Resveratrol relieves HFD-induced insulin resistance in skeletal muscle tissue through antioxidant capacity enhancement and the Nrf2-Keap1 signaling pathway.

BACKGROUND: Resveratrol has received much attention due to its beneficial effects including antioxidant activity. The purpose of this study was to investigate the therapeutic effects of resveratrol treatment on oxidative stress and insulin resistance in the skeletal muscle of high-fat diet (HFD)-fed animals. METHODS AND RESULTS: A total of 30 six-week-old C57BL/6J mice were randomly allocated to three groups (10 animals in each group): The control group in which mice were fed a normal chow diet (NCD); the HFD group in which mice were fed an HFD for 26 weeks; and the HFD-resveratrol group in which HFD was replaced by a resveratrol supplemented-HFD (400 mg/kg diet) after 10 weeks of HFD feeding. At the end of this period, gastrocnemius muscle samples were examined to determine insulin resistance and the oxidative status in the presence of HFD and resveratrol. Resveratrol supplementation in HFD-fed mice reduced body and adipose tissue weight, improved insulin sensitivity, and decreased oxidative stress as indicated by lower malonaldehyde (MDA) levels and higher total antioxidant capacity. The supplement also increased the expression and activity of antioxidative enzymes in gastrocnemius muscle and modulated Nrf2 and Keap1 expression levels. CONCLUSIONS: These results suggest that resveratrol is effective in improving the antioxidant defense system of the skeletal muscle in HFD-fed mice, indicating its therapeutic potential to combat diseases associated with insulin resistance and oxidative stress.

Effects of gait retraining using minimalist shoes on the medial gastrocnemius muscle-tendon unit behavior and dynamics during running.

The effects of a 12-week gait retraining program on the adaptation of the medial gastrocnemius (MG) and muscle-tendon unit (MTU) were investigated. 26 runners with a rearfoot strike pattern (RFS) were randomly assigned to one of two groups: gait retraining (GR) or control group (CON). MG ultrasound images, marker positions, and ground reaction forces (GRF) were collected twice during 9 km/h of treadmill running before and after the intervention. Ankle kinetics and the MG and MTU behavior and dynamics were quantified. Runners in the GR performed gradual 12-week gait retraining transitioning to a forefoot strike pattern. After 12-week, (1) ten participants in each group completed the training; eight participants in GR transitioned to non-RFS with reduced foot strike angles; (2) MG fascicle contraction length and velocity significantly decreased after the intervention for both groups, whereas MG forces increased after intervention for both groups; (3) significant increases in MTU stretching length for GR and peak MTU recoiling velocity for both groups were observed after the intervention, respectively; (4) no significant difference was found for all parameters of the series elastic element. Gait retraining might potentially influence the MG to operate at lower fascicle contraction lengths and velocities and produce greater peak forces. The gait retraining had no effect on SEE behavior and dynamics but did impact MTU, suggesting that the training was insufficient to induce mechanical loading changes on SEE behavior and dynamics.

Aerobic Exercise Modulates Proteomic Profiles in Gastrocnemius Muscle of db/db Mice, Ameliorating Sarcopenia.

Type-2 diabetes mellitus (T2DM)-induced sarcopenia is intertwined with diminished insulin sensitivity and extracellular matrix (ECM) remodeling in skeletal muscle and other organs. Physical activities such as aerobic exercise play a crucial role in regulating blood glucose levels, insulin sensitivity, metabolic pathways, oxidative stress, fibrosis, ECM remodeling, and muscle regeneration by modulating differentially expressed protein (DEP) levels. The objectives of our research were to investigate the effect of six weeks of aerobic exercise on the gastrocnemius and soleus muscle of db/db mice's DEP levels compared to those of sedentary db/db mice. A total of eight db/db mice were divided into two groups (n = 4 per group), namely sedentary mice (SED) and exercise-trained mice (ET), of which the latter were subjected to six weeks of a moderate-intensity aerobic exercise intervention for five days per week. After the exercise intervention, biochemical tests, including analyses of blood glucose and HbA1c levels, were performed. Histological analysis using H & E staining on tissue was performed to compare morphological characters. Gastrocnemius and soleus muscles were dissected and processed for proteomic analysis. Data were provided and analyzed based on the DEPs using the label-free quantification (LFQ) algorithm. Functional enrichment analysis and Ingenuity Pathway Analysis (IPA) were employed as bioinformatics tools to elucidate the molecular mechanisms involved in the DEPs and disease progression. Significantly reduced blood glucose and HbA1c levels and an increased cross-sectional area (CSA) of gastrocnemius muscle fibers were seen in the ET group after the exercise interventions due to upregulations of metabolic pathways. Using proteomics data analysis, we found a significant decrease in COL1A1, COL4A2, ENG, and LAMA4 protein levels in the ET gastrocnemius, showing a significant improvement in fibrosis recovery, ECM remodeling, and muscle regeneration via the downregulation of the TGF-ß signaling pathway. Upregulated metabolic pathways due to ET-regulated DEPs in the gastrocnemius indicated increased glucose metabolism, lipid metabolism, muscle regeneration, and insulin sensitivity, which play a crucial role in muscle regeneration and maintaining blood glucose and lipid levels. No significant changes were observed in the soleus muscle due to the type of exercise and muscle fiber composition. Our research suggests that engaging in six weeks of aerobic exercise may have a positive impact on the recovery of T2DM-induced sarcopenia, which might be a potential candidate for mitigation, prevention, and therapeutic treatment in the future.

