Garcinia Biflavonoid 1 Improves Lipid Metabolism in HepG2 Cells via Regulating PPARα.

Garcinia biflavonoid 1 (GB1) is one of the active chemical components of Garcinia kola and is reported to be capable of reducing the intracellular lipid deposition, which is the most significant characteristic of non-alcoholic fatty liver disease. However, its bioactive mechanism remains elusive. In the current study, the lipid deposition was induced in HepG2 cells by exposure to oleic acid and palmitic acid (OA&PA), then the effect of GB1 on lipid metabolism and oxidative stress and the role of regulating PPARα in these cells was investigated. We found that GB1 could ameliorate the lipid deposition by reducing triglycerides (TGs) and upregulate the expression of PPARα and SIRT6, suppressing the cell apoptosis by reducing the oxidative stress and the inflammatory factors of ROS, IL10, and TNFα. The mechanism study showed that GB1 had bioactivity in a PPARα-dependent manner based on its failing to improve the lipid deposition and oxidative stress in PPARα-deficient cells. The result revealed that GB1 had significant bioactivity on improving the lipid metabolism, and its potential primary action mechanism suggested that GB1 could be a potential candidate for management of non-alcoholic fatty liver disease.

[Synthesis and DNA-binding properties of three compounds containing pyridinecarboxamide].

N, N'-bis(2-pyridinecarboxamide)-1,2-ethane(H2L1), N, N'-bis(2-pyridinecarboxamide)-1, 2-beneze(H2L2) and N-phenylpyridine-2-carboxamide(HL3) were synthesized, and characterized by elemental analysis, IR and HNMR spectra. UV-visible (UV-Vis) spectra, fluorescence spectra and SERS spectra to study the interaction of the three ligands with calf thymus DNA. UV-visible (UV-Vis) spectra show that with the incremental addition of DNA, the bands of H2L1, H2L2 and HL3 all show Hypochromism. Meanwhile fluorescence spectra show that the addition of the three ligands to DNA pretreated with EB causes an appreciable reduction in fluorescence intensity, indicating that the ligands compete with ethidium bromide in binding to DNA, and free ethidium bromide increases. The addition of DNA causes the SERS signals of the ligands to weakened and some bands to disappeared. Based on the above experimental results, we conclude that the three ligands bind to DNA mainly through the intercalation mode. The binding constant of the three compouds Kb was calculated, 1.20 x 10(4) for H2L1, 1.33 x 10(4) for H2L2 and is 1.52 x 10(4) for HL3. Kr was also calculated to be 0.67, 1.52 and 1.73 for H2L1, H2L2 and HL3, respectively. The value indicates that the binding of HL3 to DNA is stronger than that of H2L1 and H2L2, as HI3 has proper planar structure, smaller molecular volume and less steric hindrance. The three ligands can all induce the cleavage of plasmid pBR322 DNA. An increase in H2L1, H2L2 and HL3 concentrations causes more transformation of plasmid DNA from closed circular conformations to nicked conformations. But linear conformations have not been observed. The cleavage of plasmid pBR322 DNA caused by the three ligands is not selective.

Synthesis, characterization and DNA-binding studies on La(III) and Ce(III) complexes containing ligand of N-phenyl-2-pyridinecarboxamide.

La(III) and Ce(III) complexes containing ligand of N-phenyl-2-pyridinecarboxamide (HL) were synthesized and characterized by elemental analyses, conductivity measurement, IR spectra and thermal analysis. The general formulas of the complexes were [Ln(HL)(3)(H(2)O)(2)](NO(3))(3).2H(2)O [Ln=La(III), Ce(III)]. The results indicated that the oxygen of carbonyl and the nitrogen of pyridyl coordinated to Ln(III), and there were also two water molecules taking part in coordination. Ln(III) and HL formed 1:3 chelate complexes and the coordination number was eight. The interaction between the complexes and DNA was studied by means of UV-vis spectra, fluorescence spectra, SERS spectra and agarose gel electrophoresis. The results showed that complexes can bind to DNA. The binding ability decreased in following order: La(III) complex, Ce(III) complex, and HL. The interaction modes between DNA and the three compounds were found to be mainly intercalative.