Is GDF11 the key protein in young blood that rejuvenates older animals?

Research over the past few years have pointed toward a protein known as GDF11 as the key protein that is responsible for rejuvenating older mice when they are transfused with younger mice blood. However, research studies by the pharmaceutical company, Novartis challenge this idea and suggest GDF11 may not play such an important role in this effect as previously thought. 

As stated in an editorial by Jocelyn Kaiser at Science magazine:

"The Novartis group does not question that young blood renews old mice. But they say the Harvard group’s explanation is wrong. Their paper, published today in Cell Metabolism, casts doubt on the assays used in the earlier research and suggests that GDF11 actually inhibits muscle regeneration. “The whole premise is incorrect,” says stem cell researcher Michael Rudnicki of the Ottawa Hospital Research Institute, who co-wrote a commentary accompanying the paper. Others are more cautious, but agree that the new work undermines part of the original GDF11 claim. “GDF11 does not go down with age,” says Thomas Rando, a biologist at Stanford University in Palo Alto, California.

Harvard stem cell biologist Amy Wagers, who led much of the original work, says the Novartis data on GDF11 levels are not persuasive. And although they “appear to conflict with” her group’s, “we are actually very excited to see the Novartis data,” she says. “We remain convinced that at least one form of GDF11 declines in blood with age and that maintaining GDF11 levels in an appropriate physiological range is essential for muscle health.”


So the jury may still be out on this particular issue, but one thing remains clear--transferring blood from young mice has a rejuvenating effect on older mice. As such, something must be mediating such effects. I am sure the details will eventually be ironed out with so much effort being put into this research topic by academia and pharmaceutical companies. I am eager to see how this all plays out.


Jocelyn Kaiser. Doubts cast on 'rejuvenating' protein. Science. 19 May 2015 
http://news.sciencemag.org/biology/2015/05/doubts-cast-rejuvenating-protein

#science   #research   #rejuvenation   #aging  #anti-aging 
#biology   #GDF11   #harvard  #novartis  

Top 5 Reasons I Like Being a Scientist

I have often been asked, and perhaps asked myself even more often, why did I become a scientist? What drove me to get a Ph.D. in biomedical research? What keeps me motivated to continue pushing onward when experiments and other aspects of the work seem to actively be working against me? Despite the difficulties I face in research, and my arena is academic research for those who do not know, there is really no other job I would rather do...plain and simple. But to really break this down into key reasons why I love what I do, I put together this Top 5 list (and because lists are awesome). I hope this is helpful for those who are thinking about pursuing a similar path, and is enjoyable for those interested or who just like to read lists.



Reason #1: My particular area of research, neurological injury and disease, needs advancements in the understanding of pathology and in therapeutic development and experimentation and my work could one day improve people's lives.
There are still so many things to learn about how injury and disease progresses in the nervous system, and understanding these aspects is critical to developing appropriate and effective treatments. People live with neural injuries and degeneration every day, and even small steps forward are big steps for those holding out hope.


Reason #2: Being a scientist keeps my brain active and helps quench my never-ending thirst for knowledge.
Working as a researcher means I have to stay very current with the relevant scientific publications and advancements in my field, and even related fields. This pushes me to identify what are the next critical questions to be answered or how a certain type of research could be expanded. Designing experiments to address these problems and considerations is a highly creative and pivotal step in the research process. Mastering the art of interpreting what others have done, and what you need to do next is one of the most important parts of my job, and this must occur regularly and often long before any experiments actually get started.


Reason #3: Writing and publishing my research is incredibly exciting and rewarding to me.
Working as an academic researcher, publishing your work is essential for advancement in your career, and to effectively contribute new knowledge that pushes your field of study forward. I love to write, and I greatly enjoy telling the story of my research and interpreting what my findings mean in the context of the study and field of research in general. This requires practice, diligence, acceptance of criticism from you peers, and rejection as your papers often get rejected from several publications before being accepted. If I did not love to write, this process could be an extremely difficult part of my job, and I know many good researchers who have left science or went into industry or another sector to avoid having to write and publish as a key part of their career. 


