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1.
Zool Res ; 45(2): 233-241, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38287904

RESUMO

Neural tube defects (NTDs) are severe congenital neurodevelopmental disorders arising from incomplete neural tube closure. Although folate supplementation has been shown to mitigate the incidence of NTDs, some cases, often attributable to genetic factors, remain unpreventable. The SHROOM3 gene has been implicated in NTD cases that are unresponsive to folate supplementation; at present, however, the underlying mechanism remains unclear. Neural tube morphogenesis is a complex process involving the folding of the planar epithelium of the neural plate. To determine the role of SHROOM3 in early developmental morphogenesis, we established a neuroepithelial organoid culture system derived from cynomolgus monkeys to closely mimic the in vivo neural plate phase. Loss of SHROOM3 resulted in shorter neuroepithelial cells and smaller nuclei. These morphological changes were attributed to the insufficient recruitment of cytoskeletal proteins, namely fibrous actin (F-actin), myosin II, and phospho-myosin light chain (PMLC), to the apical side of the neuroepithelial cells. Notably, these defects were not rescued by folate supplementation. RNA sequencing revealed that differentially expressed genes were enriched in biological processes associated with cellular and organ morphogenesis. In summary, we established an authentic in vitro system to study NTDs and identified a novel mechanism for NTDs that are unresponsive to folate supplementation.


Assuntos
Proteínas do Citoesqueleto , Defeitos do Tubo Neural , Animais , Proteínas do Citoesqueleto/metabolismo , Tubo Neural/metabolismo , Macaca fascicularis , Defeitos do Tubo Neural/genética , Defeitos do Tubo Neural/metabolismo , Defeitos do Tubo Neural/veterinária , Células Neuroepiteliais/metabolismo , Ácido Fólico/metabolismo , Organoides , Citoesqueleto
2.
Mol Biol Evol ; 40(8)2023 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-37494289

RESUMO

Although the continual expansion of the brain during primate evolution accounts for our enhanced cognitive capabilities, the drivers of brain evolution have scarcely been explored in these ancestral nodes. Here, we performed large-scale comparative genomic, transcriptomic, and epigenomic analyses to investigate the evolutionary alterations acquired by brain genes and provide comprehensive listings of innovatory genetic elements along the evolutionary path from ancestral primates to human. The regulatory sequences associated with brain-expressed genes experienced rapid change, particularly in the ancestor of the Simiiformes. Extensive comparisons of single-cell and bulk transcriptomic data between primate and nonprimate brains revealed that these regulatory sequences may drive the high expression of certain genes in primate brains. Employing in utero electroporation into mouse embryonic cortex, we show that the primate-specific brain-biased gene BMP7 was recruited, probably in the ancestor of the Simiiformes, to regulate neuronal proliferation in the primate ventricular zone. Our study provides a comprehensive listing of genes and regulatory changes along the brain evolution lineage of ancestral primates leading to human. These data should be invaluable for future functional studies that will deepen our understanding not only of the genetic basis of human brain evolution but also of inherited disease.


Assuntos
Encéfalo , Primatas , Camundongos , Humanos , Animais , Primatas/genética , Encéfalo/metabolismo , Evolução Molecular
3.
World J Clin Cases ; 11(7): 1498-1505, 2023 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-36926405

RESUMO

BACKGROUND: Liver metastasis is the most common form of distant metastasis in colorectal cancer, and the only possible curative treatment for patients with colorectal liver metastases (CRLM) is hepatectomy. However, approximately 25% of patients with CRLM have indications for liver resection at the initial diagnosis. Strategies aimed at downstaging large or multifocal tumors to enable curative resection are appealing. CASE SUMMARY: A 42-year-old man was diagnosed with ascending colon cancer and liver metastases. Due to the huge lesion size and compression of the right portal vein, the liver metastases were initially diagnosed as unresectable lesions. The patient was treated with preoperative transcatheter arterial chemoembolization (TACE) consisting of 5-fluorouracil/Leucovorin/oxaliplatin/Endostar®. After four courses, radical right-sided colectomy and ileum transverse colon anastomosis were performed. Postoperatively, the pathological analysis revealed moderately differentiated adenocarcinoma with necrosis and negative margins. Thereafter, S7/S8 partial hepatectomy was performed after two courses of neoadjuvant chemotherapy. Pathological examination of the resected specimen revealed a pathologically complete response (pCR). Intrahepatic recurrence was detected more than two months after the operation, and the patient was then treated with TACE consisting of irinotecan/Leucovorin/fluorouracil therapy plus Endostar®. Subsequently, the patient was treated with a γ-knife to enhance local control. Notably, a pCR was reached, and the patient's overall survival time was > 9 years. CONCLUSION: Multidisciplinary treatment can promote the conversion of initially unresectable colorectal liver metastasis and facilitate complete pathological remission of liver lesions.

