Biology Online is a Biology blog and dictionary site that provides up to date articles on the latest developments in biological science. The Biology Online Dictionary is a completely free and open dictionary with over 60,000 biology terms. It uses the wiki concept, so that anyone can make a contribution.

Category: Research

CRISPR DIY – biohacking genes at home

Have you ever thought of changing yourself for the better — genetically-speaking? Lately, CRISPR company has been selling a CRISPR DIY, i.e. a gene-therapy kit purchasable online. Thus, you could biohack and strike genes at your convenience, practically whenever and wherever — even right at the comfort of your home.



CRISPR – a scientific breakthrough

CRISPR would not be considered as Science’s Breakthrough of the Year in 2015[1] for nothing. Previously, I wrote a blog how mosquitoes could be wiped out by CRISPR–Cas9 gene drive. I delineated how CRISPR could serve apparently as our “last resort” against one of the deadliest animals on Earth, the mosquitoes.


We all know these miniscule mosquitoes could pose a huge threat on the lives of many. They are deadly not because they can directly kill us but because they are harbingers of pathogens of medically-important diseases such as malaria, dengue fever, Zika diseaselymphatic filariasis, yellow fevertularemia chikungunya,  and several forms of encephalitis. Recently, researchers identified mosquitoes as carriers of Keystone virus and the pathogen of Rift Valley fever as well.


In effect, researchers from around the globe have constantly sought for a way to mitigate the disease-transmission spree of these deadly blood-suckers. Just last year, scientists from Imperial College London came up with a means to destroy mosquitoes — by biohacking their DNA using CRISPR technology. Using CRISPR–Cas9 gene, the scientists suppressed the population of caged Anopheles gambiae mosquitoes (human malarial vector).


In brief, they modified the gene responsible for determining sex in male mosquitoes and turned the male gene dominant. Then, they added these “hacked’ mosquitoes to a caged population of unaltered male and female mosquitoes. As a result, the next generations of females could no longer lay eggs and could not bite. And then by the eight generation, the population no longer had females [2].



Doing it the CRISPR way

CRISPR (acronym for Clustered Regularly Interspaced Short Palindromic Repeats) is a gene-hacking tool of bacteria. Hence, we can say that these bacteria are the original biohackers. They use it as a tool to protect themselves from re-invading bacteriophages, similar to our immune system’s adaptive immunity. The gene-hacking tool of bacteria makes use of gRNA and Cas9 enzyme. While gRNA binds to the target DNA, Cas9 cuts the DNA target to disable it. Now, scientists exploit it as a way to splice specific DNA targets and then replace them with a DNA that would yield the desired effect. For instance, CRISPR can correct physiological anomalies caused by gene mutations or defective genes.[3]



First clinical trials

With the potential to treat thousands of genetic disorders, CRISPR has now been making a huge step towards becoming a legitimate, doctor-prescribed treatment. In 2016, US FDA approved the clinical trial study wherein CRISPR technology was used to treat patients with cancers.[4] Apparently, CRISPR can switch off a gene in immune cells or hack their genes to boost them into combating cancer. Hence, it has the potential to cure certain cancers.


Furthermore, CRISPR seemingly can treat people with inherited blindness. In essence, researchers look through it by injecting it into the patient’s eye with the intent that it will snip out the mutation. If successful, it could be used to treat a wide variety of genetic disorders, such as Duchenne muscular dystrophy, cystic fibrosis, and so on.[5]


According to the bioethicist, Laurie Zoloth from the University of Chicago Divinity School, CRISPR is allowed to be done in clinical trials for these genetic conditions because it is believed not to cause heritable DNA changes. However, precautionary measures are still warranted.[5]



CRISPR DIY biohacking


CRISPR DIY kit. (Image credit: Sylvia Fredriksson, Flickr, CC by 2.0)


Aside from its medical potentialities, CRISPR has many other applications. Scientists eye its use in producing more resilient crops, in making biofuel, reviving extinct species, creating new ones, and so on. The fact that living things are in essence made up of genes then the usage of CRISPR could only be limited by one’s imagination. There is even a concern over its use as a means for an ethically-refuted purpose. That is by creating new species designed for biological weapon poised as a treatment that could be purchased online. It might be a stretch. However, the possibility remains.


As noted earlier, its breadth of use is as far as where one’s imagination can reach, especially now that a CRISPR lab kit can now be easily obtained, i.e. simply by ordering online for just under $150.[6] It comes with the instructions. So in an instant, you can become a biohacker, capable of re-engineering DNA at home, with the added benefit of doing it away from the prying eyes of anybody.


CRISPR is undeniable a breakthrough and poises to be the most-promising medical cure of the millennium. It could be the straight answer we need to resolve many genetic problems. However, we should not be too hasty. Care should be taken in utmost regard to make sure that no ethical issues and caveats over potential dangers are left unheeded.




— written by Maria Victoria Gonzaga





1  Science News Staff. (2015). And Science’s 2015 Breakthrough of the Year is… Retrieved from [Link]



3  Gonzaga, M. V. (2018). CRISPR caused gene damage? Rise and pitfall of the gene-editor. Retrieved from [Link]

4  Reardon, S. (2016). First CRISPR clinical trial gets green light from US panel. Retrieved from



5  Saey, T. H. (AUGUST 14, 2019). CRISPR enters its first human clinical trials. Retrieved from [Link]


6  Al-Ghaili, H. (2019). DIY CRISPR. Retrieved from [Link]

Hallucination – Are we the only ones “seeing” things or animals hallucinate, too?