(-)-epicatechin treatment did not modify the thermogenic pathway in the gastrocnemius muscle of male rat offspring obeses by programming.

The aim of this study was to analyse the expression of genes related to the regulation of energy metabolism in skeletal muscle tissue by comparing male offspring in two age groups [at 110 and 245 postnatal days (pnd)] from a mother with obesity induced by a high-fat diet and (-)-epicatechin (Epi) administration. Four groups of six male offspring from different litters were randomly selected for the control groups [C and offspring of mothers with maternal obesity (MO)] or Epi intervention groups. We evaluated the effect of Epi on gastrocnemius tissue by analysing the mRNA and protein expression levels of Fndc5/irisin, Pgc-1α, Ucp3, and Sln. Epi significantly increased the Pgc-1α protein in the MO group of offspring at 110 pnd (p < 0.036, MO vs. MO+Epi), while at 245 pnd, Epi increased Fndc5/irisin mRNA expression in the MO+Epi group versus the MO group (p = 0.006).No differences were detected in Fndc5/irisin, Ucp3 or Sln mRNA or protein levels (including Pgc-1α mRNA) in the offspring at 110 pnd or in Pgc-1α, Ucp3, or Sln mRNA or protein levels (including Fndc5/irisin protein) at 245 pnd among the experimental groups. In conclusion, (-)-epicatechin treatment increased Fndc5/irisin mRNA expression and Pgc-α protein levels in the gastrocnemius muscle of offspring at postnatal days 110 and 245. Furthermore, it is suggested that the flavonoid effect in a model of obesity and its impact on thermogenesis in skeletal muscle are regulated by a different pathway than Fndc5/irisin.

Bilateral Gastrocnemius Muscle Flap for Bilateral Defects of Knee Joint in Schatzker Type V & VI Proximal Tibial Condyle Fractures.

Bilateral defects around the knee joint following fracture of the proximal tibia (Schatzker type V & VI) are difficult to reconstruct because of the unavailability of local tissue. A bicondylar proximal tibial fracture requires a bilateral approach and dual plates for fracture fixation. Because of extensive dissection during plating and extended zone of trauma, the suture lines occasionally dehisce resulting in soft tissue defects on both sides of the proximal tibia. Because of its bilateral nature, the defect requires 2 flaps. We are reporting 2 cases of suture dehiscence after fixation of bicondylar fracture of the proximal tibia which required reconstruction with bilateral gastrocnemius flaps. This reconstruction is a simple option that helps in providing stable coverage. The first case was followed up for a period of 5 years and the second case was followed up for a minimum period of 6 months. Both cases demonstrated well-healed flaps, united bone and no donor side morbidity. Bilateral gastrocnemius muscle flaps can be used simultaneously for 2 separate defects on both sides of the knee without significant donor site morbidly. This reconstructive option provides stable coverage, reduces the infection and promotes bony union thus helping in early ambulation.

