Nanogels For Heart Attack Patients

Heart disease and heart-related illnesses are a leading cause of death around the world, but treatment options are limited. Now, one group reports in ACS Nano that encapsulating stem cells in a nanogel could help repair damage to the heart.

Myocardial infarction, also known as a heart attack, causes damage to the muscular walls of the heart. Scientists have tried different methods to repair this damage. For example, one method involves directly implanting stem cells in the heart wall, but the cells often don’t take hold, and sometimes they trigger an immune reaction. Another treatment option being explored is injectable hydrogels, substances that are composed of water and a polymer. Naturally occurring polymers such as keratin and collagen have been used but they are expensive, and their composition can vary between batches. So Ke Cheng, Hu Zhang, Jinying Zhang and colleagues wanted to see whether placing stem cells in inexpensive hydrogels with designed tiny pores that are made in the laboratory would work.

The team encapsulated stem cells in nanogels, which are initially liquid but then turn into a soft gel when at body temperature. The nanogel didn’t adversely affect stem cell growth or function, and the encased stem cells didn’t trigger a rejection response. When these enveloped cells were injected into mouse and pig hearts, the researchers observed increased cell retention and regeneration compared to directly injecting just the stem cells. In addition, the heart walls were strengthened. Finally, the group successfully tested the encapsulated stem cells in mouse and pig models of myocardial infarction.

Source: https://www.acs.org/
A
ND
https://global.ncsu.edu/

Nanoparticles From Air Pollution Travel Into Blood To Cause Heart Disease

Inhaled nanoparticles – like those released from vehicle exhausts – can work their way through the lungs and into the bloodstream, potentially raising the risk of heart attack and stroke, according to new research part-funded by the British Heart Foundation. The findings, published today in the journal ACS Nano, build on previous studies that have found tiny particles in air pollution are associated with an increased risk of cardiovascular disease, although the cause remains unproven. However, this research shows for the first time that inhaled nanoparticles can gain access to the blood in healthy individuals and people at risk of stroke. Most worryingly, these nanoparticles tend to build-up in diseased blood vessels where they could worsen coronary heart disease – the cause of a heart attack.

It is not currently possible to measure environmental nanoparticles in the blood. So, researchers from the University of Edinburgh, and the National Institute for Public Health and the Environment in the Netherlands, used a variety of specialist techniques to track the fate of harmless gold nanoparticles breathed in by volunteers. They were able to show that these nanoparticles can migrate from the lungs and into the bloodstream within 24 hours after exposure and were still detectable in the blood three months later. By looking at surgically removed plaques from people at high risk of stroke they were also able to find that the nanoparticles accumulated in the fatty plaques that grow inside blood vessels and cause heart attacks and strokesCardiovascular disease (CVD) – the main forms of which are coronary heart disease and stroke – accounts for 80% of all premature deaths from air pollution.

Blood_Heart_Circulation

It is striking that particles in the air we breathe can get into our blood where they can be carried to different organs of the body. Only a very small proportion of inhaled particles will do this, however, if reactive particles like those in air pollution then reach susceptible areas of the body then even this small number of particles might have serious consequences,”  said Dr Mark Miller, Senior Research Fellow at the University of Edinburgh who led the study.

Source: http://www.cvs.ed.ac.uk/

SiO2 Nanoparticles Cause Cardiovascular Disease

Nanoparticles, extremely tiny particles measured in billionths of a meter, are increasingly everywhere, and especially in biomedical products. Their toxicity has been researched in general terms, but now a team of Israeli scientists has for the first time found that exposure nanoparticles> (NPs) of silicon dioxide (SiO2) can play a major role in the development of cardiovascular diseases when the nanoparticles cross tissue and cellular barriers and also find their way into the circulatory system.
heart
Environmental exposure to nanoparticles is becoming unavoidable due to the rapid expansion of nanotechnology,” says the study’s lead author, Prof. Michael Aviram, of the Technion Faculty of Medicine, “This exposure may be especially chronic for those employed in research laboratories and in high tech industry where workers handle, manufacture, use and dispose of nanoparticles. Products that use silica-based nanoparticles for biomedical uses, such as various chips, drug or gene delivery and tracking, imaging, ultrasound therapy, and diagnostics, may also pose an increased cardiovascular risk for consumers as well.”