Hallucination is defined as perceiving something that seems real but in fact it is not. Some references take it as a synonym for delusion. Both hallucination and delusion are a perception or belief that something seems real. However, the individual that experiences hallucination senses a vision, sound, or other perceptions later on denies it to be real based on evidence or logic. People with delusion, in contrast, believe something as real in spite of refuting evidence.  

Hallucinations – a brain glitch – apparently could occur in animals, too. At least, according to a recent experiment on lab mice using optogenetics technique. [Img credit: Rick Harris (Flickr), by CC BY-SA 2.0]

Common causes of hallucination

Hallucination does not occur frequently. Nonetheless, it could be a common experience in individuals suffering from mental disorders like schizophrenia. Accordingly, >70% of those suffering from schizophrenia experience visual hallucinations whereas 60-90% believe they heard voices.[1] Additionally, other conditions that result in hallucinations include certain cases of Parkinson’s disease, Alzheimer’s disease, migraines, brain tumor, and epilepsy. Apart from these conditions certain medications – called “hallucinogens”  — have also caused hallucinations. For example, “Lysergic acid diethylamide” drug causes hallucination, in particular, by acting on serotonin (5-hydroxytryptamine [5-HT])-receptors.

High caffeine intake was also implicated to hallucinations. Accordingly, people who drink more than seven cups of instant coffee in a day turned out to be three times more likely to “hear voices” than those who drink less.[2] In this case, scientists explicated that high caffeine intake led to an increased cortisol (a stress hormone), which, in turn increased proneness to hallucinate.

People experiencing hallucinations may feel afraid from the perceptual experience. Seeing a vision like a seemingly floating light, hearing sounds like footsteps, or a crawling feeling on the skin that later on are construed as not real could really be scary.  

Neurobiological factors

Why does hallucination occur? In essence, hallucinations involve defects in the structure and function of the primary and secondary sensory cortices of the brain. In the case of Alzheimer’s disease, visual hallucinations are associated with grey and white matter abnormalities. “Seeing”, “hearing”, or “feeling” things is by chance spontaneous and also a transitory personal experience. Thus, understanding the biological phenomenon of hallucination remains a challenge to neurobiologists and scientists alike to this day.

Do animals hallucinate?

Do animals hallucinate, too? Scientists can hardly tell but studies implicate animal models such as lab mice making a head-twitch response (a hallucinatory behavior) when administered with hallucinogen.[3] However, some scientists argue it was not a compelling proof of such animals hallucinating.

Recently, though, a team of researchers from Stanford Medicine claim that they made lab mice hallucinate without injecting hallucinogen. Instead, they made use of optogenetics technique. In this case, they inserted light-sensitive genes into their brain. As a result, certain neurons tend to fire with particular light wavelengths. The genes would produce two types of proteins: one, causing neurons to fire when exposed to infared laser light and another, causing neurons to glow green when activated.[4]

The scientists, then, trained the mice to lick a water spout when exposed to a pattern of moving parallel lines (i.e. perfectly vertical or horizontal lines). Based on the green glow response of the visual cortex, the scientists knew which neurons were firing, thus responding. These neurons supposedly were the ones responsible for “seeing” the pattern of lines. [4,5]

Gradually, researchers dimmed the projections while triggering the target neurons with their special laser. Eventually, they stopped showing the line patterns and yet the mice would still lick the water spout when scientists hit the same target neurons with laser. The result therefore implies that the mice might have experienced “true hallucination”, seeing “ghost” line patterns.[5]

— written by Maria Victoria Gonzaga


1  Fowler, P. (2015, August 27). Hallucinations. Retrieved from WebMD website: Link

2  Durham University. (2009, January 14). High Caffeine Intake Linked To Hallucination Proneness. ScienceDaily. Retrieved from Link

3  Can animals have hallucinations? – Quora. (2018). Retrieved from website: Link

4  Stanford Medicine. (2019, July 18). Scientists stimulate neurons to induce particular perceptions in mice’s minds. ScienceDaily. Retrieved from Link

5  Specktor, B. (2019, July 19). It’s a Mystery Why We Are Not Constantly Hallucinating, Trippy New Study Suggests. Retrieved from Live Science website: Link

Genetically “curing” an infertile crop plant into fertile again

Plant geneticists from the University of Tokyo are onto creating novel plant lines that seem to be “more polite” than they already are.1,2,3 However, their technique does not involve implanting a “social” gene of some sort. Rather, scientists would edit plant mitochondrial DNA. In that way, they can, for instance, make a plant bow down even more due to the heavier seeds it would yield. Thus, this could mean a more secured food supply. More interestingly, this genetic modification was accordingly the first time ever to be done on a plant mitochondrial DNA.

Mitochondrial DNA

Mitochondria are one of the three organelles containing nuclear material. The nucleus and the chloroplast are the other two. Scientists have already done successful modifications of the nuclear DNA since1970s. Then, another team of researchers pioneered modification of chloroplast DNA in 1988. However, in terms of mitochondrial DNA, researchers had only found success on animals but not on plants. The first successful animal mitochondrial DNA modification happened in 2008. Then recently, a team of researchers from the University of Tokyo apparently showed success in doing it as well on a plant mitochondrial DNA. In this case, this was the first time.

