Medicine of the Future

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Walters 1 James C Walters Dr. Rand Rhetoric 102 2 May 2008 Medicine of the Future Modern medicine has changed our life expectancies greatly and, in effect, the course of history. As programs like Barbara Walters “Live to 150: Can . . . Can You Do It?” begin to enter the mainstream, we begin to wonder: “How long can we really walk this planet?” No longer is the question “Would I really want to live past 100 years old?” just an entertaining quandary; modern medical breakthroughs—eking eerily close to science fiction’s wildest fantasies—allow us to be part of a world we never thought possible. Mechanical limbs, cryogenic freezing, and chemicals that mimic the fountain of youth are a few of the more quixotic developments that are currently being undertaken. If medicine progresses at the rate it is going now, you may no longer ask “How long can I live?” but— “How long do I want to live?”—which has Frankensteinian overtones and questions the ethical boundaries of science. Of course, this is just speculation, but our technological capabilities have expanded exponentially and are seemingly endless in theory and application. Furthermore, breakthroughs in medicine are taking place constantly. Implantation of mechanical organs, revolutionary cellular biology, organ farming, and even regrowing organs are the more realistic aims for projects that are currently under development. Regenerative medicine, in accordance with modern stem cell experimentation, is one of the new fascinating methods for increasing the human life span, but at the moment it may hold the most promise. It is exciting to be

Walters 2 alive in this era, not only because of the abundance of technology, but also because this technology directly affects our own time on this planet.

Understanding Regeneration “Individual survival in the face of environmental insults and entropic processes requires a mechanism that can maintain the functional integrity of tissues. That mechanism is regeneration” (Stocum 1). Without the ability to regenerate certain parts in our bodies, we would not survive for very long. As one of the “great masters of regenerative biology,” Richard J. Goss asserts: “If there were no regeneration there could be no life” (qtd. in Stocum 1). Evidently, our bodies go through regeneration constantly —regenerating cells and even various types of tissues—what David L. Stocum denotes as “homeostatic regeneration,” or maintenance. Stocum also mentions that we lose (in terms of survival) as individuals, but win as a species (through reproduction) (1). Sherwin Nuland, writer of the book How We Die, would argue that death is a necessary and inevitable aspect of human life. Best put by the blind poet, Homer, in his epic poem, The Iliad: “As the generation of leaves, so is that of humanity. The wind scatters the leaves on the ground, but the live timber burgeons with leaves again in the season of spring returning. So one generation of men will grow while another dies” (6.146-50). Thus, death should not be feared because it is a necessary part of human life. David L. Stocum, however, makes the distinction that nature provides us with fibrosis, which “patches a wound with scar tissue whose structure is quite different from the original tissue structure” (1). In order to discover what this difference was, I interviewed Dr. Ed Devlin, Professor of Biology at Hampden-Sydney College, who explained: “[Scar tissue] doesn’t

Walters 3 have as much flexibility or as much elastic fiber [as normal skin]. . . . So even though they’re [the scar tissue cells] made up of the same material that you see in the rest of the body, their orientation and organization can make them a little bit less flexible.” Thus, the integrity of scar tissue is not quite as strong as regular tissue and, therefore, less effective. On the one hand, we may not be able to regenerate another organ or limb, like some amphibians, but on the other hand, Mother Nature has not left us defenseless. As Stocum explains: “Repair by fibrosis maintains the overall integrity of the tissue or organ, but at the expense of reducing its functional capacity” (1). In short, it’s like fixing a hole in a metal pipe with duct tape (probably more effective than duct tape). According to Stocum, regeneration takes place at three levels: molecular, cellular, and the tissue level (4). This explains why we can regenerate necessary bodily fluids, like blood, but why we can not regenerate whole organs. An example of the molecular level would be adjustment of molecules after protein synthesis (4). In terms of cellular regeneration, Stocum adds: “a single carrot cell can regenerate a whole carrot” (4). Unfortunately, tissue regeneration is not as simple, requiring three prerequisites: mitotically competent cells (“cells that have the receptors and signal transduction pathways to respond to a regeneration-permissive environment”), the “[injured] environment of the tissue must contain the necessary signals to promote the proliferation and differentiation of these cells in an organized way,” and last, circumstances that inhibit cell regeneration must not be present (4). Put simply, tissues must have cells that can communicate well with other cells, enough of the injured area must remain intact, and there can be no extenuating circumstances that would otherwise inhibit regeneration.

