Slow down, ageing cells
werner's syndrome is a malignancy affecting only a small number of people, but shows devastating manifestations. The victims are cruelly wizened and grey by the time they reach their late 20's. They await their death from prematurely clogged arteries and heart malfunctions in their late 40s or 50s. The cause has been attributed to two copies of a defective gene that they carry. Gerald Schellenberg, University of Washington, Seattle and David Galas of Darwin Molecular, a biotechnological company, have traced the identity of Werner's gene encoding the enzyme dna helicase. Helicase performs some vitally important functions in a healthy cell: it helps the dna to unwind for replication and activation of genes and it also helps dna repair enzymes to rectify random chromosomal mutations and breakages which constantly threaten the integrity of genes and chromosomes. But helicase is definitely only a member of the crew that works round the clock, to keep the cells in good shape.
Since ages, the research into ageing has centred around bizarre elixirs attempting to rejuvenate flagging libido. Medicine's aspiration to keep people alive in their old age is far outstripping its hope to restore the vigour of their youthful years. And this reality is driving a new assault on the underlying causes of ageing. Brittle bones, grey hair, saggy skin, loss of immunity, forgetfulness, cancers and strokes are but a few hallmarks of ageing. But inside each cell of the body, the scene is much more complicated and dramatic. The landscape is dominated by chromosomes fraying away with their ends, technically called telomeres, clocking up random mutations all along their length, molecular debris piling up, the membranes showing signs of wear and tear, and degeneration. The useful genes that had served the body through years, start shutting down for good, and less desirable, hitherto unknown genes, spring into action to cause havoc. If these changes are halted or reversed, ageing will no longer be the inevitable consequence of a long life.
If strengthening the repair system of the cell is one way to achieve longevity, another is to curb the rate at which damage occurs in the first place. Jeff Poulin and his group at the University of Arizona, Tucson have reported that high doses of vitamin e slows the ageing process of brain and immune cells of mice. It strengthens a long known scientific theory that antioxidant vitamins neutralise reactive free radicals and