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Santos CP, Aguiar AF, Giometti IC, Mariano TB, de Freitas CEA, Nai GA, de Freitas SZ, Pai-Silva MD, Pacagnelli FL. High final energy of gallium arsenide laser increases MyoD gene expression during the intermediate phase of muscle regeneration after cryoinjury in rats. Lasers Med Sci 2018; 33:843-850. [PMID: 29333581 DOI: 10.1007/s10103-018-2439-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2017] [Accepted: 01/04/2018] [Indexed: 01/19/2023]
Abstract
The aim of this study was to determine the effects of gallium arsenide (GaAs) laser on IGF-I, MyoD, MAFbx, and TNF-α gene expression during the intermediate phase of muscle regeneration after cryoinjury 21 Wistar rats were divided into three groups (n = 7 per group): untreated with no injury (control group), cryoinjury without GaAs (injured group), and cryoinjury with GaAs (GaAs-injured group). The cryoinjury was induced in the central region of the tibialis anterior muscle (TA). The region injured was irradiated once a day during 14 days using GaAs laser (904 nm; spot size 0.035 cm2, output power 50 mW; energy density 69 J cm-2; exposure time 4 s per point; final energy 4.8 J). Twenty-four hours after the last application, the right and left TA muscles were collected for histological (collagen content) and molecular (gene expression of IGF-I, MyoD, MAFbx, and TNF-α) analyses, respectively. Data were analyzed using one-way ANOVA at P < 0.05. There were no significant (P > 0.05) differences in collagen density and IGF-I gene expression in all experimental groups. There were similar (P < 0.05) decreases in MAFbx and TNF-α gene expression in the injured and GaAs-injured groups, compared to control group. The MyoD gene expression increased (P = 0.008) in the GaAs-injured group, but not in the injured group (P = 0.338), compared to control group. GaAs laser therapy had a positive effect on MyoD gene expression, but not IGF-I, MAFbx, and TNF-α, during intermediary phases (14 days post-injury) of muscle repair.
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Affiliation(s)
- Caroline Pereira Santos
- Department of Physical Therapy, University of Western São Paulo (UNOESTE), Presidente Prudente, São Paulo, Brazil
| | - Andreo Fernando Aguiar
- Center of Research in Health Science, North University of Paraná (UNOPAR), Avenue Paris, 675, Jardim Piza, Londrina, PR, 86041-120, Brazil.
| | - Ines Cristina Giometti
- Department of Physical Therapy, University of Western São Paulo (UNOESTE), Presidente Prudente, São Paulo, Brazil
| | - Thaoan Bruno Mariano
- Department of Physical Therapy, University of Western São Paulo (UNOESTE), Presidente Prudente, São Paulo, Brazil
| | | | - Gisele Alborghetti Nai
- Department of Physical Therapy, University of Western São Paulo (UNOESTE), Presidente Prudente, São Paulo, Brazil
| | - Selma Zambelli de Freitas
- Department of Physical Therapy, University of Western São Paulo (UNOESTE), Presidente Prudente, São Paulo, Brazil
| | - Maeli Dal Pai-Silva
- Department of Morphology, São Paulo State University (UNESP), Botucatu, São Paulo, Brazil
| | - Francis Lopes Pacagnelli
- Department of Physical Therapy, University of Western São Paulo (UNOESTE), Presidente Prudente, São Paulo, Brazil
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Cavalcante WLG, Hernandez-Oliveira S, Galbiatti C, Randazzo-Moura P, Rocha T, Ponce-Soto L, Marangoni S, Pai-Silva MD, Gallacci M, da Cruz-Höfling MA, Rodrigues-Simioni L. Biological characterization of Bothrops marajoensis snake venom. J Venom Res 2011; 2:37-41. [PMID: 22091348 PMCID: PMC3211074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/22/2011] [Revised: 10/03/2011] [Accepted: 10/11/2011] [Indexed: 11/05/2022]
Abstract
This study describes the effects of Bothrops marajoensis venom (Marajó lancehead) on isolated neuromuscular preparations of chick biventer cervicis (CBC) and mouse phrenic nerve-diaphragm (PND). At low concentrations (1µg/ml for CBC and 5µg/ml for PND), the venom exhibited a neuromuscular blocking without any damaging effect on the muscle integrity. At higher concentration (20μg/ml for PND), together with the neuromuscular blockade, there was a moderate myonecrosis. The results show differences between mammalian and avian preparations in response to venom concentration; the avian preparation was more sensitive to venom neurotoxic effect than the mammalian preparation. The possible presynaptic mechanism underlying the neuromuscular blocking effect was reinforced by the observed increase in MEPPs at the same time (at 15min) when the facilitation of twitch tension occurred. These results indicate that the B. marajoensis venom produced neuromuscular blockade, which appeared to be presynaptic at low concentrations with a postsynaptic component at high concentrations, leading to muscle oedema. These observations demand the fractionation of the crude venom and characterization of its active components for a better understanding of its biological dynamics.
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Affiliation(s)
- Walter LG Cavalcante
- αDepartment of Pharmacology, Faculty of Medical Sciences,¥Department of Pharmacology, São Paulo State University, Unesp, Botucatu, SP, Brazil
| | | | | | | | | | - Luis Ponce-Soto
- λDepartment of Biochemistry, Biology Institute Universidade Estadual de Campinas (UNICAMP), CP 6111, 13083-970, Campinas, SP, Brazil
| | - Sérgio Marangoni
- λDepartment of Biochemistry, Biology Institute Universidade Estadual de Campinas (UNICAMP), CP 6111, 13083-970, Campinas, SP, Brazil
| | | | - Márcia Gallacci
- ¥Department of Pharmacology, São Paulo State University, Unesp, Botucatu, SP, Brazil
| | | | - Léa Rodrigues-Simioni
- αDepartment of Pharmacology, Faculty of Medical Sciences,*Correspondence to: Léa Rodrigues-Simioni, E-mail: (LRS), Tel: +55 19 35219536, Fax: +55 19 32892968
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de Almeida FLA, Pessotti NS, Pinhal D, Padovani CR, Leitão NDJ, Carvalho RF, Martins C, Portella MC, Dal Pai-Silva M. Quantitative expression of myogenic regulatory factors MyoD and myogenin in pacu (Piaractus mesopotamicus) skeletal muscle during growth. Micron 2010; 41:997-1004. [DOI: 10.1016/j.micron.2010.06.012] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2010] [Revised: 06/22/2010] [Accepted: 06/23/2010] [Indexed: 11/27/2022]
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Martinez PF, Okoshi K, Zornoff LAM, Carvalho RF, Oliveira Junior SA, Lima ARR, Campos DHS, Damatto RL, Padovani CR, Nogueira CR, Dal Pai-Silva M, Okoshi MP. Chronic heart failure-induced skeletal muscle atrophy, necrosis, and changes in myogenic regulatory factors. Med Sci Monit 2010; 16:BR374-BR383. [PMID: 21119570] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2023] Open
Abstract
BACKGROUND Although intrinsic skeletal muscle abnormalities can influence exercise intolerance during heart failure (HF), the factors responsible for muscle changes have not been elucidated. In this study we evaluated the expression of myogenic regulatory factors (MRF), myosin heavy chain (MyHC) isoforms, and fiber trophism in the soleus muscle of rats with myocardial infarction-induced heart failure. METHOD/RESULTS Six months after surgery, 2 groups of rats were studied: sham, and infarcted rats with HF (MI/HF+, MI size: 41.1±6.3% of total left ventricular area). In the infarcted group, microscopic evaluation revealed scattered foci of fiber necrosis in combination with inflammatory cells, phagocytosis, and increased fibrous tissue. The frequency of necrotic fibers was significantly higher in the MI/HF+ group than in the sham. The MI/HF+ group had atrophy of type I, IC/IIC, and IIA fibers compared to the sham group (P<0.05). MyoD gene expression was higher in the MI/HF+ group (sham: 1.00±0.49; MI/HF+: 2.53±0.71 arbitrary units; P<0.001). Myogenin and MRF4 gene expression was similar in both groups. Myogenin protein levels were reduced in the MI/HF+ group (sham: 1.00±0.21; MI/HF+: 0.74±0.21 arbitrary units; P=0.026). MyoD and MRF4 protein levels, as well as the MyHC distribution, were not different between groups. The MI/HF+ group had higher TNF-α and IL-6 serum concentrations than the sham group. CONCLUSIONS Heart failure-induced skeletal muscle atrophy is combined with fiber necrosis, increased MyoD gene expression and decreased myogenin protein levels.
