Evidence of Anti-Inflammatory Effect of Transcranial Direct Current Stimulation in a CFA-Induced Chronic Inflammatory Pain Model in Wistar Rats.

Autor: Silva SP; Laboratory of Cell Neuromodulation: Basic Research, Department of Morphology, Biology Institute, Universidade Federal de Pelotas, Pelotas, Brazil.; Postgraduate Program in Bioprospecting and Biochemistry, Universidade Federal de Pelotas, Pelotas, Brazil., Martins OG; Laboratory of Cell Neuromodulation: Basic Research, Department of Morphology, Biology Institute, Universidade Federal de Pelotas, Pelotas, Brazil., Medeiros LF; Postgraduate Program in Health and Human Development, Unilasalle, Canoas, Brazil, licimedeiros@gmail.com.; Laboratory of Pain Pharmacology and Neuromodulation: Preclinical Research, Hospital de Clínicas de Porto Alegre, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil, licimedeiros@gmail.com., Crespo PC; Laboratory of Cell Neuromodulation: Basic Research, Department of Morphology, Biology Institute, Universidade Federal de Pelotas, Pelotas, Brazil.; Postgraduate Program in Bioprospecting and Biochemistry, Universidade Federal de Pelotas, Pelotas, Brazil., do Couto CAT; Laboratory of Cell Neuromodulation: Basic Research, Department of Morphology, Biology Institute, Universidade Federal de Pelotas, Pelotas, Brazil.; Postgraduate Program in Bioprospecting and Biochemistry, Universidade Federal de Pelotas, Pelotas, Brazil., de Freitas JS; Laboratory of Pain Pharmacology and Neuromodulation: Preclinical Research, Hospital de Clínicas de Porto Alegre, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil., de Souza A; Postgraduate Program in Health and Human Development, Unilasalle, Canoas, Brazil., Morastico A; Laboratory of Cell Neuromodulation: Basic Research, Department of Morphology, Biology Institute, Universidade Federal de Pelotas, Pelotas, Brazil., Cruz LAX; Laboratory of Cell Neuromodulation: Basic Research, Department of Morphology, Biology Institute, Universidade Federal de Pelotas, Pelotas, Brazil., Sanches PRS; Biomedical Engineering of Hospital de Clínicas de Porto Alegre, Porto Alegre, Brazil., Caumo W; Postgraduate Program in Medicine, Medical Sciences, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil., Gamaro GD; Laboratory of Cell Neuromodulation: Basic Research, Department of Morphology, Biology Institute, Universidade Federal de Pelotas, Pelotas, Brazil.; Postgraduate Program in Bioprospecting and Biochemistry, Universidade Federal de Pelotas, Pelotas, Brazil., Torres ILDS; Laboratory of Pain Pharmacology and Neuromodulation: Preclinical Research, Hospital de Clínicas de Porto Alegre, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.; Postgraduate Program in Medicine, Medical Sciences, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil., de Souza ICC; Laboratory of Cell Neuromodulation: Basic Research, Department of Morphology, Biology Institute, Universidade Federal de Pelotas, Pelotas, Brazil.; Postgraduate Program in Bioprospecting and Biochemistry, Universidade Federal de Pelotas, Pelotas, Brazil.
Jazyk: angličtina
Zdroj: Neuroimmunomodulation [Neuroimmunomodulation] 2022; Vol. 29 (4), pp. 500-514. Date of Electronic Publication: 2022 Feb 02.
DOI: 10.1159/000520581
Abstrakt: Introduction: Given that chronic inflammatory pain is highly prevalent worldwide, it is important to study new techniques to treat or relieve this type of pain. The present study evaluated the effect of transcranial direct current stimulation (tDCS) in rats submitted to a chronic inflammatory model by nociceptive response, biomarker levels (brain-derived neurotrophic factor [BDNF] and interleukin [IL]-6 and IL-10), and by histological parameters.
Methods: Sixty-day-old male Wistar rats were used in this study and randomized by weight into 6 major groups: total control, control + sham-tDCS, control + active tDCS, total CFA, CFA + sham-tDCS, and CFA + active tDCS. After inflammatory pain was established, the animals were submitted to the treatment protocol for 8 consecutive days, according to the experimental group. The nociceptive tests (von Frey and hot plate) were assessed, and euthanasia by decapitation occurred at day 8 after the end of tDCS treatment, and the blood serum and central nervous structures were collected for BDNF and IL measurements. All experiments and procedures were approved by the Institutional Committee for Animal Care and Use (UFPel #4538).
Results: The tDCS treatment showed a complete reversal of the mechanical allodynia induced by the pain model 24 h and 8 days after the last tDCS session, and there was partial reversal of the thermal hyperalgesia at all time points. Serum BDNF levels were decreased in CFA + sham-tDCS and CFA + tDCS groups compared to the control + tDCS group. The control group submitted to tDCS exhibited an increase in serum IL-6 levels in relation to the other groups. In addition, there was a significant decrease in IL-10 striatum levels in control + tDCS, CFA, and CFA + sham-tDCS groups in relation to the control group, with a partial tDCS effect on the CFA pain model. Local histology demonstrated tDCS effects in decreasing lymphocytic infiltration and neovascularization and tissue regeneration in animals exposed to CFA.
Conclusion: tDCS was able to reverse the mechanical allodynia and decrease thermal hyperalgesia and local inflammation in a chronic inflammatory pain model, with a modest effect on striatum IL-10 levels. As such, we suggest that analgesic tDCS mechanisms may be related to tissue repair by modulating the local inflammatory process.
(© 2022 S. Karger AG, Basel.)
Databáze: MEDLINE