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21 pages, 438 KB  
Review
Molecular Mechanisms and Clinical Implications of Complex Prehabilitation in Colorectal Cancer Surgery: A Comprehensive Review
by Jakub Włodarczyk
Int. J. Mol. Sci. 2025, 26(15), 7242; https://doi.org/10.3390/ijms26157242 - 26 Jul 2025
Viewed by 688
Abstract
Colorectal cancer (CRC) remains a leading cause of cancer morbidity and mortality worldwide, especially in older adults where frailty complicates treatment outcomes. Multimodal prehabilitation—comprising nutritional support, physical exercise, and psychological interventions—has emerged as a promising strategy to enhance patients’ resilience before CRC surgery. [...] Read more.
Colorectal cancer (CRC) remains a leading cause of cancer morbidity and mortality worldwide, especially in older adults where frailty complicates treatment outcomes. Multimodal prehabilitation—comprising nutritional support, physical exercise, and psychological interventions—has emerged as a promising strategy to enhance patients’ resilience before CRC surgery. Clinical studies demonstrate that prehabilitation significantly reduces postoperative complications, shortens hospital stays, and improves functional recovery. Nutritional interventions focus on counteracting malnutrition and sarcopenia through tailored dietary counseling, protein supplementation, and immunonutrients like arginine and glutamine. Physical exercise enhances cardiorespiratory fitness and muscle strength while modulating immune and metabolic pathways critical for surgical recovery. Psychological support reduces anxiety and depression, promoting mental resilience that correlates with better postoperative outcomes. Despite clear clinical benefits, the molecular mechanisms underlying prehabilitation’s effects—such as inflammation modulation, immune activation, and metabolic rewiring—remain poorly understood. This review addresses this knowledge gap by exploring potential biological pathways influenced by prehabilitation, aiming to guide more targeted, personalized approaches in CRC patient management. Advancing molecular insights may optimize prehabilitation protocols and improve survival and quality of life for CRC patients undergoing surgery. Full article
(This article belongs to the Section Molecular Pathology, Diagnostics, and Therapeutics)
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14 pages, 3713 KB  
Article
Titin’s Intrinsically Disordered PEVK Domain Modulates Actin Polymerization
by Áron Gellért Altorjay, Hedvig Tordai, Ádám Zolcsák, Nikoletta Kósa, Tamás Hegedűs and Miklós Kellermayer
Int. J. Mol. Sci. 2025, 26(14), 7004; https://doi.org/10.3390/ijms26147004 - 21 Jul 2025
Viewed by 407
Abstract
The multi-domain muscle protein titin provides elasticity and mechanosensing functions to the sarcomere. Titin’s PEVK domain is intrinsically disordered due to the presence of a large number of prolines and highly charged residues. Although PEVK does not have canonical actin-binding motifs, it has [...] Read more.
The multi-domain muscle protein titin provides elasticity and mechanosensing functions to the sarcomere. Titin’s PEVK domain is intrinsically disordered due to the presence of a large number of prolines and highly charged residues. Although PEVK does not have canonical actin-binding motifs, it has been shown to bind F-actin. Here, we explored whether the PEVK domain may also affect actin assembly. We cloned the middle, 733-residue-long segment (called PEVKII) of the full-length PEVK domain, expressed in E. coli and purified by using His- and Avi-tags engineered to the N- and C-termini, respectively. Actin assembly was monitored by the pyrene assay in the presence of varying PEVKII concentrations. The structural features of PEVKII-associated F-actin were studied with atomic force microscopy. The added PEVKII enhanced the initial and log-phase rates of actin assembly and the peak F-actin quantity in a concentration-dependent way. However, the critical concentration of actin polymerization was unaltered. Thus, PEVK accelerates actin polymerization by facilitating its nucleation. This effect was highlighted in the AFM images of F-actin–PEVKII adsorbed to the supported lipid bilayer. The sample was dominated by radially symmetric complexes of short actin filaments. PEVK’s actin polymerization-modulating effect may, in principle, have a function in regulating sarcomeric actin length and turnover. Altogether, titin’s PEVK domain is not only a non-canonical actin-binding protein that regulates sarcomeric shortening, but one that may modulate actin polymerization as well. Full article
(This article belongs to the Special Issue Biomolecular Structure, Function and Interactions: 2nd Edition)
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13 pages, 1118 KB  
Article
Assessing Gross Motor and Gait Function Using Hip–Knee Cyclograms in Ambulatory Children with Spastic Cerebral Palsy
by Jehyun Yoo, Juntaek Hong, Jeuhee Lee, Yebin Cho, Taekyung Lee and Dong-wook Rha
Sensors 2025, 25(14), 4485; https://doi.org/10.3390/s25144485 - 18 Jul 2025
Viewed by 445
Abstract
Weakness, spasticity, and muscle shortening are common in children with cerebral palsy (CP), leading to deficits in gross motor, gait, and selective motor functions. While traditional assessments, such as the Gross Motor Function Measure (GMFM-66), instrumented gait analysis, and the Selective Control Assessment [...] Read more.
