Celebrating World Wildlife Day
By Irish Research Council
Posted: 3 April, 2016
Arthropods (i.e. bugs with legs) are arguably the most diverse and intriguing group of animals the world has ever seen. They live everywhere around us: in our cities, in our homes and even in our beds, representing over 80% of all animal diversity on Earth.
Although over a million species of arthropods have already been described by scientists, it is estimated that at least 2 million species still remain unknown. In Ireland alone, over 12,000 species of bugs have been recorded, including 1,400 moths, 2,000 ground beetles and 400 spiders.
Arthropods are essential to the ecological balance of our planet and to the survival of mankind: they eat our rubbish, fertilise our land and pollinise our crops. For the past 500 million years, arthropods have been at the forefront of a war for survival, colonising virtually every niche an ecosystem can offer. To survive, arthropods have evolved amazing mechanisms: some have antifreeze flowing through their body; some have venom, poison or silk; others have flight and amazing camouflage.
It is only recently that scientists have started to investigate arthropods as a novel source of compounds, with potential applications in pharmacology, medicine and engineering. In the past decade, painkillers, anti-cancer treatments, anti-inflammatory agents, anti-bacterial gels and nano-scaffolding have been developed based on substances produced by arthropods!
But how much more is there to discover? In the case of spiders, virtually all of the 40,000 species known worldwide possess a pair of fangs and venom glands used to kill prey and deter predators. Venom is a complex cocktail containing hundreds of bioactive components, including potent toxins. Spider neurotoxins can shut down the central nervous system of their prey, leading to respiratory or cardiac arrest. Hemotoxins have the ability to make the blood thinner or thicker, leading to organ failures and haemolysis. Necrotoxins can penetrate cell membranes, causing living tissue to die.
These toxins, once rearranged, can become powerful tools for the treatment of diseases. It is already asserted that each species of spider possess its own cocktail of toxins, giving unique properties to its venom. Worldwide, this represents at least 40,000 toxic blends that might hold treatments for diseases crippling millions of people. What if venom was not just species-specific but population-specific? Or maybe even individual-specific, just like our fingerprints? That would mean millions of bioactive combinations are there to be explored i.e. a huge biodiverse pharmacy waiting to be harvested!
Less than 100 species worldwide have been investigated for the therapeutic potential of their venom. Here at NUI Galway, we decided to start at our doorstep: for the first time the venom of an Irish spider is being investigated for its anti-cancer properties… and the prospect of turning local bugs into the pharmacy of the future is really exciting!
Dr Michel Dugon is an Irish Research Council Fellow working on the rapid evolution of spider venom and its potential therapeutic applications at NUI Galway.