Melatonin Potentiates Exercise-Induced Increases in Skeletal Muscle PGC-1α and Optimizes Glycogen Replenishment

Abstract

Compelling evidence has demonstrated the effect of melatonin on exhaustive exercise tolerance and its modulatory role in muscle energy substrates at the end of exercise. In line with this, PGC-1α and NRF-1 also seem to act on physical exercise tolerance and metabolic recovery after exercise. However, the literature still lacks reports on these proteins after exercise until exhaustion for animals treated with melatonin. Thus, the aim of the current study was to determine the effects of acute melatonin administration on muscle PGC-1α and NRF-1, and its modulatory role in glycogen and triglyceride contents in rats subjected to exhaustive swimming exercise at an intensity corresponding to the anaerobic lactacidemic threshold (iLAn). In a randomized controlled trial design, thirty-nine Wistar rats were allocated into four groups: control (CG = 10), rats treated with melatonin (MG = 9), rats submitted to exercise (EXG = 10), and rats treated with melatonin and submitted to exercise (MEXG = 10). Forty-eight hours after the graded exercise test, the animals received melatonin (10 mg/kg) or vehicles 30 min prior to time to exhaustion test in the iLAn (tlim). Three hours after tlim the animals were euthanized, followed by muscle collection for specific analyses: soleus muscles for immunofluorescence, gluteus maximus, red and white gastrocnemius for the assessment of glycogen and triglyceride contents, and liver for the measurement of glycogen content. Student t-test for independent samples, two-way ANOVA, and Newman keuls post hoc test were used. MEXG swam 120.3% more than animals treated with vehicle (EXG; p < 0.01). PGC-1α and NRF-1 were higher in MEXG with respect to the CG (p < 0.05); however, only PGC-1α was higher for MEXG when compared to EXG. Melatonin reduced the triglyceride content in gluteus maximus, red and white gastrocnemius (F = 6.66, F = 4.51, and F = 6.02, p < 0.05). The glycogen content in red gastrocnemius was higher in MEXG than in CG (p = 0.01), but not in EXG (p > 0.05). In conclusion, melatonin was found to enhance exercise tolerance, potentiate exercise-mediated increases in PGC-1α, decrease muscle triglyceride content and increase muscle glycogen 3 h after exhaustive exercise, rapidly providing a better cellular metabolic environment for future efforts.

Efeito da melatonina na histofisiologia do fígado de ratos adolescentes expostos ao álcool

“…Estudos anteriores apontaram que a melatonina tem a capacidade de aumentar o conteúdo de glicogênio hepático (FARIA et al, 2022), e esse aumento pode ser explicado pela melhoria na captação de glicose nos tecidos e/ou na sensibilidade à insulina por meio de uma via dependente. do Akt ativada via receptor de melatonina (SHIEH et al, 2009).…”

Effect of melatonin on the liver histophysiology of adolescent rats exposed to alcohol

“…As for the reserve of sugar in the liver, the alcohol + melatonin group presented a glycogen reserve close to the control group. Previous studies have pointed out that melatonin has the ability to increase hepatic glycogen content (FARIA et al, 2022), and this increase can be explained by the improvement in tissue glucose uptake and/or insulin sensitivity through a dependent pathway. of Akt activated via melatonin receptor (SHIEH et al, 2009).…”

Ethological and immunological interrelations in experimental desynchronosis under fluorescent lighting conditions

“…Отмечено, что они реализуются преимущественно за счет гуморальных влияний [20,22]. Клетки микроглиии астроциты являются основными иммунными эффекторными клетками мозга и наряду с цитотоксическими Т-клетками играют важную роль в нейрогенезе и формировании пространственной памяти [23]. В присутствии активирующего стимула клетки микроглии модулируют иммунный ответ, через секрецию фактора некроза опухоли-α (TNF-α), IL-1, IL-4, IL-6, INF-γ [19,21,24].…”