Basically, mitochondrial DNA is the genetic material in the mitochondrion that carries code for the manufacturing of RNAs and proteins essential to the various functions of the said organelle. Since a mitochondrion has its own genetic material it is described as a semi-autonomous, self-reproducing organelle.

First plant mitochondrial DNA modification

Researchers from the University of Tokyo devised genetic tools that can edit plant mitochondrial DNA. Accordingly, they came up with four new lines of rice and three new lines of rapeseed (canola) using their technique. Between plant and animal mitochondrial genes, those in plants are larger and more complex. Prof. Arimura explicated that plant mitochondrial genes are more complicated in a way that some mitochondria have duplicated genes whereas others lack them. Thus, manipulating plant mitochondrial genome proved more challenging. Their collaboration with other researchers, particularly from Tohoku University and Tamagawa University, led them to their use of the technique mitoTALENs. With it, they were able to manipulate mitochondrial genes in plants.1 To learn their methods in detail you may read their published work here.

The plant mitochondria rapidly moving around the cell (Arabidopsis leaf epidermal cell). Artificially made to glow green to show their actual speed. Video by Shin-ichi Arimura CC-BY

What plant mitochondrial DNA modification can do

After the successful editing of plant mitochondrial DNA, what could be the next big thing? Associate Professor Shin-ichi Arimura, leader of the research team, was enthusiastic indeed about their accomplishment. With a jest, he said, “We knew we were successful when we saw that the rice plant was more polite — it had a deep bow” – implying that a fertile rice plant would bend more due to the heavier weight of the seeds it would yield.1,3

A weak genetic diversity in crops could impose a threat to species survival through time. As a domino effect, that is bad news to our food supply.  Thus, their team hope to use their technique by providing solutions that could significantly enhance genetic diversity in crops, and therefore improve plant species survival and yield. Arimura further said, “We still have a big risk now because there are so few plant mitochondrial genomes used in the world.”1 Furthermore, he mentioned of using their technique for the purpose of adding the much needed mitochondrial DNA diversity among plants.

Cytoplasmic male sterility

plant mitochondrial DNA modification technique
Plant mitochondrial DNA modification technique to enhance crop yield and genetic diversity

Cytoplasmic male sterility (CMS) refers to the male sterility in plants by not producing functional pollen, anthers, or male gametes. It occurs naturally although rarely and probably involve certain nuclear and mitochondrial interactions.4 Nonetheless, others believe that CMS is caused primarily by plant mitochondrial genes.1  In particular, the presence of CMS gene leads to this condition in plants. Thus, removing the CMS gene could convert the plant into becoming fertile again. This is just a start but they are already optimistic that with their technique they could improve crop lines and consequently secure food supply.

plant mitochondrial DNA modification
A mitochondrial gene that causes cytoplasmic male infertility was deleted using a mitoTALENs technique. Infertile rice (right) stands straight, but fertile rice (left) bends under the weight of heavy seeds. Image by Tomohiko Kazama, CC-BY

— written by Maria Victoria Gonzaga


1 University of Tokyo. (2019, July 8). Researchers can finally modify plant mitochondrial DNA: Tool could ensure genetic diversity of crops. ScienceDaily. Retrieved from [Link]

2 Arimura, S. -i., Yamamoto, J., Aida, G. P., Nakazono, M., & Tsutsumi, N. (2004). Frequent fusion and fission of plant mitochondria with unequal nucleoid distribution. Proceedings of the National Academy of Sciences101(20), 7805–7808. [Link]

3 Researchers can finally modify plant mitochondrial DNA | The University of Tokyo. (2019). Retrieved from The University of Tokyo website: [Link]

4 Campo, C. (1999). Biology of Brassica coenospecies. Amsterdam New York: Elsevier. pp.186-89.

RASER proteins selectively “hack” and “shut down” cancer cells

According to World Health Organization, cancer is the second leading cause of death worldwide. The record showed that it caused about 9.6 million deaths last year (2018). Accordingly, one in every six deaths is attributed to cancer.[1]

Cancer defined

Cancer refers to the disease that arises from the faulty uncontrolled proliferation of cell, usually at a rate faster than the normal, and spread to other parts of the body. Benign tumors are also a form of atypical cell proliferation. However, the latter does not spread.

Pathophysiology in cancer cells

Why cancer cells lead to a disease is largely due to the tendency of the cancerous cell to detach and leave its original location to set itself to another site in the body. It could spread locally or drift through the bloodstream and lymphatic system to reach distant parts of the body. As a result, the affected body part eventually cannot carry out its function as it normally would due to the obstructing cancer cells that ought not to be there in the first place. Under those circumstances, our immune system is fashioned to detect cells that have gone “rogue” and then respond by eliminating them accordingly. Nevertheless, cancer cells tend to undergo series of mutations until such time that the genes for tumor suppression have been significantly inactivated while the proto-oncogenes modify into oncogenes.

