NASA’s SpaceX Dragon Resupply Mission Launches – Cargo Includes Water Bears, Squid, Solar Panels

The latest SpaceX Dragon resupply spacecraft is on its way to the International Space Station after launching at 1:29 p.m. EDT Thursday from NASA’s Kennedy Space Center in Florida, bearing more than 7,300 pounds of science experiments, new solar arrays, and other cargo.

The spacecraft launched on a Falcon 9 rocket from Launch Pad 39A at Kennedy. It is scheduled to autonomously dock at the space station around 5 a.m. Saturday, June 5, and remain at the station for about a month. Coverage of arrival will begin at 3:30 a.m. on NASA Television, the agency’s website, and the NASA app.

This 22nd contracted resupply mission for SpaceX will deliver the new ISS Roll-out Solar Arrays (iROSA) to the space station in the trunk of the Dragon spacecraft. After the Dragon docks to the space station’s Harmony module, the robotic Canadarm2 will extract the arrays and astronauts will install them during spacewalks planned for June 16 and 20.

Among the science experiments Dragon is delivering to the space station are:

These immature bobtail squid (Euprymna scolopes) are part of UMAMI, an investigation that examines whether space alters the symbiotic relationship between the squid and the bacterium Vibrio fischeri. Credit: Jamie S. Foster, University of Florida

Symbiotic squid and microbes in microgravity

The Understanding of Microgravity on Animal-Microbe Interactions (UMAMI) study examines the effects of spaceflight on the molecular and chemical interactions between beneficial microbes and their animal hosts. Microbes play a significant role in the normal development of animal tissues and in maintaining human health. “Animals, including humans, rely on our microbes to maintain a healthy digestive and immune system,” says UMAMI principal investigator Jamie Foster. “We do not fully understand how spaceflight alters these beneficial interactions. The UMAMI experiment uses a glow-in-the-dark bobtail squid to address these important issues in animal health.”

The bobtail squid, Euprymna scolopes, is an animal model that is used to study symbiotic relationships between two species. This investigation helps determine whether spaceflight alters the mutually beneficial relationship, which could support development of protective measures and mitigation to preserve astronaut health on long-duration space missions. The work also could lead to a better understanding of the complex interactions between animals and beneficial microbes, including new and novel pathways that microbes use to communicate with animal tissues. Such knowledge could help identify ways to protect and enhance these relationships for better human health and well-being on Earth as well.

Cell Science-04 flies tardigrades, or water bears, to the space station for a study seeking to identify the genes involved in its adaptation and survival in high stress environments. Credit: Thomas Boothby, University of Wyoming

Water bears take on space

Tardigrades, known as water bears due to their appearance under a microscope and common habitat in water, are tiny creatures that tolerate environments more extreme than most life forms can. That makes them a model organism for studying biological survival under extreme conditions on Earth and in space. In addition, researchers have sequenced the genome of the tardigrade Hypsibius exemplaris and developed methods for measuring how different environmental conditions affect tardigrade gene expression. Cell Science-04 characterizes the molecular biology of short-term and multigenerational survival of water bears, identifying the genes involved in adaptation and survival in high stress environments.

The results could advance understanding of the stress factors affecting humans in space and support development of countermeasures. “Spaceflight can be a really challenging environment for organisms, including humans, who have evolved to the conditions on Earth,” says principal investigator Thomas Boothby. “One of the things we are really keen to do is understand how tardigrades are surviving and reproducing in these environments and whether we can learn anything about the tricks that they are using and adapt them to safeguard astronauts.”

A cotton seedling for the TICTOC investigation prepared for flight. TICTOC studies how root system structure affects cotton plant resilience, water-use efficiency, and carbon sequestration during the critical phase of seedling establishment. Credit: Simon Gilroy, University of Wisconsin-Madison

Producing tougher cotton

Cotton plants that overexpress a certain gene show increased resistance to stressors, such as drought, and yield 20% more cotton fiber than plants without that characteristic under certain stress conditions. This stress resistance has been tentatively linked to having an enhanced root system that can tap into a larger volume of soil for water and nutrients. Targeting Improved Cotton Through On-orbit Cultivation (TICTOC) studies how root system structure affects plant resilience, water-use efficiency, and carbon sequestration during the critical phase of seedling establishment. Root growth patterns depend upon gravity, and TICTOC could help define which environmental factors and genes control root development in the absence of gravity.

