Rong Zhang, Ph.D., releases findings from multiple clinical trials focused on exercise, aging, and Alzheimer's

By Julie Kirchem, Department of Neurology and Neurotherapeutics

Rong Zhang, PhD
Rong Zhang, Ph.D.

DALLAS - Sept. 25, 2012 - Rong Zhang, Ph.D., and fellows Benjamin Tseng, PhD, and Jie Liu, M.D., Ph.D., presented their research findings that link exercise and vascular aging with brain structure and function at this year's Alzheimer's Association International Conference. The conference was held in July in Vancouver, Canada.

Dr. Zhang is associate professor of internal medicine, and neurology and neurotherapeutics at UT Southwestern Medical Center, and director of the Cerebrovascular Lab at the Institute for Exercise and Environmental Medicine at Presbyterian Hospital in Dallas.

Staff of Cerebrovascular Lab - Institute for Exercise and Environmental Medicine
Staff of Cerebrovascular Lab - Institute for Exercise and Environmental Medicine

Dr. Zhang and his colleagues conducted National Institute on Aging (NIA)-supported clinical trials of exercise training in patients with mild cognitive impairment, a preclinical stage of Alzheimer’s disease (AD).

In one study, researchers measured cardiovascular response during exercise.

“What we found is that exercise testing is feasible and can be performed safely in these patients,” Dr. Zhang said. “This is valuable information for clinicians who might consider exercise as an intervention to slow brain aging or Alzheimer's disease.”

The studies also found that higher arterial stiffness, a hallmark of vascular aging, is related to more severe brain damage in patients with mild cognitive impairment.

“In addition, we found that brain blood flow is reduced in these patients and is likely related to impairment of cerebral autoregulation, a protective mechanism of brain blood vessels to maintain proper brain perfusion,” Dr. Zhang said.

Collectively, these findings suggest that cerebral vascular abnormalities may precede and contribute to the clinical onset of Alzheimer’s disease.

Summary of the studies presented at the AAIC:

Benjamin Tseng, Ph.D.
Title: Cardiovascular Response during Maximal Treadmill Exercise in
Patients with Mild Cognitive Impairment
Summary: This study demonstrated the feasibility and safety of conducting maximal exercise testing and cardiovascular responses during exercise testing in patients with amnestic mild cognitive impairment (MCI), a preclinical  stage of AD .

Benjamin Tseng, Ph.D.
Title: Elevated Arterial Stiffness and Deep-Brain White Matter
Hyperintensities in Patients with Mild Cognitive Impairment
Summary: This study observed that the severity of white matter diseases in patients with amnestic mild cognitive impairment (MCI) is correlated with arterial stiffness, a hallmark of vascular aging.

Jie Liu, M.D., Ph.D.
Title: Compromised Cerebral Autoregulation in Patients with Mild
Cognitive Impairment
Summary: This study showed that cerebral autoregulation, a protective mechanism of brain vasculature to maintain brain blood flow, is impaired in patients with amnestic mild cognitive impairment (MCI) when compared to the age matched normal older adults.

Yong-Sheng Zhu, M.D., Ph.D.
Title: Increase in Cerebrovascular Resistance and reduction in Cerebral
Blood Flow in Patients with Mild Cognitive Impairment
Summary: This study showed that brain blood flow is reduced associated with increases in cerebrovascular resistance in patients with amnesic mild cognitive impairment (MCI) indicating that changes in cerebral hemodynamics may precede and contribute to the clinical onset of AD.

Rong Zhang, Ph.D.
Title: Disruption of limbic white matter tracts in patients with mild cognitive impairment.
Summary: This study showed that abnormality of brain limbic white matter tracts related to memory function occurs in patients with amnesic mild cognitive impairment (MCI) and that that these novel  MRI diffusion tensor imaging measurements  may be  sensitive biomarkers for early detection of AD.