ABSTRACT
The catalytic generation of H2 in living cells provides a method for antioxidant therapy.In this study,an[FeFe]-hydrogenase mimic[Ru+Fe2S2@F127(80)]was synthesized by self-assembling polymeric plur-onic F-127,catalytic[Fe2S2]sites,and photosensitizer Ru(bpy)32+.Under blue light irradiation,hydrated protons were photochemically reduced to H2,which increased the local pH in living cells(HeLa cells).The generated H2 was subsequently used as an antioxidant to decrease reactive oxygen species(ROS)levels in living cells(HEK 293T,HepG2,MCF-7,and HeLa cells).Our findings revealed that the proliferation of HEK 293T cells increased by a factor of about six times,relative to that of other cells(HepG2,MCF-7,and HeLa cells).Intracellular ROS and pH levels were then monitored using fluorescent cell imaging.Our study showed that cell imaging can be used to evaluate the ability of Ru+Fe2S2@F127 to eliminate oxidative stress and prevent ROS-related diseases.
ABSTRACT
Aim To study the role of Cx43 hemichannel in rats with acute incision pain. Methods Adult male rats were randomly divided into normal saline group(C group), incision pain group(I group), Gap19 group. Western blot was used to determine the expression of Cx43 and GFAP at 6 h, 3 d and 7 d after paw incision surgery of rats. The rats were intrathecal injected with Gap19 30 min before incision surgery, followed by the measurement of the paw withdrawal threshold to mechanical stimuli at several time points. Immunofluorescence was used to detect the expression of Cx43 and GFAP. ELISA was performed to detect the different inflammatory cytokine levels in rats after surgery. Results Compared with group C, the expression of Cx43 and GFAP of rats increased significantly 6 h after incision surgery in group I, while their expression at postoperative 3 d and 7 d showed no obvious alteration. Compared with the preoperative baseline, the mechanical paw withdrawal threshold in I group and Gap19 group rats was significantly reduced at 2 h, 6 h, 24 h and 3 d post-incision(P<0.01), but it had no obvious change on postoperative 7 d. Compared with group I, the mechanical paw withdrawal threshold in rats of Gap19 group increased 2 h, 6 h, 24 h post-incision, while it showed no statistical difference on 3 d and 7 d post-incision. Compared with group C, immunofluorescence results showed that the expression of GFAP and Cx43 in spinal cord dorsal horn astrocytes also increased significantly in Group I 6 h after incision surgery. Compared with group I, GFAP and the expression of Cx43 were markedly reduced in Gap19 group. There was no statistical difference on 7 d post-incision. Compared with those in group C, the inflammation factors including IL-1β, IL-6 and TNF-αobviously increased in group I. However, in contrary to the rats in group I, the rats pretreated with gap19 showed increased expression of Cx43 and GFAP in spinal cord dorsal horn. Conclusions Specific inhibition of Cx43 hemichannel significantly suppresses astrocyte activation and alters the inflammatory microenvironment in the spinal cord dorsal horn and reduces postoperative hyperalgesia in rats with acute incision pain.
ABSTRACT
In order to establish a method for the determination of the sterols of the oil in the freeze-dried acai (Euterpe oleracea Mart.) and to evaluate its antioxidant activities, a saponification/extraction procedure and high performance liquid chromatography (HPLC) analysis method were developed and validated for the analysis of phytosterols in PEE (Petroleum ether extract). Separation was achieved on a Purosper STAR LP C18 column with a binary, gradient solvent system of acetonitrile and isopropanol. Evaporative light scattering detection (ELSD) was used to quantify β-sitosterol and the total sterols. Peak identification was verified by retention times and spikes with external standards. Standard curves were constructed (r = 0.999 2) to allow for sample quantification. Recovery of the saponification and extraction was demonstrated via analysis of spiked samples. The highest content of total sterols is β-sitosterol. The antioxidant activities of the extracts were evaluated using the total oxyradical scavenging capacity assay (TOSC assay). The result showed that the PEE exhibited significant antioxidant properties, sample concentration and the antioxidant capacity had a certain relevance.