Skeletal Muscular Tissue Research Articles

Dl-3-n-Butylphthalide (NBP) Mitigates Muscular Injury Induced by Limb Ischemia/Reperfusion in Mice through the HMGB1/TLR4/NF-κB Pathway.

Objective Limb ischemia/reperfusion (I/R) injury is a clinical syndrome associated with severe damages to skeletal muscles and other fatal outcomes. Oxidative stress and inflammatory response play vital roles in the development of limb I/R injury. Existing evidence further indicates that Dl-3-n-butylphthalide (NBP) has anti-inflammatory and antioxidative properties. However, whether NBP can protect skeletal muscles from limb I/R injury and the mechanism in mediating the action of NBP treatment still remain to be investigated, which are the focuses of the current study. Methods The model of limb I/R injury was established and H&E staining was adopted to assess the pathological changes in skeletal muscles following limb I/R injury. Additionally, the W/D ratio of muscle tissue was also measured. ELISA and biochemical tests were carried out to measure the levels of inflammatory cytokines and oxidative stress in mouse models of limb I/R injury. Moreover, the levels of the HMGB1/TLR4/NF-κB pathway-related proteins were also determined using immunohistochemistry and immunoblotting. Results It was established that NBP treatment alleviated I/R-induced pathological changes in muscular tissue of mice, accompanied by lower W/D ratio of skeletal muscular tissue. Meanwhile, the limb I/R-induced inflammation and oxidative stress in skeletal muscles of mice were also inhibited by NBP. Mechanistic study indicated that the alleviatory effect of NBP was ascribed to inactivation of the HMGB1/TLR4/NF-κB pathway. Conclusions Our findings highlighted the potential of NBP as a novel strategy for limb I/R-driven muscle tissue damages by suppressing inflammatory response and oxidative stress via the HMGB1/TLR4/NF-κB pathway.

Infrared laser exposure in combination with branchedchain amino acid stimulates physiological adaptation of skeletal muscles

Laser exposure stimulates cell proliferation and tissue repair. Branched-chain amino acids (BCAA) are widely used in sports medicine as a stimulator of anabolic processes. However, there is no evidence of the effect of combined laser and BCAA application on skeletal muscle morphometric characteristics during exercise in the training process.Purpose: to study the effect of infrared laser exposure in combination with amino acid at myosatellitocytes and skeletal muscle myocytes during swimming training.Material and methods. The experiment was conducted on 30 Wistar rats: Group 1 – intact, Group 2 – dynamic control (trainings with endurance swimming), Group 3 – trainings and BCAA, Group 4 – trainings and laser exposure at hip muscles (970 nm, 1 W, 60 s), Group 5 – combined exposure to laser and BCAA. Trainings were three times a week for 6 weeks; laser session was after each training. Samples of the bipedal thigh muscle were fixed with formalin; histological sections were stained with hematoxylin-eosin. The morphometric analysis of the digital image of objects with statistical processing by Mann – Whitney method was made.Results. Laser exposure combined with BCAA during trainings increased the nuclei area and the number of myosatellites and myocytes; it also enlarged the cross section of muscle fibers which was more pronounced if to compare with isolated laser irradiation of the muscle or BCAA.Conclusions. Infrared laser exposure in combination with branched-chain amino acids effectively stimulates regeneration due to hyperplasia and hypertrophy of skeletal muscular tissue, thus providing physiological adaptation in the training process.

In Vitro, In Vivo, and In Silico Studies of Cumanin Diacetate as a Potential Drug against Trypanosoma cruzi Infection.

