Cicardian system suffers and protects from prenatal cocaine exposure

Jul 11, 2007

Researchers from Boston University School of Medicine (BUSM) have shown that prenatal cocaine exposure in zebrafish (which share the majority of the same genes with humans) can alter neuronal development and acutely dysregulate the expression of circadian genes and those affecting melatonin signaling, growth and neurotransmission.

The circadian factors, including the principal circadian hormone melatonin, can attenuate the prenatal effects of cocaine. These findings appear in the July 11th issue of the journal PLoS ONE.

Tens of thousands of babies that have been exposed to cocaine in utero are born in the United States each year.

Multiple human studies suggest there are significant changes in brain development and subsequent brain function of children of drug-addicted parents. However, the extent of the damage and whether it is in part due to confounding environmental, genetic or physiological factors remains controversial.

Using a specifically developed zebrafish, the researchers, Drs. Eva Shang and Irina Zhdanova, found that prenatal exposure to cocaine, in concentrations comparable to those experienced by human embryos, altered the neuronal development in zebrafish and acutely changed embryonic expression of genes regulating growth, neurotransmission and circadian system.

“Moreover, we found that the effects of the cocaine exposure were dependent on time of exposure, being more robust in the day, and were blocked or attenuated by the principal circadian hormone, melatonin, produced exclusively at night,” said lead author Irina Zhdanova, MD, PhD, an associate professor in the department of anatomy and neurobiology at BUSM. “Thus the circadian system might be at the core of the developmental effects of cocaine and their inter-individual variability,” she added.

According to Zhdanova, circadian factors, including melatonin, could provide new therapeutic strategies to counteract the developmental effects of prenatal cocaine exposure.

Source: Boston University

Explore further: Vietnam's taste for cat leaves pets in peril

add to favorites email to friend print save as pdf

Related Stories

Social Security spent $300M on 'IT boondoggle'

10 hours ago

(AP)—Six years ago the Social Security Administration embarked on an aggressive plan to replace outdated computer systems overwhelmed by a growing flood of disability claims.

Cheaper wireless plans cut into AT&T 2Q profit

10 hours ago

(AP)—AT&T posted lower net income for the latest quarter due to cheaper cellphone plans it introduced as a response to aggressive pricing from smaller competitor T-Mobile US.

Awarded a Pell Grant? Better double-check

10 hours ago

(AP)—Potentially tens of thousands of students awarded a Pell Grant or other need-based federal aid for the coming school year could find it taken away because of a mistake in filling out the form.

Recommended for you

Vietnam's taste for cat leaves pets in peril

just added

The enduring popularity of "little tiger" as a snack to accompany a beer in Vietnam means that cat owners live in constant fear of animal snatchers, despite an official ban.

New species of mayfly discovered in India

1 hour ago

Scientists have discovered a new species of mayfly in the southern Western Ghats, a mountain range along the west coast of India. In fact, this is the first time that any mayfly belonging to the genus Labiobaetis has be ...

Giant anteaters kill two hunters in Brazil

Jul 26, 2014

Giant anteaters in Brazil have killed two hunters in separate incidents, raising concerns about the animals' loss of habitat and the growing risk of dangerous encounters with people, researchers said.

Rising temperatures can be hard on dogs

Jul 25, 2014

The "dog days of summer" are here, but don't let the phrase fool you. This hot time of year can be dangerous for your pup, says a Kansas State University veterinarian.

User comments : 0