Review
Cell Biology
Michaela E. Trautman, Nicole E. Richardson, Dudley W. Lamming
Summary: The proportion of people suffering from age-related diseases is increasing worldwide. Recent research has shown that low protein diets, particularly those low in branched-chain amino acids (BCAAs), can reduce mortality and promote metabolic health and extended lifespan in both humans and rodents. This article discusses the emerging evidence that BCAAs play a crucial role in healthy metabolism and longevity, and explores the physiological and molecular mechanisms behind the benefits of restricting dietary BCAAs. The findings suggest that the quality of protein, specifically the composition of dietary protein, may be a previously overlooked factor in metabolic dysfunction and reducing dietary BCAAs could be a promising new approach to delaying and preventing age-related diseases.
Article
Pharmacology & Pharmacy
Tiangang Wu, Mengling Wang, Fengling Ning, Shilin Zhou, Xuetao Hu, Hong Xin, Svetlana Reilly, Xuemei Zhang
Summary: Fibrosis, characterized by excessive production of extracellular matrix, is a common pathological feature of organ diseases. Metabolic alterations, especially in the regulation of branched-chain amino acids (BCAAs), have been found to play significant roles in fibrogenesis. Dysregulation of BCAAs metabolism has been implicated in various diseases. This review summarizes the metabolic regulation of fibrosis, changes in BCAAs metabolism associated with fibrosis, and the effects and mechanisms of BCAAs intervention in hepatic, renal, and cardiac fibrosis, with a focus on liver fibrosis and associated hepatocellular carcinoma.
PHARMACOLOGICAL RESEARCH
(2023)
Article
Nutrition & Dietetics
Klara J. Lohkamp, Anita M. van den Hoek, Gemma Sole-Guardia, Maria Lisovets, Talissa Alves Hoffmann, Konstantina Velanaki, Bram Geenen, Vivienne Verweij, Martine C. Morrison, Robert Kleemann, Maximilian Wiesmann, Amanda J. Kiliaan
Summary: Exercise and dietary interventions are effective approaches to combat obesity and its impact on the brain. The study found that exercise alone can improve cerebral blood flow, reduce white matter loss, and decrease neuroinflammation. However, when combined with BCAA supplementation, neuroinflammation was increased. Nevertheless, the combination of BCAA and exercise showed beneficial effects on metabolism, behavior, and cognition.
Review
Genetics & Heredity
Can Chen, Hassan Naveed, Keping Chen
Summary: This article introduces the important role of branched-chain amino acid aminotransferases in cellular metabolism, summarizes the related research in animals, plants, microorganisms, and humans, and analyzes the molecular mechanism. It has been found that disorders in branched-chain amino acid metabolism are closely related to various diseases, especially tumor development.
FRONTIERS IN GENETICS
(2023)
Article
Nutrition & Dietetics
Katarzyna Paczkowska, Dominik Rachon, Andrzej Berg, Jacek Rybka, Katarzyna Kapczynska, Marek Bolanowski, Jacek Daroszewski
Summary: Polycystic ovary syndrome (PCOS) is a common endocrine disorder that predisposes women to metabolic disturbances. Recent research suggests that alterations in amino acid profiles may be indicative of metabolic disorders. This study found elevated levels of aromatic amino acids in PCOS women, and significant differences in amino acid concentrations between metabolically healthy and unhealthy obesity subgroups of PCOS women.
Review
Physiology
Gagandeep Mann, Stephen Mora, Glory Madu, Olasunkanmi A. J. Adegoke
Summary: BCAAs are crucial for skeletal muscle and whole-body anabolism and energy balance, but elevated levels and impaired metabolism may lead to chronic diseases like insulin resistance. Research is focusing on mechanisms regulating BCAA metabolism and its impact on muscle and whole-body metabolism.
FRONTIERS IN PHYSIOLOGY
(2021)
Article
Nutrition & Dietetics
Huan Xu, Xuanyang Wang, Xiaoqing Xu, Lin Liu, Yuntao Zhang, Xuemin Yan, Yingfeng Zhang, Keke Dang, Ying Li
Summary: This study using Mendelian randomization analysis found that increased circulating levels of BCAAs were associated with an increased risk of squamous cell lung cancer, but no causal link was found between BCAAs and other types of cancer.
CLINICAL NUTRITION
(2023)
Article
Biochemistry & Molecular Biology
Mai Wajiki, Takayuki Yamamoto, Hiroko Maruki-Uchida, Hirotaka Nagashima, Tetsu Shimizu, Minoru Morita
Summary: Co-ingestion of whey protein and sucrose suppresses blood glucose levels and increases insulin levels, but does not affect amino acid absorption of whey protein.
