Background Comeal neovascular leakage can lead to edema and secondary scarring. Previous studies have shown that pericytes play a key role in maturation of angiogenesis. The present studies investigate the relationshi...Background Comeal neovascular leakage can lead to edema and secondary scarring. Previous studies have shown that pericytes play a key role in maturation of angiogenesis. The present studies investigate the relationship between vascular permeability and pericyte coverage of endothelial cells in rat corneal neovascular induced by alkali bums. Methods Corneal neovascular vessels induced by alkali bums was performed in Sprague-Dawley rats. Corneas were excised on 1,2, 3, 5, 7 and 10 days after cauterization. The vascular permeability rate was measured by the Evans blue method. The microvessel pericyte coverage index （MPI） was applied to quantify the pericyte coverage through double immunofluorescent staining of frozen sections of corneas with CD31 as the endothelial and α-smooth muscle actin （α-SMA） as the pericyte markers. The correlation between permeability rate and MPI was analyzed. Pericyte coverage was confirmed ultrastructually using transmission electron microscopy. Results The vascular permeability rate was （1.14±0.17）, （0.24±0.08）, （0.29±0.16）, （0.14±0.10）, （0.09±0.06） and （0.05±0.04）μg· ml^-1 · mm^-2respectively on 1, 2, 3, 5, 7 and 10 days after cauterization. The MPI was 0, 16.07%, 11.95%, 43.84%, 73.97% and 86.21% respectively at the above mentioned time points. The correlation coefficient between MPI and the permeability rate was -0.943 （P=-0.005）. Conclusions Pericyte recruitment was significantly correlated with the permeability of comeal neovascularization induced by alkali bums in rats. Therapeutic strategies aiming at anti-leakage should be most effective if they promote pericytes proliferation in the course of corneal neovascularization.展开更多
Background The treatment of spinal cord injury is still a challenge. This study aimed at evaluating the therapeutical effectiveness of neurons derived form mesenchymal stem cells （MSCs） for spinal cord injury. Metho...Background The treatment of spinal cord injury is still a challenge. This study aimed at evaluating the therapeutical effectiveness of neurons derived form mesenchymal stem cells （MSCs） for spinal cord injury. Methods In this study, rhesus MSCs were isolated and induced by cryptotanshinone in vitro and then a process of RT-PCR was used to detect the expression of glutamic acid decarboxylase （GAD） gene. The induced MSCs were tagged with Hoechst 33342 and injected into the injury site of rhesus spinal cord made by the modified Allen method. Following that, behavior analysis was made after 1 week, 1 month, 2 months and 3 months. After 3 months, true blue chloride retrograde tracing study was also used to evaluate the reestablishment of axons pathway and the hematoxylin-eosin （HE） staining and immunohistochemistry were performed after the animals had been killed. Results In this study, the expression of mRNA of GAD gene could be found in the induced MSCs but not in primitive MSCs and immunohistochemistry could also confirm that rhesus MSCs could be induced and differentiated into neurons. Behavior analysis showed that the experimental animals restored the function of spinal cord up to grade 2 -3 of Tarlov classification. Retrograde tracing study showed that true blue chollide could be found in the rostral thoracic spinal cords, red nucleus and sensory-motor cortex. Conclusions These results suggest that the transplantation is safe and effective.展开更多
Background Menin is a ubiquitously expressed protein encoded by the multiple endocrine neoplasia type 1 （MEN1）gene. Besides its importance in endocrine organs, menin has been shown to interact with the mixed lineage...Background Menin is a ubiquitously expressed protein encoded by the multiple endocrine neoplasia type 1 （MEN1）gene. Besides its importance in endocrine organs, menin has been shown to interact with the mixed lineage leukemia （MLL） protein, a histone H3 lysine 4 methyltransferase, and plays a critical role in hematopoiesis and leukemogenesis.Previous studies have shown that menin promotes transforming growth factor beta （TGF-β） signaling