Weakness, spasticity, and muscle shortening are common in children with cerebral palsy (CP), leading to deficits in gross motor, gait, and selective motor functions. While traditional assessments, such as the Gross Motor Function Measure (GMFM-66), instrumented gait analysis, and the Selective Control Assessment of the Lower Extremity (SCALE), are widely used, they are often limited by the resource-intensive nature of hospital-based evaluations. We employed cyclogram-based analysis, utilizing simple hip and knee joint kinematics to assess clinical measures, including GMFM-66, normalized gait speed, the gait deviation index (GDI), and the gait profile score (GPS). Principal component analysis was used to quantify the cyclogram shape characteristics. A total of 144 children with ambulatory spastic CP were included in the study. All the cyclogram parameters were significantly correlated with GMFM-66, gait speed, the GDI, and the sagittal plane subscore of the GPS for the hip and knee, with the swing phase area showing the strongest correlation. Regression models based on the swing phase area were used to estimate the GMFM-66 (R2 = 0.301) and gait speed (R2 = 0.484). The PC1/PC2 ratio showed a moderate correlation with selective motor control, as measured by the SCALE (R2 = 0.320). These findings highlight the potential of hip–knee cyclogram parameters to be used as accessible digital biomarkers for evaluating motor control and gait function in children with bilateral spastic CP. Further prospective studies using wearable sensors, such as inertial measurement units, are warranted to validate and build upon these results. Full article
(This article belongs to the Section Physical Sensors)
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10 pages, 719 KB  
Article
Effects of Clenching Strength on Step Reaction Time
by Nao Sugai, Ryo Hirabayashi, Yoshiyuki Okada, Yuriko Yoshida, Takeru Okouchi, Hirotake Yokota, Tomonobu Ishigaki, Makoto Komiya and Mutsuaki Edama
J. Funct. Morphol. Kinesiol. 2025, 10(3), 264; https://doi.org/10.3390/jfmk10030264 - 13 Jul 2025
Viewed by 397
Abstract
Background: Reaction time is analyzed in various situations in sporting events and is reported to be so important that it can make the difference between victory and defeat. This study focused on teeth clenching resulting in remote muscle activation, and examined whether it [...] Read more.