RASER proteins

A novel approach dubbed as RASER (Rewiring of Aberrant Signaling to Effector Release) showed promising results when it killed cancer cells grown in the lab while sparing non-cancerous healthy cells. Researchers from Stanford Medicine[2] designed RASER system, which, in essence, consists of two proteins fused together. Accordingly, the first protein responds to cancer-causing cell surface signals. It does so by binding to active ErbB receptors, which are always “on” (expressed) in cancer cells. The second protein redirects the cancer cell from cell growth and survival toward programmed cell death (by releasing a customizable “cargo” into the cell). When the first protein binds to an active ErbB receptor, the second protein component is cut off from the RASER moiety and then binds to the inner surface of the plasma membrane of the targeted cell. The researchers customized the “cargo” sequence that the second protein carries. Once inside the cell, the second protein releases the RASER “cargo” — in this case, one that triggers the cell to undergo cell death.[2]

Top:  Illustration of cancer growth where cell surface proteins signal the nucleus to proliferate uncontrollably and survive (see green pathway). Bottom: Illustration of how RASER works by redirecting the signal away from cell proliferation and survival toward programmed cell death (see orange pathway). Image credit: Michael Lin and Stuart Jantzen (Ref.2)

One of the researchers, Michael Lin, MD, PhD, said that with this new approach they could rewire cancer cells and bring about an outcome according to their choosing. Furthermore, he said, “We’ve always searched for a way to kill cancer cells but not normal cells. Cancer cells arise from faulty signals that allow them to grow inappropriately, so we’ve hacked into cancer cells to redirect these faulty signals to something useful.” [2]

Although it could take time, still, the conception and the future progress of RASER is an auspicious cancer treatment. In due course, cancer patients may reap from its stance of being more highly selective to cancer cells while sparing the healthy ones in which the current cancer treatments are failing at.

— written by Maria Victoria Gonzaga


1 World Health Organization (WHO). (2018, September 12). Cancer. Retrieved from website: [Link]

 2 Conger, K. (2019). Synthetic biology used to target cancer cells while sparing healthy tissue. Retrieved from News Center website: [Link]

Scientists brought dead pig brain partly back to life

Death is inevitable to any entity that has life. When there is a beginning there ought to be an end.  However, the recent findings of a team of researchers seemed to paint a gray line between what’s supposedly dead and what’s alive. Accordingly, they were able to restore certain functions on pig brains that had been dead for hours and were essentially isolated from the body. Does it mean resurrecting a dead brain could eventually be made possible by science?

Bringing a dead brain back to life

A research team conjured up a special chemical liquid that apparently restored some of the functions of dead pig brains. They isolated the brain from the heads of post-mortem pigs. The researchers then hooked up the device pumping the concoction for six hours through the blood vessels of the dead brain. They used 32 pigs that had been dead for about four hours after being slaughtered (for food). 1 As such, the pig brains were bereft of circulating blood and glucose for four hours prior to the treatment.

The research team discovered that the pig brains that received the treatment looked different from the pig brains that did not (controls). Apparently, the tissues and cell structures of the treated pig brains appeared preserved. Moreover, certain cellular functions seemed restored.

The resurrecting BrainEx

The patented chemical solution (a perfusate) was delivered by a pulsatile-perfusion system (referred to as BrainEx2). The authors described the perfusate as hemoglobin-based, acellular, non-coagulative, cytoprotective, and echogenic.3 In essence, the system was contrived to mimic blood circulating through the organ. Thus, its role is to rehydrate the post-mortem pig brains, at least for six hours. The results were indeed astounding. The dead brain had some of the basic cell functions restored. ‌

The authors attributed the following effects3 to the BrainEx system:

  • recovery from anoxia
  • edema prevention
  • reduced reperfusion injury
  • metabolic support to the brain’s energy demand
  • preservation of cell structure
  • attenuated cell death
  • revived blood vessel structure
  • localized synaptic activity and glial immune response

The authors, though, noted that they had not observed any higher level functional activity, like electrical signaling that normally would indicate consciousness.

Immunofluorescent staining of dead brains of pig
Immunofluorescent stains of the post-mortem pig brain “un-perfused” (left) vs. that perfused with BrainEx technology (right). After ten hours post-mortem, neurons (green) and astrocytes (red) of the dead brain underwent cellular disintegration unless salvaged by BrainEx (Ref: 4). [Credit: Stefano G. Daniele & Zvonimir Vrselja; Sestan Laboratory; Yale School of Medicine]


The brain exposed to hypoxic condition for even a few minutes could end up suffering an irreparable damage. In fact, the human brain can survive oxygen deficiency as long as the oxygen supply is swiftly restored idyllically within about six minutes. Otherwise, the brain will start to die. With this recent breakthrough, this means that a dead brain may have its functions restored. Nenad Sestan, the lead author, was quick to point out though that the brain administered with the perfusion was revived not as a living brain per se but as a “cellularly active brain”1. Nonetheless, the research team believed that their findings could one day find its invaluable use in helping out victims of brain trauma, strokes and heart attacks. These life-threatening conditions could abruptly cut blood flow and oxygen supply leading to brain injuries considered as irreversible, even fatal. This revolutionary finding, now, gives hope.

human brain photo by Rev314159 flickr
Human brain. [Credit: Rev314159, Flickr, by CC BY-ND 2.0]

Ethical issues

In spite of the promising breakthrough in neuroscience and medicine, their findings trigger ethical concerns. Could this be the start of resurrecting the dead? Stephen Latham, from Yale’s Centre of Bioethics and one of the authors, reassured, “If some activity shows up that indicated consciousness, we would have to stop the experiment”.5 They made it clear that they did not intend to awaken consciousness. And, if inadvertently they did so they would immediately resort to anesthetics and temperature-reduction in order to stop electrical signaling as soon as it emerged. Still, they hope to gain insights involving post-mortem human brains. All the same, they will only do so within the confines of utmost ethical considerations.