The sesquiterpene lactones cumanin, helenalin, and hymenin and their semisynthetic derivatives were evaluated against Trypanosoma cruzi epimastigotes. The cytotoxicity of the compounds was evaluated on murine splenocytes. Cumanin diacetate was one of the most active and selective compounds [IC50 = 3.20 ± 0.52 μg/mL, selectivity index (SI) = 26.0]. This sesquiterpene lactone was selected for its evaluation on trypomastigote and amastigote forms of the parasite. The diacetylated derivative of cumanin showed moderate activity on trypomastigotes (IC50 = 32.4 ± 5.8 μg/mL). However, this compound was able to efficiently inhibit parasite replication with an IC50 value of 2.2 ± 0.05 μg/mL against the amastigote forms. Cumanin diacetate showed selectivity against the intracellular forms of Trypanosoma cruzi with an SI value of 52.7. This cumanin analogue was also active on an in vivo model of Chagas disease, leading to a reduction in the parasitemia levels in comparison with nontreated animals. Histopathological analysis of skeletal muscular tissues from treated mice showed only focal interstitial lymphocyte inflammatory infiltrates with slight myocyte necrosis; in contrast, nontreated animals showed severe lymphocyte inflammatory infiltrates with necrosis of the myocytes. A molecular docking study of cumanin and its derivatives on trypanothione reductase from T. cruzi (TcTR) was performed. The results of ΔG docking achieved let the identification of diacetylated and O-alkylated derivatives of cumanin as good inhibitors of TcTR. Cumanin diacetate could be considered a potential candidate for further studies for the development of new therapies against Chagas disease.

Асоційовані зміни гормонального статусу та скелетної м’язової тканини у жінок старших вікових груп

У статті наведені причини розвитку саркопенії у людей старших вікових груп — синдрому, що характеризується прогресивним і генералізованим зниженням скелетної м’язової маси, сили та її функції. Висвітлено дані літератури щодо впливу соматотропного гормона на скелетну м’язову тканину, а також результати дослідження, проведеного на базі ДУ «Інститут геронтології імені Д.Ф. Чеботарьова НАМН України». Метою дослідження було вивчити зв’язок між показниками скелетної мускулатури та рівнем соматотропного гормона, загального та вільного тестостерону. Стан знежиреної маси всього тіла, верхніх та нижніх кінцівок оцінювали за допомогою двофотонної рентгенівської абсорбціометрії (Prodigy, GEHC Lunar, Madison, WI, США). Силу скелетної мускулатури оцінювали за допомогою кистьового пружинного динамометра, що пацієнт стискає кистю витягнутої верхньої кінцівки. Для визначення функціональних можливостей скелетних м’язів оцінювали швидкість ходьби обстежених жінок за чотириметровим тестом. Визначення рівня загального та вільного тестостерону та соматотропного гормона в сироватці крові обстежених жінок проведено за допомогою імунохемілюмінесцентного методу з використанням обладнання Immulite 2000 виробництва компанії Siemens DPC (США). Під час дослідження встановлено зв’язок рівня соматотропного гормона та апендикулярної знежиреної маси; рівня загального, вільного тестостерону, соматотропного гормона та сили скелетної мускулатури; рівня загального, вільного тестостерону та функціональних можливостей скелетної м’язової тканини.

Miniaturized Electrochemical Sensors to Monitor Fetal Hypoxia and Acidosis in a Pregnant Sheep Model.

Perinatal asphyxia is a major cause of severe brain damage and death. For its prenatal identification, Doppler ultrasound has been used as a surrogate marker of fetal hypoxia. However, Doppler evaluation cannot be performed continuously. We have evaluated the performance of a miniaturized multiparametric sensor aiming to evaluate tissular oxygen and pH changes continuously in an umbilical cord occlusion (UCO) sheep model. The electrochemical sensors were inserted in fetal hindlimb skeletal muscle and electrochemical signals were recorded. Fetal hemodynamic changes and metabolic status were also monitored during the experiment. Additionally, histological assessment of the tissue surrounding the sensors was performed. Both electrochemical sensors detected the pO2 and pH changes induced by the UCO and these changes were correlated with hemodynamic parameters as well as with pH and oxygen content in the blood. Finally, histological assessment revealed no signs of alteration on the same day of insertion. This study provides the first evidence showing the application of miniaturized multiparametric electrochemical sensors detecting changes in oxygen and pH in skeletal muscular tissue in a fetal sheep model.

Trypanocidal Activity of Four Sesquiterpene Lactones Isolated from Asteraceae Species.