The study has been published in the December 2014 issue of Environmental Toxicology.
The research team was comprised of scientists from the Technion Rappaport Faculty of Medicine, Rambam Medical Center, and the Center of Excellence in Exposure Science and Environmental Health (TCEEH).
Source: http://www.ats.org/

Nano Pacemaker To Extend Cardiac Patients Life

A new type of pacemaker develped by a research team from the University of Bath and the Univerity of Bristol – U.K. – could revolutionise the lives of millions people who live with heart failure in the world. The British Heart Foundation (BHF) is awarding funding to researchers developing a new type of heart pacemaker that modulates its pulses to match breathing rates. Currently, the pulses from pacemakers are set at a constant rate when fitted which doesn’t replicate the natural beating of the human heart. The normal healthy variation in heart rate during breathing is lost in cardiovascular disease and is an indicator for sleep apnoea, cardiac arrhythmia, hypertension, heart failure and sudden cardiac death.
The device works by saving the heart energy, improving its pumping efficiency and enhancing blood flow to the heart muscle itself. Pre-clinical trials suggest the device gives a 25 per cent increase in the pumping ability, which is expected to extend the life of patients with heart failure.


This is a multidisciplinary project with strong translational value. By combining fundamental science and nanotechnology we will be able to deliver a unique treatment for heart failure which is not currently addressed by mainstream cardiac rhythm management devices,” explains Dr Alain Nogaret, Senior Lecturer in Physics at the University of Bath.
One aim of the project is to miniaturise the pacemaker device to the size of a postage stamp and to develop an implant that could be used in humans within five years.
The findings of the research have been published recently in the Journal of Neuroscience Methods.

Source: http://www.bath.ac.uk/

Nanoparticles Target Arteries To fight Heart Disease

Clemson University – South Carolina – researchers have developed nanoparticles that can deliver drugs targeting damaged arteries, a non-invasive method to fight heart disease. Heart disease is the leading cause of death in the U.S., according to the Centers for Disease Control and Prevention. One of the standard ways to treat clogged and damaged arteries currently is to implant vascular stents, which hold the vessels open and release such drugs as paclitaxel. The researchers, led by Clemson bioengineering professor Naren Vyavahare, hope their advanced nanoparticles could be used alongside stents or in lieu of them.
hypertension
Healthy arteries have elastic fibers that provide elasticity. They are like rubber bands in the tissue that allow expansion and recoil during blood flow,” Vyavahare said. “In most cardiovascular diseases, elastic fibers in arteries get damaged, creating hooks that can be used to target drugs.
Source: http://newsstand.clemson.edu/

Nano-hitchhikers Track Stem Cells Entering Heart

The promise of repairing damaged hearts through regenerative medicine — infusing stem cells into the heart in the hope that these cells will replace worn out or damaged tissue — has yet to meet with clinical success. But a highly sensitive visualization technique developed by Stanford University School of Medicine scientists may help speed that promise’s realization.
stem_cell

All stem cell researchers want to get the cells to the target site, but up until now they’ve had to shoot blindly,” said Gambhir, who is also the Virginia and D.K. Ludwig Professor in Cancer Research and director of the Molecular Imaging Program at Stanford. “With this new technology, they wouldn’t have to. For the first time, they would be able to observe in real time exactly where the stem cells they’ve injected are going and monitor them afterward. If you inject stem cells into a person and don’t see improvement, this technique could help you figure out why and tweak your approach to make the therapy better.”

Source: http://med.stanford.edu/

How Good Cholesterol Turns Bad

Researchers with the U.S. Department of Energy (DOE)’s Lawrence Berkeley National Laboratory (Berkeley Lab) have found new evidence to explain how cholesteryl ester transfer protein (CETP) mediates the transfer of cholesterol from “good” high density lipoproteins (HDLs) to “bad” low density lipoproteins (LDLs). These findings point the way to the design of safer, more effective next generation CETP inhibitors that could help prevent the development of heart disease.

Gang Ren, a materials physicist and electron microscopy expert with Berkeley Lab’s Molecular Foundry, a DOE nanoscience research center, led a study in which the first structural images of CETP interacting with HDLs and LDLs were recorded. The images and structural analyses support the hypothesis that cholesterol is transferred from HDLs to LDLs via a tunnel running through the center of the CETP molecule. “Our images show that CETP is a small (53 kilodaltons) banana-shaped asymmetric molecule with a tapered N-terminal domain and a globular C-terminal domain,” Ren says. “We discovered that the CETP’s N-terminal penetrates HDL and its C-terminal interacts with LDL forming a ternary complex. Structure analyses lead us to hypothesize that the interaction may generate molecular forces that twist the terminals, creating pores at both ends of the CETP. These pores connect with central cavities in the CETP to form a tunnel that serves as a conduit for the movement of cholesterol from the HDL.”

Source: http://newscenter.lbl.gov/news-releases/2012/02/21/how-good-cholesterol-turns-bad/