A Primary Study of the Antioxidant, Hypoglycemic, Hypolipidemic, and Antitumor Activities of Ethanol Extract of Brown Slimecap Mushroom, Chroogomphus rutilus (Agaricomycetes).

In vivo and in vitro treatments were carried out to investigate the effects of a 95% ethanol extract of Chroogomphus rutilus (CRE) on antioxidant, hypoglycemic, hypolipidemic, and antitumor properties. CRE showed potent radical scavenging activity against DPPH in vitro. It could increase antioxidant enzymatic activities (superoxide dismutase and glutathione peroxidase) and could reduce malondialdehyde content in vivo in mice in which aging was induced by D-galactose. CRE had hypoglycemic activity and could significantly inhibit α-glucosidase activity in vitro and decrease blood glucose concentration in vivo. CRE could decrease the serum total cholesterol, triglyceride, and low-density lipoprotein cholesterol levels and increase the high-density lipoprotein cholesterol level in diabetic mice. The MTT assay showed that CRE also had a certain inhibitory effect on the tumor cells. These results suggest that CRE may be beneficial for human health and could be useful for applications in medicine, the food industry, and agriculture.

Tetramethylpyrazine induces SH-SY5Y cell differentiation toward the neuronal phenotype through activation of the PI3K/Akt/Sp1/TopoIIß pathway.

Tetramethylpyrazine (TMP) is an active compound extracted from the traditional Chinese medicinal herb Chuanxiong. Previously, we have shown that TMP induces human SH-SY5Y neuroblastoma cell differentiation toward the neuronal phenotype by targeting topoisomeraseIIß (TopoIIß), a protein implicated in neural development. In the present study, we aimed to elucidate whether the transcriptional factors specificity protein 1 (Sp1) and nuclear factor Y (NF-Y), in addition to the upstream signaling pathways ERK1/2 and PI3K/Akt, are involved in modulating TopoIIß expression in the neuronal differentiation process. We demonstrated that SH-SY5Y cells treated with TMP (80µM) terminally differentiated into neurons, characterized by increased neuronal markers, tubulin ßIII and microtubule associated protein 2 (MAP2), and increased neurite outgrowth, with no negative effect on cell survival. TMP also increased the expression of TopoIIß, which was accompanied by increased expression of Sp1 in the differentiated neuron-like cells, whereas NF-Y protein levels remained unchanged following the differentiation progression. We also found that the phosphorylation level of Akt, but not ERK1/2, was significantly increased as a result of TMP stimulation. Furthermore, as established by chromatin immunoprecipitation (ChIP) assay, activation of the PI3K/Akt pathway increased Sp1 binding to the promoter of the TopoIIß gene. Blockage of PI3K/Akt was shown to lead to subsequent inhibition of TopoIIß expression and neuronal differentiation. Collectively, the results indicate that the PI3K/Akt/Sp1/TopoIIß signaling pathway is necessary for TMP-induced neuronal differentiation. Our findings offer mechanistic insights into understanding the upstream regulation of TopoIIß in neuronal differentiation, and suggest potential applications of TMP both in neuroscience research and clinical practice to treat relevant diseases of the nervous system.

Iso-suillin isolated from Suillus luteus, induces G1 phase arrest and apoptosis in human hepatoma SMMC-7721 cells.

Iso-suillin, a natural product isolated from Suillus luteus, has been shown to inhibit the growth of some cancer cell lines. However, the molecular mechanisms of action of this compound are poorly understood. The purpose of this study was to investigate how iso-suillin inhibits proliferation and induces apoptosis in a human hepatoma cell line (SMMC-7721). We demonstrated the effects of iso-suillin on cell proliferation and apoptosis in SMMC-7721 cells, with no apparent toxicity in normal human lymphocytes, using colony formation assays and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) analysis. Western blotting was used to examine the expression of G1 phase-regulated and apoptosis-associated protein levels in iso-suillin treated SMMC-7721 cells. The results indicated that iso-suillin significantly decreased viability, induced G1 phase arrest and triggered apoptosis in SMMC-7721cells. Taken together, these results suggest the potential of iso-suillin as a candidate for liver cancer treatment.

The fungicidal terpenoids and essential oil from Litsea cubeba in Tibet.

A new C9 monoterpenoid acid (litseacubebic acid, 1) and a known monoterpene lactone (6R)-3,7-dimethyl-7-hydroxy-2-octen-6-olide (2), along with three known compounds--vanillic acid (3), trans-3,4,5-trimethoxylcinnamyl alcohol (4), and oxonantenine (5)--were isolated with bioassay-guided purification from the fruit extract of Litsea cubeba collected in Tibet. The structure of 1 was elucidated by MS, ¹H-NMR, ¹³C-NMR, COSY, HSQC, HMBC, NOE spectral data as 2,6-dimethyl-6-hydroxy-2E,4E-hepta-2,4-diene acid. Additionally 33 compounds were identified from the essential oil of L. cubeba. The preliminary bioassay results showed that 1 and 2 have good fungicidal activities against Sclerotinia sclerotiorum, Thanatephorus cucumeris, Pseudocer-cospora musae and Colletotrichum gloeosporioides at the concentration of 588 and 272 µM, and the essential oil has good fungicidal activities against T. cucumeris and S. sclerotiorum, with IC50 values of 115.58 and 151.25 µg/mL, repectively.