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1.
EBioMedicine ; 103: 105129, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38640836

RESUMO

BACKGROUND: Poly(ADP-ribose) polymerase (PARP) inhibitors have emerged as promising chemotherapeutic drugs primarily against BRCA1/2-associated tumours, known as synthetic lethality. However, recent clinical trials reported patients' survival benefits from PARP inhibitor treatments, irrelevant to homologous recombination deficiency. Therefore, revealing the therapeutic mechanism of PARP inhibitors beyond DNA damage repair is urgently needed, which can facilitate precision medicine. METHODS: A CRISPR-based knock-in technology was used to establish stable BRCA1 mutant cancer cells. The effects of PARP inhibitors on BRCA1 mutant cancer cells were evaluated by biochemical and cell biological experiments. Finally, we validated its in vivo effects in xenograft and patient-derived xenograft (PDX) tumour mice. FINDINGS: In this study, we uncovered that the majority of clinical BRCA1 mutations in breast cancers were in and near the middle of the gene, rather than in essential regions for DNA damage repair. Representative mutations such as R1085I and E1222Q caused transient extra spindle poles during mitosis in cancer cells. PAR, which is synthesized by PARP2 but not PARP1 at mitotic centrosomes, clustered these transient extra poles, independent of DNA damage response. Common PARP inhibitors could effectively suppress PARP2-synthesized PAR and induce cell senescence by abrogating the correction of mitotic extra-pole error. INTERPRETATION: Our findings uncover an alternative mechanism by which PARP inhibitors efficiently suppress tumours, thereby pointing to a potential new therapeutic strategy for centrosome error-related tumours. FUNDING: Funded by National Natural Science Foundation of China (NSFC) (T2225006, 82272948, 82103106), Beijing Municipal Natural Science Foundation (Key program Z220011), and the National Clinical Key Specialty Construction Program, P. R. China (2023).


Assuntos
Proteína BRCA1 , Senescência Celular , Centrossomo , Dano ao DNA , Inibidores de Poli(ADP-Ribose) Polimerases , Ensaios Antitumorais Modelo de Xenoenxerto , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico , Humanos , Animais , Centrossomo/metabolismo , Centrossomo/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Senescência Celular/efeitos dos fármacos , Camundongos , Proteína BRCA1/genética , Linhagem Celular Tumoral , Feminino , Mutação , Reparo do DNA/efeitos dos fármacos , Modelos Animais de Doenças , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Neoplasias da Mama/metabolismo , Poli(ADP-Ribose) Polimerases/metabolismo , Poli(ADP-Ribose) Polimerases/genética , Poli(ADP-Ribose) Polimerase-1/metabolismo , Poli(ADP-Ribose) Polimerase-1/antagonistas & inibidores , Poli(ADP-Ribose) Polimerase-1/genética
2.
Eur J Pharmacol ; 968: 176408, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38367684

RESUMO

We have developed a diphtheria toxin-based recombinant human CCR4-IL2 bispecific immunotoxin (CCR4-IL2-IT) for targeted therapy of cutaneous T-cell lymphoma (CTCL). CCR4-IL2-IT demonstrated superior efficacy in an immunodeficient mouse CTCL model. Recently, we have compared the in vivo efficacy of CCR4-IL2-IT versus Brentuximab (FDA approved leading drug in CTCL market) in the same immunodeficient mouse CTCL model. The comparison demonstrated that CCR4-IL2-IT was significantly more effective than Brentuximab. In this study, we have performed non-GLP (Good Laboratory Practice) toxicology, pharmacokinetics, immunogenicity studies of CCR4-IL2-IT in both rats and minipigs. CCR4-IL2-IT demonstrated excellent safety profiles in both rats and minipigs. The maximum tolerated dose of CCR4-IL2-IT was determined as 0.4 mg/kg in both rats and minipigs. Complete blood count and chemistry analysis did not show significant difference for all measured parameters between the blood samples of pre-injection versus post-injection from the five-day toxicology studies of CCT4-IL2-IT in both rats and minipigs. Histology analysis did not show difference between the PBS treatment group versus CCR4-IL2-IT treatment group at 50 µg/kg in both rats and minipigs. The half-life of CCR4-IL2-IT was determined as about 45 min in rats and 30 min in minipigs. The antibodies against CCR4-IL2-IT were detected in about two weeks after CCR4-IL2-IT treatment. CCR4-IL2-IT did not induce cytokine release syndrome in a peripheral blood mononuclear cell derived humanized mouse model. The depletion of CCR4+ cell and CD25+ cell (two target cell populations of CCR4-IL2-IT) was observed in minipigs. The excellent safety profile promoted us to further develop CCR4-IL2-IT towards clinical trials.