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Affiliation(s)
- Paula F Martinez
- Department of Internal Medicine, Botucatu Medical School, Sao Paulo State University, UNESP (Universidad Estadual Paulista), Sao Paulo, Brazil
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Oliveira Junior SA, Dal Pai-Silva M, Martinez PF, Lima-Leopoldo AP, Campos DHS, Leopoldo AS, Okoshi MP, Okoshi K, Padovani CR, Cicogna AC. Diet-induced obesity causes metabolic, endocrine and cardiac alterations in spontaneously hypertensive rats. Med Sci Monit 2010; 16:BR367-BR373. [PMID: 21119569] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2023] Open
Abstract
BACKGROUND Although obesity has been associated with several effects in rodents, few investigations have evaluated the metabolic, endocrine, and cardiac parameters of spontaneously hypertensive rats (SHR) with dietary-induced obesity. The current study analyzed the influence of dietary-induced obesity on metabolic, endocrine, and cardiac characteristics in SHR. MATERIAL/METHODS Male SHR were distributed in 2 groups: C-SHR (n=10) and OB-SHR (n=10). While C-SHR received a standard commercial diet (CD; 3.2 kcal/g), OB-SHR were submitted to a hypercaloric diet (HD; 4.6 kcal/g) for 20 weeks. Nutritional, metabolic, and endocrine evaluation involved measurement of calorie intake, dietary efficiency, body weight, adiposity, glycemia, triacylglycerol, insulin, and leptin. Cardiovascular evaluation integrated systolic blood pressure (SBP), echocardiography, gross and ultrastructural morphology, and myosin heavy chain (MHC) analyses of the myocardium. RESULTS Animals in OB-SHR had greater values of BW, adiposity, triacylglycerol, and leptin and impaired glycemic tolerance compared with the C-SHR group. In the cardiovascular context, dietary-induced obesity increased interstitial collagen, the cardiomyocyte area, and the relative expression of beta-MHC, and well as beta-/alpha-isoform ratio of MHC. Likewise, OB-SHR showed ultrastructural morphologic alterations, with loss and disorganization of myofilaments, lipid droplets, severe mitochondrial damage, and T-tubule dilation. Concerning the in-vivo cardiovascular profile, although SBP and systolic function were unchanged by dietary-induced obesity, echocardiography results evidenced impaired diastolic function in OB-SHR in relation to their control counterparts. CONCLUSIONS Diet-induced obesity was associated with endocrine alterations, and it accentuated cardiac remodeling, promoting diastolic dysfunction of restrictive filling pattern in the SHR strain.
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Leopoldo AS, Sugizaki MM, Lima-Leopoldo AP, do Nascimento AF, Luvizotto RDAM, de Campos DHS, Okoshi K, Dal Pai-Silva M, Padovani CR, Cicogna AC. Cardiac remodeling in a rat model of diet-induced obesity. Can J Cardiol 2010; 26:423-9. [PMID: 20931095 DOI: 10.1016/s0828-282x(10)70440-2] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
The mechanisms by which diet-induced obesity cause remodeling and cardiac dysfunction are still unknown. Interstitial collagen and myocardial ultrastructure are important in the development of left ventricular hypertrophy, and are essential to the adaptive and maladaptive changes associated with obesity. Thus, the accumulation of collagen and ultrastructural damage may contribute to cardiac dysfunction in obesity. The purpose of the present study was to investigate cardiac function in a rat model of diet-induced obesity and to test the hypothesis that cardiac dysfunction induced by obesity is related to myocardial collagen deposition and ultrastructural damage. Thirty-day-old male Wistar rats were fed standard (control [C]) and hypercaloric diets (obese [Ob]) for 15 weeks. Cardiac function was evaluated by echocardiogram and isolated left ventricle papillary muscle. Cardiac morphology was assessed by histology and electron microscopy. Compared with C rats, Ob rats had increased body fat, systolic blood pressure and area under the curve for glucose, leptin and insulin plasma concentrations. Echocardiographic indexes indicated that Ob rats had increased left ventricular mass, increased systolic stress and depressed systolic function. Analysis of the isolated papillary muscle was consistent with higher myocardial stiffness in Ob compared with C rats. The Ob rats had an increase in myocardial collagen and marked ultrastructural changes compared with C rats. Obesity promotes pathological cardiac remodeling with systolic dysfunction and an increase in myocardial stiffness, which, in turn, is probably related to afterload elevation and cardiac fibrosis. Obesity also causes damage to myocardial ultrastructure, but its effect on myocardial function needs to be further clarified.
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Affiliation(s)
- André Soares Leopoldo
- Department of Clinical and Cardiology, Universidade Estadual Paulista "Julio de Mesquita Filho", Botucatu, São Paulo, Brazil.
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Oliveira SA, Okoshi K, Lima-Leopoldo AP, Leopoldo AS, Campos DHS, Martinez PF, Okoshi MP, Padovani CR, Pai-Silva MD, Cicogna AC. Nutritional and cardiovascular profiles of normotensive and hypertensive rats kept on a high fat diet. Arq Bras Cardiol 2010; 93:526-33. [PMID: 20084315 DOI: 10.1590/s0066-782x2009001100014] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2008] [Accepted: 10/21/2008] [Indexed: 11/22/2022] Open
Abstract
BACKGROUND Although a high fat diet (HFD) promotes nutritional and heart disorders, few studies have assessed its influence in normotensive Wistar-Kyoto rats (WKY) and spontaneously hypertensive rats (SHR). OBJECTIVE To evaluate and compare the nutritional and cardiovascular profiles of WKY and SHR on a high fat diet. METHODS 20 WKY and 20 SHR were divided into four groups: Control-WKY (C-WKY), HFD-WKY, Control-SHR (C-SHR) and HFD-SHR. The C and HFD groups received, respectively, a normocaloric diet and a HFD for 20 weeks. The following features were evaluated: body weight (BW), adiposity, blood glucose, serum lipids, with measurements of total cholesterol and triacylglycerol levels, insulin and leptin. The cardiovascular study included the systolic blood pressure (SBP), a cardiopulmonary anatomical evaluation, an echocardiography and heart histology. RESULTS The SHR had BW, adiposity, glucose, cholesterol, triacylglycerol, leptin and insulin levels lower than the WKY. In SHR, the caloric intake increased with HFD. In WKY, the HFD increased energy efficiency, adiposity and blood leptin, and reduced glucose. In the cardiovascular assessment, the SHR had SBP, pulmonary moisture, myocardial hypertrophy and interstitial fibrosis higher than the WKY (p <0.01); the cardiac function was similar in both strains. The HFD reduced the ventricular systolic diameter in the WKY and increased the mitral E/A ratio, the diastolic thickness of the interventricular septum and the posterior wall, as well as the interstitial fibrosis of the left ventricle. (Arq Bras Cardiol 2009; 93(5) : 487-494) CONCLUSION Although it had not significantly affected the nutritional profile of the SHR, the treatment increased cardiac remodeling and precipitated the emergence of ventricular diastolic dysfunction. In WKY, the diet increased adiposity and leptinemia, and promoted non-significant cardiovascular changes.
