» Articles » PMID: 33114176

Aging-Related Phenotypic Conversion of Medullary Microglia Enhances Intraoral Incisional Pain Sensitivity

Overview
Journal Int J Mol Sci
Publisher MDPI
Date 2020 Oct 29
PMID 33114176
Citations 5
Authors
Affiliations
Soon will be listed here.
Abstract

Activated microglia involved in the development of orofacial pain hypersensitivity have two major polarization states. The aim of this study was to assess the involvement of the aging-related phenotypic conversion of medullary microglia in the enhancement of intraoral pain sensitivity using senescence-accelerated mice (SAM)-prone/8 (SAMP8) and SAM-resistant/1 (SAMR1) mice. Mechanical head-withdrawal threshold (MHWT) was measured for 21 days post palatal mucosal incision. The number of CD11c-immunoreactive (IR) cells [affective microglia (M1)] and CD163-IR cells [protective microglia (M2)], and tumor-necrosis-factor-α (TNF-α)-IR M1 and interleukin (IL)-10-IR M2 were analyzed via immunohistochemistry on days 3 and 11 following incision. The decrease in MHWT observed following incision was enhanced in SAMP8 mice. M1 levels and the number of TNF-α-IR M1 were increased on day 3 in SAMP8 mice compared with those in SAMR1 mice. On day 11, M1 and M2 activation was observed in both groups, whereas IL-10-IR M2 levels were attenuated in SAMP8 mice, and the number of TNF-α-IR M1 cells increased, compared to those in SAMR1 mice. These results suggest that the mechanical allodynia observed following intraoral injury is potentiated and sustained in SAMP8 mice due to enhancement of TNF-α signaling, M1 activation, and an attenuation of M2 activation accompanying IL-10 release.

Citing Articles

Exploring the Connectivity of Neurodegenerative Diseases: Microglia as the Center.

Wang Y, Cui L, Zhao H, He H, Chen L, Song X J Inflamm Res. 2023; 16:6107-6121.

PMID: 38107384 PMC: 10725686. DOI: 10.2147/JIR.S440377.


Age-related Changes in Trigeminal Ganglion Macrophages Enhance Orofacial Ectopic Pain After Inferior Alveolar Nerve Injury.

Fujiwara S, Urata K, Oto T, Hayashi Y, Hitomi S, Iwata K In Vivo. 2023; 37(1):132-142.

PMID: 36593019 PMC: 9843755. DOI: 10.21873/invivo.13062.


A simplified procedure for isolation of primary murine microglia.

Scott N, Witt K, Schober J Biotechniques. 2022; 73(6):273-279.

PMID: 36398847 PMC: 9761776. DOI: 10.2144/btn-2022-0054.


Unveiling Targets for Treating Postoperative Pain: The Role of the TNF-α/p38 MAPK/NF-κB/Nav1.8 and Nav1.9 Pathways in the Mouse Model of Incisional Pain.

de Lima F, Lauria P, do Espirito-Santo R, Evangelista A, Nogueira T, Araldi D Int J Mol Sci. 2022; 23(19).

PMID: 36232927 PMC: 9570460. DOI: 10.3390/ijms231911630.


Chronic Pain in the Elderly: Mechanisms and Distinctive Features.

Tinnirello A, Mazzoleni S, Santi C Biomolecules. 2021; 11(8).

PMID: 34439922 PMC: 8391112. DOI: 10.3390/biom11081256.

References
1.
Orihuela R, McPherson C, Harry G . Microglial M1/M2 polarization and metabolic states. Br J Pharmacol. 2015; 173(4):649-65. PMC: 4742299. DOI: 10.1111/bph.13139. View

2.
Obata H, Eisenach J, Hussain H, Bynum T, Vincler M . Spinal glial activation contributes to postoperative mechanical hypersensitivity in the rat. J Pain. 2006; 7(11):816-22. DOI: 10.1016/j.jpain.2006.04.004. View

3.
Urata K, Shinoda M, Honda K, Lee J, Maruno M, Ito R . Involvement of TRPV1 and TRPA1 in incisional intraoral and extraoral pain. J Dent Res. 2015; 94(3):446-54. PMC: 4814018. DOI: 10.1177/0022034514565645. View

4.
Urata K, Shinoda M, Ikutame D, Iinuma T, Iwata K . Involvement of transient receptor potential vanilloid 2 in intra-oral incisional pain. Oral Dis. 2018; 24(6):1093-1100. DOI: 10.1111/odi.12853. View

5.
Ma Y, Wang J, Wang Y, Yang G . The biphasic function of microglia in ischemic stroke. Prog Neurobiol. 2016; 157:247-272. DOI: 10.1016/j.pneurobio.2016.01.005. View