Showing posts with label theology and bioethics. Show all posts
Showing posts with label theology and bioethics. Show all posts

Wednesday, March 13, 2013

Enhancing Healthy Kids: A Warning, But Who's Listening?

The American Academy of Neurology (AAN) has just issued new guidelines calling on doctors to stop prescribing cognitive-enhancing drugs to healthy kids.

Drugs like Ritalin and Adderal are widely used, not just by adults and university students, but increasingly by children, and not just those who are appropriately diagnosed as experience difficulites with attention or focus, such as Attention Deficit Disorder. 

PHOTO: Ritalin SR (a brand-name sustained-release formulation of methylphenidate, from Wikimedia, 16 June 2006, created by Sponge. 

Perviously, the AAN raised concerns drug enhancement by adults.  It concluded that there is no moral basis for objecting, provided that the patient is acting autonomously in requesting the prescription.  But when it comes to prescribing for healthy children, the AAN report makes this claim:  "Pediatric neuroenhancement remains a particularly unsettled and value-laden practice, often without appropriate goals or justification."  

The Report notes that enhancing children is fundamentally different from enhancing adults.  For doctors, it raises concerns for "the fiduciary responsibility of physicians caring for children, the special integrity of the doctor–child–parent relationship, the vulnerability of children to various forms of coercion, distributive justice in school settings, and the moral obligation of physicians to prevent misuse of medication."

Based on these concerns, the AAN Report advises that "the prescription of neuroenhancements is inadvisable because of numerous social, developmental, and professional integrity issues."

The primary objection raised by the AAN is that children lack the competency to act as autonomous moral agents.  If they were competent, then their request for enhancement would be honored.  Sure, children can be coerced, manipulated, confused, and ambivalent about their needs.  Kind of like the rest of us. 

Whether age brings moral competence is a good question.  But perhaps what this report shows us once again is that when secular bioethics meets enhancement technology, about all it can say is this: If you want it and if you can prove your competence, you can have it. 

The AAN report, “Pediatric neuroenhancement: Ethical, legal,social, andneurodevelopmental implications,” is published in the March 13, 2013 issue of Neurology.

Thursday, March 22, 2012

Stem Cell Update: Important Research Breakthrough

Another important step has just been taken toward achieving the medical promise of stem cell research. For the first time, researchers at the Max Planck Institute for Molecular Biomedicine in Münster, Germany, have reprogrammed skin cells directly into multipotent stem cells.

Over the past five years, stem cell researchers have learned how to induce or reprogram skin cells to become pluripotent stem cells—cells capable of becoming any type of cell in the body. The result: induced pluripotent stem cells or iPSCs. Scientists have also discovered how to reprogram cells to become precursor or progenitor cells. Precursor cells have a much narrower range of potential for development. They are able to become one very specific type of cell in the body.

Expanding on previous work, the latest breakthrough achieves a kind of “goldilocks” or just-right level. Working with mice, the team led by Hans Schöler discovered how to reprogram fully differentiated skin cells into neuronal stem cells (NSC)s. Unlike pluripotent cells, NSCs are far more suitable for clinical use. And now, with this breakthrough, the Max Plank Institute team has learned how to reprogram or induce NSCs or iNSCs.

And unlike precursor or progenitor cells, iNSCs are capable of multiplying and diffentiating once they are implanted. When researchers implanted their iNSCs into mouse brains, iNSCs generated new cells that began to take on some of the characteristics of ordinary developing brain cells.

Caption: This is an immunofluorescence microscopy image of the induced neural stem cells (iNSCs) using antibodies against two neural stem cell markers SSEA1 (red color) and Olig2 (green color). Credit: MPI for Molecular Biomedicine

The field of stem cell research has faced many obstacles, some moral and some medical. The main moral objection is that the prime source of human pluripotent cells is the human embryo, and many object to the destruction of the embryo for medical purposes. One of the medical challenges is that implanted cells are likely to be rejected by the immune system, much as transplanted organs are rejected unless immunosuppressant drugs are given.

Unless, of course, the source of the cells is from the patient’s own body. That’s why this achievement is important. If this technique can be applied to human cells—and there’s no reason to think it can’t—then someday it may be possible to take a small sample of cells from a patient’s skin, convert them to iNSCs, and then implant them in the patient’s brain to repair damage from disease or injury.

Not only does the iNSC discovery use the patient’s own cells as the source. It also by-passes the pluripotent stage. That fact should help researchers avoid creating cancer or other problems.

According to Schöler, "pluripotent stem cells exhibit such a high degree of plasticity that under the wrong circumstances they may form tumours instead of regenerating a tissue or an organ."

"Our research shows that reprogramming somatic cells does not require passing through a pluripotent stage," Schöler said in a press release issued by the Max Plank Institute. "Thanks to this new approach, tissue regeneration is becoming a more streamlined—and safer—process."

The article, "Direct Reprogramming of Fibroblasts into Neural Stem Cells by Defined Factors," appears in the March 22 issue of Cell Stem Cell.

Tuesday, November 1, 2011

Resveratrol and Human Enhancement

The debate over human enhancement may just have entered a new phase. Resveratrol, the natural compound found in red wine, has now been shown to improve the metabolism of human beings. While the word "enhancement" does not appear in the published report, the research will almost certainly be read by many as evidence that the use of resveratrol enhances human health and may even increase the human lifespan.

In the more prosaic language of the report, the news is simply this: Resveratrol, the natural compound found in red wine, has now been shown to improve the metabolism of human beings.

In the 2 November 2011 issue of the journal Cell Metabolism, researchers in the Netherlands and Switzerland report that a 30-day course of resveratrol brought about significant improvement in the basic metabolic functions of obese men.