Assuntos
Antineoplásicos , Imunotoxinas , Camundongos , Ratos , Humanos , Animais , Suínos , Imunotoxinas/farmacologia , Imunotoxinas/uso terapêutico , Porco Miniatura , Interleucina-2 , Leucócitos Mononucleares , Receptores CCR4 , Anticorpos Monoclonais/farmacologia , Camundongos SCID , Antineoplásicos/uso terapêutico
3.
Proc Natl Acad Sci U S A ; 121(8): e2314128121, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38359291

RESUMO

Aberrant lysine lactylation (Kla) is associated with various diseases which are caused by excessive glycolysis metabolism. However, the regulatory molecules and downstream protein targets of Kla remain largely unclear. Here, we observed a global Kla abundance profile in colorectal cancer (CRC) that negatively correlates with prognosis. Among lactylated proteins detected in CRC, lactylation of eEF1A2K408 resulted in boosted translation elongation and enhanced protein synthesis which contributed to tumorigenesis. By screening eEF1A2 interacting proteins, we identified that KAT8, a lysine acetyltransferase that acted as a pan-Kla writer, was responsible for installing Kla on many protein substrates involving in diverse biological processes. Deletion of KAT8 inhibited CRC tumor growth, especially in a high-lactic tumor microenvironment. Therefore, the KAT8-eEF1A2 Kla axis is utilized to meet increased translational requirements for oncogenic adaptation. As a lactyltransferase, KAT8 may represent a potential therapeutic target for CRC.


Assuntos
Neoplasias Colorretais , Biossíntese de Proteínas , Humanos , Carcinogênese/genética , Transformação Celular Neoplásica , Neoplasias Colorretais/genética , Catálise , Microambiente Tumoral , Histona Acetiltransferases
4.
J Nutr Biochem ; 124: 109489, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-37926400

RESUMO

Epidemiological studies suggest an association between folate deficiency (FD) and cervical squamous cell carcinoma (SCC) progression. However, the underlying mechanism is unclear. Our study showed that FD-driven downregulation of miR-375 promoted proliferation of SCC SiHa cells and progression of xenograft tumors developed from SiHa; however, the exact mechanism of this process remained unclear. The current study aimed to elucidate the underlying mechanisms by which FD promotes the progression of SiHa cells by downregulating miR-375 expression. The results showed that miR-375 acted as a suppressor of SCC and inhibited the proliferation, migration, and invasion of SiHa cells. The FZD4 gene was identified as a target gene of miR-375, which can reverse the anti-onco effect of miR-375 and promote the proliferation and migration of SiHa cells. Furthermore, the regulatory effects of miR-375 and FZD4 on SiHa cells may be achieved by activating the ß-catenin signaling pathway. Moreover, FD may regulate the expression of miR-375 by regulating its DNA methylation level in the promoter region. In conclusion, our study reveals that FD regulates the miR-375/FZD4 axis by increasing the methylation of the miR-375 promoter, thereby activating ß-catenin signaling to promote SiHa cells progression. This study may provide new insights into the role of folic acid in the prevention and treatment of SCC.


