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As we age, blood stem cells, the essential source of new blood cells in the body, can accumulate genetic mutations. Now, scientists have not only discovered the mechanism that fuels their unchecked growth but have also found a way to stop it. The study reveals that a common aging-associated mutation in the gene Dnmt3a boosts the power-generating function of mitochondria in blood stem cells. This mutation allows the cells to make copies of themselves more readily than normal and creates fertile ground for the development of clonal hematopoiesis, a condition that dramatically increases the risk of heart disease, blood cancers,...

Mitochondrial dysfunction in β-cells can cause their immaturity and impaired insulin production, contributing to diabetes. Researchers identified a stress response triggered by damaged mitochondria that prevents these cells from functioning properly, but blocking the response with a drug restored their ability to control glucose in mice. Mitochondrial stress disrupts insulin production in diabetes, but reversing the damage may restore β-cell function. Mitochondria are essential for generating the energy that fuels cells and enables them to function. However, mitochondrial defects are linked to the development of diseases such as type 2 diabetes. Patients with this disorder either cannot produce enough insulin...

Researchers have discovered a mechanism in our cells that is essential to energy production in the muscles. "We have identified a new, important mechanism for energy production of the muscle cells and shown that it is activated by physical exercise—regardless of age, gender and state of health," says Associate Professor Lykke Sylow. The researchers demonstrate that a specific protein plays a key role in the energy production taking place in the cells' energy factory, the mitochondria. And they were surprised to find that through fitness training (so-called aerobic exercise), it is in fact possible to circumvent the role of this...

A substance naturally occurring in pomegranates, strawberries and walnuts can improve memory and treatment of Alzheimer's disease, a new study concludes. Forgetfulness, difficulty finding words and confusion about time and place. These are some of the most common symptoms of Alzheimer's disease. Now researchers have discovered that an ordinary fruit can help. "Our study on mouse models with AD shows that urolithin A can alleviate memory problems and other consequences of dementia," says Vilhelm Bohr. "Even though the study was conducted on mouse models, the prospects are positive. So far, research has shown promising results for the substance in the...

Human cells showing cell nuclei (cyan), mitochondria (magenta), and the Coxiella burnetii protein MceF (yellow). The figure evidences the co-location of MceF with cellular mitochondria. Credit: Robson Kriiger Loterio Researchers have discovered a previously unidentified protein with antioxidant properties produced by Coxiella burnetii, a Gram-negative intracellular bacterium. This breakthrough suggests potential new treatments for autoimmune diseases and cancer. Researchers at the University of São Paulo, in collaboration with Australian colleagues, have discovered a unique bacterial protein capable of keeping human cells healthy even when the cells have a heavy bacterial burden. This breakthrough holds the potential for developing new treatments...

Researchers have identified that a transient inflammatory pain causes mitochondrial and redox changes in sensory neurons that persist beyond pain resolution. These changes appear to predispose to a failure in resolving pain caused by subsequent inflammation. Additionally, targeting the cellular redox balance prevents and treats chronic inflammatory pain in rodents. Pain often persists in patients with an inflammatory disease, even after the inflammation has subsided. For some time, there have been clues that mitochondrial dysfunction may be involved. In a clinical study, approximately 70% of patients with heritable mitochondrial diseases develop chronic pain. To unravel the role of mitochondria in...

A team of reproductive biologists has found that spermidine, a polyamine metabolite, helps oocytes clear away damaged mitochondria in mice, thereby improving mitophagy during female reproductive aging. Prior research and anecdotal evidence have shown that many animals experience declining fertility as they grow older. In this new effort, the research team found a link between spermidine levels in aging mice and fertility issues. The researchers began by measuring spermidine levels in ovarian tissue samples of mice of different ages—they found that as the mice grew older, their levels of spermidine were reduced. They also noted that the quality of oocytes...

A study has unveiled a previously unrecognized role for an essential nutrient in shaping the cellular landscape for one of the body's first lines of defense against infection, immune cells called macrophages. The findings identifying a role for the nutrient choline under normal conditions and in response to an intestinal worm infection in mice could potentially have significant implications for other models of human infection, perhaps even cancer immunity. Dr. Morgan Fullerton explains that by blocking a specific part of metabolism the research team saw an unexpected defect emerge in macrophages—sentinel cells that are one of the immune system's star...

Nerve cells that make up the gray matter in our brain allow us to perform different tasks. They are interconnected millions of times by nerve fibers running deeper in the brain, called axons. Many of these axons are wrapped by a cellular "insulating tape." The insulating cover is made of myelin, a lipid-rich substance that coats axons in up to 150 layers. Together, axons and myelin form what is known as white matter. When a signal is transmitted from one cell to the other by means of an electrical nerve impulse, it literally jumps from one node to the next....

Britain’s fertility regulator has confirmed the births of the U.K.'s first babies created using an experimental technique combining DNA from three peopleBritain's fertility regulator on Wednesday confirmed the births of the U.K.'s first babies created using an experimental technique combining DNA from three people, an effort to prevent the children from inheriting rare genetic diseases. The Human Fertilization and Embryology Authority said fewer than five babies have been born this way in the U.K. but did not provide further details to protect the families' identities. The news was first reported by the Guardian newspaper. In 2015, the U.K. became the...