Cotton is used in a variety of consumer products from clothing to bed sheets and coffee filters, but the effects of its production include significant water use and intensive use of agricultural chemicals. “We are hoping to reveal features of root system formation that can be targeted by breeders and scientists to improve characteristics such as drought resistance or nutrient uptake, both key factors in the environmental impacts of modern agriculture,” says principal investigator Simon Gilroy. Improved understanding of cotton root systems and associated gene expression could enable development of more robust cotton plants and reduce water and pesticide use.

On-the-spot ultrasound

Butterfly IQ Ultrasound demonstrates use of a portable ultrasound in conjunction with a mobile computing device in microgravity. The investigation collects crew feedback on ease of handling and quality of the ultrasound images, including image acquisition, display, and storage.

“This type of commercial off-the-shelf technology could provide important medical capabilities for future exploration missions beyond low-Earth orbit, where immediate ground support is not available,” says Kadambari Suri, integration manager for the Butterfly iQ Technology Demonstration “The investigation also examines how effective just-in-time instructions are for autonomous use of the device by the crew.” The technology also has potential applications for medical care in remote and isolated settings on Earth.

Developing better robot drivers

Pilote, an investigation from the ESA (European Space Agency) and the Centre National d’Etudes Spatiales (CNES), tests the effectiveness of remote operation of robotic arms and space vehicles using virtual reality and interfaces based on haptics, or simulated touch and motion. Testing of the ergonomics for controlling robotic arms and spacecraft must be performed in microgravity, because designs from Earth-based testing would use ergonomic principles that do not fit conditions experienced on a spacecraft in orbit. Pilote compares existing and new technologies, including those recently developed for teleoperation and others used to pilot the Canadarm2 and Soyuz spacecraft. The investigation also compares astronaut performance on the ground and during long-duration space missions. Results could help optimize the ergonomics of workstations on the space station and future space vehicles for missions to the Moon and Mars.

Protecting kidneys in space and on Earth

Some crew members exhibit an increased susceptibility to kidney stones during flight, which could affect their health and the success of the mission. The Kidney Cells-02 investigation uses a 3D kidney cell model (or tissue chip) to study the effects of microgravity on the formation of microcrystals that can lead to kidney stones. It is part of the Tissue Chips in Space initiative, a partnership between the ISS U.S. National Laboratory and the National Institutes of Health’s National Center for Advancing Translational Sciences (NCATS) to analyze the effects of microgravity on human health and translate that to improvements on Earth. This investigation could reveal critical pathways of kidney disease development and progression, potentially leading to therapies to treat and prevent kidney stones for astronauts and for the 1 in 10 people on Earth who develop them.

“With this study, we hope to identify biomarkers or ‘signatures’ of cellular changes that occur during the formation of kidney stones,” says principal investigator Ed Kelly. “This may lead to novel therapeutic interventions. The rationale for conducting this study on the space station is that the microcrystals behave in a manner like what happens in our own kidneys, meaning they stay suspended in the kidney chip tubes and do not sink to the bottom, like they do in labs on Earth.”

This image shows the planned configuration of six iROSA solar arrays intended to augment power on the International Space Station. The roll-up arrays arrive on the SpaceX-22 resupply mission. Credit: NASA/Johnson Space Center/Boeing

Bonus power

New solar panels headed to station are made up of compact sections that roll open like a long rug. The ISS Roll-out Solar Arrays (iROSA) are based on a previous demonstration of roll-out panels performed on station. They are expected to provide an increase in energy available for research and station activities. NASA plans a total of six new arrays to augment the station’s power supply with the first pair launching on this flight. The Expedition 65 crew is scheduled to begin preparations for spacewalks to supplement the station’s existing rigid panels this summer. The same solar array technology is planned to power NASA’s Gateway, part of the Artemis program.

SpaceX’s Falcon 9 rocket is sending the company’s Dragon spacecraft, filled with more than 7,300 pounds of research, crew supplies and hardware to the space station to support expeditions 65 and 66.

These are just a few of the hundreds of investigations currently being conducted aboard the orbiting laboratory in the areas of biology and biotechnology, physical sciences, and Earth and space science. Advances in these areas will help keep astronauts healthy during long-duration space travel and demonstrate technologies for future human and robotic exploration beyond low-Earth orbit to the Moon and Mars through NASA’s Artemis program.

Important Global Health Problem Identified: Disease of the Smallest Heart Blood Vessels

Mechanisms of myocardial ischaemia, including the microvessels. Credit: European Heart Journal

For the first time, a prospective, international study has shown that chest pain caused by problems with the very small vessels supplying blood to the heart is an important health problem that increases the risk of heart attacks, stroke, and death due to cardiovascular reasons.