Background: Reaction time is analyzed in various situations in sporting events and is reported to be so important that it can make the difference between victory and defeat. This study focused on teeth clenching resulting in remote muscle activation, and examined whether it improves performance of reaction time. This study examined the effects of clenching and clenching strength on the systemic simple reaction time. Methods: This study included 20 healthy adults with normal clenching and a right dominant foot. The task movement for the systemic simple reaction time measurement was a 30 cm forward step. The following three clenching conditions were used: no clenching without dental contact (no-bite condition), a condition in which the participants were instructed to clench with moderate strength (moderate condition), and a condition in which the participants clenching with maximum effort (max condition). The analysis items were release time, grounding time, soleus muscle (Sol) reaction time, and masseter muscle activity. Results: The max condition significantly reduced the reaction time compared with the no-bite condition. Sol reaction and grounding times showed a negative correlation between clenching strength under moderate conditions and the rate of change in reaction time under no-bite and moderate conditions. Release time exhibited no significant correlation between clenching strength under the moderate condition and the rate of change in reaction time under the no-bite and moderate conditions. The remote facilitation effect of clenching improved the systemic reaction time by producing immediate muscle activity. Conclusions: Clenching shortens the systemic simple reaction time. This finding highlights the potential importance of clenching in enhancing performance during sporting events. Full article
(This article belongs to the Section Kinesiology and Biomechanics)
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18 pages, 1665 KB  
Article
Comprehensive Associations Between Spinal–Pelvic Alignment and Muscle Shortening in Healthy Young Men: An Analysis of Individual and Interactive Effects in the Sagittal Plane Using SHapley Additive exPlanation
by Minami Akao, Yuna Ishikura, Takuma Isshiki, Shinnosuke Tsukada, Hayato Shigetoh and Junya Miyazaki
J. Funct. Morphol. Kinesiol. 2025, 10(3), 259; https://doi.org/10.3390/jfmk10030259 - 9 Jul 2025
Viewed by 651
Abstract
Objectives: To comprehensively examine the association between spinopelvic alignment and muscle shortening in healthy young men, focusing on the individual and interactive effects of thoracic kyphosis, lumbar lordosis, and anterior pelvic tilt using SHapley Additive exPlanation (SHAP) analysis. Methods: Forty-one healthy [...] Read more.
Objectives: To comprehensively examine the association between spinopelvic alignment and muscle shortening in healthy young men, focusing on the individual and interactive effects of thoracic kyphosis, lumbar lordosis, and anterior pelvic tilt using SHapley Additive exPlanation (SHAP) analysis. Methods: Forty-one healthy young adult men participated in this cross-sectional study. Thoracic kyphosis, lumbar lordosis, and anterior pelvic tilt were measured using a flexible curve ruler and inclinometer. Muscle length indices for six muscles (iliopsoas, rectus femoris, gluteus maximus, hamstrings, back extensors, and abdominals) were assessed via standardized physical examinations and image analysis. A machine learning model was developed, and SHAP analysis applied to determine individual and interactive contributions of spinopelvic angles to each muscle length index. Results: SHAP analysis showed that hip-related muscle shortening (iliopsoas, rectus femoris, hamstrings, gluteus maximus) was influenced by both individual alignments and interactions, especially between thoracic kyphosis and lumbar lordosis. Lumbar lordosis was most associated with iliopsoas shortening (SHAP = −0.09), while anterior pelvic tilt was linked to hamstring shortening (SHAP = −0.30). Thoracic kyphosis was the key factor for rectus femoris shortening (SHAP = −0.05). Interactive effects exceeded individual contributions for the rectus femoris, gluteus maximus, and hamstrings. In contrast, spinal alignment had minimal influence on the back extensors and abdominals. Conclusions: Both individual and intersegmental spinal alignments are associated with muscle shortening, particularly in hip-related muscles. The interaction between thoracic kyphosis and lumbar lordosis plays a pivotal role. These findings underscore the importance of evaluating segmental spinal interactions when assessing muscle flexibility and posture. Full article
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13 pages, 624 KB  
Review
Microgravity Therapy as Treatment for Decelerated Aging and Successful Longevity
by Nadine Mozalbat, Lital Sharvit and Gil Atzmon
Int. J. Mol. Sci. 2025, 26(13), 6544; https://doi.org/10.3390/ijms26136544 - 7 Jul 2025
Viewed by 1240
Abstract
Aging is a complex biological process marked by a progressive decline in cellular function, leading to age-related diseases such as neurodegenerative disorders, cancer, and cardiovascular diseases. Despite significant advancements in aging research, finding effective interventions to decelerate aging remains a challenge. This review [...] Read more.