4.
Genome Biol ; 21(1): 46, 2020 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-32093779

RESUMO

Following publication of the original paper [1], the authors reported an error in the affiliation of Xin-Tian Hu, who is also affiliated with "Kunming Primate Research Center, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan, China".

5.
Genome Biol ; 20(1): 258, 2019 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-31779658

RESUMO

BACKGROUND: Brain aging is a complex process that depends on the precise regulation of multiple brain regions; however, the underlying molecular mechanisms behind this process remain to be clarified in non-human primates. RESULTS: Here, we explore non-human primate brain aging using 547 transcriptomes originating from 44 brain areas in rhesus macaques (Macaca mulatta). We show that expression connectivity between pairs of cerebral cortex areas as well as expression symmetry between the left and right hemispheres both decrease after aging. Although the aging mechanisms across different brain areas are largely convergent, changes in gene expression and alternative splicing vary at diverse genes, reinforcing the complex multifactorial basis of aging. Through gene co-expression network analysis, we identify nine modules that exhibit gain of connectivity in the aged brain and uncovered a hub gene, PGLS, underlying brain aging. We further confirm the functional significance of PGLS in mice at the gene transcription, molecular, and behavioral levels. CONCLUSIONS: Taken together, our study provides comprehensive transcriptomes on multiple brain regions in non-human primates and provides novel insights into the molecular mechanism of healthy brain aging.


Assuntos
Envelhecimento/metabolismo , Encéfalo/metabolismo , Hidrolases de Éster Carboxílico/genética , Macaca mulatta/metabolismo , Transcriptoma , Envelhecimento/genética , Animais , Macaca mulatta/genética , Masculino , Camundongos
7.
Sci Bull (Beijing) ; 62(12): 820-830, 2017 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-36659315

RESUMO

RNA editing was first discovered in mitochondrial RNA molecular. However, whether adenosine-to-inosine (A-to-I) RNA editing has functions in nuclear genes involved in mitochondria remains elusive. Here, we retrieved 707,246 A-to-I RNA editing sites in Macaca mulatta leveraging massive transcriptomes of 30 different tissues and genomes of nine tissues, together with the reported data, and found that A-to-I RNA editing occurred frequently in nuclear genes that have functions in mitochondria. The mitochondrial structure, the level of ATP production, and the expression of some key genes involved in mitochondrial function were dysregulated after knocking down the expression of ADAR1 and ADAR2, the key genes encoding the enzyme responsible for RNA editing. When investigating dynamic changes of RNA editing during brain development, an amino-acid-changing RNA editing site (I234/V) in MFN1, a mediator of mitochondrial fusion, was identified to be significantly correlated with age, and could influence the function of MFN1. When studying transcriptomes of brain disorder, we found that dysregulated RNA editing sites in autism were also enriched within genes having mitochondrial functions. These data indicated that RNA editing had a significant function in mitochondria via their influence on nuclear genes.

8.
Neural Regen Res ; 11(9): 1464-1470, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27857751

RESUMO

Rhesus monkey neural stem cells are capable of differentiating into neurons and glial cells. Therefore, neural stem cell transplantation can be used to promote functional recovery of the nervous system. Rhesus monkey neural stem cells (1 × 105 cells/µL) were injected into bilateral hippocampi of rats with hippocampal lesions. Confocal laser scanning microscopy demonstrated that green fluorescent protein-labeled transplanted cells survived and grew well. Transplanted cells were detected at the lesion site, but also in the nerve fiber-rich region of the cerebral cortex and corpus callosum. Some transplanted cells differentiated into neurons and glial cells clustering along the ventricular wall, and integrated into the recipient brain. Behavioral tests revealed that spatial learning and memory ability improved, indicating that rhesus monkey neural stem cells noticeably improve spatial learning and memory abilities in rats with hippocampal lesions.

9.
Cell Rep ; 16(4): 1016-1025, 2016 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-27425612

RESUMO

Here, we examine whether neurons differentiated from transplanted stem cells can integrate into the host neural network and function in awake animals, a goal of transplanted stem cell therapy in the brain. We have developed a technique in which a small "hole" is created in the inferior colliculus (IC) of rhesus monkeys, then stem cells are transplanted in situ to allow for investigation of their integration into the auditory neural network. We found that some transplanted cells differentiated into mature neurons and formed synaptic input/output connections with the host neurons. In addition, c-Fos expression increased significantly in the cells after acoustic stimulation, and multichannel recordings indicated IC specific tuning activities in response to auditory stimulation. These results suggest that the transplanted cells have the potential to functionally integrate into the host neural network.