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Oliveira Junior SA, Dal Pai-Silva M, Martinez PF, Campos DHS, Lima-Leopoldo AP, Leopoldo AS, Nascimento AF, Okoshi MP, Okoshi K, Padovani CR, Cicogna AC. Differential nutritional, endocrine, and cardiovascular effects in obesity-prone and obesity-resistant rats fed standard and hypercaloric diets. Med Sci Monit 2010; 16:BR208-BR217. [PMID: 20581769] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/29/2023] Open
Abstract
BACKGROUND This study tested whether rats with obesity induced by a hypercaloric diet (HD) present higher nutritional, endocrine, and cardiovascular disturbances compared with counterparts with obesity induced by overfeeding of a standard diet. An additional objective was to compare the isolated influence of HD on these parameters in lean and obese rats. MATERIAL/METHODS Twenty Wistar-Kyoto rats were distributed into four groups: CD-lean, CD-obese, HD-lean, and HD-obese. CD (control diet) and HD groups received commercial standard chow and HD, respectively, for 20 weeks. The lean and obese groups included obesity-resistant and obesity-prone animals, respectively. Nutritional and metabolic evaluation involved measurement of calorie intake, dietary efficiency, body weight, adiposity, glycemia, triacylglycerol, insulin, and leptin. Cardiovascular evaluation included systolic blood pressure measurement, echocardiography, and analyses of myocardial morphology and myosin heavy-chain composition. RESULTS In both diets, obesity was characterized by increased adiposity, hyperleptinemia, hypertriacylglycerolemia, hyperinsulinemia, and cardiomyocyte nuclear hypertrophy. HD promoted hyperleptinemia and cardiac remodeling, characterized by nuclear and ventricular hypertrophy, as well as improved systolic performance in both the obesity-prone and obesity-resistant biotypes. In contrast to HD-lean, HD-obese rats presented more accentuated endocrine responses, including hyperglycemia, lower glycemic tolerance, and hyperleptinemia as well as interstitial fibrosis compared with the CD-obese animals. CONCLUSIONS This study confirmed the primary hypothesis that rats with HD-induced obesity present more accentuated nutritional and endocrine disturbances compared with their counterparts with obesity resulting from overfeeding. In addition, dietary effects were more important between the obese groups, supporting evidence of an interaction between diet and biotype.
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Affiliation(s)
- Silvio A Oliveira Junior
- Internal Medicine Department, Botucatu Medical School, São Paulo State University, Botucatu, Brazil.
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Santos DPD, Okoshi K, Moreira VO, Seiva FRF, Almeida FLAD, Padovani CR, Carvalho RF, Okoshi MP, Cicogna AC, Castro AVB, Pai-Silva MD. Growth hormone attenuates skeletal muscle changes in experimental chronic heart failure. Growth Horm IGF Res 2010; 20:149-155. [PMID: 20060348 DOI: 10.1016/j.ghir.2009.11.007] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/26/2009] [Revised: 11/20/2009] [Accepted: 11/30/2009] [Indexed: 12/30/2022]
Abstract
OBJECTIVE This study evaluated the effects of growth hormone (GH) on morphology and myogenic regulatory factors (MRF) gene expression in skeletal muscle of rats with ascending aortic stenosis (AAS) induced chronic heart failure. DESIGN Male 90-100g Wistar rats were subjected to thoracotomy. AAS was created by placing a stainless-steel clip on the ascending aorta. Twenty five weeks after surgery, rats were treated with daily subcutaneous injections of recombinant human GH (2mg/kg/day; AAS-GH group) or saline (AAS group) for 14 days. Sham-operated animals served as controls. Left ventricular (LV) function was assessed before and after treatment. IGF-1 serum levels were measured by ELISA. After anesthesia, soleus muscle was frozen in liquid nitrogen. Histological sections were stained with HE and picrosirius red to calculate muscle fiber cross-sectional area and collagen fractional area, respectively. MRF myogenin and MyoD expression was analyzed by reverse transcription PCR. RESULTS Body weight was similar between groups. AAS and AAS-GH groups presented dilated left atrium, left ventricular (LV) hypertrophy (LV mass index: Control 1.90+/-0.15; AAS 3.11+/-0.44; AAS-GH 2.94+/-0.47 g/kg; p<0.05 AAS and AAS-GH vs. Control), and reduced LV posterior wall shortening velocity. Soleus muscle fiber area was significantly lower in AAS than in Control and AAS-GH groups; there was no difference between AAS-GH and Control groups. Collagen fractional area was significantly higher in AAS than Control; AAS-GH did not differ from both Control and AAS groups. Serum IGF-1 levels decreased in AAS compared to Control. MyoD mRNA was significantly higher in AAS-GH than AAS; there was no difference between AAS-GH and Control groups. Myogenin mRNA levels were similar between groups. CONCLUSION In rats with aortic stenosis-induced heart failure, growth hormone administration increases MyoD gene expression above non-treated animal levels, preserves muscular trophism and attenuates interstitial fibrosis. These results suggest that growth hormone may have a potential role as an adjuvant therapy for chronic heart failure.
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Affiliation(s)
- Denis Pioli dos Santos
- Department of Morphology, Bioscience Institute, São Paulo State University, Botucatu, São Paulo, Brazil
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Carvalho RF, Castan EP, Coelho CA, Lopes FS, Almeida FLA, Michelin A, de Souza RWA, Araújo JP, Cicogna AC, Dal Pai-Silva M. Heart failure increases atrogin-1 and MuRF1 gene expression in skeletal muscle with fiber type-specific atrophy. J Mol Histol 2010; 41:81-7. [PMID: 20349269 DOI: 10.1007/s10735-010-9262-x] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2010] [Accepted: 03/10/2010] [Indexed: 01/28/2023]
Abstract
Heart failure (HF) is characterized by a reduced tolerance to exercise due to early fatigue and dyspnea; this may be due in part to skeletal muscle myopathy with a shift from slow to fast fibers and loss of muscle mass. Muscle wasting does not occur similarly in all types of muscle fiber, thus we tested the hypothesis that HF induces skeletal muscle atrophy in a fiber type-specific manner altering the expression of atrogin-1 and MuRF1 in a fast muscle of rats with monocrotaline-induced heart failure. We studied extensor digitorum longus (EDL) muscle from both HF and control Wistar rats. Atrogin-1 and MuRF1 mRNA content were determined using Real-Time RT-qPCR while muscle fiber cross-sectional area (CSA) from sections stained histochemically for myofibrillar ATPase were used as an index of type-specific fiber atrophy. The measurement of gene expression by RT-qPCR revealed that EDL muscle mRNA expression of MuRF1 and atrogin-1 was significantly increased in the HF group. Muscle fiber type IIB CSA decreased in the HF group compared to the CT group; there was no significant difference in muscle fiber types I and IIA/D CSA between the HF and CT groups. In conclusion, we showed that HF induces fiber type IIB specific atrophy, up-regulating atrogin-1 and MuRF1 mRNA expression in EDL muscle of monocrotaline treated rats.
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Affiliation(s)
- Robson Francisco Carvalho
- Department of Morphology, Institute of Biosciences, UNESP São Paulo State University, 18618-000, Botucatu, SP, Brazil.
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Wagner Alves de Souza R, Gonçalves W, Garrido Cavalcante WL, Pai-Silva MD, Gallacci M. Nandrolone stimulates MyoD expression during muscle regeneration in the condition of myonecrosis induced by Bothrops jararacussu venom poisoning. J Toxicol Environ Health A 2010; 73:934-943. [PMID: 20563927 DOI: 10.1080/15287391003751729] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Myonecrosis with permanent loss of muscle mass is a relevant local toxic effect following envenomation with Bothrops jararacussu snake venom. Regeneration of adult skeletal muscle involves the activation of satellite cells, a process regulated by myogenic regulatory factors (MRF). MyoD is an MRF involved in both proliferation and differentiation of satellite cells. Androgens are modulators of skeletal muscle, known to increase muscle mass and strength. This study examined the hypothesis that anabolic androgens improve the muscle regeneration process in mice following envenomation by Bothrops jararacussu snake venom. Myonecrosis was induced by venom injection (30 microg/50 microl in physiological solution) over the extensor digitorum longus (EDL) muscles of mice. Nandrolone (ND) (6 mg/kg, sc) was administered after 12 h, 7 d, and 14 d following venom injection. The histological changes in EDL muscle at 1, 3, 7, and 21 d after muscle injury were analyzed by light microscopy. Cross-sectional areas of fibers were measured. MyoD was evaluated by immunofluorescence technique. Histological examination revealed the presence of a regeneration process in ND-treated animals, characterized by the appearance of some myotubes at 3 d, and numerous myotubes at 7 d from venom injection. Nandrolone treatment reduced the frequency of small fibers at 7 and 21 d after venom administration, and increased the frequency of large fibers at 7 d postinjury. Nandrolone also significantly augmented the expression of MyoD-positive cells at 7 and 21 d after envenomation. These results suggest that ND accelerates muscle regeneration and indicate the involvement of MyoD in this process.