Il est difficile de reconstruire des anomalies bilatérales autour de l'articulation du genou après une fracture du tibia proximal (classification de Schatzker de types V et VI) à cause de l'absence de tissus locaux. Il faut une approche bilatérale pour soigner une fracture des plateaux du tibia proximal et deux plaques pour fixer la fracture. En raison de la dissection importante pendant l'installation des plaques et de la zone étendue du traumatisme, il arrive que les lignes de suture s'ouvrent, ce qui entraîne des anomalies des tissus mous des deux côtés du tibia proximal. Parce qu'elle est bilatérale, l'anomalie doit être corrigée par deux lambeaux. Les chercheurs rendent compte de deux cas de déhiscence des sutures après la fixation d'une fracture des plateaux du tibia proximal qui a dû être reconstruite par des lambeaux bilatéraux du muscle gastrocnémien. Cette reconstruction est une option simple qui contribue à une couverture stable. Le premier cas a été suivi pendant une période de cinq ans et le deuxième, pendant une période minimale de six mois. Dans les deux cas, les lambeaux ont bien guéri, l'os s'est uni et il n'y avait pas de morbidité au site du donneur. Il est possible d'utiliser simultanément les lambeaux bilatéraux du muscle gastrocnémien pour corriger deux anomalies distinctes des deux côtés du genou sans provoquer de morbidité importante au site du donneur. Cette possibilité reconstructive assure une couverture stable, réduit l'infection, favorise l'union osseuse et contribue donc à une ambulation précoce.

Both acute glyphosate and the aminomethylphosphonic acid intoxication decreased the acetylcholinesterase activity in rat hippocampus, prefrontal cortex and gastrocnemius muscle.

It has been reported that glyphosate, one of the most common herbicides used in agriculture, impairs locomotion and cognition. Glyphosate has a variable half-life in soil up to biotic and/or abiotic factors transform the molecule in metabolites such as the aminomethylphosphonic acid (AMPA) that has a longer half-life. In this study, female Sprague Dawley rats were acutely exposed to different doses of glyphosate or AMPA (i.e. 10, 56 or 100 mg/kg) and, subsequently, the acetylcholinesterase (AChE) activity was measured in the hippocampus, prefrontal cortex (PFC) and the gastrocnemius muscle. Both glyphosate and AMPA produced a similar decrease in the AChE activity in all the tissues tested. These results suggest that interference with normal cholinergic neurotransmission may be one of the mechanisms involved in glyphosate-induced motor alterations in rats. Moreover, our results highlight the biological importance of AMPA as a molecule with anticholinesterase action in brain and skeletal muscle. To our knowledge, this is the first report showing in vivo that AMPA, the major metabolite of glyphosate, behaves as an organophosphate.

Fatty infiltration of gastrocnemius-soleus muscle complex: Considerations for myosteatosis rehabilitation.

Although previous studies have reported fatty infiltration of the gastrocnemius-soleus complex, little is known about the volumetric distribution and patterns of fatty infiltration. The purpose of this anatomical study was to document and quantify the frequency, distribution, and pattern of fatty infiltration of the gastrocnemius-soleus complex. One hundred formalin-embalmed specimens (mean age 78.1 ± 12.3 years; 48F/52M) were serially dissected to document the frequency, distribution, and pattern of fatty infiltration in the medial and lateral heads of gastrocnemius and soleus muscles. Fatty infiltration was found in 23% of specimens, 13 unilaterally (8F/5M) and 10 (5M/5F) bilaterally. The fatty infiltration process was observed to begin medially from the medial aspect of the medial head of gastrocnemius and medial margin of soleus and then progressed laterally throughout the medial head of gastrocnemius and the marginal, anterior, and posterior soleus. The lateral head of gastrocnemius remained primarily muscular in all specimens. Microscopically, the pattern of infiltration was demonstrated as intramuscular with intact aponeuroses, and septa. The remaining endo-, peri-, and epimysium preserved the overall contour of the gastrocnemius-soleus complex, even in cases of significant fatty replacement. Since the external contour of the calf is preserved, the presence of fatty infiltration may be underdiagnosed in the clinic without imaging. Myosteatosis is associated with gait and balance challenges in the elderly, which can impact quality of life and result in increased risk of falling. The findings of the study have implications in the rehabilitation management of elderly patients with sarcopenia and myosteatosis.

Oyster (Ostrea Plicatula Gmelin) Peptides Improve Exercise Endurance Capacity via Activating AMPK and HO-1.

