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Tag: human brain

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]

Implications

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

References:

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

Hubs in the Human Fetal Brain Network

Human brain contains highly connected regions called “hubs” that are very important for efficient neuronal signaling and communication. In mature individual hubs are constantly found in precuneus, cingulate gyrus, frontal cortex and interior parietal regions. Evidences reveal that because of this highly functional human brain, the hubs support information integration for complex cognitive function. In line with this, abnormal hubs have been implicated to various neurological brain disorders. So the central role of hubs in human brain at the beginning of human life is valuable. Since, it offers insight about the origins of psychiatric and developmental disorders of the human brain at the later life.

 

Location of hubs in fetal human brain

Hubs were located in cerebellum, inferior temporal gyrus, angular gyrus, precentral gyrus, primary visual cortex and medial temporal lobe. Several hubs found in sensory and motor brain areas. Overall, more hubs were observed in the left rather than the right hemisphere suggesting asymmetry of hub association. Also hubs found in areas close to adult facial fusiform and homologous areas. Taken together, results suggest that hubs emerge before birth and serves as the important building block in human brain development.

 

This is the first research study about the functional hubs in human brain prior to birth. It reveals that within the organization of fetal brain there are hubs that are already important for neural efficiency. Particularly in both primary and association brain regions shows centrality in network before birth. The fetal brain network is not wired exclusively for perception but instead, prepare the brain for higher cognitive functioning in later life.

 

Hence, the network organization of fetal human brain contains hubs that are central to the architectural neural circuitry. Hubs were identified in motor and visual areas as well as in association cortices of the fetal brain. Interestingly, many hubs were localized in cerebellar region supporting the idea that hubs emerge in areas early to myelinate. It is hypothesized that, because of high centrality in network, hub regions generates neural activity that stimulates myelin. Additionally, hubs are significant for global efficiency of the fetal human brain network for higher cognitive functioning and serve as biomarkers for neurodevelopmental disorders.

 

Source: Prepared by Joan Tura from Developmental Cognitive Neuroscience

Volume 30, April 2018, Pages 108-115