New research digs into the genetic drivers of heart failure, with an eye to precision treatments – STAT
Posted: August 11, 2022 at 2:14 am
When coronary arteries are blocked, starving the heart of blood, there are good medications and treatments to deploy, from statins to stents. Not so for heart failure, the leading factor involved in heart disease, the top cause of death worldwide.
Its whats on death certificates, said cardiologist Christine Seidman.
Seidman has long been interested in heart muscle disorders and their genetic drivers. She studies heart failure and other conditions that affect the myocardium the muscular tissue of the heart not the blood vessels where atherosclerosis and heart attacks come from, although their consequences are also felt in the myocardium, including heart failure.
advertisement
With her colleagues at Brigham and Womens Hospital and Harvard Medical School, she and a long list of international collaborators have been exploring the genetic underpinnings of heart failure. Based on experiments deploying a new technique called single-nucleus RNA sequencing on samples from heart patients, on Thursday they reported in Science their discovery of how genotypes change the way the heart functions.
Their work raises the possibility that some of the molecular pathways that lead to heart failure could be precisely targeted, in contrast to treating heart failure as a disease with only one final outcome.
advertisement
Were not there yet, but we certainly have the capacity to make small molecules to interfere with pathways that we think are deleterious to the heart in this setting, she said. To my mind, thats the way to drive precision therapeutics. We know the cause of heart failure. We intervene in a pathway that we know is activated. And for the first time, we have that information now from human samples, not from an experimental model.
Seidman talked with STAT about the research, including how snRNAseq solves the smoothie problem, and what it might mean for patients. The conversation has been edited for clarity and brevity.
What happens in heart failure?
The heart becomes misshapen in one of two ways. It either becomes hypertrophied, where the walls of heart muscle become thickened and the volume within the heart is diminished, in what we call hypertrophic cardiomyopathy. Or it becomes dilated, when the volume in the heart is expanded and the walls become stretched. I think of it as an overinflated balloon, and that is called dilated cardiomyopathy.
Hypertrophy and dilatation are known to cause the heart over time to have profoundly diminished functional capacity. And clinically, we call that heart failure, much more commonly arising from dilated cardiomyopathy.
What does it feel like to patients?
When we see patients clinically, theyre short of breath, they have fluid retention. When we look at their hearts, we see that the pump function is diminished. That has led to a hypothesis of heart failure as sort of the end stage of many different disorders, but eventually the heart walks down a final common pathway. Then you need a transplant or a left ventricular assist device, or youre going to die prematurely.
What can be done?
Heart failure is a truly devastating condition, and it can arise early in life, in middle age, and in older people. There is no treatment for it, no cure for it, except cardiac transplantation, of course, which provides a whole host of other problems.
How did you approach this problem?
One of the questions we wanted to answer is, are there signals that we can discern that say there are different pathways and there are molecules that are functioning in those pathways that ultimately converge for failure, but through different strategies of your heart?
We treat every patient with heart failure with diuretics. We give them a series of different medications to reduce the pressure against which the heart has to contract. Im clinically a cardiologist, but molecularly Im a geneticist, so it doesnt make sense. If your house is falling down because the bricks are sticking together or if its falling down because the roof leaks and the water is pooling, you do things differently.
Tell me how you used single-cell RNA sequencing to learn more.
Looking at RNA molecules gives us a snapshot of how much a gene is active or inactive at a particular time point. Until recently, we couldnt do that in the heart because the approach had been to take heart tissue, grind it all up, and look at the RNAs that are up or down. But that gives you what we call a smoothie: Its all the different component cells those strawberries, blueberries, bananas mixed together.
But theres a technology now called single-cell RNA sequencing. And that says, what are the RNAs that are up or down in the cardiomyocytes as compared to the smooth muscle cells, as compared to the fibroblasts, all of which are in the cells? You get a much more precise look at whats changing in a different cell type. And thats the approach that we use, because cardiomyocytes [the cells in the heart that make it contract] are very large. Theyre at least three times bigger than other cells. We cant capture the single cell it literally does not fit through the microfluidic device. And so we sequenced the nuclei, which is where the RNA emanates from.
What did you find?
There were some similarities, but what was remarkable was the degree of differences that we saw in cardiomyocytes, in endothelial cells, in fibroblasts. Theres a signature thats telling us I walked down this pathway as compared to a different one that caused the heart to fail, but through activation or lack of activation of different signals along the way.
And that to me is the excitement, because if we can say that, we can then go back and say, OK, what happens if we were to have tweaked the pathway in this genotype and a different pathway in a different genotype? Thats really what precision therapy could be about, and thats where we aim to get to.