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Lima ARR, Martinez PF, Okoshi K, Guizoni DM, Zornoff LAM, Campos DHS, Oliveira SA, Bonomo C, Pai-Silva MD, Okoshi MP. Myostatin and follistatin expression in skeletal muscles of rats with chronic heart failure. Int J Exp Pathol 2009; 91:54-62. [PMID: 20002838 DOI: 10.1111/j.1365-2613.2009.00683.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
Skeletal muscle abnormalities can contribute to decreased exercise capacity in heart failure. Although muscle atrophy is a common alteration in heart failure, the mechanisms responsible for muscle mass reduction are not clear. Myostatin, a member of TGF-beta family (transforming growth factor), regulates muscle growth and mass. Several studies have shown a negative correlation between myostatin expression and muscle mass. The aim of this study was to evaluate myostatin expression in skeletal muscles of rats with heart failure. As myostatin gene expression can be modulated by follistatin, we also evaluated its expression. Heart failure was induced by myocardial infarction (MI, n = 10); results were compared to Sham-operated group (n = 10). Ventricular function was assessed by echocardiogram. Gene expression was analyzed by real-time PCR and protein levels by Western blotting in the soleus and gastrocnemius muscles; fibre trophism was evaluated by morphometric analysis. MI group presented heart failure evidence such as pleural effusion and right ventricular hypertrophy. Left ventricular dilation and dysfunction were observed in MI group. In the soleus muscle, cross-sectional area (P = 0.006) and follistatin protein levels (Sham 1.00 +/- 0.36; MI 0.18 +/- 0.06 arbitrary units; P = 0.03) were lower in MI and there was a trend for follistatin gene expression to be lower in MI group (P = 0.085). There was no change in myostatin expression between groups. In gastrocnemius, all MI group parameters were statistically similar to the Sham. In conclusion, our data show that during chronic heart failure, decreased skeletal muscle trophism is combined with unchanged myostatin and reduced follistatin expression.
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Affiliation(s)
- Aline Regina Ruiz Lima
- Department of Internal Medicine, Botucatu Medical School, State University of Sao Paulo-UNESP, Botucatu, Sao Paulo, Brazil
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de Freitas CEA, Freitas SDBZ, Lopes FDS, Pai-Silva MD, Piçarro IDC. Skeletal Muscles with Antagonistic Muscular Actions: Morphological, Contractile and Metabolic Characteristics. INT J MORPHOL 2009. [DOI: 10.4067/s0717-95022009000400034] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Gut AL, Sugizaki MM, Okoshi MP, Carvalho RF, Pai-Silva MD, Aragon FF, Padovani CR, Okoshi K, Cicogna AC. Food restriction impairs myocardial inotropic response to calcium and beta-adrenergic stimulation in spontaneously hypertensive rats. Nutr Res 2009; 28:722-7. [PMID: 19083480 DOI: 10.1016/j.nutres.2008.06.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2008] [Revised: 05/27/2008] [Accepted: 06/02/2008] [Indexed: 11/28/2022]
Abstract
Although long-term food restriction (FR) has been shown to induce cardiac remodeling and dysfunction, there are few data on the effects of FR on pressure-overloaded hearts. The aim of this study was to examine the effects of FR on cardiac muscle performance during inotropic stimulation in the myocardium of spontaneously hypertensive rats (SHRs). Male 60-day-old SHRs were subjected to FR for 90 days. Food-restricted animals received 50% of the ad libitum amount of food consumed by the control group. Myocardial function was studied in isolated left ventricular papillary muscle under isometric contraction in basal condition (1.25 mmol/L extracellular Ca(2+) concentration) and after 3 inotropic maneuvers: (1) at postrest contraction of 30 seconds, (2) at extracellular Ca(2+) concentration of 5.2 mmol/L, and (3) after beta-adrenergic stimulation with 10(-6) mol/L isoproterenol. At basal condition, time from peak tension to 50% relaxation was greater in the food-restricted group (P < .05). Inotropic stimulation with postrest contraction and isoproterenol promoted a significant lower increase of developed tension, maximum rate of tension development, and maximum rate of tension decline in the food-restricted compared to the control group. The elevation of extracellular Ca(2+) concentration induced a lower increase of developed tension, maximum rate of tension development, and time from peak tension to 50% relaxation in the food-restricted than in the control group. In conclusion, long-term FR promotes impairment of myocardial inotropic response to calcium and beta-adrenergic stimulation in SHRs.
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Affiliation(s)
- Ana Lucia Gut
- Department of Internal Medicine, School of Medicine, State University Júlio Mesquita Filho (UNESP), Botucatu, São Paulo, Brazil
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15
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Pai-Silva MD, Ueda AK, Resende L, Pai VD, Alves A, Faleiros ATS, De Castro Rodrigues A. Morphological aspects of rabbit masseter muscle after cervical sympathectomy. Int J Exp Pathol 2008. [DOI: 10.1111/j.1365-2613.2001.iep183.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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16
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Lopes FDS, Carvalho RF, Campos GER, Sugizaki MM, Padovani CR, Nogueira CR, Cicogna AC, Pai-Silva MD. Down-regulation of MyoD gene expression in rat diaphragm muscle with heart failure. Int J Exp Pathol 2008; 89:216-22. [PMID: 18460074 DOI: 10.1111/j.1365-2613.2008.00587.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Diaphragm myopathy has been described in patients with heart failure (HF), with alterations in myosin heavy chains (MHC) expression. The pathways that regulate MHC expression during HF have not been described, and myogenic regulatory factors (MRFs) may be involved. The purpose of this investigation was to determine MRF mRNA expression levels in the diaphragm. Diaphragm muscle from both HF and control Wistar rats was studied when overt HF had developed, 22 days after monocrotaline administration. MyoD, myogenin and MRF4 gene expression were determined by RT-PCR and MHC isoforms by polyacrylamide gel electrophoresis. Heart failure animals presented decreased MHC IIa/IIx protein isoform and MyoD gene expression, without altering MHC I, IIb, myogenin and MRF4. Our results show that in HF, MyoD is selectively down-regulated, which might be associated with alterations in MHC IIa/IIx content. These changes are likely to contribute to the diaphragm myopathy caused by HF.
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17
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de Almeida FLA, Carvalho RF, Pinhal D, Padovani CR, Martins C, Dal Pai-Silva M. Differential expression of myogenic regulatory factor MyoD in pacu skeletal muscle (Piaractus mesopotamicus Holmberg 1887: Serrasalminae, Characidae, Teleostei) during juvenile and adult growth phases. Micron 2008; 39:1306-11. [PMID: 18400505 DOI: 10.1016/j.micron.2008.02.011] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2007] [Revised: 02/19/2008] [Accepted: 02/20/2008] [Indexed: 11/27/2022]
Abstract
Skeletal muscle is the edible part of the fish. It grows by hypertrophy and hyperplasia, events regulated by differential expression of myogenic regulatory factors (MRFs). The study of muscle growth mechanisms in fish is very important in fish farming development. Pacu (Piaractus mesopotamicus) is one of the most important food species farmed in Brazil and has been extensively used in Brazilian aquaculture programs. The aim of this study was to analyze hyperplasia and hypertrophy and the MRF MyoD expression pattern in skeletal muscle of pacu (P. mesopotamicus) during juvenile and adult growth stages. Juvenile (n=5) and adult (n=5) fish were anaesthetized, sacrificed, and weight (g) and total length (cm) determined. White dorsal region muscle samples were collected and immersed in liquid nitrogen. Transverse sections (10 microm thick) were stained with Haematoxilin-Eosin (HE) for morphological and morphometric analysis. Smallest fiber diameter from 100 muscle fibers per animal was calculated in each growth phase. These fibers were grouped into three classes (<20, 20-50, and >50 microm) to evaluate hypertrophy and hyperplasia in white skeletal muscle. MyoD gene expression was determined by semi-quantitative RT-PCR. PCR products were cloned and sequenced. Juvenile and adult pacu skeletal muscle had similar morphology. The large number of <20 microm diameter muscle fibers observed in juvenile fish confirms active hyperplasia. In adult fish, most fibers were over 50 microm diameter and denote more intense muscle fiber hypertrophy. The MyoD mRNA level in juveniles was higher than in adults. A consensus partial sequence for MyoD gene (338 base pairs) was obtained. The Pacu MyoD nucleotide sequence displayed high similarity among several vertebrates, including teleosts. The differential MyoD gene expression observed in pacu white muscle is possibly related to differences in growth patterns during the phases analyzed, with hyperplasia predominant in juveniles and hypertrophy in adult fish. These results should provide a foundation for understanding the molecular control of skeletal muscle growth in economically important Brazilian species, with a view to improving production quality.
