Iraci Lucena da Silva Torres

Universidade Federal do Rio Grande do Sul | UFRGS · Faculdade de Medicina

Background & Objective: No specific therapy is available for metabolic dysfunction-associated fatty liver disease (MAFLD). We investigated nicotinamide riboside (NR) and dietary restriction (DR) effects in liver lipids, inflammation, and histology, intestinal permeability, and gut microbiota (GM) in a cafeteria diet (CAFD)-induced obesity model. Me...

Noninvasive neuromodulation techniques are on the rise as adjuvant alternatives for the treatment of chronic pain. In this way, Transcranial Direct Current Stimulation (tDCS) has been demonstrated as a viable non-pharmacological method for the treatment of Neuropathic Pain (NP) in humans. In a recent review, Caumo and colleagues have shown evidence...

Objective: We compare the effect of HAS, a-tDCS on the left dorsolateral prefrontal cortex (l-DLPFC), and rest-testing on pain measures [(cold pressor test (CPT) (primary outcome) and heat pain threshold]. We also compare their effects on the motor evoked potential (MEP) (primary outcome), short intracortical inhibition (SICI), intracortical facil...

Background: Circadian rhythm alterations have been reported in fibromyalgia (FM) and depression. Peripheral body temperature (PBT) is a reliable measure of the circadian system, so we compared the PBT rhythm between persons with FM and controls. We evaluated PBT correlation with depression symptoms and pain severity in women with FM. Methods: We...

Background: Resting-state functional connectivity (rs-FC) may aid in understanding the link between pain-modulating brain regions and the descending pain modulatory system (DPMS) in fibromyalgia (FM). This study investigated whether the differences in rs-FC of the primary somatosensory cortex in responders and non-responders to the conditioned pai...

Background Transcranial Direct Current Stimulation (tDCS) is a promising approach to improving fibromyalgia (FM) symptoms, including cognitive impairment. So, we evaluated the efficacy and safety of home-based tDCS in treating cognitive impairment. Besides, we explored if the severity of dysfunction of the Descendant Pain Modulation System (DPMS) p...

Trigeminal neuropathic pain (TNP) is an intense pain condition characterized by hyperalgesia and allodynia; however, its neural mechanisms are not completely understood. Its management is complex, and studies that investigate its biochemical mechanisms are important for improving clinical approaches. This study aimed to evaluate the involvement of...

Fibromyalgia is a heterogenous primary pain syndrome whose severity has been associated with descending pain modulatory system (DPMS) function and functional connectivity (FC) between pain processing areas. The brain-derived neurotrophic factor (BDNF) Val66Met single nucleotide polymorphism has been linked to vulnerability to chronic pain. In this...

Background The successful regulation of sensory input to the central nervous system depends on the descending pain modulatory system (DPMS). For the effective regulation of sensory input to the central nervous system and behavioral responses to pain, the DPMS is required. Its connection to fibromyalgia (FM)-related cognitive dysfunction has not yet...

Introduction: Considering the lack of specific treatments to neuropathic pain, this study aimed to evaluate the effect of a single dose adenosine A3 receptor IB-MECA in the inflammatory and neurotrophic parameters of rats submitted to a neuropathic pain model. Methods: 64 adults male Wistar rats were used. Neuropathic pain was induced by the chroni...

Introduction: The association between descending pain modulatory system (DPMS) dysfunction and fibromyalgia has been previously described, but more studies are required on its relationship with aberrant functional connectivity (FC) between the motor and prefrontal cortices. Objectives: The objective of this cross-sectional observational study wa...

Transcranial direct current stimulation (tDCS) has demonstrated clinical benefits such as analgesia, anti-inflammatory, and neuroprotective effects. However, the mechanisms of action of a single tDCS session are poorly characterized. The present study aimed to evaluate the effects of a single tDCS session on pain sensitivity, inflammatory parameter...

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-...

Maternal deprivation refers to the disruption of the mother–pup/mother–child interaction in the first days/weeks of life. Translational models for maternal deprivation/separation experiences of human infants in neonatal intensive care units are being used worldwide by several research groups and have shown, among other consequences, to cause change...

Neuropathic pain (NP) is related to the presence of hyperalgesia, allodynia and spontaneous pain, affecting 7–10% of the general population. Repetitive transcranial magnetic stimulation (rTMS) is being applied for NP relief especially in patients with refractory pain.Objective: As NP response to existing treatments is often insufficient, we aimed t...

Spectral power density (SPD) indexed by electroencephalogram (EEG) recordings has recently gained attention in elucidating neural mechanisms of chronic pain syndromes and medication use. We compared SPD variations between 15 fibromyalgia (FM) women in use of opioid in the last three months (73.33% used tramadol) with 32 non-users. EEG data were obt...

