open access

Vol 79, No 4 (2020)
Original article
Published online: 2019-12-20
Submitted: 2019-08-26
Accepted: 2019-12-02
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Increased number of activated microglia in rat spinal cord during early stage of diabetic induction

P. Lanlua, A. Prommahom, S. Sricharoenvej
DOI: 10.5603/FM.a2019.0136
·
Pubmed: 31886881
·
Folia Morphol 2020;79(4):662-671.

open access

Vol 79, No 4 (2020)
ORIGINAL ARTICLES
Published online: 2019-12-20
Submitted: 2019-08-26
Accepted: 2019-12-02

Abstract

Background: Diabetic neuropathy is a common chronic complication in diabetes mellitus. Such neuropathy associates with chronic inflammation and immune system activation. Microglia, a type of neuroglia, are involved in the immune system and are found in grey and white matter of the central nervous system, such as the brain and spinal cord. The spinal cord connects the peripheral nervous system and the higher brain centre. Hyperglycaemia during diabetes mellitus has been found to activate and increase number of microglia in the dorsal grey horn or column of the lumbar segments in spinal cord, which release several cytokines in the development of hypersensitivity in diabetic neuropathic pain.

Materials and methods: Therefore, in this study, anatomical alterations of rat spinal microglia in all areas (dorsal, intermediate and ventral columns of grey matter and dorsal, lateral and ventral funiculi of white matter) in cervical enlargement, thoracic level and lumbosacral enlargement were observed in early stage of diabetic conditions by using light and transmission electron microscopies.

Results: The numbers of microglia in all parts of grey and white matter of all spinal levels significantly increased in the diabetic group. The structures and ultrastructures of microglia in grey and white matter at cervical enlargement, thoracic level and lumbosacral enlargement similarly changed in diabetes. In diabetic rats, microglia became hypertrophied with a pale nucleus. Moreover, short fragments of rough endoplasmic reticulum, elevated numbers of lysosomes and numerous actin filaments in the cytoplasm were examined. Microglial phagocytosis of myelin and axonal debris were also observed. In this investigation, the morphology of spinal microglia during short-term diabetes became activated during hyperglycaemia.

Conclusions: It is suggested that these changes may be involved in the development of diabetic neuropathic pain in the spinal cord.

Abstract

Background: Diabetic neuropathy is a common chronic complication in diabetes mellitus. Such neuropathy associates with chronic inflammation and immune system activation. Microglia, a type of neuroglia, are involved in the immune system and are found in grey and white matter of the central nervous system, such as the brain and spinal cord. The spinal cord connects the peripheral nervous system and the higher brain centre. Hyperglycaemia during diabetes mellitus has been found to activate and increase number of microglia in the dorsal grey horn or column of the lumbar segments in spinal cord, which release several cytokines in the development of hypersensitivity in diabetic neuropathic pain.

Materials and methods: Therefore, in this study, anatomical alterations of rat spinal microglia in all areas (dorsal, intermediate and ventral columns of grey matter and dorsal, lateral and ventral funiculi of white matter) in cervical enlargement, thoracic level and lumbosacral enlargement were observed in early stage of diabetic conditions by using light and transmission electron microscopies.

Results: The numbers of microglia in all parts of grey and white matter of all spinal levels significantly increased in the diabetic group. The structures and ultrastructures of microglia in grey and white matter at cervical enlargement, thoracic level and lumbosacral enlargement similarly changed in diabetes. In diabetic rats, microglia became hypertrophied with a pale nucleus. Moreover, short fragments of rough endoplasmic reticulum, elevated numbers of lysosomes and numerous actin filaments in the cytoplasm were examined. Microglial phagocytosis of myelin and axonal debris were also observed. In this investigation, the morphology of spinal microglia during short-term diabetes became activated during hyperglycaemia.

Conclusions: It is suggested that these changes may be involved in the development of diabetic neuropathic pain in the spinal cord.

Get Citation

Keywords

diabetes mellitus, microglia, spinal cord, rat

About this article
Title

Increased number of activated microglia in rat spinal cord during early stage of diabetic induction

Journal

Folia Morphologica

Issue

Vol 79, No 4 (2020)

Article type

Original article

Pages

662-671

Published online

2019-12-20

DOI

10.5603/FM.a2019.0136

Pubmed

31886881

Bibliographic record

Folia Morphol 2020;79(4):662-671.

Keywords

diabetes mellitus
microglia
spinal cord
rat

Authors

P. Lanlua
A. Prommahom
S. Sricharoenvej

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