Assuntos
Carcinoma de Células Escamosas , MicroRNAs , Neoplasias do Colo do Útero , Feminino , Humanos , beta Catenina/genética , beta Catenina/metabolismo , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , MicroRNAs/metabolismo , Linhagem Celular Tumoral , Neoplasias do Colo do Útero/genética , Via de Sinalização Wnt , Ácido Fólico/farmacologia , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Movimento Celular , Receptores Frizzled/genética
5.
ACS Appl Mater Interfaces ; 16(1): 166-177, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38143309

RESUMO

Tumor-associated platelets can bind to tumor cells and protect circulating tumor cells from NK-mediated immune surveillance. Tumor-associated platelets secrete cytokines to induce the epithelial-mesenchymal transition (EMT) in tumor cells, which promotes tumor metastasis. Combining chemotherapeutic agents with antiplatelet drugs can reduce the occurrence of metastasis, but the systemic application of chemotherapeutic agents and antiplatelet drugs is prone to causing serious side effects. Therefore, delivering drugs to the tumor microthrombus site for long-lasting inhibition is a problem that needs to be addressed. Here, we show that small molecule peptide nanoparticles containing the Cys-Arg-Glu-Lys-Ala (CREKA) peptide can deliver the platelet inhibitor dipyridamole (DIP) and the chemotherapeutic drug paclitaxel (PTX) to tumor tissues, thereby inhibiting tumor-associated platelet function while killing tumor cells. The drug-loaded nanoparticles PD/Pep1 inhibited platelet-tumor cell interactions, were effectively taken up by tumor cells, and underwent morphological transformation induced by alkaline phosphatase (ALP) to prolong the retention time of the drugs. After intravenous injection, PD/Pep1 can target tumors and inhibit tumor metastasis. Thus, this small molecule peptide nanoformulation provides a simple strategy for efficient drug delivery and shows promise as a novel cancer therapy platform.


Assuntos
Nanopartículas , Células Neoplásicas Circulantes , Humanos , Paclitaxel , Inibidores da Agregação Plaquetária/farmacologia , Dipiridamol/farmacologia , Peptídeos/farmacologia , Peptídeos/química , Nanopartículas/química , Linhagem Celular Tumoral
6.
Biomater Adv ; 154: 213650, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37857084

RESUMO

The treatment of breast cancer relies heavily on chemotherapy, but chemotherapy is limited by the disadvantages of poor targeting, susceptibility to extracellular matrix (ECM) interference and a short duration of action in tumor cells. To address these limitations, we developed an amphipathic peptide containing an RGD motif, Pep1, that encapsulated paclitaxel (PTX) and losartan potassium (LP) to form the drug-loaded peptide PL/Pep1. PL/Pep1 self-assembled into spherical nanoparticles (NPs) under normal physiological conditions and transformed into aggregates containing short nanofibers at acidic pH. The RGD peptide facilitated tumor targeting and the aggregates prolonged drug retention in the tumor, which allowed more drug to reach and accumulate in the tumor tissue to promote apoptosis and remodel the tumor microenvironment. The results of in vitro and in vivo experiments confirmed the superiority of PL/Pep1 in terms of targeting, prolonged retention and facilitated penetration for antitumor therapy. In conclusion, amphipathic peptides as coloaded drug carriers are a new platform and strategy for breast cancer chemotherapy.


Assuntos
Neoplasias da Mama , Nanopartículas , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Paclitaxel/uso terapêutico , Paclitaxel/farmacologia , Peptídeos/uso terapêutico , Portadores de Fármacos , Microambiente Tumoral
7.
Cell Rep Med ; 4(6): 101061, 2023 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-37267943

RESUMO

Ovarian cancer (OC) causes high mortality in women because of ineffective biomarkers for early diagnosis. Here, we perform metabolomics analysis on an initial training set of uterine fluid from 96 gynecological patients. A seven-metabolite-marker panel consisting of vanillylmandelic acid, norepinephrine, phenylalanine, beta-alanine, tyrosine, 12-S-hydroxy-5,8,10-heptadecatrienoic acid, and crithmumdiol is established for detecting early-stage OC. The panel is further validated in an independent sample set from 123 patients, discriminating early OC from controls with an area under the curve (AUC) of 0.957 (95% confidence interval [CI], 0.894-1). Interestingly, we find elevated norepinephrine and decreased vanillylmandelic acid in most OC cells, resulting from excess 4-hydroxyestradiol that antagonizes the catabolism of norepinephrine by catechol-O-methyltransferase. Moreover, exposure to 4-hydroxyestradiol induces cellular DNA damage and genomic instability that could lead to tumorigenesis. Thus, this study not only reveals metabolic features in uterine fluid of gynecological patients but also establishes a noninvasive approach for the early diagnosis of OC.


