Multifactorial nature of hepatocellular carcinoma drug resistance: Could plant polyphenols be helpful?

Primary hepatocellular carcinoma （HCC） is a quite frequent tumor which results in high mortality and most often exhibits a poor response to present drug therapies. Clearly, a thorough understanding of the biological bases of this malignancy might suggest new strategies for its treatment. Here we examine the evidences that both ＂pharmacological＂ mechanisms （e.g. drug transporter or detoxification enzyme over-expression） and alterations in other critical factors, including the IAPs （Inhibitory of Apoptosis Proteins）, involved in enhancement of cell survival and proliferation may determine the therapeutic resistance of HCC; we also underline the possible role in the process of the activation of transcription factors, like NF-κB, capable of contemporaneously up-regulating the mechanisms discussed. On this basis, we finally comment on the possible use of natural multi-targeted antitumoral agents like plant polyphenols to achieve sensitization to treatments in HCC.

Wearable synthetic leather-based high-performance X-ray shielding materials enabled by the plant polyphenol-and hierarchical structure-facilitated dispersion

Effective protection against X-ray is the premise of utilizing the X-ray,thus it is critical to develop novel X-ray shielding materials with both low density and high X-ray attenuation efficiency.As the even distribution of high-Z element components is of great significance for increasing the attenuation efficiency of X-ray shielding materials,in this study,the microfiber membrane(MFM),a type of synthetic leather featuring hierarchical structure was chosen to provide large surface area for the dispersion of rare earth(RE)element.Meanwhile,plant polyphenol was utilized to achieve the stable loading and uniform dispersion of the Ce or Er into MFM.Benefiting from the assistance of polyphenol and hierarchical structure of MFM,the even dispersion of RE element was successfully realized.The resultant shielding materials displayed approximately 10%superior X-ray attenuation efficiency compared to that without polyphenol,and an averagely 9%increment in X-ray attenuation efficiency than that without hierarchical structure.Moreover,the obtained composite with a thickness of 2.8 mm displayed superior X-ray shielding performance compared to 0.25 mm lead sheet in 16-83 keV and retained an ultralow density of 1.4 g cm^(-3).Our research results would shed new light on the manufacture of high-performance X-ray shielding materials with excellent X-ray shielding performance.

Galangin probably ameliorates hyperuricemia by inhibiting urate acid transport 1 (URAT1): Homology modeling and mechanism exploration

Urate acid transporter 1(URAT1)is the main transporter of uric acid reabsorption,which closely related to the pathogenesis of hyperuricemia.Screening URAT1 inhibitors and studying their possible metabolic processes is a hot spot in the development of uric acid-lowering drugs.Studies have shown that many food-borne plant polyphenols have uric acid lowering activity with non-toxic side eff ects,and can be used to improve and alleviate hyperuricemia.In this study,we take galangin(GAL)as an example to explore the mechanism of plant polyphenols aff ecting hyperuricemia by inhibiting URAT1.Homology modeling was used to construct a three-dimensional model of URAT1 protein,and the structure was optimized.Ramachandran diagram was used to verify the rationality of model protein structure.A known URAT1 inhibitor,benzbromarone(BBR),was used to dock with URAT1 to determine the docking site and show the key amino acids.GAL and model protein were docked by molecular docking method to analyze their interaction.Meanwhile,comparing the interaction of BBR and GAL with the key amino acids of model proteins,the binding of GAL was more stable,suggesting that GAL could aff ects hyperuricemia by inhibiting URAT1.This paper aims to provide theoretical guidance for the development of new functional food ingredients for lowering uric acid.

Shifts in community leaf functional traits are related to litter decomposition along a secondary forest succession series in subtropical China

Aims We investigated shifts in community-weighted mean traits(CWm)of 14 leaf functional traits along a secondary successional series in an evergreen broadleaf forest in subtropical southeast China.most of the investigated traits have been reported to affect litter decomposition in previous studies.We asked whether changes in CWms along secondary succession followed similar patterns for all investigated traits and whether the shifts in CWm indicated a change in resource use strategy along the successional gradient.using community decomposition rates(k-rates)estimated from annual lit-ter production and standing litter biomass,we asked whether the dynamics of litter decomposition were related to changes in leaf functional traits along the successional series.Methods twenty-seven plots were examined for shifts in leaf CWm traits as well as in k-rates along a series of secondary forest succession cov-ered in the framework of the bEF-China project.We investigated whether the changes in CWms followed similar patterns for all traits with ongoing succession.three alternative linear models were used to reveal the general patterns of shifts in CWm trait values.moreover,multiple regression analysis was applied to investigate whether there were causal relationships between the changes in leaf functional traits and the dynamics of litter decomposition along secondary succession.We furthermore assessed which traits had the highest impact on community litter decomposition.Important Findingsshifts in CWm values generally followed logarithmic patterns for all investigated traits,whereas community k-rates remained stable along the successional gradient.In summary,the shifts in CWm values indicate a change in community resource use strategy from high nutrient acquisition to nutrient retention with ongoing succession.stands with higher CWm values of traits related to nutrient acquisition had also higher CWm values of traits related to chemical resistance,whereas stands with higher CWm values of traits related to nutrient retention exhibited higher CWm values in leaf physical defense.moreover,high values in CWm values related to nutritional quality(such as high leaf phosphorus concentrations)were found to promote com-munity k-rates,whereas high values in physical or chemical defense traits(such as high contents in polyphenols or high leaf toughness)decreased litter decomposition rates.In consequence,litter decom-position,which was simultaneously affected by these characteristics,did not change significantly along succession.our findings show that leaf decomposition within the investigated communities is dependent on the interplay of several traits and is a result from interactions of traits that affect decomposition in opposing directions.

Facile synthesis of metal-polyphenol-formaldehyde coordination polymer colloidal nanoparticles with sub-50 nm for T_(1)-weighted magnetic resonance imaging

Plant polyphenol-based coordination polymers(CPs) with ultra-small particle size and tailorable compositions are highly desired in biomedical applicatio ns,but their synthesis is still challenging due to the sophisticated coordination assembly process and unavoidable self-oxidation polymerization of polyphenol. He rein,a general ligand covalent-modification mediated coordination assembly strategy is proposed for the synthesis of water-dispersible CPs with tunable metal species(e.g., Gd,Cu,Ni,Zn,Fe)and ultra-small diameter(8.6-37.8 nm) using nontoxic plant polyphenol(e.g..tannic acid,gallic acid) as a polymerizable ligand.Polyphenol molecules react with formaldehyde firstly,which can effectively retard the oxidation induced self-polymerization of polyphenol and lead to the formation of metal ions containing CPs colloidal nanoparticles.These ultrafine nanoparticles with stably chelated metal io ns are highly water dispersible and thus advantageous for bioimaging.As an example,ultra-small Gd contained CPs exhibit higher longitudinal relaxivity(r_(1)=25.5 L mmol^(-1) s^(-1)) value with low r2/r1(1.19) than clinically used Magnevist(Gd-DTPA,r1=3.7 L mmol^(-1) s^(-1)) .Due to the enhanced permeability and retention effect,they can be further used as a positive contrast agent for T1-weighted MR imaging of tumour.