Chemical characterization and effects of volatile oil of Alpinia zerumbet on the quality of collagen deposition and caveolin-1 expression in a muscular fibrosis murine model

This study evaluated the effect of the volatile oil of Alpinia zerumbet (VOAz) on caveolin-1 gene expression and muscular fibrosis. The rats were immobilized to induce fibrosis of the gastrocnemius muscle, and they were treated with VOAz. Collagen quality was assessed by histology and the expression of the caveolin-1 (CAV-1) gene was evaluated using qPCR. Histomorphological analysis indicated a significant reduction in the perimeter, width, and intensity of collagen in the treated groups, thus showing that the oil was effective in regulating the quality of collagen at the three concentrations. The results of expression levels suggested a decrease in the lesioned group and in two treatment groups (0.0115 µg/g and 0.009 µg/g). However, with the lowest concentration (0.0065 µg/g), no significant difference was observed, with levels similar to those found in healthy tissue. Therefore, the results showed that VOAz has the potential to be a non-invasive and low-cost alternative to aid in the treatment of muscular fibrosis.

HIF-1α Negatively Regulates Irisin Expression Which Involves in Muscle Atrophy Induced by Hypoxia

Exposure to high altitude environment leads to skeletal muscle atrophy. As a hormone secreted by skeletal muscles after exercise, irisin contributes to promoting muscle regeneration and ameliorating skeletal muscle atrophy, but its role in hypoxia-induced skeletal muscle atrophy is still unclear. Our results showed that 4 w of hypoxia exposure significantly reduced body weight and gastrocnemius muscle mass of mice, as well as grip strength and the duration time of treadmill exercise. Hypoxic treatment increased HIF-1α expression and decreased both the circulation level of irisin and its precursor protein FNDC5 expression in skeletal muscle. In in vitro, CoCl2-induced chemical hypoxia and 1% O2 ambient hypoxia both reduced FNDC5, along with the increase in HIF-1α. Moreover, the decline in the area and diameter of myotubes caused by hypoxia were rescued by inhibiting HIF-1α via YC-1. Collectively, our research indicated that FNDC5/irisin was negatively regulated by HIF-1α and could participate in the regulation of muscle atrophy caused by hypoxia.

Electrospun Polycaprolactone (PCL)-Amnion Nanofibrous Membrane Promotes Nerve Repair after Neurolysis

Peripheral nerve adhesion after neurolysis leads to nerve dysfunction, limiting nerve regeneration and functional recovery. We previously developed an electrospun polycaprolactone (PCL)-amnion nanofibrous membrane for preventing adhesion formation. In this study, we investigated the effect of protective nerve wrapping and promoting nerve regeneration in a rat sciatic nerve compression model. A total of 96 SD rats after sciatic nerve chronic compression were randomly divided into three groups: the PCL-amniotic group, in which nerves were wrapped with a PCL-amniotic membrane for treatment; the chitosan group, in which nerves were wrapped with a clinically used chitosan hydrogel; the control group, which involved neurolysis alone without treatment. Twelve weeks postoperatively, the nerve regeneration was evaluated by general and ultrastructure observation, as well as the expressions of neuronal regeneration and inflammatory reaction biomarkers. The nerve functions were assessed with gastrocnemius muscle measurement, hot-plate test, and walking track analysis. Compared with the chitosan hydrogel, the PCL-amnion nanofibrous membrane significantly reduced peripheral nerve adhesion and promoted nerve regeneration. The morphological properties of axons in the nerve wrap group were preserved. Intraneural macrophage invasion, as assessed by the number of CD68-positive cells, was less severe in the PCL-amnion group than in the other groups. Additionally, the gastrocnemius muscle weight and muscle bundle area were significantly higher in the PCL-amnion group than those in the chitosan group. The abilities of sense and movement of the rats in the PCL-amnion group were significantly improved compared to the other groups. In summary, electrospun PCL-amnion nanofibrous membranes effectively prevented post-neurolysis peripheral nerves from developing adhesion, whereas promoted nerve repair and regeneration, which make PCL-amnion nanofibrous membranes a promising biomaterial for clinical application.