Walters 4 The salamander is a master at the art of limb regeneration; it can regrow a limb as many times as is needed; therefore, it is our paradigm for regeneration techniques: When the tiny salamander limb is amputated, blood vessels in the remaining stump contract quickly, so bleeding is limited, and a layer of skin cells rapidly covers the surface of the amputation site. During the first few days after injury, this so-called wound epidermis transforms into a layer of signaling cells called the apical epithelial cap (AEC), which is indispensable for successful regeneration. In the meantime, fibroblasts break free from the connective tissue meshwork and migrate across the amputation surface to meet at the center of the wound. There they proliferate to form a blastema—an aggregation of stem like cells that will serve as progenitors for the new limb. (Muneoka, Han, and Gardiner 57) According to Muneoka, Han, and Gardiner, writers for Scientific American: “A loose arrangement of cells called fibroblasts holds all these internal tissues [skeleton, muscles, ligaments, tendons, nerves, and blood vessels] together and gives the limb its shape” (57). But when a limb or other large part of our body is amputated, fibroblasts do not migrate to the affected site like they do in salamanders. The biggest question, in regards to salamanders, that plagues our mind is “How do their regenerating parts know where to go?” According to Dr. Devlin, when the salamander limb is severed, the cells in the affected area dedifferentiate, becoming more like stem cells. Dr. Devlin mentions that the salamander’s body pumps ions to the “stump,” which “generates a small electric current that helps orient the cells for regeneration. Moreover, Dr. Devlin adds that scientists have conducted experiments by hooking small batteries and sending a current to the limb, which helps speed up the process of regeneration.

Walters 5 Certain organs and tissues regenerate constantly in the body. Dr. Devlin explains: There’s quite a few parts of the body that regenerate. The body has a number of stem cell populations . . . about every two weeks you replace all of the epidermis [skin]. . . . The liver’s a great organ of regeneration. Every time a student partakes in drinking, and takes in various types of toxic substances, the liver works very hard to detoxify that stuff, and a lot of cells are killed off; but they have the ability to regenerate themselves. The lining of the gut . . . regenerates itself; in about two weeks, it will form a whole new gut. In addition to that, things you wouldn’t think of as being regenerative tissues . . . bones . . . even though the cells don’t regenerate, a lot of the tissue regenerates. Indeed, many types of organs are constantly regenerating. I think it’s more intriguing that the bones, even though the cells don’t regenerate, regenerate over time. Interestingly enough, one part of the human body is known to hold regenerative capabilities: the fingertip. Evidently, regenerating the fingertip only requires the person to “clean the wound” and cover it with a “simple dressing.” According to Muneoka, Han, and Gardiner: “If allowed to heal naturally, the fingertip restores its contour, fingerprint and sensation and undergoes a varying degree of lengthening” (61). The same phenomenon is recorded in mice. Further, Lee Spievak, a man who accidentally cut off an inch of his middle finger with a model airplane propeller, regenerated his entire finger back; incidentally, Spievak used a protein powder that may have helped his finger regenerate (Muneoka, Han, and Gardiner 60).

Recent Breakthroughs in Regenerative Medicine

Walters 6 The potential for this new form of medicine is seemingly boundless in its application regarding wound treatment as well as slowing the overall aging process. In a more lucrative approach, the market for this new medical technology is ubiquitous; everyone wants to remain youthful—and in years to come—no one will (have to) live without body parts, ranging from the spinal cord to the kidney—as long as they can afford it. These kinds of developments are daunting in their complexity, yet much simpler than most surgical procedures in their physical applications. In fact, Dr. Stephen Richardson, University of Manchester, England, regarding spinal trouble, asserts: “What we envision is a one-stop shop for treatment. You’d come in, get these cells implanted into your spine, and end up with regenerated new tissue. And that would be it, for life. . . . The patient could go home the same day as the procedure” (qtd. in Weiss n. pag.). Furthermore, regenerative medicine would put a less dismal overtone on organ transplantation. Dr. Anthony Atala, chairman of the urology department at Wake Forest and president of the North American Tissue Engineering and Regenerative Medicine International Society, explains that patients wouldn’t have to wait “for someone to die so they can live” (qtd. in Parson F5). “A more immediate goal is to improve upon a multitude of smaller therapies: transplantable valves for ailing hearts, cell-and-gel preparations for crushed nerves, injections of skeletal muscle cells for urinary continence . . .” (Parson F5). Interestingly enough, these aforementioned projects are already being tested and applied: “That same year [1999] he [Atala] inserted his bladder scaffolds into the first of seven children with spina bifida. . . . ‘All seven continue to do well. . . . The oldest of the new bladders has functioned for more than six years’” (qtd. in Parson F5).

