Scientists invent implantable slimming aid

Genetic regulatory circuit monitors blood fat

The research group headed by ETH-Zurich professor Martin Fussenegger from the Department of Biosystems Science and Engineering in Basel has now developed an early warning system and treatment: an implantable genetic circuit mainly composed of human gene components. On the one hand, it constantly monitors the circulating fat levels in the blood. On the other hand, it has a feedback function and forms a messenger substance in response to excessively high blood-fat levels that conveys a sense of satiety to the body.

In order to construct this highly complex regulatory circuit, the biotechnologists skilfully combined different genes that produce particular proteins and reaction steps. They implanted the construct in human cells, which they then inserted into tiny capsules.

The researchers studied obese mice that had been fed fatty food. After the capsules with the gene regulatory circuit had been implanted in the animals and intervened due to the excessive levels, the obese mice stopped eating and their bodyweight dropped noticeably as a result. As the blood-fat levels also returned to normal, the regulatory circuit stopped producing the satiety signal.

“Instead of placing the mice on a diet to achieve weight loss, we kept giving the animals as much high-calorie food as they could eat,” stresses Fussenegger. The animals ate less because the implant signalised a feeling of satiety to them. Mice that received normal animal feed with a five-per-cent fat content did not lose any weight or reduce their intake of food, says the biotechnologist.

Sensor for different dietary fats

One major advantage of the new synthetic regulatory circuit is the fact that it is not only able to measure one sort of fat, but rather several saturated and unsaturated animal and vegetable fats that are ingested with food at once. However, this development cannot simply be transferred to humans. It will take many years to develop a suitable product. Nonetheless, Fussenegger can certainly envisage that one day obese people with a body mass index of way over thirty could have such a gene network implanted to help them lose weight. Fussenegger sees the development as a possible alternative to surgical interventions such as liposuction or gastric bands. “The advantage of our implant would be that it can be used without such invasive interventions.” Another merit: instead of intervening in the progression of a disease that is difficult to regulate, it has a preventive effect and exploits the natural human satiety mechanism.

This gene network is one of the most complex that Fussenegger and his team have constructed to date and was made possible thanks to the biotechnologist’s years of experience in the field. It is not the first time he and his team have succeeded in constructing such a complex feedback regulatory circuit: a number of years ago, they produced an implant that can also be used to combat gout via a feedback regulatory circuit.

Cloning

Human cloning is the creation of a genetically identical copy of a human. It does not refer to monozygotic multiple births or the reproduction of humans/animals cells or tissue. The ethics of cloning is an extremely controversial issue. The term is generally used to refer to artificial human cloning; human clones in the form of identical twins are commonplace, with their cloning occurring during the natural process of reproduction.

There are two commonly discussed types of human cloning:

•  therapeutic cloning 
• reproductive cloning. 

 Therapeutic cloning involves cloning cells from an adult for use in medicine and transplants, and is an active area of research. Reproductive cloning would involve making cloned humans, for couples wanting to have a child, but cannot naturally.

A third type of cloning called replacement cloning is a theoretical possibility, and would be a combination of therapeutic and reproductive cloning. Replacement cloning would entail the replacement of an extensively damaged, failed, or failing body through cloning followed by whole or partial brain transplant or harvesting the internal organs of the clone.

Pros
When it comes to animal cloning, the strongest argument that you are likely to hear is the fact that we can use this process to save several animal species from extinction. Similarly, the advocates of human cloning put forth the argument that it will help to solve the infertility problems in humans. They also state that the process of organ transplantation will become much easier if human cloning is developed to its full potential. By resorting to therapeutic cloning the doctors will be able to replace damaged tissues and organs in the human body, and treat various diseases and disorders with ease. Similarly, genetic modification will have an all new meaning as parents will be able to choose the traits that they would like to see in their child.

Cons
While the advocates of human cloning are armed with several reasons to support their stand, the critics don't seem to be impressed at all. The critics are of the opinion that creating a human clone would mean interfering with the natural process of procreation. At the same time, one needs to also ponder upon the fact that if genes are modified to create smarter human beings by means of cloning, what would happen to the average humans who are not the products of this process. Critics also cite the fact that cloning will result in a huge divide among people, and clones will not be subjected to equal treatment. In a world full of divides on the basis of race and caste, we can't afford to have one more reason to add to the differences. The religious heads of different religious sects are of the opinion that human cloning will put forth man as the creator - which would be like challenging the authority of the supreme entity. At the same time, the critics also cite that more than 90 percent of the attempts to clone mammals have met with failure in the past.

When it comes to therapeutic cloning, the pros seem to have a slight advantage over cons. There also exist concepts such as replacement cloning - wherein a clone of previously living person can be created, and persistence cloning - wherein the cloned body will be created to do away with the process of aging. However, these concepts are still on the paper, and it's a bit too early to talk about them.

 

The Risks

 

• Inefficient Process
• Genetic Anomalies
• Trouble During Growth
• Contracting Telomeres
• Social and Ethical Issues

 

Benefits

• Infertility Treatment: Human cloning could be a blessing for infertile couples, as reproductive cloning does not involve the fusion of the sex cells.
• Treating Diseases: As already discussed, therapeutic cloning can be used to treat a number of degenerative diseases like those of the nervous system, spinal cord injury and organ failure. Also who knows, it could also be used to regenerate whole limbs. This would provide a life changing line of treatment for amputees.
• Replacing Defective Genes: Defective genes would cause sickness in an individual, however healthy a lifestyle he leads. Advances in human cloning will help him to replace the defective genes with healthy ones
• Cosmetic Treatment: Relieving individuals of the diseases that are caused due to plastic or cosmetic surgery, is another human cloning benefit.