Reason #4: When I design and perform experiments and obtain results, I am often the first person to have discovered that set of information on that given topic.
This truly a great part of science. When you do work to push your field of study further, you develop an area of expertise, and ask questions that have either never been asked or attempted to be answered in the same way you plan to do so. As such, you end up collecting data and results that reveal information that has never been revealed before. Even if some results you obtain replicate a previous study's findings, your interpretation may be entirely different based on the context of your particular study. It is kind of like digging in a big field, and you have a tiny plot of land that's yours and yours alone. The deeper you dig, the more and more things you dig up that no one else has ever excavated.
I am always fascinated by obtaining data, as you never really know what you will find; even if you have some predictions, those may be wrong and you end up with something totally unexpected. I often say that I end up with even more questions when I do experiments than answers to the questions I originally had.


Reason #5: I get to go to conferences and meet others with like (or different) interests and share ideas.
In my opinion, science is an extremely social occupation. People sometimes have the misconception that scientists and researchers are non-social geeks who spend all day in the lab. Though it is often true we spend long hours in the lab working, I find that I have had the opportunity to give dozens of talks on my work, present at local, regional, national, and international conferences, and meet other researchers at these events who have amazing ideas and love to discuss them with others that are interested. I can think of few other, if any, careers that would have afforded me such unique opportunities for networking and collaboration. I greatly look forward to attending conferences and symposia and giving and listening to scientific talks. It is an important part of what I do, I take it seriously, and I enjoy it immensely.



This was my short list of reasons why I became and enjoy working as a scientist. However, there are many other things I enjoy about what I do. The process of becoming a researcher has been transformative and has changed my perspective of myself and how I think about the world around me. It is not perfect, but no job truly is. I hope this little slice of my life is educational and informational, and I am always happy to take emails from anyone who has questions on what it's like going to graduate school, being in research, or that wants to further discuss my research.

#top5   #science   #research   #researchers   #academia  #biomedical   #medicine   #neuroscience  

Smart phone-microscope and app aids researchers in diagnosing parasites in the field

"Low-tech" would be the term for the level of equipment doctors and health care workers often prefer or have available in working in remote or highly-underserved areas. In many ways, this classic medical equipment serves them well, and allows them to provide care when otherwise the residents in these regions may receive little if any at all. However, in some instances, low-tech equipment cannot help doctors identify certain pathogens which may affect their ability to rapidly diagnose and provide the correct treatment. Enter, the smart phone enabled microscope. With this handy bit of high-tech, doctors and the health care team can now go where it has been generally not possible to go concerning diagnosis of certain disease and investigation of certain tissue and organs in the human body.

Daniel Fletcher of the University of California, Berkeley, and his colleagues report in a recent article in Science Translational Medicine a camera-phone microscope and app that permits rapid identification of the African eye worm parasite Loa loa in blood samples. Loa loa develops into a worm that wiggles into eye tissue, and becomes an even bigger proble if is acquired with two other parasitic nematodes, Onchocerca volvulus (causes river blindness) and Wuchereria bancrofti (causes severe limb swelling). This compounded problem results from the existence of one drug, called ivermectin, used treat the two other parasites can cause induce unintended brain swelling if a person also has L. loa infection.


How does the smart phone/microscope help in this regard? Well, camera-based microscopes have been used for several years in the field, but a major limitation was that once you prepared a specimen, by blood collection and smearing blood on a slide, all the phone-based scope could do was magnify and provided no real way to improve up what a typical microscope could do. This new device, developed by Fletcher and associates allows someone to insert blood in a capillary tube into 3D-printed plastic case with a magnifying lens. The plastic case then can be placed around an iPhone, putting the lens and sample directly over the camera.


The app that corresponds to this device "records video of the magnified blood sample and uses an algorithm to look for movements in the fluid that match up with characteristics of L. loa. Based on this, the app accurately counts how many parasites are present. It has to be used around midday, during the brief period when L. loa typically are active but the other two nematodes are not."


The potential for modifying this device and application for use in detecting other parasites is clearly there. Other researchers are already hot on the trail in developing phone software to detect soil-based parasites like hookworm and whipworm. So, as smart phones become more pervasive in society and, and we find them in use in the far reaches of the world, we can be sure someone is thinking about not just how to get the best signal or download rates. There are scientists and doctors out there really putting these devices into practice in helping treating those that likely would go untreated. Technology and medicine is a great combination.

