MicroRNA-124-5p delays the progression of cerebral aneurysm by regulating FoxO1.

Cerebral aneurysm (CA) is a common brain disease, and the development of cerebral aneurysm is driven by inflammation and hemodynamic stress. MicroRNA (miR)-124-5p is reported to be associated with inflammatory response in brain disease such as cerebral ischemia-reperfusion injury. However, the function and molecular mechanism of miR-124-5p in CA are not clear, thus, the effects of miR-124-5p on inflammatory response in CA were explored. Firstly, the expression of miR-124-5p in the peripheral blood of patients with CA and the control group was detected by reverse transcription-quantitative PCR. Then, the human umbilical vein endothelial cells (HUVECs) were used as an in vitro model system and stimulated with interleukin (IL)-1ß to simulate the inflammatory environment of CA, and the expression of miR-124-5p was detected. Next, the effect of miR-124-5p on the migration and invasion of HUVECs was detected using Transwell assays. Meanwhile, the function of miR-124-5p on various inflammatory factors was determined by western blotting and enzyme-linked immunosorbent assay (ELISA). Next, the TargetScan website was used to predict FoxO1 as a target gene of miR-124-5p, and this target association was validated by double luciferase reporter assay and western blotting. Finally, the interaction of miR-124-5p with FoxO1 in CA was measured by Transwell western blotting and ELISA assays. The results showed that the expression level of miR-124-5p in the peripheral blood of patients with CA was lower compared with that of control group, and the miR-124-5p in HUVECs stimulated by IL-1ß was less compared with that in normal HUVECs. Besides, miR-124-5p could inhibit the migration and invasion abilities of HUVECs and the release of inflammatory factors. Additionally, the overexpression of miR-124-5p was able to inhibit the expression of FoxO1. miR-124-5p-inhibitor promoted the migration and invasion of HUVECs, as well as inflammatory response, which was weakened following the introduction of FoxO1 small interfering RNA. Overall, the present study demonstrated that miR-124-5p could prevent the occurrence and development of cerebral aneurysm by downregulating the expression of FoxO1.

Promotion of hexadecyltrimethyleamine bromide to the damage of Alexandrium sp. LC3 by cupric glutamate.

The effect of hexadecyltrimethyleamine bromide (HDTMAB) on the removal of Alexandrium sp. LC3 under cupric glutamate stress was investigated. Toxic effect of cupric glutamate on A lexandrium sp. LC3 was significantly promoted in the presence of HDTMAB, especially at 3.0 cmc of HDTMAB. It was found that the sulfhydryl group content of the cell decreased, while the malonaldehyde content and membrane permeability increased when Alexandrium sp. LC3 was treated with HDTMAB and cupric glutamate complex, compared with cupric glutamate alone. The data suggest that HDTMAB might stimulate the damage of Alexandrium sp. LC3 by enhancing the membrane permeability.

Effects of exogenous Ca2+ on the membrane permeability, MDA and SH group content of Alexandrium sp. LC3 under surfactant stress.

The effect of Ca2+ on the removal of Alexandrium sp. LC3 under HDTMAB stress was investigated. The results showed that the toxic effect of HDTMAB on Alexandrium sp. LC3 was significantly reduced in the presence of Ca2 , especially under 4 mmol/L of Ca2+. To understand the underlying mechanism, the SH group and MDA content of the cell membrane and membrane permeability were measured. It was found that the SH content of cell member increased, the MDA content and membrane permeability decreased when Alexandrium sp. was treated with Ca2+ and HDTMAB complex, compared with using HDTMAB only. The data suggested that Ca2+ might promote HDTMAB stress resistance of Alexandrium sp. LC3 by reducing the permeability and increasing the stability of cell membrane.

Effect of Cd on GSH and GSH-related enzymes of Chlamydomonas sp. ICE-L existing in Antarctic ice.

Glutathione (GSH) and GSH-related enzymes play a great role in protecting organisms from oxidative damage. The GSH level and GSH-related enzymes activities were investigated as well as the growth yield and malonyldialdehyde (MDA) content in the Antarctic ice microalga Chlamydomonas sp. ICE-L exposure to the different cadmium concentration in this paper. The results showed that the higher concentration Cd inhibited the growth of ICE-L significantly and Cd would induce formation of MDA. At the same time, it is clear that GSH level, glutathione peroxidases (GPx) activity and glutathione S-transferases (GST), activity were higher in ICE-L exposed to Cd than the control. But GR activity dropped notably when ICE-L were cultured in the medium containing Cd. Increase of GSH level, GPx and GST activities acclimate to oxidative stress induced by Cd and protect Antarctic ice microalga Chlamydomonas sp. ICE-L from toxicity caused by Cd exposure. These parameters may be used to assess the biological impact of Cd in the Antarctic pole region environment.

[Physiological effects of taurine on the growth of wheat (Triticum aestivum L.) seedlings].

Wheat (Triticum aestivum L.) seedlings were grown in taurine solution at concentrations of 10, 100, 500, 1000 and 5000 mg/L, and the photochemistry efficiency, the relative permeability of membrane, membrane lipid peroxidation and the growth indexes in wheat seedlings were determined. The results showed that taurine treatments distinctly promoted the growth of wheat seedlings and increased root length, plant height, dry weight and fresh weight single plant of wheat seedlings. In addition, the photochemistry efficiency in the leaf was also increase, and the membrane relative permeability and the content of membrane lipid peroxidation product MDA were decreased, with an optimum treatment concentration at about 500 mg/L. It suggests that taurine has protective effects on the cell membrane of wheat seedlings to the certain extent.

Purification and characterization of a cold-active iron superoxide dismutase from a Psychrophilic Bacterium, Marinomonas sp. NJ522.

Marinomonas sp. NJ522, isolated from Antarctic sea ice, produces a cold-active iron superoxide dismutase (SOD; EC 1.15.1.1). The purified SOD was dimeric and had an approx. Mr of 48 kDa. Highest activity was detected from pH 8 to 10 and at 40 degrees C (assayed over 10 min). Activity at 0 degree C was nearly 35% of the maximum activity.

Purification and characterization of an extracellular cold-active serine protease from the psychrophilic bacterium Colwellia sp. NJ341.

Colwellia sp. NJ341, isolated from Antarctic sea ice, secreted a cold-active serine protease. The purified protease had an apparent Mr of 60 kDa by SDS-PAGE and MALDI-TOF MS. It was active from pH 5-12 with maximum activity at 35 degrees C (assayed over 10 min). Activity at 0 degrees C was nearly 30% of the maximum activity. It was completely inhibited by phenylmethylsulfonyl fluoride.