Walters 7 According to the U.S. Department of Health and Human Services, the number of American adults suffering with disabilities or “limitation(s) in usual activities due to chronic conditions” is 34.4 million; that’s 11.8 percent of America, not including children. The Disability Insurance Trust Fund Expenditures for 2007 was 95,865 million. The number of Americans who have been diagnosed with heart disease is 24.1 million; that’s 11 percent of America. Heart disease is ranked as the number one cause of death in the United States; it caused 652,486 deaths by April 1st 2008. The number of people on the waiting list for organ transplants is 98,796. Americans with disabilities may become a thing of the past; imagine 34.4 million more people not only being able to work, but not drawing welfare. Moreover, if regenerative medicine reaches its full potential, heart disease will no longer be an issue because you would be able to either regrow clogged arteries or even an entire heart! Unfortunately, I can already hear what the lethargic, obese portion of America will be saying: “I don’t need to exercise honey: I’ll just get a new heart. I’ve already been through two already.” When regenerative medicine comes into full-swing, all these statistics will change dramatically; incidentally, Dr. Devlin believes that this kind of technology (at least for a while) will be accessible mainly to people who can afford it. Many burn victims suffer the loss of their family, home, and skin. Victims of third-degree burns are branded by fire; in many cases they lose their dignity because of their physical appearance and suffer from constant physical torment. Luckily, tissueengineered skin is a reality for regenerative medicine, which could provide a gleam of hope for third-degree burn victims. Tissue engineered skin has been developed because autographs (removing skin from another part of the victim’s body) cause much “pain,

Walters 8 infection, and scarring” (Priya, Jungvid, and Kumar 105). Interestingly enough, as S. Geetha Priya, Hans Jungvid, and Ashok Kumar, biological engineers, write: “The application of tissue engineering progress in medicine is discussed according to the origin of germinal layers during embryonic development. Thus engineered tissues could reduce the need for organ replacements” (105). That might reduce a hefty chunk of the 98 thousand people on the organ transplant waiting list. Another problem with human autographs is that they are costly and “limited and therefore cannot be used in case of extensive third-degree burns” (105). Unfortunately, as of now, there are problematic issues with tissue-engineered skin: “Tissue-engineered skin is one of the most advanced tissue constructs, yet it lacks several important functions; hair follicles, sebaceous glands, sweat glands, and dendritic cells” (Priya, Jungvid, and Kumar n. pag.). Dr. Devlin argues that you could probably get by without hair follicles and sebaceous glands. As for sweat glands, Devlin asserts that if the skin is going to an area of the body that does not regulate body temperature, such as the armpit, sweat glands would probably not be necessary. Regarding dendritic cells, Dr. Devlin reveals that those are the cells associated with pressure and nerve cells, so you do not necessarily need those, depending, once again, on what part of the body is being addressed. Evidently, the tissue-engineered skin of modern medicine (2008) has some problems to work out until it is reliable. Nonetheless, it does have the advantage of being less painful than normal skin grafts, potentially more effective and faster, and it does not require a donor. As Priya, Jungvid, and Kumar remind us, skin: “protects against toxins and microorganisms in the environment and serves to prevent dehydration of all non-aquatic animals” (119). So it goes without saying —skin is very important to humankind. Furthermore, there exists no current engineered

Walters 9 skin that “completely replicates normal uninjured skin,” but “As engineered skin substitutes improve in quality, they will become more similar to native skin autographs” (119). Moreover, the exciting research for regenerative medicine is expanding and economizing; since businesses are racing for the finish, it will not be long until this technology reaches the mainstream. Dr. Devlin notes that private companies do a lot to further the research in biomedicine, as well as the non-profit organizations and the federal government. In a 2007 issue of Drug Week, Geoff MacKay, CEO of Organogenesis, Inc., remarks: “Our field has now transitioned from visionary science fiction, into exciting, proven science. In order to ensure the technology reaches patients, regenerative medicine companies need to evolve into successful commercial entities” (“Gene Therapy” 295). Ya gotta love capitalism. There are, nonetheless, some moral concerns regarding this research because a great deal of the experimentation is done with embryonic stem cells. “The era of human embryonic stem cells dawned in 1998 in James Thomson’s lab at the University of Wisconsin” (Cookson 4). Since the discovery of embryonic stem cells in Thomson’s lab, regenerative medicine was born and with it the new, highly-controversial era of wasting stem cells to save lives; however, organizations like The Coalition for the Advancement of Medical Research (CAMR) are working to sidestep these ethical landmines. CAMR’s website explains that the organization is “dedicated to being a national, collective voice on Capitol Hill and in the media for those who believe that regenerative medicine, including embryonic stem cell research, holds the key to providing American families with hope for the future” (n. pag.). Personally, I believe that, as long as no one is being

