Day: May 10, 2021

Categories : Ageing Diet and Nutrition Neurodegenerative DiseasesTags :

A Mediterranean Diet Keeps Dementia at Bay

On By ModernMedia
A dish full of vegetables which could be in a Mediterranean diet.

Researchers have reported that a Mediterranean diet may reduce the risk of developing dementia and cognitive loss, helping preserve memory functions as people age.

Specifically, the diet appears to lower the level of amyloid and tau proteins that are linked with dementia. People following the Mediterranean diet, already noted for its numerous health benefits, scored better on memory tests than those who were not following the diet.

The first of these proteins, amyloid protein, forms plaques in the brain, whereas the second, tau protein, forms tangles. Both are present in the brains of people with Alzheimer’s, though they are not uncommon in the brains of healthy older people, too.

“These results add to the body of evidence that shows what you eat may influence your memory skills later on,” said study author Tommaso Ballarini, PhD, of the German Center for Neurodegenerative Diseases in Bonn, Germany. He adds:

Studies have linked good health with the foods that people living in Greece, Spain, and Italy ate before the 1960s. This diet consists primarily of vegetables and fruits, nuts and seeds, legumes, potatoes, whole grain foods, seafood, extra virgin olive oil, and wine in moderation. Poultry, eggs and dairy products are present to a limited extent, while red meat, added sugar, refined grains and oils, and processed foods are typically lacking in a Mediterranean diet.

Kristin Kirkpatrick, a dietitian at Cleveland Clinic told Medical News Today that the contents of a Mediterranean diet offers beneficial “omega-3 fatty acids, polyphenols, specific minerals, fiber, and protein” that “may support the brain’s health and protection throughout the years.”

However, Kirkpatrick cautioned that, “A diet, even one with strong clinical data on its benefit, is only as healthy as the individuals who choose its structure.”

Sensible portion sizes are important, she noted and warned against the “consumption of processed foods that are marketed as heart-healthy or contain the components seen in a traditional Mediterranean approach.”

The investigators recruited 512 individuals from the German Centre for Neurodegenerative Diseases’ Longitudinal Cognitive Impairment and Dementia StudyTrusted Source. Participant  assessments showed that 343 were at a higher risk of developing Alzheimer’s disease while the other 169 people were “cognitively normal.”

Participants filled in questionnaires regarding the food they ate the previous month and the investigators asked them to record their intake of 148 specific food items. Participants were scored on their diet’s similarity to a Mediterranean diet, the most similar receiving a 9 and the least similar a 1. Since this was a self-reported study on eating habits, errors or misrepresentations are possible.

Individuals also took cognitive tests designed to detect the progression of Alzheimer’s disease. The tests assessed five areas: memory, working memory, language, executive functions, and visuospatial abilities. MRI brain scans determined each individual’s brain volume.

Finally, the researchers analyzed spinal fluid from a subsample of 226 participants who gave their consent, assessing the presence and amounts of the two biomarker proteins: amyloid and tau.

After adjusting for sex, age, and education, the scientists identified several clear links between better cognitive health and a Mediterranean diet.

The investigators  reported that:

  • Every dietary score point lower than 9 was linked to almost 1 year of the brain ageing that occurs in Alzheimer’s disease progression.
  • Participants who most closely followed the Mediterranean diet had fewer amyloid and tau protein biomarkers in their spinal fluid than those who had lower dietary scores.
  • People on the Mediterranean diet scored better on memory tests than people who were not.

Dr Ballarani concluded that, “More research is needed to show the mechanism by which a Mediterranean diet protects the brain from protein buildup and loss of brain function, but findings suggest that people may reduce their risk for developing Alzheimer’s by incorporating more elements of the Mediterranean diet into their daily diets.”

Source: Medical News Today

Categories : COVID Gender GeneticsTags :

Severe COVID and Male Balding Gene Linked

On By ModernMedia
Photo by Brett Sayles from Pexels

While COVID has been long known to be more dangerous in men than women, research which is still in its early stages shows that some of this increased risk could be from having a gene for male balding. 

A team of researchers in the US first suspected the link when they noticed that men with a common form of hormone-sensitive hair loss, known as androgenetic alopecia, were also more likely to be hospitalised with COVID.  They presented their findings May 6 at the virtual spring meeting of the European Academy of Dermatology and Venereology (EADV).

