POKE THE POUNDS AWAY

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POKE THE POUNDS AWAY

• By
• WB
• CHEMISTRY 51
• OCTOBER 9, 2006

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ABSTRACT

• Ghrelin is known as the hunger hormone which
  triggers eating. Alarmed by the growing
  population of obese Americans, professors Eric
  Zorrilla and Kim Janda made an experiment on male
  rats aimed at curbing the release of ghrelin
  hormone. This experiment resulted to the
  so-called anti- obesity vaccine a vaccine
  that elicits antibodies that recognize active
  ghrelin.

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INTRODUCTION

• About 1/3 of the worlds population is
  overweight and
• America leads the world in obesity housing 23
  of the worlds obese population

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ROAD TO DISCOVERY

• This concern raised an alarm. In-depth
  researches and experiments followed thru with the
  aim of curbing obesity.
• Masayasu Kojima of Kurume University in Japan
  discovered ghrelin back in 1999.

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• Cytos Biotechnology in Schlieren, Switzerland
  probed into the subject further by conducting
  Phase I/II study on 112 obese patients.
• Recently, Eric Zorrilla, an assistant professor
  of neurosciences and Kim Janda, a chemistry
  professor, made their own research to look
  further into the subject.

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What is ghrelin?

• The "hunger hormone" known as ghrelin (GH), is a
  peptide (a protein), formed of 28 amino acids.

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• The word "ghrelin" comes from Hindi, and it means
  growth.
• Ghrelin cells namely excrete growth hormone,
  receptors of which have been found in the
  stomach, heart, lungs, pancreas and fat tissue.
  GH is an anabolic hormone that is essential for
  normal linear growth and has important metabolic
  effects throughout life.

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How does ghrelin work?

• The hormone is released by the stomach and
  intestines after a meal, in proportion to how
  many calories -- and, importantly, what kind of
  nutrients -- are eaten.
• It then wends its way to a small corner of the
  brain called the arcuate nucleus. This center
  serves as a telegraph desk, relaying chemical
  signals of hunger and satiety deeper into the
  mind, and helping stimulate the secretion of
  hormones from the pituitary gland as needed.

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What is the experiment all about?

• Professors Eric Zorilla and Kim Janda of Scripps
  Research Institute, developed a vaccine that will
  elicit antibodies that recognize active ghrelin.

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• The vaccine was injected into male rats.

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• The vaccine-induced antibodies sequestered the
  ghrelin secreted by the rats when they had not
  eaten.
• It thereby reduced the ability of ghrelin to
  reach the brain where it acts.

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• According to Professors Zorrilla and Janda, the
  rats injected with anti-obesity vaccine had
  less weight gain with their normal diet as
  opposed to those rats which were not immunized.

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PROS

• The vaccine may have the real potential to
  reduce, if not prevent, yo-yo dieting
• The vaccine causes less weight gain from normal
  diet and
• The most recent vaccine developed shows longer
  duration of efficacy as opposed to previous
  ghrelin vaccine.

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CONS

• The vaccines potential importance is unclear
  since it was tested on rodents
• Long-term ghrelin inhibition could cause diet
  regulation problems and
• Administering the vaccine may have serious
  ethical concerns since the effects of an active
  vaccine are irreversible.

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CONCLUSION

• Anti-obesity vaccine is a promising
  breakthrough to curtail obesity. However,
  further probing has to be done. Indeed, the
  experiment has to take real subjects (human) into
  consideration but in the process, it has to
  address ethical dilemma and strike a balance
  between would-be effects vis-à-vis foreseen
  outcome of immunization.

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REFERENCES

• http//www.aheartylife.com/2006/08/05/obesity-vacc
  ine-against-ghrelin/
• http//www.medicalnewstoday.com/medicalnews.php?ne
  wsid48471nfidmnf
• http//english.pravda.ru/world/americas/18-05-2006
  /80550-US_obesity-0
• http//en.wikipedia.org/wiki/Ghrelin
• http//origin.www.nature.com/nrd/journal/v5/n5/fig
  _tab/nrd2037_T1.html
• http//www.1stvitality.com/health/slimming/240203_
  ghrelin_appetite.htm
• http//www.healthscout.com/healthcentral.asp?page
  newsdetailap408id508470

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