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Uncategorized

THIRST: NEUROBIOLOGY

Neurobiology of Thirst: Neural Mechanisms that Control Hydration

Scientists at the Tokyo Institute of Technology (Tokyo Tech) provide deeper insights into neural thirst control. Their study published recently in Nature Communications indicates that cholecystokinin-mediated water-intake suppression is controlled by two neuronal ‘thirst-suppressing’ sub-populations in the subfornical organ in the brain; one population is persistently activated by excessive water levels, and the other, transiently after drinking water.

Water sustains life on earth. The first life originated in an ancient sea, and since then, nearly every species that has existed in the past or lives today depends on the exact balance of salt and water (~145 mM; called body-fluid homeostasis or salt homeostasis) for survival. Humans can go weeks without food but will not last more than a few days without water, stressing the importance of this liquid.

The human body has several intricate mechanisms to make sure we consume an appropriate amount of water for maintaining the homeostasis, which is requisite to survival. One of these simple but key “hacks,” is thirst. When the body experiences dehydration on a hot day (noted by the excess of sodium in the body compared to water, a condition called hypernatremia), the brain sends “signals” to the rest of the body, making us crave the tall glass of water. On the other hand, under a condition called hyponatremia, where there is a more water than sodium, we suppress water drinking. The neural mechanisms of how this happens are a subject of great interest.

A team of researchers from Tokyo Institute of Technology, headed by Prof Masaharu Noda, have conducted extensive research into this. In their previous studies, they identified that thirst is driven by the so-called “water neurons” in the subfornical organ (SFO) of the brain, a region just outside the blood-brain barrier. When the body is dehydrated, the plasma levels of a peptide hormone called angiotensin II increase. These levels are detected by special angiotensin II “receptors” of water neurons to stimulate water intake. In turn, under sodium-depleted conditions (where there is more water than sodium), the activity of these water neurons is suppressed by “GABAergic” interneurons. “The latter control appeared to be dependent on the hormone cholecystokinin (CCK) in the SFO. However, the CCK-mediated neural mechanisms underlying the inhibitory control of water intake had not been elucidated so far,” states Prof Noda.

NEUROBIOLOGY OF THIRST
Categories
environment

Fight over Biodegradable Plastics

There’s a spat between tech companies trying to develop a new generation of plastics that biodegrade harmlessly without leaving a trace and skeptics worried that such novel substances won’t live up to their promise and will worsen the plastic waste problem.

The companies are calling for more time to perfect their inventions — which they say differ from earlier efforts to make cleaner plastics — while environmental campaigners demand even firmer regulatory action to get rid of plastic garbage. Firms are also battling against the image problem of an earlier generation of innovative biodegradable plastics that experts say haven’t lived up to the hype.

“The popular understanding of biodegradability is based on legacy solutions such as oxodegradable plastic, many of which unfortunately don’t work,” said Niall Dunne, the CEO of British firm Polymateria, adding that the “landscape has moved on significantly yet outdated perceptions remain.” 

Polymateria has developed a process, called biotransformation, to produce plastic products it says decompose harmlessly when littered.

It involves mixing bio-transformation chemicals with normal plastics to create food and drink packaging, bubble wrap, fruit nets, plastic bags and the like. The technology helped to define a new British standard for biodegradability.

“The role of innovation is consistently underestimated when solving complex global issues, including climate change and plastic pollution,” Dunne said.

But potential innovations like that are facing headwinds.

An expert study, published last week, found that a lack of standards and reliable certification schemes for biodegradable plastics — and, in some cases, misleading labeling — confuses consumers and can “exacerbate” environmental pollution.

The biggest problem, according to the report from the Science Advice for Policy by European Academies, is that while biodegradables can break down under ideal conditions they have a much tougher time doing so in a natural environment like deep in a landfill or on a beach.

