Examinando por Autor "Cancino, Jorge"

Mostrando 1 - 4 de 4
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    Ítem
    A single bout of resistance exercise triggers mitophagy, potentially involving the ejection of mitochondria in human skeletal muscle
    (Wiley, 2024-09-24) Díaz-Castro, Francisco; Tuñón-Suárez, Mauro; Rivera, Patricia; Botella, Javier; Cancino, Jorge; Figueroa, Ana María; Gutiérrez, Juan; Cantin, Claudette; Deldicque, Louise; Zbinden-Foncea, Hermann; Nielsen, Joachim; Henríquez-Olguín, Carlos; Morselli, Eugenia; Castro-Sepulveda, Mauricio
    Aim The present study aimed to investigate the effects of a single bout of resistance exercise on mitophagy in human skeletal muscle (SkM). Methods Eight healthy men were recruited to complete an acute bout of one-leg resistance exercise. SkM biopsies were obtained one hour after exercise in the resting leg (Rest-leg) and the contracting leg (Ex-leg). Mitophagy was assessed using protein-related abundance, transmission electron microscopy (TEM), and fluorescence microscopy. Results Our results show that acute resistance exercise increased pro-fission protein phosphorylation (DRP1Ser616) and decreased mitophagy markers such as PARKIN and BNIP3L/NIX protein abundance in the Ex-leg. Additionally, mitochondrial complex IV decreased in the Ex-leg when compared to the Rest-leg. In the Ex-leg, TEM and immunofluorescence images showed mitochondrial cristae abnormalities, a mitochondrial fission phenotype, and increased mitophagosome-like structures in both subsarcolemmal and intermyofibrillar mitochondria. We also observed increased mitophagosome-like structures on the subsarcolemmal cleft and mitochondria in the extracellular space of SkM in the Ex-leg. We stimulated human primary myotubes with CCCP, which mimics mitophagy induction in the Ex-leg, and found that BNIP3L/NIX protein abundance decreased independently of lysosomal degradation. Finally, in another human cohort, we found a negative association between BNIP3L/NIX protein abundance with both mitophagosome-like structures and mitochondrial cristae density in the SkM. Conclusion The findings suggest that a single bout of resistance exercise can initiate mitophagy, potentially involving mitochondrial ejection, in human skeletal muscle. BNIP3L/NIX is proposed as a sensitive marker for assessing mitophagy flux in SkM.
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    Ítem
    Creatine supplementation prior to strength exercise training is not superior in preventing muscle mass loss compared with standard nutritional recommendations in females after bariatric surgery: a pilot study
    (Springer Nature, 2024) Díaz Pizarro, Marcelo; Pino Zúñiga, Johanna; Olivares Gálvez , Mariela; Rendón Vesga , Carolina; Luengas Tello, Rafael; Duque Seguro, Juan Camilo; Cancino, Jorge
    Background: This study examines whether creatine supplementation combined with strength training mitigates muscle mass loss in women during early rehabilitation post-bariatric surgery, as its effectiveness remains untested in this context. Methods: Fifteen women (37.8 ± 9.6 years; BMI, 38.8 ± 5.6 kg/m2) completed the intervention (creatine group = 7; placebo group = 8). Both groups followed a strength training program three times a week for 8 weeks. The dosage for both the creatine and placebo was 8 g prior to each exercise session. Body weight, skeletal muscle mass, fat mass, handgrip strength, and physical activity levels were measured before and after the intervention. Results: The creatine group showed a reduction of 9.5 ± 1.5 kg in body weight, with a 0.72 ± 0.6 kg decrease in muscle mass and an 8.64 ± 1.2 kg reduction in fat mass. The placebo group had a reduction of 9.6 ± 3.5 kg in body weight, with a 0.6 ± 1.2 kg decrease in muscle mass and an 8.88 ± 3.2 kg reduction in fat mass, without significant differences between groups (p > 0.05). Conclusion: The pre-session strength exercise training creatine supplementation is not superior to placebo regarding body weight and fat mass losses and the attenuation of muscle mass loss during the first weeks of rehabilitation following bariatric surgery.
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    Ítem
    Prescription of High-intensity aerobic interval training based on oxygen uptake kinetics
    (Thieme, 2023) Festa, Raúl Ricardo; Monsalves-Álvarez, Matías; Cancino, Jorge; Jannas-Vela, Sebastián
    Endurance training results in diverse adaptations that lead to increased performance and health benefits. A commonly measured training response is the analysis of oxygen uptake kinetics, representing the demand of a determined load (speed/work) on the cardiovascular, respiratory, and metabolic systems, providing useful information for the prescription of constant load or interval-type aerobic exercise. There is evidence that during high-intensity aerobic exercise some interventions prescribe brief interval times (<1-min), which may lead to a dissociation between the load prescribed and the oxygen uptake demanded, potentially affecting training outcomes. Therefore, this review explored the time to achieve a close association between the speed/work prescribed and the oxygen uptake demanded after the onset of high-intensity aerobic exercise. The evidence assessed revealed that at least 80% of the oxygen uptake amplitude is reached when phase II of oxygen uptake kinetics is completed (1 to 2 minutes after the onset of exercise, depending on the training status). We propose that the minimum work-time during high-intensity aerobic interval training sessions should be at least 1 minute for athletes and 2 minutes for non-athletes. This suggestion could be used by coaches, physical trainers, clinicians and sports or health scientists for the prescription of high-intensity aerobic interval training.
  • Miniatura
    Ítem
    The effects of maca (lepidium meyenii walp) on cellular oxidative stress: a systematic review and meta-analysis
    (MDPI, 2024-08-28) Huerta Ojeda, Álvaro; Rodríguez Rojas, Javiera; Cuevas Guíñez, Jorge; Ciriza Velásquez, Stephanie; Cancino, Jorge; Barahona Fuentes, Guillermo; Yeomans Cabrera, María Mercedes; Pavez, Leonardo; Jorquera Aguilera, Carlos
    Lepidium meyenii Walp (LmW) or Maca, including its bioactive components such as macamides, among others, has demonstrated antioxidant effects. However, the effect size (ES) of LmW on oxidative stress has not been qualitatively described and calculated. The primary objective of this systematic review and meta-analysis was to review and qualitatively describe the studies published up to 2023 that supplemented LmW to control cellular oxidative stress; the secondary objective was to calculate the ES of the different interventions. The search was designed following the PRISMA® guidelines for systematic reviews and meta-analyses and performed in the Web of Science, Scopus, SPORTDiscus, PubMed, and MEDLINE until 2023. The selection of studies included randomized controlled trials, with tests and post-tests, both in vitro and in vivo in animals and humans. The methodological quality and risk of bias were evaluated with the CAMARADES tool. The main variables were reduced glutathione, glutathione peroxidase, superoxide dismutase, and malondialdehyde. The analysis was conducted with a pooled standardized mean difference (SMD) through Hedges’ g test (95% CI). Eleven studies were included in the systematic review and eight in the meta-analysis. They revealed a small effect for reduced glutathione (SMD = 0.89), a large effect for glutathione peroxidase (SMD = 0.96), a moderate effect for superoxide dismutase (SMD = 0.68), and a moderate effect for malondialdehyde (SMD = −0.53). According to the results, the phytochemical compounds of LmW effectively controlled cellular oxidative stress, mainly macamides. It was also determined that a higher dose of LmW generated a greater antioxidant effect. However, information concerning humans is scarce.