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1.
Curr Zool ; 70(5): 596-606, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39463695

RESUMO

Small and isolated populations face several intrinsic risks, such as genetic drift, inbreeding depression, and reduced gene flow. Thus, patterns of genetic diversity and differentiation have become an important focus of conservation genetics research. The golden snub-nosed monkey Rhinopithecus roxellana, an endangered species endemic to China, has experienced rapid reduction in population size and severe population fragmentation over the past few decades. We measured the patterns of genetic diversity and population differentiation using both neutral microsatellites and adaptive major histocompatibility complex (MHC) genes in 2 R. roxellana populations (DPY and GNG) distributed on the northern and southern slopes of the Qinling Mountains, respectively. Eight MHC-linked haplotypes formed by 5 DQA1 alleles, 5 DQB1 alleles, 5 DRB1 alleles, and 4 DRB2 alleles were detected in the 2 populations. The larger GNG population showed higher genetic variation for both MHC and microsatellites than the smaller DPY population, suggesting an effect of genetic drift on genetic variation. Genetic differentiation index (F ST) outlier analyses, principal coordinate analysis (PCoA), and inferred population genetic structure showed lower genetic differentiation in the MHC variations than microsatellites, suggesting that pathogen-mediated balancing selection, rather than local adaptation, homogenized the MHC genes of both populations. This study indicates that both balancing selection and genetic drift may shape genetic variation and differentiation in small and fragmented populations.

2.
Neural Regen Res ; 2024 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-39314167

RESUMO

Although microglial polarization and neuroinflammation are crucial cellular responses after traumatic brain injury, the fundamental regulatory and functional mechanisms remain insufficiently understood. As potent anti-inflammatory agents, the use of glucocorticoids in traumatic brain injury is still controversial, and their regulatory effects on microglial polarization are not yet known. In the present study, we sought to determine whether exacerbation of traumatic brain injury caused by high-dose dexamethasone is related to its regulatory effects on microglial polarization and its mechanisms of action. In vitro cultured BV2 cells and primary microglia and a controlled cortical impact mouse model were used to investigate the effects of dexamethasone on microglial polarization. Lipopolysaccharide, dexamethasone, RU486 (a glucocorticoid receptor antagonist), and ruxolitinib (a Janus kinase 1 antagonist) were administered. RNA-sequencing data obtained from a C57BL/6 mouse model of traumatic brain injury were used to identify potential targets of dexamethasone. The Morris water maze, quantitative reverse transcription-polymerase chain reaction, western blotting, immunofluorescence and confocal microscopy analysis, and TUNEL, Nissl, and Golgi staining were performed to investigate our hypothesis. High-throughput sequencing results showed that arginase 1, a marker of M2 microglia, was significantly downregulated in the dexamethasone group compared with the traumatic brain injury group at 3 days post-traumatic brain injury. Thus dexamethasone inhibited M1 and M2 microglia, with a more pronounced inhibitory effect on M2 microglia in vitro and in vivo. Glucocorticoid receptor plays an indispensable role in microglial polarization after dexamethasone treatment following traumatic brain injury. Additionally, glucocorticoid receptor activation increased the number of apoptotic cells and neuronal death, and also decreased the density of dendritic spines. A possible downstream receptor signaling mechanism is the GR/JAK1/STAT3 pathway. Overactivation of glucocorticoid receptor by high-dose dexamethasone reduced the expression of M2 microglia, which plays an anti-inflammatory role. In contrast, inhibiting the activation of glucocorticoid receptor reduced the number of apoptotic glia and neurons and decreased the loss of dendritic spines after traumatic brain injury. Dexamethasone may exert its neurotoxic effects by inhibiting M2 microglia through the GR/JAK1/STAT3 signaling pathway.