Polymateria is tackling those issues. Although it can be recycled in the normal way, its new plastic will decompose into a wax or grease-like substance in a matter of months when exposed to sunlight, air and water. Bacteria and fungi will digest the wax, breaking it down into carbon dioxide, water and more microbes. Most importantly, there are no microplastics left behind.

For now the additives only work when added to the most littered type of plastics — polyolefins, which include polyethylene (plastic bags and packaging) and polypropylene (plastic cups and cutlery, bottle caps and containers).

In lab tests that mimic ambient real-world conditions, “there’s nothing left of polyethylene waxes in 226 days and the polypropylene waxes disappear in 336 days,” said Dunne. 

The plan is to stamp a “recycle by” date on each piece of plastic to show consumers that they have a deadline to dispose of them responsibly in the recycling system before they start breaking down. 

The technology is currently being tested in a handful of countries, including the U.K. and India, but has already helped to define the first standard for measuring biodegradability, published by the U.K.’s national standards body BSI in October.

That European Commission is also busy developing its own policy framework for bio-based plastics and biodegradable or compostable plastics, which it expects to adopt next year.

Not everyone is lyrical about Polymateria.

For one thing, the additive adds roughly 10 to 15 percent to the overall cost of packaging. There’s also the question of whether plastics should be made biodegradable in the first place.

British environmental groups including RECOUP and the Environmental Services Association wrote to the BSI, insisting the standard “will increase the prevalence of litter in all environments.” They fear that the concept of being able to throw away litter and assume it will biodegrade supports the continued use of plastics.

But Dunne said that most of the problem with plastic waste is due to exports to non-EU countries where it’s “not being recycled and is winding up in unmanaged waste systems,” he said, estimating that littering only accounts for 2 percent of the issue.

He argued that the solution is “innovative technologies which permit reuse and recycling” as well as redesigning materials to be biodegradable at the end of their useful life “if we are really serious about actually solving this global problem.”

The European Commission on Tuesday adopted new waste shipment rules going into effect in January that ban the export of plastic waste from the EU to non-OECD countries, except for clean plastic waste sent for recycling.

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Uncategorized

DONATE FOR A CAUSE!!

Hi, I am Tarishi Parmar,
Supporting India For the Cause of Sanitation.

https://www.crowdkash.com/campaign/994/support-tarishi-parmar-s-campaign-to-provide-sanitary-pads-to-underprivileged-to-5000-girls-women-in-15-states-2-ut

Women and girls from low-income backgrounds have been facing a massive menstrual hygiene crisis due to the pandemic. The only source of sanitary napkins for most school-going girls was from government schemes that supply them through government schools, which remain closed amidst the lockdown. Similarly, minimum wage daily labourers women/migrants workers and those from poor homes are unable to afford sanitary napkins as they suddenly have no or very less income. This leads to them using unhygienic methods like paper, rags, etc. This leads to UTIs and other health problems.

Our aim is to provide immediate relief for menstrual health issues faced by women who are from low-income groups, in collaboration with the Live To Inspire, through the distribution of sanitary napkins. They are also educated about the best menstrual hygiene practices.

COVID-19 has impacted millions of people. The worst-hit are the poor, migrants, and daily wage workers. There has been a surge in cases & the situation will only get worse before it gets better. For girls and women from financially weak backgrounds, the issue is compounded by the inaccessibility of menstrual hygiene measures. While we take menstrual hygiene for granted, it is a luxury for them.
The cost of this hygiene kit (including distributing it) is just INR 15 per month per girl. I request all of you to support my campaign so that we can also contribute to their well-being in our own small little way. Let’s come together and do our bit.


About Live to Inspire

It is a consortium of change where youth activists, social organizations, corporates & influencers work under one vision for one development.
The 193 countries of the UN General Assembly adopted the Vision 2030 Development Agenda titled “Transforming our world: the 2030 Agenda for Sustainable Development”, on 25th September 2015. The Sustainable Development Goals (SDGs) are indispensable 17 global goals set by the United Nations in 2015. 