Assuntos
Catecol O-Metiltransferase , Neoplasias Ovarianas , Humanos , Feminino , Ácido Vanilmandélico , Detecção Precoce de Câncer , Neoplasias Ovarianas/diagnóstico , Neoplasias Ovarianas/genética , Metaboloma , Norepinefrina
8.
FEBS Open Bio ; 13(7): 1309-1319, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37157185

RESUMO

Cutaneous T-cell lymphoma (CTCL) encompasses two main subtypes: mycosis fungoides and Sezary syndrome. Global response rates for the systemic treatment of mycosis fungoides and Sezary syndrome are approximately 30%, and none of these treatments are thought to be curative. C-C chemokine receptor type 4 (CCR4) and CD25 are encouraging targets for the treatment of CTCL and are individually targeted by mogamulizumab and denileukin diftitox, respectively. We developed a novel CCR4-IL2 bispecific immunotoxin (CCR4-IL2 IT) targeting both CCR4 and CD25. CCR4-IL2 IT demonstrated superior efficacy against CCR4+ CD25+ CD30+ CTCL in an immunodeficient NSG mouse tumor model. Investigative New Drug-enabling studies of CCR4-IL2 IT are ongoing, including Good Manufacturing Practice production and toxicology studies. In this study, we compared the in vivo efficacy of CCR4-IL2 IT versus the US Food and Drug Administration-approved drug, brentuximab, using an immunodeficient mouse CTCL model. We demonstrated that CCR4-IL2 IT was significantly more effective in prolonging survival than brentuximab, and combination treatment of CCR4-IL2 IT and brentuximab was more effective than brentuximab or CCR4-IL2 IT alone in an immunodeficient NSG mouse CTCL model. Thus, CCR4-IL2 IT is a promising novel therapeutic drug candidate for CTCL treatment.


Assuntos
Antineoplásicos , Imunotoxinas , Linfoma Cutâneo de Células T , Micose Fungoide , Síndrome de Sézary , Neoplasias Cutâneas , Estados Unidos , Animais , Camundongos , Imunotoxinas/farmacologia , Imunotoxinas/uso terapêutico , Síndrome de Sézary/tratamento farmacológico , Síndrome de Sézary/patologia , Interleucina-2/uso terapêutico , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/patologia , Linfoma Cutâneo de Células T/tratamento farmacológico , Linfoma Cutâneo de Células T/patologia , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Micose Fungoide/tratamento farmacológico , Micose Fungoide/patologia , Anticorpos Monoclonais
9.
Medicine (Baltimore) ; 101(46): e31857, 2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36401492

RESUMO

BACKGROUND: To compare the efficacy and feasibility of using a modified Glasgow coma scale (GCS) score of 13 or 15 as the criterion for switching chronic obstructive pulmonary disease (COPD) patients with respiratory failure to sequential invasive-noninvasive ventilation. METHODS: COPD patients with respiratory failure who had undergone endotracheal intubation and invasive mechanical ventilation (IMV) between June 2017 and June 2020 at 4 different hospitals in China were included. A total of 296 patients were randomly divided into 2 groups. In group A, the patients were extubated and immediately placed on noninvasive ventilation (NIV) when the modified GCS score reached 13. In group B, the same was done when the modified GCS score reached 15. RESULTS: No significant differences in the mean blood pressure, oxygenation index, arterial partial pressure of oxygen, and arterial partial pressure of carbon dioxide were seen between groups A and B before extubation and 3 hours after NIV. The re-intubation times were also similar in the 2 groups. Compared to group B, the length of hospital stay, incidence of ventilator associated pneumonia, and time of invasive ventilation were all significantly lower in group A (P = .041, .001, <.001). CONCLUSION: Using a modified GCS score of 13 as the criterion for switching from IMV to NIV can significantly reduce the duration of IMV, length of hospital stay, and incidence of ventilator associated pneumonia in COPD patients with respiratory failure.