Whats the next step?
It may be that several genotypes will have more similarities as compared to other genotypes. But understanding that, I think, will allow us to test in experimental models, largely in mice, but increasingly in cellular models of disease, in iPS [induced pluripotent stem] cells that we can now begin to use molecular technologies to silence a pathway and see what that does to the cardiomyocytes, or silence the fibroblast molecule and see what that does in that particular genotype.
To my mind, thats the way to drive precision therapeutics. We know the cause of heart failure. We intervene in a pathway that we know is activated. And for the first time, we have that information now from human samples, not from an experimental model.
What might this mean for patients?
If we knew that an intervention would make a difference thats where the experiments are we would intervene when we saw manifestations of disease. So the reason I can tell you with confidence that certain genes cause dilated cardiomyopathy is theres a long time between the onset of that expansion of the ventricle until you develop heart failure. So theres years for us to be able to stop it in its tracks or potentially revert the pathology, if we can do that.
What else can you say?
I would be foolish not to mention the genetic cause of dilated cardiomyopathy. Ultimately, if you know the genetic cause of dilated cardiomyopathy, this is where gene therapy may be the ultimate cure. Were not there yet, but we certainly have the capacity to make small molecules to interfere with pathways that we think are deleterious to the heart in this setting.
My colleagues have estimated that approximately 1 in 250 to 1 in 500 people may have an important genetic driver of heart muscle disease, cardiomyopathy. Thats a huge number, but not all of them will progress to heart failure, thank goodness. Around the world, there are 23 million people with heart failure. Its what ends up on most peoples death certificate. It is the most common cause of death.
Its a huge, huge burden. And there really is no cure for it except transplantation. We dont have a reparative capacity, so were going to have to know a cause and be able to intervene precisely for that cause.
Read the original post:
New research digs into the genetic drivers of heart failure, with an eye to precision treatments - STAT
- Gene Therapy Could Prevent Blindness [Last Updated On: June 10th, 2010] [Originally Added On: June 10th, 2010]
- Gene Brodland Sits with Cambridge Who's Who in a Revealing Interview [Last Updated On: June 16th, 2010] [Originally Added On: June 16th, 2010]
- Researchers Make Colon Cancer Breakthrough [Last Updated On: July 20th, 2010] [Originally Added On: July 20th, 2010]
- Pro abortion- Antiabortion myth8 - Fly to India for safe abortion! [Last Updated On: October 16th, 2010] [Originally Added On: October 16th, 2010]
- New Fertility Test / Whooping Cough Alert / Gene Therapy for Depression [Last Updated On: October 21st, 2010] [Originally Added On: October 21st, 2010]
- Alzheimer's Breakthrough? [Last Updated On: October 23rd, 2010] [Originally Added On: October 23rd, 2010]
- Audio Genetics Lab - Native Flute - MP3Tera Forums [Last Updated On: December 8th, 2010] [Originally Added On: December 8th, 2010]
- Gene Therapy - Cortical Studios [Last Updated On: May 8th, 2011] [Originally Added On: May 8th, 2011]
- There Shall Be Physicians for the Spirit: USC Institute for Genetic Medicine Art Gallery [Last Updated On: May 8th, 2011] [Originally Added On: May 8th, 2011]
- IRRI: Rice genetic diversity and discovery [Last Updated On: May 8th, 2011] [Originally Added On: May 8th, 2011]
- Research Symposium: Mork Depart - 2006 - Video 1 [Last Updated On: May 8th, 2011] [Originally Added On: May 8th, 2011]
- Mendelian Genetics [Last Updated On: May 8th, 2011] [Originally Added On: May 8th, 2011]
- Ayurveda [Last Updated On: May 8th, 2011] [Originally Added On: May 8th, 2011]
- Drs. Kaspar and MacKenzie discuss the promise and path forward for SMA Gene Therapy [Last Updated On: May 8th, 2011] [Originally Added On: May 8th, 2011]
