decoction Group and Buzhong Yiqi Decoction Group can accelerate bone marrow hematopoietic stem progenitor cells (HSPCs) in marrow-suppressed mice and enhance cell proliferation by promoting cell cycles from G0/G1 phase to access into S, G2/M phase. And at the same time these Chinese decoctions can increase the mRNA expression level of TPO and c-Mpl in spleen. CONCLUSION: Researched showed that Chinese formula take effect by affecting these genes on myelosuppressed mice.

Study on the protective effect of the Mixture of Shengmai Powder and Danshen Decoction on the myocardium of diabetic cardiomyopathy in the rat model.

OBJECTIVE: To study the protective effect of the Mixture of Shengmai Powder and Danshen Decoction (, abbreviated as the Mixture) in the rat model with type 2 diabetic cardiomyopathy in the rat model with type 2 diabetic cardiomyopathy, abbreviated as the Mixture) in the rat model with type 2 diabetic cardiomyopathy (DCM). METHODS: Forty-two SD rats with DCM model, established by the combination of insulin resistance by a high-fat diet with the damage of pancreatic islet ß cells by intraperitoneal injection of high dose streptozotocin (50 mg/kg) once, were evaluated in the damage of the myocardium by electrocardiogram at the end of 12 weeks of grouping and intervention administration; the extent of damage in the myocardial subcellular structure was observed by electron microscopy; the content of myocardial collagen in the left cardiac ventricle was quantified by Masson staining test; the myocardial cell apoptosis was determined by TUNEL; the changes in the mRNA expression levels of thrombospodin-1 (TSP-1) and tribbles homolog 3 (TRB-3) by real-time quantitative PCR, the expression levels of myocardial TSP-1, tumor growth factorß1 (TGF-ß1), TRB-3, and chymase were detected by immunohistochemistry, and the changes in the expression levels of myocardial TSP-1, active-TGF-ß1 (A-TGF-ß1) and latent-TGF-ß1 (L-TGF-ß1) protein were tested by Western blotting. RESULTS: Compared with the control group, the myocardial tissue was less damaged, and the extent of damage in the myocardial subcellular structure was less; the collagen fiber content and the cell apoptosis were reduced; the expression levels of TSP-1mRNA and TRB-3 mRNA, the expression levels of myocardial TSP-1, TGF-ß1, TRB-3, and chymase, as well as the average expression levels of the myocardial TSP-1, A-TGFß1, and L-TGF-ß1 protein were decreased in the Mixture group. CONCLUSION: The Mixture of Shengmai Powder and Danshen Decoction could inhibit the process of myocardial fibrosis in the rat myocardium of DCM through multiple pathways and significantly delay the genesis and progress of DCM in hyperglycemic rats.