— written by Maria Victoria Gonzaga


1  Scientists Restore Some Function In The Brains Of Dead Pigs. (2019, April 17). Retrieved from website: [Link]

2   Ranosa, T. (2019, April 19). Are We Close To Resurrecting The Dead? Scientists Revive Brain Cell Activities In Dead Pigs. Retrieved from Tech Times website: [Link]

3    Vrselja, Z., Daniele, S. G., Silbereis, J., Talpo, F., Morozov, Y. M., Sousa, A. M. Mario, S., Mihovil, P., Navjot, K., Zhuan, Z. W., Liu, Z., Alkawadri, R., Sinusas, A. J., Latham, S.R., Waxman, S. G., & Sestan, N. (2019). Restoration of brain circulation and cellular functions hours post-mortem. Nature568(7752), 336–343. [Link]

4  Yale University. (2019, April 17). Scientists restore some functions in a pig’s brain hours after death. ScienceDaily. Retrieved from [Link]

5   Researchers Restore Some Function To Brains Of Dead Pigs. (2019, April 17). Retrieved from website: [Link]

FAAH-OUT mutation for a life of no pain – No FAAH, no pain

A Scottish woman claims that she has not experienced pain over some supposedly painful conditions, like a severe joint degeneration or a post-operation she underwent for her hand due to osteoarthritis. Accordingly, she never needed painkillers and her case astounded doctors.

A baffling case

Doctors were baffled when the 71-year old Scottish woman, Jo Cameron, came to seek treatment for her hip problem six years ago (at age 65). Astonished, the doctors found out that her joint severely degenerated and by that they expected her to experience excruciating pain just as a typical person would. However, she showed no signs of discomfort over it. Furthermore, she said that at age 66 she underwent a supposedly painful operation on her hand due to osteoarthritis yet felt no pain after. According to the news1, Cameron was not aware at first for feeling virtually no pain over such situations. Purportedly, she thought that what she felt (i.e. lack of a thwarting pain) was normal. She later learned about her lack of pain and the plausible reason only recently.


Researchers went on to see what caused Cameron’s bizarre lack of pain. They suspected that her genes could shed light to her case. Hence, they analyzed her genes. Subsequently, they found mutations, thereby, affirming their hunch. According to their genetic analyses2, Cameron had two mutations: (1) a microdeletion in a pseudogene and (2) a mutation in a nearby gene controlling the enzyme fatty acid amide hydrolase (FAAH).2

The pseudogene was only partly annotated in the medical literature. Thus, researchers describing the gene and subsequently calling it FAAH-OUT was a first. Previously thought of as a “junk gene”, FAAH-OUT could probably be more than that. It likely regulates FAAH expression as postulated by the research team.2 Consequently, they now look upon how it works.

FAAH gene

With regard to the FAAH gene, researchers know this gene encodes for the FAAH enzyme involved in endocannabinoid signaling. In essence, FAAH normally degrades anandamide (a fatty acid neurotransmitter) into free arachidonic acid and ethanolamine. Thus, without FAAH, the levels of anandamide would increase significantly. This, in turn, leads to a reduced pain sensation, as observed in FAAH knockout mice.3 FAAH knockout mice demonstrated not only the absence of pain but reduced anxiety and faster wound healing as well.2,3

Likewise, Cameron purportedly exhibits similar traits. According to her, she never panics (even in dangerous situations), has no fears, and is immune to anxiety. She would also have bouts of cuts and burns in which she would not notice sometimes albeit her injuries would heal very quickly.2 The tests revealed that she had elevated levels of anandamide – an indication of a lack of FAAH function.2

Novel pain treatment targets

FAAH-OUT gene mutation
Mutation in FAAH-OUT gene resulted in more anandamides, which in turn leads to feeling of no pain, reduced anxiety, and quick wound healing. [Photo by juan mendez from Pexels]

One of the lead researchers of the study, Dr. James Cox, said that Cameron has a genotype that reduced gene activity. Cox and his research team are optimistic that their discovery could possibly lead to novel pain and anxiety treatments that target this newly-identified gene.2 Their findings might lead to novel strategies that would eventually help patients suffering from severe pain despite receiving advance pain killer medications.

— written by Maria Victoria Gonzaga


1 Hunt, K. (2019 March 28). “Woman who feels no pain could help scientists develop new painkillers”. Retrieved from CNN website [Link]

2  University College London. (2019 March 27). “Woman with novel gene mutation lives almost pain-free”. Retrieved from Eureka website [Link].

