Browsing by Subject "Myostatin"

Now showing 1 - 3 of 3
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    Bone is Not Alone: the Effects of Skeletal Muscle Dysfunction in Chronic Kidney Disease
    (Springer, 2015-06) Avin, Keith G.; Moorthi, Ranjani N.; Department of Health Sciences, School of Health and Rehabilitation Sciences
    Chronic kidney disease (CKD) is associated with a decline in muscle mass, strength, and function, collectively called "sarcopenia." Sarcopenia is associated with hospitalizations and mortality in CKD and is therefore important to understand and characterize. While the focus of skeletal health in CKD has traditionally focused on bone and mineral aberrations, it is now recognized that sarcopenia must also play a role in poor musculoskeletal health in this population. In this paper, we present an overview of skeletal muscle changes in CKD, including defects in skeletal muscle catabolism and anabolism in uremic tissue. There are many gaps in knowledge in this field that should be the focus for future research to unravel pathogenesis and therapies for musculoskeletal health in CKD.
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    Myostatin inhibits osteoblastic differentiation by suppressing osteocyte-derived exosomal microRNA-218: A novel mechanism in muscle-bone communication
    (American Society for Biochemistry and Molecular Biology, 2017-06-30) Qin, Yiwen; Peng, Yuanzhen; Zhao, Wei; Pan, Jianping; Ksiezak-Reding, Hanna; Cardozo, Christopher; Wu, Yingjie; Divieti Pajevic, Paola; Bonewald, Lynda F.; Bauman, William A.; Qin, Weiping; Medicine, School of Medicine
    Muscle and bone are closely associated in both anatomy and function, but the mechanisms that coordinate their synergistic action remain poorly defined. Myostatin, a myokine secreted by muscles, has been shown to inhibit muscle growth, and the disruption of the myostatin gene has been reported to cause muscle hypertrophy and increase bone mass. Extracellular vesicle-exosomes that carry microRNA (miRNA), mRNA, and proteins are known to perform an important role in cell-cell communication. We hypothesized that myostatin may play a crucial role in muscle-bone interactions and may promote direct effects on osteocytes and on osteocyte-derived exosomal miRNAs, thereby indirectly influencing the function of other bone cells. We report herein that myostatin promotes expression of several bone regulators such as sclerostin (SOST), DKK1, and RANKL in cultured osteocytic (Ocy454) cells, concomitant with the suppression of miR-218 in both parent Ocy454 cells and derived exosomes. Exosomes produced by Ocy454 cells that had been pretreated with myostatin could be taken up by osteoblastic MC3T3 cells, resulting in a marked reduction of Runx2, a key regulator of osteoblastic differentiation, and in decreased osteoblastic differentiation via the down-regulation of the Wnt signaling pathway. Importantly, the inhibitory effect of myostatin-modified osteocytic exosomes on osteoblast differentiation is completely reversed by expression of exogenous miR-218, through a mechanism involving miR-218-mediated inhibition of SOST. Together, our findings indicate that myostatin directly influences osteocyte function and thereby inhibits osteoblastic differentiation, at least in part, through the suppression of osteocyte-derived exosomal miR-218, suggesting a novel mechanism in muscle-bone communication.
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    Targeting the Activin Receptor Signaling to Counteract the Multi-Systemic Complications of Cancer and Its Treatments
    (MDPI, 2021-02-28) Hulmi, Juha J.; Nissinen, Tuuli A.; Penna, Fabio; Bonetto, Andrea; Surgery, School of Medicine
    Muscle wasting, i.e., cachexia, frequently occurs in cancer and associates with poor prognosis and increased morbidity and mortality. Anticancer treatments have also been shown to contribute to sustainment or exacerbation of cachexia, thus affecting quality of life and overall survival in cancer patients. Pre-clinical studies have shown that blocking activin receptor type 2 (ACVR2) or its ligands and their downstream signaling can preserve muscle mass in rodents bearing experimental cancers, as well as in chemotherapy-treated animals. In tumor-bearing mice, the prevention of skeletal and respiratory muscle wasting was also associated with improved survival. However, the definitive proof that improved survival directly results from muscle preservation following blockade of ACVR2 signaling is still lacking, especially considering that concurrent beneficial effects in organs other than skeletal muscle have also been described in the presence of cancer or following chemotherapy treatments paired with counteraction of ACVR2 signaling. Hence, here, we aim to provide an up-to-date literature review on the multifaceted anti-cachectic effects of ACVR2 blockade in preclinical models of cancer, as well as in combination with anticancer treatments.