• Home
  • Health & Wellness
  • Disclaimer
    • Terms of Use
    • Privacy Policy
    • DMCA Notice
Podcast
  • Home
  • Health & Wellness
  • Disclaimer
    • Terms of Use
    • Privacy Policy
    • DMCA Notice
24/7 Health News
No Result
View All Result
Home Article

The unusual ways viruses and parasites use their cell membranes to spread – and how scientists are fighting back

October 27, 2022
in Article
0
The unusual ways viruses and parasites use their cell membranes to spread – and how scientists are fighting back
file 20221025 3834 llifm3
Red onion skin cells seen through a microscope. Claudio Divizia/Shutterstock

Cell membranes make up the exterior of all cells and are a basic structure found in most living organisms. But they can also help parasites survive in the human body, play an important part in cancer growth and enclose and protect deadly viruses, including the one that causes COVID. Scientists are looking to understand how bilayers (cell membranes with two layers) work and whether they can be used to develop new drugs to combat infections.

It has been known for a long time that living cells are enclosed by a fatty layer that separates different cells. This can be clearly seen in red onion skin cells in which the dye that gives the onion its distinctive colour is confined in these layers. Building on previous work, Seymour Singer and Garth Nicolson suggested a structure for this layer in 1972 which they called the fluid mosaic model.

Red onion cut in half revealing red layers.
Visible bilayers.
Jiang Hongyan/Shutterstock

Their model has since been found to explain many features in living organisms. The bilayer is even part of the structure and function of many viruses such as influenza and SARS-Covid-2. Viral particles can use it as a protective layer which helps them to spread. For example, we can trace how a viral particle of SARS-Covid-2 enters a lung cell and what happens next.

When one of these viral particles enters a lung cell, it releases its ribonucleic acid (RNA) – single-stranded genetic code. This translates into viral proteins on ball-like structures called ribosomes that are attached to membranes inside the host cell. These viral proteins are then transported to another part of the cell called the Golgi apparatus which encloses them in lipid (fatty) bilayers. They then make a further journey, fusing with the surface membrane of the cell, before leaving it altogether – a process known as exocytosis.

Man coughing into clenched fist.
Virus particles go through a number of changes before spreading.
Ralf Geithe/Shutterstock

When the virus leaves the cell it carries some of the membranes from the host cell with it. And the virus – now carrying a protective coat – will attempt to infect another lung cell or be released into the air as we breathe or cough.

Disrupting the virus

Biochemists in a team led by Valerie O’Donnell at Cardiff University are trying to find out more about this bilayer with the hope that drugs could be designed to combat the virus itself. By growing the COVID virus in the laboratory and extracting the lipid from it, they have found that its surface membrane is very different from that of the host surface membrane – it has much less cholesterol and sphingomyelin (a fatty lipid component) and many more lipids which can increase blood clotting.

When we look at the way the virus acquires its membrane, a number of drugs might be used to disrupt its pathway. This has been done before. Scientists working with tubercle bacilli in the 1950s showed that certain harmless detergents disrupted the tuberculosis infection they cause. With COVID, widespread handwashing, using hand sanitiser and mouth washing attacked the virus’ bilayer and destroyed it.

Perhaps the virus will produce, by mutation, a new strain that has a tougher bilayer. The Cardiff laboratory is looking into the lipid composition of different strains and the results may indicate novel pathways for evolution of viruses and their treatment.

Other roles for bilayers

file 20221025 23 poplij
Schistosoma larvae change to survive in human blood.
Mohammed_Al_Ali/Shutterstock

Bilayers are also involved in the infection of humans by diseases such as schistosomiasis (also known as bilharzia). Infective larvae swimming in water penetrate human skin and the bilayer on the larval surface immediately changes to a unique double layer to allow it to survive in human blood. The larvae then covers itself with lipids from this blood and scientists have suggested that this disguises the membrane from the immune response of hosts – in other words, us.

Another hypothesis put forward by scientists in Egypt about the toughness of this double bilayer comes from the amount of sphingomyelin, which they found protects the membrane by forming hydrogen bonds at the surface. This is thought to prevent access to immune antibodies and cells. Reducing the amount of sphingomyelin with arachidonic acid – a fatty acid found in the body and also used in some supplements – can act as a drug against the disease. It is usually used in combination with another drug called praziquantel which attacks the parasite’s membrane.

One exception to the generalisation that bilayers are in all living cells are the parasitic and soil nematodes. Enormous numbers of these are found in soil: ones that do not affect other plants or animals such as Caenorhabditis, but also numerous other animal and plant parasitic species in the tropics and temperate zones. These organisms have a surface in which lipids are thought to be arranged in unusual hexagonal structures to form large rafts which give an alternative structure to the bilayer found in most cells.

Study of lipids can surprise us and lead to new ideas about life and its structure, but also, excitingly, towards drugs that can be developed to disturb the structure of the lipid membranes of pathogens, cancers and other human infections.

The Conversation

John Kusel does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.