Supplementing GlyNAC—a combination of glycine and N-acetylcysteine as precursors of the natural antioxidant glutathione—improved or reversed age-associated cognitive decline in old mice and improved multiple associated defects in the aging brain. Sekhar and his team worked with three groups of mice. Two groups were aged naturally side-by-side until they were 90 weeks old, which is similar to a 70-year-old person. At 90 weeks of age, both groups of old mice were evaluated for their cognitive abilities, such as remembering the correct route in a maze that leads to a food reward. These results were compared to those of young mice,...

For years, Sharissa Derricott, 30, had no idea why her body seemed to be failing. At 21, a surgeon replaced her deteriorated jaw joint. She’s been diagnosed with degenerative disc disease and fibromyalgia, a chronic pain condition. Her teeth are shedding enamel and cracking. None of it made sense to her until she discovered a community of women online who describe similar symptoms and have one thing in common: All had taken a drug called Lupron. Thousands of parents chose to inject their daughters with the drug, which was approved to shut down puberty in young girls but also is...

The words that researchers use to describe their results can be harnessed to discover potential new treatments for Parkinson's disease, according to a new study. The study employed an artificial intelligence (AI) system to identify an existing anti-cholesterol drug that has the ability to promote disposal of mitochondria, energy-making components of the cell which are damaged in the disease. The full pathogenic pathway leading to Parkinson's disease (PD) is unknown, but one clear contributor is mitochondrial dysfunction and the inability to dispose of defective mitochondria, a process called mitophagy. At least five genes implicated in PD are linked to impaired...

Urolithin A, a metabolite of ellagitannins in pomegranates, boosts immune cells’ ability to combat tumors by inducing a process known as mitophagy. STORY AT-A-GLANCE Urolithin A (UA) has emerged as a powerhouse player in the fight against cancer, as it may naturally boost tumor-fighting immune cells. UA is a metabolite of ellagitannins in pomegranates that has anti-inflammatory and anticancer effects. UA “recycles and renews mitochondria” by inducing a biological pathway known as mitophagy—the process of cleaning out your mitochondria, allowing them to function at their best. This changes T cells’ genetic program, making them more able to fight tumors. In...

Many cardiovascular diseases, such as atherosclerosis, or "hardening of the arteries," correlate to mitochondrial dysfunction and endothelial impairment in the tissues of the heart and blood vessels. Despite a significant improvement in therapies to treat cardiovascular disease, there is an unmet need to investigate mitochondria as a therapeutic target. A review published recently in the International Journal of Molecular Sciences explores the existing literature on relevant studies and makes recommendations for further study. The authors of the paper propose a closer examination of this relationship between mitochondrial dysfunction, endothelial impairment, and atherosclerosis is necessary in order to identify new precision...

Fearfully and wonderfully madeESSAY | Elegant molecular machines at the center of life belie Darwin’s theoryAt a recent conference, I watched a computer simulation of the most important machine in the world: ATP synthase. Without it, no life can exist. In the cells of every organism on Earth, from bluebird to blue whale, from amoeba to alfalfa to Aunt Millie, this molecular machine packages energy for cells to use, like AA batteries for so many game systems.No batteries, no game.I sat halfway back in the room on the center aisle, amid the hundred-odd scientists and casually dressed grad students watching...

Immature Blood Cells Leukemia Researchers have discovered potential new drugs that work in concert with other drugs to deliver a deadly one-two punch to leukemia. New study highlights potential of mitochondria-targeted chemotherapies. Scientists have discovered promising new drugs that work in concert with other drugs to deliver a deadly one-two punch to leukemia. The researchers are from Rice University and the University of Texas MD Anderson Cancer Center. Although the potential drugs are still years away from being tested in cancer patients, a study published recently in the journal Leukemia underscores their potential and the innovative methods that led to...

Mitochondria are the power plants of cells, and they contain their own genetic material and RNA molecules. Scientists have now discovered that certain modifications in mitochondrial RNA boost the invasive spread of cancer cells by supporting protein synthesis in mitochondria. They have established that a specific gene expression signature correlating with high levels of mitochondrial RNA modifications is associated with metastasis and poor prognosis in patients with head and neck cancer. When the researchers blocked the responsible RNA modifying enzyme in cancer cells, the number of metastases was reduced. Certain antibiotics that suppress protein synthesis in mitochondria were also able...

An oral supplement intended to stimulate a natural body process appears to promote muscle endurance and mitochondrial health in humans. New research suggests that the supplement, urolithin A, may help improve or prolong muscle activity in people who are aging or who have diseases that make exercise difficult. Urolithin A is a byproduct of a person's gut bacteria and a diet comprising polyphenols found in pomegranates, berries and nuts. The compound also is produced and sold by dietary supplement companies. Supplemental urolithin A has been shown in animal tests and molecular studies of humans to stimulate mitophagy, a process that...

Almost all cells regulate their biological processes over a 24-hour period, otherwise called a cell's circadian rhythm. To do so, cells use a biological clock that cycles different genes on and off throughout the day and night. Scientists already know that our metabolic health can suffer when our biological clock breaks down, due to shift work or sleep disorders, for example. However, it's unclear how exactly the biological clock of people with type 2 diabetes differs. Now a team of scientists has shown that the skeletal muscle in people with type 2 diabetes has a different circadian rhythm. They argue...