Jin-Hwan Yoon

Effect of treadmill exercise on Purkinje cell loss and astrocytic reaction in the cerebellum after traumatic brain injury

The cerebellum is one of the brain areas, which is selectively vulnerable to forebrain traumatic brain injuries (TBI). Physical exercise in animals is known to promote cell survival and functional recovery after brain injuries. However, the detailed pathologic and functional alterations by exercise following an indirect cerebellar injury induced by a TBI are largely unknown. We determined the effects of treadmill exercise on survival of Purkinje neurons and on a population of reactive astrocytes in the gyrus of lobules VIII and IX of the cerebellum after TBI. The rats were divided into four groups: the sham-operation group, the sham-operation with exercise group, the TBI-induction group, and the TBI-induction with exercise group. Cell biological changes of Purkinje neurons following indirect cerebellar injury were analyzed by immunohistochemistry. TBI-induced loss of calbindin-stained Purkinje neurons in the posterior region of the cerebellum and TBI also increased formation of reactive astroyctes in both the granular and molecular layers of the cerebellar posterior region. Treadmill exercise for 10 days after TBI increased the number of calbindin-stained Purkinje neurons and suppressed formation of reactive astroyctes. The present study provides the possibility that treadmill exercise may be an important mediator to enhance survival of Purkinje neurons in TBI-induced indirect cerebellar injury.

Growth-promoting activity of Hominis Placenta extract on regenerating sciatic nerve

AbstractAim:Extract of Hominis Placenta (HP) has been used in oriental medicine as an agent for improving physiological function. The present study was conducted to investigate whether HP treatment in an experimental sciatic nerve injury animal model produces growth-promoting effects on regenerating peripheral nerve fibers after injury.Methods:After HP was injected into a sciatic nerve injury site, changes in protein levels were analyzed in the regenerating nerve area by Western blotting and immunofluorescence staining analyses. For quantitative assessment of axonal regeneration, a retrograde tracing technique was used to identify the neuronal cell bodies corresponding to regenerating axons, and the extent of neurite outgrowth in cultured dorsal root ganglia (DRG) sensory neurons prepared from animals that had experienced a sciatic nerve crush injury 7 d before neuron collection was analyzed.Results:Induction levels of axonal growth-associated protein (GAP-43) in the injured sciatic nerves were elevated by HP treatment. HP treatment also upregulated cell division cycle 2 (Cdc2) protein levels in the distal stump of the injured sciatic nerve. Induced Cdc2 protein was detected in Schwann cells, suggesting that Cdc2 kinase activity maybe involved in the growth-promoting activity of regenerating axons via Schwann cell proliferation. Cell body measurement by retrograde tracing indicated that HP treatment produced significant increases in regenerating motor axons. Finally, HP treatment of cultured DRG sensory neurons significantly increased neurite arborization and elongation.Conclusion:HP promotes the regeneration of injured sciatic axons by upregulating the synthesis of regeneration-related protein factors such as GAP-43 and Cdc2.

Effects of Resistance Training on Skeletal Muscle GLUT-4 Protein and LDH Isozyme Expression in Rats

The purpose of the present study was to investigate the effect of climbing resistance training on GLUT-4 protein and LDH isozyme activities of the soleus and gastrocnemius muscles in rats. Each experimental group was randomly divided into a control group (n

Effects of Relative Swimming Exercise Intensity on mRNA Expression of UCP-1, UCP-3 Brown Adipose Tissue and Blood Insulin, and Glucose in Rat

The purpose of this study was to investigate the UCP-1, UCP-3 mRNA expression in brown adipose tissue with glycometabolism according to intensity and duration of swimming in rat. F344 rat were randomly divided into three groups (n

The Effects of Treadmill Exercise on Inhibition of Soleus Muscle Atrophy and Improvement Functional Recovery after Spinal Cord Contusion in the Rats

Physical activity and exercise can promote sensorimotor recovery from central nerve injury. It has been suggested that the functional recovery promoted by exercise training after spinal cord injury might be associated with insulin-like growth factor-I in the inflicted muscle. To investigate morphological and biochemical change of the soleus muscle after spinal cord injury, all tissues were used for HE 7week in age) were assigned equally to three different groups; Normal (n

Effects of maternal exercise on expression of GLUT-4, VAMP-2 in skeletal muscle and plasma insulin and leptin levels in pregnant rats

The main objective of this study was to investigate the effects of exercise on serum insulin and leptin levels and GLUT-4 and VAMP-2 in skeletal muscles from the pregnant rats. F344 rats were randomly divided into four groups (n