scholarly journals A Review of the Receptor-Binding Properties ofp-Synephrine as Related to Its Pharmacological Effects

2011 ◽  
Vol 2011 ◽  
pp. 1-9 ◽  
Author(s):  
Sidney J. Stohs ◽  
Harry G. Preuss ◽  
Mohd Shara
Keyword(s):  
Receptor Binding ◽  
Structural Changes ◽  
Citrus Aurantium ◽  
Pharmacological Effects ◽  
Sports Performance ◽  
Wide Spread ◽  
Binding Properties ◽  
Bitter Orange ◽  
Binding Characteristics ◽  
Amine Neurotransmitters

Bitter orange (Citrus aurantium) extract and its primary protoalkaloidp-synephrine are used widely in weight loss/weight management and sports performance products. Because of structural similarities, the pharmacological effects ofp-synephrine are widely assumed to be similar to those of ephedrine,m-synephrine (phenylephrine), and endogenous amine neurotransmitters as norepinephrine and epinephrine. However, small structural changes result in the receptor binding characteristics of these amines that are markedly different, providing a plausible explanation for the paucity of adverse effects associated with the wide-spread consumption ofp-synephrine in the form of dietary supplements as well as in variousCitrusfoods and juices. This paper summarizes the adrenoreceptor binding characteristics ofp-synephrine relative tom-synephrine, norepinephrine, and other amines as related to the observed pharmacological effects.

scholarly journals Heparin Inhibits Cellular Invasion by SARS-CoV-2: Structural Dependence of the Interaction of the Spike S1 Receptor-Binding Domain with Heparin

2020 ◽  
Vol 120 (12) ◽  
pp. 1700-1715
Author(s):  
Courtney J. Mycroft-West ◽  
Dunhao Su ◽  
Isabel Pagani ◽  
Timothy R. Rudd ◽  
Stefano Elli ◽  
...  
Keyword(s):  
Receptor Binding ◽  
Structural Changes ◽  
Rapid Development ◽  
Antiviral Agents ◽  
Vero Cells ◽  
Binding Domain ◽  
Microbial Pathogens ◽  
Minimum Size ◽  
Structural Basis ◽  
Receptor Binding Domain

AbstractThe dependence of development and homeostasis in animals on the interaction of hundreds of extracellular regulatory proteins with the peri- and extracellular glycosaminoglycan heparan sulfate (HS) is exploited by many microbial pathogens as a means of adherence and invasion. Heparin, a widely used anticoagulant drug, is structurally similar to HS and is a common experimental proxy. Exogenous heparin prevents infection by a range of viruses, including S-associated coronavirus isolate HSR1. Here, we show that heparin inhibits severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) invasion of Vero cells by up to 80% at doses achievable through prophylaxis and, particularly relevant, within the range deliverable by nebulisation. Surface plasmon resonance and circular dichroism spectroscopy demonstrate that heparin and enoxaparin, a low-molecular-weight heparin which is a clinical anticoagulant, bind and induce a conformational change in the spike (S1) protein receptor-binding domain (S1 RBD) of SARS-CoV-2. A library of heparin derivatives and size-defined fragments were used to probe the structural basis of this interaction. Binding to the RBD is more strongly dependent on the presence of 2-O or 6-O sulfate groups than on N-sulfation and a hexasaccharide is the minimum size required for secondary structural changes to be induced in the RBD. It is likely that inhibition of viral infection arises from an overlap between the binding sites of heparin/HS on S1 RBD and that of the angiotensin-converting enzyme 2. The results suggest a route for the rapid development of a first-line therapeutic by repurposing heparin and its derivatives as antiviral agents against SARS-CoV-2 and other members of the Coronaviridae.

scholarly journals Binding Properties of a Dinuclear Zinc(II) Salen-Type Molecular Tweezer with a Flexible Spacer in the Formation of Lewis Acid-Base Adducts with Diamines

Inorganics ◽  
2021 ◽  
Vol 9 (6) ◽  
pp. 49
Author(s):  
Gabriella Munzi ◽  
Giuseppe Consiglio ◽  
Salvatore Failla ◽  
Santo Di Bella
Keyword(s):  
Lewis Acid ◽  
Degrees Of Freedom ◽  
Binding Constants ◽  
Molecular Structures ◽  
Acid Base ◽  
Binding Properties ◽  
Binding Characteristics ◽  
Fluorescence Studies ◽  
Flexible Spacer ◽  
Molecular Tweezer

In this paper we report the binding properties, by combined 1H NMR, optical absorption, and fluorescence studies, of a molecular tweezer composed of two Zn(salen)-type Schiff-base units connected by a flexible spacer, towards a series of ditopic diamines having a strong Lewis basicity, with different chain length and rigidity. Except for the 1,2-diaminoethane, in all other cases the formation of stable 1:1 Lewis acid-base adducts with large binding constants is demonstrated. For α,ω-aliphatic diamines, binding constants progressively increase with the increasing length of the alkyl chain, thanks to the flexible nature of the spacer and the parallel decreased conformational strain upon binding. Stable adducts are also found even for short diamines with rigid molecular structures. Given their preorganized structure, these latter species are not subjected to loss of degrees of freedom. The binding characteristics of the tweezer have been exploited for the colorimetric and fluorometric selective and sensitive detection of piperazine.

scholarly journals Glucocorticoid receptor-binding characteristics in severe asthma

2003 ◽  
Vol 21 (6) ◽  
pp. 985-988 ◽  
Author(s):  
C. Bonnans ◽  
P. Chanez ◽  
H. Meziane ◽  
P. Godard ◽  
J. Bousquet ◽  
...  
Keyword(s):  
Glucocorticoid Receptor ◽  
Severe Asthma ◽  
Receptor Binding ◽  
Binding Characteristics
Sign in / Sign up

Export Citation Format

Share Document