Intra- and extra-capsular ganglia at the gastrocnemius origin and association with meniscal tears and severity of osteoarthritis of the knee joint

Background The association between size of ganglia or type of ganglia (intra-articular or extra-articular) and meniscal tears or severity of the osteoarthritis (OA) is not evaluated. Purpose To evaluate the prevalence, size, and location of intra- and extra-capsular ganglia at the gastrocnemius origin and to assess their associations with meniscal injury and grades of OA. Material and Methods This study included 301 consecutive patients who had knee pain and had undergone magnetic resonance imaging (MRI) of the knee. We evaluated presence of ganglia at the gastrocnemius muscle origin site and diagnosed whether it was an intra-capsular located or mixed-capsular located (intra-capsular and extra-capsular) and then measured the diameter of each ganglion. After two weeks, we evaluated whether articular cartilage injury existed. The presence of a meniscal tear was also recorded. Results A total of 186 patients (93%) had intra- and extra-capsular ganglia. Intra-capsular ganglia were found in 183 cases (91%) and mixed-capsular ganglia were found in 16 cases (8%). In cases with intra- and extra-capsular ganglia, more meniscal tears were found ( P = 0.029). Intra-capsular ganglia showed more meniscal tears ( P = 0.021). Intra-capsular ganglia were more likely to have high-grade OA ( P = 0.043). Patients who had a meniscal tear displayed larger-sized ganglia, especially of the intra-capsular type ( P = 0.044). Conclusion Patients with intra- and extra-capsular ganglia, especially of the intra-capsular type, are more likely to have meniscal injury and more severe OA. Patients with a meniscal tear or OA are more likely to have larger intra- and extra-capsular ganglia, especially of the intra-capsular type.

Protein Expression in the Gastrocnemius Muscle of a Rodent Shrapnel-Injury Model

With shrapnel injuries, the metal fragment is usually left in place to reduce the risk of morbidity extensive surgery might bring. This means the individual may retain those metals for the remainder of their life. Often the long-term health effects of the embedded metal are not known, especially with respect to protein damage and perturbations of muscle repair pathways. In this study, using homogenates of rat gastrocnemius muscle implanted with pellets of military-relevant metals, we investigated expression of iNOS and eNOS, enzymes involved in nitric oxide production, as well as MMP-2 and MMP-9, matrix metalloproteinases associated with muscle repair. In addition, hydroxynonenal-modified proteins were investigated to assess metal-induced oxidative damage and metal levels in the gastrocnemius determined. Metals were implanted for up to 12 months in order to determine the long-term effects on the expression of muscle-associated proteins. With the exception of iron and cobalt at 1-month post-implantation, there were no significant differences in metal levels in the gastrocnemius in any of the cohorts. Protein expression analysis showed significant decreases in iNOS and eNOS in the 6-month and 12-month lead and depleted uranium groups. Hydroxynonenal-modified proteins were also significantly increased in the iron, copper, lead, and depleted uranium groups. These results suggest that some embedded metals can induce long-term oxidative damage, as well as affect enzyme systems involved in signal transduction.

Exercise Preconditioning Blunts Early Atrogenes Expression and Atrophy in Gastrocnemius Muscle of Hindlimb Unloaded Mice

A large set of FoxOs-dependent genes play a primary role in controlling muscle mass during hindlimb unloading. Mitochondrial dysfunction can modulate such a process. We hypothesized that endurance exercise before disuse can protect against disuse-induced muscle atrophy by enhancing peroxisome proliferator-activated receptor-γ coactivator-1α (PGC1α) expression and preventing mitochondrial dysfunction and energy-sensing AMP-activated protein kinase (AMPK) activation. We studied cross sectional area (CSA) of muscle fibers of gastrocnemius muscle by histochemistry following 1, 3, 7, and 14 days of hindlimb unloading (HU). We used Western blotting and qRT-PCR to study mitochondrial dynamics and FoxOs-dependent atrogenes’ expression at 1 and 3 days after HU. Preconditioned animals were submitted to moderate treadmill exercise for 7 days before disuse. Exercise preconditioning protected the gastrocnemius from disuse atrophy until 7 days of HU. It blunted alterations in mitochondrial dynamics up to 3 days after HU and the expression of most atrogenes at 1 day after disuse. In preconditioned mice, the activation of atrogenes resumed 3 days after HU when mitochondrial dynamics, assessed by profusion and pro-fission markers (mitofusin 1, MFN1, mitofusin 2, MFN2, optic atrophy 1, OPA1, dynamin related protein 1, DRP1 and fission 1, FIS1), PGC1α levels, and AMPK activation were at a basal level. Therefore, the normalization of mitochondrial dynamics and function was not sufficient to prevent atrogenes activation just a few days after HU. The time course of sirtuin 1 (SIRT1) expression and content paralleled the time course of atrogenes’ expression. In conclusion, seven days of endurance exercise counteracted alterations of mitochondrial dynamics and the activation of atrogenes early into disuse. Despite the normalization of mitochondrial dynamics, the effect on atrogenes’ suppression died away within 3 days of HU. Interestingly, muscle protection lasted until 7 days of HU. A longer or more intense exercise preconditioning may prolong atrogenes suppression and muscle protection.