4.
Biomed Pharmacother ; 173: 116419, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38479178

RESUMO

BACKGROUND: Repetitive mild traumatic brain injury (rmTBI) can lead to somatic, emotional, and cognitive symptoms that persist for years after the initial injury. Although the ability of various treatments to promote recovery after rmTBI has been explored, the optimal time window for early intervention after rmTBI is unclear. Previous research has shown that hydrogen-rich water (HRW) can diffuse through the blood-brain - barrier, attenuate local oxidative stress, and reduce neuronal apoptosis in patients with severe traumatic brain injury. However, research on the effect of HRW on rmTBI is scarce. AIMS: The objectives of this study were to explore the following changes after rmTBI and HRW treatment: (i) temporal changes in inflammasome activation and oxidative stress-related protein expression through immunoblotting, (ii) temporal changes in neuron/myelin-related metabolite concentrations in vivo through magnetic resonance spectroscopy, (iii) myelin structural changes in late-stage rmTBI via immunofluorescence, and (iv) postinjury anxiety/depression-like behaviors and spatial learning and memory impairment. RESULTS: NLRP-3 expression in the rmTBI group was elevated at 7 and 14 DPI, and inflammasome marker levels returned to normal at 30 DPI. Oxidative stress persisted throughout the first month postinjury. HRW replacement significantly decreased Nrf2 expression in the prefrontal cortex and hippocampal CA2 region at 14 and 30 DPI, respectively. Edema and local gliosis in the hippocampus and restricted diffusion in the thalamus were observed on MR-ADC images. The tCho/tCr ratio in the rmTBI group was elevated, and the tNAA/tCr ratio was decreased at 30 DPI. Compared with the mice in the other groups, the mice in the rmTBI group spent more time exploring the open arms in the elevated plus maze (P < 0.05) and were more active in the maze (longer total distance traveled). In the sucrose preference test, the rmTBI group exhibited anhedonia. In the Morris water maze test, the latency to find the hidden platform in the rmTBI group was longer than that in the sham and HRW groups (P < 0.05). CONCLUSION: Early intervention with HRW can attenuate inflammasome assembly and reduce oxidative stress after rmTBI. These changes may restore local oligodendrocyte function, promote myelin repair, prevent axonal damage and neuronal apoptosis, and alleviate depression-like behavior and cognitive impairment.


Assuntos
Concussão Encefálica , Disfunção Cognitiva , Camundongos , Humanos , Animais , Bainha de Mielina/metabolismo , Depressão , Inflamassomos/metabolismo , Aprendizagem em Labirinto , Estresse Oxidativo , Disfunção Cognitiva/metabolismo , Inflamação/metabolismo , Receptores de Antígenos de Linfócitos T , Modelos Animais de Doenças
5.
CNS Neurosci Ther ; 29(10): 2873-2883, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37081759

RESUMO

AIMS: To investigate astrocyte-related phagocytosis of synapses in the ipsilateral hippocampus after traumatic brain injury (TBI). METHODS: We performed controlled cortical impact to simulate TBI in mice. Seven days postinjury, we performed cognitive tests, synapse quantification, and examination of astrocytic phagocytosis in association with Megf10 expression. RESULTS: During the subacute stage post-TBI, we found a reduction in excitatory postsynaptic materials in the ipsilateral hippocampus, which was consistent with poor performance in the cognitive test. The transcriptome data suggested that robust phagocytosis was responsible for this process. Coincidently, we identified phagocytic astrocytes containing secondary lysosomes that were wrapped around the synapses in the ipsilateral hippocampus. Moreover, a significant increase in the co-location of GFAP and PSD-95 in the CA1 region suggested astrocytic engulfment of excitatory postsynaptic proteins. After examining the reported phagocytic pathways, we found that both the transcription level and protein expression of Megf10 were elevated. Co-immunofluorescence of GFAP and Megf10 demonstrated that the expression of Megf10 was spatially upregulated in astrocytes, exclusively in the CA1 region, and was related to the astrocytic engulfment of PSD-95. CONCLUSION: Our study elaborated that the Megf10-related astrocytic engulfment of PSD-95 in the CA1 region of the ipsilateral hippocampus aggravated cognitive dysfunction following severe TBI.


Assuntos
Astrócitos , Lesões Encefálicas Traumáticas , Camundongos , Animais , Astrócitos/metabolismo , Hipocampo/metabolismo , Lesões Encefálicas Traumáticas/metabolismo , Proteína 4 Homóloga a Disks-Large/metabolismo , Sinapses/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo
6.
Altern Ther Health Med ; 29(5): 255-261, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37083646

