Percorrer por autor "Moraes, Alexa Alves de"
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- Combined nandrolone and resistance training induced cardiac remodelling and oxidative stress despite enhanced cardiomyocyte contractilityPublication . Moraes, Alexa Alves de; Suarez, Pedro Zavagli; Quintão, Arthur Eduardo de Carvalho; Fontes, Beatriz Lana; Costa, Sebastião Felipe Ferreira; Rocha, Carolina Camargos; Soares, Leôncio Lopes; Leite, Luciano Bernardes; Oliveira, Leandro Licursi; Reis, Emily Correna Carlo; Oliveira, Edilamar Menezes de; Forte, Pedro; Natali, Antônio José; Carneiro-Júnior, Miguel AraújoNandrolone decanoate (ND) is widely used by individuals engaged in resistance training (RT), yet their combined effects on cardiac function remain unclear. Objective To investigate the effects of RT and ND on cardiac structure and function, cellular contractility, Ca-2 (+) -handling protein expression, and redox balance in rats. Methods Thirty-two male Wistar rats were assigned to four groups: control (C), trained (C-T), ND (N), and trained ND (N-T). Animals received ND or saline for eight weeks, and RT was performed 3 x /week. Cardiac function was assessed by echocardiography, and isolated cardiomyocytes from the left and right ventricles (LV and RV) were evaluated for contractile function. Protein expression of Ca-2 (+) -handling regulators and oxidative stress markers was quantified. Results N-T increased LV and RV diameters by 25% and 33%, septal thickness by 41.7%, and reduced ejection fraction by 12.3% compared to N (p < 0.05). LV cardiomyocytes increased width by 29% and volume by 23% in N-T versus C-T (p <= 0.04). In LV, N-T showed greater contraction amplitude and velocity at 5 Hz (p = 0.04) and increased relaxation velocity at 1, 3, and 5 Hz (p < 0.01), with shorter time to peak contraction and 50% relaxation at 1 Hz versus N (p = 0.04). In RV, N-T increased contraction amplitude and velocity at 1 and 5 Hz, reduced time to peak at 1 and 3 Hz, shortened relaxation time at 1 Hz, and showed higher relaxation velocity than N and C-T (p < 0.02). Molecular analyses revealed reduced RyR2 expression (25% in LV and 9% in RV) and a 41% decrease in LV phospholamban in N-T versus C-T (p < 0.05). N-T also exhibited higher LV malondialdehyde compared to C-T (p = 0.03). Conclusion ND combined with RT induced adverse cardiac remodeling and impaired ventricular function, despite enhanced cardiomyocyte contractility, and intensified molecular and oxidative disturbances, indicating a maladaptive cardiac response. This is the first study to demonstrate regional differences in contractility and redox balance of isolated ventricular cardiomyocytes under ND plus RT.
