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1.
Front Cell Neurosci ; 18: 1413843, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39109218

RESUMO

Multiple sclerosis is a chronic inflammatory disease of the central nervous system characterized by autoimmune destruction of the myelin sheath, leading to irreversible and progressive functional deficits in patients. Pre-clinical studies involving the use of neural stem cells (NSCs) have already demonstrated their potential in neuronal regeneration and remyelination. However, the exclusive application of cell therapy has not proved sufficient to achieve satisfactory therapeutic levels. Recognizing these limitations, there is a need to combine cell therapy with other adjuvant protocols. In this context, extracellular vesicles (EVs) can contribute to intercellular communication, stimulating the production of proteins and lipids associated with remyelination and providing trophic support to axons. This study aimed to evaluate the therapeutic efficacy of the combination of NSCs and EVs derived from oligodendrocyte precursor cells (OPCs) in an animal model of multiple sclerosis. OPCs were differentiated from NSCs and had their identity confirmed by gene expression analysis and immunocytochemistry. Exosomes were isolated by differential ultracentrifugation and characterized by Western, transmission electron microscopy and nanoparticle tracking analysis. Experimental therapy of C57BL/6 mice induced with experimental autoimmune encephalomyelitis (EAE) were grouped in control, treated with NSCs, treated with OPC-derived EVs and treated with a combination of both. The treatments were evaluated clinically using scores and body weight, microscopically using immunohistochemistry and immunological profile by flow cytometry. The animals showed significant clinical improvement and weight gain with the treatments. However, only the treatments involving EVs led to immune modulation, changing the profile from Th1 to Th2 lymphocytes. Fifteen days after treatment revealed a reduction in reactive microgliosis and astrogliosis in the groups treated with EVs. However, there was no reduction in demyelination. The results indicate the potential therapeutic use of OPC-derived EVs to attenuate inflammation and promote recovery in EAE, especially when combined with cell therapy.

2.
Microsc Res Tech ; 87(8): 1733-1741, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38501548

RESUMO

The peripheral nerve injury (PNI) affects the morphology of the whole locomotor apparatus, which can reach the myotendinous junction (MTJ) interface. In the injury condition, the skeletal muscle satellite cells (SC) are triggered, activated, and proliferated to repair their structure, and in the MTJ, the telocytes (TC) are associated to support the interface with the need for remodeling; in that way, these cells can be associated with SC. The study aimed to describe the SC and TC relationship after PNI at the MTJ. Sixteen adult Wistar rats were divided into Control Group (C, n = 8) and PNI Group (PNI, n = 8), PNI was performed by the constriction of the sciatic nerve. The samples were processed for transmission electron microscopy and immunostaining analysis. In the C group was evidenced the arrangement of sarcoplasmic evaginations and invaginations, the support collagen layer with a TC inside it, and an SC through vesicles internally and externally to then. In the PNI group were observed the disarrangement of invaginations and evaginations and sarcomeres degradation at MTJ, as the disposition of telopodes adjacent and in contact to the SC with extracellular vesicles and exosomes in a characterized paracrine activity. These findings can determine a link between the TCs and the SCs at the MTJ remodeling. RESEARCH HIGHLIGHTS: Peripheral nerve injury promotes the myotendinous junction (MTJ) remodeling. The telocytes (TC) and the satellite cells (SC) are present at the myotendinous interface. TC mediated the SC activity at MTJ.


Assuntos
Vesículas Extracelulares , Microscopia Eletrônica de Transmissão , Ratos Wistar , Células Satélites de Músculo Esquelético , Telócitos , Animais , Telócitos/fisiologia , Telócitos/ultraestrutura , Células Satélites de Músculo Esquelético/fisiologia , Células Satélites de Músculo Esquelético/citologia , Ratos , Vesículas Extracelulares/ultraestrutura , Vesículas Extracelulares/metabolismo , Traumatismos dos Nervos Periféricos/patologia , Traumatismos dos Nervos Periféricos/metabolismo , Masculino , Nervo Isquiático/ultraestrutura , Tendões/fisiologia , Músculo Esquelético/ultraestrutura , Junção Miotendínea
3.
Microsc Microanal ; : 1-8, 2022 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-35659819

