Tag: 15/3/23

Autism in Children Linked to Diabetes, Dyslipidaemia

Photo by Peter Burdon on Unsplash

Studies have shown that children with autism spectrum disorder (ASD) have an increased risk of obesity. In turn, obesity has been linked to increased risks for diabetes, dyslipidaemia and other cardiometabolic disorders. However, the question of whether or not there is an association between autism, cardiometabolic disorders and obesity remains largely unanswered.

To help provide an insight into the possible link between ASD and cardiometabolic diseases, Texas Tech University researchers conducted a systematic review and meta-analysis. Their findings were published in JAMA Pediatrics.

In this latest meta-analysis, the researchers evaluated 34 studies that included 276 173 participants who were diagnosed with ASD and 7 733 306 who were not. The results indicated that ASD was associated with greater risks of developing diabetes overall, including both type 1 and type 2 diabetes.

The meta-analysis also determined that autism is associated with increased risks of dyslipidaemia and heart disease, though there was no significant increased risk of hypertension and stroke associated with autism. However, meta-regression analyses revealed that children with autism were at a greater associated risk of developing diabetes and hypertension when compared with adults.

Study leader Chanaka N. Kahathuduwa, MD, PhD, said the overall results demonstrate the associated increased risk of cardiometabolic diseases in ASD patients, which should prompt clinicians to more closely monitor these patients for potential contributors, including signs of cardiometabolic disease and their complications.

“We have established the associations between autism and obesity, as well as autism and cardiometabolic disease, including diabetes and dyslipidaemia,” Kahathuduwa said. “We don’t have data to support a conclusion that autism is causing these metabolic derangements, but since we know that a child with autism is more likely to develop these metabolic complications and derangements down the road, I believe physicians should evaluate children with autism more vigilantly and maybe start screening them earlier than the usual.”

Kahathuduwa also believes the study shows that physicians should think twice before prescribing medications such as olanzapine that are well known to have metabolic adverse effects to children with autism.

“Our findings should also be an eye opener for patients with autism and parents of kids with autism to simply be mindful about the higher risk of developing obesity and metabolic complications,” Kahathuduwa added. “Then they can talk with their physicians about strategies to prevent obesity and metabolic disease.”

Kahathuduwa said the next logical step for the collaborative team would be to generate evidence that either supports or rejects causality with regard to the observed associations.

Source: Texas Tech University Health Sciences Center

Medical Students Retain Knowledge Better from Virtual Reality Lessons

A trial published in the International Journal of Gynecology & Obstetrics lends support to the idea that 3D virtual reality lessons can improve medical students’ retention of knowledge and understanding of complex topics in obstetrics and gynaecology.

For the study, 21 students took part in a 15-minute virtual reality learning environment (VRLE) experience on the stages of foetal development, while 20 students received a PowerPoint tutorial on the same topic, serving as a control.

While the students’ level of knowledge increased after both learning experiences, it was only retained in the VRLE group at one-week follow up. Questionnaires completed by participants reflected a high degree of satisfaction with the VRLE tool compared with the traditional tutorial.

“Virtual reality learning tools hold potential to enhance student learning and are very well received by students,” said corresponding author Fionnuala McAuliffe, MD, of University College Dublin National Maternity Hospital, in Ireland.

Source: Wiley

Common Cold may Have Conferred COVID Immunity to Children

Young girl sneezing
Photo by Andrea Piacquadio on Unsplash

Early in the COVID pandemic, it became clear that children infected with the coronavirus rarely developed serious disease. One hypothesis has been that children already have some immunity provided by memory T cells generated by common colds. Researchers at Karolinska Institutet are now able to show that OC43, one of the coronaviruses that cause common colds, boosts the immune response to COVID. The study, which is published in PNAS, could give rise to more tailored vaccine programmes for children and adults.

After studying unique blood samples from children taken before the pandemic, Karolinska Institutet researchers have now identified memory T cells that react to cells infected with SARS-CoV-2.

This new study reinforces this hypothesis and shows that T cells previously activated by the OC43 virus can cross-react against SARS-CoV-2.

Four coronaviruses cause common colds

One of the four coronaviruses causing seasonal common cold symptoms could stimulate an immune response with T cells able to also react to cells infected with SARS-CoV-2.

“These reactions are especially strong early in life and grow much weaker as we get older,” says the study’s corresponding author Annika Karlsson, research group leader at the Department of Laboratory Medicine, Karolinska Institutet. “Our findings show how the T-cell response develops and changes over time and can guide the future monitoring and development of vaccines.”

Strong immunity at the age of two

The results indicate that the memory T-cell response to coronaviruses develops as early as the age of two. The study was based on 48 blood samples from two- and six-year-old children, and 94 samples from adults between the ages of 26 and 83. The analysis also included blood samples from 58 people who had recently recovered from COVID-19.