RESUMO

Objective: To explore the effect of the deletion of the icl1 gene and icl2 gene on the growth rate of Mycobacterium tuberculosis (Mtb) and the specific regulatory mechanism involved. Methods: H37Rv was purchased from the Tuberculosis Prevention and Control Institute, and H37Rv was grown in Middlebrook 7H9 broth. Macrophages THP-1 cells were purchased by our researchers from the Cell Bank of the Chinese Academy of Sciences, which were maintained in Roswell Park Memorial Institute (RPMI) 1640 medium supplemented with 10% fetal bovine serum (FBS), at 37°C and 5% CO2. The experiment was divided into 3 groups: the control group (H37Rv infected with THP-1 cells), the icl1/2 deletion group (H37Rv infected with icl1/2 deleted THP-1 cells) and the icl1/2 complementation group (H37Rv infected with icl1/2 deletion, icl1/2 complementary THP-1 cells). Absorbance was measured with a microplate spectrophotometer and the bacterial growth rate was calculated. The colony-forming units (CFU) obtained from the dilution was used to calculate the total number of CFU per milliliter and the percentage of survival of mycobacteria. The protein levels of isocitrate lyase 1 (ICL1), ICL2, p-mTOR and p-Akt were analyzed by Western blot. The CD4+ level was analyzed by flow cytometry. The mRNA expression levels of CCL20, CXCL2, CXCL8, interferon gamma (IFN-γ), interleukin (IL)-17 and IL-22 were analyzed using the quantitative reverse transcription polymerase chain reaction (RT-qPCR) method. Stably transformed monomeric red fluorescent protein (mRFP)-green fluorescent protein (GFP)-LC3 reporter THP-1 cells were used to monitor the aggregation of LC3B in autophagosomes and autophagolysosomes. Results: The Mtb growth rate and CFU of the icl1/2 deletion group were decreased in comparison with the control group (P < .05). When compared with the icl1/2 deletion group, however, the Mtb growth rate and CFU of the icl1/2 complementation group were associated with increased results (P < .05). The protein levels of ICL1 and ICL2 in the icl1/2 deletion group were significantly decreased compared with the control group (P < .05), which were evidently increased in the icl1/2 complementation group when compared with the icl1/2 deletion group (P < .05). In addition, compared with the control group (25.16 ± 2.18), the level of CD4+ appeared to be increased in the icl1/2 deletion group (62.37 ± 5.46) (P < .05), while it was decreased in the icl1/2 complementation group compared with the icl1/2 deletion group (28.33 ± 1.32) (P < .05). The expression levels of chemokine (C-C motif) ligand 20 (CCL20), chemokine (C-X-C motif) ligand 2 (CXCL2), chemokine (C-X-C motif) ligand 8 (CXCL8), IL-17, IFN-γ, and IL-22 mRNA were increased in the icl1/2 deletion group compared with the control group (P < .05), which were significantly decreased in the icl1/2 complementary group compared with the icl1/2 deletion group (P < .05). A comparison between the control group and the icl1/2 deletion group showed that the latter increased the formation of autophagosomes and autophagolysosomes in H37Rv-infected cells (P < .05). However, compared with the icl1/2 deletion group, the icl1/2 complementation group decreased the formation of autophagosomes and autolysosomes in H37Rv-infected cells (P < .05). Moreover, the expression levels of phosphor-mammalian target of rapamycin (p-mTOR) and p-Akt in the icl1/2 deletion group were significantly reduced compared with the control group (P < .05), and were increased in the icl1/2 complementation group compared with the icl1/2 deletion group (P < .05). Conclusion: Loss of icl1/2 was believed to increase the expression of CD4 and CCL20, CXCL8 as well as CXCL2 in the immune system, which increased autophagy. Furthermore, it exerted potential in inhibiting the growth of intracellular Mtb in macrophages.


Assuntos
Mycobacterium tuberculosis , Tuberculose , Humanos , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ligantes , Tuberculose/genética , Serina-Treonina Quinases TOR/metabolismo , RNA Mensageiro
7.
Mol Ecol ; 32(12): 3239-3256, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36942819

