Regenerative potential of targeting glycogen synthase kinase-3 signaling in neural tissues

Multiple roles of glycogen synthase kinase-3（GSK-3）in neural tissues：GSK-3 is a serine/threonine kinase that has two isoforms encoded by two different genes,GSK-3αand GSK-3β,in mammals.GSK-3 has several sites of serine and tyrosine phosphorylation.

Targeted tissue engineering:hydrogels with linear capillary channels for axonal regeneration after spinal cord injury

Spinal cord injury（SCI）frequently results in the permanent loss of function below the level of injury due to the failure of axonal regeneration in the adult mammalian central nervous system（CNS）.The limited intrinsic growth capacity of adult neurons,a lack of growth-promoting factors and the multifactorial inhibitory microenvironment around the lesion site contribute to the lack of axonalregeneration. Strategies such as transplantation of cells,

Reducing intrathecal pressure after traumatic spinal cord injury: a potential clinical target to promote tissue survival

Spinal cord injury （SCI） is an unexpected event that is both devastating and debilitating, resulting in not just motor and sensory loss, but also autonomic dysfunction of the bladder, bowel and sexual organs. Currently, there are no treatments available to improve outcome follow- ing SCI, leaving individuals with permanent and lifelong physical disability. Worldwide it is estimated that more than 500,000 people sustain a SCI each year, with average lifetime cost of paraplegia and quadriplegia estimated at $5 million and $9.5 million respectively. We therefore urgently need effective therapies to improve quality of life following SCI, and this requires a greater understanding of how cell and axonal injury develops after the traumatic event.

Protection of tight junction between RPE cells with tissue factor targeting peptide

AIM：To investigate the effect of tissue factor targeting peptide（TF-TP）on retinal pigment epithelium（RPE）cells tight junctions.METHODS：Cell counting kit-8（CCK-8）was used to measure the proliferation of ARPE-19 cells.Expression of tight junction,ZO-1 in ARPE-19 cells was measured by Western blot and immunofluorescent staining.Western blot was also used to detect the expression of tissue factor（TF）.CEC Transmigration Assay was used to measure the migration of ARPE-19 cells.The transport of fluorescent markers [fluorescein isothiocyanate dextrans of 4,10,20（FD4,FD10,FD20） ]and the transepithelial electrical resistance（TEER）were used to measure in ARPE-19 cell RESULTS：CCK-8 assay showed that 5μmol/L TF-TP can inhibit ARPE-19 cells abnormally proliferation stimulated by lipopolysaccharide（LPS;P〈0.05）.LPS increased the transport of fluorescent markers（FD4,FD10,FD20）and decreased TEER levels in ARPE-19 cells,respectively,which were prevented by 5μmol/L TF-TP pretreatment（P〈0.05）. Furthermore,LPS significantly up-regulated the expression of TF and downregulated the expression of ZO-1（P〈0.05）in ARPE-19 cell which was inhibited by the TF-TP（P〈0.05）.In addition,TF-TP inhibited the abnormal migration induced by LPS in ARPE-19 cell（P〈0.05）.CONCLUSION：Our findings suggest that TF-TP suppressed proliferation and migration of ARPE-19 cells induced by LPS,and maintained the RPE tight junctions through inhibition of TF expression and increased expression of ZO-1.

Insulin resistance in diabetes: The promise of using induced pluripotent stem cell technology

Insulin resistance(IR)is associated with several metabolic disorders,including type 2 diabetes(T2D).The development of IR in insulin target tissues involves genetic and acquired factors.Persons at genetic risk for T2D tend to develop IR several years before glucose intolerance.Several rodent models for both IR and T2D are being used to study the disease pathogenesis;however,these models cannot recapitulate all the aspects of this complex disorder as seen in each individual.Human pluripotent stem cells(hPSCs)can overcome the hurdles faced with the classical mouse models for studying IR.Human induced pluripotent stem cells(hiPSCs)can be generated from the somatic cells of the patients without the need to destroy a human embryo.Therefore,patient-specific hiPSCs can generate cells genetically identical to IR individuals,which can help in distinguishing between genetic and acquired defects in insulin sensitivity.Combining the technologies of genome editing and hiPSCs may provide important information about the genetic factors underlying the development of different forms of IR.Further studies are required to fill the gaps in understanding the pathogenesis of IR and diabetes.In this review,we summarize the factors involved in the development of IR in the insulin-target tissues leading to diabetes.Also,we highlight the use of hPSCs to understand the mechanisms underlying the development of IR.

Effect of Huanglian Jiedu Decoction (黄连解毒汤) on Glucose Transporter 4 Expression in Adipose and Skeletal Muscle Tissues of Insulin Resistant Rats

Objective： To investigate the effects of Huanglian Jiedu Decoction （黄连解毒汤, HLJDD） on glucose transporter 4 （GLUT4） protein expressions in insulin-resistant murine target tissues. Methods： The experimental male Wistar rats were established into insulin resistant models by injecting streptozotocin （STZ 30 mg/kg） via caudal vein and feeding them with high fat high caloric diet, and randomly divided into the model group, the aspirin group and the HLJDD group. Besides, a normal group was set up for control. Changes of body weight （BW）, levels of serum fasting blood glucose （FBG）, serum fasting insulin （FINS） and oral glucose tolerance test （OGTT） were routinely determined. The expression of GLUT4 protein in adipose and skeletal muscle tissues before and after insulin stimulation was determined with Western blot. Results： In the HLJDD group after treatment, BW and FBG got decreased, OGTT improved, and the expression and translocation of GLUT4 protein elevated obviously, either before or after insulin stimulation, as compared with those in the model group, showing significant differences respectively. Conclusion： The mechanism of improving insulin resistance by HLJDD is probably associated with its effect in elevating GLUT4 protein expression and translocation in adipose and skeletal muscle tissues of insulin resistant rats.