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Lupi SM, Sassi AN, Addis A, Rodriguez y Baena R. The Impact of Nandrolone Decanoate in the Osseointegration of Dental Implants in a Rabbit Model: Histological and Micro-Radiographic Results. MATERIALS 2021; 14:ma14092258. [PMID: 33925604 PMCID: PMC8123797 DOI: 10.3390/ma14092258] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Revised: 04/22/2021] [Accepted: 04/24/2021] [Indexed: 11/23/2022]
Abstract
Despite high rates of osseointegration in healthy patients, complex cases present an increased risk of osseointegration failure when treated with dental implants. Furthermore, if immediate loading of the implants is used, maximizing the response of the host organism would be desirable. Anabolic steroids, such as Nandrolone Decanoate (ND), are reported to have beneficial clinical effects on various bone issues such as osteoporosis and bone fractures. However, their beneficial effects in promoting osseointegration in dental implant placement have not been documented. The study aimed to examine histological changes induced by ND in experimental dental implants in rabbit models. Two dental implants were placed in the tibias of 24 adult rabbits. Rabbits were allocated to one of two groups: control group or test group. Rabbits in the latter group were given nandrolone decanoate (15 mg/kg, immediately after implant placement and after 1 week). Micro-radiographic and histological analyses were assessed to characterize the morphological changes promoted by the nandrolone decanoate use. Total bone volume and fluorescence were significantly higher in the control group after 2 weeks. Such a difference between the two groups might indicate that, initially, nandrolone lengthens the non-specific healing period characteristic of all bone surgeries. However, after the beginning of the reparative processes, the quantity of newly formed bone appears to be significantly higher, indicating a positive stimulation of the androgen molecule on bone metabolism. Based on micro-radiology and fluorescence microscopy, nandrolone decanoate influenced bone regeneration in the implant site. The anabolic steroid nandrolone decanoate affects the healing processes of the peri-implant bone and therefore has the potential to improve the outcomes of implant treatment in medically complex patients.
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Affiliation(s)
- Saturnino Marco Lupi
- Department of Clinical Surgical, Diagnostic and Pediatric Sciences, University of Pavia, 27100 Pavia, Italy; (A.N.S.); (R.R.y.B.)
- Correspondence:
| | - Alessandra Nicole Sassi
- Department of Clinical Surgical, Diagnostic and Pediatric Sciences, University of Pavia, 27100 Pavia, Italy; (A.N.S.); (R.R.y.B.)
| | - Alessandro Addis
- CRABCC, Biotechnology Research Centre for Cardiothoracic Applications, 26027 Rivolta d’Adda, Italy;
| | - Ruggero Rodriguez y Baena
- Department of Clinical Surgical, Diagnostic and Pediatric Sciences, University of Pavia, 27100 Pavia, Italy; (A.N.S.); (R.R.y.B.)
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Beef extract supplementation promotes myoblast proliferation and myotube growth in C2C12 cells. Eur J Nutr 2020; 59:3735-3743. [PMID: 32100115 DOI: 10.1007/s00394-020-02205-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Accepted: 02/12/2020] [Indexed: 02/05/2023]
Abstract
PURPOSE We previously determined that the intake of beef extract for 4 weeks increases skeletal muscle mass in rats. Thus, this study aimed to clarify whether beef extract has a hypertrophic effect on muscle cells and to determine the signaling pathway underlying beef extract-induced myotube hypertrophy. METHODS We assessed the effects of beef extract supplement on mouse C2C12 skeletal muscle cell proliferation and differentiation and myotube growth. In addition, the phosphorylation of Akt, ERK1/2, and mTOR following beef extract supplementation was examined by western blotting. Furthermore, the bioactive constituents of beef extract were examined using amino acid analysis and dialysis. RESULTS In the proliferative stage, beef extract significantly increased myoblast proliferation. In the differentiation stage, beef extract supplementation did not promote myoblast differentiation. In mature myotubes, beef extract supplementation increased myotube diameter and promoted protein synthesis. Although Akt and ERK1/2 levels were not affected, beef extract supplementation increased mTOR phosphorylation, which indicated that the mTOR pathway mediates beef extract-induced myotube hypertrophy. The hypertrophic activity was observed in fractions of > 7000 Da. CONCLUSIONS Beef extract promoted C2C12 myoblast proliferation and C2C12 myotube hypertrophy. Myotube hypertrophy was potentially induced by mTOR activation and active components in beef extract were estimated to be > 7000 Da.
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Liu XH, De Gasperi R, Bauman WA, Cardozo CP. Nandrolone-induced nuclear accumulation of MyoD protein is mediated by Numb, a Notch inhibitor, in C2C12 myoblasts. Physiol Rep 2018; 6. [PMID: 29333723 PMCID: PMC5789652 DOI: 10.14814/phy2.13520] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Revised: 10/26/2017] [Accepted: 10/27/2017] [Indexed: 11/24/2022] Open
Abstract
Signaling via the androgen receptor (AR) stimulates myogenic progenitor differentiation. In addition, myogenic differentiation factor D (MyoD) and Numb, a Notch inhibitor, play key roles in regulating myogenic differentiation. Nandrolone, an anabolic steroid, upregulates both MyoD and Numb expression in myogenic cells. However, the molecular mechanisms by which MyoD is upregulated by nandrolone are unclear. Moreover, the potential crosstalk between nandrolone, MyoD, and Numb is not well understood. With these considerations in mind, we examined the effects of nandrolone on the expression of MyoD mRNA and protein, and determined the interactions of MyoD and Numb in the presence or absence of nandrolone in differentiating C2C12 myoblasts. Nandrolone increased MyoD mRNA and protein expression and significantly enhanced nuclear translocation of MyoD protein. The later effect of nandrolone was blunted by siRNA against Numb. Immunoprecipitation (IP) studies confirmed that Numb forms complexes with MyoD. Chromatin IP revealed that in the presence of nandrolone, Numb is recruited to a region of the MyH7 promotor containing the E‐box to which MyoD binds. These data indicate that nandrolone‐regulated MyoD activation occurs mainly through a posttranslational mechanism which promotes MyoD nuclear accumulation, and suggest that this effect of nandrolone is, at least in part, mediated by Numb.
