Daily finger-prick blood tests are an uncomfortable fact of life for diabetics, but they may not always have to be. Scientists from Canada and the US have now developed a prototype home-use device that measures blood glucose levels via saliva samples.
It was already known that concentrations of glucose (and certain other biomarker chemicals) in a person's saliva are proportional to those in their bloodstream. Because glucose levels are much lower in saliva, however, specialized lab-based equipment is required to accurately measure them.
Researchers from the Université de Sherbrooke in Quebec and the Colgate-Palmolive Company in New Jersey set out to change that, by looking to an existing tool known as an electrochemical aptamer-based (E-AB) biosensor.
Such devices incorporate a specially engineered piece of DNA – called an aptamer – that binds to a target biomarker in a sample. When that happens, the sensor produces a measurable electrochemical signal.
Researchers at St Vincent's Institute of Medical Research (SVI) in Melbourne have shown that a commonly prescribed rheumatoid arthritis drug can suppress the progression of type 1 diabetes.
The world-first human trial, published in the New England Journal of Medicine and led by SVI's Professor Thomas Kay, showed that a drug called baricitinib can safely and effectively preserve the body's own insulin production and suppress the progression of type 1 diabetes in people who initiated treatment within 100 days of diagnosis.
"When type 1 diabetes is first diagnosed there is a substantial number of insulin-producing cells still present. We wanted to see whether we could protect further destruction of these cells by the immune system. We showed that baricitinib is safe and effective at slowing the progression of type 1 diabetes in people who have been recently diagnosed," said Professor Kay.
Researchers at Case Western Reserve University and University Hospitals have identified an enzyme that blocks insulin produced in the body—a discovery that could provide a new target to treat diabetes.
Their study, published Dec. 5 in the journal Cell, focuses on nitric oxide, a compound that dilates blood vessels, improves memory, fights infection and stimulates the release of hormones, among other functions. How nitric oxide performs these activities had long been a mystery.
The researchers discovered a novel "carrier" enzyme (called SNO-CoA-assisted nitrosylase, or SCAN) that attaches nitric oxide to proteins, including the receptor for insulin action.
They found that the SCAN enzyme was essential for normal insulin action, but also discovered heightened SCAN activity in diabetic patients and mice with diabetes. Mouse models without the SCAN enzyme appeared to be shielded from diabetes, suggesting that too much nitric oxide on proteins may be a cause of such diseases.
Changes in small blood vessels are a common consequence of diabetes development. Researchers at the Technical University of Munich (TUM) and Helmholtz Munich have now developed a method that can be used to measure these microvascular changes in the skin—and thus assess the severity of the disease. To achieve this, they combine artificial intelligence (AI) and innovative high-resolution optoacoustic imaging technology. The work is published in the journal Nature Biomedical Engineering.
Optoacoustic imaging methods use light pulses to generate ultrasound inside tissue. The ultrasound waves generated are then recorded by sensors and converted to images. The signals are caused by tiny expansions and contractions of tissue that surround molecules that strongly absorb light. One such molecule is hemoglobin. Since hemoglobin is concentrated in blood vessels, optoacoustic imaging can produce detailed unique images of vessels in ways not possible by other non-invasive techniques.
The basic principles of optoacoustics, or photoacoustics, have been known for more than a century, but practical applications in medicine are fairly recent. Vasilis Ntziachristos is Professor of Biological Imaging at TUM and Director of the Institute of Biological and Medical Imaging and of the Bioengineering Center at Helmholtz Munich. Together with his team, he has developed a range of optoacoustic imaging methods, among them RSOM, short for raster-scan optoacoustic mesoscopy.
Scientists discover new "cause" for diabetes, opening new treatments
By Michael Irving
December 11, 2023
Scientists have discovered a new mechanism for how type 2 diabetes takes hold, and demonstrated in mice that blocking a particular enzyme could open a new avenue of treatment for the disease.
Type 2 diabetes begins as a patient’s body stops responding to insulin, and eventually loses the ability to produce enough of the hormone. Without it, blood glucose levels remain high and can cause a range of serious health problems. But scientists still don’t fully understand exactly why the insulin system stops working in the first place.
In the new study, scientists at Case Western Reserve University and University Hospitals have identified an enzyme that plays an important role. Known as SCAN, the enzyme is a carrier that attaches nitric oxide to proteins, including one that acts as a receptor for insulin action.
Nitric oxide is a key chemical messenger in the body, which aids circulation and regulates hormones, including insulin. But the team detected heightened SCAN activity in both mice and humans with diabetes, and inversely, engineered mice that lacked the SCAN enzyme seemed to be protected from the effects of diabetes.
