Muscle Loss in Elderly

Aging is associated with loss of skeletal muscle mass, strength and endurance. The aim of this study was to determinate age related changes in human muscles with different function and location in the body (vastus lateralis muscle and intercostal internus muscle). Our results suggest that age related muscle atrophy affect both human skeletal muscles. Also, the results showed the increase in percentage of muscle fibers with high oxidative activity during aging

Influence of Hyperbaric Oxygen Treatment on Myogenic Transcriptional Factors of Denervated Rat Muscle

The aim of this study was to determine whether hyperbaric oxygen (HBO2) treatment influences the expression of transcriptional myogenic factors in denervated rat’s extensor digitorum longus muscle. Thus, expressing regulatory myogenic factors MyoD and myogenin were analyzed in denervated muscles (up to 30 days). Second group of denervated rats were afterwards treated with HBO2. Normal, innervated muscles were used as controls. Western blot analysis showed a significant upregulation of MyoD and myogenin proteins in denervated muscle during this period. Denervated muscles of rats exposed to HBO2 treatment had also significant upregulation of both transcriptional factors but the treatment had not altered their expression. The immunohistochemical analysis showed MyoD and myogenin protein expression through this period in the denervated, untreated muscles and in denervated muscles of rats treated with HBO2, too. One month denervation caused a reduction in muscle fiber cross-sectional area. The treatment with HBO2 had not reduced the degree of atrophy. The protocol of hyperbaric oxygenation (HBO) applied in this study had no beneficial effect either on transcriptional myogenic factors or on atrophy of denervated rat muscle

Expression of myogenic regulatory factors in rat skeletal muscles after denervation

Aim: The aim of this study was to investigate expression of myogenic regulatory factors MyoD and myogenin during denervation in fast and slow rat skeletal muscles of different rat strains (Wistar and Sprague-Dawely). Material and Methods: Immunohistochemical andWestern blot analyses were performed on tibialis anterior and soleus muscles. Results: Immunohistochemical analysis of tibialis anterior and soleus muscles during denervation demonstrated that both myonuclei and satellite cells were activated.Western blot analysis showed a significant upregulation of MyoD and myogenin proteins in m. tibialis anterior at all time points of denervation, except on 60th day for MyoD. In m. soleus during denervation Western blot analysis showed upregulation of MyoD and myogenin in first 14 days, and there was no expression after that period. Conclusion: Our results indicate that MyoD and myogenin protein expression during denervation is muscle type specific. The role of MyoD and myogenin in adult muscle is potentially also important in orchestrating an adaptive response of existing muscle fibers during denervation

Aging of Human Skeletal Muscles

Normal aging in humans is associated with progressive decrease in skeletal muscle mass and strength (sarcopenia) which contributes to frailty and falls. The age associated changes in body composition result from lower levels of anabolic hormones, oxidative damage, neuromuscular alterations and a general decrease in muscle protein turnover. In this review we discuss the potential mechanisms and physical activity as prevention and treatment of sarcopenia

Muscle progenitor cells in skeletal muscle

Iako su malobrojne, satelitske stanice u skeletnom mišiću mogu u slučaju ozljede proizvesti velik broj mioblasta koji će daljnjim procesom regenerativne miogeneze dovesti do obnove mišićnog tkiva. Ove stanice su matične stanice specifične za mišićno tkivo. Njihovom aktivacijom pokreće se slijed u ekspresiji miogenetskih regulacijskih čimbenika i time program miogeneze. Satelitskim je stanicama svojstvena sposobnost samoobnavljanja. One predstavljaju heterogenu skupinu stanica s obzirom na funkciju i na markere kojima se dokazuju. Pored satelitskih stanica izolirane su i druge matične stanice u mišiću koje u eksperimentalnim uvjetima pridonose miogenezi. Miogenetski potencijal ovih stanica pokušava se iskoristiti u terapeutske svrhe u nekim oblicima mišićnih oboljenja.Although not numerous, satellite cells in skeletal muscle are capable to generate a large number of myoblasts upon injury. A further process of regenerative myogenesis leads to the muscle regeneration. Satellite cells are stem cells specific to skeletal muscle tissue. Their activation initiates the sequence of expression in myogenic regulatory factors and thus myogenic program. Besides the ability to provide new myoblasts, these cells also have selfrenewing capacity. Satellite cells are a heterogeneous group of cells considering their function and distinction markers. Several other types of stem cells with myogenic ability (in experimental conditions) have been isolated from the skeletal muscle. Therapeutic approaches to treat some forms of muscular diseases have been based on myogenic potential of both groups of stem cells

