Cellular distribution of glucose and monocarboxylate transporters in human brain white matter and MS lesions
Neurobiology and immunology:
Mitochondrial dysfunction and disturbed energy metabolism are evident in MS and are thought to play an important role in disease progression. To ensure efficient energy supply to the high demanding brain, nutrients are transported into brain cells via specific glucose (GLUT) and monocarboxylate transporters (MCT).
The research aimed to study the expression of GLUTs and MCTs in MS lesions. White matter brain samples were obtained from 13 MS patients and 11 non-neurological controls. White matter samples were analysed through immunohistochemistry and immunofluorescence. Capillaries, astrocytes and microglia were isolated to obtain RNA.
In active demyelinating MS lesions, GLUT1, -3, and -4 expression was markedly increased. Analysis of chronic active MS lesions revealed marked GLUT staining in the active rim and reduced GLUT proteins in the inactive centre of the lesions. Moreover, in active MS lesions the staining intensity of MCT1, -2, and -4 was evidently increased.
MCT1 expression was also increased in astrocytes in active MS lesions. In chronic active MS lesions, MCT1 expression was markedly enhanced in astrocytes, whereas MCT1 staining was decreased in the perilesional region.
MCT2 was predominantly expressed in axons in the inactive centre of chronic active lesions and MCT4 immunoreactivity was restricted to astrocytes. PGC-1a was weakly expressed in astrocytes in the NAWM and increased astrocytic immunoreactivity was found within and around active lesions.
Authors: Nijland PG, Michailidou I.
Source: Glia. 2014 Apr 1. doi: 10.1002/glia.22667. [Epub ahead of print]
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