in endocrine cells.However, little is known regarding the impact of TGF-β pathway on menin in hematopoietic system. Here, with leukemia cell lines generated from conditional MEN1 or TGF-p receptor （TβRII） knockout mouse models, we investigated the possible cross-talk of these two pathways in leukemia cells.Methods MEN1 or TβRII conditional knockout mice were bred and the bone marrow cells were transduced with retroviruses expressing oncogeneic MLL-AF9 （a mixed lineage leukemia fusion protein） to generate two leukemia cell lines. Cell proliferation assays were performed to investigate the effect of TGF-β treatment on MLL-AF9 transformed leukemia cells with/without MEN1 or TβRII excision. Menin protein was detected with Western blotting and mRNA levels of cell proliferation-related genes Cyclin A2 and Cyclin E2 were examined with real-time RT-PCR for each treated sample.In vivo effect of TGF-p signal on menin expression was also investigated in mouse liver tissue after TβRII excision.Results TGF-β not only inhibited the proliferation of wild type MLL-AF9 transformed mouse bone marrow cells, but also up-regulated menin expression in these cells. Moreover, TGF-P failed to further inhibit the proliferation of Men1-null cells as compared to Men1-expressing control cells. Furthermore, excision of TβRII, a vital component in TGF-β signaling pathway, down-regulated menin expression in MLL-AF9 transformed mouse bone marrow cells. In vivo data also confirmed that menin expression was decreased in liver samples of conditional TβRII knockout mice after TβRII excision.Conclusion These results provided the first piece of evidence of cross-talk between menin and TGF-β signaling pathways in regulating proliferation of leukemia cells, suggesting that manipulating the cross-talk of the two pathways may lead to a novel therapy for leukemia.展开更多
基金We thank for the funding support from the Research and Innovation Project of Graduate Students in Hunan Province(No.CX20190538)the First-class Open Fund for Integrated Chinese and Western Medicine(No.2018ZXYJH05)+1 种基金the Traditional Chinese Medicine First-Class Discipline Open Fund(No.2018ZYX57)the Construction Project of Hunan Engineering Technology Research Center for the Prevention and Treatment of Otorhinolaryngologic Diseases and Protection of Visual Function with Chinese Medicine(No.2018YGC02).
基金National Science Fund for Distinguished Young Scholars(No.30225044)Fund for Innovative Research Groups of China (No. 30321004)Natural Science Foundation of Guangdong Province of China (No. 36652).
文摘Background Comeal neovascular leakage can lead to edema and secondary scarring. Previous studies have shown that pericytes play a key role in maturation of angiogenesis. The present studies investigate the relationship between vascular permeability and pericyte coverage of endothelial cells in rat corneal neovascular induced by alkali bums. Methods Corneal neovascular vessels induced by alkali bums was performed in Sprague-Dawley rats. Corneas were excised on 1,2, 3, 5, 7 and 10 days after cauterization. The vascular permeability rate was measured by the Evans blue method. The microvessel pericyte coverage index （MPI） was applied to quantify the pericyte coverage through double immunofluorescent staining of frozen sections of corneas with CD31 as the endothelial and α-smooth muscle actin （α-SMA） as the pericyte markers. The correlation between permeability rate and MPI was analyzed. Pericyte coverage was confirmed ultrastructually using transmission electron microscopy. Results The vascular permeability rate was （1.14±0.17）, （0.24±0.08）, （0.29±0.16）, （0.14±0.10）, （0.09±0.06） and （0.05±0.04）μg· ml^-1 · mm^-2respectively on 1, 2, 3, 5, 7 and 10 days after cauterization. The MPI was 0, 16.07%, 11.95%, 43.84%, 73.97% and 86.21% respectively at the above mentioned time points. The correlation coefficient between MPI and the permeability rate was -0.943 （P=-0.005）. Conclusions Pericyte recruitment was significantly correlated with the permeability of comeal neovascularization induced by alkali bums in rats. Therapeutic strategies aiming at anti-leakage should be most effective if they promote pericytes proliferation in the course of corneal neovascularization.