The study, which is published today (May 27, 2021) in the European Heart Journal^[1], recruited 686 patients from 14 institutions in seven countries on four continents^[2] between July 2015 and December 2018 to investigate microvascular angina (MVA). Until now, MVA was widely thought to be a benign disease that mainly occurs in women. However, the study showed that during one to two years of follow-up until December 2019, events such as stroke, heart attack and hospitalization for chest pain (angina) occurred in nearly 8% of patients each year. Men and women were almost equally affected and the prognosis was no different according to sex or ethnicity.

Until relatively recently, little was known about MVA and it can be difficult to diagnose, partly because diagnostic criteria were proposed only in 2018 by the COronary VAsomotor Disorders International Study (COVADIS) Group. Patients with MVA can experience chest pains similar to those of a heart attack and/or shortness of breath, which can lead to them being admitted to the hospital. However, standard tests, such as electrocardiograms (ECGs), angiograms and echocardiography, do not detect significant problems with heart rhythm or the main coronary arteries, meaning that MVA is often not diagnosed.

Only 5% of coronary arteries are visible by coronary angiography. Credit: European Heart Journal

First author of the study and member of the COVADIS Group, Professor Hiroaki Shimokawa, said: “Microvascular angina is an under-researched area, partly because no definite universal definition was available before the COVADIS definition and partly because cardiologists are mainly interested in the large coronary arteries but not the smaller vessels that are also part of the coronary circulation. The former are easily visible by coronary angiography, whereas the latter are not.

“Currently, many doctors are not aware of the importance of coronary microvascular dysfunction. As a result, many patients with MVA are misdiagnosed as having postmenopausal disorders or an imbalance of conscious and unconscious nervous system, for instance. However, previous research has suggested that the number of patients with MVA is three to four million in USA, which is equal to or greater than the number of patients with breast cancer, so it is an important global problem.”^[3]

Prof. Shimokawa, who is Vice Dean of the Graduate School at the International University of Health and Welfare (Narita, Japan) and Emeritus/Visiting Professor at the Graduate School of Medicine, Tohoku University (Sendai, Japan), and colleagues applied the COVADIS diagnostic criteria in the current study: 1) signs and symptoms suggesting reduced blood flow to the heart (myocardial ischaemia); 2) no evidence of the main coronary arteries being blocked; 3) objective evidence of myocardial ischaemia provided by non-invasive stress testing of the heart using ECGs or non-invasive imaging such as cardiac magnetic resonance; and 4) evidence of impaired coronary microvascular function showing, for instance, inability of the coronary arteries to increase blood flow under stress, heart microvascular spasms, indications of abnormal resistance to blood flow in the heart’s tiny blood vessels, or delayed flow in the arteries of the contrast agent used for angiograms, indicating increased resistance to blood flow in more distant vessels (known as “coronary slow flow”) but with no evidence of disease in the main coronary arteries.

During the follow-up period, there were 78 cases of death or hospitalization due to major cardiovascular problems such as heart attack and stroke, heart failure, or unstable angina (6.4% in men and 8.6% in women) – an annual incidence of 7.7% among all the patients in the study. Hospitalization for unstable angina was the commonest event.

Analysis showed that high blood pressure, previous history of coronary artery disease and stable angina were all important and independent predictors of these major cardiovascular events. Although Caucasians had a higher risk than Asians (annual incidences of 9.3% versus 4.5%), there was no significant difference between the two ethnic groups after adjustments were made for factors that could affect the results, such as age, sex, high blood pressure, diabetes, smoking etc. Women had significantly worse quality of life than men, although they had a similar long-term prognosis; the researchers say this could be due to the effect of female hormones on pain perception.

Prof. Shimokawa said: “Angina is usually thought to be caused mainly by narrowing of the large coronary arteries. However, even after treatment of these arteries with stents or bypass surgery, approximately 40% of patients will still experience chest pains, suggesting problems with microvascular dysfunction are very common. In addition, it has been recently and convincingly demonstrated that the treatment of the large coronary arteries with stent or bypass surgery alone does not significantly improve the long-term prognosis of patients with coronary artery disease, again suggesting the prognostic importance of coronary microvascular dysfunction.

“Our international study demonstrates the importance of coronary microvascular dysfunction in patients with MVA. Considering the fact that coronary microvascular dysfunction is involved not only in MVA but also in other forms of cardiovascular disease, including large coronary artery disease and myocardial disease, we believe clinicians should pay closer attention to it.”

The researchers say that the management and treatment of MVA represents a major unmet need and more research is needed. Patients are usually treated with drugs to prevent blood clotting, such as statins, angiotensin-converting enzyme (ACE) inhibitors or angiotensin receptor blockers (ARBs), or drugs to dilate blood vessels such as beta-blockers, calcium channel blockers, and nitrates.