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Cavalcante W, Santos-Diz-Filho E, Oliveira T, Romero-Vargas F, Ponce-Soto L, Marangoni S, Rodrigues-Simioni L, Dal Pai-Silva M, Gallacci M. Comparison of the neurotoxic effects of venoms and crotoxins from two subspecies of crotalus snakes on mouse neuromuscular junction. Toxicol Lett 2007. [DOI: 10.1016/j.toxlet.2007.05.570] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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19
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Souza R, Gonçalves W, Dal Pai-Silva M, Gallacci M. Influence of anabolic steroid treatment upon muscle regeneration and satellite cells of mice following envenoming by Bothrops jararacussu snake venom. Toxicol Lett 2007. [DOI: 10.1016/j.toxlet.2007.05.596] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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20
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Grassi TF, Pires PW, Barbisan LF, Pai-Silva MD, Said RA, de Camargo JLV. Liver lesions produced by aflatoxins in Rana catesbeiana (bullfrog). Ecotoxicol Environ Saf 2007; 68:71-8. [PMID: 16996133 DOI: 10.1016/j.ecoenv.2006.07.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2006] [Revised: 07/20/2006] [Accepted: 07/28/2006] [Indexed: 05/11/2023]
Abstract
This study describes alterations induced in Rana catesbeiana (bullfrog) liver after extended dietary exposure to aflatoxins (AFs). Bullfrogs of both sexes were fed for 120 days a commercial chow blended with a rice bran-based mixture of AFs containing 667.0, 11.65, 141.74, and 3.53 mg/kg of AFs B1, B2, G1, and G2, respectively. Animals were sacrificed on study days 45, 90, and 120. Severe and progressive liver lesions with structural collapse, increased hepatocyte and biliary duct cell proliferation, appearance of basophilic hepatocytes, and diffuse scarring, were observed at all time points. There were no quantitative alterations in the liver melanomacrophage centers of the AFs-exposed animals. Increased amounts of lipid hydroperoxides, indicative of ongoing oxidative stress, were more evident in the Addutor magnum muscle than in the AFs-damaged livers. No tumors were found in the R. catesbeiana livers after 120 days of exposure to relatively high doses of AFs.
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Affiliation(s)
- Tony Fernando Grassi
- Núcleo de Avaliação do Impacto Ambiental sobre a Saúde Humana (TOXICAM), Faculdade de Medicina, UNESP, Botucatu 18618-000, SP, Brazil
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21
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Cavalcante WLG, Campos TO, Dal Pai-Silva M, Pereira PS, Oliveira CZ, Soares AM, Gallacci M. Neutralization of snake venom phospholipase A2 toxins by aqueous extract of Casearia sylvestris (Flacourtiaceae) in mouse neuromuscular preparation. J Ethnopharmacol 2007; 112:490-7. [PMID: 17540522 DOI: 10.1016/j.jep.2007.04.002] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2006] [Revised: 03/01/2007] [Accepted: 04/15/2007] [Indexed: 05/15/2023]
Abstract
Aqueous extract of Casearia sylvestris (Flacourtiaceae) has been shown to inhibit enzymatic and biological properties of some Bothrops and Crotalus venoms and their purified phospholipase A(2) (PLA(2)) toxins. In this work we evaluated the influence of C. sylvestris aqueous extract upon neuromuscular blocking and muscle damaging activities of some PLA(2)s (crotoxin from C. durissus terrificus, bothropstoxin-I from B. jararacussu, piratoxin-I from B. pirajai and myotoxin-II from B. moojeni) in mouse phrenic-diaphragm preparations. Crotoxin (0.5 microM) and all other PLA(2) toxins (1.0 microM) induced irreversible and time-dependent blockade of twitches. Except for crotoxin, all PLA(2) toxins induced significant muscle damage indices, assessed by microscopic analysis. Preincubation of bothropstoxin-I, piratoxin-I or myotoxin-II with C. sylvestris extract (1:5 (w/w), 30 min, 37 degrees C) significantly prevented the neuromuscular blockade of preparations exposed to the mixtures for 90 min; the extent of protection ranged from 93% to 97%. The vegetal extract also neutralized the muscle damage (protection of 80-95%). Higher concentration of the C. sylvestris extract (1:10, w/w) was necessary to neutralize by 90% the neuromuscular blockade induced by crotoxin. These findings expanded the spectrum of C. sylvestris antivenom activities, evidencing that it may be a good source of potentially useful PLA(2) inhibitors.
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Affiliation(s)
- Walter L G Cavalcante
- Departamento de Farmacologia, Instituto de Biociências, Universidade Estadual Paulista, UNESP, Botucatu, SP, Brazil
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Carvalho RF, Dariolli R, Justulin Junior LA, Sugizaki MM, Politi Okoshi M, Cicogna AC, Felisbino SL, Dal Pai-Silva M. Heart failure alters matrix metalloproteinase gene expression and activity in rat skeletal muscle. Int J Exp Pathol 2007; 87:437-43. [PMID: 17222211 PMCID: PMC2517391 DOI: 10.1111/j.1365-2613.2006.00497.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Heart failure is associated with a skeletal muscle myopathy with cellular and extracellular alterations. The hypothesis of this investigation is that extracellular changes may be associated with enhanced mRNA expression and activity of matrix metalloproteinases (MMP). We examined MMP mRNA expression and MMP activity in Soleus (SOL), extensor digitorum longus (EDL), and diaphragm (DIA) muscles of young Wistar rat with monocrotaline-induced heart failure. Rats injected with saline served as age-matched controls. MMP2 and MMP9 mRNA contents were determined by RT-PCR and MMP activity by electrophoresis in gelatin-containing polyacrylamide gels in the presence of SDS under non-reducing conditions. Heart failure increased MMP9 mRNA expression and activity in SOL, EDL and DIA and MMP2 mRNA expression in DIA. These results suggest that MMP changes may contribute to the skeletal muscle myopathy during heart failure.
