Researchers are discovering it’s possible to determine a person’s age based on the amount of protein in the blood, but the technology isn’t always correct
Mass spectrometry is increasingly finding its way into clinical laboratories and with it—proteomics—the study of proteins in the human body. And like the human genome, scientists are discovering that protein plays an integral part in the aging process.
This is a most interesting research finding. Might medical laboratories someday use proteomic biomarkers to help physicians gauge the aging progression in patients? Might this diagnostic capability give pathologists and laboratory leaders a new product line for direct-to-consumer testing that would be a cash-paying, fast-growing, profitable clinical laboratory testing service? If so, proteomics could be a boon to clinical laboratories worldwide.
When research into genomics was brand-new, virtually no one imagined that someday the direct-to-consumer lab testing model would offer genetic testing to the public and create a huge stream of revenue for clinical laboratories that process genetic tests. Now, research into protein and aging might point to a similar possibility for proteomics.
For example, through proteomics, researchers led by Benoit Lehallier, PhD, Biostatistician, Instructor of Neurology and Neurological Sciences, and senior author Tony Wyss-Coray, PhD, Professor of Neurology and Neurological Sciences and co-director of the Stanford Alzheimer’s Disease Research Center at Stanford University in California, gained an understanding of aging that suggest intriguing possibilities for clinical laboratories.
In their study, published in Nature, titled, “Undulating Changes in Human Plasma Proteome Profiles Across the Lifespan,” the scientists stated that aging doesn’t happen in a consistent process over time, reported Science Alert.
The Stanford researchers also found that they can accurately
determine a person’s age based on the levels of certain proteins in his or her
blood.
Additionally, the study of proteomics may finally explain why blood from young people can have a rejuvenating effect on elderly people’s brains, noted Scientific American.
Each of these findings is important on its own, but taken
together, they may have interesting implications for pathologists who follow
the research. And medical laboratory leaders may find opportunities in mass
spectrometry in the near future, rather than decades from now.
Three Distinct Stages in Aging and Other Findings
The Stanford study found that aging appears to happen at
three distinct points in a person’s life—around the ages 34, 60, and 78—rather
than being a slow, steady process.
The researchers measured and compared levels of nearly 3,000
specific proteins in blood plasma taken from healthy people between the ages of
18 and 95 years. In the published study, the authors wrote, “This new approach
to the study of aging led to the identification of unexpected signatures and
pathways that might offer potential targets for age-related diseases.”
Along with the findings regarding the timeline for aging, the researchers found that about two-thirds of the proteins that change with age differ significantly between men and women. “This supports the idea that men and women age differently and highlights the need to include both sexes in clinical studies for a wide range of diseases,” noted a National Institutes of Health (NIH) report.
“We’ve known for a long time that measuring certain proteins in the blood can give you information about a person’s health status—lipoproteins for cardiovascular health, for example,” stated Wyss-Coray in the NIH report. “But it hasn’t been appreciated that so many different proteins’ levels—roughly a third of all the ones we looked at—change markedly with advancing age.”
Tony Wyss-Coray, PhD (above), Professor of Neurology and Neurological Sciences at Stanford University, was senior author of the proteomics study that analyzed blood plasma from 4,263 people between the ages 18-95. “Proteins are the workhorses of the body’s constituent cells, and when their relative levels undergo substantial changes, it means you’ve changed, too,” he said in a Stanford Medicine news article. “Looking at thousands of them in plasma gives you a snapshot of what’s going on throughout the body.” (Photo copyright: Stanford University.)
Differentiating Aging from Disease
Previous research studies also found it is indeed possible
to measure a person’s age from his or her “proteomic signature.”
The researchers published their findings in Aging Cell, a peer-reviewed open-access journal of the Anatomical Society in the UK, titled, “Plasma Proteomic Signature of Age in Healthy Humans.” In it, the authors wrote, “Our results suggest that there are stereotypical biological changes that occur with aging that are reflected by circulating proteins.”