Editor-in-Chief of the European Heart Journal, Filippo Crea, Professor of Cardiology and Director of the Department of Cardiovascular and Pneumological Sciences at the Catholic University of the Sacred Heart (Rome, Italy), is a co-author of the study. He said: “It can be estimated that in most European countries, 20,000-40,000 people per million of the population suffer from angina. Thus, the total number of angina patients is about 21 million in Europe. As several studies have shown that about 50% of angina patients do not have coronary narrowing, this means that about ten million people in Europe have angina caused by functional alterations in either the large or small coronary arteries or both. The situation is similar in Asia and US. This huge number of patients deserves to be carefully identified and treated. In addition, these data should stimulate the development of drugs that specifically target coronary microcirculation. Last but not least, these functional alterations are frequent not only in angina patients but also in those who present with myocardial infarction.”

Limitations of the study include the fact that it was an observational study with no reference group against which to compare results; there was a relatively small number of major cardiovascular events during the follow-up period, which may affect the statistical power of the study; the majority of these events were hospitalization for unstable angina; patients with obstructive coronary artery disease diagnosed by conventional or coronary computed angiography were excluded from the study; and there are no data on changes or adherence to medical therapy, or on symptoms or quality of life during the follow-up period.

Notes:

1. “Clinical characteristics and prognosis of patients with microvascular angina: an international and prospective cohort study by the Coronary Vasomotor Disorders International Study (COVADIS) Group”, by Hiroaki Shimokawa et al., 27 May 2021, European Heart Journal.
   DOI: 10.1093/eurheartj/ehab282
2. The following countries enrolled patients into the study: Japan (191 cases), the UK (171), Germany (109), the USA (88), Italy (59), Spain (51) and Australia (17).
3. “Ischemia and no obstructive coronary artery disease (INOCA). Developing evidence-based therapies and research agenda for the next decade,” by C. Noel Bairey Merz et al. Circulation. 2017;135:1075-1092.

Metamorphosis: The Fascinating Secrets of How Clownfish Earn Their Stripes

Amphiprion percula, a species of clownfish photographed in Kimbe Bay, Papua New Guinea. Credit: Tane Sinclair-Taylor

The distinctive white stripes in clownfish form at different rates depending on their sea anemone hosts, a PNAS study finds.

• Clownfish species develop their characteristic white stripes, or bars, during the process of metamorphosis
• Researchers have now discovered that the white bars form at different speeds depending on the sea anemone the clownfish live in
• Thyroid hormones, which are important for metamorphosis, control the speed the white bars form
• Levels of thyroid hormones are higher in clownfish that live in the giant carpet anemone compared to clownfish living in the magnificent sea anemone
• Clownfish living in the giant carpet anemone also show increased activity of duox, a gene involved in forming thyroid hormones

Charismatic clownfish, the coral reef fish made famous by the film Finding Nemo, are instantly recognizable by their white stripes. These stripes, which scientists call bars, appear as clownfish mature from larvae into adults in a process called metamorphosis, but how these distinctive patterns form has long remained a mystery.

Now, a new study has found that the speed at which these white bars form depends on the species of sea anemone in which the clownfish live. The scientists also discovered that thyroid hormones, which play a key role in metamorphosis, drive how quickly their stripes appear, through changes in the activity of a gene called duox.

“Metamorphosis is an important process for clownfish – it changes their appearance and also the environment they live in, as clownfish larvae leave life in the open ocean and settle in the reef,” said senior author Professor Vincent Laudet, who leads the Marine Eco-Evo-Devo Unit at the Okinawa Institute of Science and Technology Graduate University (OIST). “Understanding how metamorphosis changes depending on the sea anemone host can help us answer questions not only about how they adapt to these different environments, but also how they might be affected by other environmental pressures, like climate change.”

In the study, published on May 24th, 2021 in PNAS, a team of researchers from the Centre for Island Research and Environmental Observatory (CRIOBE) in France first surveyed the clownfish species, Amphiprion percula, in Kimbe Bay, Papua New Guinea.

The clownfish species, Amphiprion percula, relies on either the long-tentacled sea anemone, Heteractis magnifica (left) or the short-tentacled Stichodactyla gigantea (right) as its host. The sea anemones, armed with toxic stinging cells on their tentacles, protect clownfish from predators on the reef. The clownfish also protect the sea anemone from predators and provide nutrition and oxygenation to their host. Credit: Kina Hayashi

The clownfish there can live either in the magnificent sea anemone, Heteractis magnifica, or the more toxic giant carpet anemone, Stichodactyla gigantea.