This randomized, double-blind trial tested the hypothesis that twenty sessions of home-based anodal(a)-transcranial direct current stimulation (tDCS) (2mA for 20 min) bifrontal, with anodal on the left dorsolateral prefrontal cortex (l-DLPFC) would be better than sham-(s)-tDCS to reduce scores on Pain Catastrophizing Scale (PCS) and disability-rela...

The aim of this study was to evaluate the effects of transcranial direct current stimulation (tDCS) on anxiety-like behavior and neural parameters in rats with chronic pain exposed to alcohol. Thirty-six adult male Wistar rats were randomly assigned to control (CT), neuropathic pain (NP), NPtDCS, NP + alcohol (NPAL), or NPALtDCS groups, subjected t...

Objective: To assess disordered eating, hunger and satiety perceptions in women with fibromyalgia (FM) compared to healthy controls (HC) and their association with biomarkers of brain plasticity (brain-derived neurotrophic factor (BDNF) and S100 calcium-binding protein B (S100B)). Methods: Cross-sectional exploratory study. The sample included F...

Obesity treatments, such as calorie restriction (CR), eventually lead to muscle wasting and higher rates of neuroinflammation, whereas hypothalamic inflammatory conditions impair body weight (BW) control. Nicotinamide riboside (NR) has been proposed against obesity but with little evidence on skeletal muscle tissue (SMT) and neuroinflammation. Ther...

The delta value of oxyhemoglobin (Δ-HbO) determined by functional near-infrared spectroscopy at prefrontal cortex (PFC) and motor cortex (MC) based on primary (25 °C) and secondary (5 °C) thermal stimuli presented a larger peak latency at left MC in fibromyalgia than in controls. The difference between HbO concentration 15 s after the thermal stimu...

Gamma-decanolactone (GD) has been shown to reduce epileptic behavior in different models, inflammatory decreasing, oxidative stress, and genotoxic parameters. This study assessed the GD effect on the pentylenetetrazole (PTZ) model after acute and subchronic treatment. We evaluated the expression of the inflammatory marker cyclooxygenase-2 (COX-2),...

Neuropathic pain (NP) is characterized by the presence of spontaneous pain, allodynia and hyperalgesia. Repetitive transcranial magnetic stimulation (rTMS) is one of neuromodulatory techniques that induces satisfactory NP relief, including that from refractory pain patients. The objective of this study was to evaluate rTMS treatment over long term...

Introduction: The physiopathology of central post-stroke pain (CPSP) is poorly understood, which may contribute to the limitations of diagnostic and therapeutic advancements. Thus, the current systematic review was conducted to examine, from an integrated perspective, the cortical neurophysiological changes observed via transcranial magnetic stimul...

BACKGROUND AND OBJECTIVES The expression of nerve growth factor (NGF) in the large-size neurons may represent a key role in the neuronal synaptic plasticity and re-organization of neuronal function after a nerve injury. Transcranial direct current stimulation (tDCS) is a non-invasive method of cerebral stimulation and represents a promising tool to...

The impaired cortical function likely plays a critical role in chronic pain maintenance and fibromyalgia symptoms. Functional connectivity (FC), as assessed by functional near-infrared spectroscopy (fNIRS), is a promising approach that evaluates cortical activation through hemodynamic response estimation. This study compared the FC of bilateral mot...

This study aimed to evaluate the effects of repeated bimodal transcranial direct current stimulation (tDCS) on alcohol consumption and immunohistological and neurochemical parameters in nerve-injured rats. Forty-eight adult male Wistar rats were distributed into six groups: control, neuropathic pain (NP)+sham-tDCS, NP+alcohol+sham-tDCS, alcohol+sha...

Obesity is key to liver steatosis development and progression. Transcranial direct current stimulation (tDCS) is a promising tool for eating disorders management but was not yet evaluated in steatosis. This study investigated tDCS’ effects on liver steatosis and inflammation in an experimental obesity model. Male Wistar rats (60 days-old) were rand...

Ultra-processed food consumption, which is highly palatable, rich in fat, sugar, and salt causes uncontrolled food intake and has contributed to a sharp increase in obesity worldwide. This study evaluated the effects of soft drink and/or ultra-processed food intake on eating behavior and metabolic parameters in rats fed with a cafeteria diet. Male...

Neuropathic pain (NP) is related to the presence of hyperalgesia, allodynia, and spontaneous pain, affecting 7%–10% of the general population. Repetitive transcranial magnetic stimulation (rTMS) is applied for NP relief, especially in patients with refractory pain. As NP response to existing treatments is often insufficient, we aimed to evaluate rT...