Aging is a complex biological process marked by a progressive decline in cellular function, leading to age-related diseases such as neurodegenerative disorders, cancer, and cardiovascular diseases. Despite significant advancements in aging research, finding effective interventions to decelerate aging remains a challenge. This review explores microgravity as a novel therapeutic approach to combat aging and promote healthy longevity. The hallmarks of aging, including genomic instability, telomere shortening, and cellular senescence, form the basis for understanding the molecular mechanisms behind aging. Interestingly, microgravity has been shown to accelerate aging-like processes in model organisms and human tissues, making it an ideal environment for studying aging mechanisms in an accelerated manner. Spaceflight studies, such as NASA’s Twins Study and experiments aboard the International Space Station (ISS), reveal striking parallels between the physiological changes induced by microgravity and those observed in aging populations, including muscle atrophy, bone density loss, cardiovascular deconditioning, and immune system decline in a microgravity environment. However, upon microgravity recovery, cellular behavior, gene expression, and tissue regeneration were seen, providing vital insights into aging mechanisms and prospective therapeutic approaches. This review examines the potential of microgravity-based technologies to pioneer novel strategies for decelerating aging and enhancing healthspan under natural gravity, paving the way for breakthroughs in longevity therapies. Full article
(This article belongs to the Section Molecular Endocrinology and Metabolism)
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9 pages, 339 KB  
Article
Plyometric Training in Prepubertal Soccer Players: Is It Really Effective for Soccer Performance?
by Edoardo Lo Russo, Matteo Levi Micheli, Andrea Vieri, Pascal Izzicupo and Gabriele Mascherini
Biomechanics 2025, 5(3), 50; https://doi.org/10.3390/biomechanics5030050 - 1 Jul 2025
Viewed by 647
Abstract
Background/Objectives: Plyometric training is a method of increasing soccer performance which leverages the muscle stretch-shortening cycle. This study aimed to evaluate the safety and effectiveness of plyometric training in prepubertal soccer players. Methods: Twenty-three young athletes (age 9.4 ± 0.3 years) from an [...] Read more.
Background/Objectives: Plyometric training is a method of increasing soccer performance which leverages the muscle stretch-shortening cycle. This study aimed to evaluate the safety and effectiveness of plyometric training in prepubertal soccer players. Methods: Twenty-three young athletes (age 9.4 ± 0.3 years) from an elite club, training three times per week, were enrolled. During one of the weekly training sessions, twelve players formed the experimental group (PLYO), incorporating a 45 min plyometric training component into their routine, while the control group (CON), consisting of eleven players continued with their usual training program. At baseline and after 12 weeks, anthropometric parameters, flexibility, lower limb strength, and agility were assessed. Results: At baseline, no differences were observed between the two groups in anthropometric or physical performance parameters. No injuries occurred during the study. After 12 weeks, both groups showed significant growth and performance improvements. However, the PLYO showed a significantly greater increase in lower limb strength (Δ + 10.7%) compared to the CON (Δ + 6.0%). Conversely, although not statistically significant, agility improvements were greater in the CON (Δ + 12.4%) than in the PLYO (Δ + 8.6%). Conclusions: Plyometric training appears to be a safe and effective method for enhancing lower limb strength in prepubertal athletes. However, this strength gain did not directly translate into greater agility, which may benefit more from sport-specific training during this developmental stage. Full article
(This article belongs to the Collection Locomotion Biomechanics and Motor Control)
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27 pages, 7200 KB  
Article
The Biological Consequences of the Knockout of Genes Involved in the Synthesis and Metabolism of H2S in Drosophila melanogaster
by Victoria Y. Shilova, David G. Garbuz, Lyubov N. Chuvakova, Alexander P. Rezvykh, Sergei Y. Funikov, Artem I. Davletshin, Svetlana Y. Sorokina, Ekaterina A. Nikitina, Olga Gorenskaya, Michael B. Evgen’ev and Olga G. Zatsepina
Antioxidants 2025, 14(6), 693; https://doi.org/10.3390/antiox14060693 - 6 Jun 2025
Viewed by 755
Abstract
Here, we describe the effects of double knockout (KO) of the cbs and cse genes, which are responsible for H2S synthesis through the transsulfuration pathway, and KO of the sulfurtransferase gene (dtst1) in Drosophila melanogaster females. The analysis of [...] Read more.