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Okoshi MP, Okoshi K, Matsubara LS, Dal Pai-Silva M, Gut AL, Padovani CR, Dal Pai V, Cicogna AC. Myocardial remodeling and dysfunction are induced by chronic food restriction in spontaneously hypertensive rats. Nutr Res 2006. [DOI: 10.1016/j.nutres.2006.09.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Sugizaki MM, Dal Pai-Silva M, Carvalho RF, Padovani CR, Bruno A, Nascimento AF, Aragon FF, Novelli ELB, Cicogna AC. Exercise training increases myocardial inotropic response in food restricted rats. Int J Cardiol 2006; 112:191-201. [PMID: 16356569 DOI: 10.1016/j.ijcard.2005.08.039] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/05/2005] [Revised: 08/24/2005] [Accepted: 08/29/2005] [Indexed: 11/20/2022]
Abstract
This study evaluated the effects of exercise training on myocardial function and ultrastructure of rats submitted to different levels of food restriction (FR). Male Wistar-Kyoto rats, 60 days old, were submitted to free access to food, light FR (20%), severe FR (50%) and/or to swimming training (one hour per day with 5% of load, five days per week for 90 days). Myocardial function was evaluated by left ventricular papillary muscle under basal condition (calcium 1.25 mM), and after extracellular calcium elevation to 5.2 mM and isoproterenol (1 microM) addition. The ultrastructure of the myocardium was examined in the papillary muscle. The training effectiveness was verified by improvement of myocardial metabolic enzyme activities. Both 20% and 50% food restriction protocols presented minor body and ventricular weights gain. The 20%-FR, in sedentary or trained rats, did not alter myocardial function or ultrastructure. The 50%-FR, in sedentary rats, caused myocardial dysfunction under basal condition, decreased response to inotropic stimulation, and promoted myocardial ultrastructural damage. The 50%-FR, in exercised rats, increased myocardial dysfunction under basal condition but increased response to inotropic stimulation although there was myocardial ultrastructural damage. In conclusion, the exercise training in severe restriction caused marked myocardial dysfunction at basal condition but increased myocardial response to inotropic stimulation.
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Affiliation(s)
- Mario Mateus Sugizaki
- Department of Internal Medicine, School of Medicine, State University Júlio, Mesquita Filho, UNESP, Botucatu, São Paulo, Brazil
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25
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Carvalho RF, Cicogna AC, Campos GER, da Silva Lopes F, Sugizaki MM, Nogueira CR, Pai-Silva MD. Heart failure alters MyoD and MRF4 expressions in rat skeletal muscle. Int J Exp Pathol 2006; 87:219-25. [PMID: 16709230 PMCID: PMC2517363 DOI: 10.1111/j.1365-2613.2006.00475.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Heart failure (HF) is characterized by a skeletal muscle myopathy with increased expression of fast myosin heavy chains (MHCs). The skeletal muscle-specific molecular regulatory mechanisms controlling MHC expression during HF have not been described. Myogenic regulatory factors (MRFs), a family of transcriptional factors that control the expression of several skeletal muscle-specific genes, may be related to these alterations. This investigation was undertaken in order to examine potential relationships between MRF mRNA expression and MHC protein isoforms in Wistar rat skeletal muscle with monocrotaline-induced HF. We studied soleus (Sol) and extensor digitorum longus (EDL) muscles from both HF and control Wistar rats. MyoD, myogenin and MRF4 contents were determined using reverse transcription-polymerase chain reaction while MHC isoforms were separated using polyacrylamide gel electrophoresis. Despite no change in MHC composition of Wistar rat skeletal muscles with HF, the mRNA relative expression of MyoD in Sol and EDL muscles and that of MRF4 in Sol muscle were significantly reduced, whereas myogenin was not changed in both muscles. This down-regulation in the mRNA relative expression of MRF4 in Sol was associated with atrophy in response to HF while these alterations were not present in EDL muscle. Taken together, our results show a potential role for MRFs in skeletal muscle myopathy during HF.
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Affiliation(s)
- Robson Francisco Carvalho
- Departamento de Morfologia, UNESP, BotucatuSão Paulo, Brazil
- Departamentos de Biologia Celular e Anatomia, UNICAMP, CampinasSão Paulo, Brazil
| | | | | | - Francis da Silva Lopes
- Departamentos de Biologia Celular e Anatomia, UNICAMP, CampinasSão Paulo, Brazil
- Departamento de Fisioterapia, UNOESTE, Presidente PrudenteBrazil
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Gallacci M, Oliveira M, Dal Pai-Silva M, Cavalcante WLG, Spencer PJ. Paralyzing and myotoxic effects of a recombinant bothropstoxin-I (BthTX-I) on mouse neuromuscular preparations. ACTA ACUST UNITED AC 2006; 57:239-45. [PMID: 16410190 DOI: 10.1016/j.etp.2005.09.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2004] [Accepted: 09/01/2005] [Indexed: 11/18/2022]
Abstract
As a first step to investigate the structure-function relationship of bothropstoxin-I (BthTX-I), a myotoxin from Bothrops jararacussu snake venom, our group previously cloned a recombinant toxin (rBthTX-I) in Escherichia coli. The aim of this work was to characterize the biological activities of this rBthTX-I (1.0 microM) in both phrenic-diaphragm and extensor digitorum longus preparations in vitro, by means of myographic and morphologic techniques. Native BthTX-I (1.0 microM) was used as a standard. The influence of heparin (27.5 microg/ml) upon the biological activities of both toxins was also investigated. rBthTX-I had similar effects to the native toxin inducing blockage of both directly and indirectly evoked contractions in phrenic-diaphragm preparations, and muscle damage characterized by edema, round fibers, and cell areas devoid of myofibrils. Interestingly the paralyzing activity of rBthTX-I was slightly more potent than the native toxin. Heparin prevented paralyzing and myotoxic effects of both the native and recombinant toxins. This work shows that rBthTX-I was expressed in a fully active form, and presents a biological profile similar to the native toxin.
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Affiliation(s)
- Márcia Gallacci
- Departamento de Farmacologia, Instituto de Biociências, Universidade Estadual Paulista, Rubião Júnior, Botucatu, CEP 18618-000, São Paulo, Brazil.
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Zornoff LAM, Matsubara LS, Matsubara BB, Okoshi MP, Okoshi K, Dal Pai-Silva M, Carvalho RF, Cicogna AC, Padovani CR, Novelli EL, Novo R, Campana AO, Paiva SAR. Beta-Carotene Supplementation Attenuates Cardiac Remodeling Induced by One-Month Tobacco-Smoke Exposure in Rats. Toxicol Sci 2005; 90:259-66. [PMID: 16387745 DOI: 10.1093/toxsci/kfj080] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
OBJECTIVE The objectives were to analyze the cardiac effects of exposure to tobacco smoke (ETS), for a period of 30 days, alone and in combination with beta-carotene supplementation (BC). RESEARCH METHODS AND PROCEDURES Rats were allocated into: Air (control, n = 13); Air + BC (n = 11); ETS (n = 11); and BC + ETS (n = 9). In Air + BC and BC + ETS, 500 mg of BC were added to the diet. After three months of randomization, cardiac structure and function were assessed by echocardiogram. After that, animals were euthanized and morphological data were analyzed post-mortem. One-way and two-way ANOVA were used to assess the effects of ETS, BC and the interaction between ETS and BC on the variables. RESULTS ETS presented smaller cardiac output (0.087 +/- 0.001 vs. 0.105 +/- 0.004 l/min; p = 0.007), higher left ventricular diastolic diameter (19.6 +/- 0.5 vs. 18.0 +/- 0.5 mm/kg; p = 0.024), higher left ventricular (2.02 +/- 0.05 vs. 1.70 +/- 0.03 g/kg; p < 0.001) and atrium (0.24 +/- 0.01 vs. 0.19 +/- 0.01 g/kg; p = 0.003) weight, adjusted to body weight of animals, and higher values of hepatic lipid hydroperoxide (5.32 +/- 0.1 vs. 4.84 +/- 0.1 nmol/g tissue; p = 0.031) than Air. However, considering those variables, there were no differences between Air and BC + ETS (0.099 +/- 0.004 l/min; 19.0 +/- 0.5 mm/kg; 1.83 +/- 0.04 g/kg; 0.19 +/- 0.01 g/kg; 4.88 +/- 0.1 nmol/g tissue, respectively; p > 0.05). Ultrastructural alterations were found in ETS: disorganization or loss of myofilaments, plasmatic membrane infolding, sarcoplasm reticulum dilatation, polymorphic mitochondria with swelling and decreased cristae. In BC + ETS, most fibers showed normal morphological aspects. CONCLUSION One-month tobacco-smoke exposure induces functional and morphological cardiac alterations and BC supplementation attenuates this ventricular remodeling process.
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Affiliation(s)
- Leonardo A M Zornoff
- Departamento de Clínica Médica, Faculdade de Medicina de Botucatu, Universidade Estadual Paulista (UNESP), Botucatu, Brazil.