Healthy Plant-based Diet reduces Diabetes Risk by 24 Per Cent December 11, 2023
Introduction:
(Eurekalert) At least 75 per cent of type 2 diabetes cases could be avoided by adopting a healthy lifestyle. A plant-based diet has been shown to play a key role in this. With limitations - as demonstrated in a study led by Tilman Kühn from MedUni Vienna's Center for Public Health: A more plant-based diet only develops its protective effects if not only the consumption of animal-based foods, but also industrially processed and highly sugary foods is reduced. For the first time, the scientists identified improvements in metabolism and liver and kidney function as reasons for the positive effects of a healthy plant-based diet, in addition to the associated lower likelihood of obesity. The study results were recently published in the journal Diabetes & Metabolism.
According to analyses by the research team, a healthy plant-based diet with plenty of fresh fruit and vegetables and wholemeal products reduces the risk of diabetes by 24 per cent, even in the presence of a genetic predisposition and other diabetes risk factors such as obesity, advanced age or a lack of physical activity. Unhealthy plant-based diets with a high proportion of sweets, refined grains and sugary drinks, on the other hand, are associated with an increased risk of type 2 diabetes.
Key biomarkers identified
The research was carried out with 113,097 participants in the large-scale British cohort study (UK Biobank) over an observation period of twelve years. According to their findings, the reasons behind the anti-diabetic effect of a healthy plant-based diet go far beyond the well-known lower body fat percentage and waist circumference. "Our study is the first to identify biomarkers of central metabolic processes and organ functions as mediators of the health effects of a plant-based diet," says Tilman Kühn, Professor of Public Health Nutrition at MedUni Vienna and the University of Vienna, who led the study in close collaboration with researchers from Queen's University Belfast. The investigations confirmed that normal values for blood lipids (triglycerides), blood sugar (HbA1c), inflammatory parameters (CRP) and the insulin-like growth factor (IGF1) are associated with a low risk of diabetes.
A Rutgers professor and other researchers have performed a systematic review and meta-analysis to evaluate studies comparing perinatal outcomes among individuals with gestational diabetes mellitus. Pregnancy weight and biochemical markers measured in blood from women with gestational diabetes mellitus (GDM) were related to increased risk of poor pregnancy outcomes, suggesting a new direction for precision diagnostics, according to researchers.
The study led by Ellen C. Francis, an assistant professor in the Department of Biostatistics and Epidemiology at Rutgers School of Public Health, and published in Communications Medicine, evaluated the diagnostic value of these markers before or at the time of screening for GDM, a type of diabetes that can develop during pregnancy.
Research led by the Massachusetts Institute of Technology Sloan School of Management, Cambridge, has found that an intensive food-as-medicine program showed no improvement in glycemic control in patients with type 2 diabetes and food insecurity.
In their paper, "Effect of an Intensive Food-as-Medicine Program on Health and Health Care Use—A Randomized Clinical Trial," published in JAMA Internal Medicine, the team details a randomized clinical trial of 349 type 2 diabetes patients with previous food insecurity to assess if short-term access to healthy food options could improve glycemic control and influence health care usage. An Editor's Note by Deborah Grady on the study was published in the same journal issue.
The study targeted patients with type 2 diabetes and elevated HbA1c levels, providing intensive support and food supplies. Subjects in the treatment group (n=170) were given groceries for 10 healthy meals per week for the household, dietitian consultations, nurse evaluations, health coaching, and diabetes education for one year with a one-year follow-up. A control group (n=179) did not receive any of the benefits of the treatment program for the first six months.
Hemoglobin A1C (HbA1c) tests six months into the program showed substantial declines in both the treatment (1.5%) and control (1.3%) groups, resulting in no significant difference between groups. This might indicate that factors beyond the program contributed to the lower blood sugar levels, though what these factors might be is unclear.
A team of chemists, polymer scientists and drug delivery specialists at Zhejiang University, working with a pair of colleagues from the University of North Carolina at Chapel Hill, has developed a type of "smart" insulin that when tested in mouse and minipig models successfully regulated blood glucose levels for up to one week after just one injection.
In their paper published in the journal Nature Biomedical Engineering, the group describes how they created their insulin, how it works, and how well it performed when given to diabetic mice and minipigs.
Diabetes type I is a chronic condition in which the pancreas produces little or no insulin. Treatment for people with the disease includes a modified diet and regular injections of insulin. Many diabetics have to inject themselves more than once a day, a regimen that is both painful and difficult—the skin at injection sites tends to harden over time, making it difficult to insert a needle.
Because of such difficulties, medical researchers have continued to look for new treatment options. In this new effort, the research team has developed a kind of insulin that reacts with certain agents in the body, allowing for automatic control of glucose levels in the blood for an extended period of time.
The new smart insulin is a modified form of the type of insulin already in use—the researchers added gluconic acid, which when injected into the body transforms into a complex as it bonds with chemicals in the blood. Such complexes result in the insulin being trapped inside a natural polymer, and that results in alterations to signaling. Different amounts of insulin are released depending on blood glucose levels. This, the research team found, allowed for more insulin to be automatically released into the blood when it is needed (such as after a meal) and less when it is not.
The researchers tested their modified insulin on three minipigs and five mice—all of which had been engineered to have diabetes. Two of the minipigs received a high dose, while the third received a low dose.
