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Fucoxanthin is rich in seaweed and considered as effective anti-cancer drug because of powerful antioxidant properties. The objective of this study was to investigate the role of fucoxanthin on apoptosis, invasion and migration of glioma cells. Firstly, fucoxanthin showed obvious cytotoxicity against human glioma cancer cell line U87 and U251, however, there was no inhibitory effect on normal neuron. And then, fucoxanthin induced apoptotic cell death showed by the condensation of chromatin material stained with Hoechest 33342, and reduced mitochondrial membrane potential via DIOC6(3) staining, and enhanced apoptosis by annexin V-FITC/SYTOX Green double staining on U87 and U251 cell lines. Transmission electron microscopy and western blotting were used to determine ultrastructure of U87 cell and expression of proteins related to apoptosis. A scratch wound healing assay and the expression of matrix metalloproteinases (MMPs), and a tans-well assay were used to investigate cell migration and invasion, respectively. Additionally, we uncovered upstream signaling Akt/mTOR and p38 pathways induced by incubation U87 and U251 cell lines with fucoxanthin that mediated cell apoptosis, migration and invasion by using PI3K and p38 inhibitors. Moreover, incubation of fucoxanthin obviously reduced the weight and volume of glioma mass of U87 cells in nude mice. Furthermore, we also examined the glioma mass of U87 cells by hematoxylin-eosin staining, TUNEL assay and western blot, and these outcomes in vivo consistently confirmed that above results in vitro. Taken together, these findings suggest that fucoxanthin augments apoptosis, and reduces cell proliferation, migration and invasion, and reveals a potential mechanism of fucoxanthin-mediated Akt/mTOR and p38 susspression in human glioblastoma cell line.

Successful embryo implantation requires the establishment of a receptive endometrium. Poor endometrial receptivity has generally been considered as a major cause of infertility. Protein glycosylation is associated with many physiological and pathological processes. The fucosylation is catalyzed by the specific fucosyltransferases. Fucosyltransferase IV (FUT4) is the key enzyme for the biosynthesis of α1,3-fucosylated glycans carried by glycoproteins, and the previous studies showed FUT4 expression changed dynamically during perimplantation. MicroRNAs (miRNAs) are known to regulate specific gene expression. However, the relationship between specific miRNA and FUT4, as well as the role of miRNA/FUT4 in the establishment of uterine receptivity remains elusive. In the current study, we reported that the levels of miR-200 family members were significantly increased in serum from infertility and abortion patients relative to healthy non-pregnancy and early-pregnancy women. Among these, miR-200c was the most sensitive diagnostic criterion for infertility by receiver operating characteristic curve analysis. FUT4 was lower in the serum from infertility and abortion patients compared with the healthy non-pregnancy and early-pregnancy women. Using endometrial cell lines and a mouse model, we demonstrated that miR-200c targeted and inhibited FUT4 expression, leading to the dysfunction of uterine receptivity. Our results also revealed that miR-200c decreased α1.3-fucosylation on glycoprotein CD44, which further inactivated Wnt/β-catenin signaling pathway. Taken together, miR-200c hampers uterine receptivity formation by targeting FUT4 and α1.3-fucosylation on CD44. miR-200c and FUT4 may be applied together as the potential markers for endometrial receptivity, and useful diagnostic and therapeutic targets for infertility.

