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Abstract. The actions of cysteinyl leukotrienes (CysLTs) are mediated by activating CysLT receptors, CysLT 1 , and CysLT 2 . The CysLT 1 receptor mediates vascular responses to CysLTs; however, its effect on the proliferation and migration of endothelial cells is not clarified. To determine this effect, we observed proliferation and migration in EA.hy926 cells, a human endothelial cell line, and the involvement of activation of mitogen-activated protein kinases (MAPKs). We found that LTD 4 did not affect the proliferation, but significantly stimulated the migration of endothelial cells. LTD 4 also induced the phosphorylation of extracellular signalregulated kinase (ERK) 1 / 2, but not those of p38 or JNK. The LTD 4 -induced migration and ERK1/ 2 phosphorylation were blocked by the CysLT 1 -receptor antagonist montelukast and the dual antagonist Bay u9773, but not by the CysLT 2 -receptor antagonist Bay cysLT2; the migration was also inhibited by the ERK1/ 2 inhibitor U0126. Our findings indicate that LTD 4 stimulates the CysLT 1 receptor-mediated migration of endothelial cells; this may be regulated by the ERK1/ 2 pathway.

BackgroundAutophagy induction is a common mechanism for antitumor chemicals in induction of cancer cell death. However, the role of autophagy in crocin-induced apoptosis is barely studied in hepatocellular carcinoma (HCC).Materials and methodsThe influence of crocin on growth, apoptosis, and autophagy and its mutual relations were analyzed by Cell Counting Kit-8 assay, flow cytometer, EGFP-LC3 puncta analysis, and Western blot in HCC cells. The activities of Akt/mTOR axis and its roles in autophagy regulation were also detected by Western blot in HCC cells treated with crocin. Finally, the roles of Akt/mTOR axis in crocin-induced autophagic apoptosis were analyzed by Western blot and flow cytometer in HCC cells.ResultsThe results showed that crocin can induce growth inhibition in a does- and time-dependent pattern by apoptosis. Increased LC3 puncta and upregulated LC3-II accumulation was observed as early as at 6 hours in HepG2 and HCCLM3 cells treated with 3 mg/mL crocin. Moreover, apoptosis analysis using flow cytometer and cleaved poly (ADP-ribose) polymerase detection revealed that autophagy initiation was prior to apoptosis activation in HCC cells treated with crocin. When autophagy was blocked with 3-methyladenine, crocin-induced apoptosis was inhibited in HCC cells. Furthermore, crocin treatment constrained the activities of key proteins in Akt/mTOR signaling, such as p-Akt (S473), p-mTOR (S2448), and p-p70S6K (T389), suggesting that crocin could induce autophagic apoptosis in HCC cells in an Akt/mTOR-dependent mechanism. Indeed, when autophagy was suppressed by forced expression of Akt, the crocin-induced apoptosis was also impaired in HCC cells.ConclusionThe results suggested that crocin could induce autophagic apoptosis in HCC cells by inhibiting Akt/mTOR activity. This study originally revealed that autophagic apoptosis is a novel cytotoxic function of crocin, which lays the theoretical foundation for clinical application of crocin in HCC.

BackgroundSaffron crocus (Crocus sativus) is a valuable spice with medicinal uses in gynaecopathia and nervous system diseases. Identify flowering regulatory genes plays a vital role in increasing flower numbers, thereby resulting in high saffron yield.ResultsTwo full length transcriptome gene sets of flowering and non-flowering saffron crocus were established separately using the single-molecule real-time (SMRT) sequencing method. A total of sixteen SMRT cells generated 22.85 GB data and 75,351 full-length saffron crocus unigenes on the PacBio RS II panel and further obtained 79,028 SSRs, 72,603 lncRNAs and 25,400 alternative splicing (AS) events. Using an Illumina RNA-seq platform, an additional fifteen corms with different flower numbers were sequenced. Many differential expression unigenes (DEGs) were screened separately between flowering and matched non-flowering top buds with cold treatment (1677), flowering top buds of 20 g corms and non-flowering top buds of 6 g corms (1086), and flowering and matched non-flowering lateral buds (267). A total of 62 putative flower-related genes that played important roles in vernalization (VRNs), gibberellins (G3OX, G2OX), photoperiod (PHYB, TEM1, PIF4), autonomous (FCA) and age (SPLs) pathways were identified and a schematic representation of the flowering gene regulatory network in saffron crocus was reported for the first time. After validation by real-time qPCR in 30 samples, two novel genes, PB.20221.2 (p = 0.004, r = 0.52) and PB.38952.1 (p = 0.023, r = 0.41), showed significantly higher expression levels in flowering plants. Tissue distribution showed specifically high expression in flower organs and time course expression analysis suggested that the transcripts increasingly accumulated during the flower development period.ConclusionsFull-length transcriptomes of flowering and non-flowering saffron crocus were obtained using a combined NGS short-read and SMRT long-read sequencing approach. This report is the first to describe the flowering gene regulatory network of saffron crocus and establishes a reference full-length transcriptome for future studies on saffron crocus and other Iridaceae plants.