Article
Agriculture, Multidisciplinary
Lingyu Zhang, Fengna Li, Qiuping Guo, Yehui Duan, Wenlong Wang, Yuhuan Yang, Yunju Yin, Saiming Gong, Mengmeng Han, Yulong Yin
Summary: The supplementation of BCAAs (leucine/isoleucine/valine = 2:1:1 or 2:1:2) in protein-restricted diets can improve growth performance and carcass characteristics in finishing pigs. It also modulates lipid metabolism by accelerating the secretion of adipokines and fatty acid oxidation.
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
(2021)
Article
Nutrition & Dietetics
Mohamad Tarik, Lakshmy Ramakrishnan, Nidhi Bhatia, Ravindra Goswami, Devasenathipathy Kandasamy, Atanu Roy, Dinu S. Chandran, Archna Singh, Ashish Datt Upadhyay, Mani Kalaivani, Jayanthi Neelamraju, Ratna Sudha Madempudi, Reena Rajan
Summary: The effect of Bacillus coagulans Unique IS-2 supplementation on protein absorption and utilization in resistance-trained males was assessed in this study. The results showed that Bacillus coagulans Unique IS-2 supplementation significantly increased protein absorption and intake of branched chain amino acids (BCAA), while also improving lower body muscle strength.
EUROPEAN JOURNAL OF NUTRITION
(2022)
Article
Nutrition & Dietetics
Yuyan Liu, Chengwen Zhang, Yuan Zhang, Xuheng Jiang, Yuanhong Liang, Huan Wang, Yongfang Li, Guifan Sun
Summary: This study aimed to investigate the relationship between dietary intake of branched-chain amino acids (BCAAs) and hypertension risk in the Chinese population. The findings showed that dietary BCAAs intake was positively associated with both systolic and diastolic blood pressure values, as well as an increased risk of hypertension.
Review
Immunology
Berkay Yahsi, Gurcan Gunaydin
Summary: Immunometabolism, especially in terms of augmenting anti-tumor immune responses, has been extensively researched. Regulatory T cells (Tregs) are known for their immunosuppressive roles in anti-tumor immune responses. Targeting Tregs specifically in the tumor microenvironment (TME) is crucial for successful and specific treatment. Recent studies have shown an association between Tregs and isoleucine, which may play a major role in affecting Tregs. Targeting the immunometabolic pathways of Tregs could be a rational approach for treatment.
FRONTIERS IN IMMUNOLOGY
(2022)
Article
Physiology
Yunfeng Dong, Xuejiao Zhang, Rui Miao, Wei Cao, Hao Wei, Wei Jiang, Ruirui Gao, Yanhui Yang, Haipeng Sun, Junqiang Qiu
Summary: This study found that branched-chain amino acids (BCAAs) promote the repair of exercise-induced muscle damage (EIMD) by regulating the polarization state of macrophages. BCAAs enhance M1 polarization through the mTORC1-HIF1 alpha-glycolysis pathway and promote M2 polarization independently of mTORC1. Furthermore, BCAAs stimulate the proliferation of M1 macrophages and the differentiation of M2 macrophages.
FRONTIERS IN PHYSIOLOGY
(2022)
Article
Engineering, Chemical
Maiara Giroldi, Isabel Marie Grambusch, Daniel Neutzling Lehn, Claucia Fernanda Volken de Souza
Summary: The acceptance of dairy protein hydrolysates can be affected by characteristics like bitter taste and physiochemical instability, but encapsulation methods can minimize these challenges. Among various encapsulation methods, spray drying shows better results in maintaining bioactivity while being cost-effective. Polysaccharides as encapsulating agents are highlighted for their superior performance in protecting bioactive compounds.
Review
Biochemistry & Molecular Biology
Paola Cuomo, Rosanna Capparelli, Antonio Iannelli, Domenico Iannelli
Summary: Branched-chain amino acids (BCAAs) play an important role in human health. High levels of BCAAs are associated with various metabolic diseases, while low levels are beneficial for metabolic health. However, the exact mechanisms underlying the dysregulation caused by high levels of BCAAs are still under debate.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2022)
Article
Multidisciplinary Sciences
Anders Karlsen, Alba Gonzalez-Franquesa, Jens R. Jakobsen, Michael R. Krogsgaard, Manuel Koch, Michael Kjaer, Stefano Schiaffino, Abigail L. Mackey, Atul S. Deshmukh
Summary: Proteomics analysis of skeletal muscle has advanced to single myofibers and specifically focused on the myotendinous junction (MTJ). By progressively removing muscle components, researchers identified 112 significantly enriched MTJ proteins, including 24 known proteins and 88 novel markers. This study provides the first detailed MTJ proteomics resource for understanding the biology and pathologies of the MTJ.
