Variation and interaction mechanism between active components in Rheum officinale and rhizosphere soil microorganisms under drought stress / 中国中药杂志

To explore the changes and the reaction mechanisms between soil microecological environment and the content of secon-dary metabolites of plants under water deficit, this study carried out a pot experiment on the 3-leaf stage seedlings of Rheum officinale to analyze their response mechanism under different drought gradients(normal water supply, mild, moderate, and severe drought). The results indicated that the content of flavonoids, phenols, terpenoids, and alkaloids in the root of R. officinale varied greatly under drought stresses. Under mild drought stress, the content of substances mentioned above was comparatively high, and the content of rutin, emodin, gallic acid, and(+)-catechin hydrate in the root significantly increased. The content of rutin, emodin, and gallic acid under severe drought stress was significantly lower than that under normal water supply. The number of species, Shannon diversity index, richness index, and Simpson index of bacteria in the rhizosphere soil were significantly higher than those in blank soil, and the number of microbial species and richness index decreased significantly with the aggravation of drought stresses. In the context of water deficit, Cyanophyta, Firmicutes, Actinobacteria, Chloroflexi, Gemmatimonadetes, Streptomyces, and Actinomyces were the dominant bacteria in the rhizosphere of R. officinale. The relative content of rutin and emodin in the root of R. officinale was positively correlated with the relative abundance of Cyanophyta and Firmicutes, and the relative content of(+)-catechin hydrate and(-)-epicatechin gallate was positively correlated with the relative abundance of Bacteroidetes and Firmicutes. In conclusion, appropriate drought stress can increase the content of secondary metabolites of R. officinale from physiological induction and the increase in the association with beneficial microbe.

Effect of endothelial progenitor cell on hematopoietic reconstitution in allogeneic hematopoietic stem cell transplantation mouse model / 中华血液学杂志

<p><b>OBJECTIVE</b>To examine the effects of endothelial progenitor cell (EPC) on hematopoietic reconstitution in allogeneic hematopoietic stem cell transplantation (allo-HSCT) mouse model.</p><p><b>METHODS</b>Allo-HSCT mouse model was established with condition of BU/CY, in which C57BL/6 (H-2b) and BALB/c (H-2d) mice were used as donors and recipients respectively. Recipients were randomly divided into 4 groups: untreated group, BU/CY condition group, bone marrow transplantation (BMT) group and transplantation of BM cells combined with EPCs (combined transplantation) group. The pathological changes of BM cells following transplantation were dynamically observed. Changes of BM sinusoidal endothelium and angiogenesis were observed by MECA-32 antibody immunohistochemical staining. The proportion of intramedullary stem and progenitor cells and serum cytokines were analyzed by flow cytometry. The numbers of peripheral blood cells were also counted.</p><p><b>RESULTS</b>(1) Injuries of BM hematopoietic tissue, sinusoidal endothelium and vascular were less severe in combined transplantation group than of BMT group. (2) EPC infusion significantly increased BM hematopoietic stem cells 21 days after transplantation. The percentage of BM hematopoietic stem cells in combined transplantation group peaked on day +14, which was higher than of BMT group (0.1743 vs 0.0787) (P<0.05). The continuously increased percentage of BM hematopoietic progenitor cells in combined transplantation group was significantly higher than in BMT group on day +21 (0.4550 vs 0.3905) (P<0.05). (3) The number of peripheral white blood cells in combined transplantation group was always higher than of BMT group, which reached the peak on day +14 (0.74×10⁹/L to 0.47×10⁹/L) (P<0.05). The peak number of peripheral blood platelets on day +14 in combined transplantation group was significantly higher than of group BMT (1228.9×10⁹/L to 977.12×10⁹/L) (P<0.05).</p><p><b>CONCLUSION</b>Allo-HSCT combined with EPC infusion accelerated hematopoietic reconstitution compared with BMT alone in allo-HSCT mouse model.</p>

Effects of liver sinusoid endothelial cell injury in mouse hepatic veno-occlusive disease / 中国实验血液学杂志

This study was purposed to investigate the role of monocrotaline-inducing mouse liver sinusoid endothelial cell (SEC) injury in hepatic veno-occlusive disease. BALB/c mice were randomly divided into 2 groups: control group and monocrotaline group, mice were orally administrated with normal saline or monocrotaline with concentration of 200 mg/kg at days 0, 1, 2, respectively. At days 3, 4, 6, 8 and 10 after oral administration with normal saline or monocrotaline, the liver function (ALT, TBIL, AKP) and liver index were examined, and the percentage of activated platelets were detected by flow cytometry. The SEC, vascular endothelial cells and hepatic fibrosis were observed by staining with hematoxylin-eosin and Masson. Transmission electron microscopy was used to observe sinusoidal endothelial cell damage and platelet adhesion. The results showed that compared with control group, mice in monocrotaline group were characterized by severe damage of SEC, numbers of platelet aggregation and adhesion, central number and sinusoidal fibrosis. The percentage of activated platelets and liver index increased (P < 0.05). The characterization of portal hypertension was presented later, such as dysfunction of liver and ascites. It is concluded that SEC injury induced by monocrotaline may be the first step of hepatic veno-occlusive disease, and this kind of SEC injury is self-limiting, but fibrosis is always observed.