Investigating the specificity of endothelin-traps as a potential therapeutic tool for endothelin-1 related disorders

BACKGROUND

Endothelin (ET)-traps are Fc-fusion proteins with a design based on the physiological receptors of ET-1. Previous work has shown that use of the selected ET-traps potently and significantly reduces different markers of diabetes pathology back to normal, non-disease levels.

AIM

To demonstrate the selected ET-traps potently and significantly bind to ET-1.

METHODS

We performed phage display experiments to test different constructs of ET-traps, and conducted bio-layer interferometry binding assays to verify that the selected ET-traps bind specifically to ET-1 and display binding affinity in the double-digit picomolar range (an average of 73.8 rM, n = 6).

RESULTS

These experiments have confirmed our choice of the final ET-traps and provided proof-of-concept for the potential use of constructs as effective biologics for diseases associated with pathologically elevated ET-1.

CONCLUSION

There is increased need for such therapeutics as they could help save millions of lives around the world.

Endothelin-1 traps as a potential therapeutic tool: from diabetes to beyond?

There is substantial research on the vasoactive peptide endothelin (ET)-1 in physiology, as well as in pathology. In fact, pathologically elevated levels of ET-1 have been found in several disease states, such as various cardiovascular diseases, different cancers, some neurodegenerative disorders, as well as in diabetes. Here, we describe and discuss ET-1, its importance in different diseases, and the potential therapeutic effects of ET-traps in the treatment of these diseases. Previous in vitro and in vivo research (in the diabetes disease space) demonstrated that ET-traps potently and significantly prevent the induction of different markers of diabetes-related pathology. This included induction of extracellular matrix (ECM) proteins (collagen 4α1 and fibronectin), which are pathologically elevated in diabetes. The ET-traps prevented induction of these and brought a significant return to non-diabetic levels. We also discuss the merits of using ET-traps over the currently used endothelin receptor antagonists (ERAs) and previously used therapeutic antibodies.

In vivo studies demonstrate that endothelin-1 traps are a potential therapy for type I diabetes

Background

Type 1 diabetes is a serious, lifelong condition where the body's blood glucose level increases because of the body's inability to make insulin. An important consequence of this is the increased expression of extracellular matrix proteins, such as fibronectin and collagen 4α1, in key tissues and organs like the heart and kidneys. Diabetes is also associated with increased plasma levels of the vasoactive peptide endothelin (ET)-1. This further aggravates the expression of the ECM proteins. There are also important consequences of increased glucose and ET-1 levels in diabetes on the heart, termed diabetic cardiomyopathy.

Methods

We have previously reported the development of ET-traps, which potently and significantly reduce pathological levels of ET-1. In this study, we tested the in vivo therapeutic potential of ET-traps for type 1 diabetes using the B6 mouse model.

Results

Following subcutaneous administration of ET-traps 3 times a week, over a 2 month period, the 500 nM dose of ET-traps gave a significant reduction in collagen 4α1 expression in the heart and kidney, returning it back to control, non-diabetic levels at both the mRNA and protein levels. The expression of fibronectin mRNA is also returned to control levels with the 500 nM dose of ET-traps. The efficacy of ET-traps for type 1 diabetes was further evinced by immunohistochemistry data, echocardiography studies (measuring left ventricular systolic function and diastolic dysfunction) and a measure of urine creatinine and albumin levels. In all analyses, the 500 nM dose of ET-traps returns the different measures to control, non-diabetic levels.

Conclusion

Data from this study show that in a mouse model ET-traps have a potent and significant therapeutic effect on diabetes disease pathology. Future studies could further evaluate the use of ET-traps as a therapy for diabetes, including taking them through clinical trials.

Intercalated Two-Dimensional Ceramic Nanocomposites

New generations of polymer-ceramic nanocomposites are being developed by intercalation of layered solids. Synthetic approaches include intercalative polymerization, direct polymer intercalation and molecular dispersion of the host layers in the polymer matrix. The unique physical and mechanical properties of the hybrids are attributed to the molecular dispersion and the synergism between the individual components.

Intercalation Chemistry: a Novel Approach To Materials Design

Intercalation of layered solids is used as a means to manipulate a variety of molecular and polymeric species into well-ordered multilayer films with an architecture controllable at the molecular level. Dielectric, conductivity and optical measurements demonstrate the potential of developing new families of materials with new functionalities by exploiting the synergistic effect of guest/host interactions.

Intercalated Two-Dimensional Ceramic Nanocomposites

New generations of polymer-ceramic nanocomposites are being developed by intercalation of layered solids. Synthetic approaches include intercalative polymerization, direct polymer intercalation and molecular dispersion of the host layers in the polymer matrix. The unique physical and mechanical properties of the hybrids are attributed to the molecular dispersion and the synergism between the individual components.

Conducting Molecular Multilayers: Intercalation of Conjugated Polymers in Layered Media

Polyaniline has been synthesized in the galleries of fluorohectorite, a two-dimensional mica-type layered silicate. Intercalation of aniline in the intracrystalline region of Cu-exchanged fluorohectorite results in oxidative polymerization to polyaniline (emeraldine base form) as demonstrated by electronic, infrared and Raman spectroscopy and x-ray diffraction data. The intercalated insulating form of polyaniline becomes conducting on exposure to HCl. In-plane electrical conductivity data measured in the temperature range 274 to 573 K show a complex thermally activated behavior with room temperature conductivity 0.05 Ohm−1cm−1. The polyaniline/layered silicate hybrids represent a new class of nanocomposites consisting of synthetic conductors with molecular dimensions contained in a quasi twodimensional environment of a crystalline host.

Tobacco control legislation in India: past and present

Beginning with the Cigarettes Act, 1975, a number of legislative strategies and programs to curb tobacco use have been implemented in India, with limited success. Currently, the Cigarettes and Other Tobacco Products Act, 2003, is designed to curb the use of tobacco in order to protect and promote public health. This review presents a critical appraisal of the current situation in its historical context.

Matrix-Mediated Synthesis of Nanocrystalline ggr-Fe2O3: A New Optically Transparent Magnetic Material

A new magnetic material with appreciable optical transmission in the visible region at room temperature has been isolated as a gamma-Fe(2)O(3)/polymer nanocomposite. The synthesis is carried out in an ion-exchange resin at 60 degrees C. Magnetization and susceptibility data demonstrate loading-dependent saturation moments as high as 46 electromagnetic units per gram and superparamagnetism for lower loadings where particle sizes are less than 100 angstroms. Optical absorption studies show that the small-particle form of gamma-Fe(2)O(3) is considerably more transparent to visible light than the single-crystal form. The difference in absorption ranges from nearly an order of magnitude in the "red" spectral region to a factor of 3 at 5400 angstroms. The magnetization of the nanocomposite is greater by more than an order of magnitude than those of the strongest room-temperature transparent magnets, FeBO(3) and FeF(3).