We compared the activation pattern at the motor cortex (MC and prefrontal cortex (PFC) based on the delta value (Δ) of oxy-hemoglobin (HbO) by functional near-infrared spectroscopy (fNIRS). We examined the relationship of the ΔHbO based on the peaks at 5°C and 25°C by right-hand immersion in water in 22 fibromyalgia and 19 controls. Fibromyalgia sh...

The impaired cortical function likely plays a critical role in chronic pain maintenance and fibromyalgia symptoms. While the functional connectivity (FC), as assessed by functional near-infrared spectroscopy (fNIRS), is a promising approach that evaluates cortical activation through hemodynamic response estimation. Thus, this study compared the FC...

Anxiety disorders cause distress and are commonly found to be comorbid with chronic pain. Both are difficult-to-treat conditions for which alternative treatment options are being pursued. This study aimed to evaluate the effects of transcranial direct current stimulation (tDCS), treadmill exercise, or both, on anxiety-like behavior and associated g...

BACKGROUND AND OBJECTIVES: To pursue safer and more effective treatments for rheumatoid arthritis, the effect of dexamethasone treatment (DEX, 0.25mg/kg) combined with transcranial direct current stimulation (tDCS) in the behavior and neurochemical parameters of arthritic rats was evaluated. METHODS: Thirty-six Wistar rats were divided into four g...

This study aimed to evaluate the effect of a single administration of IB-MECA, an A3 adenosine receptor agonist, upon the nociceptive response and central biomarkers of rats submitted to chronic pain models. A total of 136 adult male Wistar rats were divided into two protocols: (1) chronic inflammatory pain (CIP) using complete Freund’s adjuvant an...

Background To assess the psychometric properties, including internal consistency, construct validity, criterion validity, criterion-group validity, and responsiveness, the Reviewed McGill Quality of Life Questionnaire (MQOL-R), into Brazilian Portuguese-(BrP). Also, to analyze the relationship of the BrP-MQOL-R with the scores on the Karnofsky Perf...

Neuromodulatory techniques have been studied to treat drug addiction or compulsive eating as well as different chronic pain conditions, such as neuropathic and inflammatory pain in the clinical and preclinical settings. In this study, we aimed to investigate the effect of transcranial direct current stimulation (tDCS) on the association of alcohol...

Aims NAD-based therapeutic strategies are encouraged against obesity and heart disease. Our study, therefore, aimed to investigate the effects of nicotinamide riboside (NR), isolated or combined with caloric restriction (CR), both approaches well-known for stimulating NAD levels, on adiposity parameters, cardiometabolic factors and cardiac oxidativ...

Introduction: Although binge eating disorder (BED) is an eating disorder and obesity is a clinical disease, it is known that both conditions present overlapped symptoms related to, at least partially, the disruption of homeostatic and hedonistic eating behavior pathways. Therefore, the understanding of neural substrates, such as the motor cortex ex...

Objectives: Caffeine is extensively consumed as a psychostimulant drug, acting on A1 and A2A adenosine receptors blockade. Chronic exposure to caffeine during gestation and breast-feeding may be involved in infant rat's behavioral and biochemical alterations. Our goal was to evaluate the effect of chronic caffeine exposure during gestation and bre...

Introduction: The transcranial direct current stimulation (tDCS) is a neuromodulatory technique with the potential to decrease pain scores and to improve chronic pain treatment. Although age is an essential factor that might impact the tDCS effect, most studies are solely conducted in adults. Therefore, the age limitation presents a critical resear...

Objective: We evaluated whether active(a)-tDCS combined with hypnotic analgesia suggestion (HS) would be more effective than a single active(a)-tDCS, and/or sham-(s)-tDCS and s-tDCS/HS on the following outcomes: function of descending pain modulatory system (DPMS) during the conditioned pain modulation test (CPM-test) (primary outcome), heat pain...

Literature shows that gestational and/or lactational exposure to hypercaloric diets induces long term effects on eating behavior and the involvement of neurochemical mechanisms. We hypothesized that the effects of hypercaloric diets in early development phases can precede an overweight or an obesity status. Theaim of the present study was to evalua...

In the present study, we investigated the effect of repeated neonatal morphine exposure and/or maternal deprivation(MD) on the nociceptive response and central biomarkers’ BDNF, IL-1β, and IL-4 levels at postnatal days 16(PND16), 30(PND30), and 60(PND60). At birth, the litters were standardized to contain 8 pups/dam (n = 58). From PND1 to PND10, th...

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 spinal cord. Material and methods Male Wista...

