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Wolnei Caumo,1–3 Maria Paz Hidalgo,4,5 Andressa Souza,6 Iraci LS Torres,1,7 Luciana C Antunes8 1School of Medicine, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil; 2Pain and Palliative Care Service at Hospital de Clínicas de Porto Alegre (HCPA), Laboratory of Pain and Neuromodulation at UFRGS, Porto Alegre, Brazil; 3Pain and Anesthesia in Surgery Department, School of Medicine, UFRGS, Porto Alegre, Brazil; 4Psychiatry Department, School of Medicine, UFRGS, Porto Alegre, Brazil; 5Laboratorio de Cronobiologia e Sono do Hospital de Clinicas de Porto Alegre; Porto Alegre, Brazil; 6Postgraduate Program in Health and Human Development, La Salle Universitary Center, Canoas, Brazil; 7Pharmacology Department, Instituto de Ciências Básicas da Saúde, UFRGS, Porto Alegre, Brazil; 8Centro de Ciências da Saúde – Departamento de Nutrição da Universidade Federal De Santa Catarina, Florianopolis, Brazil Objective: This study compared urinary 6-sulfatoxymelatonin (aMT6s) over 24 hours among fibromyalgia (FM), major depression disorder (MDD), and healthy control (HC) groups, and examined whether rhythm is correlated with depressive symptoms. To answer this question we compared the rhythm of urinary aMT6s secretion among each group in four time series: morning (06:00–12:00 hours), afternoon (12:00–18:00 hours), evening (18:00–24:00 hours), and night (24:00–06:00 hours). In the FM subjects, we assessed if the rhythm of urinary aMT6s secretion is associated with pain severity, sleep quality, number of trigger points (NTPs), and the pain pressure threshold (PPT). Patients and methods: We included 54 women, aged 18–60 years with diagnosis of FM (n=18), MDD (n=19), and HC (n =17). The 24-hour urinary aMT6s was evaluated according to four standardized periods. The assessment instruments were the Hamilton Depression Rating Scale (HDRS), Pittsburgh Sleep Quality Index, and Fibromyalgia Impact Questionnaire. Results: A generalized estimating equation revealed no difference in the daily load of aMT6s secretion among the three groups (P=0.49). However, at the daily time (06:00–18:00 hours), the load secretion of aMT6s reached 41.54% and 60.71% in the FM and MDD, respectively, as compared to 20.73% in the HC (P

Submitted by DSpace Unilasalle (dspace@unilasalle.edu.br) on 2021-08-03T14:26:28Z No. of bitstreams: 1 vlscarabelot.pdf: 1493043 bytes, checksum: c351c068a10bffcb0a6339fc1991fc24 (MD5) Made available in DSpace on 2021-08-03T14:26:28Z (GMT). No. of bitstreams: 1 vlscarabelot.pdf: 1493043 bytes, checksum: c351c068a10bffcb0a6339fc1991fc24 (MD5) Previous issue date: 2021 Background: Transcranial direct-current stimulation (tDCS) is a noninvasive method of brain stimulation suggested as a therapeutic tool for pain and is related to the reversal of maladaptive plasticity associated with chronic pain. Objectives: This study investigated the effect of tDCS, a non-pharmacological therapy, on local mechanical hyperalgesia, and remote thermal hyperalgesia in rats submitted to orofacial inflammatory pain model, by facial von Frey and hot plate tests, respectively. In addition, we evaluated levels of BDNF, NGF, IL-10 and IL-6 in the brainstem and blood serum of these animals at 24 hours and 7 days after the end of tDCS treatment. Methods: Rats were subjected to temporomandibular joint pain and treated with tDCS. The animals were divided into control, pain and pain + treatment groups. Mechanical and thermal hyperalgesia were evaluated at baseline, 7 days after administration of complete Freund's adjuvant, and immediately, 24 hours, and 7 days after the tDCS treatment. Neuroimmunomodulators levels were determined by ELISA. Statistical analyses were performed by (GEE)/Bonferroni (behavioural tests), three-way ANOVA/SNK (neurochemical tests) and Kruskal-Wallis (histological analysis). Results: Transcranial direct-current stimulation reduced mechanical and thermal hyperalgesia (P < 0.01). We observed interaction between factors (pain and treatment) increasing brainstem BDNF (P < 0.01) and NGF (P < 0.05) levels. Furthermore, we found an increase in IL-6 and IL-10 levels in the brainstem at 24 hours and 7 days after tDCS, respectively. Conclusion: We showed that tDCS reduces thermal and mechanical hyperalgesia induced by orofacial pain until 7 days after treatment. These findings demonstrate that tDCS was effective in the control of orofacial inflammatory pain.