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Affiliation(s)
- Xin-Hua Liu
- National Center for the Medical Consequences of Spinal Cord Injury, James J. Peter VA Medical Center, Bronx, New York.,Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Rita De Gasperi
- National Center for the Medical Consequences of Spinal Cord Injury, James J. Peter VA Medical Center, Bronx, New York.,Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, New York
| | - William A Bauman
- National Center for the Medical Consequences of Spinal Cord Injury, James J. Peter VA Medical Center, Bronx, New York.,Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York.,Department of Rehabilitation Medicine, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Christopher P Cardozo
- National Center for the Medical Consequences of Spinal Cord Injury, James J. Peter VA Medical Center, Bronx, New York.,Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York.,Department of Rehabilitation Medicine, Icahn School of Medicine at Mount Sinai, New York, New York.,Department of Pharmacologic Sciences, Icahn School of Medicine at Mount Sinai, New York, New York
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4
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Camerino GM, Desaphy JF, De Bellis M, Capogrosso RF, Cozzoli A, Dinardo MM, Caloiero R, Musaraj K, Fonzino A, Conte E, Jagerschmidt C, Namour F, Liantonio A, De Luca A, Conte Camerino D, Pierno S. Effects of Nandrolone in the Counteraction of Skeletal Muscle Atrophy in a Mouse Model of Muscle Disuse: Molecular Biology and Functional Evaluation. PLoS One 2015; 10:e0129686. [PMID: 26066046 PMCID: PMC4466268 DOI: 10.1371/journal.pone.0129686] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2014] [Accepted: 05/12/2015] [Indexed: 11/29/2022] Open
Abstract
Muscle disuse produces severe atrophy and a slow-to-fast phenotype transition in the postural Soleus (Sol) muscle of rodents. Antioxidants, amino-acids and growth factors were ineffective to ameliorate muscle atrophy. Here we evaluate the effects of nandrolone (ND), an anabolic steroid, on mouse skeletal muscle atrophy induced by hindlimb unloading (HU). Mice were pre-treated for 2-weeks before HU and during the 2-weeks of HU. Muscle weight and total protein content were reduced in HU mice and a restoration of these parameters was found in ND-treated HU mice. The analysis of gene expression by real-time PCR demonstrates an increase of MuRF-1 during HU but minor involvement of other catabolic pathways. However, ND did not affect MuRF-1 expression. The evaluation of anabolic pathways showed no change in mTOR and eIF2-kinase mRNA expression, but the protein expression of the eukaryotic initiation factor eIF2 was reduced during HU and restored by ND. Moreover we found an involvement of regenerative pathways, since the increase of MyoD observed after HU suggests the promotion of myogenic stem cell differentiation in response to atrophy. At the same time, Notch-1 expression was down-regulated. Interestingly, the ND treatment prevented changes in MyoD and Notch-1 expression. On the contrary, there was no evidence for an effect of ND on the change of muscle phenotype induced by HU, since no effect of treatment was observed on the resting gCl, restCa and contractile properties in Sol muscle. Accordingly, PGC1α and myosin heavy chain expression, indexes of the phenotype transition, were not restored in ND-treated HU mice. We hypothesize that ND is unable to directly affect the phenotype transition when the specialized motor unit firing pattern of stimulation is lacking. Nevertheless, through stimulation of protein synthesis, ND preserves protein content and muscle weight, which may result advantageous to the affected skeletal muscle for functional recovery.
