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POPE BENEDICT XVI SAYS AN IMMORTALITY PILL MIGHT NOT BE SUCH A GOOD THING. Vatican City: The 80-year-old pontiff says its better not to hope for biological life that can be made to last forever (1)
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The Drosophila mutant Methuselah (mth) was identified from a screen for single gene mutations that extended average lifespan. mth mutants have a 35% increase in average lifespan and increased resistance to several forms of stress...(2)
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I dont want to achieve immortality through my work; I want to achieve it through not dying. I dont want to live on in the hearts of my countrymen; I want to live on in my apartment (3)
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Woody Allen
METHUSELAH AND THE "SUN"
For reasons clear to His Holiness Benedict XVI, if not to Woody Allen, more folks bet on eternal paradise than on permanent rent control. Last March, while delivering a homily near St. Peters Square, the pope reflected on the limits of science. Pleading for the faithful to "drink from the fountain of life itself," i.e., spiritual immortality, he warned that extending life past its natural limits would crowd the world with old people. There would be no room on earth "for youth, for this newness of life" (4)
. Im afraid, though, that his warning was a tad late; modern science has already helped break the biblical rule that "the days of our lives are threescore years and ten" (5)
. The pope has himself beaten the odds. Thanks to advances in medical management, the octogenarian pontiff has survived two strokes and congestive heart failure.
Biological immortality might not lurk around the corner, but were working on it. In the lab, thanks to the biological revolution, weve "immortalized" lines of human cells in a dish, cloned DNA from the dead, and extended by tenfold the natural lifespan of yeasts (6)
. Flies, worms, and rodents live up to 40% longer when fed a diet that has at least 30% fewer calories than usual (7)
, while resveratrol from red wine can keep them fit (8)
. Reporting on Leonard Guarentes analysis of how caloric restriction extends life, The New York Times enthused: "Actuaries, put down your gloomy mortality tables and sharpen your pencils. Heirs and legatees, contain yourselves in patience. If any such drug were to work in humans the same way that this diet of 30 percent less than normal calories works in laboratory rodents, people would start enjoying a maximum life span of 170 years, most of it in perfect health" (9)
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And sure enough, news came last summer that an immortality pill is nigh: "Super Fruit Fly May Lead To Healthier Humans; Aging Slowed With Single Protein" (10)
. Richard Roberts of University of Southern California (Los Angeles, CA, USA) and Seymour Benzers group at California Institute of Technology (Pasadena, CA, USA) have made peptides that target the Methuselah (mth) gene in fruit flies. Insects with mutations in this gene have a 35% increase in average lifespan and increased resistance to several forms of stress, including heat, starvation, and oxidative damage. The protein affected by this mutation is related to a G protein-coupled receptor of the secretin family and is switched on by a ligand named Sun. By means of a novel mRNA display selection technique, which Roberts developed, the Pasadena group identified high-affinity peptides that bind to the N-terminal ectodomain of mth and prevent binding of Sun to its target (11)
. As humans, like flies, have secretin-like receptors on many of our cells, this sun-screen, as it were, could be a forerunner to the pontiffs "immortality pill." As Woody Allen might say, we should live so long.
THE EVENING HEMISPHERE
Weve actually been heading in that direction for more than a century. In the 1850s, American life expectancy was 39.5 years, and poet James Russell Lowell complained:
These days, age 40 seems closer to noon than evening. American life expectancy is now nearly 80, and our maximum lifespan has also increased. The bean counters of Medicare predict that by 2010, theyll have 50,000 centenarians on their payroll (13)
. The trend is global: The oldest Swedes now die at age 108, eight years later than their counterparts in 1860 (14)
. The days of our lives are no longer threescore years and ten.
A Chinese official boasts that "Chinese Life Expectancy Rises by 41 Years in One Century," from just over 30 years in 1900 to 70.1 in 2000. He attributes the new longevity of Chinas people to "the advancement of science and technology, especially in medical science" (15)
. Pace, Pope Benedict, the Chinese young have not been crowded out by old folks. When the pontiff urged a moratorium on immortality pills, Id bet that he was hooked up to a sound system manufactured by one of the 300 million Chinese under 25 who now walk the earth because of one or another pill.