“Among hospitalized men with COVID-19, 79% presented with androgenetic alopecia compared to 31%-53% that would be expected in a similar aged match population,” said researchers led by Dr Andy Goren, chief medical officer at Applied Biology Inc in California. 

The researchers noted that androgenetic alopecia is due to the activity of the androgen receptor (AR) gene, which can lead to balding in some men. An enzyme called TMPRSS2, key to COVID infection, is also androgen-sensitive, and might be affected by the AR gene as well, explained Dr Goren’s group.

One key segment on the AR gene seems to affect both COVID severity and male balding.

In the new study, the Irvine group enrolled 65 men hospitalised with COVID, and conducted a genetic analysis on them. The results showed that participants with certain structural differences in the AR gene were at greater risk of developing severe COVID. Speaking in a meeting press release, Goren said the AR gene anomaly “could be used as a biomarker to help identify male COVID-19 patients most at risk for ICU admissions.”

He added that he believes that “the identification of a biomarker connected with the androgen receptor is another piece of evidence highlighting the important role of androgens [male hormones] in COVID-19 disease severity.”

Dr Teresa Murray Amato  has seen many severe cases of COVID. She is chair of emergency medicine at Long Island Jewish Forest Hills in New York City. Though not connected to the new research, but said it “did show a significant correlation between a higher number of androgen receptors and a higher incidence of ICU admissions for patients infected with COVID-19.”

Dr Amato added that, “While the study is small and the exact association is not completely understood, it may show at least one answer to why men were more likely to be admitted to ICU and have overall higher morality with COVID-19 infections.”

According to Amato, further investigations are necessary to determine whether “medications that block androgen receptors will be useful in treating a subset of [COVID-19] patients.”

Since the findings were presented at a medical meeting, they should be considered preliminary until published in a peer-reviewed journal.

Source: Medical Xpress

Categories : Cancer Diet and NutritionTags :

Could Cutting Sugary Drinks Reduce Cancer Risk in Women?

On By ModernMedia

A higher intake of sugar-sweetened beverages (SSBs) in adulthood and adolescence was linked to an increased risk of early-onset colorectal cancer (CRC) in women, according to data from a large prospective study.

The Nurses’ Health Study II followed over 95 000 registered nurses from 1991 to 2015. Those consuming at least two SSB servings a day in adulthood had more than double the early-onset CRC risk of those consuming less than one serving a week. This rose by 16% with each extra serving per day.

In the adolescent years of ages 13 to 18, each serving-per-day increment was associated with a 32% higher risk of early-onset CRC. Meanwhile, replacing each SSB serving per day for adults with a serving of a non-SSB drink was associated with a 17-36% lower risk.

“Considering the well-established, adverse health consequences of SSBs and the highest consumption being characterized in adolescents and young adults under age 50 years, our findings reinforce the public health importance of limiting SSB intake for better health outcomes,” Yin Cao, ScD, MPH, of Washington University in St. Louis, and co-researchers wrote.

Although CRC has been on the decline, the age of early onset — that is, diagnosed before age 50 — has been increasing the past two decades. In comparison to adults born around 1950, those born around 1990 had twice the colon cancer risk and four times the rectal cancer risk.

An estimated 12% of the US population currently consume more than three SSB servings per day, as shown by National Health and Nutrition Examination Survey data. SSBs in the US are often include high fructose corn syrup as an ingredient, as opposed to South Africa which uses cane sugar.

In this study, the population consisted overwhelmingly of white females, ages 25 to 42, with an average age of approximately 42 at enrollment. Over up to 24-plus years of follow-up, 109 cases of early-onset CRC were recorded.

The researchers found that those with higher SSB intakes in adulthood tended to be less physically active and more likely to have a lower endoscopy history, to use non-steroidal anti-inflammatory drugs, and consume red and processed meats. They were also less likely to take multivitamins and to have a reduced intake of alcohol, fibre, folate, and calcium, and to have a poorer diet overall.

No association was found between intake of artificially sweetened beverages or fruit juice in adulthood and risk of early-onset CRC, mirroring past research.