Live to Inspire have taken an initiative to make an independent autonomous Public Interest Foundation named “UNITED FIRST” where they undertake individual responsibility for each cause mentioned under Sustainable Development Goals 2030 by the United Nations. It would be a consortium comprising of Industry Leaders, NGOs, Youth Leaders, and Noble Personalities who will work alongside the Governors of each State in India respectively.
Working on the vision of the 17th SDG of developing partnerships, they are here to create an impact by connecting government, NGO’s and private sectors to achieve common goals addressing both macro as well as micro-level social issues.

EVEN THE SMALLEST DONATION CAN MAKE THE BIGGEST CHANGE!!

Categories
environment

Daring Cities 2020: Top 5 most popular thematic sessions

A first-of-its kind virtual event, Daring Cities 2020 positioned itself as the global forum for urban leaders taking action on the climate emergency. With 100 sessions and more than 200 hours of online discussions designed with urban leaders in mind, the event unfolded over the span of three weeks.

The four plenary days at the heart of Daring Cities included a special addresses from the United Nations Secretary-General, António Guterres, in the Daring Cities opening, a special three part session in collaboration with TED, the launch of the Redesign2020 Platform, the launch of the UNDRR Making Cities Resilient 2030 campaign and a look forward to the future with remarks by high level speakers

In addition to these core plenary sessions, Daring Cities’ sessions covered topics from nature-based solutions and innovative climate finance, to urban resilience and social equity. Hundreds of city leaders, practitioners, researchers, and experts shared their insights and experiences on how to take radical action in our cities, towns and regions to tackle the climate emergency, especially in light of the current Covid-19 pandemic.

Of those rich thematic offerings, here are the five most popular sessions of Daring Cities 2020. All session recordings are available on the website and are free for anyone with a Daring Cities 2020 profile.  

Renewable Energy in Cities: Opportunities for Green Growth through Recovery Packages

Energy systems are the backbone of urban activities and systems from public transport to heating and cooling. Effective local renewable energy deployment can give cities the opportunity to achieve a wide range of socio-economic and environmental objectives. 

In this session, attendees had a closer look at energy supply and efficient energy consumption. They learned about the opportunities that renewable energy presents for cities to achieve a wide range of objectives, including fighting air pollution, improving public health, and mitigating climate change. 

Sustainable Urban Renewal through Nature-Based Solutions: Lessons Learned from Chinese and German Cities

Rapid and irreversible urbanization has escalated the impact of environmental degradation, climate change and various hazards and crises. But these challenges have given rise to a growing trend of sustainable urban renewal. 

Governments of different countries, including China and Germany, are endeavoring to support the transformation and regeneration of their cities and communities to become more sustainable, resilient and livable.

Co-organized by the Sino-German Urbanisation Partnership (SGUP), which aims to promote the exchange of experiences and expertise in the field of sustainable and integrated urban development between China and Germany, this virtual exchange workshop brought together key stakeholders to share knowledge and practices on sustainable urban regeneration through applying nature-based solutions.

Introducing CitiesWithNature to Daring Cities for Climate Resilience

Nature provides immense value and multiple benefits to urban communities. The loss of nature is a global crisis in its own right, and cities are not only part of the problem, but are also key to the solution. 

This session introduced CitiesWithNature, a global partnership initiative co-founded by ICLEI, the International Union for the Conservation of Nature, and The Nature Conservancy to the Daring Cities audience. The initiative provides a shared online platform for cities and regions to connect, learn, share, and inspire each other in pursuit of achieving global impact through collective local action for nature.

Attendees of this session left with a better understanding of how their city can become a city that is daring enough to demonstrate their commitment to nature. 

Innovative Climate Finance Case Studies

Local governments are at the frontline of climate action. Yet subnational governments often struggle to access finance required for sustainable, low-to-no emission, climate resilient development.

The session provided a platform for local governments to interact with financial experts, helping each other to better understand how to find and use innovative financing tools such as green bonds, revolving funds, energy performance contracts or crowdfunding for their climate project.