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Affiliation(s)
- Giulia Maria Camerino
- Section of Pharmacology, Dept. of Pharmacy & Drug Sciences, University of Bari “Aldo Moro”, Bari, Italy
| | - Jean-François Desaphy
- Section of Pharmacology, Dept. of Pharmacy & Drug Sciences, University of Bari “Aldo Moro”, Bari, Italy
| | - Michela De Bellis
- Section of Pharmacology, Dept. of Pharmacy & Drug Sciences, University of Bari “Aldo Moro”, Bari, Italy
| | | | - Anna Cozzoli
- Section of Pharmacology, Dept. of Pharmacy & Drug Sciences, University of Bari “Aldo Moro”, Bari, Italy
| | - Maria Maddalena Dinardo
- Section of Pharmacology, Dept. of Pharmacy & Drug Sciences, University of Bari “Aldo Moro”, Bari, Italy
| | - Roberta Caloiero
- Section of Pharmacology, Dept. of Pharmacy & Drug Sciences, University of Bari “Aldo Moro”, Bari, Italy
| | - Kejla Musaraj
- Section of Pharmacology, Dept. of Pharmacy & Drug Sciences, University of Bari “Aldo Moro”, Bari, Italy
| | - Adriano Fonzino
- Section of Pharmacology, Dept. of Pharmacy & Drug Sciences, University of Bari “Aldo Moro”, Bari, Italy
| | - Elena Conte
- Section of Pharmacology, Dept. of Pharmacy & Drug Sciences, University of Bari “Aldo Moro”, Bari, Italy
| | | | | | - Antonella Liantonio
- Section of Pharmacology, Dept. of Pharmacy & Drug Sciences, University of Bari “Aldo Moro”, Bari, Italy
| | - Annamaria De Luca
- Section of Pharmacology, Dept. of Pharmacy & Drug Sciences, University of Bari “Aldo Moro”, Bari, Italy
| | - Diana Conte Camerino
- Section of Pharmacology, Dept. of Pharmacy & Drug Sciences, University of Bari “Aldo Moro”, Bari, Italy
| | - Sabata Pierno
- Section of Pharmacology, Dept. of Pharmacy & Drug Sciences, University of Bari “Aldo Moro”, Bari, Italy
- * E-mail:
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Qin W, Pan J, Wu Y, Bauman WA, Cardozo C. Anabolic steroids activate calcineurin-NFAT signaling and thereby increase myotube size and reduce denervation atrophy. Mol Cell Endocrinol 2015; 399:336-45. [PMID: 25450864 DOI: 10.1016/j.mce.2014.09.025] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/29/2014] [Revised: 07/22/2014] [Accepted: 09/24/2014] [Indexed: 01/11/2023]
Abstract
Anabolic androgens have been shown to reduce muscle loss due to immobilization, paralysis and many other medical conditions, but the molecular basis for these actions is poorly understood. We have recently demonstrated that nandrolone, a synthetic androgen, slows muscle atrophy after nerve transection associated with down-regulation of regulator of calcineurin 2 (RCAN2), a calcineurin inhibitor, suggesting a possible role of calcineurin-NFAT signaling. To test this possibility, rat gastrocnemius muscle was analyzed at 56 days after denervation. In denervated muscle, calcineurin activity declined and NFATc4 was excluded from the nucleus and these effects were reversed by nandrolone. Similarly, nandrolone increased calcineurin activity and nuclear NFATc4 levels in cultured L6 myotubes. Nandrolone also induced cell hypertrophy that was blocked by cyclosporin A or overexpression of RCAN2. Finally protection against denervation atrophy by nandrolone in rats was blocked by cyclosporin A. These results demonstrate for the first time that nandrolone activates calcineurin-NFAT signaling, and that such signaling is important in nandrolone-induced cell hypertrophy and protection against paralysis-induced muscle atrophy.
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Affiliation(s)
- Weiping Qin
- Center of Excellence for the Medical Consequences of Spinal Cord Injury, James J. Peters VA Medical Center, Bronx, New York 10468, USA; Departments of Medicine, Mount Sinai School of Medicine, New York, New York 10029, USA.
| | - Jiangping Pan
- Center of Excellence for the Medical Consequences of Spinal Cord Injury, James J. Peters VA Medical Center, Bronx, New York 10468, USA
| | - Yong Wu
- Center of Excellence for the Medical Consequences of Spinal Cord Injury, James J. Peters VA Medical Center, Bronx, New York 10468, USA
| | - William A Bauman
- Center of Excellence for the Medical Consequences of Spinal Cord Injury, James J. Peters VA Medical Center, Bronx, New York 10468, USA; Departments of Medicine, Mount Sinai School of Medicine, New York, New York 10029, USA; Rehabilitation Medicine, Mount Sinai School of Medicine, New York, New York 10029, USA
| | - Christopher Cardozo
- Center of Excellence for the Medical Consequences of Spinal Cord Injury, James J. Peters VA Medical Center, Bronx, New York 10468, USA; Departments of Medicine, Mount Sinai School of Medicine, New York, New York 10029, USA; Rehabilitation Medicine, Mount Sinai School of Medicine, New York, New York 10029, USA.
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Isaacs J, Feher J, Shall M, Vota S, Fox MA, Mallu S, Razavi A, Friebe I, Shah S, Spita N. Effects of nandrolone on recovery after neurotization of chronically denervated muscle in a rat model. J Neurosurg 2013; 119:914-23. [PMID: 23829817 DOI: 10.3171/2013.5.jns121837] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECT Suboptimal recovery following repair of major peripheral nerves has been partially attributed to denervation atrophy. Administration of anabolic steroids in conjunction with neurotization may improve functional recovery of chronically denervated muscle. The purpose of this study was to evaluate the effect of the administration of nandrolone on muscle recovery following prolonged denervation in a rat model. METHODS Eight groups of female Sprague-Dawley rats (15 rats per group, 120 in all) were divided into 3- or 6-month denervated hind limb and sham surgery groups and, then, nandrolone treatment groups and sham treatment groups. Evaluation of treatment effects included nerve conduction, force of contraction, comparative morphology, histology (of muscle fibers), protein electrophoresis (for muscle fiber grouping), and immunohistochemical evaluation. RESULTS Although a positive trend was noted, neither reinnervated nor normal muscle showed a statistically significant increase in peak muscle force following nandrolone treatment. Indirect measures, including muscle mass (weight and diameter), muscle cell size, muscle fiber type, and satellite cell counts, all failed to support significant anabolic effect. CONCLUSIONS There does not seem to be a functional benefit from nandrolone treatment following reinnervation of either mild or moderately atrophic muscle (related to prolonged denervation) in a rodent model.