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28
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Sugizaki MM, Carvalho RF, Aragon FF, Padovani CR, Okoshi K, Okoshi MP, Zanati SG, Pai-Silva MD, Novelli ELB, Cicogna AC. Myocardial dysfunction induced by food restriction is related to morphological damage in normotensive middle-aged rats. J Biomed Sci 2005; 12:641-9. [PMID: 16132105 DOI: 10.1007/s11373-005-7652-y] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2004] [Accepted: 04/18/2005] [Indexed: 10/25/2022] Open
Abstract
Previous works from our laboratory have revealed that food restriction (FR) promotes discrete myocardial dysfunction in young rats. We examined the effects of FR on cardiac function, in vivo and in vitro, and ultrastructural changes in the heart of middle-aged rats. Twelve-month-old Wistar-Kyoto rats were fed a control (C) or restricted diet (daily intake reduced to 50% of the control group) for 90 days. Cardiac performance was studied by echocardiogram and in isolated left ventricular (LV) papillary muscle by isometric contraction in basal condition, after calcium chloride (5.2 mM) and beta-adrenergic stimulation with isoproterenol (10(-6) M). FR did not change left ventricular function, but increased time to peak tension, and decreased maximum rate of papillary muscle tension development. Inotropic maneuvers promoted similar effects in both groups. Ultrastructural alterations were seen in most FR rat muscle fibers and included, absence and/or disorganization of myofilaments and Z line, hyper-contracted myofibrils, polymorphic and swollen mitochondria with disorganized cristae, and a great quantity of collagen fibrils. In conclusion, cardiac muscle sensitivity to isoproterenol and elevation of extracellular calcium concentration is preserved in middle-aged FR rats. The intrinsic muscle performance depression might be related to morphological damage.
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Affiliation(s)
- Mario Mateus Sugizaki
- Department of Internal Medicine- School of Medicine, Faculdade de Medicina de Botucatu, UNESP, Rubião Júnior, S/N, 18618-000, Botucatu, SP, Brazil
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Navas CA, Antoniazzi MM, Carvalho JE, Chaui-Berlink JG, James RS, Jared C, Kohlsdorf T, Pai-Silva MD, Wilson RS. Morphological and physiological specialization for digging in amphisbaenians, an ancient lineage of fossorial vertebrates. ACTA ACUST UNITED AC 2004; 207:2433-41. [PMID: 15184515 DOI: 10.1242/jeb.01041] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Amphisbaenians are legless reptiles that differ significantly from other vertebrate lineages. Most species dig underground galleries of similar diameter to that of the animal. We studied the muscle physiology and morphological attributes of digging effort in the Brazilian amphisbaenid Leposternon microcephalum (Squamata; Amphisbaenia), which burrows by compressing soil against the upper wall of the tunnel by means of upward strokes of the head. The individuals tested (<72 g) exerted forces on the soil of up to 24 N. These forces were possible because the fibres of the longissimus dorsi, the main muscle associated with burrowing, are highly pennated, thus increasing effective muscle cross-sectional area. The muscle is characterized by a metabolic transition along its length: proximal, medial and distal fibres are fast contracting and moderately oxidative, but fibres closer to the head are richer in citrate synthase and more aerobic in nature. Distal fibres, then, might be active mainly at the final step of the compression stroke, which requires more power. For animals greater than a given diameter, the work required to compress soil increases exponentially with body diameter. Leposternon microcephalum, and probably some other highly specialized amphisbaenids, are most likely constrained to small diameters and can increase muscle mass and effective muscle cross-sectional area by increasing body length, not body diameter.
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Affiliation(s)
- Carlos A Navas
- Departamento de Fisiologia, Instituto de Biociências, Universidade de São Paulo, Rua do Matão Travessa 14 No. 321, CEP 05508-900, SP, Brazil.
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Kohlsdorf T, James RS, Carvalho JE, Wilson RS, Dal Pai-Silva M, Navas CA. Locomotor performance of closely related Tropidurus species: relationships with physiological parameters and ecological divergence. ACTA ACUST UNITED AC 2004; 207:1183-92. [PMID: 14978059 DOI: 10.1242/jeb.00870] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Tropidurid lizards have colonized a variety of Brazilian open environments without remarkable morphological variation, despite ecological and structural differences among habitats used. This study focuses on two Tropidurus sister-species that, despite systematic proximity and similar morphology, exhibit great ecological divergence and a third ecologically generalist congeneric species providing an outgroup comparison. We quantified jumping capacity and sprint speed of each species on sand and rock to test whether ecological divergence was also accompanied by differences in locomotor performance. Relevant physiological traits possibly associated with locomotor performance - metabolic scopes and fiber type composition, power output and activity of the enzymes citrate synthase, pyruvate kinase and lactate dehydrogenase of the iliofibularis muscle - were also compared among the three Tropidurus species. We found that the two sister-species exhibited remarkable differences in jumping performance, while Tropidurus oreadicus, the more distantly related species, exhibited intermediate values. Tropidurus psamonastes, a species endemic to sand dunes, exhibited high absolute sprint speeds on sand, jumped rarely and possessed a high proportion of glycolytic fibers and low activity of citrate synthase. The sister-species Tropidurus itambere, endemic to rocky outcrops, performed a large number of jumps and achieved lower absolute sprint speed than T. psamonastes. This study provides evidence of rapid divergence of locomotor parameters between sister-species that use different substrates, which is only partially explained by variation in physiological parameters of the iliofibularis muscle.
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Affiliation(s)
- Tiana Kohlsdorf
- Departamento de Fisiologia, Instituto de Biociências, Universidade de São Paulo, Rua do Matão, Travessa 14, No. 321, 05508-900, São Paulo, SP, Brazil
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Carvalho RF, Cicogna AC, Campos GER, De Assis JMF, Padovani CR, Okoshi MP, Pai-Silva MD. Myosin heavy chain expression and atrophy in rat skeletal muscle during transition from cardiac hypertrophy to heart failure. Int J Exp Pathol 2003; 84:201-6. [PMID: 14632634 PMCID: PMC2517558 DOI: 10.1046/j.1365-2613.2003.00351.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
The purpose of this investigation was to determine whether changes in myosin heavy chain (MHC) expression and atrophy in rat skeletal muscle are observed during transition from cardiac hypertrophy to chronic heart failure (CHF) induced by aortic stenosis (AS). AS and control animals were studied 12 and 18 weeks after surgery and when overt CHF had developed in AS animals, 28 weeks after the surgery. The following parameters were studied in the soleus muscle: muscle atrophy index (soleus weight/body weight), muscle fibre diameter and frequency and MHC expression. AS animals presented decreases in both MHC1 and type I fibres and increases in both MHC2a and type IIa fibres during late cardiac hypertrophy and CHF. Type IIa fibre atrophy occurred during CHF. In conclusion, our data demonstrate that skeletal muscle phenotype changes occur in both late cardiac hypertrophy and heart failure; this suggests that attention should be given to the fact that skeletal muscle phenotype changes occur prior to overt heart failure symptoms.
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Affiliation(s)
- Robson Francisco Carvalho
- Departamento de Morfologia, UNESPBotucatu, São Paulo, Brazil
- Departamento de Biologia Celular, UNICAMPCampinas, São Paulo, Brazil
| | | | | | - Jeane Marlene Fogaça De Assis
- Departamento de Morfologia, UNESPBotucatu, São Paulo, Brazil
- Departamento de Biologia Celular, UNICAMPCampinas, São Paulo, Brazil
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Souza FAD, Spencer PJ, Rogero JR, Nascimento N, Dal Pai-Silva M, Gallacci M. 60Co gamma irradiation prevents Bothrops jararacussu venom neurotoxicity and myotoxicity in isolated mouse neuromuscular junction. Toxicon 2002; 40:1101-106. [PMID: 12165311 DOI: 10.1016/s0041-0101(02)00103-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The ability of gamma radiation from 60Co (2000 Gy) to attenuate the toxic effects of Bothrops jararacussu venom was investigated on mouse neuromuscular preparations in vitro. A comparative study between the effects of native and irradiated venoms was performed on both phrenic--diaphragm (PD) and extensor digitorum longus (EDL) preparations by means of myographic, biochemical and morphological techniques. Native venom (10 and 20 micro g/ml) induced a concentration--dependent paralysis of both directly and indirectly evoked contractions on PD preparations. At 20 micro g /ml, it also caused a pronounced myotoxic effect on the EDL muscle preparation that was characterized by an increase of creatine kinase release and by several morphological changes of this preparation. By contrast, irradiated venom, even at concentrations as high as 40 micro g/ml, induced neither paralyzing nor myotoxic effects. It was concluded that 60Co gamma radiation is able to abolish both the paralyzing and the myotoxic effects of B. jararacussu venom on the mouse neuromuscular junction. These findings support the hypothesis that gamma radiation could be an important tool to improve antisera production by reducing toxicity while preserving immunogenicity.