Assuntos
Pneumonia Associada à Ventilação Mecânica , Doença Pulmonar Obstrutiva Crônica , Insuficiência Respiratória , Humanos , Respiração Artificial/efeitos adversos , Escala de Coma de Glasgow , Insuficiência Respiratória/terapia , Insuficiência Respiratória/complicações , Doença Pulmonar Obstrutiva Crônica/complicações , Doença Pulmonar Obstrutiva Crônica/terapia
10.
Oncol Lett ; 24(6): 422, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36284647

RESUMO

The aim of the present study was to explore the effects of BRAF-activated non-protein coding RNA (BANCR) on pancreatic microlymphangiogenesis in pancreatic cancer (PC) and its molecular mechanism under hypoxic conditions. Reverse transcription-quantitative PCR (RT-qPCR) was used to detect the expression of BANCR in SW1990 and PANC-1 PC cell lines under normoxic and hypoxic conditions. Subsequently, the expression of BANCR in the PC cells was knocked down using small interfering RNAs (siRNAs). Western blotting and RT-qPCR analyses were performed to detect the expression of hypoxia-inducible factor (HIF-1α), VEGF-C and VEGFR-3 in the transfected cells. In addition, the transfected PC cells were co-cultured with human lymphatic endothelial cells and the lymphatic microvessel density (MLVD) was detected under normal and hypoxic conditions. Furthermore, HIF-1α expression in the PC cells was knocked down using siRNAs, and VEGF-C and VEGFR-3 mRNA expression in the HIF-1α knockdown cells was detected using RT-qPCR. The results showed that the expression of BANCR in the SW1990 and PANC-1 PC cell lines was significantly higher than that in human pancreatic duct endothelial cells. Additionally, the expression of BANCR was significantly increased in PC cells under hypoxic conditions compared with normoxic conditions. The MLVD of PC cells under hypoxic conditions was significantly higher compared with that under normoxic conditions, and the MLVD in the si-BANCR group was lower than that in the si-NC group, indicating that si-BANCR downregulated MLVD. These results indicate that BANCR positively regulated the expression of HIF-1α in PC cells at the transcriptional and translational levels. Finally, the expression levels of VEGF-C and VEGFR-3 in PC cells were significantly reduced when BANCR or HIF-1α expression was knocked down. In conclusion, the results demonstrate that the expression of BANCR in PC cells was significantly increased under hypoxic conditions and suggest that BANCR promoted tumor cell lymphangiogenesis by upregulating the HIF-1α/VEGF-C/VEGFR-3 pathway, which plays an important role in the process of PC lymph node metastasis.

11.
Cancer Res ; 82(14): 2576-2592, 2022 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-35648393

RESUMO

Recent work has made it clear that pericentriolar material (PCM), the matrix of proteins surrounding centrioles, contributes to most functions of centrosomes. Given the occurrence of centrosome amplification in most solid tumors and the unconventional survival of these tumor cells, it is tempting to hypothesize that gel-like mitotic PCM would cluster extra centrosomes to defend against mitotic errors and increase tumor cell survival. However, because PCM lacks an encompassing membrane, is highly dynamic, and is physically connected to centrioles, few methods can decode the components of this microscale matrix. In this study, we took advantage of differential labeling between two sets of APEX2-centrosome reactions to design a strategy for acquiring the PCM proteome in living undisturbed cells without synchronization treatment, which identified 392 PCM proteins. Localization of ubiquitination promotion proteins away from PCM was a predominant mechanism to maintain the large size of PCM for centrosome clustering during mitosis in cancer cells. Depletion of PCM gene kinesin family member 20A (KIF20A) caused centrosome clustering failure and apoptosis in cancer cells in vitro and in vivo. Thus, our study suggests a strategy for targeting a wide range of tumors exhibiting centrosome amplification and provides a proteomic resource for future mining of PCM proteins. SIGNIFICANCE: This study identifies the proteome of pericentriolar material and reveals therapeutic vulnerabilities in tumors bearing centrosome amplification.


