New nanosensor technology to detect osteoarthritis biomarker

Researchers at Wake Forest Baptist Medical Center have been able to analyze hyaluronic acid using solid-state nanopore sensor. This technique allows them to study its role in osteoarthritis and other inflammatory joint disorders. This technique is first of a kind and is a significant improvement regarding relative ease to perform and high precision from other techniques like gel electrophoresis, mass spectroscopy or size exclusion chromatography.

The study was led by Hall and Elaheh Rahbar, Ph.D., of Wake Forest Baptist, and conducted in collaboration with scientists at Cornell University and the University of Oklahoma. The study is published in the journal of Nature Communications.

“Our results established a new, quantitative method for the assessment of a significant molecular biomarker that bridges a gap in the conventional technology,” said Adam R. Hall. “The sensitivity, speed and small sample requirements of this approach make it attractive as the basis for a powerful analytic tool with distinct advantages over current assessment technologies.”

In the study researchers first employed synthetic hyaluronic acid polymers to validate the measurement approach. They then used the platform to determine the size distribution of hyaluronic acid extracted from the synovial fluid of a horse model of osteoarthritis.

The measurement approach consists of a microchip with a single hole or pore in it that is a few nanometers wide that is small enough that only individual molecules can pass. And as they do, each can be detected and analyzed. By applying the approach to hyaluronic acid molecules, the researchers were able to determine their size one-by-one. Hyaluronic acid size distribution changes over time in osteoarthritis so this technology could help better assess disease progression, Hall said.

Researchers hope to conduct their next study in humans, and then extend the technology with other diseases where hyaluronic acid and similar molecules play a role, including traumatic injuries and cancer.

Citation: Rivas, Felipe, Osama K. Zahid, Heidi L. Reesink, Bridgette T. Peal, Alan J. Nixon, Paul L. Deangelis, Aleksander Skardal, Elaheh Rahbar, and Adam R. Hall. “Label-free analysis of physiological hyaluronan size distribution with a solid-state nanopore sensor.” Nature Communications 9, no. 1 (2018). doi:10.1038/s41467-018-03439-x.

Adapted from press release by Wake Forest Baptist Medical Center.

Research shows key role of FoxO proteins in osteoarthritis development

Research from scientists at The Scripps Research Institute explains why the risk of osteoarthritis increases as we age and offers a potential avenue for developing new treatments. The study’s findings suggest that FOXO proteins are responsible for the maintenance of healthy cells in the cartilage of our joints. The results are published in journal Science Translational Medicine.

“We discovered that FoxO transcription factors control the expression of genes that are essential for maintaining joint health,” says Martin Lotz, MD, a TSRI professor and senior author of the study. “Drugs that boost the expression and activity of FoxO could be a strategy for preventing and treating osteoarthritis.”

Previous research from Lotz’ lab showed that as joints age, levels of FoxO proteins in cartilage decrease. Lotz and his colleagues had also found that people with osteoarthritis have a lower expression of the genes needed for a process called autophagy. Autophagy is a cell’s way of removing and recycling its own damaged structures to stay healthy.

For the new study, researchers used mouse models with FoxO deficiency in cartilage to see how the FoxO proteins affect maintenance of cartilage throughout adulthood. The researchers noticed a striking difference in the mice with “knockout” FoxO deficiency. Their cartilage degenerated at much younger age than in control mice. The FoxO-deficient mice also had more severe forms of post-traumatic osteoarthritis induced by meniscus damage (an injury to the knee), and these mice were more vulnerable to cartilage damage during treadmill running.

The FoxO-deficient mice had defects in autophagy and in mechanisms that protect cells from damage by molecules called oxidants. Specific to cartilage, FoxO-deficient mice did not produce enough lubricin, a lubricating protein that normally protects the cartilage from friction and wear. This lack of lubricin was associated with a loss of healthy cells in a cartilage layer of the knee joint called the superficial zone.

