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Long non‐coding RNAs (lncRNAs) have been identified as playing critical roles in multiple diseases. However, little is known regarding their roles and mechanisms in post‐stroke angiogenesis. Our studies focused on deciphering the functional roles and the underlying mechanisms of the lncRNA metastasis‐associated lung adenocarcinoma transcript 1 (MALAT1) in the process of angiogenesis following oxygen‐glucose deprivation/reoxygenation (OGD/R). We characterized the up‐regulation of MALAT1 expression in the process of angiogenesis after hypoxic injury in vivo and in vitro. We further showed that compared with the empty vector, MALAT1 knockdown had significantly reduced the capacity for angiogenesis, which was measured by 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium (MTT), scratching, cell cycle and immunofluorescent staining. Thus, our findings suggest that MALAT1 may mediate proangiogenic function in OGD/R. To further explore the potential mechanisms, we used lentiviruses expressing shMALAT1 and empty vector; the results revealed that shMALAT1 reduced the expression of 15‐lipoxygenase 1 (15‐LOX1), vascular endothelial growth factor (VEGF) and the phosphorylation of signal transducers and activators of transcription 3 (pSTAT3). Taken together, our results are the first to propose that MALAT1 may regulate angiogenesis through the 15‐LOX1/STAT3 signalling pathway, and they may provide a critical target for the treatment of hypoxic injury and an avenue for therapeutic angiogenesis.

Background The mechanism by which vascular regeneration declines with aging is not fully understood. An interaction between integrin and vascular endothelial growth factor receptor-2 (VEGFR-2) plays a substantial role in angiogenesis. Here, we investigated whether aging impairs this interaction in endothelial progenitor cells (EPCs) under hypoxia. Methods and results Aging reduced the blood flow and vessel density in ischemic muscles in mice. Levels of phosphorylated Src (p-Src), p-β 3 , and p-VEGFR-2 in acute ischemia were reduced in the muscles of aged mice compared to young mice. The hypoxia-inducible factor (HIF)-1α stabilizer deferoxamine improved the age-related impairment of angiogenesis, but this effect was diminished by LY290004, an inhibitor of phosphatidylinositol 3-kinase. Deferoxamine improved the reduction in chronic ischemia-induced β 3 -integrin and VEGFR-2 phosphorylation in the muscles of aged mice; this effect was also diminished by LY290004. In EPCs, we identified the molecular requirements for VEGF-mediated β 3 -integrin and VEGFR-2 cross-activation in vitronectin-induced cell adhesion under acute hypoxia. We demonstrated that c-Src controlled the adhesion- and VEGF-induced β 3 tyrosine phosphorylation in hypoxia. Aging enhanced the hypoxia-induced EPC apoptosis and impaired several c-Src-related VEGF-induced receptor events, including β 3 tyrosine activation, ligand binding, cell adhesion, and tubulogenesis in cultured EPCs of animals and those of humans. Conclusions These data suggest that the aging-related decline in angiogenic action in response to ischemia is mediated by the impairment of cross-activation between β 3 and VEGFR-2 in EPCs, which is partially associated with decreased HIF-1α stability.

OBJECTIVE The accumulation of dry matter, nitrogen, phosphorus and potassium in Prunella vulgaris and their relationships under field condition were studied, in order to provide a basis for the rational fertilization. METHOD Through the dynamic sampling of P. vulgaris in different growing stages, and the dry weight of plant, the amount of dry matter and the content of N, P and K within each organ of the plant were measured. RESULT The dry weight of P. vulgaris linearly increased with the increase of nitrogen, phosphorus and potassium accumulation, there existed a significant correlation at whole growth period. The maximum stage accumulation rate of dry matter from mid-April to the beginning of May, reached 63.71%. The amount of dry matter was mainly distribution in leaves from late March to mid-April. The distribution ratio in stem was the highest from beginning of May to late May. Until mid-June, the distribution ratio of dry matter in spicas was higher than that in other organs. The absorption amounts of N, P and K were lower before mid-April, and the nutrient element was concentrated in plant leaves. From late April to beginning of May, the N, P and K accumulation reached maximum of total absorptive capacity, which accounted for 72.35%, 59.82%, 87.41%, respectively, and the mineral elements were concentrated distribution of plant stems. When transferred to reproductive stage, both accumulation amount and distribution rate of nutrient elements in spicas increased rapidly, which reached the maximum until mid-June. From elongation stages to quaring period was the period of maximal accumulation of dry matter and showed the maximal efficiency of N, P and K nutrition. CONCLUSION The time from elongation stages to quaring period is the most crucial period in the growth development stage of P. vulgaris, and should be paid more attention to the supply of mineral nutrition and moisture of plant to promote spicas formation and dry matter accumulation in this stage. The average N, P2O5 and K2O absorption amount per 100 kg dry matter of spicas were 1.62, 0.36, 2.88 kg respectively, and the ratio of N-P2O5,-K2O was 1 : 0.22: 1.77.

OBJECTIVE To study the effects of nitrogen (N), phosphorus (P2O5), potassium (K2O) and organic compound fertilizer (OF) on spicas biomass and yield of Prunella vulgaris in order to provide a theoretical basis for good agriculture practice (GAP). METHOD Field plot experiments with a 4-variable quadratic orthogonal rotation combination design were adopted, and a function model of spicas yield in P. vulgaris was established. RESULT The model analysis showed that spicas yields of P. vulgaris were significantly influenced under the N, P2O5 and K2O applications, among there factors, N had the greatest effects on spicas yield of P. vulgaris, the next was P2O5 and K2O, OF had the smallest effects on spicas yield. At the lower fertility levels, the spicas yields of P. vulgaris were improved along with the increasing of N, P2O5, K2O and OF applications, but the spicas yields decreased when N, P2O5, K2O and OF were applied too much. CONCLUSION In this experiment condition, the spicas yields of P. vulgaris could reach to 722 kg x hm(-2) when the fertilizer rates were N 303. 9-335.1 kg x hm(-2), P2O5 432.5-500.6 kg x hm(-2), K2O 206.6-240.2 kg x hm(-2), OF 2 312.5-2 687.5 kg x hm(-2).

OBJECTIVE To analyze the dynamic change of chemical constituents in Changium smyrnioides at different ages and give a reference for standard cultivation. METHOD The contents of polysaccharides, mannitol and choline in the roots were determined by colorimetry. HPLC was used to analyze water-soluble components in the roots. GC-MS was used to analyze volatile oil components in the leaves. Similarity coefficient of water-soluble components was calculated by included angle cosine method. RESULT There was significant difference in content of the analyzed chemical constituents except polysaccharide. Contents of mannitol, physiological ash and polysaccharide in the adult plant were higher than those in the young plant. On the contrast, content of water-soluble components and choline in the young plant was higher than that in the adult plant. With the increase of the growth years, water-soluble components in the roots and volatile oil components in the leaves were gradually concentrated. CONCLUSION The growth time significantly affects the chemical constituents in Ch. smyrnioides, the reasonable harvest time is from the second to the forth year after transplanting.