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Affiliation(s)
- Jonathan Isaacs
- Division of Hand Surgery, Department of Orthopaedic Surgery, and
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Liu XH, Wu Y, Yao S, Levine AC, Kirschenbaum A, Collier L, Bauman WA, Cardozo CP. Androgens up-regulate transcription of the Notch inhibitor Numb in C2C12 myoblasts via Wnt/β-catenin signaling to T cell factor elements in the Numb promoter. J Biol Chem 2013; 288:17990-8. [PMID: 23649620 DOI: 10.1074/jbc.m113.478487] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Androgen signaling via the androgen receptor is a key pathway that contributes to development, cell fate decisions, and differentiation, including that of myogenic progenitors. Androgens and synthetic steroids have well established anabolic actions on skeletal muscle. Wnt and Notch signaling pathways are also essential to myogenic cell fate decisions during development and tissue repair. However, the interactions among these pathways are largely unknown. Androgenic regulation of Wnt signaling has been reported. Nandrolone, an anabolic steroid, has been shown to inhibit Notch signaling and up-regulate Numb, a Notch inhibitor. To elucidate the mechanisms of interaction between nandrolone and Wnt/Notch signaling, we investigated the effects of nandrolone on Numb expression and Wnt signaling and determined the roles of Wnt signaling in nandrolone-induced Numb expression in C2C12 myoblasts. Nandrolone increased Numb mRNA and protein levels and T cell factor (Tcf) transcriptional activity via inhibition of glycogen synthase kinase 3β. Up-regulation of Numb expression by nandrolone was blocked by the Wnt inhibitors, sFRP1 and DKK1, whereas Wnt3a increased Numb mRNA and protein expression. In addition, we observed that the proximal promoter of the Numb gene had functional Tcf binding elements to which β-catenin was recruited in a manner enhanced by both nandrolone and Wnt3a. Moreover, site-directed mutagenesis indicated that the Tcf binding sites in the Numb promoter are required for the nandrolone-induced Numb transcriptional activation in this cell line. These results reveal a novel molecular mechanism underlying up-regulation of Numb transcription with a critical role for increased canonical Wnt signaling. In addition, the data identify Numb as a novel target gene of the Wnt signaling pathway by which Wnts would be able to inhibit Notch signaling.
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Affiliation(s)
- Xin-Hua Liu
- James J. Peter Veterans Affairs Medical Center, Bronx, New York 10468, USA
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Wu Y, Zhao J, Zhao W, Pan J, Bauman WA, Cardozo CP. Nandrolone normalizes determinants of muscle mass and fiber type after spinal cord injury. J Neurotrauma 2012; 29:1663-75. [PMID: 22208735 DOI: 10.1089/neu.2011.2203] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Spinal cord injury (SCI) results in atrophy of skeletal muscle and changes from slow oxidative to fast glycolytic fibers, which may reflect reduced levels of peroxisome proliferator-activated receptor gamma coactivator-1α (PGC-1α), increased myostatin signaling, or both. In animals, testosterone reduces loss of muscle fiber cross-sectional area and activity of enzymes of energy metabolism. To identify the molecular mechanisms behind the benefits of androgens on paralyzed muscle, male rats were spinal cord transected and treated for 8 weeks with vehicle, testosterone at a physiological replacement dose, or testosterone plus nandrolone, an anabolic steroid. Treatments were initiated immediately after SCI and continued until the day animals were euthanized. In the SCI animals, gastrocnemius muscle mass was significantly increased by testosterone plus nandrolone, but not by testosterone alone. Both treatments significantly reduced nuclear content of Smad2/3 and mRNA levels of activin receptor IIB and follistatin-like 3. Testosterone alone or with nandrolone reversed SCI-induced declines in cellular and nuclear levels of PGC-1α protein and PGC-1α mRNA levels. For PGC-1α target genes, testosterone plus nandrolone partially reversed SCI-induced decreases in levels of proteins without corresponding increases in their mRNA levels. Thus, the findings demonstrate that following SCI, signaling through activin receptors and Smad2/3 is increased, and that androgens suppress activation of this signaling pathway. The findings also indicate that androgens upregulate PGC-1α in paralyzed muscle and promote its nuclear localization, but that these effects are insufficient to fully activate transcription of PGC-1α target genes. Furthermore, the transcription of these genes is not tightly coupled with their translation.
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Affiliation(s)
- Yong Wu
- Center of Excellence for the Medical Consequences of SCI, James J. Peters VA Medical Center, Bronx, NY, USA
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Physical activity induces depression-like behavior in intact male rats. Pharmacol Biochem Behav 2011; 101:85-7. [PMID: 22197713 DOI: 10.1016/j.pbb.2011.12.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/08/2011] [Revised: 12/08/2011] [Accepted: 12/09/2011] [Indexed: 02/04/2023]
Abstract
Testosterone affects behavior. Whether regular physical training does influence these effects is unknown. The assumption that testosterone induces muscular hypertrophy if combined with physical training has not been confirmed experimentally. The aim of this study was to evaluate whether activity and/or testosterone treatment affects depression-like behavior and to observe the effects of activity and testosterone on muscle fiber diameter. Forty-three male rats were divided into 4 groups: two groups (TST act and TST lazy) were treated with testosterone (5mg/kg) and two groups were used as control (CTRL act and CTRL lazy). Two of the groups (CTRL act and TST act) underwent 2weeks of exercise. The forced swim test was used as a test of depression-like behavior. Sex steroids were measured and the diameter of skeletal muscle fibers was evaluated. Testosterone was significantly higher in both testosterone-treated groups (p<0.001). Physically active groups had higher immobility times in the forced swim test than inactive groups. Groups CTRL act and TST lazy showed significantly larger diameter of muscle fibers in comparison to the TST act group. Our results suggest that physical activity induces depression-like behavior in rats. Controversial antagonistic effects of testosterone and physical activity on muscle fiber diameter were found.
