Scientists have shown that ukol sa kapaligiran stress can affect normal development of kinakabahan system in worms who are approaching puberty
Scientists have been trying to understand how our genes (our genetic makeup) and different ukol sa kapaligiran factors shape our nervous system sa panahon ng maagang pag-unlad kapag tayo ay lumalaki. Ang kaalamang ito ay maaaring higit pang maunawaan ang iba't ibang neurological disorder na pangunahing sanhi kapag ang mga normal na neural circuit sa ating nervous system ay nasira. Sa isang pag-aaral na inilathala sa Kalikasan, siyentipiko from Columbia University have studied the nervous system of small transparent worms (C. elegans) to elucidate understanding of how it shapes up. They show that stress caused by environmental factors can have a permanent intense effect on connections taking place in the nervous system which is still developing. In their experiment they made male worms undergo starvation just before the worms were to undergo sexual maturation with an aim to stunt their puberty. Exposure to external stress, specifically starvation, even a few days before sexual maturation affected wiring patterns of critical neuronal circuits in worm’s kinakabahan system thus preventing normal changes to take place. The rewiring program of their nervous system was basically interrupted. Once these ‘pagkabalisa’ males underwent puberty and became adult, immature circuits still remained in their nervous system causing them to continue to act immature. Their Immaturity was judged by observing that stressed adult male worms showed high sensitivity to a toxic chemical called SDS compared to normal adult males. The stressed worms also spent limited time with other hermaphrodite worms and had difficulties in mating.
Siyentipiko made this crucial discovery when some worms were accidently left unattended for some weeks and not given food. This led to a pause in worms’ normal development and they entered a state called ‘dauer state’. This state is like a temporary halt in normal growth of an organism. In case of worms, when immature worms sensed any type of stress, a temporary pause happens in their normal growth for months and later once the stress is gone their growth resumes. So, after stress of starvation passed, worms returned to their normal environment and they went on to mature into adults. Upon examining the nervous system of now adult worms, it was seen that some immature connections in male worm’s tails were retained which would ideally have been eliminated (or pruned) during sexual maturation. Researchers investigated further to state that ‘dauer state’ was caused exclusively by stress of starvation and not by any other form of stress. The stress led to remapping of their wire diagrams. The opposite effects of two neurotransmitters – serotonin and octopamine – control pruning of circuits. The stressed worms had high amount of octopamine which then blocked production of serotonin. If serotonin was given to immature males during stress, then normal pruning took place and adults start exhibiting mature reaction to SDS. In comparison when octopamine was given to immature males, this prevented the circuit pruning. Study suggests that stress can have a likely effect on changes in nervous system when maagang development is taking place. The neurotransmitter serotonin is associated with mental condition of depression in humans.
Totoo kaya ang posibilidad na ito para sa mga tao noon? Hindi ito diretso sa mga tao dahil mayroon tayong mas malaki at mas kumplikadong sistema ng nerbiyos kumpara sa mga hayop. Gayunpaman, ang mga bulate ay isang simple ngunit mahusay na modelo ng mga organismo upang pag-aralan at pag-aralan ang mga sistema ng nerbiyos. Ang mga nangungunang mananaliksik ng pag-aaral na ito ay nagpasimula ng isang proyekto na tinatawag na ceNGEN kung saan sila ay magmamapa ng genetic makeup at aktibidad ng bawat neuron sa C. elegans worm's nervous system na makakatulong upang maunawaan ang mga paggawa ng nervous system nang mas detalyado at ang posibleng pakikipagtulungan sa pagitan ng isang tao. genetic makeup at mga karanasan ng isang tao.
***
{Maaari mong basahin ang orihinal na papel ng pananaliksik sa pamamagitan ng pag-click sa link ng DOI na ibinigay sa ibaba sa listahan ng (mga) binanggit na pinagmulan}
Pinagmulan (s)
Bayer EA at Hobert O. 2018. Ang nakaraang karanasan ay humuhubog sa sexually dimorphic neuronal wiring sa pamamagitan ng monoaminergic signaling. Kalikasan. https://doi.org/10.1038/s41586-018-0452-0
***