#science   #medicine   #biomedicaltechnology   #smartphone  #microscope   #diagnosis   #parasites   #bloodborne   #Africa   #app  #research  

Happy Mother's Day! It turns out you share more than just genes with Mom

As we all thank our Mothers today for the love and sacrifices (not the least of which was carrying you inside her for the better part of a year) made throughout the years on our behalf, research suggests we share a bit more that genes and memories with our mothers. During pregnancy, a process called fetal-mother microchimerism facilitates an exchange of cells between mother and baby and at birth both have a little piece of the other as a little memento, if you will, of the nine month journey.


Research has shown that cells from developing fetuses can be found throughout a mother's brain, bones, in circulating blood and within her heart. In fact, if the heart is damaged, fetal cells that migrate toward the heart may be involved in some repair processes. According to Laura Sanders from Science News, this fetal contribution of cells to the mother maybe a form of payback for all the baby takes from the mother during gestation.


"Growing fetuses slurp nutrients and energy out of a mother’s body during pregnancy (not to mention the morning sickness, heartburn and body aches). In return, fetuses offer up these young, potentially helpful cells. Perhaps these fetal cells, which may possess the ability to turn into lots of different kinds of cells, can help repair a damaged heart, liver or thyroid, as some studies have hinted."


However, this is not a one-way cel sharing process, as the mother will also have cells migrate into the fetus which means cells contributed by older siblings to your mom during their gestation could end up in you along with those specifically from your mother during yours. Some evidence suggests microchimerism may influence detrimental processes such as miscarriages, but much more research is needed to better understand this process overall.


So, this Mother's Day, remember there really is a part of you in her and her in you, in addition the the genetics that bind us as family. Just another reason to appreciate all she has done for you, and how you have been important in her life.


Gammill and Nelson (2010) Naturally acquired microchimerism. Int J Dev Biol. 2010; 54(2-3): 531–543.://www.ncbi.nlm.nih.gov/pmc/articles/PMC2887685/

#mothersday   #mothersday2015   #happymothersday   #cells  #biology   #research   #science   #sciencenews   #pregnancy  #baby   #mother  

Silver-tainted "zombie" bacteria kill other bacteria

Silver has long been known to possess potent anti-bacterial properties. Silver damages bacterial membranes, penetrate the cells, bind DNA and inhibit essential functions for bacterial survival. This proves deadly to bacteria. New research suggests that silver-treated bacteria retain silver particles in their bodies after death, and the dead bacteria remain as a toxic vehicle for other surrounding bacteria. According to Emily Conover at AAAS, the researchers:

"First killed a sample of the bacterium Pseudomonas aeruginosausing a solution of silver nitrate. Then, they carefully separated the dead bacteria from the silver solution. When they exposed living bacteria to the dead, they witnessed a microscopic massacre-Up to 99.99% of the living bacteria met their doom."

Microscope images of P. aeruginosa before (a and d) and after (b, c and e) silver treatment; the black (b) and white (e) granules are silver deposits that trigger the "zombies" biocidal activity. Copyright 2015, Wakshlak et al. doi:10.1038/srep09555.

What is interesting about this finding is that silver solutions have long been used for its anti-septic and anti-germicidal properties. This new research suggests that bacteria exposed to silver take it up, die, and act like bacterial "zombies" when exposed to other healthy bacteria. So, rather than creating devices or engineered materials to release silver over a time-course for sustained silver release and thus, anti-bacterial efficacy of a silver treatment, recirculating silver-"infected" bacteria could also generate an extended temporal ability to promote bacterial death. Mostly, I think it is interesting that a simple experiment changed the perspective and potential use of a long utilized chemical for medically-related purposes. There are still basic experiments and simple ideas out there can that can make an impact if you know where to look and have an idea what you are looking for.

Racheli Ben-Knaz Wakshlak, 

Rami Pedahzur

& David Avnir

 (2015) Antibacterial activity of silver-killed bacteria: the "zombies" effect. 