RESUMO

Genes of the major histocompatibility complex (MHC) play important roles in vertebrate immunocompetence. MHC genes thus offer females indirect benefits to mate choice through the production of offspring of an optimal MHC genotype. Females may choose males with specific MHC haplotypes, dissimilar MHC genotypes, MHC heterozygous males or MHC-diverse males. We tested these four alternatives for both female social and paternal choice in wild golden snub-nosed monkeys (Rhinopithecus roxellana) by examining overall genetic variability (via microsatellites) and four MHC-genes (DRB1, DRB2, DQA1 and DQB1). Monte Carlo randomization tests showed that MHC dissimilarity was favoured for social choice (males to which females were socially affiliated) and intermediate MHC dissimilarity was favoured in paternal choice (fathers of offspring). No evidence of inbreeding avoidance was found for either social or paternal mates. We found that MHC heterozygotes, higher microsatellite multilocus heterozygosity and higher microsatellites diversity were favoured for social mates, and higher microsatellite diversity was favoured for paternal mates. Independent of male age, we found that the formation of male-female social pairings is significantly predicted by compatibility based on the sharing of MHC haplotypes. However, we found no evidence of independent genetic effects on the duration of male-female social pairings, male social status (achieving OMU leader male status or not), the number of females with which individual leader males paired, the likelihood of potential male-female pairings producing offspring, or whether males fathered offspring or not. Overall, our findings suggest different genetic factors are involved in social and paternal choice in R. roxellana.


Assuntos
Colobinae , Presbytini , Animais , Masculino , Feminino , Presbytini/genética , Colobinae/genética , Genótipo , Complexo Principal de Histocompatibilidade/genética
8.
Transl Neurosci ; 14(1): 20220272, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36815939

RESUMO

A deeper understanding of the underlying biological mechanisms of secondary brain injury induced by traumatic brain injury (TBI) will greatly advance the development of effective treatments for patients with TBI. Hypoxia-inducible factor-1 alpha (HIF-1α) is a central regulator of cellular response to hypoxia. In addition, growing evidence shows that HIF-1α plays the important role in TBI-induced changes in biological processes; however, detailed functional mechanisms are not completely known. The aim of the present work was to further explore HIF-1α-mediated events after TBI. To this end, next-generation sequencing, coupled with cellular and molecular analysis, was adopted to interrogate vulnerable events in a rat controlled cortical impact model of TBI. The results demonstrated that TBI induced accumulation of HIF-1α at the peri-injury site at 24 h post-injury, which was associated with neuronal loss. Moreover, gene set enrichment analysis unveiled that neuroinflammation, especially an innate inflammatory response, was significantly evoked by TBI, which could be attenuated by the inhibition of HIF-1α. Furthermore, the inhibition of HIF-1α could mitigate the activation of microglia and astrocytes. Taken together, all these data implied that HIF-1α might contribute to secondary brain injury through regulating neuroinflammation.

9.
Neural Regen Res ; 18(1): 155-161, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35799536

RESUMO

Proteomics is a powerful tool that can be used to elucidate the underlying mechanisms of diseases and identify new biomarkers. Therefore, it may also be helpful for understanding the detailed pathological mechanism of traumatic brain injury (TBI). In this study, we performed Tandem Mass Tag-based quantitative analysis of cortical proteome profiles in a mouse model of TBI. Our results showed that there were 302 differentially expressed proteins in TBI mice compared with normal mice 7 days after injury. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analyses showed that these differentially expressed proteins were predominantly involved in inflammatory responses, including complement and coagulation cascades, as well as chemokine signaling pathways. Subsequent transcription factor analysis revealed that the inflammation-related transcription factors NF-κB1, RelA, IRF1, STAT1, and Spi1 play pivotal roles in the secondary injury that occurs after TBI, which further corroborates the functional enrichment for inflammatory factors. Our results suggest that inflammation-related proteins and inflammatory responses are promising targets for the treatment of TBI.

10.
Neural Regen Res ; 18(5): 1046-1051, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36254991

RESUMO

After brain injury, infiltration and abnormal activation of neutrophils damages brain tissue and worsens inflammation, but the mediators that connect activated neutrophils with neuroinflammation have not yet been fully clarified. To identify regulators of neutrophil-mediated neuroinflammation after traumatic brain injury, a mouse model of traumatic brain injury was established by controlled cortical impact. At 7 days post-injury (sub-acute phase), genome-wide transcriptomic data showed that interleukin 17A-associated signaling pathways were markedly upregulated, suggesting that interleukin 17A may be involved in neuroinflammation. Double immunofluorescence staining showed that interleukin 17A was largely secreted by neutrophils rather than by glial cells and neurons. Furthermore, nuclear factor-kappaB and Stat3, both of which are important effectors in interleukin 17A-mediated proinflammatory responses, were significantly activated. Collectively, our findings suggest that neutrophil-derived interleukin 17A participates in neutrophil-mediated neuroinflammation during the subacute phase of traumatic brain injury. Therefore, interleukin 17A may be a promising therapeutic target for traumatic brain injury.