Article
Cell Biology
Casper Soendenbroe, Mette F. Heisterberg, Peter Schjerling, Michael Kjaer, Jesper L. Andersen, Abigail L. Mackey
Summary: Heavy resistance exercise has the potential to modify denervation indices in healthy elderly individuals, as evidenced by decreases in gene expression levels of AChR a1 and a. subunits, supporting the stability of the neuromuscular junction. However, longer timeframes may be needed for protein-level adaptations to manifest.
AMERICAN JOURNAL OF PHYSIOLOGY-CELL PHYSIOLOGY
(2022)
Article
Cell Biology
Jens R. Jakobsen, Peter Schjerling, Michael Kjaer, Abigail L. Mackey, Michael R. Krogsgaard
Summary: This study found that a single bout of eccentric exercise had an effect on the expression of NES and OSTN mRNA in the myotendinous junction (MTJ) and tendon fractions. Genes previously identified at the MTJ were expressed at a higher level compared to muscle and tendon but were unaffected by exercise. Additionally, the exercise group showed a higher concentration of macrophages in muscle close to the MTJ. These results suggest that NES and OSTN may play a role in explaining how the MTJ adapts to eccentric exercise.
HISTOCHEMISTRY AND CELL BIOLOGY
(2022)
Article
Biochemistry & Molecular Biology
Tingting Gu, Jesper Just, Katrine Tang Stenz, Yan Yan, Peter Sieljacks, Jakob Wang, Thomas Skjaerlund Groennebaek, Jesper Emil Jakobsgaard, Emil Rindom, Jon Herskind, Anders Gravholt, Thomas Ravn Lassen, Mathias Jorgensen, Rikke Baek, Eugenio Gutierrez-Jimenez, Nina Kerting Iversen, Peter Mondrup Rasmussen, Jens Randel Nyengaard, Malene Moller Jorgensen, Frank de Paoli, Hans Erik Botker, Jorgen Kjems, Kristian Vissing, Kim Ryun Drasbek
Summary: Ischemic conditioning and exercise can protect against brain ischemia-reperfusion injury by inducing the release of circulating EVs. However, further experimental verification is needed for the in vivo and translational effects of conditioned EVs.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2022)
Article
Sport Sciences
Jens Rithamer Jakobsen, Abigail Louise Mackey, Manuel Koch, Thomas Imhof, Jens Hannibal, Michael Kjaer, Michael Rindom Krogsgaard
Summary: The myotendinous junction (MTJ) is structurally specialized to transmit force. Muscles with a high content of type II muscle fibers are more prone to strain injury compared to those with type I muscle fibers. Confocal microscopy analysis revealed that the surface area of the MTJ is smaller in type II muscle fibers compared to type I fibers. This suggests that type II muscle fibers have lower resistance to strain and are therefore more susceptible to injury.
SCANDINAVIAN JOURNAL OF MEDICINE & SCIENCE IN SPORTS
(2023)
Article
Cell Biology
Mark R. Viggars, Daniel J. Owens, Claire Stewart, Catherine Coirault, Abigail L. Mackey, Jonathan C. Jarvis
Summary: PCM1 is detected in single isolated myofibers and cross sections from mice and humans, playing an important role in the subcellular location of myonuclei. It is found in the nuclear envelope of mature myofibers and newly formed myotubes, as well as in the centrosomes of proliferating myogenic precursors. Although not completely specific to myonuclei, PCM1 may be useful as a marker of satellite cell dynamics.
AMERICAN JOURNAL OF PHYSIOLOGY-CELL PHYSIOLOGY
(2023)
Article
Physiology
Jakob Wang, Anna-Maria Godsk Mogensen, Frederik Thybo, Magnus Brandbyge, Jonas Brorson, Gerrit van Hall, Jakob Agergaard, Frank Vincenzo de Paoli, Benjamin F. Miller, Hans Erik Botker, Jean Farup, Kristian Vissing
Summary: This study found that low-load blood flow-restricted resistance exercise (BFRRE) is effective in promoting muscle hypertrophy and improving muscle function in older individuals. However, its impact on age-related skeletal muscle decay at a cellular level is still unclear. BFRRE resulted in significant increases in muscle fiber morphology, integrated muscle protein synthesis, and muscle functional capacity without changes in muscle stem cells (MuSCs) and myonuclear content.
