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Spinal cord injury: Gel treatment allows paralysed mice to walk again

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A self-assembling gel that stimulates nerve regeneration has shown promise as a treatment for paralysis in mice



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11 November 2021

A section of the spinal cord in a mouse treated with the gel, showing regenerated nerve fibres in red

Samuel I. Stupp

A self-assembling gel injected at the site of spinal cord injuries in paralysed mice has enabled them to walk again after four weeks.

The gel mimics the matrix that is normally found around cells, providing a scaffold that helps cells to grow. It also provides signals that stimulate nerve regeneration.

Samuel Stupp at Northwestern University in Chicago and his colleagues created a material made of protein units, called monomers, that self-assemble into long chains, called supramolecular fibrils, in water.

When they were injected into the spinal cords of mice that were paralysed in the hind legs, these fibrils formed a gel at the injury site.

The researchers injected 76 paralysed mice with either the fibrils or a sham treatment made of salt solution, a day after the initial injury. They found that the gel enabled paralysed mice to walk by four weeks after the injection, whereas mice given the placebo didn’t regain the ability to walk.

The team found that the gel helped regenerate the severed ends of neurons and reduced the amount of scar tissue at the injury site, which usually forms a barrier to regeneration. The gel also enhanced blood vessel growth, which provided more nutrients to the spinal cord cells.

“The extent of functional recovery and solid biological evidence of repair we observed using a model that truly emulates the severe human injury makes the therapy superior to other approaches,” says Stupp.

Other experimental treatments being developed for paralysis use stem cells, genes or proteins and have questionable safety and effectiveness, says Stupp.

The walking ability of mice was assessed in two ways. First, the mice were given an overall score to represent their ankle movement, body stability, paw placement and steps. Mice treated with the gel had a score three times higher than sham-treated mice.

The team also assessed walking ability by dipping the hind legs of the mice in coloured dyes and letting them walk across a narrow runway lined with white paper. This test showed that the gel increased both stride width and length.

“A higher stride length and width should correlate with more regrown axons [nerve fibres] innervating the muscles of the leg,” says Stupp.

The gel’s regenerative effect is due to short sequences of amino acids attached to the ends of the monomer proteins. These sequences provide regenerative signals that are picked up by receptors on the surface of spinal cord cells.

By altering the non-signal part of these monomers, the team found that enhancing the ability of the molecules to shift in and out of the larger fibril structure enhanced the recovery of mice, probably because the increased motion enabled the signals to engage with more receptors on the cells.

“It would be very exciting if this finding could translate to humans, though issues of scaling mouse therapies to humans are not trivial,” says Ann Rajnicek at the University of Aberdeen, UK.

Journal reference: Science,, DOI: 10.1126/science.abh3602

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Solar storms may cause up to 5500 heart-related deaths in a given year

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In an approximate 11-year cycle, the sun blasts out charged particles and magnetised plasma that can distort Earth’s magnetic field, which may disrupt our body clock and ultimately affect our heart



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17 June 2022

A solar storm

Jurik Peter/Shutterstock

Solar storms that disrupt Earth’s magnetic field may cause up to 5500 heart-related deaths in the US in a given year.

The sun goes through cycles of high and low activity that repeat approximately every 11 years. During periods of high activity, it blasts out charged particles and magnetised plasma that can distort Earth’s magnetic field.

These so-called solar storms can cause glitches in our power grids and bring down Earth-orbiting satellites. A handful of studies have also hinted that they increase the risk of …

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UK Covid infection rate rising, with more than a million cases in England | Coronavirus

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Coronavirus infections are rising in the UK, figures have revealed, with experts noting the increase is probably down to the more transmissible BA.4 and BA.5 Omicron variants.

The figures from the Office for National Statistics (ONS), based on swabs collected from randomly selected households, reveal that in the week ending 11 June an estimated one in 50 people in the community in England are thought to have had Covid – around 1.13 million people.

The figure is even higher, at one in 45, in both Wales and Northern Ireland, while it was highest in Scotland where, in the week ending 10 June, one in 30 people are thought to have been infected.

