Neuroprotective effect of hyperoside in MPP+/MPTP -induced dopaminergic neurodegeneration.

Parkinson's disease (PD) is a neurodegenerative disease characterized by the pathological loss of nigrostriatal dopaminergic neurons, which causes an insufficient release of dopamine (DA) and then induces motor and nonmotor symptoms. Hyperoside (HYP) is a lignan component with anti-inflammatory, antioxidant, and neuroprotective effects. In this study, 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) and its active neurotoxic metabolite 1-methyl-4-phenylpyridinium ion (MPP+) were used to induce dopaminergic neurodegeneration. The results showed that HYP (100 µg/mL) reduced MPTP-mediated cytotoxicity of SH-SY5Y cells in vitro, and HYP [25 mg/(kg d)] alleviated MPTP-induced motor symptoms in vivo. HYP treatment reduced the contents of nitric oxide (NO), H2O2, and malondialdehyde (MDA), as well as the mitochondrial damage of dopaminergic neurons, both in vitro and in vivo. Meanwhile, HYP treatment elevated the levels of neurotrophic factors such as glial cell line-derived neurotrophic factor, brain-derived neurotrophic factor, and recombinant cerebral dopamine neurotrophic factor in vivo, but not in vitro. Finally, Akt signaling was activated after the administration of HYP in MPP+/MPTP-induced dopaminergic neurodegeneration. However, the blockage of the Akt pathway with Akt inhibitor did not abolish the neuroprotective effect of HYP on DA neurons. These results showed that HYP protected the dopaminergic neurons from the MPP+- and MPTP-induced injuries, which did not rely on the Akt pathway.

Novel naftopidil derivatives containing methyl phenylacetate and their blocking effects on α1D/1A-adrenoreceptor subtypes.

α1-Adrenoceptor (α1-AR) antagonists are considered to be the most effective monotherapy agents for lower urinary tract symptoms associated with benign prostatic hyperplasia (LUTS/BPH). In this study, we synthesized compounds 2-17, which are novel piperazine derivatives that contain methyl phenylacetate. We then evaluated the vasodilatory activities of these compounds. Among them, we found that compounds 2, 7, 12, which contain 2-OCH3, 2-CH3 or 2, 5-CH3, respectively, exhibited potent α1-blocking activity similar to protype drug naftopidil (1). The antagonistic effects of 2, 7, and 12 on the (-)-noradrenaline-induced contractile response of isolated rat prostatic vas deferens (α1A), spleen (α1B) and thoracic aorta (α1D) were further characterized to assess the sub receptor selectivity. Compared with naftopidil (1) and terazosin, compound 12 showed the most desirable α1D/1A subtype selectivity, especially improved α1A subtype selectivity, and the ratios pA2 (α1D)/pA2 (α1B) and pA2 (α1A)/pA2 (α1B) were 17.0- and 19.5-fold, respectively, indicating less cardiovascular side effects when used to treat LUTS/BPH. Finally, we investigated the chiral pharmacology of 12. We found, however, that the activity of enantiomers (R)-12 and (S)-12 are not significantly different from that of rac-12.

X-ray Crystallography, DFT Calculations and Molecular Docking of Indole-Arylpiperazine Derivatives as α1A-Adrenoceptor Antagonists.

Indole-arylpiperazine derivatives have exhibited good selectivity for the α1A-adrenoceptor, but the structure-activity-binding mechanism relationship remains unclear. In the current study, three compounds (1, 2 and 3) were investigated through single-crystal X-ray diffraction analysis, density functional theory (DFT) calculations and molecular docking using a homology model of the α1A receptor. Compounds 1 and 3 form H-bonds networks to stabilize their three-dimensional structures, while C-H···π interactions play a significant role in the packing of 2. Based on DFT-optimized conformations, the HOMO-LUMO energy gaps and molecular electrostatic potential (MEP) were theoretically calculated at the B3LYP/6-311G (d, p) level of theory. Chemical reactivity increases in the order of 3 < 2 < 1, and the maximum positive region of the MEP maps is mainly localized over the NH group. The binding mechanisms of ligand-α1A-adrenoceptor complexes were illustrated by molecular docking. Binding to Gln177 of the second extracellular loop region via hydrogen bonds is likely to be essential for α1A-selective antagonists. The present work sheds light on the studies of structure-activity-binding mechanism and aids in the design of α1A antagonists with high selectivity.

Exogenous interleukin-10 attenuates hyperoxia-induced acute lung injury in mice.

NEW FINDINGS: What is the central question of this study? It is not known whether treatment with interleukin-10 (IL-10) attenuates hyperoxia-induced acute lung injury in mice. What is the main finding and its importance? Our results showed that exogenous IL-10 treatment alleviated hyperoxia-induced acute lung injury in mice, possibly by regulating neutrophil recruitment and the subsequent generation of cytokines, nitric oxide and matrix metalloproteinases. Lung injury caused by breathing air enriched with oxygen continues to be a major problem in clinical medicine. Here, we investigated the therapeutic role of interleukin-10 (IL-10) in hyperoxia-induced acute lung injury in mice. In the first experiment, mice were exposed to room air or 95% O2 and treated with IL-10 simultaneously. In the second experiment, wild-type mice and IL-10(-/-) mice were exposed to room air or 95% O2 . Exogenous IL-10 treatment attenuated hyperoxia-induced acute lung injury, evidenced by a reduced ratio of lung weight to body weight, ratio of lung wet weight to dry weight, cell numbers and protein content in bronchoalveolar lavage fluid and cell death. Interleukin-10 treatment markedly prolonged the survival of mice during oxygen exposure. Interleukin-10 treatment reduced the activity of myeloperoxidase and mRNA levels of interleukin-6, tumour necrosis factor-α and macrophage inflammatory protein 2, suppressed nuclear factor-κB activation and decreased inducible nitric oxide synthnase expression and nitric oxide formation in lungs of mice exposed to hyperoxia. Interleukin-10 treatment suppressed activities of matrix metalloproteinase 2 and matrix metalloproteinase 9 and reduced lung permeability in mice during oxygen exposure. Furthermore, absence of IL-10 aggravated hyperoxia-induced acute lung injury and reduced the duration of survival of mice during oxygen exposure, which was attenuated by treatment with IL-10. In conclusion, our results show that exogenous IL-10 treatment alleviates hyperoxia-induced acute lung injury in mice, possibly by regulating neutrophil recruitment and the subsequent generation of cytokines, nitric oxide and matrix metalloproteinases. This suggests that IL-10 treatment may be a promising therapeutic strategy to reduce lung injury in patients exposed to hyperoxia.