Background/aim: Magnetic stimulation is used in the treatment of a diversity of diseases, but a complete understanding of the underlying mechanisms of action requires further investigation. We examined the effect of static magnetic stimulation (SMS) in different cell lines. Materials and methods: A culture plate holder with attached NeFeB magnet...

Background: To assess the psychometric properties, including internal consistency, construct validity, criterion validity, criterion-group validity, and responsiveness, the Reviewed McGill Quality of Life Questionnaire (MQOL-R), into Brazilian Portuguese-(BrP). Also, to analyze the relationship of the BrP-MQOL-R with the scores on the Karnofsky Per...

Background: To assess the psychometric properties, including internal consistency, construct validity, criterion validity, criterion-group validity, and responsiveness, the Reviewed McGill Quality of Life Questionnaire (MQOL-R), into Brazilian Portuguese-(BrP). Also, to analyze the relationship of the BrP-MQOL-R with the scores on the Karnofsky Per...

The givenname "Paola" of the author Paola Haack Amaral Roppa (Roppa, P.H.A.) should be corrected to read Ricardo Haack Amaral Roppa (Roppa, R.H.A.) as presented above.

Trigeminal neuralgia (TN) is a type of neuropathic pain characterized by intense pain; although anticonvulsants are used as an option to relieve pain, adverse side effects can decrease patient adherence. In this context, a low dose of naltrexone is effective in relieving pain in other pain conditions. Thus, the objective of the present study was to...

Despite the introduction of new antiepileptic drugs, about 30% of patients with epilepsy are refractory to drug therapy. Thus, the search for non-pharmacological interventions such as transcranial direct current stimulation (tDCS) may be an alternative, either alone or in combination with low doses of anticonvulsants. This study evaluated the effec...

Background: Age is an important factor that impacts the variability of tDCS effects. Objective/Hypothesis: To compare effects of anodal (a)-tDCS over the left dorsolateral prefrontal cortex (DLPFC), and primary motor cortex (M1) in adolescents, adults, and elderly on heat pain threshold (HPT; primary outcome) and the working memory (WM; secondary o...

Background The main symptoms of fibromyalgia comprise diffuse pain, disability, depressive symptoms, catastrophizing, sleep disruption and fatigue, associated with dysfunction of the descending pain-modulating system (DPMS). Objectives We aimed to identify patterns of main symptoms of fibromyalgia and neuroplasticity biomarkers (i.e. brain-derived...

This randomized, double-blinded, placebo-controlled trial tested the hypothesis that 20mg of melatonin before and during the first cycle of adjuvant chemotherapy for breast cancer (ACBC) reduced the side effects associated with cognitive impairment. We evaluated the effects of melatonin on cognition, depressive symptoms and sleep quality, and wheth...

Objectives: We investigated sex differences and the influence of brain-derived neurotrophic factor (BDNF) in the descending pain modulatory system (DPMS), as measured by change on the numerical pain scale (NPS; 0-10) during conditioned pain modulation (CPM task; primary outcome) and by function of the corticospinal motor pathway and heat pain thre...

Background Behavioral alterations, like mechanical and thermal hyperalgesia, and modulation of biomarkers in the peripheral and central nervous systems (CNS) are markers of chronic pain. Transcranial direct current stimulation (tDCS) with exercise is a promising therapy for pain due to its neuromodulatory capacity. Objective To assess the individu...

Anxiety is one of the most prevalent and debilitating psychiatric conditions worldwide. Pharmaco- and psycho-therapies have been employed in the treatment of human anxiety to date. Yet, either alone or in combination, unsatisfactory patient outcomes are prevalent, resulting in a considerable number of people whose symptoms fail to respond to conven...

Maternal deprivation(MD) in rodents is used to simulate human-infant early life stress, which leads to neural, hormonal, and behavioral alterations. Palatable food(PF) can reduce the stress response, and individuals use it as a self-applied stress relief method. Thus, the present study aimed to evaluatethe effect of the association between MD in th...

Transcriptomics and candidate gene/protein expression studies have indicated several biological processes modulated by methylphenidate (MPH), widely used in attention-deficit/hyperactivity disorder (ADHD) treatment. However, the lack of a differential proteomic profiling of MPH treatment limits the understanding of the most relevant mechanisms by w...

Background: Opioid long-term therapy can produce tolerance, opioid-induced hyperalgesia (OIH), and it induces dysfunction in pain descending pain inhibitory system (DPIS). Objectives: This integrative review with meta-analysis aimed: (i) To discuss the potential mechanisms involved in analgesic tolerance and opioid-induced hyperalgesia (OIH). (ii)...