These problems all came down to how FoxO proteins work as transcription factors to regulate gene expression. Without FoxO proteins running the show, expression of inflammation-related genes skyrockets, causing pain, while levels of autophagy-related genes plummet, leaving cells without a way to repair themselves. “The housekeeping mechanisms, which keeps cells healthy, were not working in these knockout mice,” Lotz explains.

To determine whether targeting FoxO has therapeutic benefits, the investigators used genetic approaches to increase FoxO expression in cells of humans with osteoarthritis and found that the levels of lubricin and protective genes returned to normal. The next step in this research is to develop molecules that enhance FoxO and test them in experimental models of osteoarthritis.

Citation: Matsuzaki, Tokio, Oscar Alvarez-Garcia, Sho Mokuda, Keita Nagira, Merissa Olmer, Ramya Gamini, Kohei Miyata, Yukio Akasaki, Andrew I. Su, Hiroshi Asahara, and Martin K. Lotz. “FoxO transcription factors modulate autophagy and proteoglycan 4 in cartilage homeostasis and osteoarthritis.” Science Translational Medicine 10, no. 428 (2018). doi:10.1126/scitranslmed.aan0746.

Research funding: NIH

Adapted from press release by The Scripps Research Institute.

Delaying aging process by selective removal of senescent cells

A recent study, led by an international team of researchers confirms that targeted removal of senescent cells (SnCs), accumulated in many vertebrate tissues as we age, contribute significantly in delaying the onset of age-related pathologies.

Credit: Baker et al., Nature 

This breakthrough research has been led by Dr. Chaekyu Kim and Dr. Ok Hee Jeon. In the study, the research team presented a novel pharmacologic candidate that alleviates age-related degenerative joint conditions, such as osteoarthritis (OA) by selectively destroying SnCs. Their findings, published in Nature Medicine, suggest that the selective removal of old cells from joints could reduce the development of post-traumatic OA and allow new cartilage to grow and repair joints.

To test the idea that SnCs might play a causative role in OA, the research team took both younger and older mice and cut their anterior cruciate ligaments (ACL) to minic injury. They, then, administered injections of an experimental drug, named UBX0101 to selectively remove SnCs after anterior cruciate ligament transection (ACLT) surgery.

Preclinical studies in mice and human cells suggested that the removal of SnCs significantly reduced the development of post-traumatic OA and related pain and created a prochondrogenic environment for new cartilage to grow and repair joints. Indeed, the research team reported that aged mice did not exhibit signs of cartilage regeneration after treatment with UBX0101 injections,

According to the research team, the relevance of their findings to human disease was validated using chondrocytes isolated from arthritic patients. The research team notes that their findings provide new insights into therapies targeting SnCs for the treatment of trauma and age-related degenerative joint disease.

Citation: Jeon, Ok Hee, Chaekyu Kim, Remi-Martin Laberge, Marco Demaria, Sona Rathod, Alain P. Vasserot, Jae Wook Chung, Do Hun Kim, Yan Poon, Nathaniel David, Darren J. Baker, Jan M Van Deursen, Judith Campisi, and Jennifer H. Elisseeff. “Local clearance of senescent cells attenuates the development of post-traumatic osteoarthritis and creates a pro-regenerative environment.” Nature Medicine 23, no. 6 (2017): 775-81.
doi:10.1038/nm.4324.
Adapted from press release by the Uslan National Institute of Science and Technology.

Review of literature shows that Acupuncture improves medical treatment for depression and chronic pain

Health specialists at the University of York have found that acupuncture treatment can boost the effectiveness of standard medical care, lessening the severity of chronic pain and depression.

In a report published in the National Institute for Health Research (NIHR) Journals Library, the researchers showed that there is significant evidence to demonstrate that acupuncture provides more than a placebo effect.

Professor of Acupuncture Research, Hugh MacPherson, working with a team of scientists from the UK and US, brought together the results of 29 high-quality clinical trials focused on patients treated with acupuncture and standard medical care.