RESUMO

The tongue is a fundamental organ in feeding, vocalization, and grooming. It is characterized by evolutionary adaptations reflected by diet, habitat, and function. Rodents are a very diverse mammalian order and the tongue's morphology varies in size, form, and presence of papillae. This work aimed to describe the morphological and ultrastructural aspects of the tongue of Spix's yellow-toothed cavy (Galea spixii, Wagler, 1831). Tongues of Spix's yellow-toothed cavies were analyzed with light microscopy, scanning, and transmission electron microscopy. The results showed that the tongue was divided into apex, body, and root. There were different types of papillae, such as vallate, foliate, laterally placed fungiform, fungiform, filiform, and robust filiform. The epithelium was organized into layers, including keratinized, granulous, spinous, and basal, below were lamina propria, and musculature, which evolved mucous and serous gland clusters. The tongue of Spix's yellow-toothed cavy was structurally and ultrastructurally similar to other rodents and had papillae with similar morphologies to other Caviidae species. However, the presence of robust filiform papillary lines and laterally placed fungiform papillae showed the main differences from other species. This was the first description of the tongue of Spix's yellow-toothed cavy.

4.
Biomedicines ; 10(2)2022 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-35203688

RESUMO

The myotendinous junction (MTJ) is an interface that different stimuli alter their morphology. One of the main stimuli to promote alterations in the MTJ morphology is physical exercise. The present study aimed to investigate the morphology and molecular MTJ adaptations of biceps brachii muscle in adult Wistar rats submitted to different ladder-based protocols. Forty Wistar rats (90 days old) were divided into four groups: Sedentary (S), Climbing (C), Overload Climbing (OC), Climbing, and Overload Climbing (COC). The results of light microscopy demonstrated the cell and collagen tissue reorganization in the experimental groups. The sarcomeres lengths of different regions showed a particular development according to the specific protocols. The sarcoplasmic invaginations and evaginations demonstrated positive increases that promoted the myotendinous interface development. In the extracellular matrix, the structures presented an increase principally in the COC group. Finally, the immunofluorescence analysis showed the telocytes disposition adjacent to the MTJ region in all experimental groups, revealing their network organization. Thus, we concluded that the different protocols contributed to the morphological adaptations with beneficial effects in distinct ways of tissue and cellular development and can be used as a model for MTJ remodeling to future proteomic and genetic analysis.

5.
Tissue Cell ; 75: 101741, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35074725

RESUMO

To investigate the effects of the previous administration of testosterone propionate (TP) on the morphology of the gastrocnemius muscle of Wistar rats submitted to ladder-based resistance training (LRT). Twenty-eight rats were divided equally into groups: initial control (CI), 4-week TP (CT4), 4-week TP + LRT (TRT), and placebo + LRT (RT). The rats from the CT4 and TRT groups were treated with TP for four weeks (10 mg/kg/week). TRT and RT trained for ten weeks. The rodents were euthanized at the end of the experiment, and gastrocnemius muscle, prostate, and left and right testicles were collected. There was no statistical difference between the RT and TRT for final volume load. The prostate mass of the TRT and RT groups was statistically heavier than the CT4 group (P < 0.01). The TRT group's prostate/body mass ratio was statistically different from the CT4 group (P < 0.05). The TRT group was shown to have larger type I, type II, and mean fCSA fibers than all other groups (P < 0.001). Regarding the nuclei/fiber ratio (N/f), the CT4, RT, and TRT groups had higher values than CI (P < 0.01). In addition, the RT group showed a higher N/f ratio than CT4 (P < 0.001) but lower than TRT (P < 0.001). In conclusion, short-term TP administration before resistance training can elicit a greater N/f ratio and size of the mean fCSA of the Gastrocnemius muscle of young adult Wistar rats than resistance training alone.