Nature-Based Solutions For Cities – What Are They And How Can Their Uptake Be Increased?

Many cities are looking for solutions to protect themselves from the impacts of disasters and climate change. However, many of these solutions are expensive, and they are not always sustainable or built for the growing impacts of natural hazards. Despite growing scientific evidence on their potential, the adoption of these nature-based solutions is still not widespread, especially in cities. 

This session not only explored barriers but also promising ways forward, including best practices from frontrunner cities in different ecosystems, research findings and capacity building activities. It took a deep dive into how the perception and use of urban green areas changed in the context of COVID-19 and what opportunities this change might present for the acceleration of nature-based solution uptake.

By bringing together panelists and participants from research, policy and practice, they were able to get a better understanding of how cities can best be supported in adopting nature-based solutions. 

Categories
Biology

WOO-HOO!! WE CAN NOW REVERSE CELL AGING!

Turning off a newly identified enzyme could reverse a natural aging process in cells.

Research findings by a KAIST team provide insight into the complex mechanism of cellular senescence and present a potential therapeutic strategy for reducing age-related diseases associated with the accumulation of senescent cells.

Simulations that model molecular interactions have identified an enzyme that could be targeted to reverse a natural aging process called cellular senescence. The findings were validated with laboratory experiments on skin cells and skin equivalent tissues, and published in the Proceedings of the National Academy of Sciences (PNAS). 

“Our research opens the door for a new generation that perceives aging as a reversible biological phenomenon,” says Professor Kwang-Hyun Cho of the Department of Bio and Brain engineering at the Korea Advanced Institute of Science and Technology (KAIST), who led the research with colleagues from KAIST and Amorepacific Corporation in Korea. 

Cells respond to a variety of factors, such as oxidative stress, DNA damage, and shortening of the telomeres capping the ends of chromosomes, by entering a stable and persistent exit from the cell cycle. This process, called cellular senescence, is important, as it prevents damaged cells from proliferating and turning into cancer cells. But it is also a natural process that contributes to aging and age-related diseases. Recent research has shown that cellular senescence can be reversed. But the laboratory approaches used thus far also impair tissue regeneration or have the potential to trigger malignant transformations. 

Professor Cho and his colleagues used an innovative strategy to identify molecules that could be targeted for reversing cellular senescence. The team pooled together information from the literature and databases about the molecular processes involved in cellular senescence. To this, they added results from their own research on the molecular processes involved in the proliferation, quiescence (a non-dividing cell that can re-enter the cell cycle) and senescence of skin fibroblasts, a cell type well known for repairing wounds. Using algorithms, they developed a model that simulates the interactions between these molecules. Their analyses allowed them to predict which molecules could be targeted to reverse cell senescence.

They then investigated one of the molecules, an enzyme called PDK1, in incubated senescent skin fibroblasts and three-dimensional skin equivalent tissue models. They found that blocking PDK1 led to the inhibition of two downstream signaling molecules, which in turn restored the cells’ ability to enter back into the cell cycle. Notably, the cells retained their capacity to regenerate wounded skin without proliferating in a way that could lead to malignant transformation.

The scientists recommend investigations are next done in organs and organisms to determine the full effect of PDK1 inhibition. Since the gene that codes for PDK1 is overexpressed in some cancers, the scientists expect that inhibiting it will have both anti-aging and anti-cancer effects.

THE SCIENTISTS CONDUCTED WHAT IS KNOWN AS AN ENSEMBLE MODEL SIMULATION TO IDENTIFY MOLECULES THAT COULD BE TARGETED TO REVERSE CELL SENESCENCE. THEY THEN USED THE MODEL TO PREDICT THE EFFECTS OF INHIBITING PDK1 IN SENESCENT CELLS, AND CONFIRMED THE RESULTS IN LAB-CULTURED CELLS AND SKIN EQUIVALENT TISSUE MODELS.
Categories
Covid-19 environment

Let’s go BLUE for a COVID-19 recovery!!