Objective: Previous studies have shown that oyster peptides (OPs) have antioxidant and anti-fatigue activities. This study aimed to investigate the effects of OPs on swimming endurance in mice and the underlying mechanisms.Methods: The mice were subjected to gavage with OPs and subjected to exercise training. After 14 days, various biochemical indicators in the blood and gastrocnemius muscle of mice were assessed, and real-time PCR was utilized to detect the level of signal pathway regulation by OPs in the gastrocnemius muscle. Molecular docking technology was employed to observe the potential active components in OPs that regulate signal pathways.Results: In this study, OPs supplementation combined with and without exercise significantly extended swimming time compared to the sedentary group. OPs supplementation with exercise also increased glycogen levels and decreased blood urea nitrogen, lactate dehydrogenase, and lactic acid levels. Additionally, mice in the exercise with OPs group exhibited higher activities of antioxidant enzymes. OPs can upregulate metabolic regulatory factors such as AMP-activated protein kinase, peroxisome proliferator-activated receptor gamma coactivator-1 alpha, peroxisome proliferator-activated receptor delta, and glucose transporter 4, thereby increasing energy supply during exercise. Additionally, OPs enhances the expression of heme oxygenase 1 and superoxide dismutase 2, thereby reducing oxidative stress during physical activity. Molecular docking analyses revealed that peptides found in OPs formed hydrogen bonds with AMPK and HO-1, indicating that they can exert bioactivity by activating target proteins such as AMPK and HO-1.Conclusions: OPs supplementation improved energy reserves, modulated energy metabolism pathways, and coordinated antioxidative stress responses, ultimately enhancing swimming endurance. These findings suggest that OPs have the potential to improve exercise levels by promoting metabolism and improving energy utilization efficiency.

Quantitative study of the popliteal fossa in the human fetus.

The popliteal fossa presents an extensive diamond-shaped topographical element on the posterior aspect of the knee. With the use of classical anatomical dissection, digital image analysis of NIS Elements AR 3.0 and statistics we morphometrically analyzed the size of the popliteal fossa in human fetuses aged 17-29 weeks of gestation. Morphometric parameters of the popliteal fossa increased logarithmically with fetal age: y = -44.421 + 24.301 × ln (Age) for length of superomedial boundary, y = -41.379 + 22.777 × ln (Age) for length of superolateral boundary, y = -39.019 + 20.981 × ln (Age) for inferomedial boundary, y = -37.547 + 20.319 × ln (Age), for length of inferolateral boundary, y = -28.915 + 15.822 × ln (Age) for transverse diameter, y = -69.790 + 38.73 × ln (Age) for vertical diameter and y = -485.631 + 240.844 × ln (Age) for projection surface area. Out of the four angles of the popliteal fossa the medial one was greatest, the inferior one the smallest, while the lateral one was somewhat smaller than the medial one and approximately three times greater than the superior one, with no difference with fetal age. In terms of morphometric parameters the popliteal fossa in the human fetus displays neither male-female nor right-left differences. In the popliteal fossa, growth patterns of its four boundaries, vertical and transverse diameters, and projection surface area all follow natural logarithmic functions. All the morphometric data is considered age-specific reference intervals, which may be conducive in the diagnostics of congenital abnormalities in the human fetus.

iMS-Bmal1-/- mice show evident signs of sarcopenia that are counteracted by exercise and melatonin therapies.

Sarcopenia is an age-related disease characterized by a reduction in muscle mass, strength, and function and, therefore, a deterioration in skeletal muscle health and frailty. Although the cause of sarcopenia is still unknown and, thus, there is no treatment, increasing evidence suggests that chronodisruption, particularly alterations in Bmal1 clock gene, can lead to those deficits culminating in sarcopenia. To gain insight into the cause and mechanism of sarcopenia and the protective effect of a therapeutic intervention with exercise and/or melatonin, the gastrocnemius muscles of male and female skeletal muscle-specific and inducible Bmal1 knockout mice (iMS-Bmal1-/- ) were examined by phenotypic tests and light and electron microscopy. Our results revealed a disruption of the normal activity/rest rhythm, a drop in skeletal muscle function and mass, and increased frailty in male and female iMS-Bmal1-/- animals compared to controls. A reduction in muscle fiber size and increased collagenous tissue were also detected, accompanied by reduced mitochondrial oxidative capacity and a compensatory shift towards a more oxidative fiber type. Electron microscopy further supports mitochondrial impairment in mutant mice. Melatonin and exercise ameliorated the damage caused by loss of Bmal1 in mutant mice, except for mitochondrial damage, which was worsened by the latter. Thus, iMS-Bmal1-/- mice let us to identify Bmal1 deficiency as the responsible for the appearance of sarcopenia in the gastrocnemius muscle. Moreover, the results support the exercise and melatonin as therapeutic tools to counteract sarcopenia, by a mechanism that does not require the presence of Bmal1.

Azilsartan prevents muscle loss and fast- to slow-twitch muscle fiber shift in natural ageing sarcopenic rats.