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Liu XH, Yao S, Qiao RF, Levine AC, Kirschenbaum A, Pan J, Wu Y, Qin W, Bauman WA, Cardozo CP. Nandrolone reduces activation of Notch signaling in denervated muscle associated with increased Numb expression. Biochem Biophys Res Commun 2011; 414:165-9. [PMID: 21945932 DOI: 10.1016/j.bbrc.2011.09.048] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2011] [Accepted: 09/11/2011] [Indexed: 11/24/2022]
Abstract
Nandrolone, an anabolic steroid, slows denervation-atrophy in rat muscle. The molecular mechanisms responsible for this effect are not well understood. Androgens and anabolic steroids activate Notch signaling in animal models of aging and thereby mitigate sarcopenia. To explore the molecular mechanisms by which nandrolone prevents denervation-atrophy, we investigated the effects of nandrolone on Notch signaling in denervated rat gastrocnemius muscle. Denervation significantly increased Notch activity reflected by elevated levels of nuclear Notch intracellular domain (NICD) and expression of Hey1 (a Notch target gene). Activation was greatest at 7 and 35 days after denervation but remained present at 56 days after denervation. Activation of Notch in denervated muscle was prevented by nandrolone associated with upregulated expression of Numb mRNA and protein. These data demonstrate that denervation activates Notch signaling, and that nandrolone abrogates this response associated with increased expression of Numb, suggesting a potential mechanism by which nandrolone reduces denervation-atrophy.
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Affiliation(s)
- Xin-Hua Liu
- Center of Excellence for Medical Consequences of Spinal Cord Injury, James J. Peter VA Medical Center, Bronx, NY 10468, USA
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Isaacs J, Loveland K, Mallu S, Adams S, Wodicka R. The use of anabolic steroids as a strategy in reversing denervation atrophy after delayed nerve repair. Hand (N Y) 2011; 6:142-8. [PMID: 22654697 PMCID: PMC3092896 DOI: 10.1007/s11552-011-9331-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
BACKGROUND Denervation atrophy is one factor contributing to suboptimal motor recovery following major nerve repair. The hypertrophic effects of anabolic steroids may have a potential role in improving reinnervated muscle strength after delayed repair. METHODS Forty-five immature female Sprague-Dawley rats underwent three surgeries and final testing. The tibial nerve was transected in the hind limb of the experimental (n = 13) and control (n = 14) animals and exposed, but not transected in the sham (n = 15) group animals. Three months later, once denervation atrophy was established, all transected nerves underwent repair using an autograft from the contralateral limb. After waiting an additional month to allow axonal regeneration to the gastrocnemius muscles, the rodents were implanted with a subcutaneous infusion pump. For the experimental group, nandrolone was administered over the next 30 days via this pump, while the control and sham group pumps were filled with carrier only. RESULTS Final testing, 6 weeks later, showed improved muscle contraction strength in the steroid-treated animals (72% of sham group strength) compared to control animals (57% of sham group strength, p < 0.5). A trend towards increased weight and muscle belly diameter in the steroid-treated group was not statistically significant. CONCLUSIONS These findings support the potential role of anabolic steroids in improving recovery of atrophic muscle after delayed reinnervation.
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Affiliation(s)
- Jonathan Isaacs
- Division of Hand Surgery, Department of Orthopaedic Surgery, Virginia Commonwealth University Health Systems, 1200 East Broad Street, P.O. Box 980153, Richmond, VA 23298 USA
| | - Kerry Loveland
- Division of Hand Surgery, Department of Orthopaedic Surgery, Virginia Commonwealth University Health Systems, 1200 East Broad Street, P.O. Box 980153, Richmond, VA 23298 USA
| | - Satya Mallu
- Division of Hand Surgery, Department of Orthopaedic Surgery, Virginia Commonwealth University Health Systems, 1200 East Broad Street, P.O. Box 980153, Richmond, VA 23298 USA
| | - Scott Adams
- Division of Hand Surgery, Department of Orthopaedic Surgery, Virginia Commonwealth University Health Systems, 1200 East Broad Street, P.O. Box 980153, Richmond, VA 23298 USA
| | - Ross Wodicka
- Division of Hand Surgery, Department of Orthopaedic Surgery, Virginia Commonwealth University Health Systems, 1200 East Broad Street, P.O. Box 980153, Richmond, VA 23298 USA
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Qin W, Bauman WA, Cardozo C. Bone and muscle loss after spinal cord injury: organ interactions. Ann N Y Acad Sci 2010; 1211:66-84. [PMID: 21062296 DOI: 10.1111/j.1749-6632.2010.05806.x] [Citation(s) in RCA: 125] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Spinal cord injury (SCI) results in paralysis and marked loss of skeletal muscle and bone below the level of injury. Modest muscle activity prevents atrophy, whereas much larger--and as yet poorly defined--bone loading seems necessary to prevent bone loss. Once established, bone loss may be irreversible. SCI is associated with reductions in growth hormone, IGF-1, and testosterone, deficiencies likely to exacerbate further loss of muscle and bone. Reduced muscle mass and inactivity are assumed to be contributors to the high prevalence of insulin resistance and diabetes in this population. Alterations in muscle gene expression after SCI share common features with other muscle loss states, but even so, show distinct profiles, possibly reflecting influences of neuromuscular activity due to spasticity. Changes in bone cells and markers after SCI have similarities with other conditions of unloading, although after SCI these changes are much more dramatic, perhaps reflecting the much greater magnitude of unloading. Adiposity and marrow fat are increased after SCI with intriguing, though poorly understood, implications for the function of skeletal muscle and bone cells.
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Affiliation(s)
- Weiping Qin
- Center of Excellence for the Medical Consequences of Spinal Cord Injury, James J. Peters Veterans Affairs Medical Center, Bronx, New York, USA.