The fact that chronological age can be determined through a
person’s proteomic signature suggests researchers could separate aging from
various diseases. “Older age is the main risk factor for a myriad of chronic
diseases, and it is invariably associated with progressive loss of function in
multiple physiological systems,” wrote the researchers, adding, “A challenge in
the field is the need to differentiate between aging and diseases.”
Can Proteins Cause Aging?
Additionally, the Stanford study found that changes in protein levels might not simply be a characteristic of aging, but may actually cause it, a Stanford Medicine news article notes.
“Changes in the levels of numerous proteins that migrate
from the body’s tissues into circulating blood not only characterize, but quite
possibly cause, the phenomenon of aging,” Wyss-Coray said.
Can Proteins Accurately Predict Age? Not Always
There were, however, some instances where the protein levels inaccurately predicted a person’s age. Some of the samples the Stanford researchers used were from the LonGenity research study conducted by the Albert Einstein College of Medicine, which investigated “why some people enjoy extremely long life spans, with physical health and brain function far better than expected in the 9th and 10th decades of life,” the study’s website notes.
That study included a group of exceptionally long-lived Ashkenazi Jews, who have a “genetic proclivity toward exceptionally good health in what for most of us is advanced old age,” according to the Stanford Medicine news article.
“We had data on hand-grip strength and cognitive function
for that group of people. Those with stronger hand grips and better measured
cognition were estimated by our plasma-protein clock to be younger than they
actually were,” said Wyss-Coray. So, physical condition is a factor in
proteomics’ ability to accurately prediction age.
Although understanding the connections between protein in
the blood, aging, and disease is in early stages, it is clear additional
research is warranted. Not too long ago the idea of consumers having their DNA
sequenced from a home kit for fun seemed like fantasy.
However, after multiple FDA approvals, and the success of
companies like Ancestry, 23andMe, and the clinical laboratories that serve them,
the possibility that proteomics might go the same route does not seem so
far-fetched.
Microbiome is once again leading scientists toward a new understanding of how human gut bacteria can impact the efficacy and side-effects of certain cancer therapies
Anatomic pathology researchers already know that a person’s genetics can affect the results of cancer treatments. Now it is becoming clear that a patient’s microbiome—which includes gut bacteria—may also impact the efficacy of particular cancer treatments. A recent study showed that gut bacteria can be used to determine whether a cancer drug will work for a certain individual and also if the patient might suffer side effects from certain cancer treatments.
Working with this knowledge, diagnostic test companies may possibly develop new clinical laboratory tests designed to help physicians better diagnose and treat cancer patients. This, in turn, advances personalized medicine and treatments for chronic diseases tailored to patients’ specific physiologies and conditions. This is a healthcare trend where medical laboratories can expect to play a critical role.
Gut Bacteria as Important as Genetics in Cancer Treatments
Libusha Kelly, PhD, Assistant Professor in the Departments of Systems and Computational Biology, and Microbiology and Immunology, led researchers from the Albert Einstein College of Medicine located in Bronx, N.Y., in conducting the study.
“We’ve known for some time that people’s genetic makeup can affect how they respond to a medication,” noted Kelly in an Einstein news release. “Now, it’s becoming clear that variations in one’s gut microbiome—the population of bacteria and other microbes that live in the digestive tract—can also influence the effects of treatment.”
Irinotecan is administered intravenously to colorectal cancer patients in an inactive form and is metabolized to an active form by liver enzymes. The drug is later converted back to an inactive form by other liver enzymes and the addition of a Glucuronidase chemical group. The irinotecan then enters the intestine for expulsion by the body.
Taken from the Einstein College of Medicine published study, the graph above illustrates “Two distinct metabolizer phenotypes or ‘metabotypes’ based on % SN-38 formation during a time course incubation of SN-38G with fecal samples from 20 individuals quantified by LC-MS/MS. Participants were sub-grouped into low (n = 16) and high (n = 4) metabolizer phenotypes. All samples were run in triplicate and values are the mean ± sem.” (Graphic copyright: Nature/Albert Einstein College of Medicine.)