Research using animals has shown that resveratrol can have a number of benefits related to how the body uses energy. In some species, resveratrol has been shown to increase average longevity. In other experiments involving lab animals, a reduction of 30-50% in calorie intake below what the animals normally eat has been shown to benefit the metabolism and extend the lifespan. Others studies show that resveratrol seems to mimic the effects of calorie restriction.

Now come hints that resveratrol may have some of these same effects on human beings. In the Cell Metabolism article, researchers report that the men who received the 150mg/day dose of resveratrol showed a number of changes that mimic what happens with calorie reduction. 150mg is about 100 times the amount of resveratrol found in an ordinary glass of red wine.

One of the researchers, Patrick Schrauwen, commented on the study in a press release issued by Maastricht University in the Netherlands: “We saw a lot of small effects, but consistently pointing in a good direction of improved metabolic health.” The study was concluded after 30 days, and so long-term benefits or side-effects are not known.

In particular, no one knows whether resveratrol has the capacity to extend the human lifespan. But the positive results published on 2 November will surely intensify the debate over the effects and the ethics of resveratrol.

In this study, resveratrol was administered to men who were obese but otherwise healthy. One way some bioethicists distinguish between morally legitimate “therapy” and morally questionable biomedical “enhancement” is by insisting that medicine must stick to treating those with disease. It is unethical, these bioethicists argue, to “enhance” people by using medicine to benefit those who are not sick. Their views are challenged by others who believe that technology should be used for human enhancement.

While this study may have observed that moral limit of treating only those with a “disease,” there is little reason to believe that the metabolic benefits of resveratrol are limited to those who are obese. On the contrary, there is every reason to think that this study will be used by advocates of human enhancement. In particular they will see this as the best evidence yet that resveratrol can be used to extend the human lifespan.

My prediction is that this study will encourage more widespread use of resveratrol. Most who use it will be seeking some form of enhancement if not an increase in longevity.

The article, “Calorie restriction-like effects of 30 days of resveratrol (resVidaTM) supplementation on energy metabolism and metabolic profile in obese humans,” appears in the 2 Nov 2011 issue of Cell Metabolism, where it is available free to the public.

Friday, December 12, 2008

Dignitas Personae: Theology and Stem Cell Research

The long-awaited Vatican Instruction, Dignitas Personae, was released today. It is a complex document that will require careful analysis. For instance, compared to Donum Vitae, does Dignitas assert that an embryo is a person from conception, something that Donum avoided asserting? Both agree, of course, that the embryo must be respected morally as a person from conception.

Two points stand out for me on my first reading. They concern Germline Modification and Altered Nuclear Transfer.

Regarding human germline modification, Dignitas is decidedly more negative compared to other recent Vatican statements. According to Dignitas, gene therapy that affects only the patient--"somatic cell gene therapy"--is acceptable. However,

The moral evaluation of germ line cell therapy is different. Whatever genetic modifications are effected on the germ cells of a person will be transmitted to any potential offspring. Because the risks connected to any genetic manipulation are considerable and as yet not fully controllable, in the present state of research, it is not morally permissible to act in a way that may cause possible harm to the resulting progeny. In the hypothesis of gene therapy on the embryo, it needs to be added that this only takes place in the context of in vitro fertilization and thus runs up against all the ethical objections to such procedures. For these reasons, therefore, it must be stated that, in its current state, germ line cell therapy in all its forms is morally illicit.

This rather bleak statement is in clear contrast to a previous Vatican statement entitled "Communion and Stewardship: Human Persons Created in the Image of God," which stated:

Germ line genetic engineering with a therapeutic goal in man would in itself be acceptable were it not for the fact that is it is hard to imagine how this could be achieved without disproportionate risks especially in the first experimental stage, such as the huge loss of embryos and the incidence of mishaps, and without the use of reproductive techniques. A possible alternative would be the use of gene therapy in the stem cells that produce a man’s sperm, whereby he can beget healthy offspring with his own seed by means of the conjugal act.

What is remarkable about the "Communion and Stewardship" text is that the statement actually suggested a way forward for research that could lead to a Vatican-approved approach to human germline modification. What is even more remarkable is that because of recent advances in stem cell research, especially induced pluripotency, research someday may actually achieve success in meeting the previously stated Vatican requirements. Now, however, Dignitas seems to back away from the previous endorsement. For more on this, see my recent book, Design and Destiny, from MIT Press.

The second issue has to do with "Altered Nuclear Transfer" (ANT), a provocative proposal that was seriously debated by the US President's Council on Bioethics. The idea, as championed by Bill Hurlbut, a member of the Council, was to create an "artifact" that might provide embryonic stem cells without being an embryo. The hope of the advocates of ANT was that those who oppose embryo research would see ANT as creating something that was decidely not an embryo and therefore an acceptable object for research. Now the Vatican has raised doubts:

These proposals [explicitly including ANT] have been met with questions of both a scientific and an ethical nature regarding above all the ontological status of the "product” obtained in this way. Until these doubts have been clarified, the statement of the Encyclical Evangelium vitae needs to be kept in mind: “what is at stake is so important that, from the standpoint of moral obligation, the mere probability that a human person is involved would suffice to justify an absolutely clear prohibition of any intervention aimed at killing a human embryo”.

If the Vatican has its doubts, then it's not clear who ANT is meant to placate. Sure, some individuals will say they oppose embryo research but find ANT acceptable. But the big institutional player, the Vatican, has just raised serious doubts and then asserted that doubt means no. As usual, the National Catholic Reporter provides a nice discussion of these issues, including quotes from Hurlbut.

Personally, I have never been a supporter of ANT, but I feel sorry for its advocates, who made the proposal in good faith in hopes that individuals and institutions would see it as a way around the difficult question of the use of the human embryo in research.