Assuntos
Treinamento Resistido , Propionato de Testosterona , Animais , Humanos , Hipertrofia , Masculino , Músculo Esquelético , Ratos , Ratos Wistar , Testosterona , Propionato de Testosterona/farmacologia
6.
Exp Brain Res ; 240(3): 887-896, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35075497

RESUMO

The present study aimed to compare the morphological response induced by different ladder-based resistance training (LRT) protocols on the peripheral nerve ultrastructure of young adult Wistar rats. Twenty-nine rodents were distributed into groups: control (CON), submaximal (SUBMAX [6 climbs/session, moderate intensity, 3x/week]) and maximum (MAX [> 4 climbs/session, maximum intensity, 3x/week]) LRT. After 8 weeks, the radial and sciatic nerves were removed and prepared for transmission electron microscopy. In the radial nerve, the myelinated fibers and axons, myelin sheath thickness, and unmyelinated axons were statistically greater in the SUBMAX and MAX. The MAX group had greater unmyelinated fibers than SUBMAX. The Schwann cell (SC) nuclei diameter was statistically larger in the SUBMAX than the CON. The number of microtubules and neurofilaments was statistically higher in the SUBMAX and MAX. In the sciatic nerve, the myelinated fibers, myelinated and unmyelinated axons, and myelin sheath thickness were statistically greater in the SUBMAX and MAX. The SUBMAX and MAX had more SC at the nuclei level than CON. The SC nuclei were statistically larger in the SUBMAX and MAX. The number of microtubules and neurofilaments was statistically higher in the SUBMAX and MAX. Total training load and total load per climb were not different between groups. The SUBMAX and MAX statistically increased maximum carried load (ML). In conclusion, the different LRT protocols induced similar morphological responses in radial and sciatic nerves, probably due to load progression and equal total load volume.


Assuntos
Treinamento Resistido , Animais , Humanos , Bainha de Mielina , Nervo Radial , Ratos , Ratos Wistar , Nervo Isquiático
7.
Microsc Microanal ; : 1-5, 2021 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-34376263

RESUMO

The myotendinous junction (MTJ) is the interface between muscle and tendon, and it is the main area of force transmission of the locomotor apparatus. Dystrophic processes promote pathological injury which affects the skeletal muscle and can influence the morphology of the MTJ. This study aimed to investigate the adaptations in MTJ morphology of mdx mice in the tibialis anterior muscle. Male mice (n = 24) were divided into Control­C57bl/10 and mdx­C57bl/10mdx (Duchenne muscular dystrophy experimental model). In the mdx group, centralized nuclei with a large area and greater deposition of type III collagen (fibrosis) were observed. Also, shorter sarcomeres and sarcoplasmatic projections of MTJ were observed. We concluded that the adaptations in mdx mice demonstrated extensive impairment in the MTJ region with reduced ultrastructures.

8.
Int J Mol Sci ; 22(13)2021 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-34209663

RESUMO

The myotendinous junction (MTJ) is the muscle-tendon interface and constitutes an integrated mechanical unit to force transmission. Joint immobilization promotes muscle atrophy via disuse, while physical exercise can be used as an adaptative stimulus. In this study, we aimed to investigate the components of the MTJ and their adaptations and the associated elements triggered with aquatic training after joint immobilization. Forty-four male Wistar rats were divided into sedentary (SD), aquatic training (AT), immobilization (IM), and immobilization/aquatic training (IMAT) groups. The samples were processed to measure fiber area, nuclear fractal dimension, MTJ nuclear density, identification of telocytes, sarcomeres, and MTJ perimeter length. In the AT group, the maintenance of ultrastructure and elements in the MTJ region were observed; the IM group presented muscle atrophy effects with reduced MTJ perimeter; the IMAT group demonstrated that aquatic training after joint immobilization promotes benefits in the muscle fiber area and fractal dimension, in the MTJ region shows longer sarcomeres and MTJ perimeter. We identified the presence of telocytes in the MTJ region in all experimental groups. We concluded that aquatic training is an effective rehabilitation method after joint immobilization due to reduced muscle atrophy and regeneration effects on MTJ in rats.