Here, we describe the effects of double knockout (KO) of the cbs and cse genes, which are responsible for H2S synthesis through the transsulfuration pathway, and KO of the sulfurtransferase gene (dtst1) in Drosophila melanogaster females. The analysis of H2S production in flies showed minimal levels in the double- and triple-knockout strains. The double- (cbs-/-; cse-/-) and triple- (cbs-/-; cse-/-; dtst-/-) KO flies exhibited a shortened lifespan and reduced fecundity, and showed dramatic changes in Malpighian tubule morphology. The transcriptomic analysis revealed a profound increase in the expression levels of several genes involved in excretory system function in the double-KO and especially the triple-KO flies. Importantly, major groups of differentially expressed genes (DEGs) in the whole bodies of females and ovaries of KO strains included genes responsible for detoxification, reproduction, mitochondrial activity, excretion, cell migration, and muscle system function. The reduced fecundity observed in the double- and triple-KO flies correlated with pronounced changes in the ovarian transcriptome. At the same time, the single knockout of dtst1 increased the flies’ fecundity and lifespan. Our experiments exploring unique Drosophila strains with KO of major H2S-related genes revealed several new pathways controlled by this ancient adaptogenic system that is involved in various human diseases and aging. Full article
(This article belongs to the Section Antioxidant Enzyme Systems)
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15 pages, 702 KB  
Review
Advances in Molecular Research of Tracheobronchial Tree Aging: A Systematic Review
by Constantin Salahoru, Marius Valeriu Hînganu, Paul Salahoru and Delia Hînganu
Int. J. Mol. Sci. 2025, 26(11), 5128; https://doi.org/10.3390/ijms26115128 - 27 May 2025
Viewed by 651
Abstract
Aging affects all tissues in an organism, including the tracheobronchial tree, with structural and functional changes driven by mechanisms such as oxidative stress, cellular senescence, epigenetic modifications, mitochondrial dysfunction, and telomere shortening. Airway aging can be accelerated by intrinsic or extrinsic factors. This [...] Read more.
Aging affects all tissues in an organism, including the tracheobronchial tree, with structural and functional changes driven by mechanisms such as oxidative stress, cellular senescence, epigenetic modifications, mitochondrial dysfunction, and telomere shortening. Airway aging can be accelerated by intrinsic or extrinsic factors. This review brings together information from the literature on the molecular changes occurring in all layers of the tracheobronchial airway wall. It examines the biomolecular changes associated with aging in the mucosa, submucosa, cartilage, and smooth muscle of the airways. At the mucosal level, aging reduces ciliary function and disrupts mucin homeostasis, impairing mucociliary clearance and contributing to chronic respiratory diseases such as COPD (Chronic Obstructive Pulmonary Disease). Cellular senescence and oxidative stress drive extracellular matrix remodeling and chronic inflammation. Airway cartilage undergoes age-related changes in collagen and fibronectin composition, leading to increased stiffness, while heightened MMP (Matrix Metalloproteinases) activity exacerbates ECM (extracellular matrix) degradation. In airway smooth muscle, aging induces changes in calcium signaling, hypertrophy, and the secretion of pro-inflammatory mediators, further perpetuating airway remodeling. These changes impair respiratory function and increase susceptibility to chronic respiratory conditions in the elderly. By consolidating current knowledge, this review aims to provide a comprehensive overview of the molecular changes occurring in the respiratory tract with aging and to highlight new molecular perspectives for future research on this topic. Full article
(This article belongs to the Section Biochemistry)
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10 pages, 578 KB  
Article
Inspiratory Muscle Training Improved Cardiorespiratory Performance in Patients Undergoing Open Heart Surgery: A Randomized Controlled Trial
by Chitima Kulchanarat, Suphannee Choeirod, Supattra Thadatheerapat, Dusarkorn Piathip, Opas Satdhabudha and Kornanong Yuenyongchaiwat
Adv. Respir. Med. 2025, 93(3), 10; https://doi.org/10.3390/arm93030010 - 27 May 2025
Viewed by 1261
Abstract
Aim: This study aimed to evaluate the effects of inspiratory muscle training on inspiratory muscle strength and cardiorespiratory performance in patients undergoing open heart surgery. Method: This study was conducted as a randomized controlled trial with two groups. Fifty-eight patients who underwent open [...] Read more.