The investigators listed a number of possible pathways for the effect of SSBs on early-onset CRC. 

For example, compared with isocaloric solid foods, energy-containing beverages do not create a feeling of satiation, leading to weight gain. SSBs also initiate rapid blood glucose response and insulin secretion, possibly leading to insulin resistance, inflammation, obesity, and type 2 diabetes — metabolic conditions which are linked to heightened CRC risk.

Other possibilities include intestinal dysbiosis and endotoxemia caused by high fructose levels , the principal sweetener in SSBs in the US and certain other countries, which can impair gut barrier function, increasing gut permeability, and possibly promote cancer formation. A recent experimental study suggested that the high-fructose corn syrup in SSBs from the US enhanced the growth of aggressive tumours in mice, regardless of weight and metabolic syndrome.

High-fructose corn syrup has also been linked to metabolic dysregulation, regardless of obesity.

Fortunately, overall SSB intake has been trending downward in recent years, and Dr Cao and co-authors concluded that further limiting consumption may be “an actionable strategy to curb the rising incidence of [early-onset] CRC.”

Study limitations, the researchers said, included possible unknown confounding variables, the few early-onset CRC cases prevented pinpointing the window of exposure, and there weren’t enough diabetic participants to stratify by a personal history of diabetes. Since the participants were mostly white women, the results were not readily generalisable to other ethnic groups or to men.

Source: MedPage Today

Source Reference: Hur J, et al “Sugar-sweetened beverage intake in adulthood and adolescence and risk of early-onset colorectal cancer among women” Gut 2021; DOI: 10.1136/gutjnl-2020-323450.

Categories : Obstetrics & GynaecologyTags :

Team Investigates The Hazards of Vaping During Pregnancy

On By ModernMedia

Motivated by widely assumed and unproven presumptions that vaping is safer than cigarette smoking, a team at West Virginia University (WVU) is conducting a three-year study on the effects of vaping during pregnancy.

Smoking during pregnancy continues to be a public health problem. It is estimated that around half of women who smoke before becoming pregnant will continue to smoke during and after the pregnancy. Smoking during pregnancy can lead to preterm birth, birth defects and an increased risk of sudden infant death syndrome. Because of this, an increasing number of women who choose to smoke while pregnant are being encouraged to switch to vaping.

“We know that when someone vapes, their blood vessels react by temporarily constricting – or getting smaller, which affects children while in the womb because their fetal environment is also altered,” said contact principal investigator Mark Olfert, associate professor at WVU.

Altering the blood supply in the foetal environment can create a hostile environment for the foetus, leading to serious issues during child and adult life. A previous study in 2018 showed that vaping induced a similar dysfunctional response in the blood vessels of both male and female animals as did smoking cigarettes. So there is great concern that women who are switching to vaping during pregnancy because they think it is safer than smoking are wrong, and that vaping will result in the same problems and complications for offspring as smoking.

Investigations are underway into the reasons behind the harm, and, importantly, what effect these have on the long-term vascular health beyond childhood in offspring that experienced foetal exposure to maternal vaping.

Source: News-Medical.Net

Categories : CancerTags :

Nanoparticles Deliver Chemotherapy to Cancer Cell’s Doorsteps

On By ModernMedia
Fanciful depiction of nanoparticles. Photo by Landon Arnold on Unsplash

New research has developed a nanoparticle system that can deliver large, unwieldy protein-based chemotherapy drugs right to the doorsteps of cancer cells.

Some cancer treatments make use of antibodies’ ability to recognise specific cancer cells in order to target those cells with small active agents, but have not been able to deliver larger protein-based drugs.

Research published in the journal Angewandte Chemie shows how, using a new protein transport system, proteins can arrive at their target intact, protected from destructive proteases by polymer brushes.

Two problems keep coming up when scientists try to develop new anticancer drugs. Firstly, an active agent needs to be able to kill the body’s cells at the root of the cancer, and secondly it should be active in target cancer cells rather than in healthy cells. To this end, some medical researchers are  trying to implement a cargo package as a method of delivery. The active agent stays protected and packaged until it reaches the target location, while antibodies that only attach to cancer cells help with “finding the right address”. 

