Coral Reefs Can Save Lives

Coral reefs are home to many organisms that have evolved unique ways of defending themselves from predators, parasites, and competitors. Some of these organisms, such as corals, sponges, sea squirts, cone snails, and algae, produce chemical compounds that can deter or harm other creatures that try to attack them or invade their space. These compounds are called secondary metabolites. They often have complex structures and biological activities that make them attractive candidates for drug discovery.

Scientists have been studying these coral reef secondary metabolites for decades, and have discovered many promising compounds that have been isolated for medicine. Some of these compounds have already been approved as drugs, while others are still in various stages of testing and development. Here are some of the medical uses of coral reef-derived compounds:

Treatments for cardiovascular diseases, skin cancer, ulcers, and leukemia.
- One of the most successful compounds is Ziconotide, which is based on the venom of cone snails. It's a powerful painkiller that blocks nerve signals in the spinal cord, and is used to treat patients with severe chronic pain that cannot be relieved by other drugs.
- Eribulin is derived from a sponge compound called halichondrin. It is an anticancer drug that interferes with cell division and causes cancer cells to die. Eribulin is thus involved in the treatment of patients with advanced breast cancer and liposarcoma.
- Vidarabine is taken from another sponge compound called spongothymidine and is used to treat viral infections.
- Cytarabine is also derived from spongouridine and is used to treat leukemia.
- Trabectedin comes from a sea squirt compound called ecteinascidin. It's used to treat soft tissue sarcoma and ovarian cancer.
Reducing inflammation. The modulation of the immune system and reduction of inflammation is important in controlling many diseases such as arthritis, asthma, and inflammatory bowel disease.
- In this context, pseudopterosin is used to enhance wound healing. It has its roots in the soft coral Pseudopterogorgia elisabethae
- Manoalide comes from a sponge called Luffariella variabilis.It can inhibit the enzyme phospholipase, which is involved in inflammation and pain.
Killing viruses. Compounds that can inhibit or kill viruses that cause e.g. herpes, hepatitis, HIV, and influenza.
- Bryostatin comes from the bryozoan Bugula neritina. It can activate latent HIV-infected cells and make them more susceptible to antiretroviral drugs.
- Kahalalide, from a sea slug Elysia rufescens, can inhibit the replication of hepatitis C.
Relaxing muscles and spasm/contraction prevention
- Brevetoxin, which is derived from a dinoflagellate called Karenia brevis, can bind to sodium channels in nerve cells and cause muscle relaxation.
- Tetrodotoxin the highly toxic compound from pufferfish (Takifugu rubripes) liver at very low doses, it has therapeutic effects for treating various types of pain, especially those related to cancer, nerve damage, or internal organs. It works by blocking sodium channels in nerve cells, which reduces the transmission of pain signals.
In addition to the drugs that have already been approved or tested, there are many more compounds that have been identified from coral reef organisms that have potential applications for human health. Examples:
- Curacin from the cyanobacterium Lyngbya majuscula, has anticancer properties by inhibiting tubulin polymerization.
- Palau’amine, derived from the sponge Stylissa carteri, has antibacterial properties through the inhibition of DNA synthesis.
- Dolastatin, from the sea hare Dolabella auricularia has anticancer properties
- Discodermolide from the sponge Discodermia dissoluta also has anticancer properties.
- Bengamide from Jaspis sp. sponges has antiviral properties.

In conclusion, coral reefs are important sources of new medicines being developed to treat a variety of illnesses. However the threats from climate change, pollution, and overfishing (especially with cyanide or bombs) threaten the existence of reefs. If the coral reefs disappear we will loose an untold number of unthought-of drugs. It is thus essential to protect and conserve coral reefs for the sake of human health and well-being.