During the survey, the team made a fascinating observation; the juvenile clownfish that lived in the giant carpet anemone gained their adult white bars faster than clownfish living in the magnificent sea anemone.

During metamorphosis, the clownfish, Amphiprion percula, turns a vibrant orange and develops three white bars in succession, from head to tail. The rate at which the bars form depends on the sea anemone that the clownfish live in. Clownfish living in the long-tentacled anemone, Heteractis magnifica, (left) have fewer stripes than clownfish of the same age and size living in the shorter, carpet-style anemone, Stichodactyla gigantea (right). The image shows the typical appearance of clownfish aged 150-200 days. Credit: Fiona Lee, Academia Sinica, Taiwan

“We were really interested in understanding not only why bar formation occurs faster or slower depending on the sea anemone, but also what drives these differences,” said first author Dr. Pauline Salis, a postdoctoral researcher at the Observatoire Océanologique de Banyuls-sur-Mer, Sorbonne Université Paris, who studies color patterning in coral reef fish.

In the lab, the team worked with the clownfish, Amphiprion ocellaris, a close relative of Amphiprion percula. They focused on thyroid hormones, which are known to trigger metamorphosis in frogs.

The clownfish, Amphiprion ocellaris, is one of the rare few species of coral reef fish that can be raised in a lab. Prof. Laudet uses the species to study the hormones involved in life history strategies, including metamorphosis. Credit: OIST

The researchers treated larval clownfish with different doses of thyroid hormones. The higher the dose of thyroid hormones, the faster the clownfish developed the white bars, the team reported. Conversely, when the researchers treated the clownfish with a drug that stopped thyroid hormones from being produced, bar formation was delayed.

The white bars form due to pigment cells, called iridophores, which express a specific subset of genes. Thyroid hormones accelerated white bar formation by activating these iridophore genes, the research team found.

Clownfish larvae treated with thyroid hormones formed a higher number of bands at an earlier stage of development, compared to control larvae that weren’t treated with thyroid hormones. The image shows a control clownfish larvae (top) and a larvae five days after it was given a dose of thyroid hormones (bottom). Credit: Pauline Salis, first author

Next, the scientists tested whether these observations held true the field. When the CRIOBE lab returned to Kimbe Bay, they transported juvenile clownfish from both species of sea anemone back to Dr. Salis in France.

Levels of thyroid hormones were much higher in the clownfish from the giant carpet anemone than in the clownfish from the magnificent sea anemone, Dr. Salis confirmed.

To gain insight into what caused these higher levels of thyroid hormones, the team measured the activity of most genes in the clownfish genome.

“The big surprise was that out of all these genes, only 36 genes differed between the clownfish from the two sea anemone species,” said Prof. Laudet. “And one of these 36 genes, called duox, gave us a real eureka moment.”

Duox, which makes the protein dual oxidase, plays an important role in the formation of thyroid hormones, previous research has shown. The duox gene showed higher levels of activity in clownfish from the giant carpet anemone, compared to clownfish from the magnificent sea anemone.

Further experiments in collaboration with Professor David Parichy from the University of Virginia, U.S., confirmed that duox is important for developing iridophore pigment cells. When the duox gene is inactivated in mutant zebrafish, development of the iridophore pigment cells is delayed, the study found.

Taken together, the data suggests that increased activity of duox in clownfish living in the giant carpet anemone result in higher levels of thyroid hormones, and thus the faster rate of white bar formation as iridophore pigment cells develop quicker.

However, the research raises still more questions for the scientists to answer, including the ecological reason for this variation in the rate of white bar formation.

It may be because the giant carpet anemone is more toxic, with thyroid hormone levels increasing as a response to stress, the researchers speculated.

“Here at OIST, we’re starting to delve into some possible explanations,” said Prof. Laudet. “We suspect that these changes in white bar formation are just the tip of the iceberg, and that many other differences are present that help the clownfish adapt to the two different sea anemone hosts.”

Reference: “Thyroid hormones regulate the formation and environmental plasticity of white bars in clownfishes” by Pauline Salis, Natacha Roux, Delai Huang, Anna Marcionetti, Pierick Mouginot, Mathieu Reynaud, Océane Salles, Nicolas Salamin, Benoit Pujol, David M. Parichy, Serge Planes and Vincent Laudet, 24 May 2021, Proceedings of the National Academy of Sciences.
DOI: 10.1073/pnas.2101634118

Funding: Agence Nationale de la Recherche, National Institute of Science