- 3. Genetic Engineering [Last Updated On: May 8th, 2011] [Originally Added On: May 8th, 2011]
- Prof. Martinez Cruzado Lecture Part 3 "Amerindian Gene Study In Puerto Rico" [Last Updated On: May 8th, 2011] [Originally Added On: May 8th, 2011]
- Gene Therapy Research Makes Nationwide Children's Worthy of Wellstone Center [Last Updated On: May 8th, 2011] [Originally Added On: May 8th, 2011]
- Gene Therapy Example [Last Updated On: May 9th, 2011] [Originally Added On: May 9th, 2011]
- Sweet Tooth Gene [Last Updated On: May 9th, 2011] [Originally Added On: May 9th, 2011]
- OHSU's video of new gene therapy method developed at the Oregon National Primate Research Center [Last Updated On: May 9th, 2011] [Originally Added On: May 9th, 2011]
- Gregor Mendel's Punnett Squares [Last Updated On: May 9th, 2011] [Originally Added On: May 9th, 2011]
- Ethical Concerns With Genetic Engineering [Last Updated On: May 9th, 2011] [Originally Added On: May 9th, 2011]
- Dr. Laura Niklason on the importance of her AFAR grants for telomerase gene therapy research [Last Updated On: May 9th, 2011] [Originally Added On: May 9th, 2011]
- What is the future of genetic medicine? [Last Updated On: May 9th, 2011] [Originally Added On: May 9th, 2011]
- Prof. Martinez Cruzado Lecture Part 2 "Amerindian Gene Study In Puerto Rico" [Last Updated On: May 9th, 2011] [Originally Added On: May 9th, 2011]
- Jewish DNA - Genetic Research and The Origins of the Jewish People [Last Updated On: May 9th, 2011] [Originally Added On: May 9th, 2011]
- Future of genetic engineering - by Futurist Dr Patrick Dixon. Genetic mutations and genetic disorders. Gene science by conference keynote speaker [Last Updated On: May 11th, 2011] [Originally Added On: May 11th, 2011]
- annstewart82's Genetic Medicine and God [Last Updated On: May 13th, 2011] [Originally Added On: May 13th, 2011]
- Genetic research could unlock breeding seasons in sheep [Last Updated On: May 13th, 2011] [Originally Added On: May 13th, 2011]
- Genetics 101 Part 1: What are genes? [Last Updated On: May 13th, 2011] [Originally Added On: May 13th, 2011]
- Molecular and Cellular Foundations of Medicine, 1 of 2 [Last Updated On: May 13th, 2011] [Originally Added On: May 13th, 2011]
- Dan Arking of Johns Hopkins Medicine [Last Updated On: May 17th, 2011] [Originally Added On: May 17th, 2011]
- Genetics : How Is Gene Therapy Done? [Last Updated On: May 19th, 2011] [Originally Added On: May 19th, 2011]
- Gene Therapy Shows Promise for Blindness [Last Updated On: May 19th, 2011] [Originally Added On: May 19th, 2011]
- Tomato suicide gene therapy [Last Updated On: May 19th, 2011] [Originally Added On: May 19th, 2011]
- Cancer Alternative Treatment - Gene Therapy for Cancer a Report from Channel 4 News [Last Updated On: May 19th, 2011] [Originally Added On: May 19th, 2011]
- Muscular Dystrophy Gene Therapy: ScienCentral News Video [Last Updated On: May 19th, 2011] [Originally Added On: May 19th, 2011]
- Sickle Cell Anemia -- Hope from Gene Therapy [Last Updated On: May 19th, 2011] [Originally Added On: May 19th, 2011]
- Challenges of gene therapy [Last Updated On: May 19th, 2011] [Originally Added On: May 19th, 2011]
- Pain Gene Therapy [Last Updated On: May 19th, 2011] [Originally Added On: May 19th, 2011]
- Gene therapy success 'reverses' blindness [Last Updated On: May 19th, 2011] [Originally Added On: May 19th, 2011]
- DNA Gene Therapy [Last Updated On: May 19th, 2011] [Originally Added On: May 19th, 2011]
- The Neural Circuitry of Perception [Last Updated On: May 19th, 2011] [Originally Added On: May 19th, 2011]
- Resetting Metabolism- Nuclear Receptors and AMPK: A Lecture by Ronald Evans, PhD [Last Updated On: May 19th, 2011] [Originally Added On: May 19th, 2011]
- Islands at Risk (Part 2) - Genetic Engineering in Hawai'i [Last Updated On: May 19th, 2011] [Originally Added On: May 19th, 2011]
- Gene Therapy journal videocast from ASGCT 2011 Xiao Xiao on gene therapy for muscular dystrophy [Last Updated On: May 20th, 2011] [Originally Added On: May 20th, 2011]
- HYBRID HUMANS-Hair Follicle Gene Therapy [Last Updated On: May 20th, 2011] [Originally Added On: May 20th, 2011]