Aim: This study aimed to evaluate the effects of inspiratory muscle training on inspiratory muscle strength and cardiorespiratory performance in patients undergoing open heart surgery. Method: This study was conducted as a randomized controlled trial with two groups. Fifty-eight patients who underwent open heart surgery were randomly assigned to either the intervention group or the control group 29 in the control group and 29 in the intervention group. Patients in the intervention group participated in a physical therapy program combined with inspiratory muscle training using the Thammasat University (TU) Breath Trainer. Patients in the control group received only the standard physical therapy program. The maximum inspiratory pressure, maximum expiratory pressure and 6 min walk test distance were assessed both before surgery and prior to hospital discharge. Results: The intervention group had a significant increase in maximum inspiratory pressure (p < 0.001), maximum expiratory pressure (p < 0.001) and 6 min walk test distance (p = 0.013). The control group had a significant decrease in maximum inspiratory pressure (p < 0.001), maximum expiratory pressure (p = 0.002) and 6 min walk test distance (p < 0.001). Conclusions: Inspiratory muscle training can be performed using maximum pressure resistors, such as the TU-Breath Trainer device. This training has been shown to effectively improve inspiratory muscle strength and cardiorespiratory performance in patients undergoing open heart surgery, as well as reduce pulmonary complications and shorten the length of hospital stay. Full article
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18 pages, 12199 KB  
Article
Impairment of Muscle Function Causes Pupal Lethality in Flies Expressing the Mitochondrial Alternative Oxidase
by Carlos A. Couto-Lima, Sina Saari, Geovana S. Garcia, Gabriel H. Rocha, Johanna ten Hoeve, Eric Dufour and Marcos T. Oliveira
Biomolecules 2025, 15(4), 570; https://doi.org/10.3390/biom15040570 - 11 Apr 2025
Viewed by 699
Abstract
The mitochondrial alternative oxidase (AOX) from the tunicate Ciona intestinalis has been explored as a potential therapeutic enzyme for human mitochondrial diseases, yet its systemic effects remain poorly understood. Here, we investigate the metabolic and physiological consequences of AOX expression during the development [...] Read more.
The mitochondrial alternative oxidase (AOX) from the tunicate Ciona intestinalis has been explored as a potential therapeutic enzyme for human mitochondrial diseases, yet its systemic effects remain poorly understood. Here, we investigate the metabolic and physiological consequences of AOX expression during the development of Drosophila cultured under dietary stress. We show that the combination of strong, ubiquitous AOX expression and a low-nutrient condition leads to pupal lethality and severe defects in larval musculature, characterized by actin aggregation and muscle shortening. These structural abnormalities correlate with a decrease in larval biomass and motility. Interestingly, the muscle defects and the motility impairments vary in severity among individuals, predicting survival rates at the pupal stage. AOX expression in specific tissues (muscle, nervous system or fat body) does not individually recapitulate the lethal phenotype observed with ubiquitous expressions of the enzyme, indicating a complex metabolic imbalance. Metabolomic analysis revealed that the low-nutrient diet and AOX expression have opposite effects on most metabolites analyzed, especially in the levels of amino acids. Notably, supplementation of the low-nutrient diet with the essential amino acids methionine and/or tryptophan partially rescues pupal viability, body size, muscle morphology, and locomotion, whereas supplementation with proline and/or glutamate does not, highlighting a specific perturbation in amino acid metabolism rather than general bioenergetic depletion. These findings demonstrate that AOX expression disrupts metabolic homeostasis, with developmental and physiological consequences that must be considered when evaluating AOX for therapeutic applications. Full article
(This article belongs to the Special Issue Drosophila as a Model System to Study Metabolism)
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17 pages, 2384 KB  
Article
The Contractile Function of Ventricular Cardiomyocytes Is More Sensitive to Acute 17β-Estradiol Treatment Compared to Atrial Cardiomyocytes
by Tatiana A. Myachina, Xenia A. Butova, Raisa A. Simonova, Denis A. Volzhaninov, Anastasia M. Kochurova, Galina V. Kopylova, Daniil V. Shchepkin and Anastasia D. Khokhlova
Cells 2025, 14(8), 561; https://doi.org/10.3390/cells14080561 - 8 Apr 2025
Viewed by 672
Abstract
17β-estradiol (E2) is the most active metabolite of estrogen with a wide range of physiological action on cardiac muscle. Previous studies have reported E2 effects predominantly for the ventricles, while the E2 impact on the atria has been less examined. In this study, [...] Read more.