11.
Hepatol Int ; 16(5): 1220-1233, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35947245

RESUMO

BACKGROUND: Hepatocellular carcinoma (HCC) is an aggressive carcinoma with genome instability. Long non-coding RNAs (LncRNAs) have been functionally associated with genomic instability in cancers. However, the identification and prognostic value of lncRNAs related to genome instability have not been explored in hepatocellular carcinoma. In this study, we aim to identify a genomic instability-related lncRNA signature for predicting prognosis and the efficacy of immunotherapy in HCC patients. METHODS: According to the somatic mutation and transcript data of 364 patients with HCC, we determined differentially expressed genome instability-related lncRNAs (GInLncRNAs). Gene ontology (GO) enrichment analyses and Kyoto Encyclopedia of genes and genomes enrichment analyses revealed the potential functions of genes co-expressed with those lncRNAs involved in cancer development and immune function. We further determined a genome instability-related lncRNA signature (GInLncSig) through Cox regression analysis and LASSO regression analysis. Thereafter, we performed correlation analyses with mutations, clinical stratification analyses, and survival analyses to evaluate GInLncSig predictive function. Subsequently, we construct a nomogram model for prognostic assessments of patients with HCC. Finally, we performed Immunocytes infiltration analysis, gene set enrichment analysis (ssGSEA) of immunity circle-associated pathways, and T cell-inflamed score to explore GInLncSig's potential value in guiding immunotherapy. RESULTS: We identified 11 independent prognosis-associated GInLncRNAs (AC002511.2, LINC00501, LINC02055, LINC02714, LINC01508, LOC105371967, RP11_96A15.1, RP11_305F18.1, RP11_342M1.3, RP11_432J24.3, U95743.1) to construct a GInLncSig. According to the risk score calculated by GInLncSig, the high-risk group was characterized by a higher somatic mutation count, significantly poorer clinical prognosis, higher T cell-inflamed score, and specific tumor immune infiltration status compared to the low-risk group. Furthermore, we constructed a nomogram model to improve the reliability and clinical utility of predicting the prognosis of patients with HCC. CONCLUSION: Our study established a reliable prognostic prediction signature that could be a tool for prognosis prediction and a promising predictive biomarker of immunotherapy in hepatocellular carcinoma.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , RNA Longo não Codificante , Carcinoma Hepatocelular/patologia , Regulação Neoplásica da Expressão Gênica , Instabilidade Genômica , Humanos , Estimativa de Kaplan-Meier , Neoplasias Hepáticas/patologia , Mutação , Prognóstico , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Reprodutibilidade dos Testes , Microambiente Tumoral/genética
12.
Brain Res Bull ; 188: 21-29, 2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-35868500

RESUMO

The brain is highly integrated and thus unilateral injury can impact the contralateral hemisphere. However, further research is needed to clarify the changes in the response of the contralateral homotopic area to ipsilateral injury. We hypothesized that severe unilateral brain injury would be accompanied by contralateral synaptic changes that are related to functional recovery. To test this, we divided rats into sham and experimental groups. In the experimental group, we performed right motor cortex resection. These rats were further divided into three subgroups according to post-injury time: 7 days, 14 days, and 30 days post-injury. Rats in each group were evaluated using a beam walking test to quantify the recovery of motor function, and all rats received an injection of adeno-associated virus-containing green fluorescent protein (GFP). Finally, we conducted morphological and histological analyses to identify synaptic changes. Over time, the behavior of the rats that underwent right motor cortex resection recovered. Furthermore, in contrast to the sham group, the experimental groups exhibited an increase in the spine density and expression of synaptic proteins in layer V of the contralateral motor cortex, which was consistent with the GFP-labeled neurons. Moreover, more immature spines were observed 7 days post-injury. Notably, spine morphology matured from 7 to 30 days, and the increase in Synapsin-1 intensity in layer V peaked 14 days after the resection, whereas PSD-95 intensity continued to increase until day 30. Our findings suggested that following motor function recovery from unilateral brain injury, spine morphology and synaptic proteins change dynamically in the contralateral hemisphere.