Scientific Reports

 

5,

 

Article number:

 

9555

 

doi:10.1038/srep09555.

http://www.nature.com/srep/2015/150330/srep09555/full/srep09555.html

#science   #bacteria   #antibacterial   #medicine   #research  

The truth behind bars: Representations and misrepresentations of data sets in research articles

Figure 1. Multiple data sets can be presented as the same bar graph.
(Weissgerber et al. 2015).

One of the most common graphical representations of data in research papers is the bar graph. If you read my recent post, you saw that I represented percentages of respondents in different groups in a survey in such a graph. However, it is not the most accurate way to display all types of data collected and analyzed in experimental studies. For a simple number, like a percentage, a bar graph is sufficient; however, when you have multiple data points from individuals within a group, representing continuous data, showing the height or length of a bar as the average, plus and minus an error bar that represents a measure of the variation, is likely hiding the true nature of the data. What I mean by this is that bar graphs hide the spread of the data points, which can result in altogether different interpretations of the data. It is generally recommended that authors use scatter plots to show every data point, especially in studies with small sample sizes. Various sets can be represented by the exact same bar graph (see Figure 1 from the linked paper) The open-access article published last week in PLOS Biology by Weissgerber et al. gives several informational examples as to why this is the case.

In this study, the authors performed a systematic review of approximately 700 research articles published in top tier physiology journals and assessed the use of different types of graphs to represent various kinds of data. The authors state in the abstract:


"Papers rarely included scatterplots, box plots, and histograms that allow readers to critically evaluate continuous data. Most papers presented continuous data in bar and line graphs. This is problematic, as many different data distributions can lead to the same bar or line graph. The full data may suggest different conclusions from the summary statistics."


This should be taken as a nudge for scientists to think about displaying their data with more appropriate graphical representations. Most scientists are culpable for using bar graphs in this sense. Perhaps not only will this improve the interpretation and discussion of the data by the researchers, but also the readers as it improves the transparency of the collected data by pulling the curtain off and exposing it as it should.


Weissgerber TL, Milic NM, Winham SJ, Garovic VD (2015) Beyond Bar and Line Graphs: Time for a New Data Presentation Paradigm. PLoS Biol 13(4): e1002128. doi:10.1371/journal.pbio.1002128.http://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.1002128

Conservative Republicans stand alone in views toward climate change

A recent Gallup survey revealed that most conservative Republicans believe that climate change will not occur or will not take place during their lifetime. According to Jake Miller from CBS News:

"Forty percent of self-identified conservative Republicans believe global warming will never happen, according to the data, while 17 percent believe it will affect future generations. Only 37 percent of GOP conservatives believe the current generation will have to deal with the effects of a changing climate."

All other ideological groups surveyed responded quite differently than the Conservative Republicans concerning climate change occurrence during their lifetime.

• Liberal Democrats: 89%
• Moderate Democrats: 78%
• Independents: 66%
• Moderate Republicans: 64%
• Conservative Republicans: 37%

I find these responses quite interesting. As you move from one end of the political spectrum, you see a decreasing trend that really drops off when you reach the Conservative Republican category. The accompanying graph I created from the above numbers visually drives home this point. Climate change is and will be a hot topic of discussion among politicians and non-politicians alike. If a majority of most political groups feel climate change is something that is or will be an issue for the current generation, and Conservative Republicans feel the opposite, I will be watching with great interest to see how this issue is handled in upcoming elections. A link to the recently released Gallup survey results is provided below.This webpage also provide some other insightful tidbits of data you can read more about.

Andrew Dugan.
Conservative Republicans Alone on Global Warming's Timing. 4/22/2015.
http://www.gallup.com/poll/182807/conservative-republicans-alone-global-warming-timing.aspx?utm_source=Politics&utm_medium=newsfeed&utm_campaign=tiles

Peer reviewers do actually identify valuable research for funding

It is the best of times, it is the worst of times...today's researcher might say. Technology allows for advanced experiments to rapidly provide large datasets to answer questions that were unanswerable a generation ago. The downside is, that research like this is expensive, there are many more researchers to compete with today, and the budget has not kept up with the growth of the researcher pool competing for funding dollars. Right now, approximately only 16% of grants submitted for federal funding actually get selected for funding. As such, many good grants do not make the cut. 