These antibodies recognise specific receptor structures on the outer membrane of cancer cells, attaching to these structures with the cell absorbing the active agent. However, this strategy is unsuccessful when the active agents are large proteins. 

These large proteins are usually water soluble, and unable to penetrate the cell membrane. The body’s own protease enzymes throw in another complication, because they break down the protein cargoes before they can reach their target location.

Sankaran Thayumanavan and colleagues at the University of Massachusetts in Amherst, USA, have now developed a protected nanosized cargo package, which meets both requirements of targeted delivery and keeping the cargo intact. For the container, they use miniscule beads made of silicon dioxide with a diameter of just 200 nanometres. The surface of these beads is coated with brush-like polymer strands made of polyethylene glycol (PEG) that can be doubly functionalised, giving tiny “brush beads”. This is termed a protein-antibody conjugate (PAC).

With simple click chemistry, the researchers attach the desired active-agent protein and antibodies to the polymer bristles. The finished bead-shaped packages have antibodies on the outermost layer, with the proteins safely concealed in the forest of polymer strands.

Besides the ability to transport water-soluble proteins, this PAC also possessed another advantage: a possible high protein-antibody ratio. The researchers said that, at least in theory, over 10 000 proteins could be transported per (expensive) antibody using the researchers’ PACs, compared to the maximum of four active agents per antibody in previous antibody-drug combinations.

The team tested their system on various cell cultures with different antibodies and test proteins. The test was a success; the PACs delivered their deadly cargoes to their cellular targets as planned.
The team is now going to figure out if and how the packages can be shielded from macrophages. They are optimistic about this because the PEG functionalities and the surface antibodies are designed for a quick delivery while minimising clearance by macrophages.

Source: News-Medical.Net

Journal information: Liu, B., et al. (2021) Protein–Antibody Conjugates (PACs): A Plug‐and‐Play Strategy for Covalent Conjugation and Targeted Intracellular Delivery of Pristine Proteins. Angewandte Chemie International Edition. doi.org/10.1002/anie.202103106.

Categories : COVIDTags :

Why COVID is So Hard to Treat

On By ModernMedia
The SARS-CoV-2 coronavirus. Photo by CDC on Unsplash

A comprehensive review of what is so far known about the coronavirus its functions suggests the virus has a unique infectious profile, explaining why COVID is so difficult to treat and often leaves survivors with debilitating ‘long COVID’ symptoms.

In a review recently published in The Lancet Respiratory Medicine, the authors review what is currently known about COVID, and find that it works differently to most pathogens.   

Evidence increasingly points to the virus infecting both the upper and lower respiratory tracts. In contrast, ‘low pathogenic’ human coronavirus sub-species typically settle in the upper respiratory tract, causing cold-like symptoms, while ‘high pathogenic’ viruses, such as those that cause SARS and ARDS, typically settle in the lower respiratory tract.

Additionally, COVID has evolved a uniquely challenging set of characteristics as evidenced by more frequent multi-organ impacts, blood clots, and an unusual immune-inflammatory response not commonly associated with other similar viruses.

While animal and experimental models imply an overly aggressive immune-inflammation response is a key driver, it seems things work differently in humans: Although inflammation is a factor, it is a unique dysregulation of the immune response that causes our bodies to mismanage the way they fight the virus.

This could explain the ‘long COVID’ phenomenon that some people experience after infection, struggling with significant health issues months after infection. Long COVID is characterised by symptoms of fatigue, headache, difficulty breathing and loss of sense of smell. It is more likely with increasing age, body mass index and female sex

“The emergence of severe acute respiratory syndrome coronavirus two (SARS-CoV-2), which causes COVID-19, has resulted in a health crisis not witnessed since the 1918 Spanish flu pandemic. Tragically, millions around the world have died already,” said co-author Ignacio Martin-Loeches, Clinical Professor in Trinity College Dublin’s School of Medicine, and Consultant in Intensive Care Medicine at St James’s Hospital.

“Despite international focus on the virus, we are only just beginning to understand its intricacies. Based on growing evidence we propose that COVID-19 should be perceived as a new entity with a previously unknown infectious profile. It has its own characteristics and distinct pathophysiology and we need to be aware of this when treating people.