Effect of Hyperbaric Oxygen Treatment on Myogenic Transcriptional Factors in Regenerating Rat Masseter Muscle

Hyperbaric oxygen (HBO) treatment was shown to be beneficial as an additional treatment for ischemic muscles in crush injuries and ischemia-reperfusion injuries. The purpose of this study was to assess the influence of hyperbaric oxygen treatment on transcriptional myogenic factors during muscle regeneration. Those factors (MyoD, myf5, myogenin, mrf4) are essential for determination and differentiation of skeletal muscle tissue and together with several other factors control gene expression during myogenesis. The process of regeneration in rat masseter muscle was provoked with injection of local anesthetic bupivacaine hydrochloride. Following injection, the animals were treated once daily in hyperbaric chamber from one to ten days and than sacrificed. Immunohistochemical and Western blot analysis of frozen masseter muscle samples showed a transient upregulation of myoD and myogenin transcriptional factors in the muscles of hyperbaric oxygen treated rats and of rats that have not been treated after the injury. HBO treatment had no effect on the expression of MyoD and myogenin transcriptional factors in the regenerating rat masseter muscle

The effect of age, anthropometric parameters, vertebral bone densitometry and ash density on iliac crest bone volume and microstructure

Background and Purpose: The purpose was to compare iliac crest bone static bone histomorphometry and vertebral bone densitometry as two methods frequently used in clinical practice. Patients and Methods: Cylindrical bone samples of the iliac crest bone (N=100) for bone histomorphometry and the whole bodies of the third lumbar vertebra (L3) (N=100) for bone densitometry and atomic absorption spectrometry were collected. Multiple regression analyses were carried out and results were considered significant when p<0.05 and 0.01. Results: Age was inversely proportional to all histomorphometric parameters except for Tb.Sp. Age predicted BV/TV with the largest share of contribution of 68%. Gender showed the highest share of contribution for the Tb.Th (32%), while BMD showed it for the Ct.Th (10%). Conclusions: After age and gender, BMD is the third strongest variable to predict iliac crest bone histomorphometric parameters, and thus we can conclude that iliac crest bone histomorphometry and vertebral bone densitometry are correlated, which is important for monitoring osteoporosis in good clinical practic

The craniovertebral venous system

Kraniovertebralni venski sustav čine kranijalne i kralježnične vene. Ove vene su međusobno povezane i nemaju zalistaka, što omogućava tok krvi u oba smjera. Kranijalnim venama pripadaju vene mozga, sinus tvrde moždane ovojnice, diploične i emisarne vene, dok kralježničnim venama pripada vanjski i unutarnji vertebralni splet te bazivertebralne vene. Iz kraniovertebralnog venskog sustava krv odvode vv. vertebrales, vv. intercostales postt., vv. lumbales i v. sacralis lat. u sustave gornje i donje šuplje vene izravno ili putem sustava vene azigos. Kraniovertebralni venski sustav s ostalim sustavima tvori brojne anastomoze koje u patološkim uvjetima predstavljaju kolateralni put krvi ka srcu i omogućuju izravno širenje neoplazmi iz prsne, trbušne i zdjelične šupljine u područje kranijuma i kralježnice. Osim toga, značajna je uloga kranijalnih vena i vena gornjih dijelova dišnog sustava u selektivnom rashlađivanju mozga, što je osobito značajno u hipertermiji.The craniovertebral venous system consists of cranial veins and veins of vertebral column. These veins are interconnected with no valves, allowing blood to flow freely in both directions. The veins of brain, dural venous sinuses, diploic veins and emissary veins belong to cranial veins. The veins of vertebral column consist of external and internal vertebral venous plexus and of basivertebral veins. The vertebral veins, posterior intercostals veins, lumbar veins and lateral sacral veins drain blood directly from craniovertebral venous system in azigos vein or in superior and inferior vena cava. The craniovertebral venous system with other venous systems are forming numerous anastomosis, which in pathological conditions represent a collateral pathway for blood to the heart and allow the direct spread of neoplasms of the thoracic, abdominal and pelvic cavity in the area of the cranium and spine. In addition, the significance of cranial veins and veins of the upper part of the respiratory system are part of the selective brain cooling mechanism which is particulary important in condition of hyperthermia