Lower cholesterol could help fight viruses

Cutting cholesterol could help the body's immune system fight viral infections, researchers in Scotland have suggested.

The scientists, from the University of Edinburgh, said they had found a "direct link" between the workings of the immune system and cholesterol levels in the body.

Their research, published in the journal PLoS Biology, found that when the body succumbs to a viral infection a hormone in the immune system sends signals to blood cells, causing cholesterol levels to fall. Cholesterol produced by the body is needed by viruses and certain types of bacteria to maintain growth.

Limiting the body's production of cholesterol would help curb the opportunity for the viruses to thrive by cutting off this source of energy.

The researchers said the findings could lead to new ways of treating viral infections, targeting the actions of cholesterol in the body.

Currently drugs such as antibiotics are used to fight infections by targeting the bug directly.

But a new treatment would help overcome the problems associated with antibiotic resistance, as it enhances the way the body responds to an infection, instead of focusing on attacking the infection itself.

Cholesterol is a fatty substance which is found in the blood and is mainly made in the body.

The substance plays an essential role in how cells in the body work, but too much cholesterol in the blood can increase the risk of heart problems.

A common cause of high blood cholesterol levels is eating too much saturated fat and people are often advised to change their diet to reduce their risk of heart problems.

Doctors also frequently prescribe drugs known as statins which help lower cholesterol and cut people's risks. Statins are one of the most commonly prescribed drugs in Scotland.

It now seems that reducing cholesterol levels could have an extra benefit in helping the body to fight infections.

Professor Peter Ghazal, of the university's Division of Pathway Medicine, said cutting off the supply of cholesterol needed by viruses could help in the battle against infections.

"What we have discovered is that a key immune hormone stimulated upon infection can lower cholesterol levels and thereby deprive viral infections of the sustenance they need to grow," the researcher said.

"Drugs currently exist to lower cholesterol levels, but the next step would be to see if such drugs would also work to help bolster our immune systems."

The research was funded by the Wellcome Trust, the Biotechnology and Biological Sciences Research Council, the Engineering and Physical Sciences Research Council and the British Heart Foundation (BHF).