“Next, we’d like to do analogous studies of younger and older children, teenagers and young adults to better track how the immune response to coronaviruses develops from childhood to adulthood,” says Marion Humbert, postdoctoral researcher currently at the Department of Medicine Huddinge, Karolinska Institutet, joint first author with Anna Olofsson, doctoral student at the Department of Laboratory Medicine.

Source: Karolinska Institutet

In Wounds, Fibroblasts also Clear Away Damaged Tissue

Photo by Diana Polekhina on Unsplash

Burn wounds are notoriously prone to bacterial infection and typically lead to a larger amount of scar tissue than laceration wounds, but new research shows that fibroblasts – normally considered as construction cells – clear away damaged tissue before depositing new material. The more damaged tissue there is, the longer it takes for the fibroblasts to remove the material and heal.

In APL Bioengineering, researchers from Boston University and Harvard University describe how they created a biomimetic model to study wound healing in burn and laceration wounds, which is slower in burn wound as more tissue damage is present.

Cell biologists identify four phases of wound healing: bleeding stoppage, inflammation, new tissue formation, and tissue strengthening. During the inflammation and formation stages, immune cells are thought to clear bacteria and dead cells from the wound. They also activate fibroblasts and blood vessels to begin repairs.

“Depending on the injury, the extent and duration of these four phases can wildly vary across different wound types,” said author Jeroen Eyckmans. “Given that laceration wounds are well perfused with blood, they tend to heal well. However, in burns, the blood vessels are cauterised, preventing blood from entering the wound bed and slowing down the healing process. Severe burn wounds also have large amounts of dead tissue that physically block new tissue formation.”

To study how the mode of injury impacts the healing rate of wounds, the team designed an in vitro model system made of fibroblasts embedded in a collagen hydrogel. Wounds were created in this microtissue using a microdissection knife to mimic laceration or a high-energy laser to simulate a burn.

Although both wound types were equal in size, laser ablation caused more cell death and tissue damage next to the wound margins compared to knife wounds.

“During healing, we found that the fibroblasts first cleared the damaged material from the wound before depositing new material,” said Eyckmans. “This was a surprising finding because removal of dead tissue has been attributed to specialised immune cells such as macrophages, and fibroblasts have been considered to be tissue-building cells, not tissue-removal cells.”

Given that there was more tissue damage in the laser ablation wounds, it took fibroblasts more time to remove the damage, ultimately delaying tissue healing.

Based on these findings, therapies that promote wound clearance could accelerate healing. Genetically engineered white blood cells, designed to remove dead tissue, could be particularly useful for reaching injured organs and tissues deep in the body.

Source: American Institute of Physics

Hunger Hormone Increases Cardiac Function in Heart Failure

Source: Pixabay CC0

A clinical study published in the European Heart Journal shows that the hunger hormone ghrelin can increase the heart’s pump capacity in patients with heart failure.

Heart failure occurs when the heart muscles are weakened, such as from myocardial infarction, reducing the ability to pump blood. Current treatments can slow disease progression, but none directly increase the heart’s pumping capacity.

Ghrelin is an endogenous hormone that has many receptors distributed in cardiac muscle tissues. It increases the appetite and stimulates the release of growth hormones. The researchers believe that its receptors are a promising target for enhancing the heart’s pumping capacity.

“Heart failure is the most common cause of hospitalisation in older generations and is associated with a poor quality of life and high mortality,” says principal investigator Lars Lund, professor at the Department of Medicine, Solna, Karolinska Institutet, and senior consultant at Karolinska University Hospital. “If we can find ways to increase the heart’s pump function, we can potentially improve life quality and prognosis for these patients.”

In this double-blind study, 30 patients with heart failure at Karolinska University Hospital’s cardiology unit were randomly assigned to two groups, receiving either active treatment with ghrelin or a placebo given intravenously for two hours. The participants were followed up after two to five days.

Pump function up by 28%

After two hours’ treatment, the cardiac output had increased by an average of 28% in the ghrelin group, (4.08 ± 1.15 to 5.23 ± 1.98 L/min) compared to a small reduction in the placebo group (4.26 ± 1.23 to 4.11 ± 1.99 L/min). The increase was from more blood being pumped per beat, as the heart rate remained unchanged or was even slightly slower. At the two- to five-day follow-up, the pump capacity was still 10% higher in the ghrelin group compared to in the placebo group.

No serious adverse reactions were seen, though the ghrelin group had slightly elevated levels of a heart-failure biomarker, which would need to be investigated further. The small size of the group makes limits the generalisability of the results.

Using mouse heart cells, the researchers observed that treatment with ghrelin increased the contractile function of the heart cells, and they identified a novel molecular mechanism for this increase. The researchers now plan to do larger clinical studies.

Source: Karolinska Institutet