The role of myocardin-related transcription factor-A in Aß25-35 induced neuron apoptosis and synapse injury.

Myocardin-related transcription factor-A (MRTF-A) highly expressed in brain has been demonstrated to promote neuronal survival via regulating the transcription of related target genes as a powerful co-activator of serum response factor (SRF). However, the role of MRTF-A in Alzheimer's disease (AD) is still unclear. Here, we showed that MRTF-A was significantly downregulated in cortex of the Aß25-35-induced AD rats, which played a key role in Aß25-35 induced cerebral neuronal degeneration in vitro. Bilateral intracerebroventricular injection of Aß25-35 caused significantly MRTF-A expression decline in cortex of rats, along with significant neuron apoptosis and plasticity damage. In vitro, transfection of MRTF-A into primary cultured cortical neurons prevented Aß25-35 induced neuronal apoptosis and synapses injury. And luciferase reporter assay determined that MRTF-A could bind to and enhance the transactivity of the Mcl-1 (Myeloid cell leukemia-1) and Arc (activity-regulated cytoskeletal-associated protein) promoters by activating the key CArG box element. These data demonstrated that the decreasing of endogenous MRTF-A expression might contribute to the development of AD, whereas the upregulation MRTF-A in neurons could effectively reduce Aß25-35 induced synapse injury and cell apoptosis. And the underlying mechanism might be partially due to MRTF-A-mediated the transcription and expression of Mcl-1 and Arc by triggering the CArG box.

Antioxidant and antigenotoxic activity of bioactive extracts from corn tassel.

This study is designed to evaluate antioxidant and antigenotoxic activities of corn tassel extracts (CTTs). The major bioactive components of CTTs include flavonoid, saponin and polysaccharide. The antioxidant properties of the three bioactive components of CTTs were investigated by Ferric Reducing Antioxidant Property (FRAP) and 1, 1-diphenyl-2-picrylhydrazyl (DPPH) assays. The activities of the extracts were determined by assessing the inhibition of mutagenicity of the direct-acting mutagen fenaminosulf, sodium azide, and indirect-acting mutagen 2-aminofluorene using the Ames test (strains TA98 and TA100). The results showed that the extraction rates of flavonoid, saponin, and polysaccharide from the dried corn tassels were 1.67%, 2.41% and 4.76% respectively. DPPH and FRAP assay strongly demonstrated that CTTs had antioxidant properties. CTTs at doses of 625, 1250 and 2500 µg per plate reduced 2-aminofluorene mutagenicity by 12.52%, 28.76% and 36.49% in Salmonella typhimurium TA98 strain assay respectively and by 10.98%, 25.27% and 37.83%, at the same doses in Salmonella typhimurium TA100 assay system, respectively. 3-[4, 5-dimethylthiazol-2-yl]-2, 5-diphenyltetrazolium bromide (MTT) assay showed that the different concentrations of CTTs inhibited the proliferation of MGC80-3 cells in a dose-dependent manner (P<0.01). It is concluded that these integrated approaches to antioxidant and antigenotoxicity assessment may be useful to study corn tassel as a natural herbal material.

Baicalin protects PC-12 cells from oxidative stress induced by hydrogen peroxide via anti-apoptotic effects.

PRIMARY OBJECTIVE: To examine the neuroprotection of baicalin, a flavonoid compound derived from the dried root of Scutellaria baicalensis Georgi, on neurons. RESEARCH DESIGN: A rat PC12 cell line was used to study the neuroprotection and possible mechanisms of baicalin on H2O2-induced neuron damage. METHODS: Three anti- and one pro-apoptosis genes in PC12 cells were examined. Cell apoptosis was induced by H2O2 and apoptotic rate was obtained by flow cytometry. MTT for cell viability, immunofluorescence microscopy for promoter activity and western blot for gene expression were also employed. RESULTS: Data of MTT reduction assay and flow cytometry revealed that viability loss and apoptotic rate were reduced by pre-treatment of PC12 cells with baicalin for 24 hours. Baicalin was also found to increase SOD, GSH-Px activities and to decrease MDA level. Results from Western blot and immunofluorescence microscopy showed baicalin increased the expressions of survivin, Bcl-2 and p-STAT3 and decreased caspase-3 expression which were attenuated by AG-490. CONCLUSIONS: The results point to the possibility of the neuroprotective effects of baicalin on neuronal apoptosis induced by oxidative stress and indicate that activation of the JAK/STAT signalling pathway might involve the anti-apoptotic effect of baicalin.

