Terapia Multimodal na fibromialgia: Estudos pré-clínico do efeito antinociceptivo e antidepressivo de diferentes modalidades terapêuticas em modelo de fibromialgia em ratas

Abstract

Fibromyalgia (FM) is a chronic pain syndrome with a multifactorial etiopathogenesis that is not fully understood. This condition affects more women and is characterized by widespread musculoskeletal pain, as well as specific pain at palpation points, fatigue, sleep disorders, functional disorders, and even psychological symptoms. The etiology of fibromyalgia is not yet fully understood, so treatment alternatives, for example, have little efficacy and many adverse effects. Therefore, it is essential to investigate effective therapies with few adverse effects. Multimodal therapy (MT) has been investigated as the first line of treatment for fibromyalgia. Multimodal therapy consists of a combination of pharmacological and non-pharmacological therapies as a therapeutic source. Thus, the present study aims to investigate the analgesic and antidepressant effects of different therapeutic modalities in the experimental model of fibromyalgia. For this purpose, female Wistar rats with an average weight between 190 and 220 g and 5-6 weeks of age were used. The reserpine-induced myalgia (RIM) model was performed by administering reserpine (0.7 mg/kg intraperitoneally – i.p. for 3 consecutive days). The proposed treatments were performed in isolation and in combination, namely: strength training (ST), electroacupuncture (EA) and CBD oil (CBD). ST consists of climbing a vertical ladder (3 sets of 4 repetitions). The EA protocol consists of stimulating acupuncture points E36 (Zusanli) and BP6 (Sanyinjiao), frequency of 2 Hz, pulse width of 500 μs, duration of 20 minutes, and intensity adjusted to the limits of muscle contraction (between 0.5 to 1.5 mV). Finally, full spectrum CBD oil was administered orally in a volume of 1 mg/kg. The evaluations were performed weekly and consisted of analyzing the parameters of mechanical hyperalgesia assessed by the von Frey filament test, thermal allodynia by the Acetone Test and depressive-like behavior by the Tail Suspension Test (TSC). The results showed significant improvements in the scores of mechanical hyperalgesia, thermal allodynia and depressive-like behavior in animals submitted to isolated protocols, but with particularities between the days evaluated. In addition, the TM groups obtained even more promising results in the evaluations. Thus, this study determined that isolated and associated therapies are effective in the management of fibromyalgia in a preclinical model. However, further studies are needed on the mechanisms and repercussions involved.