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Affiliation(s)
- Fábio A D Souza
- Departamento de Farmacologia, Instituto de Biociências, Universidade Estadual Paulista, Rubião Júnior, Botucatu, CEP 18618-000, São Paulo, Brazil
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Okoshi MP, Okoshi K, Pai VD, Pai-Silva MD, Matsubara LS, Cicogna AC. Mechanical, biochemical, and morphological changes in the heart from chronic food-restricted rats. Can J Physiol Pharmacol 2001. [DOI: 10.1139/y01-060] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Food restriction (FR) has been shown to induce important morphological changes in rat myocardium. However, its influence on myocardial performance is not completely defined. We examined the effects of chronic FR on cardiac muscle function and morphology. Sixty-day-old WistarKyoto rats were fed a control (C) or a restricted diet (daily intake reduced to 50% of the amount of food consumed by the control group) for 90 days. Myocardial performance was studied in isolated left ventricular (LV) papillary muscle. Fragments of the LV free wall were analysed by light microscopy, and the ultrastructure of the myocardium was examined in t...he LV papillary muscle. The myocardial collagen concentration was also evaluated. FR decreased body weight (BW) and LV weight (LVW); the LVW/BW ratio was higher in the restricted group (C, 1.86 ± 0.17 mg/g; FR, 2.19 ± 0.31 mg/g; p < 0.01). In the FR animals, the cardiac fibers were polymorphic, some of them were of small diameter and others presented lateral infoldings; the ultrastructural alterations were focal and included reduction of sarcoplasmic content, absence and (or) disorganization of myofilaments and Z line, numerous electron dense and polymorphic mitochondria, and deep infoldings of the plasma membrane. The hydroxyproline concentration was higher in the FR animals (p < 0.01). FR prolonged the contraction and relaxation time of the papillary muscle and did not change its ability to contract and shorten. In conclusion, although a 90-day period of FR caused striking myocardial ultrastructural alterations and increased the collagen concentration, it only minimally affected the mechanical function.Key words: diet, papillary muscle, undernutrition, myocardium, ultrastructure.
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Okoshi MP, Okoshi K, Pai VD, Pai-Silva MD, Matsubara LS, Cicogna AC. Mechanical, biochemical, and morphological changes in the heart from chronic food-restricted rats. Can J Physiol Pharmacol 2001; 79:754-60. [PMID: 11599775] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
Food restriction (FR) has been shown to induce important morphological changes in rat myocardium. However, its influence on myocardial performance is not completely defined. We examined the effects of chronic FR on cardiac muscle function and morphology. Sixty-day-old Wistar-Kyoto rats were fed a control (C) or a restricted diet (daily intake reduced to 50% of the amount of food consumed by the control group) for 90 days. Myocardial performance was studied in isolated left ventricular (LV) papillary muscle. Fragments of the LV free wall were analysed by light microscopy, and the ultrastructure of the myocardium was examined in the LV papillary muscle. The myocardial collagen concentration was also evaluated. FR decreased body weight (BW) and LV weight (LVW); the LVW/BW ratio was higher in the restricted group (C, 1.86+/-0.17 mg/g; FR, 2.19+/-0.31 mg/g; p < 0.01). In the FR animals, the cardiac fibers were polymorphic, some of them were of small diameter and others presented lateral infoldings; the ultrastructural alterations were focal and included reduction of sarcoplasmic content, absence and (or) disorganization of myofilaments and Z line, numerous electron dense and polymorphic mitochondria, and deep infoldings of the plasma membrane. The hydroxyproline concentration was higher in the FR animals (p < 0.01). FR prolonged the contraction and relaxation time of the papillary muscle and did not change its ability to contract and shorten. In conclusion, although a 90-day period of FR caused striking myocardial ultrastructural alterations and increased the collagen concentration, it only minimally affected the mechanical function.
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Affiliation(s)
- M P Okoshi
- Departamento de Clínica Médica, Faculdade de Medicina de Botucatu, UNESP, São Paulo, Brasil
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Pai-Silva MD, Ueda AK, Resende LA, Pai VD, Alves A, Faleiros AT, De Castro Rodrigues A. Morphological aspects of rabbit masseter muscle after cervical sympathectomy. Int J Exp Pathol 2001; 82:123-8. [PMID: 11454103 PMCID: PMC2517706 DOI: 10.1111/j.1365-2613.2001.iep0082-0123-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
The objective of this paper was to study the effect of sympathetic innervation on morphological and histochemical aspects of skeletal muscle tissue. Rabbit masseter muscle was studied using histochemical and immunohistochemical methods for periods of up to 18 months post-sympathectomy. The morphological and enzymatic characteristics of control masseter muscles were similar on both the left and right sides. The main features were muscle fibres with a mosaic pattern and a predominance of type IIa fibres, followed by type I. Type IIb fibres showed very low frequency. Sympathectomized animals showed varying degrees of metabolic and morphological alterations, especially 18 months after sympathectomy. The first five groups showed a higher frequency of type I fibres, whilst the oldest group showed a higher frequency of type IIb fibres. In the oldest group, a significant variation in fibre diameter was observed. Many fibres showed small diameter, atrophy, hypertrophy, splitting, and necrosis. Areas with fibrosis were observed. Thus cervical sympathectomy induced morphological alterations in the masseter muscles. These alterations were, in part, similar to both denervation and myopathy. These findings indicate that sympathetic innervation contributes to the maintenance of the morphological and metabolic features of masseter muscle fibres.
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Affiliation(s)
- M D Pai-Silva
- Department of Morphology, UNESP Botucatu, São Paulo, Brazil.
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Dal Pai V, Pai-Silva MD, Carvalho ED, Fujihara CY, Gregório EA, Curi PR. Morphological, histochemical and morphometric study of the myotomal muscle tissue of the pacu (Piaractus mesopotamicus Holmberg 1887: Serrasalminae, Characidae, Teleostei). Anat Histol Embryol 2000; 29:283-9. [PMID: 11103517 DOI: 10.1046/j.1439-0264.2000.00273.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Histochemical, ultrastructural and morphometric methods were used to study growth patterns of red, pink and white muscle fibres and their relation to body weight and total length in the fast-growing freshwater fish Piaractus mesopotamicus Holmberg. The correlations amongst body weight, body length and diameter of red, pink and white fibres were low. From 10-15 to 40-50 cm, body weight increased 102.7 times, while the diameter of each type of fibre increased by factors of 0.94, 0.74 and 0.70, respectively. Muscle fibres revealed different morphological and histochemical stages of maturation. The frequencies of < 20 microns fibres of red, pink and white muscle tissue in the youngest and oldest classes were 64.5 and 11.0, 38.2 and 7.7 and 24.0 and 1.4%, respectively. In 30-40 cm fish, the frequency of < 20 microns fibres in the red and pink tissue was 24.5 and 25.5%, while in the white tissue it was 11.5%. During sexual maturity (40-50 cm), the recruitment of < 20 microns fibres in white muscle was 1.4%. Muscle fibres of this species showed continuous growth by both hyperplastic and hypertrophic mechanisms, and hyperplasia was particularly active in the juvenile phase.
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Affiliation(s)
- V Dal Pai
- Department of Morphology, São Paulo State University (UNESP), Botucatu, Brazil
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