17β-estradiol (E2) is the most active metabolite of estrogen with a wide range of physiological action on cardiac muscle. Previous studies have reported E2 effects predominantly for the ventricles, while the E2 impact on the atria has been less examined. In this study, we focused on the direct E2 effects on atrial and ventricular contractility at the cellular and molecular levels. Single atrial and ventricular cardiomyocytes (CM) from adult (24 weeks-old) female Wistar rats were incubated with 10 nM E2 for 15 min. Sarcomere length and cytosolic [Ca2+]i transients were measured in mechanically non-loaded CM, and the tension–length relationship was studied in CM mechanically loaded by carbon fibers. The actin–myosin interaction and sarcomeric protein phosphorylation were analyzed using an in vitro motility assay and gel electrophoresis with Pro-Q Diamond phosphoprotein stain. E2 had chamber-specific effects on the contractile function of CM with a pronounced influence on ventricular CM. The characteristics of [Ca2+]i transients did not change in both atrial and ventricular CM. However, in ventricular CM, E2 reduced the amplitude and maximum velocity of sarcomere shortening and decreased the slope of the passive tension–length relationship that was associated with increased TnI and cMyBP-C phosphorylation. E2 treatment accelerated the cross-bridge cycle of both atrial and ventricular myosin that was associated with increased phosphorylation of the myosin essential light chain. This study shows that E2 impairs the mechanical function of the ventricular myocardium while atrial contractility remains mostly preserved. Hormonal replacement therapy (HRT) with estrogen is by far the most effective therapy for treating climacteric symptoms experienced during menopause. Here we found a chamber specificity of myocardial contractile function to E2 that should be taken into account for the potential side effects of HRT. Full article
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20 pages, 1816 KB  
Case Report
The Influence of Step Load Periodisation Based on Time Under Tension in Hypoxic Conditions on Hormone Concentrations and Postoperative ACL Rehabilitation of a Judo Athlete: A Case Study
by Miłosz Drozd, Wojciech Luboń, Jose Antonio Perez Turpin and Wojciech Grzyb
J. Clin. Med. 2025, 14(8), 2549; https://doi.org/10.3390/jcm14082549 - 8 Apr 2025
Viewed by 767
Abstract
The aim of this study was to determine the effect of a step load periodisation protocol for the rehabilitation of the anterior cruciate ligament (ACL) based on the variables of both the tempo of movement and time under tension (TUT) in normobaric hypoxia [...] Read more.
The aim of this study was to determine the effect of a step load periodisation protocol for the rehabilitation of the anterior cruciate ligament (ACL) based on the variables of both the tempo of movement and time under tension (TUT) in normobaric hypoxia using a case study. Introduction: We verified the influence of variables such as time under tension (TUT) and the tempo of movement in hypoxia on the concentration of insulin-like growth factor 1 (IGF-1), growth hormone (GH), and erythropoietin (EPO). The effectiveness of the protocol also concerned variables such as peak torque of the knee flexors and extensors and maximum oxygen uptake (VO2max), as well as body composition analysis. Methods: The study used a 28-year-old judoka athlete from the national team, competing in the weight category up to 73 kg. Results: The use of short partial rest breaks between series (80s) in combination with six exercises in four series and a hypoxic environment (FiO2 = 15%) significantly increased metabolic stress, resulting in the highest increase in GH and IGF in the main phase of accumulation of the 3:1 step load. During 16 running sessions, the rehabilitated athlete achieved a significant increase in individual variables in the running test. Conclusions: The combination of a hypoxic environment combined with a periodized rehabilitation protocol can induce a number of positive hormonal, circulatory and respiratory reactions as well as positively influence muscle asymmetry, which can ultimately shorten the time it takes for an athlete to return to sport (RTS). Full article
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23 pages, 276 KB  
Article
Effects of Reduced Amino Acids and Apparent Metabolizable Energy on Meat Processing, Internal Organ Development, and Economic Returns of Cobb 700 and Ross 708 Broilers
by Bo Zhang, Shengyu Zhou, Wei Zhai and Yang Zhao
Animals 2025, 15(7), 1064; https://doi.org/10.3390/ani15071064 - 6 Apr 2025
Viewed by 517
Abstract
The rapid growth and high nutrient density in modern broiler production have led to issues like woody breast myopathy (WBM), footpad dermatitis, and fat accumulation, affecting welfare and profitability. This study evaluated the effects of amino acid (AA) and apparent metabolizable energy (AME) [...] Read more.
