Structure-based methoxyflavone derivatives with potent inhibitory activity against various influenza neuraminidases

Communicated by Ramaswamy H. Sarma     

Synthesis,DNA/BSA binding studies and in vitro biological assay of nickel(II) complexes incorporating tridentate aroylhydrazone and triphenylphosphine ligands

Abstract

Two new nickel (II) triphenylphosphine complexes derived from tridentate aroylhydrazone ligands [H₂L¹ = 2-hydroxy-3-methoxybenzylidene)benzohydrazone and H₂L² = N′-(2-hydroxy-3-methoxybenzylidene)-2-hydroxybenzoylhydrazone] and triphenylphosphine were prepared and their molecular structures were determined by single crystal X-ray diffraction analysis. Both nickel(II) complexes showed slightly distorted square planar geometry with one tridentate aroylhydrazone ligand coordinated through ONO donor atoms and one triphenylphosphine ligand coordinated to the nickel center through the phosphorus atom. DNA interaction studies indicated that both complexes possessed higher affinity to herring sperm DNA (HS-DNA) than the corresponding free aroylhydrazone ligand. Molecular docking investigations showed that both complexes could bind to DNA through intercalation of the phenyl rings between adjacent base pairs in the double helix. Meanwhile, bovine serum albumin (BSA) binding studies revealed the complexes could effectively interact with BSA and change the secondary structure of BSA. Further pharmacological evaluations of the synthesized complexes by in vitro antioxidant assays demonstrated high antioxidant activity against NO· and O₂˙^? radicals. The anticancer activity of each complex was assessed through in vitro cytotoxicity assays (CCK-8 kit) toward A549 and MCF-7 cancer cell and normal L-02 cell lines. Significantly, the Ni(II) complex derived from H₂L¹ ligand was found to be more effective cytotoxic toward MCF-7cancerous cell with the IC₅₀ value equaled 9.7?μM, which showed potent cytotoxic activity over standard drug cisplatin.

Abbreviations A549 human lung carcinoma cell

BSA bovine serum albumin

CCK-8 Cell Counting Kit-8

DFT density functional theory

DNA deoxyribonucleic acid

DPPH˙ 2,2-diphenyl-1-picrylhydrazyl

H₂L¹ 2-hydroxy-3-methoxybenzylidene)benzohydrazone N′-(2-hydroxy-3-methoxybenzylidene)-2-hydroxybenzoylhydrazone

H₂L² N′-(2-hydroxy-3-methoxybenzylidene)-2-hydroxybenzoylhydrazone

HOMO highest occupied molecular orbital

IC₅₀ the 50% activity

L-02 human normal liver cell

LOMO lowest unoccupied molecular orbital (LUMO)

MCF-7 human breast carcinoma cell

NO˙ nitric oxide

O₂˙^? superoxide anion

SOD superoxide dismutase

Communicated by Ramaswamy H. Sarma     

Identification and evaluation of reference genes for quantitative real-time PCR analysis in Passiflora edulis under stem rot condition

Molecular Biology Reports - Passion fruit (Passiflora edulis), an important tropical and subtropical fruit, has a high edible and medicinal value. Stem rot disease is one of the most important...     

Peripheral blood mononuclear cell microRNA profiles in syphilitic patients with serofast status

Molecular Biology Reports - Syphilis is a chronic sexually transmitted disease caused by infection with Treponema pallidum, which can invade various system organs, leading to clinical...     

Dexmedetomidine alleviates H2O2-induced oxidative stress and cell necroptosis through activating of α2-adrenoceptor in H9C2 cells

Molecular Biology Reports - Oxidative stress induced necroptosis is important in myocardial ischemia/reperfusion injury. Dexmedetomidine (Dex), an α2-adrenoceptor (α2-AR) agonist, has...     

Polymorphisms of LAP3 gene and their association with the growth traits in the razor clam Sinonovacula constricta

Molecular Biology Reports - Leucine aminopeptidase 3 (LAP3) is an important proteolytic enzyme that catalyzes the hydrolysis of leucine residues from the amino termini of protein or peptide...     

Histopathology,Molecular Identification and Antifungal Susceptibility Testing of Nannizziopsis arthrosporioides from a Captive Cuban Rock Iguana (Cyclura nubila)

Mycopathologia - Chrysosporium-related fungi, the cause of superficial and deep mycoses, are an emerging infectious disease affecting not only reptiles but also immunocompromized humans. However,...     

Noise does not equal bias in assessing the evolutionary history of the angiosperm flora of China: A response to Qian (2019)

In response to our paper on the evolutionary history of the Chinese flora, Qian suggests that certain features of the divergence time estimation employed might have led to biased conclusions in Lu et al (2018). Here, we consider Qian's specific criticisms, explore the extent of uncertainty in the data and demonstrate that (i) no systematic bias toward dates that are too young or too old is detected in Lu et al.; (ii) constraint of the crown age of angiosperms does not bias the generic ages estimated by Lu et al.; and (iii) ages derived from the Chinese regional phylogeny do not bias the conclusions reported by Lu et al. All these analyses confirm that the conclusions reported previously are robust. We argue that, like many large-scale biodiversity analyses, sources of noise in divergence time estimation are to be expected, but these should not be confused with bias.     

Outlier detection methods are still effective even using virtual species created with the probabilistic approach

Liu et al. (Journal of Biogeography, 2018, 45 :164–176) presented an approach to detect outliers in species distribution data by developing virtual species created using the threshold approach. Meynard et al. (Journal of biogeography, 2019, 46 :2141–2144) raised concerns about this approach stating that ‘using a probabilistic approach … may significantly change results’. Here we provide a new series of simulations using the two approaches and demonstrate that the outlier detection approach based on pseudo species distribution models was still effective when using the probabilistic approach, although the detection rate was lower than when using the threshold approach.     

Mulberry Fruit Extract Alleviates Cognitive Impairment by Promoting the Clearance of Amyloid-β and Inhibiting Neuroinflammation in Alzheimer’s Disease Mice

Neurochemical Research - Alzheimer’s disease (AD) is a common neurodegenerative disease, always clinically manifesting with memory loss and other cognitive abilities serious enough to...