文摘Background The treatment of spinal cord injury is still a challenge. This study aimed at evaluating the therapeutical effectiveness of neurons derived form mesenchymal stem cells （MSCs） for spinal cord injury. Methods In this study, rhesus MSCs were isolated and induced by cryptotanshinone in vitro and then a process of RT-PCR was used to detect the expression of glutamic acid decarboxylase （GAD） gene. The induced MSCs were tagged with Hoechst 33342 and injected into the injury site of rhesus spinal cord made by the modified Allen method. Following that, behavior analysis was made after 1 week, 1 month, 2 months and 3 months. After 3 months, true blue chloride retrograde tracing study was also used to evaluate the reestablishment of axons pathway and the hematoxylin-eosin （HE） staining and immunohistochemistry were performed after the animals had been killed. Results In this study, the expression of mRNA of GAD gene could be found in the induced MSCs but not in primitive MSCs and immunohistochemistry could also confirm that rhesus MSCs could be induced and differentiated into neurons. Behavior analysis showed that the experimental animals restored the function of spinal cord up to grade 2 -3 of Tarlov classification. Retrograde tracing study showed that true blue chollide could be found in the rostral thoracic spinal cords, red nucleus and sensory-motor cortex. Conclusions These results suggest that the transplantation is safe and effective.
基金This work was supported by grants from the National Institutes of Health in USA （R01-CA-100912 and R01-CA-113962）, a Fellowship from China Scholarship Council and National Natural Science Foundation of China （No. 30600697）.Acknowledgement： We thank Dr. Harold Moses at Vanderbilt University for providing the mice with the floxed TβRII alleles.
文摘Background Menin is a ubiquitously expressed protein encoded by the multiple endocrine neoplasia type 1 （MEN1）gene. Besides its importance in endocrine organs, menin has been shown to interact with the mixed lineage leukemia （MLL） protein, a histone H3 lysine 4 methyltransferase, and plays a critical role in hematopoiesis and leukemogenesis.Previous studies have shown that menin promotes transforming growth factor beta （TGF-β） signaling in endocrine cells.However, little is known regarding the impact of TGF-β pathway on menin in hematopoietic system. Here, with leukemia cell lines generated from conditional MEN1 or TGF-p receptor （TβRII） knockout mouse models, we investigated the possible cross-talk of these two pathways in leukemia cells.Methods MEN1 or TβRII conditional knockout mice were bred and the bone marrow cells were transduced with retroviruses expressing oncogeneic MLL-AF9 （a mixed lineage leukemia fusion protein） to generate two leukemia cell lines. Cell proliferation assays were performed to investigate the effect of TGF-β treatment on MLL-AF9 transformed leukemia cells with/without MEN1 or TβRII excision. Menin protein was detected with Western blotting and mRNA levels of cell proliferation-related genes Cyclin A2 and Cyclin E2 were examined with real-time RT-PCR for each treated sample.In vivo effect of TGF-p signal on menin expression was also investigated in mouse liver tissue after TβRII excision.Results TGF-β not only inhibited the proliferation of wild type MLL-AF9 transformed mouse bone marrow cells, but also up-regulated menin expression in these cells. Moreover, TGF-P failed to further inhibit the proliferation of Men1-null cells as compared to Men1-expressing control cells. Furthermore, excision of TβRII, a vital component in TGF-β signaling pathway, down-regulated menin expression in MLL-AF9 transformed mouse bone marrow cells. In vivo data also confirmed that menin expression was decreased in liver samples of conditional TβRII knockout mice after TβRII excision.Conclusion These results provided the first piece of evidence of cross-talk between menin and TGF-β signaling pathways in regulating proliferation of leukemia cells, suggesting that manipulating the cross-talk of the two pathways may lead to a novel therapy for leukemia.
