University of Queensland researchers have designed a novel tarantula venom mini-protein that can potentially relieve severe pain without addiction.
Dr Christina Schroeder from UQ's Institute for Molecular Bioscience said the current opioid crisis around the world meant urgent alternatives to morphine and morphine-like drugs, such as fentanyl and oxycodone, were desperately needed.
"Although opioids are effective in producing pain relief, they come with unwanted side-effects like nausea, constipation and the risk of addiction, placing a huge burden on society," Dr Schroeder said.
"Our study found that a mini-protein in tarantula venom from the Chinese bird spider, known as Huwentoxin-IV, binds to pain receptors in the body.
"By using a three-pronged approach in our drug design that incorporates the mini-protein, its receptor and the surrounding membrane from the spider venom, we've altered this mini-protein resulting in greater potency and specificity for specific pain receptors.
"This ensures that just the right amount of the mini-protein attaches itself to the receptor and the cell membrane surrounding the pain receptors."
Dr Schroeder said the mini-protein had been tested in mouse models and shown to work effectively.
"Our findings could potentially lead to an alternative method of treating pain without the side-effects and reduce many individuals' reliance on opioids for pain relief," she said.
CHEOPS has reached its next milestone: Following extensive tests in Earth's orbit, some of which the mission team was forced to carry out from home due to the coronavirus crisis, the space telescope has been declared ready for science. CHEOPS stands for ''CHaracterising ExOPlanet Satellite'', and has the purpose of investigating known exoplanets to determine, among other things, whether they have conditions that are hospitable to life.
CHEOPS is a joint mission by the European Space Agency (ESA) and Switzerland, under the leadership of the University of Bern in collaboration with the University of Geneva (UNIGE). After almost three months of extensive testing, with part of it in the midst of the lockdown to contain the coronavirus, on Wednesday, March 25, 2020, ESA declared the CHEOPS space telescope ready for science. With this achievement, ESA has handed over the responsibility to operate CHEOPS to the mission consortium, which consists of scientists and engineers from approximately 30 institutions in 11 European countries.
The successful completion of the test phase took place in very challenging times, with essentially all the mission team being required to work from home towards the end of the phase. "The completion of the test phase was only possible with the full commitment of all the participants, and because the mission has an operational control system that is largely automated, allowing commands to be sent and data to be received from home," explains Willy Benz, Professor of Astrophysics at the University of Bern and Principal Investigator of the CHEOPS mission.
The team began by focusing on the evaluation of the photometric performance of the space telescope. CHEOPS has been conceptualized as a device of exceptional precision capable of detecting exoplanets the size of planet Earth. "The most critical test was in the precise measurement of the brightness of a star to a variance of 0.002% (20 parts-per-million)," explains Willy Benz. This precision is required so as to clearly recognize the dimming caused by the passage of an Earth-sized planet in front of a Sun-like star (an event known as a "transit," which can last several hours).
CHEOPS was also required to demonstrate its ability to maintain this degree of precision for up to two days. The space telescope satisfied all required criteria with flying colours.
The team observed other stars, including some known to host planets (these are called exoplanets). CHEOPS focused on the planetary system HD 93396 which is in the Sextans constellation, some 320 light years away from Earth. This system consists of a giant exoplanet called KELT-11b, which was discovered in 2016 to orbit this star in 4.7 days. The star is almost three times the size of the sun.
The team chose this particular system because the star is so big that the planet takes a long time to pass in front of it: in fact, almost eight hours. "This gave CHEOPS the opportunity to demonstrate its ability to capture long transit events otherwise difficult to observe from the ground, as the 'astronomical' part of the night for ground-based astronomy usually takes less than eight hours," explains Didier Queloz, professor at the Astronomy Department of the Faculty of Science at the University of Geneva and spokesperson of the CHEOPS Science Team.
The transit of KELT-11b measured by CHEOPS enabled determining the size of the exoplanet. It has a diameter of 181,600 km, which CHEOPS is able to measure with an accuracy of 4'290 km. The diameter of the Earth, in comparison, is only approximately 12,700 km, while that of Jupiter -- the biggest planet in our solar system -- is 139,900 km. Exoplanet KELT-11b is therefore bigger than Jupiter, but its mass is five times lower, which means it has an extremely low density: "It would float on water in a big-enough swimming pool," says David Ehrenreich, CHEOPS Mission Scientist from the University of Geneva.
The limited density is attributed to the close proximity of the planet to its star. Benz explains that the measurements by CHEOPS are five times more accurate than those from Earth. "That gives us a foretaste for what we can achieve with CHEOPS over the months and years to come," continues Benz.
University of Bern. "CHEOPS space telescope ready for scientific operation." ScienceDaily. ScienceDaily, 16 April 2020. <www.sciencedaily.com/releases/2020/04/200416114541.htm>.