However, bacteria residing in the digestive tract of some individuals prevent the medication from metabolizing properly and reactivates the medication, which transforms the irinotecan into a toxic substance that can cause side effects.
To perform the research, Kelly and her team collected fecal samples from 20 healthy individuals and treated those samples with inactive irinotecan. The samples were then examined and categorized by whether or not they were able to metabolize or reactivate the drug.
Identifying Potential for Side Effects in Patients a Powerful Tool for Medical Laboratories
Irinotecan can cause severe diarrhea and dehydration in up to 40% of patients who take the medication. By focusing on the presence of beta-glucuronidase (enzymes that are used to catalyze the breakdown of complex carbohydrates) the researchers found that gut bacteria can also be used to distinguish which patients will encounter side effects from the drug.
“As you can imagine, such patients are already quite ill, so giving them a treatment that causes intestinal problems can be very dangerous,” said Kelly in the news release. “At the same time, irinotecan is an important weapon against this type of cancer.”
Four of the 20 subjects in the study were determined to be high metabolizers. Due to differences in the composition of their microbiomes, the team concluded that the high metabolizers were more likely to experience side effects from irinotecan.
The research also demonstrated that beta-glucuronidase enzymes in the gut may adversely interact with some commonplace drugs, such as ibuprofen and other nonsteroidal anti-inflammatory medications (NSAIDs), morphine, and Tamoxifen, a drug that is prescribed mainly to breast cancer patients.
“In these cases, the issue for patients may not be diarrhea,” states Kelly in the news release. “Instead, if gut bacteria reactivate those drugs, then patients might be exposed to higher-than-intended doses. Our study provides a broad framework for understanding such drug-microbiome interactions.”
Microbiome Takes Center Stage in Pathology Research
As Dark Daily previously reported, from extending life to developing more powerful treatments for chronic diseases, the human microbiome is quickly becoming an important subject of research studies. The findings from such studies will trigger advances in precision medicine. And, the clinical laboratory assays developed from this research will give physicians the knowledge needed to select the most appropriate drug therapies and treatments for individual patients.
Use of telemedicine services in radiology and pharmacy may hold down labor costs and expand services for patients, but expanded use of telemedicine could also disrupt other local medical subspecialty providers, including pathologists
Over the past 15 years, pathologists have watched how radiology has been disrupted by the “nighthawk” model of remote teleradiology services. Now, the nighthawk approach to telepharmacy could disrupt pharmacy as well. As this happens, pathologists may be wondering when their medical specialty will see its first “nighthawk pathology” disruptors.
Remote Pharmacists Improve Hospital Drug Delivery
One company bringing the nighthawk model to hospital pharmacy services is PipelineRx of San Francisco, California. Its executives believe that they can make the drug delivery system in hospitals more efficient by filling labor shortages with remote pharmacists, according to a MedCity News article.
PipelineRx CEO Brian Roberts acknowledges that his company is taking a page from the teleradiology playbook. “We figured we could do the same with pharmacies because of the technology and create an environment and monitor prescriptions in the hospital and allocate it to home pharmacists,” Roberts told MedCity News, adding that it can both trim costs while ensuring adequate monitoring for patient safety. (more…)
The Center brings together scientists from around the city to translate promising research into medical innovations to treat, prevent and manage disease
Gene sequencing is going big time in the Big Apple. Last month the New York Genome Center (NYGC) moved into a state-of-the-art, 170,000-square-foot genome sequencing and biometrics research building. New York City is putting down its marker to claim a leading role in advancing genetic knowledge.
What makes this development notable for the clinical laboratory industry and the anatomic pathology profession is the fact that cities across the nation are investing substantial amounts of capital to create their own genetic and biotech research and development hubs. Their common objective is to bring together all the expertise, financial support, and business acumen needed to create a job-creating critical mass in the fields of biotech and genetic medicine. (more…)
