Sharkman

WASHINGTON: A complex compound produced by sharks could be used in the fight against deadly human viruses, American researchers have discovered.

Squalamine, manufactured from the liver of the dogfish shark, was discovered in 1993 but a new study has found potential uses against human viruses.

Researchers tested squalamine in lab dishes and in animal subjects and found it could inhibit or control viral infections and in some cases appeared to cure animals of their ills.

Michael Zasloff, a professor of surgery and paediatrics at Georgetown University Medical Centre and the project's lead investigator, sent samples of squalamine to a series of labs around the US for testing.

Tissue cultures showed it could ''inhibit the infection of human blood vessel cells by the dengue virus and human liver cells infected with hepatitis B and D''.

Research on animals showed the compound controlled yellow fever, Eastern equine encephalitis virus and murine cytomegalovirus, a rodent herpes virus.

''It is clearly a promising drug and is unlike, in its mechanism of action and chemical structure, any other substance currently being investigated to treat viral infections,'' said Professor Zasloff. ''We have not yet optimised squalamine dosing in any of the animal models we have studied and as yet we do not know the maximum protective or therapeutic benefit that can be achieved in these systems.

''But we are sufficiently convinced of the promise of squalamine as an antiviral agent that we intend to take this compound into humans.

Squalamine is safe for humans and has been considered a potential tool against cancer and eye diseases. The compound has been synthesised in a lab since 1995 and is no longer extracted directly from shark tissue.

''In several of the early trials squalamine has shown significant and promising activity … in both certain forms of cancer and in diabetic retinopathy,'' Professor Zasloff, who discovered squalamine in 1993, said.

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