Assuntos
Adaptação Fisiológica , Imobilização , Articulações , Condicionamento Físico Animal , Esforço Físico , Tendões/fisiologia , Animais , Masculino , Fibras Musculares Esqueléticas/citologia , Fibras Musculares Esqueléticas/metabolismo , Fibras Musculares Esqueléticas/ultraestrutura , Ratos , Sarcômeros/ultraestrutura , Tendões/citologia , Tendões/ultraestrutura
9.
Exp Brain Res ; 239(8): 2583-2592, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34191117

RESUMO

To analyze the morphological response induced by high-volume, high-intensity ladder-based resistance training (LRT) on the ultrastructure of the radial (forelimb) and sciatic (hindlimb) nerves of adults Wistar rats. Twenty rats were equally distributed into groups: sedentary (SED) and LRT. After the rodents were subjected to the maximum load (ML) carrying test, the LRT group performed 6-8 progressive climbs (2 × 50% ML, 2 × 75% ML, 2 × 100% ML, and 2 × 100% ML + 30 g) three times per week. After 8 weeks, the radial and sciatic nerves were removed and prepared for transmission electron microscopy. In the radial nerve, myelinated axons cross-sectional area (CSA), unmyelinated axons CSA, myelin sheath thickness, and Schwann cells nuclei area were statistically larger in the LRT group than SED (p < 0.05). Also, the number of microtubules and neurofilaments per field were statistically higher in the LRT group than in SED (p < 0.01). For sciatic nerve, myelinated fibers CSA, unmyelinated axons CSA, myelin sheath thickness, Schwann cells nuclei area, and the number of neurofilaments per field were statistically larger in the LRT group compared to the SED group (p < 0.05). LRT with high-volume and high-intensity effectively induce similar changes in adult Wistar rats' radial and sciatic nerves' ultrastructure.


Assuntos
Treinamento Resistido , Animais , Membro Anterior , Membro Posterior , Humanos , Bainha de Mielina , Nervos Periféricos , Ratos , Ratos Wistar , Nervo Isquiático
10.
Microsc Microanal ; : 1-5, 2021 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-33890560

RESUMO

The palate is a fundamental region in food swallowing and presents different adaptations in species. This research aimed to describe structural and ultrastructural characteristics of the palatine epithelium and the connective tissue cores (CTCs) of ten red-rumped agoutis (Dasyprocta leporina­Linnaeus, 1758) using macroscopic, light microscopy, scanning electron microscopy, and transmission electron microscopy. We found nine palatine ridges in the diastema and hard palate, and a smooth surface in the soft palate. Stratified squamous keratinized epithelium with projections of lamina propria and soft palate had gland clusters. Epithelial removal revealed CTCs with a conical shape with high density in the hard palate and the sides of the soft palate. Near the CTCs were nerve fibers in the hard palate, and the soft palate had muscular tissue below the gland clusters. The structural and ultrastructural characteristics enable stability of the hard palate and fixation to the soft palate sides, while the soft palate center has greater mobility thus assisting in food swallowing. We concluded that structural characteristics are similar to other mammals, although the morphology of agouti's palate differs in the amount and disposition of palatine ridges, and the conical CTC's morphology.

11.
Microsc Res Tech ; 84(9): 2017-2023, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33738877

RESUMO

Shark skin is predominantly specialized for swimming and protection, with the dermal denticle being the main structure associated with these abilities. The dermal denticle is a mineral structure with a unique morphology for each species, which allows its use as a taxonomic tool. Few studies have investigated the microscopy aspects of skin and dermal denticles, considering the high diversity of sharks. Here, we investigated the three-dimensional morphoquantitative aspects and mineral composition of dermal denticles in different regions of the angular angel shark, Squatina guggenheim, using scanning electron microscopy and dispersive energy system. With the microscopy, we were able to observe that the dermal denticle morphology changes according to the area it is located. It was possible to describe the dermal denticles individually, from root to the crown, highlighting all of their individualities. Through the dispersive energy system, we showed the proportions of each mineral found in the denticle, by area, demonstrating the composition and the particularities of crown, body, and root, where whitlockite was described for the first time in elasmobranchs. In this way, the present study presented the specificities of the dermal denticles of S. guggenheim, as well sought to understand the different structure functions for the animal, thus assisting future research in animal morphology.