Walters 10 hurt—since the fetus is already dead—there is no moral-conflict in the use of aborted fetuses (especially fetuses that are aborted during the first trimester) as a means of progressing scientifically and potentially saving millions of lives. Dr. Devlin explains: “Mostly they don’t use the later aborted fetuses though because if your wanting to get a stem cell population, you don’t want a population that has started to go down the developmental pathways . . .” Fortunately, science may not even have to meddle with this particular ethical dilemma. Science is sidestepping these ethical landmines at an unstoppable speed. Advanced Cell Technology, Inc. has discovered an interesting way to deal with the stem cell controversy: cloning embryonic stem cell derivatives (“Regenerative Medicine” 303). But much more fascinating, as Joseph K. Vetter writes, in an section entitled “Medical Breakthroughs ’08,” with the equally fitting title “Stem Cell Stunner”: “[A] Japanese team led by Shinya Yamanaka, demonstrated that with a little coaxing, the iPS cells [induced pluripotent stem cells], could transform themselves into different types of human tissue” (145). This explains why Reader’s Digest properly dubs this finding “Breakthrough of the Year.” The significance of this experiment is tremendous in terms of regenerative medicine because these cells were created using skin cells rather than embryonic stem cells; therefore, these cells could be used for regenerating all sorts of tissue, and, theoretically, scientists could produce an “unlimited supply” (Vetter 145). This breakthrough brings with it endless possibilities for healthcare. Regarding the locating of adult stem cells, Dr. Atala chuckles: “The irony of the whole field was that people were looking for cells according to the properties of the tissues they resided in . . . but they were overlooking the tissue’s regenerative cells, the cells that grew best, because

Walters 11 they were immature and didn’t yet have those properties” (qtd. in Parson F5). According to Vetter: “The iPS cells even have an advantage over embryonic: Since they’re derived form the patient’s own cells, there’s no risk of rejection” (145). Put best by Dr. Alan Retik, chief of urology at Children’s Hospital Boston: “Using a patient’s own tissue in this fashion for self-repair is ‘inevitable. . . . It has so many advantages over conventional surgical methods that ultimately it will be the preferred method’” (Parson F5). Even more exciting: “[The Japanese team tried to manipulate] heart cells. Just 12 days after mixing a sample of iPS cells with a cocktail of proteins in a petri dish, the scientists watched as clumps of newly formed cardiac cells started beating like a human heart” (145). This is perhaps the most interesting and exhilarating news of the year; if scientists can create heart cells, and the heart is the most important organ, second to the brain, in terms of survival, then that only leaves the brain, and we could, theoretically, live—forever. Once again, this brings up the ethical ruminations left by Mary Shelly after reading her novel, Frankenstein.

Conclusion Regenerative medicine and other modern medical breakthroughs may provide a— once unfathomable—extension to the human life span. While regenerative medicine is certainly the most feasible and hopeful type of futuristic medicine, others exist. Resveratrol, a phytoalexin found in substances such as red wine, has recently been studied because of its beneficial effects on heart disease, immunity, cancer, and other medical uses (Shazib n. pag.).

Walters 12 Creeping even more toward science-fiction based ideology, the age of the cyborg looms ever nearer. In fact, a new development, an artificial lung, is now under development, thus further reducing the need for organ transplantation. Robert Bartlett, professor emeritus of surgery at the University of Michigan, claims that his “BioLung” relies on the heart to pump oxygen and blood flow throughout the body (DiCesare 147). Unfortunately for Dr. Bartlett and his team, it might appeal more to people to grow a new lung than to insert a mechanical one inside their body. On the other hand, “The device can even remain in place following a transplant, until the donor lungs are fully operational,” (DiCesare 147) which would mean that there would still be use for this technology in surgery. Biologist J. Craig Venter, PhD and founder of the Institute for Genomic Research, has recently decoded his own genome (Tyranski 148). This is an interesting development because it can mean a quantum leap forward in preventative medicine. Dr. Venter found he was predisposed to Alzheimer’s, diabetes, blindness, and heart disease. When asked if he was worried, Dr. Venter replied: “Not really. I’ve tried to change my diet and get more exercise. And I started taking a statin to lower my cholesterol” (qtd. in Tyranski 148). Dr. Venter is an excellent example of what identification of the various genomic predispositions can help us do; even if we can not change our susceptibility to a particular ailment, we can do our best to prepare for it and possibly prevent it entirely. As Dr. David Stocum argues: “Regenerative medicine is on the cusp of becoming a millennial revolution. . . . Twenty-five years ago, patients paralyzed as a result of spinal cord injuries were told . . . that there was no hope. Like other dogmas, this one, too, has crumbled under the weight of scientific advance” (Stocum 425-426). Regenerative