Sarcopenia is a musculoskeletal disease that reduces muscle mass and strength in older individuals. The study investigates the effects of azilsartan (AZL) on skeletal muscle loss in natural sarcopenic rats. Male Sprague-Dawley rats aged 4-6 months and 18-21 months were selected as young-matched control and natural-aged (sarcopenic) rats, respectively. Rats were allocated into young and old control (YC and OC) and young and old AZL treatment (YT and OT) groups, which received vehicles and AZL (8 mg/kg, orally) for 6 weeks. Rats were then sacrificed after muscle function analysis. Serum and gastrocnemius (GN) muscles were isolated for further endpoints. AZL significantly improved muscle grip strength and antioxidant levels in sarcopenic rats. AZL also restored the levels of insulin, testosterone, and muscle biomarkers such as myostatin and creatinine kinase in sarcopenic rats. Furthermore, AZL treatment improved the cellular and ultrastructure of GN muscle and prevented the shift of type II (glycolytic) myofibers to type I (oxidative) myofibers. The results showed that AZL intervention restored protein synthesis in natural sarcopenic rats by increasing p-Akt-1 and decreasing muscle RING-finger protein-1 and tumor necrosis factor alpha immunoexpressions. In conclusion, the present findings showed that AZL could be an effective intervention in treating age-related muscle impairments.

Morphological variability of the leg muscles: potential traps on ultrasound that await clinicians.

BACKGROUND: Although muscles and their tendons are not considered the most morphologically variable structures, they still manifest a substantial diversity of variants. The aim of this study is to increase awareness of some of the many possible variants found during ultrasound imaging of one lower limb compartment, the leg, that could potentially mislead clinicians and lead to misdiagnosis. MATERIALS AND METHODS: PubMed was used for a comprehensive literature search for morphological variations. Relevant papers were included, and citation tracking was used to identify further publications. RESULTS: Several morphological variants of muscles of the leg have been described over many years, but this study shows that the occurrence of further variations in ultrasound imaging requires further investigations. CONCLUSIONS: The incidence of additional structures including muscles and tendons during ultrasound examination can cause confusion and lead to misinterpretation of images, misdiagnosis, and the introduction of unnecessary and inappropriate treatments.

Effects of electroacupuncture at "Jiaji" (EX-B 2) combined with neurodynamic mobilization on gastrocnemius muscle atrophy and expression of NF-κB and MuRF1 in rabbits after sciatic nerve injury. / 电针"夹脊"ç»“åˆç¥žç»æ¾åŠ¨æœ¯å¯¹åéª¨ç¥žç»æŸä¼¤å ”è “è‚ è‚ŒèŽç¼©åŠNF-κB、MuRF1表达的影响.

OBJECTIVES: To observe the effects of electroacupuncture (EA) at "Jiaji" (EX-B 2) combined with neurodynamic mobilization (NM) on the cross-sectional area of the gastrocnemius muscle fibers after sciatic nerve injury in rabbits, and the expression of nuclear factor κB (NF-κB) and muscle-specific ring-finger protein 1 (MuRF1). METHODS: A total of 180 common-grade New Zealand rabbits (half male and half female) were randomly divided into five groups, i.e. a normal control group, a model control group, a NM group, an EA group and a combined intervention group, 36 rabbits in each group. Except in the normal control group, clipping method was used to prepare the model of sciatic nerve injury in the rest groups. On the 3rd day of successful modeling, NM was delivered in the NM group. In the EA group, EA was exerted at bilateral "Jiaji" (EX-B 2) of L4 to L6, stimulated with disperse-dense wave and the frequency of 2 Hz/100 Hz. In the combined intervention group, after EA delivered at bilateral "Jiaji" (EX-B 2) of L4 to L6 , NM was operated. The intervention in each group was delivered once daily, for 6 days a week, and lasted 1, 2 or 4 weeks according to the collection time of sample tissue. After 1, 2 and 4 weeks of intervention, in each group, the toe tension reflex score and the modified Tarlov test score were observed; the morphology of the gastrocnemius muscle was observed by HE staining and the cross-sectional area of muscular fiber was measured; using Western blot method, the expression of NF-κB and MuRF1 of the gastrocnemius muscle was detected. RESULTS: After 1, 2 and 4 weeks of intervention, the toe tension reflex scores and the modified Tarlov scores in the model control group were lower than those of the normal control group (P<0.05), and these two scores in the NM group, the EA group and the combined intervention group were all higher than those of the model control group (P<0.05); the scores in the combined intervention group were higher than those in the EA group and the NM group (P<0.05). The gastrocnemius fibers were well arranged and the myocyte morphology was normal in the normal control group. In the model control group, the gastrocnemius fibers were disarranged, the myocytes were irregular in morphology and the inflammatory cells were infiltrated in the local. In the NM group, the EA group and the combined intervention group, the muscle fibers were regularly arranged when compared with the model control group. After 1, 2 and 4 weeks of intervention, the cross-sectional areas of the gastrocnemius muscle fibers in the model control group were smaller than those of the normal control group (P<0.05). The cross-sectional areas in the NM group, the EA group and the combined intervention group were larger than those of the model control group (P<0.05), and the cross-sectional areas in the combined intervention group were larger than those in the NM group and the EA group (P<0.05). After intervention for 1, 2 and 4 weeks, the protein expressions of NF-κB and MuRF1 in the gastrocnemius muscle were higher in the model control group in comparison of those in the normal control group (P<0.05). In the NM group, the EA group and the combined intervention group, the expressions of NF-κB after intervention for 1, 2 and 4 weeks and the expressions of MuRF1 after 2 and 4 weeks of intervention were lower when compared with those in the model control group (P<0.05). In the combined intervention group, the protein expressions of NF-κB after intervention for 1, 2 and 4 weeks and the expressions of MuRF1 after 2 and 4 weeks of intervention were decreased when compared with those in the NM group and the EA group (P<0.05). CONCLUSIONS: Electroacupuncture at "Jiaji" (EX-B 2) combined with NM may increase the muscle strength and sciatic function and alleviate gastrocnemius muscle atrophy in the rabbits with sciatic nerve injury. The underlying mechanism is related to the inhibition of NF-κB and MuRF1 expression.