The longer the days of our lives, the longer the days of waning powers. Theres that "Catskill" story about the 87-year-old man who marries an 83-year-old woman he met in a senior center. They take their honeymoon in a rented bungalow by the sea. The woman retires upstairs first and calls out to her husband, "Come upstairs and make love!" He replies, "I cant do both!"
NO COUNTRY FOR OLD MEN
The upside? "Bodily decrepitude is wisdom; young/We loved each other and were ignorant", insisted William Butler Yeats (16)
. Clearly, the more folks hobble and creak, the more likely they are to conflate their nostalgia for youth with a pipe dream of paradise. Yeats found that vision in the Byzantine mosaics of Ravenna:
Yeats was 63 years old when he wrote "Sailing to Byzantium" and like poets before and after, equated longevity with decrepitude. He mourned that "An aged man is but a paltry thing/A tattered coat upon a stick" and that his heart was "fastened on a dying animal". But there was pie in the sky of Byzantium. Yeats looked forward to being gathered "into the artifice of eternity", where in avian form, he would be
Yeats resigned from the Irish Senate for "reasons of health" in the year that the poem was published. Tattered and paltry, perhaps, but he stuck out the years of hobble and creak for 11 more years, until in W. H. Audens words: "The current of his feeling failed; he became his admirers" (18)
. His admirers have kept Yeats very much alive: this spring, the film "No Country for Old Men" picked up four Oscars; Jonathan Spottiswoodes rock lyric "Sailing to Byzantium" is climbing the charts (19)
; and Philip Roths "The Dying Animal" is in many of the bookstores (20)
. To what avail? Although Yeats may have achieved immortality through his work—and live on forever in the hearts of men—hes no longer living in his apartment.
FREUD, TITHONUS, AND TENNYSON
Unlike Yeats or the pontiff, Sigmund Freud was as skeptical of the afterlife as Woody Allen. At mid-life in the Vienna of 1911, Freud scoffed at spiritual immortality: "The doctrine of reward in a future life for the renunciation of earthly lusts is nothing but a mythical projection" (21)
. But age and illness convinced Freud that the land of pain is no country for old men. Aged 80 and exiled in London, mauled by bouts of surgery and radium treatment for oral cancer, Freud turned to the kindly Fates of the Greek myth:
Perhaps the gods are kind to us in making life more disagreeable as we grow older. In the end death seems less intolerable than the manifold burdens we carry (22).
As he wrote these lines in his study, Freud was attended by a goddess. Eo, goddess of dawn, is limned in clay on an Athenian Lekythos, which stood by his desk. This red-figured oil jug, which dates to the 4th century BC, remains on view today in Londons Freud Museum, and its name Lekythos remains in our vocabulary as lecithin, from the Greek for egg-yolk (23
, 24)
. The graceful, spread-winged goddess is shown in pursuit of a beautiful youth with a lyre in his hand. The legend is that of Eo and Tithonus, a handsome mortal beloved by Eo. The goddess was so enamored of the young prince of Athens that she asked Zeus to make Tithonus immortal. He did, but she failed to ask Zeus to prevent Tithonus from aging. As time went on—as the fates wound down the string of life—he did indeed turn into a paltry thing: He aged, dried, and shrunk to the size of a cricket. And thats why crickets chirp at dawn.
Over the years, the legend has been iterated in poetry, music, and the visual arts; as our lifespan increases, each telling is more poignant. A version pertinent to modern biology was written in 1860 by Alfred Lord Tennyson. The poet has Tithonus pleading with Eo at dawns early light:
Its clear that what rickety-crickety Tithonus needed was a pill that would not only make him immortal but also keep him young enough to mix his nature (as it were) with Eos. If only he had been around to hear the news from Cal Tech! Shrunken to insect stature, what would Tithonus not have given for a mutated mth gene, for that mRNA peptide library, for that pill from Pasadena?