- Genetics 101 Part 4: What is phenotype? [Last Updated On: May 20th, 2011] [Originally Added On: May 20th, 2011]
- Lloyd Pye - Ancient Genetic Engineering [Last Updated On: May 20th, 2011] [Originally Added On: May 20th, 2011]
- Study Designs: Genetic Association Studies [Last Updated On: May 20th, 2011] [Originally Added On: May 20th, 2011]
- Gene Therapy for Genetic Disease: The Long and Winding Road [Last Updated On: May 20th, 2011] [Originally Added On: May 20th, 2011]
- Introduction to Population Genetics [Last Updated On: May 20th, 2011] [Originally Added On: May 20th, 2011]
- Islands at Risk (Part 1) - Genetic Engineering in Hawai'i [Last Updated On: May 20th, 2011] [Originally Added On: May 20th, 2011]
- Genetics Based Research on Treatment-Resistant Epilepsy [Last Updated On: May 20th, 2011] [Originally Added On: May 20th, 2011]
- Science in Action: Gene Therapy for Color Blindness [Last Updated On: May 21st, 2011] [Originally Added On: May 21st, 2011]
- Gregg Semenza of Johns Hopkins Medicine on HIF 1 [Last Updated On: May 21st, 2011] [Originally Added On: May 21st, 2011]
- The Sleepiness Gene [Last Updated On: May 21st, 2011] [Originally Added On: May 21st, 2011]
- Blind Gene Therapy [Last Updated On: May 21st, 2011] [Originally Added On: May 21st, 2011]
- Richard Dawkins and Dr Yan on genetic ancestry (extended version) - Bang Goes the Theory - BBC One [Last Updated On: May 22nd, 2011] [Originally Added On: May 22nd, 2011]
- Joshua Mendell of Johns Hopkins Medicine [Last Updated On: May 22nd, 2011] [Originally Added On: May 22nd, 2011]
- Genetic/Genomic Faculty Champion Initiative (PM session) [Last Updated On: May 22nd, 2011] [Originally Added On: May 22nd, 2011]
- euronews science - Epigenetics [Last Updated On: May 22nd, 2011] [Originally Added On: May 22nd, 2011]
- The Genetic Age, Panel 1 [Last Updated On: May 22nd, 2011] [Originally Added On: May 22nd, 2011]
- Biobanking and Bioethics: When Genetics Research Hits the Courts [Last Updated On: May 22nd, 2011] [Originally Added On: May 22nd, 2011]
- Gene Therapy journal videocast from ASGCT 2011 Darren Wolfe on gene therapy for pain.m4v [Last Updated On: May 23rd, 2011] [Originally Added On: May 23rd, 2011]
- Genetics 101 Part 3: Where do your genes come from? [Last Updated On: May 23rd, 2011] [Originally Added On: May 23rd, 2011]
- ASHG 2010 Mtg.: "Complex Disease Genetics Research in Populations" (Dr. Carlos Bustamente) [Last Updated On: May 23rd, 2011] [Originally Added On: May 23rd, 2011]
- Public Talk - Prof Leonard Seymour, Oxford [Last Updated On: May 23rd, 2011] [Originally Added On: May 23rd, 2011]
- A New Era in Medicine: Genetics [Last Updated On: May 23rd, 2011] [Originally Added On: May 23rd, 2011]
- Genetic Engineering Animation [Last Updated On: May 23rd, 2011] [Originally Added On: May 23rd, 2011]
- Linda Brzustowicz - Genetic Causes of Schizophrenia [Last Updated On: May 23rd, 2011] [Originally Added On: May 23rd, 2011]
- Hadassah Gene Therapy Center [Last Updated On: May 23rd, 2011] [Originally Added On: May 23rd, 2011]
- Gene Therapy journal videocast from ASGCT 2011 Robin Ali on gene therapy for retinal disease [Last Updated On: May 23rd, 2011] [Originally Added On: May 23rd, 2011]
- UF cardiologists study gene-modified stem cells to help Dobermans with common heart condition [Last Updated On: May 23rd, 2011] [Originally Added On: May 23rd, 2011]
- Akhilesh Pandey of Johns Hopkins Medicine [Last Updated On: May 23rd, 2011] [Originally Added On: May 23rd, 2011]
- China's Cancer Drug - China [Last Updated On: May 23rd, 2011] [Originally Added On: May 23rd, 2011]
- Genetic Therapy Restored Boy's Sight [Last Updated On: May 24th, 2011] [Originally Added On: May 24th, 2011]
- Molecular and Cellular Foundations of Medicine Class, 2 of 2 [Last Updated On: May 24th, 2011] [Originally Added On: May 24th, 2011]
- Talking Research - Professor George Ebers - Vitamin D and genetics in MS [Last Updated On: May 24th, 2011] [Originally Added On: May 24th, 2011]
- Designing Humanity - Genetic Engineering [Last Updated On: May 30th, 2011] [Originally Added On: May 30th, 2011]