Assuntos
Lesões Encefálicas , Córtex Motor , Animais , Encéfalo , Lesões Encefálicas/patologia , Proteína 4 Homóloga a Disks-Large , Ratos , Recuperação de Função Fisiológica/fisiologia
13.
World Neurosurg ; 164: e436-e445, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35533950

RESUMO

BACKGROUND: Pedicular screws (PS) often are used in lumbar fusion. Cortical bone trajectory (CBT) is a novel technology in lumbar fusion with less evidence of clinical outcomes. Therefore, we conducted a meta-analysis to compare the efficacy and safety between CBT screw fixation and traditional PS in lumbar fusion surgery. METHODS: Multiple databases were searched for the articles that compared CBT and traditional PS in lumbar fusion surgeries. Meta-analysis was conducted by RevMan 5.3 software. The following indicators were abstracted: visual analog scale (VAS) scores for back and leg pain, Oswestry Disability Index (ODI), Japanese Orthopaedic Association (JOA) score, surgical duration, complications, and blood loss. The quality of the articles was assessed by the Newcastle-Ottawa Scale or Cochrane Handbook. RESULTS: In total, 25 studies were included, involving a total of 1735 patients. There was no difference in preoperative VAS scores, JOA, ODI, postoperative VAS scores, and fusion rates. In addition, postoperative JOA (mean difference [MD] = 0.78, P = 0.02), ODI (MD = -2.09, P = 0.03), surgical duration (MD = -26.90, P = 0.02), complications (MD = 0.70, P = 0.03), and blood loss (MD = -85.27, P = 0.0009) showed greater improvement trends in the CBT group than the PS group, with significant difference. CONCLUSIONS: CBT reduced the rate of complications, surgical duration, blood loss, postoperative ODI, and JOA scores. The CBT technique, with better postoperative outcomes, achieved similar fusion rates compared with the PS technique.


Assuntos
Parafusos Pediculares , Fusão Vertebral , Osso Cortical/cirurgia , Humanos , Vértebras Lombares/cirurgia , Fusão Vertebral/métodos , Resultado do Tratamento
14.
Cell Death Dis ; 13(2): 131, 2022 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-35136016

RESUMO

Worldwide, nasopharyngeal carcinoma (NPC) is a rare head and neck cancer; however, it is a common malignancy in southern China. Radiotherapy is the most important treatment strategy for NPC. However, although radiotherapy is a strong tool to kill cancer cells, paradoxically it also promotes aggressive phenotypes. Therefore, we mimicked the treatment process in NPC cells in vitro. Upon exposure to radiation, a subpopulation of NPC cells gradually developed resistance to radiation and displayed cancer stem-cell characteristics. Radiation-induced stemness largely depends on the accumulation of the antiapoptotic myeloid cell leukemia 1 (MCL-1) protein. Upregulated MCL-1 levels were caused by increased stability and more importantly, enhanced protein synthesis. We showed that repeated ionizing radiation resulted in persistently enhanced reactive oxygen species (ROS) production at a higher basal level, further promoting protein kinase B (AKT) signaling activation. Intracellular ROS and AKT activation form a positive feedback loop in the process of MCL-1 protein synthesis, which in turn induces stemness and radioresistance. AKT/MCL-1 axis inhibition attenuated radiation-induced resistance, providing a potential target to reverse radiation therapy-induced radioresistance.


Assuntos
Proteína de Sequência 1 de Leucemia de Células Mieloides , Neoplasias Nasofaríngeas , Proteínas Proto-Oncogênicas c-akt , Linhagem Celular Tumoral , Humanos , Proteína de Sequência 1 de Leucemia de Células Mieloides/genética , Carcinoma Nasofaríngeo/genética , Carcinoma Nasofaríngeo/patologia , Carcinoma Nasofaríngeo/radioterapia , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/patologia , Neoplasias Nasofaríngeas/radioterapia , Tolerância a Radiação/genética , Espécies Reativas de Oxigênio
15.
Neural Regen Res ; 17(2): 386-394, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34269214