We previously reported that Astragaloside IV (ASIV), a major active constituent of Astragalus membranaceus (Fisch) Bge protects against cardiac hypertrophy in rats induced by isoproterenol (Iso), however the mechanism underlying the protection remains unknown. Dysfunction of cardiac energy biosynthesis contributes to the hypertrophy and Nuclear Factor κB (NF-κB)/Peroxisome Proliferator-Activated Receptor-γ Coactivator 1α (PGC-1α) signaling gets involved in the dysfunction. The present study was designed to investigate the mechanism by which ASIV improves the cardiac hypertrophy with focuses on the NF-κB/PGC-1α signaling mediated energy biosynthesis. Sprague-Dawley (SD) rats or Neonatal Rat Ventricular Myocytes (NRVMs) were treated with Iso alone or in combination with ASIV. The results showed that combination with ASIV significantly attenuated the pathological changes, reduced the ratios of heart weight/body weight and Left ventricular weight/body weight, improved the cardiac hemodynamics, down-regulated mRNA expression of Atrial Natriuretic Peptide (ANP) and Brain Natriuretic Peptide (BNP), increased the ratio of ATP/AMP, and decreased the content of Free Fat Acid (FFA) in heart tissue of rats compared with Iso alone. In addition, pretreatment with ASIV significantly decreased the surface area and protein content, down-regulated mRNA expression of ANP and BNP, increased the ratio of ATP/AMP, and decreased the content of FFA in NRVMs compared with Iso alone. Furthermore, ASIV increased the protein expression of ATP5D, subunit of ATP synthase and PGC-1α, inhibited translocation of p65, subunit of NF-κB into nuclear fraction in both rats and NRVMs compared with Iso alone. Parthenolide (Par), the specific inhibitor of p65, exerted similar effects as ASIV in NRVMs. Knockdown of p65 with siRNA decreased the surface areas and increased PGC-1α expression of NRVMs compared with Iso alone. The results suggested that ASIV protects against Iso-induced cardiac hypertrophy through regulating NF-κB/PGC-1α signaling mediated energy biosynthesis.

Polycystic ovary syndrome (PCOS) is a complicated reproductive endocrine disease characterized by polycystic ovaries, hyperandrogenism and anovulation. It is one of the main causes of infertility. RU486 is an antagonist of progesterone receptor, and most commonly used as a contraceptive. However, whether RU486 is correlated with PCOS remains unclear. Atrial natriuretic peptide (ANP) is a small peptide with natriuretic and diuretic functions, and its availability to be used in PCOS treatment is unknown. Here, we showed that the serum ANP level was lower in PCOS patients than that in healthy women, and it was also decreased in the serum and ovarian tissues of RU486-induced PCOS rats compared with the control rats. We also found that RU486 inhibited the proliferation and promoted the apoptosis of human KGN ovarian granulosa cells by downregulating progesterone receptor membrane component 1 (PGRMC1). Meantime, ANP promoted the proliferation and inhibited the apoptosis of KGN cells through upregulating ANP receptor A (NPRA). The promotive effects of ANP on ovarian functions were mediated through the formation of an NPRA/PGRMC1/EGFR complex, which further activated MAPK/ERK signaling and transcription factor AP1. Moreover, ANP treatment reversed the PCOS symptoms, and improved the fertility of RU486-induced PCOS rats. Collectively, these findings highlight that RU486 is associated with the pathogenesis of PCOS, and ANP treatment may be a promising therapeutic option for PCOS.

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Aberrant protein fucosylation is associated with cancer malignancy. Fucosyltransferase IV (FUT4) is the key enzyme catalyzing the biosynthesis of α1,3-linkage fucosylated glycans carried by glycoproteins on the cell surface, such as the tumor-associated sugar antigen Lewis Y (LeY). An abnormal increase in the levels of FUT4 and LeY is observed in many cancers and correlated with cell proliferation and metastasis. Some microRNAs (miRNAs) are known to negatively regulate gene expression. FUT4 is an oncogenic glycogene, and thus it is important to identify the specific miRNA targeting FUT4. In current study, we first identified miR-200b as a specific miRNA that inhibited FUT4 expression. We found that miR-200b level was decreased, whereas that of FUT4 was increased in tissues and serum of breast cancer compared with that in the control by real-time PCR, western blotting and enzyme-linked immunosorbent assay. The alterations of miR-200b and FUT4 level were recovered after chemotherapy. The results also showed that miR-200b suppressed FUT4 expression and inhibited tumor growth and metastasis in MCF-7 and MDA-MB-231 breast cancer cells, as well as in the xenografted tumor tissues and metastatic lung tissues. miR-200b decreased the α1,3-fucosylation and LeY biosynthesis on epidermal growth factor receptor (EGFR), as well as inactivation of EGFR and downstream phosphoinositide-3 kinase/Akt signaling pathway. In conclusion, the study highlights that FUT4 could apply as a novel target for miR-200b that suppress the proliferation and metastasis of breast cancer cells by reducing α1,3-fucosylation and LeY biosynthesis of glycoproteins. miR-200b and FUT4 are potential diagnostic and therapeutic targets for breast cancer.

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