[Effect of Biantie pretreatment on serum level of PHD2/HIF-1α and brain tissue damage in rats during acute hypobaric hypoxia exposure].

OBJECTIVE: To observe the effect of Biantie (bian stone plaste) pretreatment on serum level of prolyl hydroxylase domain 2 (PHD2) and hypoxia-inducible factor-1α (HIF-1α) in rats with acute hypobaric hypoxia induced-brain injury, and to explore the possible mechanism of Biantie on preventing brain injury at high altitude. METHODS: Forty-five male SD rats were randomly divided into a blank group, a model group, a Biantie group, a medication group and a Biantie+inhibitor group, 9 rats in each group. The rats in the Biantie group the and the Biantie+inhibitor group were pretreated with Biantie at "Taiyuan" (LU 9), "Neiguan" (PC 6) and "Renying" (ST 9), 2 h each time, once a day; the rats in the medication group were treated with intragastric administration of rhodiola capsule solution (280 mg/kg) for 14 d; the rats in the Biantie+inhibitor group were intraperitoneally injected with the PHD inhibitor dimethyloxalyl glycine (DMOG) at a dose of 40 mg/kg 24 h before the establishment of the model. After the intervention, except for the blank group, the rats in the remaining 4 groups were placed in the oxygen chamber to simulate a high-altitude environment to establish the acute hypobaric hypoxia brain injury model. The arterial blood-gas analysis indexes [blood oxygen saturation (SaO2), lactic acid (Lac), blood sodium (Na+), blood potassium (K+)] and brain water content were detected in each group; the histomorphology of cerebral cortex was observed by HE staining; the serum levels of PHD2 and HIF-1α as well as vascular endothelial growth factor (VEGF) were detected by ELISA; the VEGF protein expression in brain tissue was detected by Western blot; the VEGF mRNA expression in brain tissue was detected by real-time fluorescent quantitative PCR. RESULTS: Compared with the blank group, the levels of SaO2 and Na+ in the model group were decreased (P<0.05), while the levels of Lac and K+ as well as the water content of brain tissue were increased (P<0.05). Compared with the model group, the level of SaO2 in the Biantie group and the medication group was increased (P<0.05), while the levels of Lac, K+ and the water content of brain tissue were decreased (P<0.05); the level of Na+ in the Biantie group was increased (P<0.05). Compared with the Biantie group, the level of SaO2 in the Biantie+inhibitor group was decreased (P<0.05), and the level of Lac and the water content of brain tissue were increased (P<0.05). In the model group, the cortical tissue cells were loose and disordered, the cortical blood vessels were dilated, and the cells were obviously swollen; the anoxic injury in the Biantie group and the medication group was lighter, and the anoxic injury in the Biantie+inhibitor group was more obvious than that in the Biantie group. Compared with the blank group, the serum PHD2 content in the model group was decreased and the HIF-1α content was increased (P<0.05), and the content of VEGF in serum and VEGF protein and mRNA expressions in brain were increased (P<0.05). Compared with the model group, the content of PHD2 in serum in the Biantie group and the medication group was increased (P<0.05), and the level of HIF-1α was decreased (P<0.05), and the content of VEGF in serum as well as VEGF protein and mRNA expressions in brain were decreased (P<0.05). Compared with the Biantie group, the serum PHD2 content in the Biantie+inhibitor group was decreased and HIF-1α level were increased (P<0.05), and the content of VEGF in serum as well as VEGF mRNA expression in brain were increased (P<0.05). CONCLUSION: Biantie at "Taiyuan" (LU 9), "Neiguan" (PC 6) and "Renying" (ST 9) could regulate serum PHD2/HIF-1α to down-regulate VEGF expression, reduce brain edema and enhance anti-hypoxia ability, so as to achieve the purpose of preventing brain injury at high altitude.

Visible light-induced synthesis of 3,4-diarylthiophenes from 3,4-diaryl-2,5-dihydrothiophenes.

Using a catalytic amount of platinum(II) terpyridyl complex 3, 3,4-diarylthiophenes (2a-f) could be synthesized from 3,4-diaryl-2,5-dihydrothiophenes (1a-f) under visible light (λ > 450 nm) irradiation in degassed CH(3)CN. Spectroscopic study and product analysis reveal that the reaction is initiated by photoinduced electron transfer from 3,4-diaryl-2,5-dihydrothiophenes to platinum(II) complex 3, leading to the formation of 3,4-diarylthiophenes.

Silica- and polymer-supported platinum(II) polypyridyl complexes: synthesis and application in photosensitized oxidation of alkenes.

Square-planar polypyridine platinum(II) complexes have been introduced into a silica/polymer matrix by covalent ligand modification. The photophysical properties of the supported matrices are well retained as their model complexes, and the quantum yields for singlet oxygen ((1)O(2)) generation are comparable with that of TPP (tetraphenylporphyrin) under similar conditions. A preliminary application in photosensitized oxidation indicates the silica/polymer-supported matrices are promising, which can be reused without loss of reactivity by a simple filtration. Moreover, the polymer-supported matrix exhibits excellent compatibility in various solvents.

Facile preparation of 3,4-diarylpyrroles and hydrogen by a platinum(II) terpyridyl complex.

With visible-light irradiation of the platinum(II) terpyridyl complex 1 (lambda > 450 nm), an effective photocatalytic conversion from readily available 3,4-diaryl-2,5-dihydropyrroles (2a-2e) to 3,4-diarylpyrroles (3a-3e) and hydrogen (H(2)) is achieved with high efficiency and large catalytic turnover in a homogeneous solution.