Brain Structural and Functional Alterations in Native Tibetans Living at High Altitude

Xinjuan Zhang; Weiwei Xie; Yanqiu Liu; Minglu Li; Jianzhong Lin; Wu Yin; Lihui Yang; Pengji Li; Ying Sun; Tianzhi Li; Haipeng Liu; Hailin Ma; Jiaxing Zhang

doi:10.1016/j.neuroscience.2023.01.019

Brain Structural and Functional Alterations in Native Tibetans Living at High Altitude

Neuroscience. 2023 Jun 1:520:134-143. doi: 10.1016/j.neuroscience.2023.01.019. Epub 2023 Jan 28.

Authors

Xinjuan Zhang¹, Weiwei Xie², Yanqiu Liu¹, Minglu Li³, Jianzhong Lin⁴, Wu Yin⁵, Lihui Yang⁶, Pengji Li², Ying Sun², Tianzhi Li², Haipeng Liu⁷, Hailin Ma⁸, Jiaxing Zhang⁹

Affiliations

¹ Institute of Brain Diseases and Cognition, School of Medicine, Xiamen University, Xiamen 361102, China; Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Xiamen University, Xiamen 361102, China.
² Plateau Brain Science Research Centre, Tibet University, Lhasa 850012, China.
³ Department of Clinical Medicine, School of Medicine, Xiamen University, Xiamen 361102, China.
⁴ Department of Radiology, Zhongshan Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen 361102, China.
⁵ Department of Radiology, Tibet Autonomous Region People's Hospital, Lhasa 850000, Tibet Autonomous Region, China.
⁶ Department of Endocrinology, Tibet Autonomous Region People's Hospital, Lhasa 850000, Tibet Autonomous Region, China.
⁷ Department of Radiology, Tibet Autonomous Region Women's and Children's Hospital, Lhasa 850000, Tibet Autonomous Region, China.
⁸ Plateau Brain Science Research Centre, Tibet University, Lhasa 850012, China. Electronic address: david_ma79@163.com.
⁹ Institute of Brain Diseases and Cognition, School of Medicine, Xiamen University, Xiamen 361102, China; Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Xiamen University, Xiamen 361102, China. Electronic address: zhangjiaxing@xmu.edu.cn.

PMID: 36716913
DOI: 10.1016/j.neuroscience.2023.01.019

Abstract

Tibetans have adapted to high altitude environments. However, the genetic effects in their brains have not been identified. Twenty-five native Tibetans living in Lhasa (3650 m) were recruited for comparison with 20 Han immigrants who originated from lowlands and had been living in Lhasa for two years. The physiological characteristics, brain structure and neuronal spontaneous activity were investigated. Compared with Han immigrants, Tibetans showed higher peripheral oxygen saturation (SpO₂), and lower heart rate, red blood cell counts, hematocrit, and hemoglobin. Tibetans showed increased gray matter volume in the visual cortex, hippocampus, and rectus; increased the amplitudes of low-frequency fluctuations (ALFF) values in the left putamen and left fusiform gyrus; and decreased voxel-mirrored homotopic connectivity (VMHC) values in the precentral gyrus. Moreover, Tibetans have decreased functional connectivity (FC) between the left precentral gyrus and the frontal gyrusand right precuneus. In Tibetans and Han immigrants, hemoglobin and hematocrit were negatively correlated with total gray matter volume in males, SpO₂ was also positively correlated with ALFF in the left fusiform gyrus, while hemoglobin, and hematocrit were positively correlated with VMHC in the precentral gyrus and FC in the precentral gyrus with other brain regions, SpO₂ was also found to be negatively correlated with VMHC in the precentral gyrus, and hemoglobin and hematocrit were negatively correlated with ALFF in the left putamen and left fusiform gyrus. In summary, genetic mutations may result in modulation of some brain regions, which was further confirmed by the identification of correlations with hemoglobin and hematocrit in these regions.

Keywords: Tibetans; brain structure; spontaneous brain activity.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Altitude*
Brain / diagnostic imaging
Hemoglobins
Humans
Magnetic Resonance Imaging*
Male
Tibet

Substances

Hemoglobins