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13
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Kovacevic D, Rodeo SA. Biological augmentation of rotator cuff tendon repair. Clin Orthop Relat Res 2008; 466:622-33. [PMID: 18264850 PMCID: PMC2505220 DOI: 10.1007/s11999-007-0112-4] [Citation(s) in RCA: 176] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/31/2007] [Accepted: 12/31/2007] [Indexed: 02/08/2023]
Abstract
A histologically normal insertion site does not regenerate following rotator cuff tendon-to-bone repair, which is likely due to abnormal or insufficient gene expression and/or cell differentiation at the repair site. Techniques to manipulate the biologic events following tendon repair may improve healing. We used a sheep infraspinatus repair model to evaluate the effect of osteoinductive growth factors and BMP-12 on tendon-to-bone healing. Magnetic resonance imaging and histology showed increased formation of new bone and fibrocartilage at the healing tendon attachment site in the treated animals, and biomechanical testing showed improved load-to-failure. Other techniques with potential to augment repair site biology include use of platelets isolated from autologous blood to deliver growth factors to a tendon repair site. Modalities that improve local vascularity, such as pulsed ultrasound, have the potential to augment rotator cuff healing. Important information about the biology of tendon healing can also be gained from studies of substances that inhibit healing, such as nicotine and antiinflammatory medications. Future approaches may include the use of stem cells and transcription factors to induce formation of the native tendon-bone insertion site after rotator cuff repair surgery.
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Affiliation(s)
- David Kovacevic
- Laboratory for Soft Tissue Research, The Hospital for Special Surgery, New York, NY USA
| | - Scott A. Rodeo
- Sports Medicine and Shoulder Service, The Hospital for Special Surgery, 525 East 71st St., New York, NY 10021 USA
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14
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Zhao J, Zhang Y, Zhao W, Wu Y, Pan J, Bauman WA, Cardozo C. Effects of nandrolone on denervation atrophy depend upon time after nerve transection. Muscle Nerve 2008; 37:42-9. [PMID: 17763458 DOI: 10.1002/mus.20888] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Anabolic steroids prevent disuse atrophy and reverse atrophy caused by glucocorticoids. To determine whether these beneficial effects extend to denervation atrophy, we tested whether nandrolone blocked denervation atrophy acutely or reversed subacute denervation atrophy. We also tested the association of such anabolic effects with expression of MAFbx, MuRF1 (both of which accelerate denervation atrophy), and IGF-1 (which prevents such atrophy). When begun at the time of denervation, nandrolone did not alter atrophy or expression of MAFbx, MuRF1, or IGF-1 measured 3, 7, or 14 days thereafter. When nandrolone administration was begun 28 days after denervation, atrophy was significantly reduced 7 and 28 days later (16% and 30%, respectively), and this was associated with significant reductions in expression of MAFbx and MuRF1, without alterations in the expression of IGF-1. The findings indicate that the actions of nandrolone depend on time after nerve transection and that the timing of anabolic steroid administration is an important determinant of responses of atrophying muscle to these agents.
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Affiliation(s)
- Jingbo Zhao
- Department of Veterans Affairs, Room 1E-02, James J. Peters VA Medical Center, Bronx, New York 10468, USA
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15
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Shin RH, Vathana T, Giessler GA, Friedrich PF, Bishop AT, Shin AY. Isometric tetanic force measurement method of the tibialis anterior in the rat. Microsurgery 2008; 28:452-7. [DOI: 10.1002/micr.20520] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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16
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Camargo Filho JCS, Vanderlei LCM, Camargo RCT, Francischeti FA, Belangero WD, Pai VD. Efeitos do esteróide anabólico nandrolona sobre o músculo sóleo de ratos submetidos a treinamento físico através de natação: estudo histológico, histoquímico e morfométrico. REV BRAS MED ESPORTE 2006. [DOI: 10.1590/s1517-86922006000500004] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Este estudo teve por objetivo analisar as alterações histológicas, histoquímicas e morfométricas das fibras do músculo sóleo de ratos submetidos a um programa de natação, associado ou não à administração do esteróide anabólico decanoato de nandrolona. Foram utilizados 22 ratos Wistar machos, 12 dos quais receberam injeção intramuscular do esteróide (5mg/kg) e 10, óleo mineral (5mg/kg), duas vezes por semana. Os animais foram submetidos a 42 sessões de natação por nove semanas (de segunda a sexta-feira), com aumento progressivo de carga por meio do tempo de natação. Após o sacrifício, o músculo sóleo esquerdo foi retirado, imerso em n-hexana e acondicionado em nitrogênio líquido. Cortes do terço médio desse músculo foram feitos em micrótomo criostato (-20ºC) e corados pela técnica HE e pelo método histoquímico NADH-TR. Os animais submetidos a treinamento físico e a esteróide (TA) ou óleo mineral (TO) apresentaram fibras musculares com maior diâmetro, quando comparados com os animais-controle (NTA e NTO). Não houve diferença significativa entre as medidas das médias dos diâmetros das fibras dos grupos NTA e NTO e entre TA e TO. Nos grupos TA e NTA notou-se acentuado processo de fagocitose, arredondamento e hialinização das fibras musculares. Já nos grupos TA, TO e NTA observou-se perda da atividade enzimática oxidativa. Os resultados sugerem que a natação produz hipertrofia muscular de forma semelhante, tanto no grupo que recebeu esteróide como no que recebeu óleo mineral. No entanto, o grupo que recebeu esteróide apresentou sinais claros de maior degeneração muscular.