A long-standing question has been whether federal funding is really going to the research most likely to have an impact in the field, and not just to those who have big labs, a successful history, and work at well known institutions.  What tis question is really asking is, "Does peer review succeed in selecting grants for funding the most impactful research?" Well, until recently science of all things did not have a good answer to this question.  However, a recent study by Li and Agha reported in Science showed that peer reviewers for grants actually do a good job in picking impactful projects, as indicated by publications, patents and other measurable outcomes. 

I recommend to those interested in a very understandable explanation of how grants get selected for funding, and what this research identified to read the attached article in ScienceNews. It is quite insightful, and provides confidence that the system really is working to fund the best research in the various fields of scientific research. The link to the abstract for the actual study published in Science is provided below. On a side note, I think the title is both appropriate and funny for the ScienceNews summary editorial.

Bethany Brookshire. A peer-reviewed study finds value in peer-reviewed research. Science News. April 23rd, 2015.
https://www.sciencenews.org/blog/scicurious/peer-reviewed-study-finds-value-peer-reviewed-research?tgt=nr

Danielle Li, Leila Agha (2015) Big names or big ideas: Do peer-review panels select the best science proposals? Science, Vol. 348 no. 6233 pp. 434-438. DOI: 10.1126/science.aaa0185. 
http://www.sciencemag.org/content/348/6233/434.full

#science   #research   #peerreview   #grants   #sciencenews  

A targeted multi-drug treatment and tracking system may improve human cancer treatment

One of the key obstacles in identifying effective anti-cancer therapies is the lack of translation ability of experimental treatment results to actual tumors in humans. Replicating promising anti-tumor effects observed in animal models of various cancer therapies in humans has proven extremely difficult. This goal is even more challenging when attempting to do so from outcomes and results documented in cell culture experiments. Only approximately 7% of therapies identified in pre-clinical studies are actually approved by the Food and Drug Administration (FDA) to proceed beyond clinical trials for use in human cancer treatment. Costs to develop drugs for human use currently approach nearly 3 billion dollars, which compounds the overwhelming failure of oncotherapies to show effects in humans and further limits progression of cancer-targeting treatments.

Why do so many drugs fail to show benefits in humans while demonstrating promise in pre-clinical experimental studies? A primary contributor to this discrepancy lies in the differences in biology of humans compared to that in experimental conditions. The tumor microenvironment in humans may vary in pH, oxygenation, and other chemical features, and the human immune and inflammatory response can alter the drug's chemical potency or specificity toward tumor cells, or alter the cells’ ability to respond to the treatment. Also, human cancers are often treated, respond, and return, exhibiting some level of chemotherapeutic resistance, which makes recurring cancers harder to treat. It is difficult to model this in an experimental setting. The bottom line is that experimental models do not accurately reflect the human condition. Therefore, improving a therapy’s ability to target human cancers with the desired efficacy and potency while minimizing off-target and unexpected influences of the drug on the body, and vice versa, are critical to advancing cancer therapies for human use. A multi-drug approach is likely going to be a viable answer to overcoming so many issues to get the job done correctly.

A recent study by Klinghoffer et al. in Science Translational Medicine tested a device known as CIVO that is designed to deliver multiple potential therapeutic agents into carefully planned spatial locations within a biological tumor, and utilized paired software to analyze each compound’s effects within the tumor microenvironment. The premise behind such a bioengineering approach is to enhance prediction of the value and efficacy of therapies in pre-clinical animal models, and improve the target specificity, limit unintended side effects, and characterize compound-specific anti-tumorigenic effects in experimental and human cancers. This can help researchers and clinicians predict the potential of one or many compounds for use, as well as serve as a delivery and monitoring device for application in human cancer patients.

Figure 1. CIVO chemotherapy microinjection system diagram. The CIVO system can microinject up to 8 (7 depicted here) therapeutic agents into localized area of a tumor. This allows for analysis of local agent-specific treatment effects as well combined chemotherapeutic agent delivery directly into the tumor, reducing off-target side effects.