“That doesn’t mean we should abandon existing best-practice treatments that are based on our knowledge of other human coronaviruses, but an unbiased, gradual assembly of the key COVID-19 puzzle pieces for different patient cohorts—based on sex, age, ethnicity, pre-existing comorbidities—is what is needed to modify the existing treatment guidelines, subsequently providing the most adequate care to COVID-19 patients.”

Source: Medical Xpress

Journal information: Marcin F Osuchowski et al, The COVID-19 puzzle: deciphering pathophysiology and phenotypes of a new disease entity, The Lancet Respiratory Medicine (2021). DOI: 10.1016/S2213-2600(21)00218-6

Categories : Diseases, Syndromes and Conditions New Compounds and TreatmentsTags :

Experimental Inhibitor Drug Shows Promise For The Deadly Marburg Virus

On By ModernMedia
Photo by CDC on Unsplash

The lethal Marburg virus, a relative of the Ebola virus, causes a serious haemorrhagic fever with an extremely high fatality rate and has had no known treatment — until now. 

Marburg virus infects human and primates, the disease currently has no approved vaccine or antivirals for prevention or treatment. In two larger recent outbreaks in the DRC in 1998–2000, and in Angola in 2004–2005, Marburg had extremely high fatality rates of 83% and 90%.

A team of researchers is working to change that. In a new paper in the journal Antimicrobial Agents and Chemotherapy, investigators from Penn’s School of Veterinary Medicine, working together with scientists from the Fox Chase Chemical Diversity Center and the Texas Biomedical Research Institute, report encouraging results from tests of an experimental antiviral targeting Marburg virus.

The new compound prevents viruses from leaving infected cells, thus halting the spread of infection. In a first, this new class of inhibitors was shown to be effective against infection in an animal model.

Additionally, possible similarities in virus-host interactions between Marburg and SARS-CoV-2, prompted the team to conducted experiments on the coronavirus. Unpublished preliminary results appeared encouraging.

“It really is exciting. These viruses are quite different but may be interacting with the same host proteins to control efficient egress and spread, so our inhibitors may be able to block them both,” said co-corresponding author Ronald Harty, Professor, Penn’s School of Veterinary Medicine.

Prof Harty’s team have been developing an antiviral that instead of targeting the virus known as “host-oriented.” By blocking the proteins in host cells that viruses hijack during late stages of infection, preventing virus-host interactions.

This method helps prevent a virus evolving resistance, but it also makes it more likely that a drug could be used against multiple viruses, as many make use of the same machinery in the host cell to reproduce and spread.

The Marburg and Ebola viruses use protein known as VP40 to interact with a host protein called Nedd4 to allow the completed viruses to ‘bud off’ of the host cell, which is a key part of viral replication.

Previously, they had tested a variety of small molecule inhibitors of this process using laboratory tests that relied on non-infectious and more-benign viral models. Those assays led them to a promising candidate, FC-10696, for further study.

The researchers firstly tested the chosen inhibitor for safety and its useful duration within the body. Next, since the real Marburg virus is too dangerous to study safely in anything but a Biosafety Level 4 (BSL-4) laboratory, they used an assay to look at what are known as virus-like particles, or VLPs, which are non-infectious but can bud off of a host cell.

Using the Biosafety Level 2 laboratory at Penn, “it’s a very quick way we can test these inhibitors,” said Prof Harty.

The researchers saw a dose-dependent response to FC-10696 on VLP budding in cells tested the compound using the real Marburg virus. These studies were done in a BSL-4 lab at Texas Biomedical Research Institute and found the compound inhibited the budding and spread of live Marburg virus in two human cell types, including in macrophages, an immune cell type commonly infected by the virus.

As a final step, they tested the compound in mice infected with Marburg virus. That received the treatment took longer to display disease symptoms and had a reduced viral load.

“These are the first promising in vivo data for our compounds,” said Prof Harty. “Whereas the control group all became sick very quickly and died, with the treated animals there was one survivor and others showed delayed onset of clinical symptoms. It’s showing that our inhibitors are having an effect.”

Source: News-Medical.Net

Journal information: Han, Z., et al. (2021) Compound FC-10696 Inhibits Egress of Marburg Virus. Antimicrobial Agents and Chemotherapy. doi.org/10.1128/AAC.00086-21.