Assuntos
Encéfalo/fisiologia , Diferenciação Celular/fisiologia , Neurônios/fisiologia , Células-Tronco/fisiologia , Vigília/fisiologia , Estimulação Acústica/métodos , Potenciais de Ação/fisiologia , Animais , Células Cultivadas , Colículos Inferiores/fisiologia , Macaca mulatta , Rede Nervosa/fisiologia , Neurogênese/fisiologia , Transplante de Células-Tronco/métodos
10.
Dongwuxue Yanjiu ; 33(2): 225-30, 2012 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-22467400

RESUMO

Glaucoma is a typical irreversible blind neurodegenerative disease for which there is no effective treatment for halting visual deterioration. The recent development of neural stem cells studies sheds light on a potential resolution for this disease. As a result, an appropriate glaucoma modeling method for stem cell transplantation study is needed. In the present study, Dexamethasone was injected unilaterally into the conjunctiva of New Zealand rabbit at the dose of 2.5 mg (5 mg/mL), three times a week. After eight weeks, the eye ground photography showed that the optic nerve head of the treated eye was expanded, and the blood vessel was geniculate compared to the control eye, while the ocular media remained transparent. The hematoxylin-eosin (HE) stain of the retinal nerve fiber layer (RNFL) sections showed optic neuron death in the treated eye. The Heidelberg Retina Tomography (HRT) results showed optic disk morphological changes consistent with the pathophysiology of glaucoma in the treated eye, including a decrease in the rim area (1.10±0.88) mm(2) and mean RNFL thickness (0.44±0.31) mm, and an increase in the cup/disk ratio 0.17±0.13. Then neural stem cells were injected into the vitreous body of the treated eye. After five months, surviving transplanted cells were observed. These results suggest a simple and reproducible chronic glaucoma model, which is appropriate for neural stem cell transplant research, has been successfully developed.


Assuntos
Glaucoma/terapia , Transplante de Células-Tronco/métodos , Animais , Modelos Animais de Doenças , Glaucoma/patologia , Masculino , Coelhos
11.
Dongwuxue Yanjiu ; 33(1): 43-8, 2012 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-22345007

RESUMO

To investigate the characteristics of rhesus monkey embryonic stem cells and to promote their clinical application, the differentiation and proliferation of rosettes neural stem cells from GFP marked rhesus monkey embryonic stem cells were studied The results showed that: 1) A stable and high-efficient neural differentiation system was established. More than 95% of the embryonic stem cells were differentiated into neural stem cells on the 12(th) days of differentiation; 2) the rosettes neural stem cells differentiated from the rhesus monkey embryonic stem cells could maintain their rosettes-shape by proliferating with bFGF/EGF; 3) the neural stem cells could differentiate into neurons after transplanted into the rhesus monkey brain. In conclusion, the rosettes neural stem cells differentiated from rhesus monkey embryonic stem cells could maintain their characteristics after proliferation with bFGF/EGF and they could survive and differentiate into neurons after transplanted into the rhesus monkey brain, which strongly supports the clinical application of neural stem cells in the future.


Assuntos
Diferenciação Celular , Proliferação de Células , Modelos Animais de Doenças , Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/transplante , Macaca mulatta , Doenças do Sistema Nervoso/terapia , Animais , Células Cultivadas , Humanos , Macaca mulatta/fisiologia , Sistema Nervoso/citologia , Doenças do Sistema Nervoso/cirurgia , Neurônios/citologia , Transplante Homólogo
12.
Dongwuxue Yanjiu ; 32(4): 421-7, 2011 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-21842538

RESUMO

To perform electrophysiological recording and other investigations on transplanted neural cells in vivo, we used mechanical damage to establish a special traumatic brain injury model that could distinguish transplanted cells from host cells. The morphology of the trauma-induced holes in the cortex of the rat brain was regular. The model was stable and repeatable. Neural stem cells were transplanted into the trauma-induced hole, and were able to survive for a long time. Most of the transplanted cells differentiated into neurons, and only a small amount turned into glia cells. There was a clear boundary between the host cells and the transplanted cells. Single cell electrophysiological recording on transplanted neural cells were detected in vivo. This study established a stable and repeatable traumatic brain injury model, which could be used to conduct in vivo electrophysiological recording research on transplanted neural cells.


Assuntos
Lesões Encefálicas/terapia , Neurônios/transplante , Animais , Lesões Encefálicas/fisiopatologia , Células Cultivadas , Modelos Animais de Doenças , Fenômenos Eletrofisiológicos , Feminino , Humanos , Masculino , Neurônios/química , Neurônios/fisiologia , Ratos , Ratos Sprague-Dawley , Transplante de Células-Tronco , Células-Tronco/química , Células-Tronco/fisiologia , Transplantes
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