AFTER MANY A SUMMER DIES THE SWAN
But wait. Pasadena? Tennyson? Tithonus? I seem to have heard this song before. It turns out that one of the best-known works of longevity fiction is actually set in Pasadena: Aldous Huxleys "After Many a Summer Dies the Swan" (1939). Huxley, grandson of the great Darwinist, Thomas Henry Huxley, took the title from the opening lines of Tennysons "Tithonus."
The action of the Huxley novel takes place a short "motor-car ride" north of Los Angeles. On this as-yet undeveloped site, a boorish tycoon has built a large mansion (half the San Simeon of Hearst, half the Huntington Library) that houses valuable, ancient manuscripts. An English scholar is sent to look into a sheaf of books and manuscripts that the mogul has acquired from an English earl; these date back over 300 years. The tycoon has hired a certain Dr. Obispo (sic) to inject him with an extract that will prolong his life. The extract is prepared from the intestinal flora of carp, whose life expectancy far exceeds that of humans. Obispos biological experiments are based on the notions of Elie Metchnikoff, who won the Nobel Prize in 1908 for discovering phagocytosis. Metchnikoff suggested that we age because our intestinal bacteria generate toxic, oxygen-derived metabolites of fatty alcohols; these activate phagocytes of all stripes: macrophages and microphages (read neutrophils) and "neuronophages" (read glial cells). Dr. Obispo tests the effects of feeding carp intestines to mice: "The effect on the mice had been immediate and significant. Senescence had been halted, even reversed. They were younger at eighteen months than they had ever been" (26)
, just like Guarentess starved mice or Benzers fruit flies.
The locale also rings a bell. It seems that Huxleys fictional mogul is the chief supporter of an equally fictional university, Tarzana U, about to be erected near that monumental archive of manuscripts. The founder of Tarzana, Dr. Mulge, brags to his donor that
The Athens of the twentieth century is on the point of emerging here in the Los Angeles Metropolitan area. I want Tarzana to be its Parthenon [for] Art, Philosophy, Science (27).
Tarzana seems to be the fictional stand-in for Cal Tech; in 1939, Huxley was living in Los Angeles and experimenting with hallucinogens that might spur the imagination. The seminal spirit of Cal Tech was George Ellery Hale, an astronomer and the first director of the Mount Wilson Observatory. The real Dean Hale foresaw the future development of his Parthenon in Pasadena:
No creative work, whether in engineering or in art, in literature or in science, has been the work of a man devoid of the imaginative faculty (28).
Aldous Huxley would have been pleased that the California Institute of Technology is within a stones throw of the Huntington Library, where from time to time is displayed a copy of The Ellesmere Chaucer, acquired by Henry Huntington in 1917 from the Third Earl of Ellesmere, whose family had owned it for 300 years. Huxleys Dr. Obispo might have been pleased were he to have learned that nowadays, we, too, link aging to oxygen-derived free radicals. Indeed, we have experimental evidence that not only secretin but also other gastrointestinal hormones such as VIP and gastrin share G-protein-linked receptors with ligands involved in phagocytosis, immunity, and that gene for longevity in the fly (2
, 29
, 30)
. Who would have thought it?
Well, William Blake, for one, in his poem, "The Fly":
We have learned much about the life of flies and men, about Methuselah and Sun, and about other genes for "Time, Love, and Memory" (32)
from the wise man who put the fruit fly on the map of Pasadena forever: Seymour Benzer (October 15, 1921–November 30, 2007). He, too, has become his admirers.
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FOOTNOTES
The opinions expressed in editorials, essays, letters to the editor, and other articles comprising the Up Front section are those of the authors and do not necessarily reflect the opinions of FASEB or its constituent societies. The FASEB Journal welcomes all points of view and many voices. We look forward to hearing these in the form of op-ed pieces and/or letters from its readers addressed to journals{at}faseb.org.
REFERENCES
. Proc. Nat. Acad. Sci. USA 92,2283-2287.Related Articles
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