The rapid growth and high nutrient density in modern broiler production have led to issues like woody breast myopathy (WBM), footpad dermatitis, and fat accumulation, affecting welfare and profitability. This study evaluated the effects of amino acid (AA) and apparent metabolizable energy (AME) reductions on organ development, carcass yield, WBM incidence, and economic returns in Cobb 700 and Ross 708 broilers. Two trials were conducted, one per strain, using a factorial design with 12 treatments (four AA × three AME). Each trial included 864 broilers, randomly assigned to six replicate blocks, with 12 pens per block (six males and six females per pen). Diets contained 70%, 80%, 90%, or 100% of digestible AA and 84%, 92%, or 100% AME based on breeder recommendations. A 30% AA reduction increased fat pad weight, promoted proventriculus and jejunum development (day 58), reduced carcass and tenderloin weights, lowered moderate/severe WBM incidence (day 47), and shortened footpad dermatitis. A 16% AME reduction decreased fat pad weight, improved muscle production and returns, but reduced normal breast percentage (days 40 and 47). The recommended protein–energy ratio (g/MJ) for optimal economic returns was as follows: 19.78 (0–10 d), 17.51 (11–24 d), 16.03 (25–39 d), and 15.25 (40–63 d). Full article
(This article belongs to the Special Issue Amino Acid Nutrition in Poultry: 2nd Edition)
13 pages, 508 KB  
Article
Morphofunctional Characteristics of the Foot and Ankle in Competitive Swimmers and Their Association with Muscle Pain
by Cristina Jiménez-Braganza, Antonia Sáez-Díaz and Pedro Vicente Munuera-Martínez
Appl. Sci. 2025, 15(7), 3755; https://doi.org/10.3390/app15073755 - 29 Mar 2025
Viewed by 548
Abstract
The aim of this study was to analyze the joint characteristics of the foot and ankle in competitive swimmers aged 16–18 and 19–24 years and their relationship with the presence of muscle pain during swimming. A total of 74 swimmers were evaluated: 38 [...] Read more.
The aim of this study was to analyze the joint characteristics of the foot and ankle in competitive swimmers aged 16–18 and 19–24 years and their relationship with the presence of muscle pain during swimming. A total of 74 swimmers were evaluated: 38 ‘junior’ (16–18 years) and 36 ‘senior’ (19–24 years). The following parameters were recorded: ankle dorsiflexion, rearfoot mobility, first metatarsophalangeal dorsiflexion, presence of hallux valgus, foot posture, first ray mobility, arch height, and plantar pressure. Additionally, the frequency and location of muscle pain in the triceps surae were analyzed. A cluster analysis was performed to identify variables that differentiated both groups. Ankle dorsiflexion was limited in both groups, with a greater restriction observed in adults (p < 0.001 with an extended knee; p < 0.014 with a flexed knee). The predominant foot type was the cavus foot. The most common pain was localized in the triceps surae, followed by the plantar musculature, with no significant differences between groups. Swimmers exhibited gastrocnemius shortening, which could limit ankle dorsiflexion and contribute to the onset of muscle pain in the leg and foot. These findings suggest the importance of incorporating lower limb flexibility strategies into the training of competitive swimmers. Full article
(This article belongs to the Special Issue Advanced Research in Foot and Ankle Kinematics)
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