The sesquiterpene lactones eupatoriopicrin, estafietin, eupahakonenin B and minimolide have been isolated from Argentinean Astearaceae species and have been found to be active against Trypanosoma cruzi epimastigotes. The aim of this work was to evaluate the activity of these compounds by analyzing their effect against the stages of the parasites that are infective for the human. Even more interesting, we aimed to determine the effect of the most active and selective compound on an in vivo model of T. cruzi infection. Eupatoriopicrin was the most active against amastigotes and tripomastigotes (IC50 = 2.3 µg/mL, and 7.2 µg/mL, respectively) and displayed a high selectivity index. This compound was selected to study on an in vivo model of T. cruzi infection. The administration of 1 mg/kg/day of eupatoriopicrin for five consecutive days to infected mice produced a significant reduction in the parasitaemia levels in comparison with non-treated animals (area under parasitaemia curves 4.48 vs. 30.47, respectively). Skeletal muscular tissues from eupatopicrin-treated mice displayed only focal and interstitial lymphocyte inflammatory infiltrates and small areas of necrotic; by contrast, skeletal tissues from T. cruzi infected mice treated with the vehicle showed severe lymphocyte inflammatory infiltrates with necrosis of the adjacent myocytes. The results indicate that eupatoriopicrin could be considered a promising candidate for the development of new therapeutic agents for Chagas disease.

Kudoa ajurutellus n. sp. (Multivalvulida: Kudoidae), a parasite of the skeletal musculature of the Bressou sea catfish, Aspistor quadriscutis, in northeastern of the State of Pará.

Kudoa ajurutellus n. sp. (Multivalvulida: Kudoidae) is described as a parasite of the Bressou catfish, Aspistor quadriscutis (Siluriformes) collected at Ajuruteua beach, northeastern Pará, Brazil. The new species is described based on the morphology of the spores and the sequence of the 18S rDNA. This parasite was found only in the skeletal muscular tissue of fish hosts. In the apical view, the spores were pseudo-quadrangular in shape, with rounded borders, and four symmetrical capsules. The spores are 6.63±0.53 μm in length and 8.16±0.75 μm in width. The polar capsules are piriform, 3.45±0.30 μm in length and 1.87±0.15 μm in width. The phylogenetic analysis based on the sequence of the 18S rDNA gene indicated that the new species is clearly distinct from all other Kudoa species, and that the degree of differentiation is constant with the existence of a new species of the genus Kudoa. This is the first marine Kudoa species recorded in northeastern of the State of Pará.

Morphological Description of Levator Ani Muscle in Rats

The aim of the research: the study of structural morphologic features of levator ani muscle in white laboratory rats. Materials and methods. Five male and five female laboratory rats 300–420 g of weight were observed as an object of investigation. The experimental animals were kept in standard conditions in vivarium with the free access to water and food. The methods of preparation, histochemistry, optical and electronic microscopy were used during the investigation. Results . It was stated that in male rats, levator ani muscle is represented by a single complex without a clear differentiation into compartments. In females, the iliocaudal and pubocaudal portions of levator ani muscle are clearly differentiated. The iliocaudal muscle is initially attached to the internal part of iliac bone, pubocaudal muscle is initially attached to the posterior part of pubic bone below pubic symphysis. The other ends of the muscles are attached through their tendons to the anterior surface of caudal vertebrae bodies Ca III –Ca VI . Meanwhile, iliocaudal muscle is attached more proximally to Ca III –Ca VI , and pubocaudal muscle is attached more distally to Ca V –Ca VI . The transverse sections of levator ani muscle in males and its pubocaudal portion in females are represented by polygonal muscle fibers, and the iliocaudal portion of levator ani muscle in females is represented by orbicular muscle fibers. Ultrastructural manifestations of sexual dimorphism among muscle fibers are not observed, they have got typical structure representative for transversal striated skeletal muscular tissue. On histochemical investigation the presence of I and II type of muscle fibers was determined, but glycolytic fibers (of the II type) prevailed. Conclusion . The obtained data indicate the presence of sexual dimorphism in levator ani muscle structure in white laboratory rats. This muscle is supposed to contribute more to provide tail movements than to strengthen small pelvis wall and protect organs.

Liquid Crystalline Networks toward Regenerative Medicine and Tissue Repair.