“The ocean economy may be a victim of the impacts of the COVID-19 crisis, but it also holds solutions for rebuilding a more resilient, sustainable and equitable post-COVID world.”

– A Sustainable & Equitable Blue Recovery to the COVID-19 Crisis Report

Ocean and coastal habitats provide an essential workplace for the world’s small-scale fishers, and coastal communities rely on the ocean for jobs, food, health, and cultural traditions. In fact, the ocean economy adds approximately US$1.5 trillion in value globally (OECD 2016). But the COVID-19 pandemic disproportionally impacts the ocean economy and these communities, especially those from Small Island Developing States (SIDS).

new special report commissioned by the High-Level Panel for a Sustainable Ocean Economy (the Ocean Panel) recognizes the ocean economy’s vital role and the pandemic’s devastating impacts on ocean workers and the marine sector—and importantly, offers recovery solutions.

“A Sustainable and Equitable Blue Recovery to the COVID-19 Crisis”, as the name implies, recognizes the power of nature to help solve daunting global issues like climate change and pandemics. The report was released ahead of Climate Week NYC and a Rare-facilitated high-level roundtable meeting of coastal countries, where officials issued a joint message acknowledging the importance of the small-scale fishing sector to a blue (or green) recovery: that by implementing coastal and marine nature-based solutions, small-scale fishers can improve food security, nutrition, and the local economies of coastal nations, and enhance coastal resilience from climate change.

As a member of the Ocean Panel’s Advisory Network, Rare supports the five blue stimulus opportunities for government investment in COVID-19 crisis recovery outlined in the report. These proposed solutions deliver short-term relief to the economy and long-term economic, social, and environmental resilience. Moreover, they are considered a win-win for immediate assistance and forward-looking sustainable planning, known as a ‘no regrets’ investment strategy.

Fish Forever, Rare’s coastal fisheries program, prioritizes the report’s solution related to coastal and marine ecosystems: Invest in Coastal and Marine Ecosystem Restoration and Protection. Fish Forever uses behavioral insights to inspire fishing communities — fishers, fish buyers and traders, community members, and their local government — to adopt more responsible behaviors related to coastal fishing and implement nature-based solutions to protect their natural resources.

Investing in a nature-based solution like restoring and protecting coastal and marine ecosystems benefits coastal fishing households and their communities. This solution also has a host of benefits critical for a blue recovery, including the following five:

  1. Improves Food Security – Protecting coastal ecosystems supports ample fish resources and fish breeding habitat, which safeguards fishing communities by strengthening food security during times of crisis. Technology innovations, like Rare’s OurFish App referenced in the report, show how a nature-based approach to resource management benefits the community and improves food security: the app digitally helps to manage and understand fish stock and finance trends and enables fishing communities to monitor the value, type and local amount of fish caught.
  2. Enables Sound Financial and Household Decision-Making – Establishing Savings Clubs led by small-scale fishers empowers its members, often majority women, to manage their long-term household finances. It also raises awareness of the actions needed to enforce fish sanctuaries for coastal habitat protection and community livelihoods’ sustainability. This approach to behavior change “can powerfully affect the long-term strategy behind coastal fisheries conservation and the goal of ending overfishing,” as the report explains.
  3. Enhances Economic, Social, and Environmental Resilience – Investing in coastal and marine ecosystem restoration and protection can also expand job opportunities, such as protected areas enforcement officers, development planners, environmental engineers, and ecological restoration scientists. In addition to job security, nature-based solutions support the healthy natural resources that protect small-scale fishers’ livelihoods.
  4. Manages Natural Resources Sustainably – Ensuring coastal and marine ecosystem integrity further increases economic productivity by improving fisheries and tourism opportunities. Sustainable management also allows for more significant investment opportunities in blue carbon activities focused on climate mitigation and adaptation benefits from mangroves, seagrasses, and tidal salt marshes.
  5. Builds Community Pride – Stakeholder engagement and collaboration with public and private sectors, including small-scale fishers and their families, are critical for building pride in and ownership of more sustainable behaviors and community-based programs. Co-owning and managing natural resources and ensuring the inclusion of women and Indigenous communities has also demonstrated long-lasting benefits and delivers on many of the UN’s sustainable development goals.

