The sharks' immune systems are different from humans' and shark derivatives are now under intensive study. Squalamine, derived from sharks, is a unique compound that kills a variety of bacteria, fungi, and parasites. Shark cartilage has been used in alternative medicine as an anti-cancer and anti-AIDS compound because sharks apparently do not suffer from cancer. Mainstream medical researchers, who once thought the shark products were merely the "patent medicines" of human "sharks", are now investigating those marine carnivorous fishes' derivatives for their potential in the treatment of a number of human ills.
Enrollment is now underway by Genaera Corporation, a biopharmaceutical headquartered in Plymouth Meeting, Pennsylvania, according to the FDANews Drug Pipeline Alert, to test the efficacy of squalamine in treating "wet" age-related macular degeneration (AMD.Macular degeneration affects approximately 20 percent of Americans aged 65 and older and is a leading cause of blindness. The macular is the center of the retina, the light receptor in the eye. The first symptoms usually are loss of central visual acuity or visual distortion in one eye. The wet type of macular degeneration is caused by the growth of abnormal blood vessels behind the macula. The abnormal blood vessels tend to hemorrhage or leak, resulting in the formation of scar tissue .No medical therapy, thus far, has proven effective.
Squalamine is the leading anti-angiogenic drug being developed to treat AMD. Angiogenesis is a word that comes from combining the two Greek words angio, meaning "blood vessel," and genesis, meaning "beginning." Angiogenesis is the creation of tiny new blood vessels. Normally, angiogenesis is a healthy process. New blood vessels develop, for instance, to help your body heal cuts and other wounds. But with AMD the same process creates new, very small blood vessels that damage the macula in the eye. Antiangiogenesis treatment is the use of drugs or other substances to stop the development of macula damaging new blood vessels. Such treatments are believed to also be applicable to certain tumors. Without a blood supply, tumors can't grow.
Incidentally, while shark skin is not pleasant to touch, the oil from its liver oil is a rich source of vitamin A and is now being used in cosmetic lubricating creams and lotions.
For further information about Genaera's AMD research, check http://www.genaera.com/about.html