3 Cravatt, B.F., Demarest, K., Patricelli, M.P., Bracey, M.H., Giang, D.K., Martin, B.R., & Lichtman, A.H. (2001). “Supersensitivity to anandamide and enhanced endogenous cannabinoid signaling in mice lacking fatty acid amide hydrolase”. Proceedings of the National Academy of Sciences of the United States of America, 98 (16): 9371–6. 

Regeneration in humans – Finding the gene switch

Regeneration in humans is much more limited compared in other animals. Say for instance when one lost a limb, much as well say goodbye to it for the rest of one’s life. Perhaps, it would be nice if we have higher capacity to regenerate many of our indispensable body parts, like head, limbs, and many other “regeneration-incapables”. Then probably, we might not have to worry much about losing any of them knowing that they will eventually re-grow in due time.



Regeneration vs. Healing

Humans have the capacity to regenerate. However, we have a very limited capabiltiy to restoring parts of our skin, hair, nails, fingertips, and liver. At the tissue level, surely we have dedicated cells to replace lost and damaged cells. For instance, our non-injured bone eventually replenishes into a full new bone but in a span of ten years. Our skin naturally renews but give it two weeks. The story swerves differently though in the case of an injury.


Rather than expending energy into having it replaced with a new one, our body directs its efforts into healing it. So when our skin is deeply damaged, our body fixes it with a scar. Tissue repair mechanisms such as wound healing aren’t really a snag. They forestall pathogenic microbes from using an injured body part as an easy gateway into our body. (Besides, we do have ample microbiota naturally thriving inside of us already) The main goal is to fix it efficaciously, with relatively less effort.




Natural regeneration in humans

In humans, the only tissue that regenerates naturally, consistently, and completely is the endometrium.1 After it slough-offs during a woman’s menstrual period, it grows back by re-epithelialization until the next period. Humans can also regenerate an injured liver provided that the restoration involves as little as 25% of the original liver mass. The liver can grow back to its original size but may not to its original shape. Damaged tubular parts of the kidney can also re-grow. The surviving epithelial cells undergo migration, dedifferentiation, proliferation, and re-differentiation to set a new epithelial lining of the tubule.




Animals with higher regeneration capacities


axolotl regeneration
Axolotl (Ambystoma mexicanum) is one of the animals dubbed as masters of regeneration. It can grow back its limbs, even a heart, without a scar. [Photo credit: Mike Licht, Flickr]


Some animals have higher capacity to re-grow lost body parts. Sharks, skates, and rays can regenerate their kidneys. They can regrow an entire nephron, which humans cannot. A lizard would drop its tail as a mode of escape; its tail will be fully restored over time anyway. Sharks do not have qualms about losing teeth. They can replace any of them more than a hundred times in their lifetime. Axolotl can replace its broken heart. A starfish will once again be stellar upon the return of a lost arm. In fact, even its lost arm can fully regenerate into an entire starfish as long as the central nerve ring remains intact.2 A decapitated planarian worm needs not worry about losing its head; it can grow back, together with its brain, including the memories.2 Without a doubt, many of these animals are simply masters of their craft – regeneration.



Regeneration genes

Researchers from Harvard University published their new findings on whole-body regeneration capacity of the three-banded panther worm.3 They uncovered DNA switches that seemed to regulate genes that have a role in the regeneration process. Accordingly, they found a section of a non-coding DNA that controlled the activation of a master gene in which they called the “early growth response” (EGR) gene. When active, the EGR gene seemed like a power switch that turns on and off certain genes in the coding region during regeneration. On the contrary, when deactivated, no regeneration occurred.


Surprisingly, humans have EGR gene, too.  So why doesn’t it lead to greater regeneration capacities as it does in the three-banded panther worm? The researchers explained that while it works in the worm, it doesn’t work the same way in humans. The wiring may be different. The worm’s EGR gene may have germane connections that are absent in humans.




Switching the gene on

Regeneration in humans
Regeneration in humans is limited. If only we knew the switch that could amplify our regeneration capacity then we might not have to worry much about losing a body part. [Photo credit: Pete Johnson, Pexels]


Induced regeneration in humans is one of the goals of regenerative medicine. This field of medicine seeks new ways to give our regenerative capacity a boost. One of the ways is to look “molecularly”. Researchers are looking into the gene “Lin28a“. When active, this gene can reprogram somatic cells into embryonic-like stem cells. Accordingly, it has a role in tissue regeneration and recovery. However, the gene is naturally turned off in adults. Research in boosting our regenerative capacities is ongoing. Switching our organs from being regeneration-incapable to regeneration-capable may just be a matter of discovering the gene switch that could enhance regeneration capacity of humans.



— written by Maria Victoria Gonzaga




1 Min, S., Wang, S. W., & Orr, W. (2006). “Graphic general pathology: 2.2 complete regeneration”Pathology. Retrieved from [Link]

2  Langley, L. (2013, August 28). “Pictures: 5 Animals That Regrow Body Parts”. National Geographic News. Retrieved from [Link] ‌


Fasting boosts human metabolism, has anti-aging effects

In the advent of 2019, we are inspired to set new goals, pursue life-long dreams, or simply make better choices. Perhaps, one of the most common reveries we wish to realize is to be able to adopt a healthier kind of lifestyle. With this in mind, some of us look for ways to feel dutifully healthier, such as by managing our weight. So, many would turn to fad diets and caloric restrictions that promise to help. One of them is intermittent fasting. Based on studies, intermittent fasting does not only help trim weight but it seems to offer further health benefits as well.




