Welcome to The Visible Embryo

Home- - -History-- -Bibliography- -Pregnancy Timeline- --Prescription Drugs in Pregnancy- -- Pregnancy Calculator- --Female Reproductive System- News Alerts -Contact

Welcome to The Visible Embryo, a comprehensive educational resource on human development from conception to birth.

The Visible Embryo provides visual references for changes in fetal development throughout pregnancy and can be navigated via fetal development or maternal changes.

The National Institutes of Child Health and Human Development awarded Phase I and Phase II Small Business Innovative Research Grants to develop The Visible Embryo. Initally designed to evaluate the internet as a teaching tool for first year medical students, The Visible Embryo is linked to over 600 educational institutions and is viewed by more than ' million visitors each month.


WHO International Clinical Trials Registry Platform
The World Health Organization (WHO) has created a new Web site to help researchers, doctors and patients obtain reliable information on high-quality clinical trials. Now you can go to one website and search all registers to identify clinical trial research underway around the world!



Home

History

Bibliography

Pregnancy Timeline

Prescription Drug Effects on Pregnancy

Pregnancy Calculator

Female Reproductive System

Contact The Visible Embryo

News Archive
Disclaimer: The Visible Embryo web site is provided for your general information only. The information contained on this site should not be treated as a substitute for medical, legal or other professional advice. Neither is The Visible Embryo responsible or liable for the contents of any websites of third parties which are listed on this site.
Content protected under a Creative Commons License.

No dirivative works may be made or used for commercial purposes.

Return To Top Of Page
Pregnancy Timeline by SemestersFemale Reproductive SystemFertilizationThe Appearance of SomitesFirst TrimesterSecond TrimesterThird TrimesterFetal liver is producing blood cellsHead may position into pelvisBrain convolutions beginFull TermWhite fat begins to be madeWhite fat begins to be madeHead may position into pelvisImmune system beginningImmune system beginningPeriod of rapid brain growthBrain convolutions beginLungs begin to produce surfactantSensory brain waves begin to activateSensory brain waves begin to activateInner Ear Bones HardenBone marrow starts making blood cellsBone marrow starts making blood cellsBrown fat surrounds lymphatic systemFetal sexual organs visibleFinger and toe prints appearFinger and toe prints appearHeartbeat can be detectedHeartbeat can be detectedBasic Brain Structure in PlaceThe Appearance of SomitesFirst Detectable Brain WavesA Four Chambered HeartBeginning Cerebral HemispheresEnd of Embryonic PeriodEnd of Embryonic PeriodFirst Thin Layer of Skin AppearsThird TrimesterDevelopmental Timeline
Click weeks 0 - 40 and follow fetal growth
Search artcles published since 2007

November 6, 2012--------News Archive Return to: News Alerts


In Alzheimer's and traumatic brain injury, neurons (red)
are killed off by the protein appoptosin


Below, steps in the cycle of apoptosis (cell death).













WHO Child Growth Charts

       

Hunting Neuron Killers in Alzheimer’s and TBI

Sanford-Burnham researchers discovered that the protein appoptosin prompts neurons to commit suicide in several neurological conditions—giving them a new therapeutic target for Alzheimer’s disease and traumatic brain injury

by Heather Buschman

Dying neurons lead to cognitive impairment and memory loss in patients with neurodegenerative disorders–conditions like Alzheimer’s disease and traumatic brain injury. To better diagnose and treat these neurological conditions, scientists first need to better understand the underlying causes of neuronal death.

Enter Huaxi Xu, Ph.D., professor in Sanford-Burnham’s Del E. Webb Neuroscience, Aging, and Stem Cell Research Center. He and his team, for the past several years, study the protein appoptosin and its role in neurodegenerative disorders. Appoptosin levels skyrocket in the brain with conditions like Alzheimer’s and stroke, and especially following traumatic brain injury.


Appoptosin is known for its role in helping
the body make heme, the molecule that carries
iron in our blood (think “hemoglobin,”
which makes blood red). But what does heme
have to do with dying brain cells?

Xu and his group explain in a paper published
recently in the Journal of Neuroscience,
excess heme leads to the overproduction
of reactive oxygen species, which include
cell-damaging free radicals and peroxides,
and triggers apoptosis, the carefully regulated
process of cellular suicide.

This means that more appoptosin
and more heme cause neurons to die.


Not only did Xu and his team unravel this whole appoptosin-heme-neurodegeneration mechanism, but when they inhibited appoptosin in laboratory cell cultures, they noticed that the cells didn’t die. This finding suggests that appoptosin might make an interesting new therapeutic target for neurodegenerative disorders.

What’s next? Xu and colleagues are now probing appoptosin’s function in mouse models. They’re also looking for new therapies that target the protein.

“Since the upregulation of appoptosin is important for cell death in diseases such as Alzheimer’s, we’re now searching for small molecules that modulate appoptosin expression or activity. We’ll then determine whether these compounds may be potential drugs for Alzheimer’s or other neurodegenerative diseases,” Xu explains.

Putting a stop to runaway appoptosin won’t be easy, though. That’s because we still need the heme-building protein to operate at normal levels for our blood to carry iron. In a previous study, researchers found that a mutation in the gene that encodes appoptosin causes anemia. “Too much of anything is bad, but so is too little,” Xu says.

New therapies that target neurodegenerative disorders and traumatic brain injury are sorely needed.


According to the CDC, approximately 1.7 million
people sustain a traumatic brain injury each year.

It’s an acute injury, but one that can also lead
to long-term problems, causing epilepsy and
increasing a person’s risk for Alzheimer’s
and Parkinson’s diseases.

Not only has traumatic brain injury become
a worrisome problem in youth and professional
sports in recent years, the Department of Defense
calls traumatic brain injury “one of the signature
injuries of troops wounded in Afghanistan and Iraq.”


This study was funded by the U.S. National Institutes of Health (National Institute on Aging grants R01AG038710, R01AG021173, R01AG030197, R03AG034366, R01AG031893, AG5131, AG18440, R21AG038968; National Institute of Neurological Disorders and Stroke grants R01NS046673, R01NS054880) and the Alzheimer’s Association.

Original paper:
Zhang H, Zhang YW, Chen Y, Huang X, Zhou F, Wang W, Xian B, Zhang X, Masliah E, Chen Q, Han JD, Bu G, Reed JC, Liao FF, Chen YG, & Xu H (2012). Appoptosin is a Novel Pro-Apoptotic Protein and Mediates Cell Death in Neurodegeneration. The Journal of neuroscience : the official journal of the Society for Neuroscience, 32 (44), 15565-15576 PMID: 23115192

Original article: http://beaker.sanfordburnham.org/2012/11/hunting-neuron-killers-alzheimers-tbi/