Insects that heal
Maneka Sanjay Gandhi
Human beings have used insects as medicine in different human cultures throughout the world, but very little research was done to convert local use into proven, standardised medicine. Entomotherapy is a branch of science that uses insects for medicine. The rise of antibiotic resistant infections has forced pharmaceutical research into looking for new resources. Many insects, used in alternative medicine, are now being tested for mainstream medical products. FDA, for instance, recently approved the flu vaccine, Flublok, which is derived from cells taken from the ovaries of the fall armyworm moth.
One insect alone, the honey bee, provides honey, pollen, royal jelly, propolis, and an anti-inflammatory peptide melittin. Honey is applied to the skin to treat scar tissue, rashes and burns, and as an eye poultice, for digestive problems and as a general health restorative.
It is taken hot to treat colds, coughs, laryngitis, tuberculosis, throat infections and lung diseases.
Apitoxin (honey bee venom) is applied through direct stings to relieve arthritis, rheumatism, polyneuritis and asthma. Propolis, used by bees as a hive insulator and sealant, is said to have antibiotic, anaesthetic, and anti-inflammatory properties. Royal jelly is used to treat anaemia, ulcers, arteriosclerosis and hypertension. Bee pollen is eaten as a health restorative.
Over a thousand protein families have been identified in the saliva of blood-feeding insects; these may provide useful drugs such as anticoagulants, vasodilators, antihistamines and anaesthetics.
Here are some lesser known insects who are used in human medicine:
The University of Miami is researching the use of the venom of the South American devil tree ant in rheumatoid arthritis. Half the patients were injected with venom extract. The other half with placebos. Those who received the venom derivative showed dramatic reduction in the number and intensity of inflamed joints, and marked increases in their freedom of motion. Patients who received the placebo showed no improvement. A US patent is pending on the chemical.
Many native healers use ants. Black mountain ant extracts dilate blood vessels that supply the penis. Red harvester ant venom was used to cure rheumatism, arthritis and poliomyelitis. The South American tree ant, Pseudomyrmex sp, commonly called as the Samsum ant’s venom can reduce inflammation, inhibit tumour growth and treat liver ailments.
Even 3,000 years ago the mandibles of soldier ants were used as stitches. The ant was agitated, and when it opened its jaws, it was placed around the wound to be stitched and the mouth allowed to close. The ant’s body was then pinched away, leaving the head holding the wound together.
Several African cultures use poultices made from ground grasshoppers as pain relievers for migraines. Neurologists hypothesise that grasshopper toxins stimulate the human central nervous system, and dilate blood vessels, increasing circulation. Powdered, sun-dried, grasshopper is turned into a tea for the treatment of asthma and hepatitis.
Across Southeast Asia, healers have capitalised on blister beetles’ healing powers since ancient times. Also known as ‘Spanish Fly’, the beetles represent humankind’s first remedy for erectile dysfunction. Blister beetle secretions reduce burning pain sensations commonly associated with urinary tract infections, insect bites, kidney problems, and burns.
Blister beetles secrete cantharidin, which is effective in treating severe viral infections, because it prevents viral cell reproduction, and may be useful in treatment of cancerous tumours resistant to radiation and chemotherapy. A number of research papers have been published confirming that cantharidin has multiple effects on cancer cells.
Emerging science suggests that silkworm extracts may have benefits, as dietary supplements, for patients with heart disease and circulatory disorders. Preliminary studies indicate that they reduce serum cholesterol, and dissolve vascular plaque. Boiled silkworm pupae have been used by Chinese medicine to treat apoplexy, bronchitis, convulsions, and frequent urination. A bacteria that lives in the digestive system of silkworms contains a substance known as serrapeptase. This substance appears to offer pain relief for people with back injuries. Studies are underway to see if they can also help with sports injuries.
Traditional Asian practitioners use centipedes to treat tetanus, seizures, and convulsions. Centipedes are dried, ground into a paste, and applied topically to sores and carbuncles.
Ayurveda uses termites, and their mounds, for ulcers, rheumatic diseases, anaemia, and pain. In Africa, termites are used in asthma, bronchitis, inﬂuenza, whooping cough.
Spider silk is ideal to use in skin grafts, or ligament implants, because it is one of the strongest known natural fibres, and triggers little immune response. It may also be used to make fine sutures for stitching nerves, or eyes, to heal with little scarring.
The jatropha leaf miner, a moth who feeds on the jatropha plant, is an example of an insect considered a pest who has medicinal value. The larvae of the insect are harvested, boiled, and mashed into a paste which is administered topically and is said to induce lactation, reduce fever, and soothe gastrointestinal tracts.
In southwestern Nigeria, an infected foot is treated by smearing and rubbing mashed mole crickets on it.
Locusts are eaten in post childbirth anaemia, for lung diseases, asthma and chronic cough.
The May beetle is used as a remedy for anaemia and rheumatism. The peanut beetle for asthma, arthritis, tuberculosis, and the palm beetle for earache.
Cicadas are crushed and applied for migraine headaches and ear infection.
The red velvet mite is eaten for treatment of urogenital disorders, and paralysis.
A mass of boiled mealybugs was ingested to alleviate the effects of poisonous mushrooms and other fungi, or diarrhoea, to clean the teeth, and in the treatment of caries.
In the heads of cockroaches are chemical compounds that can kill Escherichia coli (E Coli) and Methicillin-resistant Staphylococcus aureus (MRSA), two harmful bacteria that are resistant to most drugs. It was discovered that tissues, taken from the brains and nervous system of the insects, killed off over 90 per cent of MRSA infections and E coli.
Scientists from the Institute for Biomedical Research, Barcelona, have carried out successful in vitro tests, using wasp venom, to kill cancer cells. Wasp venom contains Polybia MPI (from venom of the wasp polybiapaulista), which shows anti tumour activity and kills only cancer cells, leaving the healthy cells around it.
Studies on caterpillar venom show that cecropins, which are a group of peptides isolated from the caterpillar blood of the giant silk moth hyalophoracecropia, have anti-microbial activity, and have been used as a potent anti-cancer agent against a variety of tumour cell lines. Cecropins are active against several mammalian lymphomas and leukaemia, and may offer novel strategies for bladder cancer treatment.
In 1993, Margatoxin was synthesised from the venom of the Central American bark scorpion. Patented by Merck, it has the potential to prevent bypass graft failure. Scorpion venom extract has been shown to be able to detect and spotlight cancer cells under a special light used during surgery.
All these insects are being killed by the millions everyday as pests. Unless we take action to protect and develop our environment sustainably, and get rid of pesticides/herbicides and poisons that kill them and us, the window of chance for the discovery of new medicinal agents will be closed forever.