Intermittent fasting – overview


intermittent fasting
Scientists found that fasting boosted human metabolism. This could mean that fasting may slow aging in humans. [Image credit: Zeyus Media]



In May 2018, I wrote the article: Intermittent Fasting – benefits and caution. There, I tackled briefly about intermittent fasting, its benefits, and potential risk. In essence, intermittent fasting is a cyclic pattern of a period of fasting and a subsequent period of non-fasting. The most common forms are: (1) whole-day fasting and (2) time-restricted eating. Whole-day fasting entails one-full day of “no eating”, done twice a week (thus, referred to as “5:2 plan“). In time-restricted eating, there is an interval of fasting and non-fasting on a daily basis. It could be half a day of fasting, and then the remaining half as the non-fasting period.  With intermittent fasting, it’s not so much about “what to eat…” or “how much…” Rather, it’s more about a question of when.




Intermittent fasting became popular because it does not only help curb weight but it also implicates other health benefits. It apparently slows aging and boosts the immune defense.[1] However, as I pointed out in that article, caution should still be taken. Intermittent fasting is not for everyone, especially those who are immunocompromised and underweight.[2]




Rejuvenating effects of fasting

Previously, I mentioned that studies confirming the health benefits of fasting were done on non-human subjects (e.g. rodent models). Without much scientific proofs of efficacy on humans, what would, therefore, be definite is doubt.  However, on January 29 of this year, a team of scientists from Okinawa Institute of Science and Technology Graduate University (OIST) and Kyoto University reported rejuvenating effects of fasting on human subjects. They published their findings in Scientific Reports.[3] Accordingly, they analyzed the blood samples from four fasting individuals. They also monitored the levels of metabolites involved in growth and energy metabolism. What they found was quite interesting and promising.




Dr. Takayuki Teruya, one of the researchers of the team, said that their results implicated the rejuvenating effects of fasting. They found that many metabolites increased significantly, about 1.5- to 60-fold, in just 58 hours of fasting. In their previous study, they identified some of these metabolites (e.g. leucine, isoleucine, and ophthalmic acid), that typically deplete with age. According to Dr. Teruya, they found that the amount of these metabolites increased again in individuals who fasted. Also, they conjectured that fasting could possibly promote muscle maintenance and antioxidant activity based on the metabolites they found. Hence, fasting may probably promote longevity as well. Dr. Teruya further said that this was not yet known until now since most studies that have said so used animal models.[4]




Fasting increased metabolism

During fasting, the body turns to alternate energy stores when carbohydrates are not available. Thus, the less-common metabolites from alternative metabolic pathways superseded the typical metabolites from carbohydrate metabolism. They identified butyrates, carnitines, and branched-chain amino acids as some of the metabolites that accumulated during fasting. [4] Apart from this, the researchers also found an increase in Citric acid cycle intermediates. This means that aside from prompting alternate metabolic pathways, fasting has also augmented the common metabolic activities. The metabolism of purine and pyrimidine seemed also heightened, indicating an increase in gene expression and protein synthesis. Because of this, the researchers also saw a boost in antioxidants (e.g. ergothioneine and carnosine) that protect cells from the free radicals produced by metabolism. The researchers assume to be the first to provide evidence of antioxidants as a fasting marker. [4]




This new-found proof infers that fasting seems to have some anti-aging effects, this time, on human subjects. Their next step is to see if they could duplicate the results in a larger-scale study. For now, let us remain cautious, look for indubitable substantiation, and weigh in the benefits and risks of all available options.




— written by Maria Victoria Gonzaga





1  Cohut, M. (2018). Intermittent fasting may have ‘profound health benefits’. Retrieved from [Link]

2  Longo, V. D., & Mattson, M. P. (2014). Fasting: Molecular Mechanisms and Clinical Applications. Cell Metabolism, 19 (2), 181–192. [Link]

3 Teruya, T., Chaleckis, R., Takada, J., Yanagida, M. & Kondoh, H. (2019). Diverse metabolic reactions activated during 58-hr fasting are revealed by non-targeted metabolomic analysis of human blood. ”Scientific Reports, 9”(1) DOI: 10.1038/s41598-018-36674-9.

4  ‌ Okinawa Institute of Science and Technology (OIST) Graduate University. (2019, January 31). Fasting ramps up human metabolism, study shows. ScienceDaily. Retrieved from [Link]

On Mate Selection Evolution: Are intelligent males more attractive?

A study published in Science on January 11 seems to be the first to lay empirical evidence that concur with Charles Darwin’s hypothesis: … that mate selection might have contributed to the evolution of intelligence or cognitive abilities. Scientists from China and the Netherlands collaborated in a study on budgerigars, Melopsittacus undulatus. Based on what they observed, problem-solving skills apparently increased the attractiveness of male birds. Accordingly, female birds chose to spend more time with male birds that appear to be smarter.[1]



Darwin on mate selection

In animal kingdom, mate selection is a real deal. One of the generalized traits that distinguish the animal from the plant is the former’s tendency to select a mate. Animals, including humans, have their set of preferences when it comes to choosing a mate. While plants chiefly let nature do the “selection” for them, animals tend to seek a potential mate by themselves. And when they find a suitable mate of their choice, they often make a conscientious effort to succeed at coupling. In particular, males engage first in a courtship ritual, for example, by wooing a female with a song, a dance, or by a display of beauty or prowess.