RESUMO

Transfer RNA (tRNA)-derived small RNAs (tsRNAs) are a recently established family of regulatory small non-coding RNAs that modulate diverse biological processes. Growing evidence indicates that tsRNAs are involved in neurological disorders and play a role in the pathogenesis of neurodegenerative disease. However, whether tsRNAs are involved in traumatic brain injury-induced secondary injury remains poorly understood. In this study, a mouse controlled cortical impact model of traumatic brain injury was established, and integrated tsRNA and messenger RNA (mRNA) transcriptome sequencing were used. The results revealed that 103 tsRNAs were differentially expressed in the mouse model of traumatic brain injury at 72 hours, of which 56 tsRNAs were upregulated and 47 tsRNAs were downregulated. Based on microRNA-like seed matching and Pearson correlation analysis, 57 differentially expressed tsRNA-mRNA interaction pairs were identified, including 29 tsRNAs and 26 mRNAs. Moreover, Gene Ontology annotation of target genes revealed that the significantly enriched terms were primarily associated with inflammation and synaptic function. Collectively, our findings suggest that tsRNAs may be associated with traumatic brain injury-induced secondary brain injury, and are thus a potential therapeutic target for traumatic brain injury. The study was approved by the Beijing Neurosurgical Institute Animal Care and Use Committee (approval No. 20190411) on April 11, 2019.

16.
Plant Direct ; 5(11): e362, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34849452

RESUMO

Huperzia serrata (H. serrata) produces various types of effective lycopodium alkaloids, especially Huperzine A (HupA), which is a promising drug for the treatment of Alzheimer's disease. Numerous studies focused on the chemistry, bioactivities, toxicology, and clinical trials of HupA; however, the public genomic and transcriptomic resources are very limited for H. serrata research, especially for the selection of optimum reference genes. Based on the full-length transcriptome datasets and previous studies, 10 traditional and three new candidate reference genes were selected in different tissue of H. serrata. Then, two optimal reference genes GAPDHB and HisH2A were confirmed by four analysis methods. In order to further verify the accuracy of the two reference genes, they were used to analyze the expression patterns of four HupA-biosynthetic genes (lysine decarboxylas, RS-norcoclaurine 6-O-methyltransferase, cytochrome P45072A1, and copper amine oxidase). The data suggested that the expression pattern of HupA-biosynthetic genes was consistent with them in transcriptome sequencing in different tissue of H. serrata. This study identified that GAPDHB and HisH2A provides the reliable normalization for analyzing the HupA biosynthetic gene expression in different tissues of H. serrata on the transcriptional level.

17.
J Gastrointest Oncol ; 12(4): 1851-1859, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34532133

RESUMO

BACKGROUND: Hepatocellular carcinoma (HCC) is one of the most common malignancies worldwide and its prognosis remains dismal. Hence, it is important to identify the diagnostic and prognostic biomarkers for HCC. Urokinase plasminogen activator (uPA), an extracellular matrix (ECM)-degrading protease, plays a pivotal role in the invasion and metastasis of HCC. METHODS: To confirm the clinical significance of uPA in HCC, we explored uPA expression in HCC in The Cancer Genome Atlas (TCGA) database. The expression level of uPA was further verified by quantitative reverse transcription polymerized chain reaction (qRT-PCR) in 133 pairs of primary HCC samples. A survival analysis was conducted with the Kaplan-Meier method in the HCC samples and TCGA database. RESULTS: Our results showed that uPA was overexpressed in HCC and was significantly associated with HCC tumor size (P=0.015), differentiation grade (P=0.028), and absence of tumor encapsulation (P=0.010). Patients with high uPA expression levels had a poor outcome (P=0.026). TCGA database analysis was also consistent with our experimental results. CONCLUSIONS: In conclusion, our findings revealed that uPA was overexpressed in HCC and was related to HCC malignant features including tumor size, differentiation grade and absence of tumor encapsulation. High uPA expression had a shorter survival time. It is a potential prognostic biomarker of HCC.

18.
Front Mol Biosci ; 8: 706570, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34552959

RESUMO

Objective: Multiple myeloma (MM) represents a common age-associated malignancy globally. The function and underlying mechanism of antisense lncRNA LBX2-AS1 remain ambiguous in multiple myeloma (MM). Herein, we aimed to observe the biological implication of this lncRNA in MM. Methods: RT-qPCR was employed to examine circulating LBX2-AS1 and LBX2 in 60 paired MM and healthy subjects. Correlation between the two was analyzed by Pearson test. Under transfection with shLBX2-AS1, proliferation and apoptosis were evaluated in MM cells through CCK-8, colony formation and flow cytometry. LBX2 expression was examined in MM cells with shLBX2-AS1 or pcDNA3.1-LBX2 transfection. Following treatment with cycloheximide or actinomycin D, LBX2 expression was examined in pcDNA3.1-LBX2-transfected MM cells at different time points. Rescue assays were then presented. Finally, xenograft tumor models were established. Results: Circulating LBX2-AS1 was up-regulated in MM patients and positively correlated to LBX2 expression. Area under the curve (AUC) of LBX2-AS1 expression was 0.7525. Its up-regulation was also found in MM cells and primarily distributed in cytoplasm. LBX2-AS1 knockdown distinctly weakened proliferative ability and induced apoptosis in MM cells. Overexpressing LBX2-AS1 markedly strengthened LBX2 expression by increasing its mRNA stability. Rescue assays showed that silencing LBX2-AS1 distinctly weakened the pcDNA3.1-LBX2-induced increase in proliferation and decrease in apoptosis for MM cells. Silencing LBX2-AS1 markedly weakened tumor growth. Conclusion: Our data demonstrated that circulating LBX2-AS1 could be an underlying diagnostic marker in MM. Targeting LBX2-AS1 suppressed tumor progression by affecting mRNA stability of LBX2 in MM. Hence, LBX2-AS1 could be a novel therapeutic marker against MM.