Ultrasound Assessment of the Gastrocnemius Muscle as a Potential Tool for Identifying Sarcopenia in Patients with Type 2 Diabetes.

Objective: This study aims to examine the clinical significance of ultrasound evaluation of the gastrocnemius muscle (GM) in identifying sarcopenia in patients with type 2 diabetes (T2D). Methods: One hundred and fifty-three patients with T2D were included in this study. We measured the appendicular skeletal muscle mass index (ASMI), handgrip strength, and 6-meter walking speed. The US-derived muscle thickness (MT), cross-sectional area (CSA), and shear wave ultrasound elastography (SWE) of GM were also measured. We assessed the correlations between clinical indicators and US features. The model for screening sarcopenia was established using stepwise logistic regression. Stepwise linear regression was used to identify a set of variables that jointly estimated ASMI. The model's ability to identify sarcopenia and low muscle mass was assessed by receiver operating characteristic (ROC) curve analysis. Results: The prevalence of sarcopenia in this study was 24.2%. The CSA, MT and SWE values of the patients with sarcopenia were lower than those of patients without sarcopenia (all p < 0.05). ASMI was positively correlated with CSA (r = 0.56, p < 0.001) and MT (r = 0.39, p < 0.001). Handgrip strength was positively correlated with CSA (r = 0.45, p < 0.001), MT (r = 0.25, p < 0.001), and SWE (r = 0.26, p = 0.002). A diagnostic model for sarcopenia was established with a sensitivity of 81.1%, specificity of 75.0%, and an area under the curve (AUC) of 0.800. The estimated ASMI equation was developed and found to have a positive correlation with actual ASMI (r = 0.70, p < 0.001). It was also effective in diagnosing low muscle mass, with an AUC of 0.787 for males and 0.783 for females. Conclusion: Ultrasonographic assessment of the gastrocnemius muscle was found to be a useful and convenient method for detecting sarcopenia in patients with T2D.

Popliteal Artery Entrapment Syndrome Presented with Popliteal Artery Pseudoaneurysm: A Case Report.

Popliteal artery entrapment syndrome (PAES) is a rare vascular disorder characterized by the compression of the popliteal artery behind the knee, primarily affecting physically active individuals. This is a case of a 36-year-old man who presented with a 1-week history of sudden-onset left leg pain. Diagnostic evaluation, including physical examination, color duplex ultrasonography, computed tomography, and magnetic resonance imaging, revealed a popliteal artery pseudoaneurysm caused by type 5 PAES. The patient underwent surgical exploration to release the entrapment, followed by an interposition graft with the ipsilateral great saphenous vein. Patient postoperative recovery was uneventful, with significant symptomatic improvement. This case underscores the significance of considering PAES as a differential diagnosis in young patients with popliteal artery aneurysms and highlights the necessity for prompt diagnosis and treatment to prevent limb-threatening complications.