Assuntos
Proteoma , Proteômica , Centríolos/metabolismo , Centrossomo/metabolismo , Humanos , Mitose , Proteoma/metabolismo
12.
Front Cell Dev Biol ; 10: 889656, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35517499

RESUMO

Breast cancer type 1 susceptibility protein (BRCA1) is essential for homologous recombination repair of DNA double-strand breaks. Loss of BRCA1 is lethal to embryos due to extreme genomic instability and the activation of p53-dependent apoptosis. However, the apoptosis is resisted in BRCA1-deficient cancer cells even though their p53 is proficient. In this study, by analysis of transcriptome data of ovarian cancer patients bearing BRCA1 defects in TCGA database, we found that cAMP signaling pathway was significantly activated. Experimentally, we found that BRCA1 deficiency caused an increased expression of ADRB1, a transmembrane receptor that can promote the generation of cAMP. The elevated cAMP not only inhibited DNA damage-induced apoptosis through abrogating p53 accumulation, but also suppressed the proliferation of cytotoxic T lymphocytes by enhancing the expression of immunosuppressive factors DKK1. Inhibition of ADRB1 effectively killed cancer cells by abolishing the apoptotic resistance. These findings uncover a novel mechanism of apoptotic resistance in BRCA1-deficient ovarian cancer cells and point to a potentially new strategy for treating BRCA1-mutated tumors.

13.
Transbound Emerg Dis ; 69(2): 249-253, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35001535

RESUMO

Rabies is a serious public health issue in China, with over 95% of human infections transmitted by dogs. As part of a routine surveillance carried out in the Inner Mongolia Autonomous Region (IMAR) between 2019 and 2021, 80 of 95 suspected rabies cases in domestic animals (dogs, livestock) and wild carnivores (foxes, badgers, a raccoon dog) were confirmed as rabies virus (RABV) positive. Phylogenetic analysis of RABVs of the 80 cases based on complete N genes showed that 97.5% (78/80) of the virus strains belonged to the Cosmopolitan (steppe-type) clade, with one in each of Arctic-related (AL2) and Asian (SEA1) clades. The data show that infected foxes have become a major transmission source of rabies in China, second only to dogs, and play a pivotal role in animal rabies epizootics in the north and northwest of the country. The recent spread of fox rabies to other animal species presents an increasing threat to public health and emphasizes the importance of animal rabies surveillance.


Assuntos
Doenças do Cão , Vírus da Raiva , Raiva , Animais , Animais Domésticos , Animais Selvagens , China/epidemiologia , Doenças do Cão/epidemiologia , Cães , Raposas , Filogenia , Raiva/epidemiologia , Raiva/veterinária , Vírus da Raiva/genética
14.
Cell Mol Gastroenterol Hepatol ; 13(2): 565-582, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34756982