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17
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Medras M, Tworowska U, Jozkow P, Dumanski A, Dubinski A. Postoperative course and anabolic-androgenic steroid abuse - a case report. Anaesthesia 2005; 60:81-4. [PMID: 15601278 DOI: 10.1111/j.1365-2044.2004.03998.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
It is estimated that 80% of weight lifters and body-builders take anabolic-androgenic steroids. Their long-term use is associated with a variety of pathological conditions and premature death. Anabolic-androgenic steroid abuse may lead to changes in the presentation and progression of some conditions. It remains unclear whether anabolic steroids should be given to patients with a history of abuse of these drugs who are to undergo surgery. We report on a fatal outcome following surgery in a 48-year-old weight lifter.
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Affiliation(s)
- M Medras
- Department of Sports Medicine, University of Physical Education, Wroclaw, Poland.
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18
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Abstract
Anabolic-androgenic steroids (AAS) are synthetic derivatives of testosterone. According to surveys and media reports, the legal and illegal use of these drugs is gaining popularity. Testosterone restores sex drive and boosts muscle mass, making it central to 2 of society's rising preoccupations: perfecting the male body and sustaining the male libido. The anabolic effects of AAS have been questioned for decades, but recent scientific investigation of supraphysiologic doses supports the efficacy of these regimens. Testosterone has potent anabolic effects on the musculoskeletal system, including an increase in lean body mass, a dose-related hypertrophy of muscle fibers, and an increase in muscle strength. For athletes requiring speed and strength and men desiring a cosmetic muscle makeover, illegal steroids are a powerful lure, despite the risk of subjective side effects. Recent clinical studies have discovered novel therapeutic uses for physiologic doses of AAS, without any significant adverse effects in the short term. In the wake of important scientific advances during the past decade, the positive and negative effects of AAS warrant reevaluation. Guidelines for the clinical evaluation of AAS users will be presented for sports medicine practitioners.
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Affiliation(s)
- Nick A Evans
- UCLA-Orthopaedic Hospital, Los Angeles, California, USA.
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19
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Bouhlel A, Joumaa WH, Léoty C. Nandrolone decanoate treatment affects sarcoplasmic reticulum Ca(2+) ATPase function in skinned rat slow- and fast-twitch fibres. Pflugers Arch 2003; 446:728-34. [PMID: 12811564 DOI: 10.1007/s00424-003-1114-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2002] [Revised: 03/26/2003] [Accepted: 05/12/2003] [Indexed: 11/28/2022]
Abstract
The effects of anabolic-androgenic steroid administration on the function of the sarcoplasmic reticulum (SR) pump were investigated in chemically skinned fibres from the extensor digitorum longus (EDL) and soleus muscles of sedentary rats. Twenty male rats were divided into two groups, one group received an intramuscular injection of nandrolone decanoate (15 mg x kg(-1)) weekly for 8 weeks, the second received similar weekly doses of vehicle (sterile peanut oil). Compared with control muscles, nandrolone decanoate treatment reduced SR Ca(2+) loading in EDL and soleus fibres by 49% and 29%, respectively. In control and treated muscles, the rate of Ca(2+) leakage depended on the quantity of Ca(2+) loaded. Furthermore, for similar SR Ca(2+) contents, the Ca(2+) leakage rate was not significantly modified by nandrolone decanoate treatment. Nandrolone decanoate treatment thus affects Ca (2+) uptake by the SR in a fibre-type dependent manner.
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MESH Headings
- Anabolic Agents/pharmacology
- Animals
- Caffeine/pharmacology
- Calcium/metabolism
- Calcium-Transporting ATPases/drug effects
- Calcium-Transporting ATPases/metabolism
- Kinetics
- Male
- Muscle Contraction/drug effects
- Muscle Fibers, Fast-Twitch/drug effects
- Muscle Fibers, Fast-Twitch/enzymology
- Muscle Fibers, Fast-Twitch/ultrastructure
- Muscle Fibers, Slow-Twitch/drug effects
- Muscle Fibers, Slow-Twitch/enzymology
- Muscle Fibers, Slow-Twitch/ultrastructure
- Muscle, Skeletal/drug effects
- Muscle, Skeletal/enzymology
- Muscle, Skeletal/ultrastructure
- Nandrolone/analogs & derivatives
- Nandrolone/pharmacology
- Nandrolone Decanoate
- Phosphodiesterase Inhibitors/pharmacology
- Rats
- Rats, Wistar
- Saponins/pharmacology
- Sarcoplasmic Reticulum/drug effects
- Sarcoplasmic Reticulum/metabolism
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Affiliation(s)
- Aicha Bouhlel
- Laboratoire de Physiologie Générale, UMR CNRS 6018, Faculté des Sciences et des Techniques, Université de Nantes, 2 rue de la Houssinière, BP 92208, 44322, Nantes Cedex 3, France
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20
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Joumaa WH, Bouhlel A, Bigard X, Léoty C. Nandrolone decanoate pre-treatment attenuates unweighting-induced functional changes in rat soleus muscle. ACTA PHYSIOLOGICA SCANDINAVICA 2002; 176:301-9. [PMID: 12444936 DOI: 10.1046/j.1365-201x.2002.01035.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The effect of nandrolone decanoate pre-treatment (15 mg kg(-1) week(-1), for 6 weeks) was tested on the changes in mass and contractile properties of soleus muscle associated with 3 weeks of hindlimb suspension. Male rats were assigned to four groups (eight animals/group): control, nandrolone decanoate hindlimb-loaded, hindlimb-unweighted and nandrolone decanoate hindlimb-unweighted. Compared with age-matched control values, suspension induced a reduction in relative muscle mass and a shift in tension characteristics from slow-towards fast-twitch type. Nandrolone decanoate pre-treatment of suspended animals (nandrolone decanoate hindlimb-unweighted vs. nandrolone decanoate hindlimb-loaded) partially spared the relative soleus mass. Furthermore, (1) the relative twitch tension (nandrolone decanoate hindlimb-loaded: 5.4 +/- 0.7%; nandrolone decanoate hindlimb-unweighted: 5.1 +/- 0.5%), (2) the time to peak tension (nandrolone decanoate hindlimb-loaded: 152 +/- 9 ms; nandrolone decanoate hindlimb-unweighted: 167 +/- 15 ms), (3) the time constant of relaxation (nandrolone decanoate hindlimb-loaded: 274 +/- 12 ms; nandrolone decanoate hindlimb-unweighted: 245 +/- 20 ms), (4) the relative K+ contracture tension (nandrolone decanoate hindlimb-loaded: 81.7 +/- 3.8%; nandrolone decanoate hindlimb-unweighted: 86.9 +/- 4.2%) and (5) the relative caffeine contracture tension (0.5 mM) (nandrolone decanoate hindlimb-loaded: 5.2 +/- 0.8%; nandrolone decanoate hindlimb-unweighted: 5.9 +/- 1.1%) were not significantly modified. The present results demonstrate that exogenously provided nandrolone decanoate pre-treatment attenuates functional changes occurring in soleus muscle subject to unweighting.