Submitted by DSpace Unilasalle (dspace@unilasalle.edu.br) on 2021-08-02T18:59:56Z No. of bitstreams: 1 lfmedeiros.etal.pdf: 929739 bytes, checksum: ce360721638f449ca416ded050bd121b (MD5) Made available in DSpace on 2021-08-02T18:59:56Z (GMT). No. of bitstreams: 1 lfmedeiros.etal.pdf: 929739 bytes, checksum: ce360721638f449ca416ded050bd121b (MD5) Previous issue date: 2020 Background: This study assessed the effects of an acute stress model upon the long-term hyperalgesia induced by repeated morphine administration in neonatal rats. We also evaluated neurotrophins and cytokines levels; expressions of adenosine and acetylcholine receptors, and acetylcholinesterase enzyme at the spinal cord. Material and methods: Male Wistar rats were subjected to morphine or saline administration from P8 to P14. Thermal hyperalgesia and mechanical hyperesthesia were assessed using the hot plate (HP) and von Frey (vF) tests, respectively, at postnatal day P30 and P60. After baseline measurements, rats were subjected to a single exercise session, as an acute stress model, at P30 or P60. We measured the levels of BDNF and NGF, interleukin-6, and IL-10 in the cerebral cortex and the brainstem; and the expression levels of adenosine and muscarinic receptors, as well as acetylcholinesterase (AChE) enzyme at the spinal cord. Results: A stress exercise session was not able to revert the morphine-induced hyperalgesia. The morphine and exercise association in rats induced a decrease in the neurotrophins brainstem levels, and A1 , A2A , A2B receptors expression in the spinal cord, and an increase in the IL-6 cortical levels. The exercise reduced M2 receptors expression in the spinal cord of naive rats, while morphine prevented this effect. Conclusions: Single session of exercise does not revert hyperalgesia induced by morphine in rats; however, morphine plus exercise modulate neurotrophins, IL-6 central levels, and expression of adenosine receptors.

Submitted by DSpace Unilasalle (dspace@unilasalle.edu.br) on 2021-08-02T19:33:06Z No. of bitstreams: 1 emmcallai.etal.pdf: 723610 bytes, checksum: 5648f7e0feb38c625b2dbd954500028c (MD5) Made available in DSpace on 2021-08-02T19:33:06Z (GMT). No. of bitstreams: 1 emmcallai.etal.pdf: 723610 bytes, checksum: 5648f7e0feb38c625b2dbd954500028c (MD5) Previous issue date: 2019 Objective Our objective was to evaluate the Transcranial direct current stimulation (tDCS) effect on facial allodynia induced by chronic constriction of the infraorbital nerve (CCI-ION) and on the brainstem levels of TNF-α, NGF, IL-10, and serum LDH in rats. Methods Rats were exposed to the CCI-ION model. Facial allodynia was assessed by von Frey filaments test at baseline, 3, 7, 10, and 14 days postsurgery and 24 hr and 7 days after the bimodal tDCS sessions for 20 min/day/8 days. Results Chronic constriction of the infraorbital nerve induced a significant decrease in the mechanical threshold 14 days after surgery. This effect was reversed by tDCS treatment, with the mechanical threshold returning to basal levels at 24 hr after the end of the treatment and it persisted for 7 days after the end of the treatment. tDCS also decreased LDH serum levels compared to those in the control group. There was an interaction between pain and treatment with respect to brainstem levels of NGF, TNF-α, and IL-10. Conclusion Chronic constriction of the infraorbital nerve model was effective in establishing trigeminal neuropathic pain on 14 days after surgery, and tDCS reduced allodynia and LDH serum levels and promoted alterations in NGF, TNF-α, and IL-10 brainstem levels. Thus, we suggest that tDCS may be a potential therapy in the trigeminal pain treatment.

Submitted by DSpace Unilasalle (dspace@unilasalle.edu.br) on 2021-09-14T21:45:40Z No. of bitstreams: 1 gbserrano.et.al.pdf: 3045186 bytes, checksum: 2e4a6d8fca2af7900fe50d50ac1eb3fd (MD5) Made available in DSpace on 2021-09-14T21:45:40Z (GMT). No. of bitstreams: 1 gbserrano.et.al.pdf: 3045186 bytes, checksum: 2e4a6d8fca2af7900fe50d50ac1eb3fd (MD5) Previous issue date: 2019 Objectives: This paper aims to determine if hypnotic analgesia suggestion and transcranial direct-current stimulation (tDCS) have a differential effect on pain perception. We hypothesized that transcranial direct-current stimulation would be more effective than hypnotic analgesia suggestion at changing the descending pain modulating system, whereas the hypnotic suggestion would have a greater effect in quantitative sensory testing. Design: This is a randomized, double blind and crossover trial. Settings: All stages of this clinical trial were performed at the Laboratory of Pain and Neuromodulation of the Hospital de Clínicas de Porto Alegre. Subjects: Were included 24 healthy females aged from 18 to 45 years old, with a high susceptibility to hypnosis, according to the Waterloo-Stanford Group Scale of Hypnotic Susceptibility, Form C (15). Methods: The subjects received a random and crossover transcranial direct-current stimulation over the dorsolateral prefrontal cortex (2 mA for 20 min) and hypnotic analgesia (20 min). Results: Only hypnotic suggestion produced changes that are statistically significant from pre- to post-intervention in the following outcomes measures: heat pain threshold, heat pain tolerance, cold pressure test, and serum brain-derivate-neurotrophic-factor. The analysis showed a significant main effect for treatment (F = 4.32; P = 0.04) when we compared the delta-(1) of conditioned pain modulation task between the transcranial direct-current stimulation and hypnotic suggestion groups. Also, the change in the brain-derivate-neurotrophic-factor was positively correlated with the conditioned pain modulation task. Conclusion: The results confirm a differential effect between hypnotic suggestion and transcranial direct-current stimulation on the pain measures. They suggest that the impact of the interventions has differential neural mechanisms, since the hypnotic suggestion improved pain perception, whereas the transcranial direct-current stimulation increased inhibition of the descending pain modulating system. Clinical Trial Registration: www.ClinicalTrials.gov, identifier NCT03744897. Perspective: These findings highlight the effect of hypnotic suggestion on contraregulating mechanisms involved in pain perception, while the transcranial direct-current stimulation increased inhibition of the descending pain modulating system. They could help clinicians comprehend the mechanisms involved in hypnotic analgesia and transcranial direct-current stimulation and thus may contribute to pain and disability management.