While the figures remain below the peak levels of infection seen earlier this year, when around one in 13 people in England had Covid, the findings are a rise on the previous week where one in 70 people in England were thought to be infected. Furthermore, the data reveals increases in all regions of England, except the north-east, and across all age groups.

Experts say that a key factor in the increase is probably the rise of the Covid variants of concern BA.4 and BA.5.

“Infections have increased across all four UK nations, driven by rising numbers of people infected with the BA.4 and BA.5 Omicron variants,” said Kara Steel, senior statistician for the Covid-19 Infection Survey.

While Steel said it remained too early to say if this was the start of another wave, others have warned it may already have begun, with increased mixing and travelling among other factors fuelling a rise in cases.

Among concerns scientists have raised are that BA.4, BA.5 and another variant on the rise, BA.2.12.1, replicate more efficiently in human lung cells than BA.2.

Prof Azra Ghani, an epidemiologist at Imperial College London, said the latest figures were not surprising, and might rise further.

“This increase in infection prevalence is likely due to the growth of the BA.4 and BA.5 Omicron subvariants, which as we have seen elsewhere in Europe, appear to be able to escape immunity generated from previous Omicron subvariants,” she said.

“It is therefore possible that we will continue to see some growth in infection prevalence in the coming weeks and consequently an increase in hospitalisations, although these subvariants do not currently appear to result in any significantly changed severity profile. This does however serve as a reminder that the Covid-19 pandemic is not over.”

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NHS to offer women in England drug that cuts recurrence of breast cancer | Breast cancer

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Thousands of women in England with breast cancer are to benefit from a new pill on the NHS which reduces the risk of the disease coming back.

The National Institute for Health and Care Excellence (Nice) has given the green light to abemaciclib, which cuts the chance of breast cancer returning after a patient has had surgery to remove a tumour.

Trials showed that patients who had the drug with hormone therapy had a more than 30% improved chance of their cancer not coming back after surgery, compared with hormone therapy alone.

“It’s fantastic thousands of women with this type of primary breast cancer will now have an additional treatment option available on the NHS to help further reduce the risk of the disease coming back,” said Delyth Morgan, the chief executive of charity Breast Cancer Now.

“The fear of breast cancer returning or spreading to other parts of their body and becoming incurable can cause considerable anxiety for so many women and their loved ones.

“New effective treatments such as abemaciclib, which can offer more women the chance to further reduce the risk of the disease recurring, are therefore extremely welcome and this is an important step change in the drug options available for this group of patients.”

The twice-a-day pill is suitable for women with hormone receptor-positive, HER2-negative, node-positive early breast cancer at high risk of recurrence who have had surgery. About 4,000 women will benefit initially, Nice said.

Helen Knight, the interim director of medicines evaluation at Nice, said the draft recommendation came less than a month after abemaciclib received its licence.

“The fact that we have been able to produce draft recommendations so quickly is testament to the success of our ambition to support patient access to clinically and cost effective treatments as early as possible,” said Knight. “Until now there have been no targeted treatments for people with this type of breast cancer.

“Abemaciclib with hormone therapy represents a significant improvement in how it is treated because being able to have a targeted treatment earlier after surgery will increase the chance of curing the disease and reduce the likelihood of developing incurable advanced disease.”

Abemaciclib works by targeting and inhibiting proteins in cancer cells which allow the cancer to divide and grow. It normally costs £2,950 for a packet of 56 150mg-tablets, but the manufacturer, Eli Lilly, has agreed an undisclosed discounted price for NHS England.

“Thanks in part to this latest deal struck by NHS England, NHS patients will be able to access another new targeted drug for a common and aggressive form of breast cancer,” said Prof Peter Johnson, the cancer director of NHS England.

“Abemaciclib, when used alongside a hormone therapy, offers a new, doubly targeted, treatment option, helping to increase the chances of beating the cancer for good, as well as meeting the NHS’s commitment to delivering improved cancer care under our long-term plan.”

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