Assuntos
Calcificações da Polpa Dentária , Tubarões , Animais , Microscopia Eletrônica de Varredura , Minerais , Pele
12.
Sci Rep ; 10(1): 14124, 2020 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-32839490

RESUMO

The present study shows chronic adjustments in the myotendinous junction (MTJ) in response to different ladder-based resistance training (LRT) protocols. Thirty adult male Wistar rats were divided into groups: sedentary (S), calisthenics (LRT without additional load [C]), and resistance-trained (LRT with extra weight [R]). We demonstrated longer lengths of sarcoplasmatic invaginations in the trained groups; however, evaginations were seen mainly in group R. We showed a greater thickness of sarcoplasmatic invaginations in groups C and R, in addition to greater evaginations in R. We also observed thinner basal lamina in trained groups. The support collagen layer (SCL) adjacent to the MTJ and the diameters of the transverse fibrils were larger in R. We also discovered a niche of telocytes in the MTJ with electron micrographs of the plantar muscle and with immunostaining with CD34+ in the gastrocnemius muscle near the blood vessels and pericytes. We concluded that the continuous adjustments in the MTJ ultrastructure were the result of tissue plasticity induced by LRT, which is causally related to muscle hypertrophy and, consequently, to the remodeling of the contact interface. Also, we reveal the existence of a collagen layer adjacent to MTJ and discover a new micro anatomic location of telocytes.


Assuntos
Fibras Musculares Esqueléticas/fisiologia , Músculo Esquelético/fisiologia , Condicionamento Físico Animal/fisiologia , Treinamento Resistido/métodos , Retículo Sarcoplasmático/fisiologia , Telócitos/fisiologia , Adaptação Fisiológica/fisiologia , Junções Aderentes/fisiologia , Animais , Membrana Basal/fisiologia , Adesão Celular , Movimento Celular/fisiologia , Junções Célula-Matriz/fisiologia , Colágeno/metabolismo , Masculino , Ratos , Ratos Wistar , Comportamento Sedentário
13.
Histochem Cell Biol ; 154(6): 621-628, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32797254

RESUMO

Joint immobilization is commonly used as a conservative treatment for osteoarticular and musculotendinous traumas. However, joint immobilization might elicit degenerative effects on the neuromuscular system and muscle atrophy. For this reason, the choice of strategies that mitigate these effects is essential in the post-immobilization period. Therefore, this study aimed to investigate the impact of aquatic training on the morphology of muscle fibers and motor endplates of the gastrocnemius muscle in the post-immobilization period. Male Wistar rats (90 days old) were divided into groups: Sedentary: no procedure; Immobilization: joint immobilization protocol (10 days); Immobilization/non-training: joint immobilization protocol (10 days) followed by four weeks without exercise intervention; Immobilization/training: joint immobilization protocol (10 days) and post-immobilization aquatic training (4 weeks). After the procedures, we quantified the cross-sectional area (CSA), volume and numerical density of different myofibers types, and total and stained area and perimeter of the motor endplate. We demonstrate the following main results: (a) short-term joint immobilization resulted in myofibers atrophy; however, we verified a small change in the postsynaptic component; (b) the period of inactivity after immobilization caused severe changes in the motor endplate (lower stained area, stained perimeter, total area, and total perimeter) and maintenance of muscle atrophy due to immobilization; (c) the prescription of post-immobilization exercise proved to be effective in restoring muscle morphology and inducing plasticity in the motor endplate. We conclude that short-term joint immobilization (10 days) results in atrophy type I and II myofibers, in addition to a decline in the total perimeter of the motor endplate. Besides, the post-immobilization period appears to be decisive in muscle and postsynaptic remodeling. Thus, aquatic training is effective in stimulating adjustments associated with muscle hypertrophy and plasticity of the motor endplate during the post-immobilization period.