Antioxidant activity of ginseng cultivated under mountainous forest with different growing years.

Ginseng cultivated and grown naturally under mountainous forest is formally called "Lin-Xia-Shan-Shen" (LXSS) and grown in manual condition is called garden ginseng (GG) according to Chinese pharmacopoeia (2010 edition). Usually the growing condition of LXSS is similar to wild ginseng and mostly used in Chinese folks in ancient times. The antioxidant properties of LXSS with different growing years were evaluated by their inhibitions of thiobarbituric acid-reactive substance (TBA-RS) formation in liver homogenate and 2, 2-diphenyl-1-picrylhydrazyl (DPPH)-radical scavenging activity comparing with those of GG. The inhibitions of different polar extracts (n-butanol and water) of LXSS and GG on TBA-RS formation were also evaluated. The results showed that the antioxidant effects of LXSS were higher than those of GG and the TBARS formation inhibition of LXSS with longer growing years were stronger than those with shorter growing years, while the DPPH-radical scavenging activity of LXSS did not show significant difference with the change of the growing year. The results indicated that the inhibitory effect of TBA-RS formation and the DPPH-radical scavenging of LXSS were correlated with the contents of ginsenosides. In adddition, the starch contents of LXSS and GG were determined by micro-amount method with spectrophotometer. It showed that the starch content in GG was higher than that of LXSS whose starch decreased gradually with the growing year.

catena-Poly[[dichloridocopper(II)]-µ-4,4'-bis-(benzimidazol-1-yl)biphen-yl].

In the title compound, [CuCl(2)(C(26)H(18)N(4))](n), the Cu(II) ion is four-coordinated by two N atoms from two 4,4'-bis-(benzo-imidazol-1-yl)biphenyl ligands and two chloride anions, in a slightly distorted tetra-hedral environment. The biphenyl ligand acts as a linear bidentate ligand, connecting the metal atoms into an infinite chain parallel to [101]. In the biphenyl ligand, the two benzene rings make a dihedral angle of 33.19 (7)°.

Changes of serum omentin-1 levels in normal subjects and in patients with impaired glucose regulation and with newly diagnosed and untreated type 2 diabetes.

AIMS: To assay the levels of serum omentin-1 in subjects with different levels of glucose regulation and to analyze the relationship between serum omentin-1 levels and body mass index (BMI), glycoslated hemoglobin (HbA1c), plasma glucose, insulin resistance index (HOMA-IR), TNF-alpha and IL-6 levels. METHODS: Forty-six patients with impaired glucose regulation (IGR), 55 patients with newly diagnosed and untreated type 2 diabetes mellitus (T2DM), and 50 subjects with normal glucose tolerance (NGT) were enrolled in this study. The levels of serum omentin-1 and plasma glucose at fasting and at 2h after glucose load and fasting serum levels of TNF-alpha, IL-6, insulin, and HbA1c were measured. HOMA-IR was calculated. RESULTS: The levels of serum omentin-1 were lower in the IGR and T2DM groups than in the NGT group. Within groups, omentin-1 levels were no significant difference before and after glucose load. The level of serum omentin-1 was negatively correlated to BMI, HOMA-IR, fasting insulin, TNF-alpha, IL-6, plasma glucose. HOMA-IR and BMI were independent related factors that influenced the levels of serum omentin-1. CONCLUSIONS: Serum omentin-1 levels were decreased in impaired glucose regulation subjects. Lack of omentin-1 may contribute to the development of insulin resistance and T2DM.