ShareTweetSharePin
Previous Post

Anti-obesity strategy could be world leading – let’s not lose momentum

Next Post

Deprivation in childhood linked to impulsive behaviour in adulthood – new study

Next Post

Deprivation in childhood linked to impulsive behaviour in adulthood – new study

Most Read

What causes stuttering? A speech pathology researcher explains the science and the misconceptions around this speech disorder

What causes stuttering? A speech pathology researcher explains the science and the misconceptions around this speech disorder

December 15, 2022
morning back pain

Morning Again Ache Trigger Is Not the Mattress

October 11, 2021
lower back pain relief exercises

5 decrease again ache aid workouts

October 11, 2021
3 years after legalization, we have shockingly little information about how it changed cannabis use and health harms

3 years after legalization, we have shockingly little information about how it changed cannabis use and health harms

October 15, 2021
Nasal vaccines promise to stop the COVID-19 virus before it gets to the lungs – an immunologist explains how they work

Nasal vaccines promise to stop the COVID-19 virus before it gets to the lungs – an immunologist explains how they work

December 14, 2022
bleeding in gum

When The Bleeding in gum Is Severe ?

October 11, 2021
Good Night Sleep

6 Causes of Good Evening Sleep

October 11, 2021

COVID vaccines: how one can pace up rollout in poorer international locations

October 5, 2021
Ten small changes you can make today to prevent weight gain

Ten small changes you can make today to prevent weight gain

October 12, 2021
Support and collaboration with health-care providers can help people make health decisions

Support and collaboration with health-care providers can help people make health decisions

December 16, 2021
Greece to make COVID vaccines mandatory for over-60s, but do vaccine mandates work?

Greece to make COVID vaccines mandatory for over-60s, but do vaccine mandates work?

December 1, 2021

Multiple sclerosis: the link with earlier infection just got stronger – new study

October 12, 2021
News of war can impact your mental health — here’s how to cope

Binge-eating disorder is more common than many realise, yet it’s rarely discussed – here’s what you need to know

December 2, 2022
Nurses’ attitudes toward COVID-19 vaccination for their children are highly influenced by partisanship, a new study finds

Nurses’ attitudes toward COVID-19 vaccination for their children are highly influenced by partisanship, a new study finds

December 2, 2022
Kick up your heels – ballroom dancing offers benefits to the aging brain and could help stave off dementia

Kick up your heels – ballroom dancing offers benefits to the aging brain and could help stave off dementia

January 3, 2023
How hot is too hot for the human body? Our lab found heat + humidity gets dangerous faster than many people realize

How hot is too hot for the human body? Our lab found heat + humidity gets dangerous faster than many people realize

July 6, 2022
The promise of repairing bones and tendons with human-made materials

The promise of repairing bones and tendons with human-made materials

January 4, 2022
As viral infections skyrocket, masks are still a tried-and-true way to help keep yourself and others safe

As viral infections skyrocket, masks are still a tried-and-true way to help keep yourself and others safe

December 14, 2022
How regulatory agencies, not the courts, are imposing COVID-19 vaccine mandates

How regulatory agencies, not the courts, are imposing COVID-19 vaccine mandates

October 24, 2021
Heart disease risk from saturated fats may depend on what foods they come from – new research

Heart disease risk from saturated fats may depend on what foods they come from – new research

November 29, 2021
Late night eating may cause greater weight gain – new research points to why

Late night eating may cause greater weight gain – new research points to why

October 12, 2022

10 Things I Learned During My Body Transformation

October 12, 2021

7 Health Benefits of Sweet Potatoes

October 12, 2021
Nobel prize: how chilli peppers helped researchers uncover how humans feel pain

Nobel prize: how chilli peppers helped researchers uncover how humans feel pain

October 12, 2021
How air filters can make COVID wards safer for patients and staff

How air filters can make COVID wards safer for patients and staff

December 1, 2021
GPs don’t give useful weight-loss advice – new study

GPs don’t give useful weight-loss advice – new study

December 16, 2022
Four ways to avoid gaining weight over the festive period – but also why you shouldn’t fret about it too much

Four ways to avoid gaining weight over the festive period – but also why you shouldn’t fret about it too much

December 22, 2022
Five ways to avoid pain and injury when starting a new exercise regime

Five ways to avoid pain and injury when starting a new exercise regime

December 30, 2022
Why suicide prevention support is crucial for people with fetal alcohol spectrum disorder

Why suicide prevention support is crucial for people with fetal alcohol spectrum disorder

September 28, 2022
Too hot to handle: Climate considerations for youth sport during the hottest years on record

Too hot to handle: Climate considerations for youth sport during the hottest years on record

July 19, 2022
  • Home
  • Health & Wellness
  • Disclaimer

© 2020 DAILY HEALTH NEWS

  • Home
  • Health & Wellness
  • Disclaimer
    • Terms of Use
    • Privacy Policy
    • DMCA Notice

© 2020 DAILY HEALTH NEWS