19.
Front Pharmacol ; 12: 713715, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34381366

RESUMO

In our recent studies, we reported that mineralocorticoid receptor (MR) had the opposite effects of glucocorticoid receptor (GR) on neural cell survival after traumatic brain injury (TBI). However, whether short-term use of high-dose natural glucocorticoids, which are mixed agonists of both MR and GR, leads to neurotoxic effects by inducing excessive GR activation is unclear, as is the threshold GR activation level and the possible signaling pathways remain unclear. In this study, we examined the dual dose-dependent effects of corticosterone (CORT) on spatial memory, hippocampal cell survival and receptor-mediated downstream signaling pathways after TBI. We found that different doses of CORT exhibited dual effects on hippocampal cell survival and rat spatial memory. Low doses of CORT (0.3 and 3 mg/kg) significantly increased MR activation, upregulated Akt/CREB/Bad phosphorylation and Bcl-2 concentration, reduced the number of apoptotic neural cells, and subsequently improved rat spatial memory. In contrast, a high dose of CORT (30 mg/kg) exerted the opposite effects by overactivating GR, upregulating P53/Bax levels, and inhibiting Erk/CREB activity. The results suggest that the neuroprotective and neurotoxic effects of endogenous GC depend on a threshold level and that a higher dose of GC, even for short-term use, should be avoided after TBI.

20.
Am J Transl Res ; 13(3): 1483-1493, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33841672

RESUMO

BACKGROUND: Astaxanthin (ATX) is a carotenoid pigment with effective antioxidant, anti-inflammatory, antitumor and immunomodulatory actions. ATX has been proposed to exert neuroprotective effects and attenuate oxidative stress in mice after traumatic brain injury (TBI). The nuclear factor erythroid 2-related factor 2 (Nrf2)-heme oxygenase 1 (HO-1) signaling pathway is stimulated after TBI and activates a compensatory mechanism against TBI. Nevertheless, the effect of ATX on the pathophysiology of TBI in mice is limited. Our present study evaluated the neuroprotection afforded by ATX and the possible role of the Nrf2/HO-1 pathway in experimental TBI. MATERIALS AND METHODS: Mice were casually separated into 3 groups: the sham, TBI + vehicle, and TBI + ATX (100 mg/kg, intraperitoneally administered) groups. Neurobehaviors of the mice were assessed using the neurological severity scores (NSSs), the forced swimming test (FST) and the rotarod test. Levels of the Nrf2, HO-1, NAD(P)H: quinine oxidoreductase-1 (NQO1), cleaved caspase3 (C-caspase3), and superoxide dismutase1 (SOD1) proteins and levels of the Nrf2 and HO-1 mRNAs were assessed. In addition, Nrf2 nuclear import and apoptosis were measured after TBI. RESULTS: The ATX treatment significantly improved the neurological status, promoted Nrf2 activation, and upregulated the expression of the Nrf2 and HO-1 mRNAs and the levels of the Nrf2, HO-1, and NQO1 proteins after TBI. The level of the SOD1 protein was decreased after TBI and increased after ATX treatment; however, the difference was not significant. ATX markedly reduced the level of the C-caspase3 protein and the number of TUNEL-positive cells, indicating that it exerted an antiapoptotic effect. Immunofluorescence staining confirmed that ATX promoted Nrf2 nuclear import. CONCLUSIONS: Based on our study, ATX possibly affords neuroprotection by activating the Nrf2/HO-1 signaling pathway in mice after TBI.

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