Effects of tendon elastic energy and electromyographic activity pattern on jumping height and pre-stretch augmentation during jumps with different pre-stretch intensity.

The present study aimed to investigate the effects of tendon elastic energy and electromyographic activity patterns (ratio of pre-landing to concentric: mEMG PLA/CON; ratio of eccentric to concentric; mEMG ECC/CON) on jump performance. Twenty-nine males performed five kinds of unilateral jumps using only ankle joint (no-countermovement jump: noCMJ; countermovement jump: CMJ; drop jumps at 10, 20 and 30 cm drop height: DJ10, DJ20 and DJ30). Jumping height, pre-stretch augmentation and electromyographic activity of the plantar flexor muscles were measured. The elastic energy of the Achilles tendon was measured during isometric contractions. Relative tendon elastic energy (to body mass) was highly correlated with jumping heights of CMJ, DJ10 and DJ20 but not with noCMJ and DJ30, whereas that was significantly correlated with pre-stretch augmentation in CMJ, but not with three DJs. The mEMG PLA/CON was significantly correlated with the pre-stretch augmentation of DJ20 and DJ30, but not with DJ10, whereas the mEMG ECC/CON was significantly correlated with the pre-stretch augmentation of DJ20 and DJ30, but not with CMJ and DJ10. These results suggested that jumping exercises with low pre-stretch intensity benefited from tendon elastic energy, but those with high pre-stretch intensity benefited from electromyographic activity patterns.

[Effects of electroacupuncture on gait and proliferation and differentiation of muscle satellite cell in rats with acute blunt trauma of gastrocnemius muscle].

OBJECTIVE: To observe the effects of electroacupuncture on threshold of pain, gait, proliferation and differentiation of muscle satellite cell in rats with acute blunt trauma of gastrocnemius muscle, and to explore the possible mechanism of electroacupuncture in promoting the repair of acute injury of skeletal muscle. METHODS: A total of 48 SD rats were randomly divided into a blank group (6 rats), a model group (24 rats) and an electroacupuncture group (18 rats). In the model group and the electroacupuncture group, the model of acute blunt trauma of gastrocnemius muscle was established by self-made impactor. In the electroacupuncture group, electroacupuncture was applied at "Chengshan" (BL 57) and "Yanglingquan" (GB 34) on the right side, with disperse-dense wave, in frequency of 2 Hz/100 Hz, once a day, 30 min each time. Electroacupuncture intervention was performed for 3, 7 and 14 days according to the sampling time. On the 1st, 3rd, 7th and 14th days after modeling, the mechanical withdrawal pain threshold of hindfoot was detected by Von Frey method; the standing time and the maximum contact area of the right hindfoot were recorded by Cat Walk XTTM animal gait analysis instrument; the morphology of the right gastrocnemius muscle and the number of inflammatory cells were observed by HE staining; the positive expression of paired box gene 7 (Pax7) and myogenic differentiation (MyoD) of the right gastrocnemius muscle was detected by immunofluorescence. RESULTS: After modeling, the muscle fiber rupture and massive infiltration of red blood cells and inflammatory cells were observed in the right gastrocnemius muscle; after electroacupuncture intervention, the morphology of muscle fiber was intact and the infiltration of inflammatory cells was improved. Compared with the blank group, in the model group, the differences of mechanical withdrawal pain threshold between the left and right foot were increased (P<0.05), the standing time was shortened and the maximum contact area of the right hindfoot was decreased (P<0.05), the number of inflammatory cells and the positive expression of Pax7 and MyoD of the right gastrocnemius muscle were increased (P<0.05) on the 1st, 3rd, 7th and 14th days after modeling. Compared with the model group, in the electroacupuncture group, the differences of mechanical withdrawal pain threshold were decreased (P<0.05), the standing time was prolonged (P<0.05), the number of inflammatory cells of right gastrocnemius muscle was decreased (P<0.05) on the 7th and 14th days after modeling; the maximum contact area of the right hindfoot was increased (P<0.05), the positive expression of MyoD of the right gastrocnemius muscle was increased (P<0.05) on the 3rd, 7th and 14th days after modeling; the positive expression of Pax7 of the right gastrocnemius muscle was increased (P<0.05) on the 3rd day after modeling. CONCLUSION: Electroacupuncture can effectively improve the pain threshold and gait in rats with acute blunt trauma of gastrocnemius muscle, and promote the repair of skeletal muscle injury, the mechanism may be related to the up-regulation of Pax7 and MyoD, so as to promoting the proliferation and differentiation of muscle satellite cell.

