Stem cells to patch up a heart attack
July 1, 2019
Researchers in England are reporting that they have grown heart patches in the lab that are safe to move into trials in people with hearts damaged by a heart attack. These patches could one day cure debilitating heart failure, which is a major killer in the United States. At Imperial College London, scientists have developed a way to grow thumb-size patches of heart tissue (3cm x 2cm) that contain up to 50 million human stem cells. The stem cells are programmed to turn into working heart muscle that can be seen beating.
One or more of these patches could be implanted in the heart of someone after they’ve had a heart attack to limit, and even reverse, the loss of the heart’s pumping ability, according to the researchers. During a heart attack, the heart is starved of vital nutrients and oxygen, killing off parts of the heart muscle. This weakens the heart and can eventually lead to heart failure.
The patches have been shown to be safe in rabbits and they led to an improvement in the function of the heart after a heart attack. After a period of up to four weeks, detailed heart scans showed that the hearts’ left ventricle (the chamber responsible for pumping blood through the aorta) was recovering without developing any abnormal heart rhythms, which is a potential side effect of other stem cell delivery methods. Importantly, the patches appeared to be nourished by blood vessels growing into them from the recipient heart.
Once sewn in place, the patches are intended to physically support the damaged heart muscle and help it pump more efficiently by releasing natural chemicals that stimulate the heart cells to repair and regenerate. The patches were developed in response to somewhat disappointing results from around the world when stem cells were just directly injected into damaged heart muscle. Without a fixed ‘patch’, stem cells are quickly cleared from the heart and aren’t able to cause significant levels of repair.
“One day, we hope to add heart patches to the treatments that doctors can routinely offer people after a heart attack. We could prescribe one of these patches alongside medicines for someone with heart failure, which you could take from a shelf and implant straight into a person,” said Dr. Richard Jabbour, who carried out the research at the London BHF Centre of Regenerative Medicine, London, England.
Unsalted tomato juice may pack a hidden benefit
Drinking unsalted tomato juice on a regular basis may help lower blood pressure and LDL cholesterol. In a study published in Food Science & Nutrition, researchers in Japan showed that drinking unsalted tomato juice lowered blood pressure and LDL cholesterol in adults at risk of cardiovascular disease.
In the study, 184 male and 297 female participants were provided with as much unsalted tomato juice as they wanted throughout one year. At the end of the study, blood pressure in 94 participants with untreated prehypertension or hypertension dropped significantly. Systolic blood pressure lowered from an average of 141.2 to 137.0 mmHg, and diastolic blood pressure lowered from an average of 83.3 to 80.9 mmHg. LDL cholesterol levels in 125 participants with high cholesterol decreased from an average of 155.0 to 149.9 mg/dL. These beneficial effects were similar among men and women and among different age groups.
“To the best of our knowledge, the current study is the first to investigate the effects of tomato or tomato product intake on cardiovascular disease risk markers over the course of a year and over a wide age range,” the authors wrote. They noted that tomato juice is an affordable and readily available product that may be applied as a nutritional intervention to prevent heart attacks and strokes in individuals at high risk.
The researchers theorize that lycopene may be playing a role. Lycopene is found in abundance in all tomato products and is well known for its strong antioxidant activity and the inhibition of LDL oxidation. Several epidemiological studies have suggested that lycopene could contribute to the prevention of atherosclerosis, as well as heart attacks and strokes.
Home exercise program reduces falls in at-risk seniors
The best way to prevent falls may be to take a proactive step. A new 12-month clinical trial has found that an in-home exercise program can reduce subsequent falls in high-risk seniors by 36%. The study, which was conducted in Vancouver, Canada, found a reduction in fall rate and a small improvement in cognitive function in older adults who received strength and balance training through the clinical trial.
“When we think about falls we often think about loss of muscle strength and poor balance,” said Dr. Teresa Liu-Ambrose, who is the principal investigator at the Vancouver Coastal Health Research Institute and professor in the department of physical therapy at the University of British Columbia, Vancouver, Canada. “However, the ability to remain upright and not fall is also dependent on cognitive abilities, calculating how far to lift your foot to get over a curb, making a decision as to when to cross the road, and paying attention to your physical environment while you are having a conversation.”
Falls increase risk of injury and loss of independence for older adults. Exercise is a widely recommended fall prevention strategy, but whether it can reduce subsequent falls in those who have previously fallen is not well established. The study involved 344 adults (70 and older), who had been referred to the Falls Prevention Clinic following a fall that had resulted in a visit to a medical facility, such as an emergency room. Participants had a history of falls, with an average of three prior falls per person, and generally had symptoms of frailty and limited mobility.
The researchers say this is a unique study because the participants were at very high risk for losing their independence. They had both mobility and cognitive impairments and another fall could mean the inability to live in their own homes.
John Schieszer is an award-winning national journalist and radio and podcast broadcaster of The Medical Minute. He can be reached at firstname.lastname@example.org.