Sexual selection evolved as one of the means of natural selection. A male, for instance, chooses a female to mate with, and, if need be, may tenaciously compete against other males to stack the odds in his favor. Charles Darwin’s long-standing theories on sexual selection are still relevant to this day. Darwin believed that sexual selection had a key role in how humans evolved and diverged into distinct human populations.[2] In view of that, sexual selection could have contributed as to how intelligence evolved.




Intelligent males, more attractive


budgerigars on mate selection
Female budgerigars (also called parakeets or budgies) apparently prefer smarter mates, according to a study. This finding seems to support Charles Darwin theory on mate selection.


Many studies on birds revolved around the notion that female birds favor male birds with vibrant feathers or stylish songs. A recent study claims that intelligence is preferred over such fancy features and skills.


In the first experiment conducted by Chen and colleagues[3], small budgerigars (Australian parrots) were observed inside their cages to test the hypothesis that intelligence might affect mate selection. To do that, they allowed each female budgerigars to choose among a pair of similarly-looking male budgerigars to interact with. The chosen males were called preferred whereas those that were not were referred to as the less-preferred. Next, they trained the less-preferred males into learning a skill that opens closed lids or boxes. They, then, allowed the female budgerigar to observe the less-preferred male demonstrate the skill. Consequently, almost all of the females changed their preference. They chose the less-preferred males over the initially preferred males.


To test if this preference was social rather than sexual, they conducted a second experiment with a similar experimental design but this time a female budgerigar was exposed to two females (instead of males). The results showed that none of the female budgerigars changed their preferences. [1, 3] Based on these experiments, the researchers concluded that the demonstration of cognitive skills altered mate preference but not necessarily social preference.


Video of the animal model, male budgerigar that learned a problem-solving skill that seemingly increased its attractiveness to females. [Credit: Hedwig Pöllöläinen].




Why did mate selection evolved? The answer could be associated with the species survival or longevity. Individuals must be able to stay in the mate selection pool, if not on top of it. In general, males deemed as superior or “preferred” will gain higher chances at mating, and thereby will have better opportunities at transmitting their genes as they dominate the access to fertile females. Females, on the other hand, gain an upper hand from the mate selection by being able to choose the seemingly finest among the rest. Females must choose. That is because they have a generally limited reproductive opportunity to give life to. Moreover, the energy that a female invests in producing an offspring is so great that it has to be worth it.



— written by Maria Victoria Gonzaga





1  Chen, J., Zou, Y., Sun, Y.-H., & ten Cate, C. (2019). Problem-solving males become more attractive to female budgerigars. Science363(6423), 166–167.


2  Jones, A. G., & Ratterman, N. L. (2009). Mate choice and sexual selection: What have we learned since Darwin? Proceedings of the National Academy of Sciences106(Supplement_1), 10001–10008.


3  GrrlScientist. (2019, January 11). Problem-Solving Budgies Make More Attractive Mates. Forbes. Retrieved from


Aerobic exercise modifies fine particle exposures to young adults

Aerobic exercise contributes to the prevention and treatment of various chronic diseases as well as helps improves endothelial function. It is also beneficial in adaptation of the cardio-pulmonary system and infection resistant. Moreover, aerobic exercise attributes to the release of vasoconstrictor substances and increased nitric oxide availability. However, exposure to fine particles in ambient condition linked to some adverse health effects. This includes oxidative stress, pulmonary systemic inflammation, increased blood coagulation and vascular imbalance. Aerobic exercise in polluted environments increased inhalation of air pollutants due to increased respiratory rate and reduction of nasal resistance. Also, long-term exercise aggravates air pollutant which causes associated respiratory impairment.


Air pollutant exposure during aerobic exercise

There were 20 healthy non-smoking male subjects on this study and aerobic exercise frequencies have been recorded. Wherein indices measured including fractional exhaled nitric oxide, blood pressures; cytokines exhaled breath condensate and pulse-wave analysis. However, the biomarkers of eosinophilic airway inflammation were positively associated with air pollution exposure. Also, the fractional exhaled nitric oxide concentrations were greater in high exercise frequency. Thus, explain that high strength exercise might be at higher risk of particle-mediated respiratory symptoms.


Aerobic exercise is associated with the exposure to air pollutant which caused respiratory inflammation and arterial stiffness. In terms of cardiovascular responses the increased in aortic augmentation pressure indicate higher pulse-wave velocity. Furthermore, aerobic exercise at moderate frequency had a greater protective effect against cardiopulmonary health risk than low or excessive exercise.


Therefore, long-term habitual aerobic exercise in severely polluted areas may strengthen the resistance of the cardiovascular system. But increase the risk of pollutant-related airway inflammation. In addition, surrogate biomarkers of atherosclerosis, arterial wall thickness have been decreased following the long-term aerobic exercise. And also low cardiopulmonary fitness is the key indicators for cardiovascular mortality and coronary heart disease.


Source: Prepared by Joan Tura from BMC Environmental Health

Volume 17:88 December 13, 2018