Breakthrough research by scientists at the Victor Chang Cardiac Research Institute in Australia could lead to identifying the cause for multiple types of birth defects triggered by environmental stresses. Scientists at the institute have shown thatcellular stress could be the key to understanding why many babies are born with defects of the heart, vertebrae and kidney, among others.
Affecting 1 in 100 babies, childhood heart disease is the most common form of birth defect in the world. But despite its prevalence, surprisingly the genetic and environmental causes are very poorly understood.
The research analyzed the effects of short term oxygen deficiency on heart development in an embryo. Oxygen deficiency in an embryo can be caused by many things, for example prescription medications, high blood pressure, high altitude, a tangled umbilical cord, as well as carbon monoxide.
Using a mouse model, the scientists reduced oxygen levels inside a chamber from the normal level of 21 percent to as low as 5.5 percent, for eight hours. They found for the first time that reduced oxygen levels damaged the developing heart. The types of heart defects were the same as those most commonly found in humans. Crucially the scientists worked out exactly how the low oxygen was damaging the developing heart.
The researchers said their study showed that reduced oxygen triggered a stress response in the embryonic cells. The cells then try to relieve the stress by stopping protein production needed to make the heart at a critical time leading to the heart not developing properly.
Importantly, oxygen deficiency is not the only trigger of this cellular stress. There are multiple factors which can set it off, such as a viral infections, increased temperature, high blood glucose, poor nutrition, and pollution.
Cellular stress response could be the key to a variety of birth defects, including those of the vertebrae, kidney and others.