Farmers and fishers rely on healthy ecosystems and strong local governance and management to thrive. Building back better from the impacts of COVID-19 will require a global blue recovery effort that not only prioritizes nature-based solutions but empowers coastal communities and their leaders to champion blue solutions.

BLUE solutions for COVID-19 recovery

Categories
Biology Evolution human body

New microevolutinary change :Median artery in the human forearm

The median artery is the main vessel that supplies blood to the forearm and hand, when first formed in the mother’s womb, but it disappears once two arteries seen in adults develop.

The radial and ulnar arteries usually replace the median artery during developmental stages in the womb, so most adults obviously don’t have a median artery, but increasing numbers of cases retain it, so a person can have all three arteries.

The median artery is now present in about 35% of people and researchers predict that people born 80 years from now will all carry a median artery if the trend continues.

“The median artery offers benefits because it increases overall blood supply and can be used as a replacement in surgical procedures in other parts of the human body,” said senior author Professor Maciej Henneberg, a researcher in the Biological Anthropology and Comparative Anatomy Research Unit at the University of Adelaide and the Institute of Evolutionary Medicine at the University of Zurich.

“This is microevolution in modern humans and the median artery is a perfect example of how we’re still evolving because people born more recently have a higher prevalence of this artery when compared to humans from previous generations.”

In the study, Professor Henneberg and colleagues aimed to investigate the prevalence of persistent median arteries in postnatal humans over the last 250 years and to test the hypothesis that a secular trend of increase in its prevalence has occurred.

They found a total of 26 median arteries in 78 upper limbs (a prevalence rate of 33.3%) obtained from Australians aged 51 to 101 years.

“Our study into the prevalence of the artery over generations shows that modern humans are evolving at a faster rate than at any point in the past 250 years,” said lead author Dr. Teghan Lucas, a researcher in the Department of Archaeology at Flinders University and the School of Medical Sciences at the University of New South Wales.

“Since the 18th century, anatomists have been studying the prevalence of this artery in adults and our study shows it’s clearly increasing.”

“The prevalence was around 10% in people born in the mid-1880s compared to 30% in those born in the late 20th century, so that’s a significant increase in a fairly short period of time, when it comes to evolution.”

“This increase could have resulted from mutations of genes involved in median artery development or health problems in mothers during pregnancy, or both actually,” he added.

“If this trend continues, a majority of people will have median artery of the forearm by 2100.”

“When the median artery prevalence reaches 50% or more, it should not be considered as a variant, but as a normal human structure,” the authors said.

Lucas.et al. find that the prevalence of the persistent median artery in postnatal life approximately tripled over the last 125 years.

Categories
environment

“Cocktail “: The plastic eating enzyme

The scientists behind re-engineering of the plastic-guzzling enzyme PETase have now gone a step further. These scientists have created an enzyme medley, which is up to six times faster to digest plastic.

Another enzyme, found in the same rubbish dwelling bacterium like PETase, has been combined with the latter to speed up the disintegration of plastic. PETase disintegrates polyethylene terephthalate into its building blocks. This creates an opportunity to reprocess plastic infinitely and reduce greenhouse gases and plastic pollution driving climate change.

Meanwhile, PET is the commonly used thermoplastic to make clothing, carpets, and single-use drink bottles. It takes hundreds of years for PET to disintegrate in the environment, but PETase can reduce this process to days.