The communication reports the use of liquid crystalline networks (LCNs) for engineering tissue cultures with human cells. Their ability as cell scaffolds for different cell lines is demonstrated. Preliminary assessments of the material biocompatibility are performed on human dermal fibroblasts and murine muscle cells (C2C12), demonstrating that coatings or other treatments are not needed to use the acrylate-based materials as support. Moreover, it is found that adherent C2C12 cells undergo differentiation, forming multinucleated myotubes, which show the typical elongated shape, and contain bundles of stress fibers. Once biocompatibility is demonstrated, the same LCN films are used as a substrate for culturing human induced pluripotent stem cell-derived cardiomyocites (hiPSC-CMs) proving that LCNs are capable to develop adult-like dimensions and a more mature cell function in a short period of culture in respect to standard supports. The demonstrated biocompatibility together with the extraordinary features of LCNs opens to preparation of complex cell scaffolds, both patterned and stimulated, for dynamic cell culturing. The ability of these materials to improve cell maturation and differentiation will be developed toward engineered heart and skeletal muscular tissues exploring regenerative medicine toward bioartificial muscles for injured sites replacement.

Molecular characterization of four actin cDNAs and effects of 20-hydroxyecdysone on their expression in swimming crab, Portunus trituberculatus (Miers, 1876)

Crustacean muscle fibers exhibit a high level of plasticity in various growth and developmental stages and understanding its mechanism is one of the important factors to improve the commercial value of the decapod products including shrimp, lobsters, and crabs. In the present study, four cDNAs encoding actins (PotActinSK1, PotActinSK2, PotActinHT, and PotActinCT) were identified from the swimming crab (Portunus trituberculatus) using a PCR-based cloning strategy. Although the four cDNA encoding actins exhibit similarities in size and deduced amino acid sequences, their tissue expression profiles differ significantly from one another. Phylogenetic analysis revealed that muscular and cytoplasmic actins have been diverged before vertebrates were evolved and cardiac and skeletal muscular actins were branched out after the vertebrates were evolved. Based on the phylogenetic analysis and expression patterns, PotActinSK1 and SK2 belong to the slow-type skeletal muscle actins and the fast-type skeletal muscle actin has not been identified. PotActinHT showed the highest sequence similarity to Ha-ActinHT from H. americanus and appeared to be an ortholog of heart muscle actins in decapod crustaceans. PotActinCT exhibited the highest sequence similarity to the cytoplasmic actin of L. vannamei ActinT1. End-point RT-PCR results showed that PotActinSK1 and PotActinSK2 were strongly expressed in skeletal muscular tissues including chela propodus muscle, chela merus muscle, leg muscle, thoracic muscle, and there was no significant difference in the expression ratio between the two genes of those four tissues. PotActinCT was ubiquitously expressed in all the tissues, whereas PotActinHT was exclusively expressed in the heart. Interestingly, a considerable level of PotActinCT was expressed in the heart, which is similar to those of PotActinHT. The transcriptional response to 20-hydroxyecdysone (20E) injection was different in each PotActin suggesting that effects of muscle plasticity by 20E may differ in each tissue of decapod crustaceans.

鼻翼外側に生じたタングステン合金異物肉芽腫例

We report a case of foreign body granuloma caused by heavy-metal tungsten alloy outside of the nostril. A 72-year-old woman seen for subcutaneous nostril swelling had the granuloma completely resected. Histopathologically, the granuloma was caused by heavy-metal tungsten alloy that coagulatively necrosed fibrous skeletal muscular and fibrovascular tissue. The rim of the granuloma consisted of spindle cells and epithelioid cells surrounded by small lymphocytes. No foreign-body reaction was seen. The woman had no memory of when and why the foreign substance was injected or implanted. To date, ten cases of foreign body granuloma involving heavy-metal tungsten alloy, including this case, have been reported in Japan. Clinical manifestations, histopathological findings, and treatment of this lesion are discussed.

Vitamin-enriched drinks and dessert for myotoniс dystrophy patients with oropharyngeal dysfagia

Myotonic dystrophy is a multisystemic disease which mutation may influence your development and function of different organs and tissue: smooth and skeletal-muscular tissue; heart; organs of the eye, brain. This review gives a simple information about balanced diet of patients myotonic dystrophy with oropharyngeal dysphagia.