Stevioside Attenuates Insulin Resistance in Skeletal Muscle by Facilitating IR/IRS-1/Akt/GLUT 4 Signaling Pathways: An In Vivo and In Silico Approach

Type-2 diabetes mellitus (T2DM), the leading global health burden of this century majorly develops due to obesity and hyperglycemia-induced oxidative stress in skeletal muscles. Hence, developing novel drugs that ameliorate these pathological events is an immediate priority. The study was designed to analyze the possible role of Stevioside, a characteristic sugar from leaves of Stevia rebaudiana (Bertoni) on insulin signaling molecules in gastrocnemius muscle of obesity and hyperglycemia-induced T2DM rats. Adult male Wistar rats rendered diabetic by administration of high fat diet (HFD) and sucrose for 60 days were orally administered with SIT (20 mg/kg/day) for 45 days. Various parameters were estimated including fasting blood glucose (FBG), serum lipid profile, oxidative stress markers, antioxidant enzymes and expression of insulin signaling molecules in diabetic gastrocnemius muscle. Stevioside treatment improved glucose and insulin tolerances in diabetic rats and restored their elevated levels of FBG, serum insulin and lipid profile to normalcy. In diabetic gastrocnemius muscles, Setvioside normalized the altered levels of lipid peroxidase (LPO), hydrogen peroxide (H2O2) and hydroxyl radical (OH*), antioxidant enzymes (CAT, SOD, GPx and GSH) and molecules of insulin signaling including insulin receptor (IR), insulin receptor substrate-1 (IRS-1) and Akt mRNA levels. Furthermore, Stevioside enhanced glucose uptake (GU) and oxidation in diabetic muscles by augmenting glucose transporter 4 (GLUT 4) synthesis very effectively in a similar way to metformin. Results of molecular docking analysis evidenced the higher binding affinity with IRS-1 and GLUT 4. Stevioside effectively inhibits oxidative stress and promotes glucose uptake in diabetic gastrocnemius muscles by activating IR/IRS-1/Akt/GLUT 4 pathway. The results of the in silico investigation matched those of the in vivo study. Hence, Stevioside could be considered as a promising phytomedicine to treat T2DM.

USE OF A COMBINATION OF TWO IPSILATERAL FLAPS TO COVER POST TRAUMATIC LEG DEFECTS

INTRODUCTION-With advancement in the microsurgical techniques the free tissue transfer has become the rst choice to manage large leg defects which cannot be covered with a local ap.The other option is the cross leg ap.Free aps need an expert team, expensive instruments and plenty of time. Cross leg aps lead to a difcult postoperative period for the patient. When the tissues surrounding the defect are healthy and a careful planning is done, a combination of two local aps which are otherwise used singly for smaller defects may obviate the need for a free or cross leg ap in certain cases.In this study we evaluated the patients who had undergone a combination of gastrocnemius muscle and fasciocutaneous aps for covering the large leg defects. AIMS AND OBJECTIVES-The aim is to study the role of a combination of two local aps to provide cover for the large leg defects. MATERIAL AND METHODS-A retrospective analysis of 30 patients operated from June 2016 to July 2021 for the leg defects rd involving the upper 2/3 of the leg was done.In these patients the upper half of the defects was covered with gastrocnemius muscle ap and the lower half was covered with inferiorly based fasciocutaneous ap. All patients had been followed till the wound cover became stable. RESULTS-All patients were males between the age group of 16 to 46 years. Leg defects were exposed tibia or implant and were post-traumatic in all the cases. Size of the defects ranged from 16cm to 18cm. In all the patients both aps survived well. Two patients had marginal necrosis of fasciocutaneous ap and one had discharge from underneath the muscle ap but were managed conservatively. CONCLUSION- A combination of gastrocnemius muscle and fasciocutaneous aps is a safeoption for covering large leg rd defects involving the upper 2/3 where surrounding skin and muscles are healthy

Influence of water concentration on the content of protein and nucleic acids in organs of chick embryos of different ages

The study was carried out in 10-, 14-15-, 18-20-day-old embryos and 1-2-day-old chickens of the Hy-Line breed. In chickens during embryogenesis, the peculiarities of the relationship between the main indicator of the ontogenetic growth of organs and tissues - the content of intracellular water by previously measured values: with the concentration of protein and nucleic acids in the organs of chicken embryos of different ages - were assessed. It was found that in the period of 10-19 days of embryogenesis, the growth of organs is accompanied by a significant decrease in water content to varying degrees: noticeably higher in the liver and in the cerebral hemispheres - up to 14 days; from the 19th day, these changes are less pronounced. The results of the studied indicator in the muscles indicate advanced embryonic development with a more pronounced decrease in the water content in the red oxidative muscles in comparison with white muscles, where the decrease in the indicator is less pronounced. Key words: chicken embryos, protein, nucleic acid, water content, pectoralis alba and gastrocnemius muscle.