Discovery of Plastic-eating PETase first step in Plastic Recycling revolution

With the discovery of PETase, it set up the prospect of a revolution in plastic recycling, thereby creating a potential low-energy solution to deal with plastic waste. To establish this, the natural PETase enzyme engineered in the laboratory featured to be almost 20 percent faster at disintegrating PET.

Going further, the same team of scientists have combined PETase and a second enzyme MHETase, for much bigger improvements. The mixing of PETase and MHETase doubled the speed of breakdown of PET, and designing a connection between the two enzymes created a super-enzyme, which further increased the speed of the activity by three times.

The study published in the journal Proceedings of the National Academy of Sciences was co-led by scientists who engineered PETase.

“In the natural phenomenon, PETase attacks the surface of the plastic and MHETase chops it further. Likewise, for it seemed natural if the two enzymes could be used together, to mimic the natural phenomenon,” opine the associates of the study

Categories
Biology Covid-19 human body

Covid 19’s lingering problem : Heart damage

Massachusetts General Hospital pathologist James Stone can tell that most of the hearts he’s examined from COVID-19 patients are damaged from the first moment he holds them. They’re enlarged. They’re heavy. They’re uneven.

What he can’t tell—at least until he starts looking at samples of the tissue under a microscope—is exactly how those hearts were damaged, and whether it is a direct result of SARS-CoV-2 infection.

Early in the pandemic, other clinicians noted that even some patients who didn’t have preexisting heart conditions experienced cardiovascular damage while fighting COVID-19 infections, pointing to a possible causative link. Researchers had found, for example, that 8–12 percent of hospitalized COVID-19 patients had elevated levels of muscle contraction–regulating proteins called troponins—a sign of heart damage—and that these patients had an increased risk of mortality compared with those who didn’t have excess troponins. And early observations of patients in China who suffered reduced ejection fraction—the amount of blood getting pumped out of the heart each time it contracts—led researchers to suggest that these individuals were likely experiencing myocarditis, a severe form of inflammation that can weaken the heart and is commonly associated with infections.

But Stone and his collaborators’ analysis of heart tissue from 21 patients who died of COVID-19, published today (September 24) in the European Heart Journal, shows that while 86 percent of the patients did have inflammation in their hearts, only three had myocarditis. Several had other forms of heart injury, such as right ventricular strain injuries.

“The problem we identified in this study is that there’s other types of myocardial injury in these patients that is also causing elevated troponins,” says Stone. His international team sought to determine the mechanisms through which the disease damaged the heart and found that some conditions “really haven’t been talked about at all in the [COVID-19] papers that have previously been published.”

The pathologists observed a median of 20 slides from each heart, which is more than are included in most other studies regarding COVID-19’s cardiac effects. George Abela, a cardiologist at Michigan State University who was not involved in the study, tells The Scientist in an email, “This provides a more in-depth view of the extent of injury.”

The researchers expected to find some macrophages, a type of white blood cell that indicates inflammation, as pathologists had observed macrophages in the hearts of SARS patients during the 2003 outbreak. But Stone says he was surprised to see just how common these were—18 out of 21 COVID-19 patients’ hearts harbored macrophages that exhibited this type of inflammation. “It was really quite extensive,” he says.

As they analyzed the hearts further, the pathologists noted that only three patients had myocarditis, while four showed signs of heart injury due to right ventricular strain and another four had small blood clots in the vessels in the heart. It’s not clear why patients experience such inconsistent cardiac issues.

Abela says these findings have implications for treatment. For example, if the patient has right heart failure, a condition where the right side of a patient’s heart is not pumping enough blood to the lungs, a device that mechanically helps the heart pump blood might help, rather than drugs that target the inflammation or infection, which could be used to treat myocarditis.

Because so many of the hearts were infiltrated by macrophages, the researchers say that it may be difficult to discern who is experiencing myocarditis, which is characterized by different inflammatory cells—lymphocytes—while patients are alive. The two cell types would appear similar on tests that image the hearts of living patients. So, the team looked back at the patients’ medical records to see if they could find patterns in clinical tests that would reveal the type of heart damage when it still might be treatable. The three patients with myocarditis all had both troponin levels above 60 ng/mL and abnormal ECG readings while in the hospital. Only 15 percent of the patients without myocarditis had this combination.