Assuntos
Terapia por Exercício , Placa Motora/metabolismo , Músculo Esquelético/metabolismo , Junção Neuromuscular/metabolismo , Animais , Masculino , Ratos , Ratos Wistar
14.
Microsc Res Tech ; 83(10): 1190-1197, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32500573

RESUMO

The myofibrillary types establish to the skeletal muscle functional and adaptive properties that influence the sarcomeric arrangement during muscle contraction and may have repercussions on an important related force transmission region of the locomotor apparatus, the myotendinous junction (MTJ). This study aimed to describe changes in myofibrillary type and sarcomeric lengths in the belly muscle and MTJ of the soleus and plantaris muscles associated with training protocols in vertical ladder. Thirty adults male Wistar rats were divided into three groups (n = 10): Control (CTR), No-load Training (NLT), and Load Training (LT). Morphoquantitative analysis of different fibers types and sarcomere lengths were performed in distinct regions of plantaris and soleus muscles. In the plantaris muscle with both trainings, there was an increase in the cross-sectional area (CSA) in Type I and II fibers (p < .0001) while sarcomeric lengths revealed greater lengths in the proximal and distal sarcomeres of NLT, although in the LT we found greater lengths in the belly and MTJ sarcomeres. The soleus muscle showed an increase in CSA muscle fiber only in the NLT (p < .0001) and revealed alterations in belly and MTJ sarcomere lengths with training. We concluded that plantaris muscle has an adaptive effect directly associated with training load, with hypertrophy in both trainings and sarcomere length inverse from belly and MTJ, in LT associated with increased force generation and transmission at the MTJ, although soleus muscle has a lower adaptive response to training stimuli with variation in the belly and distal sarcomere of the MTJ.


Assuntos
Sarcômeros , Tendões , Animais , Masculino , Fibras Musculares Esqueléticas , Músculo Esquelético , Ratos , Ratos Wistar
15.
Anat Histol Embryol ; 49(4): 532-540, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32237176

RESUMO

The tongue is an important organ in species due to its feeding functions, and its structure is influenced by the habitat and diet. The Collared Peccary (Pecari tajacu, Linnaeus, 1758) is a terrestrial mammal that is distributed on the American continents and has an omnivorous diet. This study aimed to describe the morphological characteristics of the tongue, lingual papillae and the connective tissue cores (CTCs) of the Collared Peccary. Eight tongues were collected from the Wild Animals Multiplication Center. The samples (n = 6) were processed for three-dimensional analysis of their dorsal epithelium, and their CTCs by scanning electron microscopy and the other samples (n = 2) were used to observe ultrastructural characteristics by transmission electron microscopy. Filiform papillae were observed in the lingual apex and body with their conical CTC demonstrating ripples in their extent. Two types of fungiform papillae were observed, the first in the apex and body with a dome-shaped CTC and the second forming a dorsolateral line with a radial pattern CTC. The vallate papillae were bilateral in the caudal region with the CTCs, characterised by numerous projections, and foliate papilla were not observed. We found a new type of papilla anteriorly to the vallate papilla with an irregular groove and a CTC formed by triangular-shaped projections with a duct opening at the top. We concluded that the lingual papillae of the Collared Peccary resemble those papillae of other mammals, however, were revealed another form of their CTCs and a new lingual papillae morphological description.


Assuntos
Artiodáctilos/anatomia & histologia , Língua/anatomia & histologia , Animais , Tecido Conjuntivo/anatomia & histologia , Tecido Conjuntivo/ultraestrutura , Imageamento Tridimensional/veterinária , Microscopia Eletrônica de Varredura/veterinária , Microscopia Eletrônica de Transmissão/veterinária , Língua/ultraestrutura
16.
Microsc Res Tech ; 81(8): 816-822, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29689628