The researchers tested the CIVO system, which has the capability to deliver microinjections of up to 8 different drugs into the tumor, in xenograft lymphoma models. Such models involve transfer of human cancers into animals for testing drug efficacy.  Using the CIVO microinjection system, a variety of extensively studied and well-characterized anticancer drugs (vincristine, doxorubicin, mafosfamide, and prednisolone) caused clearly defined localized changes to the biology and structure of cancer cells around sites of drug exposure that were reflective of the previously identified and defined mechanisms of each drug’s effects. Interestingly, these local responses were predictive of responses to systemic administration of the agents in animal models. Perhaps one of the most exciting results of the study identified a new mammalian target of rapamycin (mTOR)-specific inhibitor that exhibited efficacy in killing tumor cells in drug-resistant tumors versus its effects in tumors that had previously not been exposed to any chemical therapy. mTOR is a widely-studied protein in cancer due to its role in enhancing cell growth, protein synthesis, and cell survival - all characteristics of cancer cells that contribute to cancer pathobiology and treatment difficulty. In addition, studies designed to determine the feasibility of the CIVO system for its effects of use in humans and canines showed that the microinjection approach of CIVO highly limited the toxicity of chemotherapeutics while improving the anti-cancer targeting effects. This study is exciting as it combines an engineering approaching with chemotherapeutic delivery and demonstrates the potential to enhance the benefits of chemotherapy in killing tumors while reducing the often-serious toxic side effects inflicted by systemic delivery of such agents. Also, CIVO appears to be a useful experimental system to utilize in pre-clinical studies to better predict the effects of certain drugs, or combinations of drugs, in treating various types of cancer before bringing the therapy to humans. This approach will hopefully bridge the major gap between the results observed in experimental models and the effects documented in human application and advance the treatment of cancer in the very near future.

R. A. Klinghoffer, S. B. Bahrami, B. A. Hatton, J. P. Frazier, A. Moreno-Gonzalez, A. D. Strand, W. S. Kerwin, J. R. Casalini, D. J. Thirstrup, S. You, S. M. Morris, K. L. Watts, M. Veiseh, M. O. Grenley, I. Tretyak, J. Dey, M. Carleton, E. Beirne, K. D. Pedro, S. H. Ditzler, E. J. Girard, T. L. Deckwerth, J. A. Bertout, K. A. Meleo, E. H. Filvaroff, R. Chopra, O. W. Press, J. M. Olson, A technology platform to assess multiple cancer agents simultaneously within a patient’s tumor. Sci. Transl. Med.7, 284ra58 (2015).

#cancer #chemotherapy #doxorubicin #chemoresistant #CIVO #mTOR

Happy Earth Day!

Let us do our best to protect and improve our planet for current and future generations.

#earthday   #earthday2015   #protectourplanet  

Honeybee viruses are a risk for wild bees

Research shows that viruses associated previously with managed honeybees (Apis mellifera) (Figure 1) have now spread to wild bumblebees (Bombus) (Figure 2). Prior studies showed that deformed wing virus had likely transferred from honeybees to wild bumblebees, but researchers at University of London and Queen's University, Belfast identified several interconnected viral diseases that have expanded to affect bumblebees in the wild.

Five viruses in particular were identified from analysis of wild bumblebees and managed honeybees at more than 20 locations across Great Britain: black queen cell virus, deformed wing virus, acute bee paralysis virus, slow bee paralysis virus and sacbrood virus.

Mark Brown of the University of London said, "Our results confirm a recent review of potential threats to pollinators, indicating that so-called honey bee viruses are widespread in wild bees." 

Figure 1. Honeybee (A. mellifera). Central Indiana, 4/2015.

Figure 2. Bumblebee (Bombus). Central Indiana, 4/2015.

"Our findings are important because they indicate that many viruses can spread easily between pollinator species and, furthermore, that they can reach very high disease levels in wild bumblebees," Dino McMahon, from Queen's University, Belfast, added.

These results are of great interest to ecologists and plant-pollinator biologists, as it now appears that transmission of viruses across bee species may occur more frequently and easier than originally thought. Also, wild bumblebees are critical pollinators in the wild and their loss could be detrimental to plant populations dependent on them for pollination.  In addition, as in humans, travel of the bees over long distances could promote widespread infections across bees species in a short amount of time. Further study is necessary, but this initial research highlights the urgency and potential complexity of the situation at hand.