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Affiliation(s)
- W H Joumaa
- Laboratoire de Physiologie Générale, CNRS UMR 6018, Faculté des Sciences et des Techniques, Université de Nantes, 2 rue de laHoussinière, Nantes, France
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21
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Joumaa WH, Serrurier B, Bigard X, Léoty C. Nandrolone decanoate treatment induces changes in contractile responses of rat untrained fast-twitch skeletal muscle. ACTA PHYSIOLOGICA SCANDINAVICA 2002; 175:189-99. [PMID: 12100358 DOI: 10.1046/j.1365-201x.2002.00988.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
This investigation was designed to examine whether short-term administration of anabolic-androgenic steroids (AAS) (nandrolone decanoate) could produce changes in contractile responses of untrained rat fast- (edl) and slow- (soleus) twitch skeletal muscle. Twenty male rats were divided into two groups, one group received weekly (for 6 weeks) an intramuscular injection of AAS, nandrolone decanoate (15 mg kg(-1)) and the second group received weekly the similar doses of vehicle (sterile peanut oil). In edl intact isolated small bundles (two to four cells), it was found that nandrolone decanoate treatment increases the K+ contracture tension (146 mM) relative to maximum tension by 56%, whereas no change was observed in the time to peak tension and in the time constant of relaxation. By contrast, in treated soleus muscle, compared with control, no significant modification was found in the K+ contracture characteristics. The change in edl contractile responses was associated with a shift to more negative potential of the voltage-dependence activation and the steady-state inactivation curves which also shifted leftward in treated soleus fibres. Furthermore, in edl skinned Triton X-100 fibres, the Ca2+ sensitivity of contractile proteins (pCa50) was increased, while electrophoresis analysis indicates no significant effect of nandrolone decanoate treatment on myosin heavy chain (MHC) isoforms. The present results show that nandrolone decanoate treatment produces more pronounced changes in untrained fast muscle function rather than soleus by acting at different levels of the excitation-contraction coupling mechanism without changes in the MHC isoforms and that contractile responses became similar to those found in soleus muscle.
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Affiliation(s)
- W H Joumaa
- Laboratoire de Physiologie Générale, CNRS UMR 6018, Faculté des Sciences et des Techniques, Université de Nantes, Nantes, France
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22
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Skoura C, Mourouzis C, Saranteas T, Chatzigianni E, Tesseromatis C. Masseteric hypertrophy associated with administration of anabolic steroids and unilateral mastication: a case report. ORAL SURGERY, ORAL MEDICINE, ORAL PATHOLOGY, ORAL RADIOLOGY, AND ENDODONTICS 2001; 92:515-8. [PMID: 11709687 DOI: 10.1067/moe.2001.115983] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In this report we present a patient with unilateral masseteric hypertrophy who used anabolic steroids and was chewing entirely unilaterally for 1 month. Computed tomography and histologic examination were used to confirm the diagnosis. The combined action of unilateral mastication and anabolic steroid use is probably responsible for the rapid development of unilateral masseteric hypertrophy.
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Affiliation(s)
- C Skoura
- Department of Oral and Maxillofacial Surgery, General District Hospital of Athens KAT, Greece
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23
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Abstract
BACKGROUND Cancer-associated cachexia is a syndrome of progressive wasting of body energy (adipose) and protein (skeletal muscle) reserves. Cachexia occurs in a majority of advanced cancer patients. Extensive loss of muscle mass is one factor likely to be associated with fatigue in cancer patients. METHODS Research with animal models of cancer-associated cachexia that have focused on the processes of muscle protein synthesis and degradation are reviewed in this article. Modulation of the production or action of anabolic and catabolic factors known to regulate muscle protein synthesis and degradation have been employed to identify causal factors in muscle wasting. RESULTS Impaired muscle protein synthesis and activation of catabolism participate in cancer-associated muscle atrophy. The relative roles of multiple factors, including a low level of physical activity, poor nutritional status, and secretion of catabolic mediators of host or tumor origin, are discussed herein. A diversity of putative mediators has been identified, and a number of common themes are beginning to emerge. CONCLUSIONS Multiple distinct catabolic profiles exist in animal models of cancer-associated muscle wasting. The presence of these catabolic phenotypes in cancer patients must be determined, and the application of successful treatments will depend on our ability to determine which categories of patients experience the greatest benefit.
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Affiliation(s)
- V E Baracos
- Department of Agricultural, Food and Nutritional Science and Department of Oncology, University of Alberta, Edmonton, Alberta, Canada.
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