Medical Frailty of a person is associated with the amount of mitochondrial DNA (mtDNA) found in the his or her blood, suggests a new research from The John Hopkins University. This DNA may prove to be a useful predictor of overall risk of frailty and death from any cause 10 to 15 years before symptoms appear.
The investigators say their findings contribute to the scientific understanding of aging and may lead to a test that could help identify at-risk individuals whose physical fitness can be improved with drugs or lifestyle changes. A summary of the research was published online Dec. 4 in the Journal of Molecular Medicine.
CoQ10
Vitamin-like CoQ10 helps generate energy for the cells to function at their optimum level. Secondary to its role in energy production, CoQ10 also functions as a potent antioxidant.
Advertisement
"We don't know enough yet to say whether the relationship is one of correlation or causation," says Dan Arking, Ph.D., associate professor of genetic medicine. "But either way, mitochondrial DNA could be a very useful biomarker in the field of aging."
Mitochondria are structures within cells often referred to as "power houses" because they generate most of cells' energy. Unlike other cell structures, they contain their own DNA -- separate from that enclosed in the nucleus -- in the form of two to 10 small, circular chromosomes that code for 37 genes necessary for mitochondrial function. There are 10 to thousands of mitochondria per cell, depending on a cell's energy needs.
![Mom’s Genes Help Women To Outlive Men]( "Mom’s Genes Help Women To Outlive Men")
Mitochondrial DNA might hold the key to increased longevity in females and shorter lifespan in males.
Previous research from Arking's laboratory linked genetic differences in mtDNA to increased frailty and reduced muscle strength in older individuals. Medically speaking, frailty refers to a well-recognized collection of aging symptoms that include weakness, decreased energy, lower activity levels and weight loss. To further test this link, Arking's team analyzed the amount of mtDNA in blood samples collected for two large, human studies that began in the late 1980s and tracked individuals' health outcomes for 10 to 20 years.
After calculating how much mtDNA each sample contained relative to the amount of nuclear DNA, the team looked at measures of frailty and health status gathered on the studies' participants over time.
On average, Arking says, subjects who met the criteria for frailty had 9 percent less mtDNA than nonfrail participants. And, when grouped by amount of mtDNA, white participants in the bottom one-fifth of the study population were 31 percent more likely to be frail than participants in the top one-fifth.
"It makes intuitive sense that decreased mtDNA is associated with bad health outcomes," says Arking. "As we age, our energy reserves decrease, and we become more susceptible to all kinds of health problems and disease."
The researchers also analyzed the age at which participants died. In one of the studies, high levels of mtDNA corresponded to a median of 2.1 extra years of life compared to those with the lowest levels of mtDNA. Using data from both studies, the team found that those with mtDNA levels in the bottom one-fifth of the population were 47 percent more likely to die of any cause during the study period than were those in the top one-fifth. They also found that women had an average of 21 percent more mtDNA than men.
According to Arking, this could play a small role in why women live two to four years longer than men on average. Arking says that the research team would like to take repeated blood samples from individuals over several years to learn if and by how much mtDNA levels decrease over time. What the investigators saw in the current study is that, averaged over the population, an increase of 10 years in age corresponded to 2.5 percent less mtDNA.
The authors say they hope that mtDNA tests could detect people at risk of frailty 10 to 15 years before they begin to experience symptoms so that doctors can prescribe strength training or other interventions. If low numbers of mitochondria are shown to cause or contribute to frailty, the team can use their simple test on lab-grown cells to assess the effectiveness of new drugs to increase the numbers of mitochondria.
Source: Eurekalert
Mom’s Genes Help Women To Outlive Men
Mitochondrial DNA might hold the key to increased longevity in females and shorter lifespan in males.
Advertisement
Previous research from Arking's laboratory linked genetic differences in mtDNA to increased frailty and reduced muscle strength in older individuals. Medically speaking, frailty refers to a well-recognized collection of aging symptoms that include weakness, decreased energy, lower activity levels and weight loss. To further test this link, Arking's team analyzed the amount of mtDNA in blood samples collected for two large, human studies that began in the late 1980s and tracked individuals' health outcomes for 10 to 20 years.
After calculating how much mtDNA each sample contained relative to the amount of nuclear DNA, the team looked at measures of frailty and health status gathered on the studies' participants over time.
On average, Arking says, subjects who met the criteria for frailty had 9 percent less mtDNA than nonfrail participants. And, when grouped by amount of mtDNA, white participants in the bottom one-fifth of the study population were 31 percent more likely to be frail than participants in the top one-fifth.
"It makes intuitive sense that decreased mtDNA is associated with bad health outcomes," says Arking. "As we age, our energy reserves decrease, and we become more susceptible to all kinds of health problems and disease."
The researchers also analyzed the age at which participants died. In one of the studies, high levels of mtDNA corresponded to a median of 2.1 extra years of life compared to those with the lowest levels of mtDNA. Using data from both studies, the team found that those with mtDNA levels in the bottom one-fifth of the population were 47 percent more likely to die of any cause during the study period than were those in the top one-fifth. They also found that women had an average of 21 percent more mtDNA than men.
According to Arking, this could play a small role in why women live two to four years longer than men on average. Arking says that the research team would like to take repeated blood samples from individuals over several years to learn if and by how much mtDNA levels decrease over time. What the investigators saw in the current study is that, averaged over the population, an increase of 10 years in age corresponded to 2.5 percent less mtDNA.
The authors say they hope that mtDNA tests could detect people at risk of frailty 10 to 15 years before they begin to experience symptoms so that doctors can prescribe strength training or other interventions. If low numbers of mitochondria are shown to cause or contribute to frailty, the team can use their simple test on lab-grown cells to assess the effectiveness of new drugs to increase the numbers of mitochondria.
Source: Eurekalert
Antioxidant MitoQ Can Prevent Liver Damage from Alcohol
A new antioxidant MitoQ could pave the way for new methods of cirrhosis and cancer treatment according to a research report.
Advertisement
 Abrupt Shifts in Disease Linked to Steadily Rising Increases in Mitochondrial DNA MutationsThe way in which subtle changes in mitochondrial function may cause a broad range of common metabolic and degenerative diseases is highlighted. | Advertisement
|
Advertisement
Recommended Reading
Latest Research News
New study findings delineate how aging affects the immune response following Spinal cord injury (SCI) and highlight the participation of the spinal cord meninges in repair.
A recent clinical trial suggests that the first medication therapy to reduce the progression of nearsightedness in children could be on the way.
Autoimmune disorders were found to be linked to Sjogren's, systemic lupus erythematosus, and systemic sclerosis.
Successful brain pacemaker implantation has helped a 51year old Parkinson's disease patient to revitalize her quality of life.
Recent recommendations on lifestyle behaviors to prevent progression of rheumatic and musculoskeletal diseases revealed.