Does anyone with first hand experience with bee-keeping or studying plant-pollinator interactions have any thoughts about this research? What potential implications are there to these findings that may be of importance from a local or regional perspective?

McMahon et al. (2015) A sting in the spit: widespread cross-infection of multiple RNA viruses across wild and managed bees. Journal of Animal Ecology, DOI: 10.1111/1365-2656.12345.
http://onlinelibrary.wiley.com/doi/10.1111/1365-2656.12345/fullhttp://onlinelibrary.wiley.com/doi/10.1111/1365-2656.12345/full

#pollinators   #bees   #honeybee   #bumblebee   #viruses   #ecology   #biology   #science  

Pet dogs trigger a "mother-infant" neurohormonal response

To anyone that has a pet, it's pretty simple to admit they consider their furry companion like a part of the family. You might even call your dog your "little baby", and talk baby talk to it from time to time. It's ok...it's science. Yes, science has now shown that dogs elicit an oxytocin release that is similar to that generated by infants in mothers. Oxytocin is a neuromodulatory hormone that is produced in the hypothalamus of the brain and stored in the pituitary gland. It is released in response to cues of intimacy, trust, and bonding, often as part of our physiological response for involvement in events related to reproduction and in bonding to offspring. Recent research by Nagasawa et al. in the recent issue of Science suggests the gaze of dogs co-evolved with a hormonal feedback loop involving oxytocin in humans as part of the development of the human-dog bond. So, just remember its ok if you think your little "woogums" has the cutest furry little face ever. Science says that's what how you are supposed to feel.

Miho Nagasawa, Shouhei Mitsui, Shiori En, Nobuyo Ohtani, Mitsuaki Ohta, Yasuo Sakuma, Tatsushi Onaka, Kazutaka Mogi, Takefumi Kikusui, Oxytocin-gaze positive loop and the coevolution of human-dog bonds. Science, 17 April 2015; 348(6232):333-336 
DOI: 10.1126/science.1261022.

Traumatic brain injury "ages" your brain

As if having a traumatic brain injury (TBI) is not bad enough, recent clinical research suggests it "ages" your brain relative to you true chronologic age. A new study by Cole et al. Annals of Neurology found that TBI-induced brain aging not only causes your brain to exhibit anatomical and functional defects associated with an aging brain, but that the effects are more pronounced the farther out you go from time of injury. In other words, this "aging" process seems to accelerate as one with TBI gets older. 

As quoted from the study's abstract:
"TBI brains were estimated to be 'older,' with a mean predicted age difference (PAD) between chronological and estimated brain age of 4.66 years (±10.8) for GM (gray matter) and 5.97 years (±11.22) for WM (white matter = myelinated axon tracts).

What processes were defined as similar to those observed in the aging brain?

Animal research has implicated a number of biological and pathological processes that affect tissue damage at the time of injury, and progressing even after the initial mechanical tissue damage. Multiple mechanisms such as chronic neuroinflammation, degeneration of damaged axons, and accumulation of pathological tau and amyloid-β proteins often associated with neurodegenerative disease like Alzheimer's disease have been reported. Ultimately, these events cause changes in cell structure and function, cell death, and brain atrophy. These processes often occur simultaneously, while others continue chronically while others subside. Is this really a case of the brain "aging" faster than the body that contains it? It is hard to say. It is also hard to say how true aging that coincides with the progressions of neuropathology interact or influence these processes. Nevertheless, this study yields interesting clinical insights into human responses and outcomes that have long been studied in animal models. It also poses questions to ponder concerning the connections between trauma-induced neurodegeneration, and age-induced or gene-induced neurodegeneration. An interest step in clinical neurodegenerative research, but much more research is needed to fully flesh out answers to questions these results present.


JH Cole PhD*, R Leech PhD, DJ Sharp PhD and for the Alzheimer's Disease Neuroimaging Initiative. (2015) Prediction of brain age suggests accelerated atrophy after traumatic brain injury. Annals of Neurology 77(4): 571-581.