Targeted delivery of methotrexate to skeletal muscular tissue by thermosensitive magnetoliposomes

Thermosensitive magnetoliposomes (TMs) encapsulated with methotrexate (MTX) were prepared with 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) and cholesterol by reverse-phase evaporation. Encapsulation efficiency of MTX and hydrophilic magnetite Fe 2O 3-glu, liposome particle size, ζ-potential, and in vitro and in vivo drug release were studied. More than 80% of loaded MTX was released from TMs within 30 min when the environmental temperature increased from 37 °C to 41 °C, while 60% of the drug was remained inside TMs for up to 24 h at 37 °C. Furthermore, the pharmacokinetics and tissue distribution study showed that TMs significantly increased the accumulation of MTX in the skeletal muscular tissue when exposed to an external constant magnetic field and heated to 41 °C compared to the absence of the magnetic field and heating. Therefore, the results in this study suggested that TMs prepared by reverse-phase evaporation can archive a good magnetic targeting effect and fast drug release in response to hyperthermia, which implies their great potential of application in cancer therapy.

Muscle spindles in elongation of the extremity: Proprioceptive conflict or activity deficit?

Comparison of electrophysiological and morphological parameters of shin muscles of experimental animals during shin elongation by Ilizarov's method indicates involvement of muscle spindles into reconstruction of the skeletal muscular tissue in response to its dosed distraction, which results in temporary deficit of specific somatosensory afferentation.

Histochemical analysis of skeletal muscular tissues of pigs according to genotype MYF4

The results of histochemical analysis of three muscles m. triceps brachii (MTB), m. longissimus thoracicus (MLT) and m. rectus femoris (MRF) of two groups of pigs created according to the genotypes MYF 4 are presented. Determination of MYF 4 genotypes was made by PCR method and for histochemical analysis was used 5 animals detected as homozygote MYF 4- AA type and 5 animals of heterozygote genotype myogenin-AB out of the total of 25 individual animals tested. The histochemical analysis proved that homozygotes AA have had bigger fat cells than heterozygotes AB in three studied muscles in average. The size of fat cells in MLT - 41.10?m or 38.50 ?m respectively dominated in both groups of animals. Percentage surface representation of interstitial tissues was higher in the studied muscles of heterozygote MYF 4-AB. The volume of ligaments was the highest in MRF (3.80% or 3.90% respectively) in both groups (myogenin - AA and AB). The average thickness was of three studied muscles muscle fibres higher at homozygote genotype myogenin-AA than in heterozygote myogenin-AB. The thickest fibres in both genotypes were in MRF (88.60 ?m, and 84.72 ?m respectively) and the lowest in MTB (73.30 and 69.40 ?m respectively). The highest values of muscle fibres thickness were detected in ?-White fibres. Their percentage surface representation corresponded to this in all three types of muscles of both studied genotype myogenin groups.

Hepatic “split lesion” in a fatal electrocution case

The first recorded death caused by electrical current from an external source was reported in 1879, when a carpenter in Lyon, France, inadvertently contacted a 250 V alternating current generator [1]. Electrical injuries (excluding lightning) are responsible for >500 deaths per year in the USA. A little more than half of them occur in the workplace and constitute the fourth leading cause of work-related traumatic death (5–6% of all worker’s deaths) [2]. Medical literature typically categorizes electrocution according to the level of applied voltage: low voltage (less than 1000 V) and high voltage (greater than 1000 V); as reported from medical-legal practice, 14–40% of mortal electrocution are caused by high-voltage injuries [3,4]. It is well known that an electrical shock may cause death or any degree of damage to various organs and systems; the severity of electric shock injury is dependent upon many variables: type of current, level of applied voltage, duration of shock, body contact surface area, resistance of tissue involved, contact with water or metal conductor and current pathway through the body [5]. The electrical shock may strike the victim’s central nervous system, the cardiovascular apparatus, the skeletal muscular tissue, the lungs, the skin and other internal organs [6]. Severe abdominal visceral injuries by electricity are a rare entity; in particular, we rarely come across cases of hepatic lesions. In

Effects of Huanglian Jiedu Decoction on phosphatidylinositol-3-kinase expression in target tissues of type 2 diabetic rats