- Influence of prostaglandin F2alfa dosage and semen storage time on cervical artificial insemination of ewesPublication . Paula, Isabela Mendonça Leon de; Moraes, Alexa Alves de; Santos, Liliana; Quintas, Helder; Valentim, Ramiro; Silva, Daiane; Sociedade Brasileira de ZootecniaFixed-time artificial insemination (FTAI) is one of the main tools to achieve genetic improvement in sheep production and its implementation is facilitated by methods of estrus synchronization and ovulation’ stimulation. For vaginal or cervical artificial insemination, fresh or cooled semen is the most used, resulting in acceptable pregnancy rates. The main purposes of this research were to evaluate the effectiveness of a reduced dose of prostaglandin F2α (PGF2α) in the estrus synchronization protocol and to verify the influence of semen storage time at 5oC on the sheep conception rates. This study was conducted at Bragança Polytechnic University between April and June 2023. Sixty-six Churra Galega Bragançana Branca breed ewes were used. The short progestogen protocol involved the use of a vaginal device containing 0.35 g of progesterone for seven days. Simultaneously with the device insertion, half of the ewes received an intramuscular (IM) injection of 75 μg of PGF2α, while the other half received 100 μg. Upon the removal of the device, all ewes received a 500 IU IM injection of equine chorionic gonadotropin (eCG). Semen was collected from two ram donors through electroejaculation and seminal analyzes were performed using a computer assisted semen analysis (CASA). Semen was diluted in INRA 96 extender and 0.25 mL straws containing 250 x 106 sperm each were produced. The straws’ temperature was reduced until 5oC in a refrigerated water bath (-0.27oC/min). Semen was stored at 5oC, 0-day, 1 day or 2 days after cooling. Fifty-six hours after the eCG injection, all ewes were cervical inseminated by the FTAI method. After 41 days, rectal ultrasound was used to detect pregnancy rate. In order to identify statistically significant variations, variance analyses were conducted. The comparison between means was performed using the Bonferroni/Dunn test at 95% of probability. The Chi-square test was done to compare frequencies. It was determined that the use of 100 μg of PGF2α was more effective (P<0.05) than 75 μg, with conception rates of 85% and 73%, respectively. PGF2α is a hormone with high cost, then to reduce the dosage/animal/cycle is interesting for the sheep producers, but unfortunately the reduction of 25% compromises the pregnancy rate. The storage time (0-day, 1 day and 2 days) did not significantly impact the conception results (P>0.05), with rates of 81%, 83% and 73%, respectively. Therefore, it was concluded that the 100 μg of PGF2α protocol generates a higher pregnancy rate than the 75 μg of PGF2α protocol and it is possible to use ram semen until two days after cooling at 5oC without any negative impact on the conception rate of Churra Galega Bragançana ewes.
- Resistance Training Before Hyperalgesia Induction Promotes Analgesic Effects Through Central and Peripheral Biomarker Modulation in an Experimental Fibromyalgia-like ModelPublication . Chiapeta, Andrês Valente; Oliveira, Leandro Licursi; Leite, Luciano Bernardes; Silva, Bruna Aparecida Fonseca da; Costa, Sebastião Felipe Ferreira; Soares, Leôncio Lopes; Moraes, Alexa Alves de; Drummond, Lucas Rios; Forte, Pedro; Natali, Antônio José; Carneiro-Júnior, Miguel AraújoFibromyalgia is a chronic syndrome characterized by widespread pain and complex pathophysiology, requiring new therapeutic approaches. This study aims to investigate the effects of resistance training (RT) before hyperalgesia induction on pain sensitivity, IL-6 and IL-10 expression in skeletal muscle, and thalamic serotonin levels in a fibromyalgia (FM)-like rat model. Methods: Wistar female rats aged 12 months were divided into four groups: untrained neutral saline (UNS), untrained acid saline (UAS), RT neutral saline (RTN), and RT acid saline (RTA). Both the RTN and RTA groups were subjected to an RT protocol comprising vertical ladder climbing three times a week throughout 14 weeks. The UAS and RTA groups received 100 mu L of neutral, sterile saline (pH 4.0) in the left gastrocnemius muscle, while the UNS and RTN groups received 100 mu L of neutral saline (pH 7.4). Mechanical hyperalgesia was assessed using Von Frey's electronic esthesiometer. Expression of interleukins 6 (IL-6) and 10 (IL-10) was analyzed in skeletal muscle, and serotonin expression was quantified in the thalamus. Results: After hyperalgesia induction, the RT groups demonstrated higher paw withdrawal thresholds than the UAS group (p < 0.05). Both IL-6 and IL-10 expression was lower in the RTA group compared to the UAS group (p < 0.05). Thalamic serotonin expression was higher (p < 0.05) in the RTA group compared to the UAS group. Conclusion: Previous RT was able to prevent mechanical hyperalgesia experienced by rats after its induction by acid saline by preventing the increase in the IL-6 and IL-10 levels in skeletal muscle and preventing the decrease in thalamic serotonin expression.