Low-Level Photobiomodulation Therapy Modulates H2O2 Production, TRPC-6, and PGC-1α Levels in the Dystrophic Muscle.

Objective: This study evaluated photobiomodulation therapy (PBMT) effects on the factors involved in mitochondrial biogenesis, on the mitochondrial respiratory complexes, and on the transient receptor potential canonical channels (such as TRPC-1 and TRPC-6) in in vitro (mdx muscle cells) and in vivo studies (gastrocnemius muscle) from mdx mice, the dystrophin-deficient model of Duchenne muscular dystrophy (DMD). Background: There is no successful treatment for DMD, therefore demanding search for new therapies that can improve the muscle role, the quality of life, and the survival of dystrophic patients. Methods: The dystrophic primary muscle cells received PBMT at 0.6 J and 5 J, and the dystrophic gastrocnemius muscle received PBMT at 0.6 J. Results: The dystrophic muscle cells treated with PBMT (0.6 J and 5 J) showed no cytotoxicity and significantly lower levels in hydrogen peroxide (H2O2) production. We also demonstrated, for the first time, the capacity of PBMT, at a low dose (0.6 J), in reducing the TRPC-6 content and in raising the peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α) content in the dystrophic gastrocnemius muscle. Conclusions: PBMT modulates H2O2 production, TRPC-6, and PGC-1α content in the dystrophic muscle. These results suggest that laser therapy could act as an auxiliary therapy in the treatment of dystrophic patients.

Do the fasciae of the soleus have a role in plantar fasciitis?

Plantar fasciitis is a chronic, self-limiting, and painful disabling condition affecting the inferomedial aspect of the heel, usually extending toward the metatarsophalangeal joints. There is compelling evidence for a strong correlation between Achilles tendon (AT) loading and plantar aponeurosis (PA) tension. In line with this, tightness of the AT is found in almost 80% of patients affected by plantar fasciitis. A positive correlation has also been reported between gastrocnemius-soleus tightness and heel pain severity in this condition. Despite its high prevalence, the exact etiology and pathological mechanisms underlying plantar heel pain remain unclear. Therefore, the aim of the present paper is to discuss the anatomical and biomechanical substrates of plantar fasciitis with special emphasis on the emerging, though largely neglected, fascial system. In particular, the relationship between the fascia, triceps surae muscle, AT, and PA will be analyzed. We then proceed to discuss how structural and biomechanical alterations of the muscle-tendon-fascia complex due to muscle overuse or injury can create the conditions for the onset of PA pathology. A deeper knowledge of the possible molecular mechanisms underpinning changes in the mechanical properties of the fascial system in response to altered loading and/or muscle contraction could help healthcare professionals and clinicians refine nonoperative treatment strategies and rehabilitation protocols for plantar fasciitis.

The Incidence of Gastrocnemius Tightness Among Clinic Staff in a District Hospital's Clinic in the State of Kedah, Malaysia.

Aim Musculus Gastrocnemius Tightness (MGT) has been linked with common foot and ankle pathologies. These symptoms sometimes are not severe enough for the patient to seek treatment. This study aims to determine the incidence rate of MGT among our clinical personnel and if there is any association between foot and ankle symptoms with MGT. Materials and methods This observational cross-sectional study involves clinical personnel from our Specialist Clinics at Hospital Kulim, Malaysia. We interviewed and assessed 85 volunteers of which, we measured the passive ankle dorsiflexion of the volunteers (the Silfverskiöld) test, to diagnose MGT. We then used the Manchester Oxford Foot Questionnaire (MOxFQ) is used to determine the functional outcome of our volunteers. Results Out of a total of 85 volunteers assessed, 12 (14%) volunteers were found to have gastrocnemius tightness. Among this cohort, 11 were symptomatic. Out of the 73 who did not have MGT, there were three symptomatic volunteers. There was a significant association between volunteers with foot and ankle symptoms with gastrocnemius tightness, compared to those without. There was a significant difference in the relationship between the MOxFQ scores in all components (walking, pain, and social) when comparing those with and those without MGT. Conclusion We conclude that there is a significant association between foot and ankle symptoms and MGT in our clinic sample population. However, these symptoms were not severe enough for these symptomatic volunteers to seek treatment. We should consider screening symptomatic staff and implementing stretching protocols.