RESUMO

The study aims to describe the tissue plasticity of MTJ through the morphological analysis of MTJ soleus in ovariectomized aged female Wistar rats submitted to aquatic training. Forty aged Wistar rats, 1 year and 2 months of age, were divided into four groups: sedentary (S), trained (T), ovariectomized (O), and trained/ovariectomized (OT). Employing the transmission electron microscopy, the ultrastructural and morphometric elements were revealed. In the S group, changes in morphological characteristics as a consequence of the aging process were seen, demonstrated by the conical shape of the muscle cell extremity, a large area with collagen deposit, and misalignment of sarcomeres in series. The T group presented ample adjustments when revealed the organization of MTJ, through the increase of the contact area and greater lengths of sarcoplasmatic invaginations and evaginations. The O group revealed extensive tissue disorganization with muscle atrophy, reduction of MTJ contact area, and consequently, changes in sarcoplasmatic invaginations and evaginations. The OT group demonstrated extensive remodeling with restructuring MTJ through the increase of tissue contact area, extensive organization, parallel arrangement, and increased length of sarcoplasmatic invaginations and evaginations. The distal sarcomeres presented higher lengths compared to the proximal sarcomeres in both the groups. We conclude that aquatic training was effective in the organization and structural remodeling of the myotendinous interface of ovariectomized aged rats. There was a greater area of contact, and consequently, greater resistance in the myotendinous interface promoting a lower predisposition to injuries.


Assuntos
Adaptação Fisiológica , Músculo Esquelético/fisiologia , Músculo Esquelético/ultraestrutura , Ovariectomia , Condicionamento Físico Animal , Tendões/fisiologia , Tendões/ultraestrutura , Animais , Feminino , Microscopia Eletrônica de Transmissão , Células Musculares/ultraestrutura , Ratos Wistar
17.
Lasers Med Sci ; 32(4): 833-840, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28314941

RESUMO

Inferior alveolar nerve (IAN) injuries may occur during various dental routine procedures, especially in the removal of impacted lower third molars, and nerve recovery in these cases is a great challenge in dentistry. Here, the IAN crush injury model was used to assess the efficacy of photobiomodulation (PBM) in the recovery of the IAN in rats following crushing injury (a partial lesion). Rats were divided into four experimental groups: without any procedure, IAN crush injury, and IAN crush injury with PBM and sham group with PBM. Treatment was started 2 days after surgery, above the site of injury, and was performed every other day, totaling 10 sessions. Rats were irradiated with GaAs Laser (Gallium Arsenide, Laserpulse, Ibramed Brazil) emitting a wavelength of 904 nm, an output power of 70 mWpk, beam spot size at target ∼0.1 cm2, a frequency of 9500 Hz, a pulse time 60 ns, and an energy density of 6 J/cm2. Nerve recovery was investigated by measuring the morphometric data of the IAN using TEM and by the expression of laminin, neurofilaments (NFs), and myelin protein zero (MPZ) using Western blot analysis. We found that IAN-injured rats which received PBM had a significant improvement of IAN morphometry when compared to IAN-injured rats without PBM. In parallel, all MPZ, laminin, and NFs exhibited a decrease after PBM. The results of this study indicate that the correlation between the peripheral nerve ultrastructure and the associated protein expression shows the beneficial effects of PBM.


Assuntos
Terapia com Luz de Baixa Intensidade , Nervo Mandibular/metabolismo , Nervo Mandibular/patologia , Compressão Nervosa , Neuropeptídeos/metabolismo , Animais , Densitometria , Filamentos Intermediários/metabolismo , Laminina/metabolismo , Masculino , Nervo Mandibular/ultraestrutura , Proteína P0 da Mielina/metabolismo , Ratos Wistar
18.
Lasers Med Sci ; 32(3): 495-501, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28138810

RESUMO

For better evaluation of the efficacy of low-level laser therapy in treating painful diabetic neuropathy and in protecting nerve fiber damage, we conducted a study with type 1 diabetic rats induced by streptozotocin. It is well known that diabetic peripheral neuropathy is the leading cause of pain in those individuals who suffer from diabetes. Despite the efficacy of insulin in controlling glucose level in blood, there is no effective treatment to prevent or reverse neuropathic damage for total pain relief.Male Wistar rats were divided into saline, vehicle, and treatment groups. A single intraperitoneal (i.p.) injection of streptozotocin (STZ) (85 mg/kg) was administered for the induction of diabetes. The von Frey filaments were used to assess nociceptive thresholds (allodynia). Behavioral measurements were accessed 14, 28, 48, and 56 days after STZ administration. Rats were irradiated with GaAs Laser (Gallium Arsenide, Laserpulse, Ibramed Brazil) emitting a wavelength of 904 nm, an output power of 45 mWpk, beam spot size at target 0.13 cm2, a frequency of 9500 Hz, a pulse time 60 ns, and an energy density of 6,23 J/cm2.The application of four sessions of low-level laser therapy was sufficient to reverse allodynia and protect peripheral nerve damage in diabetic rats.The results of this study indicate that low-level laser therapy is feasible to treat painful diabetic condition in rats using this protocol. Although its efficacy in reversing painful stimuli and protecting nerve fibers from damage was demonstrated, this treatment protocol must be further evaluated in biochemical levels to confirm its biological effects.


