Doctors believe that the anti-inflammatory effects of the painkillers, called NSAIDS, may help keep brain cells alive.

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Elsewhere, cardiologists are testing whether patients with inflamed vessels might benefit from existing cholesterol medications, which also may have anti-inflammatory effects.

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It may be that aspirin's success could be due to some of its other properties, such as anti-inflammatory effects, they said.

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Circumin is also being studied for possible anti-inflammatory effects in other diseases.

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Anti-inflammatory effects may be another factor.

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Treatment usually involves anti-inflammatory drugs and steroid injections, but side effects are common.

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They are designed to cause less side effects in patients than the more common non-steroidal anti-inflammatory drugs (NSAIDS).

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Dr Margherita Cantornas, who led the study at Penn State University in the US, said that the anti-inflammatory properties of vitamin D could allow the dosage of steroids to be reduced, cutting the side effects.

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