In the primary few days after a traumatic brain injury (TBI), food is commonly an afterthought as clinicians deal with minimizing the damage to the brain. Nevertheless, a recent study suggests that getting enough calories may also help boost the brain’s healing process, making nutrition a very important consideration for improving TBI care. Researchers will present their work this week on the American Physiology Summit, the flagship annual meeting of the American Physiological Society (APS), in Long Beach, California.

This evidence highlights the importance of ensuring proper nutrition for TBI patients during recovery. Specifically, formulations containing fuels which are preferred by the brain, corresponding to lactate, needs to be prioritized through the acute and chronic phases of recovery from TBI.”

Casey C. Curl, Doctoral Candidate, Exercise Physiology Laboratory, University of California, Berkeley

When an individual involves the hospital with a traumatic brain injury, many patients go for several days without eating and even receiving nutrition through a tube or intravenous line. Even then, the tools clinicians use to calculate a patient’s dietary needs are usually not designed for the unique circumstances of a brain injury, and up to date studies suggest that almost all TBI patients get far fewer calories than they need.

Key to the research is a recent biomarker the team developed to evaluate dietary status. While it is feasible to measure the quantity of calories an individual consumes, measuring whether the quantity of calories provided to the patient to satisfy their energy needs is more complex. To fill this gap, the researchers created a approach to measure the quantity of glucose produced internally because the body processes energy inputs. This metric, called fractional gluconeogenesis, ranges from zero (fully fed) to 100% (drastically underfed).

For the study, researchers tracked how dietary status affects fractional gluconeogenesis and protein synthesis in a rat model of TBI. They used deuterium oxide, also often called heavy water, as a tracer to evaluate fractional gluconeogenesis and protein synthesis in numerous parts of the brain and body. By comparing these dynamics in rats with different levels of caloric intake, they were in a position to gain insights into how nutrition affects brain healing processes.

“Our study found that after TBI, the brain responds abnormally by increasing protein synthesis in the upper brain region while decreasing it within the lower regions,” said Curl.

Previous studies have shown that being underfed results in reduced protein synthesis in skeletal muscle and liver cells. The brand new findings suggest an analogous thing happens within the brain. “Understanding this decrease in protein turnover through the brain healing process is crucial because a caloric deficit may affect the patient’s ability to heal from their injury,” said Curl.

The findings suggest that providing adequate nutrition within the aftermath of a traumatic brain injury may also help the brain manufacture the proteins it needs for the healing process, without having to prioritize certain brain regions over others.

Along with feeding patients sooner as a part of routine practice, Curl noted that clinicians could use fractional gluconeogenesis as a practical metric to evaluate whether patients are getting enough calories during TBI treatment and recovery.

This research was funded by a grant from the PAC-12 conference.

Source:

American Physiological Society (APS)