Assuntos
Diabetes Mellitus Tipo 1/complicações , Neuropatias Diabéticas/radioterapia , Hiperalgesia/radioterapia , Lasers Semicondutores/uso terapêutico , Terapia com Luz de Baixa Intensidade/métodos , Animais , Diabetes Mellitus Experimental/fisiopatologia , Lasers Semicondutores/efeitos adversos , Terapia com Luz de Baixa Intensidade/efeitos adversos , Masculino , Dor/complicações , Ratos , Ratos Wistar , Estreptozocina
19.
BMC Res Notes ; 8: 713, 2015 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-26601719

RESUMO

BACKGROUND: During almost one-third of our life, maturation of the nervous system promotes strength and muscle mass increase. However, as age advances, the nervous system begins to suffer a slow and continue reduction of its functions. Neuromuscular junction (NMJ) is one of the structures of which change due to aging process. Physical training leads to significant adjustments in NMJs of young and aged animals. Nevertheless, studies that aimed to investigate this effect have, in many cases, methodological variables that may have some influence on the result. Thus, this study aimed to carry out a systematic review about the effects of exercise training on the NMJ compartments of young, adult and aged animals. RESULTS: We searched PubMed, Google Scholar, Science Direct, Scielo and Lilacs databases for animal experimental studies that studied exercise effects on the NMJs components across age. After inclusion and exclusion criteria, we included nine articles in systematic review and two for meta-analysis (young/adult NMJ). CONCLUSIONS: We identified that exercise training cause NMJ hypertrophy on young animals and NMJ compression on aged ones. However, many methodological issues such as age, skeletal muscle and fibers type, and type of exercise and training protocol might influence the results. Graphical abstract: Flow gram is actually to be show at results section as Fig 1.


Assuntos
Junção Neuromuscular/fisiologia , Condicionamento Físico Animal , Animais , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Ratos , Ratos Endogâmicos F344 , Ratos Sprague-Dawley , Ratos Wistar
20.
Growth Factors ; 33(1): 8-13, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25489629

RESUMO

Neurotrophins are crucial in relation to axonal regrowth and remyelination following injury; and neural mobilization (NM) is a noninvasive therapy that clinically is effective in neuropathic pain treatment, but its mechanisms remains unclear. We examined the effects of NM on the regeneration of sciatic nerve after chronic constriction injury (CCI) in rats. The CCI was performed on adult male rats, submitted to 10 sessions of NM, starting 14 days after CCI. Then, the nerves were analyzed using transmission electron microscopy and western blot for neural growth factor (NGF) and myelin protein zero (MPZ). We observed an increase of NGF and MPZ after CCI and NM. Electron microscopy revealed that CCI-NM samples had high numbers of axons possessing myelin sheaths of normal thickness and less inter-axonal fibrosis than the CCI. These data suggest that NM is effective in facilitating nerve regeneration and NGF and MPZ are involved in this effect.


Assuntos
Manipulações Musculoesqueléticas , Proteína P0 da Mielina/metabolismo , Fator de Crescimento Neural/metabolismo , Regeneração Nervosa , Traumatismos dos Nervos Periféricos/metabolismo , Animais , Axônios/metabolismo , Axônios/ultraestrutura , Masculino , Proteína P0 da Mielina/genética , Fator de Crescimento Neural/genética , Traumatismos dos Nervos Periféricos/terapia , Ratos , Ratos Wistar , Nervo Isquiático/lesões , Nervo Isquiático/metabolismo , Nervo Isquiático/fisiologia
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