Walters 13 medicine may very well be the answer to all our modern medical problems, at least until the next millennia when people are concerned with living to 1000 years. Dr. Devlin believes both cybernetic limbs/organs and regenerative technology will play a major role in the next phase of medicine—as well as preventive medicine. I can see it already: Tonight on ABC, Barbara Walters “Live to 1500 . . . Can You Do It?” However, Dr. Devlin dispels these myths: “Every time [the cells of our body] divide, a little end of the chromosome, called the telomere, is chopped off. As the cells divide, that telomere gets shorter and shorter and that cuts into genes that are useful to the organ. . . . Also, DNA is damaged over time . . . those damage sites accumulate over time . . . eventually those damage sites go into parts of the DNA that code for the cell cycle.” As we all know, when the cell cycle gets out of control, cancer develops. But Dr. Devlin also mentioned that, in evolutionary terms, we are only supposed to live to about 30-40 years, so who knows what technology holds in store for us.

Walters 14 Works Cited CAMR. Coalition for the Advancement of Medical Research. CAMR: The Coalition for the Advancement of Medical Research. 2001. 14 Apr. 2008 <http://www.camradvocacy.org>. Cookson, Clive. "Era of 'regenerative medicine'.(WORLD NEWS)." The Financial Times (Nov 21, 2007): 4. Academic OneFile. Gale. Hampden-Sydney College. 15 Apr. 2008 <http://find.galegroup.com>. Devlin, Ed. Personal Interview. 17 Apr. 2008. DiCesare, Ann. “An Artificial Lung.” Reader’s Digest. Mar. 2008: 147. “Gene Therapy; CEO of World’s First Profitable Regenerative Medicine Company, ORGANOGENESIS, Details Path to Profitability for the Regenerative Medicine Field.” Drug Week. 25 May 2007: 290. LexisNexis Academic. LexisNexis. Hampden-Sydney College. 14 Apr. 2008 <http://www.lexisnexis.com>. Homer. The Iliad. Chicago: Chicago, 1951. Muneoka, Ken, Manjong Han, and David M. Gardiner. “Regrowing Human Limbs.” Scientific American. Apr. 2008: 56-63. Parson, Ann. "With Special Scaffold, a Tissue Engineer Sows Cells and Grows Organs." The New York Times (July 11, 2006): F5(L). Academic OneFile. Gale. Hampden-Sydney College. 15 Apr. 2008 <http://find.galegroup.com>. Priya, S. Geetha, Hans Jungvid, and Ashok Kumar. "Skin tissue engineering for tissue

Walters 15 repair and regeneration." Tissue Engineering, Part B: Reviews 14.1 (March 2008): 105(14). Academic OneFile. Gale. Hampden-Sydney College. 16 Apr. 2008 <http://find.galegroup.com>. “Regenerative Medicine; Advanced Cell Technology Platform Yields Over 140 Cell Types from Human Embryonic Stem Cells.” Biotech Business Week. 14 Apr. 2008: 303. LexisNexis Academic. LexisNexis. Hampden-Sydney College. 15 Apr. 2008 <http://www.lexisnexis.com>. Shazib Pervaiz, "Resveratrol", in AccessScience@McGraw-Hill, <http://www.accessscience.com>. Stocum, David L. Regenerative Biology and Medicine. Canada: Elsevier, 2006. Tyranski, Kathryn M. “Mapping Our Own Genes.” Reader’s Digest. Mar. 2008: 148. U.S. Department of Health and Human Services. National Center for Health Statistics. Fast Stats A to Z. 31 Mar. 2008. 15 Apr. 2008 <http://www.fedstats.gov>. Vetter, Joseph K. “Stem Cell Stunner.” Reader’s Digest. Mar. 2008: 145. Weiss, Michael J. “7 Back Pain Breakthroughs: Are you hurting? Here’s help: Stem Cells to the Rescue.” Reader’s Digest. July 2007. 14 Apr. 2008 <http://www.rd.com>.

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