Immunohistochemical Analysis of the Human Psoas Major Muscle with Regards to the Body Side and Aging

The aim of our study was to explore the age related changes of the fibre type composition of the human psoas major muscle. Moreover, we wanted to compare the fibre type composition of the left and right muscle. Muscle samples were collected from 15 young and 15 old males. Type I, IIA and IIX muscle fibres were typed using myosin heavy chain identification. The serial transverse sections were analysed using a light microscope. Results of our study showed that the age-related atrophy affected all three fibre types. Type IIA fibres were affected most profoundly while type I fibres were affected most weakly. The percentage of the different fibre types did not change during aging. There were no differences in the fibre type composition between the left and right muscle. Human psoas major muscle undergoes normal aging changes with the atrophy of all three fibre types, whereas atrophy most profoundly affects type IIA fibres. No differences in the fibre type composition between the left and right muscle point to the equal engagement of both legs in normal everyday activities of human

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

Reg IV Protein is Expressed in Normal Rat Tissue

The Reg IV gene has been documented in the colon, small intestine, stomach and pancreas of the human. Expression of the Reg IV in different cell types has been associated with regeneration, cell growth and cell survival, cell adhesion and resistance to apoptosis. It is unknown whether the Reg IV protein is present in the normal rat tissue. The aim of this study was to reveal the expression of the Reg IV protein in the rat spleen and colon. Western blot analysis using antibody specific for Reg IV protein were performed on rat spleen and colon extracts. Low level of Reg IV expression was found in all examined colon samples. The expression of Reg IV protein in spleen tissue was significantly higher than in the colon. Reg IV protein was immunohistochemically stained in a few epithelial cells in the basal portion of colon crypts and in a large spleen cells which were scattered in the red pulp. Our results demonstrate for the first time the presence of the Reg IV protein expression in the healthy spleen and colon tissue of the rat. Other members of the Reg family, Reg I and Reg III proteins have been shown to act as a growth factors in gastrointestinal tract, but without further experiments we can only assume the potential role of the Reg IV protein in spleen and colon cell growth

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

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