The findings need to be replicated in larger groups of patients but could help doctors determine the best course of treatment for heart damage due to COVID-19, Stone says. The study is “giving the cardiologists and the ICU doctors that are taking care of these patients a roadmap of the changes that are going on in the heart.”

“Novel disease entities like SARS-CoV-2 reinforce the tremendous importance of continuing our efforts at continuing to facilitate autopsy evaluations,” says Allan Jaffe, a cardiologist at the Mayo Clinic, in an email. “This consortium of hospitals have added substantially to our knowledge of Covid disease.”

Categories
Biology

“THE KILLER MUTATIONS”

Scientists have discovered a handful of ultrarare mutations present in our cells from birth that likely shave years off a person’s life. Each of these DNA variants, most likely inherited from our parents, can reduce life span by as much as 6 months, the researchers estimate. And different combinations can dictate how long people live before developing age-related diseases such as cancer, diabetes, and dementia.

A person’s genes don’t set a specific natural life span—diet and many other factors play large roles, too—but studies have shown that DNA variants can influence the aging process. Biologists chalk up less than one-third of that influence to the genes we inherit. The source of other age-influencing DNA variation is environmental: Sun damage, chemical exposure, and other insults that create thousands of random mutations. Each cell’s collection of these environmental mutations differs, and most don’t greatly impact a person’s life span.

Hunting for these rare mutations, which are found in less than one in every 10,000 people, required a group effort. Harvard University geneticist Vadim Gladyshev, a senior co-author in the new study, partnered with academic colleagues and a biotech company called Gero LLC to scour the UK Biobank, a public database containing the genotypes of about 500,000 volunteers.

Using more than 40,000 of these genotypes, the team looked for correlations between small changes in DNA and health conditions, a so-called genomewide association study. Specifically, the variants they were targeting knock out genes entirely, depriving all the cells in the body of certain proteins.

On average, each person is born with six ultrarare variants that can decrease life span and “health span,” the amount of time people live before developing serious diseases, the team reports this month in eLife. The more mutations, the more likely a person was to develop an age-related illness at a younger age or die. “The exact combination matters,” Gladyshev says, but in general, each mutation decreases life span by 6 months and health span by 2 months.

The results build on what is already known about aging: “Family genes” matter. But rather than studying the common mutations found in especially long-lived people, researchers can now target rarer variants present in everyone. Gladyshev hopes this information can be used in clinical trials to categorize participants by their mutations in addition to things like gender and actual age.

He admits the findings are potentially controversial, as they minimize the perceived contribution to

aging of environmental “somatic” mutations acquired throughout life. Somatic mutations “live in a larger universe of age-related changes” influenced by lifestyle, he says, adding that changes to hormone and gene expression also come with age. “They [all] contribute to the aging process, but on their own they do not cause it.”

Jan Vijg, a geneticist at the Albert Einstein College of Medicine who studies the role of somatic mutations in aging, agrees, though he adds that somatic mutations can still cause diseases such as skin cancer that decrease life span.

Alexis Battle, a biomedical engineer at the Johns Hopkins University School of Medicine, points to an important caveat, however: The new research only looked at the “exome,” the 1% of the genome that actively builds the proteins that direct our cells. The rest is largely a black box, although growing evidence shows it can affect gene expression. Both Battle and Vijg agree that this DNA could be even more important in aging than the regions targeted by Gladyshev and his colleagues.

Going forward, Gladyshev would like to repeat his analysis on DNA from centenarians: those that live to be older than 100. “Most of the previous research focused on what these people have that makes them long-lived,” he says. “But [we want to look at] the opposite—it’s what they don’t have.”

Illustration of a damaged ribonucleic acid or dna strand