In the majority of these trials, patients with chronic pain treated with acupuncture and standard medical care were tested against those who were provided with standard medical care alone, such as anti-inflammatory drugs and physiotherapy. The trials involved approximately 18,000 patients diagnosed with chronic pain of the neck, lower back, head, and knee.

The report shows that the addition of acupuncture compared to standard medical care alone significantly reduced the number of headaches and migraine attacks and reduced the severity of neck and lower back pain. It also showed that acupuncture reduced the pain and disability of osteoarthritis, which led to patients being less reliant on anti-inflammatory tablets to control pain.

The study also concluded that acupuncture is cost-effective, with the value for money being rated as less than the threshold of £20,000 cost per quality of life year – a metric for cost-effectiveness used by the National Institute for Health and Care Excellence (NICE).

Professor MacPherson, from the University of York’s Department of Health Sciences, said: “There has been an increase in practitioners using acupuncture as an intervention. Approximately four million acupuncture treatments are provided a year in the UK, but the evidence to show how clinically effective this form of treatment is has been limited.

“There has been a question mark for many years over whether policy and decision makers should or should not provide wider access to acupuncture. Our aim was to bring together data from high-quality clinical trials and provide a robust evidence base that will help reduce this uncertainty and support commissioners and health professionals in making informed decisions backed up with research.”

The team also conducted a new clinical trial for depression, where acupuncture or counseling was provided and compared to the effectiveness of medication, such as antidepressants.

In a study of 755 patients with depression in the North of England, researchers showed that both acupuncture and counseling significantly reduced the severity of depressions and that these benefits were largely sustained for up to 12 months after treatment.

Professor MacPherson said: “The front-line treatment for depression in primary care usually involves antidepressants; however, they do not work well for more than half of patients.

“In the largest study of its kind, we have now provided a solid evidence base to show that not only can acupuncture and counseling bring patients out of an episode of depression, but it can keep the condition at bay for up to a year on average.”

The benefits of acupuncture are partially associated with placebo effects, which has contributed to the uncertainty around acupuncture’s clinical effectiveness. Professor MacPherson states, however, that this new research provides definitive evidence that when acupuncture is used to treat chronic pain, the reductions in pain are substantially more than those measured from sham (placebo) acupuncture.

Used only in clinical trials for research purposes, sham acupuncture involves inserting needles at the ‘wrong’ locations or using non-inserted needles (fake needles) at the correct locations. That ‘true’ acupuncture has significantly more effect in reducing pain than sham acupuncture, provides evidence that acupuncture is not simply a placebo effect.

Professor MacPherson added: “Our new data provides a significant step forward in treating chronic pain and managing depression because patients and health professionals can now make decisions on acupuncture with more confidence. Not only is it more cost effective, but it reduces pain levels and improves mood levels, which could reduce over-reliance on drugs that can sometimes result in unwanted side effects.”

Citation: MacPherson H, Vickers A, Bland M, Torgerson D, Corbett M, Spackman E, et al. Acupuncture for chronic pain and depression in primary care: a programme of research. Programme Grants Appl Res 2017;5(3)
DOI: 10.3310/pgfar05030
Adapted from press release by University of York.

Researchers develop blood test to diagnose early osteoathritis

Led by Dr Naila Rabbani of Warwick Medical School, the researchers developed a test that can provide an early diagnosis of osteoarthritis (OA) and also distinguish this from early-stage rheumatoid arthritis (RA) and other self-resolving inflammatory joint disease. The test, which could be available to patients within two years, identifies the chemical signatures found in the plasma of blood joint proteins damaged by oxidation, nitration and glycation; the modification of proteins with oxygen, nitrogen and sugar molecules.

The researchers say that by diagnosing which type of arthritis a patient will develop at an early-stage will allow for appropriate treatment that will provide the best chance for effective treatment and potential prevention.