JOURNAL OF APPLIED PHYSIOLOGY
(2023)
Article
Cell Biology
Anders Karlsen, Ching-Yan Chloe Yeung, Peter Schjerling, Linda Denz, Christian Hoegsbjerg, Jens R. Jakobsen, Michael R. Krogsgaard, Manuel Koch, Stefano Schiaffino, Michael Kjaer, Abigail L. Mackey
Summary: Through single-nucleus RNA sequencing, we identified distinct clusters of myonuclei in the myotendinous junction (MTJ) of humans, characterized by different gene expression profiles and fiber types, which has important implications for understanding the specialization of the MTJ.
JOURNAL OF CELL SCIENCE
(2023)
Article
Cell Biology
Jakob Wang, Emil Rindom, Thomas Groennebaek, Peter Sieljacks, Jesper Emil Jakobsgaard, Jean Farup, Kristian Vissing, Thomas Holm Pedersen, Frank Vincenzo de Paoli
Summary: The contractile function of skeletal muscle depends on the ability of muscle fibers to generate and transmit action potentials. This study investigated the effects of high-load resistance exercise and low-load blood flow restricted resistance exercise on ClC-1 and NKA subunit isoform expression.
JOURNAL OF MUSCLE RESEARCH AND CELL MOTILITY
(2023)
Review
Physiology
Michael D. Roberts, John J. McCarthy, Troy A. Hornberger, Stuart M. Phillips, Abigail L. Mackey, Gustavo A. Nader, Marni D. Boppart, Andreas N. Kavazis, Paul T. Reidy, Riki Ogasawara, Cleiton A. Libardi, Carlos Ugrinowitsch, Frank W. Booth, Karyn A. Esser
Summary: Mechanisms underlying mechanical overload-induced muscle hypertrophy have been extensively researched. Most studies support the involvement of enhanced mTORC1 signaling, expansion of translational capacity, increased satellite cell abundance and myonuclear accretion, and increased muscle protein synthesis rates. However, additional mechanisms may also be involved.
PHYSIOLOGICAL REVIEWS
(2023)
Article
Cell Biology
Grith Hojfeldt, Trent Sorenson, Alana Gonzales, Michael Kjaer, Jesper L. Andersen, Abigail L. Mackey
Summary: This study aimed to systematically investigate myofibre branching and fibre type in human skeletal muscle undergoing adult regenerative myogenesis. The findings suggest that myofibre branching is more likely to be fusion of myotubes, explained by incomplete regeneration after necrosis-inducing event.
Article
Geriatrics & Gerontology
Casper Soendenbroe, Anders Karlsen, Rene B. Svensson, Michael Kjaer, Jesper L. Andersen, Abigail L. Mackey
Summary: This study reveals the relationship between myofiber shape and age in humans and suggests that it independently predicts volumetric and functional assessments of muscle health. Resistance training can modify the shape of myofibers.
JOURNAL OF CACHEXIA SARCOPENIA AND MUSCLE
(2023)
Review
Sport Sciences
Mikkel Oxfeldt, Line Barner Dalgaard, Jean Farup, Mette Hansen
Summary: In recent years, there has been increasing interest in female physiology, especially regarding the variations of female sex hormones during the menstrual cycle and menopausal transition, as well as the influence of hormonal contraception and therapy on skeletal muscle tissue. While macro outcomes have been extensively studied, there has been relatively less focus on the underlying mechanisms of how sex hormones regulate skeletal muscle tissue. Animal studies have shown a strong relationship between estrogen and satellite cells (SCs), which are muscle stem cells involved in skeletal muscle regulation. Recently, a few human studies have been published to investigate this relationship. This study aims to provide an updated review on female sex hormones and their role in SC regulation, including the influence of estrogen deficiency, supplementation, menopause, hormone therapy, hormonal contraceptives, and the menstrual cycle on SCs in both animal and human trials.
TRANSLATIONAL SPORTS MEDICINE
(2022)
Meeting Abstract
Orthopedics
J. Bjerre-Bastos, C. Sejersen, H. B. Nielsen, N. H. Secher, C. -C. Kitchen, C. P. Miller, A. L. Mackey, A. R. Bihlet
OSTEOARTHRITIS AND CARTILAGE
(2022)
Meeting Abstract
Orthopedics
J. J. Bjerre-Bastos, C. Sejersen, H. B. Nielsen, M. Boesen, N. H. Secher, G. Distajo, V. Flood, Y. Henrotin, M. Uebelhoer, A. Mackey, P. Krustrup, C. -C. Kitchen, E. E. Petersen, C. S. Thudium, J. R. Andersen, A. R. Bihlet
OSTEOARTHRITIS AND CARTILAGE
(2022)