scholarly journals Pb2+, Cu2+, Zn2+, Mg2+ and Mn2+ reduce the affinities of flavone, genistein and kaempferol for human serum albumin in vitro

2011 ◽  
Vol 63 (3) ◽  
pp. 623-634 ◽  
Author(s):  
Fan Yang ◽  
Jie Wang ◽  
Chunxi Liu ◽  
Xu Xiaochen ◽  
Li Wenjun ◽  
...  

Flavone (Fl), genistein (Gen) and kaempferol (Kol) were studied for their affinities towards human serum albumin (HSA) in the presence and absence of Pb2+,Cu2+,Zn2+,Mg2+ and Mn2+. The fluorescence intensities of HSA decreased with increasing concentration of the three flavonoids. Kaempferol resulted in a blue-shift of the ?em of HSA from 336 to 330 nm; flavone showed an obvious red-shift of the ?em of HSA from 336 to 342 nm; genistein did not cause an obvious blue-shift or red-shift of the ?em of HSA. However, the extents of ?em-shifts induced by the flavonoids in the presence of metal ions were much bigger than that in the absence of mental ions. Pb2+,Cu2+,Zn2+,Mg2+ and Mn2+ reduced the quenching constants of the flavonoids for HSA by 14.6% to 60.7% , 28% to 67.9%,3.5% to 59.4%, 23.2% to 63.7% and 14% to 65%, respectively. The affinities of flavone, genistein and kaempferol for HSA decreased about 10.84%, 10.05%and 3.56% in the presence of Pb2+, respectively. Cu2+ decreased the affinities of flavone, genistein and kaempferol for HSA about 14.04%, 5.14%and 8.89%, respectively. Zn2+ decreased the affinities of flavone, genistein and kaempferol for HSA about 3.79%, 0.55% and 3.58%, respectively. Mg2+ decreased the affinities of flavone, genistein and kaempferol for HSA about 16.94%, 2.94%and 7.04%, respectively. Mn2+ decreased the affinities of flavone, genistein and kaempferol for HSA about 14.24%, 3.66% and 4.78%, respectively.

2012 ◽  
Vol 41 (6) ◽  
pp. 976-993 ◽  
Author(s):  
Fan Yang ◽  
Jie Wang ◽  
Chunxi Liu ◽  
Xiaochen Xu ◽  
Shunan Shan ◽  
...  

2021 ◽  
pp. 116888
Author(s):  
Fahad A. Alhumaydhi ◽  
Mohammad Abdullah Aljasir ◽  
Abdullah S.M. Aljohani ◽  
Suliman A. Alsagaby ◽  
Ameen S.S. Alwashmi ◽  
...  

2020 ◽  
Vol 14 (1) ◽  
pp. 22
Author(s):  
Kenji Tsukigawa ◽  
Shuhei Imoto ◽  
Keishi Yamasaki ◽  
Koji Nishi ◽  
Toshihiko Tsutsumi ◽  
...  

In a previous study, we reported on the development of a synthetic polymer conjugate of pirarubicin (THP) that was formed via an acid-labile hydrazone bond between the polymer and the THP. However, the synthetic polymer itself was non-biodegradable, which could lead to unexpected adverse effects. Human serum albumin (HSA), which has a high biocompatibility and good biodegradability, is also a potent carrier for delivering antitumor drugs. The objective of this study was to develop pH-sensitive HSA conjugates of THP (HSA-THP), and investigate the release of THP and the cytotoxicity under acidic conditions in vitro for further clinical development. HSA-THP was synthesized by conjugating maleimide hydrazone derivatives of THP with poly-thiolated HSA using 2-iminothiolane, via a thiol-maleimide coupling reaction. We synthesized two types of HSA-THP that contained different amounts of THP (HSA-THP2 and HSA-THP4). Free THP was released from both of the HSA conjugates more rapidly at an acidic pH, and the rates of release for HSA-THP2 and HSA-THP4 were similar. Moreover, both HSA-THPs exhibited a higher cytotoxicity at acidic pH than at neutral pH, which is consistent with the effective liberation of free THP under acidic conditions. These findings suggest that these types of HSA-THPs are promising candidates for further development.


1997 ◽  
Vol 13 (8) ◽  
pp. 677-683 ◽  
Author(s):  
P.J. SWART ◽  
C.S. SUN ◽  
M.E. KUIPERS ◽  
C. ASUNCION ◽  
S. JOSEPHS ◽  
...  

1985 ◽  
Vol 226 (1) ◽  
pp. 251-258 ◽  
Author(s):  
S Itoh ◽  
S Onishi

The present study was performed to elucidate why the photochemical reaction of (ZZ)-bilirubin bound to human serum albumin is singularly selective, and only one of the two (EZ)- and (ZE)-bilirubins, the (ZE)-isomer, is produced. In a kinetic study of the photochemical reaction in vitro, the sum of the relative rate constants of photochemical transformation of (EZ)-bilirubin into both (EZ)-cyclobilirubin and (ZZ)-bilirubin, with a significant preference for the former, was proved to be considerably larger than that of the transformation of (ZZ)-bilirubin into (EZ)-bilirubin. Therefore only one of the geometrical isomers, namely (ZE)-bilirubin, is apparently formed. It was concluded that (EZ)-bilirubin photochemically undergoes (EZ)-cyclization, i.e. structural photoisomerization, while bound to its high-affinity site on human serum albumin, and is an intermediate in the transformation of (ZZ)-bilirubin into (EZ)-cyclobilirubin.


2014 ◽  
Vol 41 (4) ◽  
pp. 2377-2387 ◽  
Author(s):  
Manjunath D. Meti ◽  
Kirthi S. Byadagi ◽  
Sharanappa T. Nandibewoor ◽  
Shrinivas D. Joshi ◽  
Uttam A. More ◽  
...  

2015 ◽  
Vol 68 (12) ◽  
pp. 1894 ◽  
Author(s):  
Mohsen Oftadeh ◽  
Golamreza Rezaei Behbahani ◽  
Ali Akbar Saboury ◽  
Shahnaz Rafiei

The binding parameters between cyclodextrins (CDs) and human serum albumin (HSA) were investigated by isothermal titration calorimetry (ITC), fluorescence quenching, and UV-vis absorption spectroscopy at 300 K in 50 mM phosphate buffer solution. Among the various CDs investigated, β-CD has the greater ability to decrease the aggregation of HSA and the results indicated that the inhibition order is γ-CD < α-CD < β-CD. The obtained heats for HSA+CDs interactions were reported and analysed in terms of the extended solvation model, which was used to reproduce the enthalpies of HSA interactions with CDs over a broad range of complex concentrations. The binding constant and thermodynamic parameters were obtained. These suggested that the binding reaction was driven by both enthalpy and entropy, and electrostatic interactions played a major role in the stabilising of HSA. The parameters and reflected the net effect of β-CD on the HSA stability at low and high cyclodextrin concentrations, respectively. The positive values for indicated that β-CD stabilises the HSA structure at low concentrations. The UV absorption intensity of theses complexes increased and a slight red shift was observed in the absorbance wavelength with increasing the CD concentration. The fluorescence intensity of HSA decreased regularly and a slight blue shift was observed for the emission wavelength with increasing CD concentration. The results indicate that the CD complex could quench the fluorescence of HSA and changes the microenvironment of the tryptophan residue.


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