To observe the effects of Huanglian Jiedu Decoction (HLJDD), a traditional Chinese compound herbal medicine, on p85 mRNA and protein expressions of phosphatidylinositol-3-kinase (PI-3K) in target tissues (skeletal muscular and adipose tissues) in rats with type 2 diabetes mellitus (T2DM) and to investigate the molecular mechanism of HLJDD in treating T2DM. The male Wistar rats were injected with streptozotocin (STZ) 30 mg/kg through tail vein, and fed with high-fat and high-caloric diets to induce T2DM. Then the rats were randomly divided into untreated group, aspirin-treated group and HLJDD group, and treated correspondingly. Meanwhile, a group of normal animals without any treatment was set up for normal control group. Ten weeks later, serum fasting blood glucose (FBG), serum fasting insulin (FINS) and oral glucose tolerance test (OGTT) were routinely determined. The expressions of PI-3K p85 mRNA and protein in skeletal muscle and adipose tissue were determined with RT-PCR and Western blotting before and after insulin treatment. Compared with the untreated group, the FBG and OGTT levels in T2DM rats treated with HLJDD decreased significantly (P<0.05). The FINS in HLJDD group was lower than that in the normal control group (P<0.05), but was not significantly different from that in the untreated group. The PI-3K p85 mRNA and protein expressions in HLJDD group obviously increased, as compared with those in the untreated group. The effect of HLJDD in treating T2DM was probably associated with its improvement of PI-3K p85 mRNA and protein expressions in skeletal muscle and adipose tissue of the T2DM rats.

The effect of endurance training on the neovascularization of skeletal musculature

To quantify the capillaries in the skeletal muscular tissue of mice with induced peripheral arterial insufficiency, after endurance training. It was used Wistar mice in 70 days age range, subjected to the total occlusion of right femoral artery. The animals were divided into two groups: sedentary group (SG; n = 05), subjected to activities in the cage; and trained group (TG; n = 05), subjected to an endurance training in cycle ergometer twice a day 17m/min, by 5 minutes, 5 days per week during 10 weeks. The analysis was realized by the histologic observation of the vastus medialis muscle of injured member. The average number of capillaries in the muscular tissue was greater in TG (5,2 +/- 0,83) than in SG (1,6 +/- 1,14) (p < 0,05). In animals with induction of peripheral arterial insufficiency, the endurance training provides a process of muscular adaptation which is observed by the increase in the number of capillaries of animals subjected to this kind of training.

Usefulness of Immunological Detection of the Human Telomerase Reverse Transcriptase

Objective: Recent years have seen a considerable wealth of studies conducted on the potential usefulness of telomerase determination in diagnosis, prognosis and targeted cancer therapy. The frequently used Telomeric Repeat Amplification Protocol assay suffers from some drawbacks, the most important being the rate of false positives. In situ analysis using well characterised antibodies directed against the human telomerase reverse transcriptase (hTERT) would therefore appear to be important to morphologically identify the nature of telomerase positive cells. Methods: We performed immunostaining in a series of cultured cells and in normal, preneoplastic and tumour tissues from different organs using a monoclonal antibody directed against the catalytic subunit of telomerase. Results: Immunoreactivity was not observed in perennial cells of terminally differentiated cardiac and skeletal muscular tissues or in small pyramidal cells of the cerebral cortex. Conversely, it was found in other normal somatic tissues as well as in precancerous lesions and in all tumour histotypes. Conclusions: Immunohistochemistry with a well characterised hTERT-specific monoclonal antibody permitted the identification of hTERT immunopositive cells in normal somatic tissues. Whether hTERT protein detected by immunostaining with hTERT-specific Tel 3 36-10 antibody is actually the degraded form of the protein that retains hTERT antigenicity but not enzymatic function, or whether it represents the real, potentially functional catalytic subunit of the enzyme, immunohistochemistry would not seem to represent a useful tool to investigate the role of telomerase and the mechanisms involved in its regulation.

Histochemical study of the skeletal muscle in children with chronic renal failure in dialysis treatment.

Among the modifications occurring in the uremic organism, in addition to the consequences of dialysis, myopathy and peripheral neuropathy are very significant. Children are particularly affected, as their growth and development are jeopardized. Histochemistry of muscular biopsy was used to study eighteen children with end-stage renal failure under dialysis during a ten-month period. According to our results, the skeletal muscular tissue presented the following types of alterations: atrophy, type grouping, lipidosis, glycogen depletion and mitochondrial proliferation.