Patients with early-stage and advanced OA, RA or other inflammatory joint disease were recruited for the study alongside a control group of those with good skeletal health, with plasma and synovial fluid samples from both groups being analysed using mass spectrometry. Through their analysis the researchers detected damaged proteins in characteristic patterns in the samples of those patients with early and advanced OA and RA, but were found at markedly lower levels in the samples of those in the control group – providing the researchers with the identifiable biomarkers necessary for early detection and diagnosis.

Commenting on the discovery Dr Rabbani said: “Damage to proteins in the arthritic joint have been known for many years but this is the first time it has been exploited for early-stage diagnosis. For the first time we measured small fragments from damaged proteins that leak from the joint into blood. The combination of changes in oxidised, nitrated and sugar-modified amino acids in blood enabled early stage detection and classification of arthritis – osteoarthritis, rheumatoid arthritis or other self-resolving inflammatory joint disease. This is a big step forward for early-stage detection of arthritis that will help start treatment early and prevent painful and debilitating disease.”

Citation:
Ahmed, Usman, Attia Anwar, Richard S. Savage, Paul J. Thornalley, and Naila Rabbani. “Protein oxidation, nitration and glycation biomarkers for early-stage diagnosis of osteoarthritis of the knee and typing and progression of arthritic disease.” Arthritis Research & Therapy 18, no. 1 (2016): 250.
DOI: http://dx.doi.org/10.1186/s13075-016-1154-3
Adapted from press release by Warwick Medical School

Nanoparticle injections minimize inflammation following cartilage injury

Osteoarthritis is a debilitating condition that affects at least 27 million people in the United States, and at least 12 percent of osteoarthritis cases stem from earlier injuries. Over-the-counter painkillers, such as anti-inflammatory drugs, help reduce pain but do not stop unrelenting cartilage destruction. Consequently, pain related to the condition only gets worse.

Now, researchers at Washington University School of Medicine in St. Louis have shown in mice that they can inject nanoparticles into an injured joint and suppress inflammation immediately following an injury, reducing the destruction of cartilage.

The findings are reported online Sept. 26 in the early edition of the Proceedings of the National Academy of Sciences.

In this study, the nanoparticles were injected shortly after an injury, and within 24 hours, the nanoparticles were at work taming inflammation in the joint. But unlike steroid injections that are quickly cleared, the particles remained in cartilage cells in the joints for weeks.

The nanoparticles used in the study are more than 10 times smaller than a red blood cell, which helps them penetrate deeply into tissues. The particles carry a peptide derived from a natural protein called melittin that has been modified to enable it to bind to a molecule called small interfering RNA (siRNA). The melittin delivers siRNA to the damaged joint, interfering with inflammation in cells.
The peptide-based nanoparticle was designed by study co-investigators Hua Pan, PhD, an assistant professor of medicine, and Samuel Wickline, MD, the James R. Hornsby Family Professor of Biomedical Sciences.

“The nanoparticles are injected directly into the joint, and due to their size, they easily penetrate into the cartilage to enter the injured cells,” Wickline said. “Previously, we’ve delivered nanoparticles through the bloodstream and shown that they inhibit inflammation in a model of rheumatoid arthritis. In this study, they were injected locally into the joint and given a chance to penetrate into the injured cartilage.”

The nanoparticles were injected shortly after injury to prevent the cartilage breakdown that eventually leads to osteoarthritis. Whether such a strategy will work years after an injury, when osteoarthritis is established and there is severe cartilage loss, still needs to be studied.  But the findings suggest that the nanoparticles, if given soon after joint injuries occur, could help maintain cartilage viability and prevent the progression to osteoarthritis.

Publication: Suppression of NF-κB activity via nanoparticle-based siRNA delivery alters early cartilage responses to injury.
doi: 10.1073/pnas.1608245113                        
Press release by Washington University School of Medicine