RESUMO

BACKGROUND & AIMS: Nonalcoholic fatty liver disease is a frequent cause of hepatic dysfunction and is now a global epidemic. This ailment can progress to an advanced form called nonalcoholic steatohepatitis (NASH) and end-stage liver disease. Currently, the molecular basis of NASH pathogenesis is poorly understood, and no effective therapies exist to treat NASH. These shortcomings are due to the paucity of experimental NASH models directly relevant to humans. METHODS: We used chimeric mice with humanized liver to investigate nonalcoholic fatty liver disease in a relevant model. We carried out histologic, biochemical, and molecular approaches including RNA-Seq. For comparison, we used side-by-side human NASH samples. RESULTS: Herein, we describe a "humanized" model of NASH using transplantation of human hepatocytes into fumarylacetoacetate hydrolase-deficient mice. Once fed a high-fat diet, these mice develop NAFLD faithfully, recapitulating human NASH at the histologic, cellular, biochemical, and molecular levels. Our RNA-Seq analyses uncovered that a variety of important signaling pathways that govern liver homeostasis are profoundly deregulated in both humanized and human NASH livers. Notably, we made the novel discovery that hepatocyte growth factor (HGF) function is compromised in human and humanized NASH at several levels including a significant increase in the expression of the HGF antagonists known as NK1/NK2 and marked decrease in HGF activator. Based on these observations, we generated a potent, human-specific, and stable agonist of human MET that we have named META4 (Metaphor) and used it in the humanized NASH model to restore HGF function. CONCLUSIONS: Our studies revealed that the humanized NASH model recapitulates human NASH and uncovered that HGF-MET function is impaired in this disease. We show that restoring HGF-MET function by META4 therapy ameliorates NASH and reinstates normal liver function in the humanized NASH model. Our results show that the HGF-MET signaling pathway is a dominant regulator of hepatic homeostasis.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Animais , Dieta Hiperlipídica , Hepatócitos/metabolismo , Camundongos , Hepatopatia Gordurosa não Alcoólica/patologia
15.
China CDC Wkly ; 3(39): 815-818, 2021 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-34594998

RESUMO

INTRODUCTION: Rabies is a fatal zoonotic infectious disease that poses a serious threat to public health in China. Since 2005, a National Animal Rabies Surveillance System has been operating to understand the rabies situation in animals in China with a view to control and eventually eliminate dog-mediated human rabies. METHODS: From 2010, the brain tissues of dogs, livestock, and wild animals showing rabies-like clinical signs were collected and tested by the National Reference Laboratory (NRL) for Animal Rabies to analyze the epidemiological characteristics of rabies, including animal species, geographic distribution, and transmission sources. Over the same period, clinically suspected animal rabies cases were collected by Animal Disease Control Centers through the National Animal Disease Monitoring Information Platform (NADMIP) and then reported in the Veterinary Bulletin. RESULTS: During 2010-2020, 170 of 212 suspected animal rabies cases were submitted to and confirmed by NRL as rabies virus-positive. Of these confirmed cases dogs, especially free-roaming and ownerless dogs in rural areas, were major transmission hosts (71/170). A total of 51 infected dogs attacked humans with 45 biting more than one person. The dog cases were reported all year round, but with significantly more in spring and summer. The majority of livestock rabies cases (70/80) being caused by rabid wild foxes in Xinjiang and Inner Mongolia revealed that foxes play a pivotal role in animal rabies epizootics in the north and northwest of the country. CONCLUSION: Dogs were the main transmission sources of rabies in China, and along with the recent increase of rabies in foxes and other wildlife, presented an increasing threat to livestock and public health.

16.
Phys Rev E ; 104(2-1): 024503, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34525580

RESUMO

The spatial correlations of entangled polymer dynamics are examined by molecular dynamics simulations and neutron spin-echo spectroscopy. Due to the soft nature of topological constraints, the initial spatial decays of intermediate scattering functions of entangled chains are, to the first approximation, surprisingly similar to those of an unentangled system in the functional forms. However, entanglements reveal themselves as a long tail in the reciprocal-space correlations, implying a weak but persistent dynamic localization in real space. Comparison with a number of existing theoretical models of entangled polymers suggests that they cannot fully describe the spatial correlations revealed by simulations and experiments. In particular, the strict one-dimensional diffusion idea of the original tube model is shown to be flawed. The dynamic spatial correlation analysis demonstrated in this work provides a useful tool for interrogating the dynamics of entangled polymers. Lastly, the failure of the investigated models to even qualitatively predict the spatial correlations of collective single-chain density fluctuations points to a possible critical role of incompressibility in polymer melt dynamics.

17.
Acta Pharmacol Sin ; 42(12): 2144-2154, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34017067

RESUMO

Mitochondria are essential organelles that provide energy for mammalian cells and participate in multiple functions, such as signal transduction, cellular differentiation, and regulation of apoptosis. Compared with the mitochondria in somatic cells, oocyte mitochondria have an additional level of importance since they are required for germ cell maturation, dysfunction in which can lead to severe inherited disorders. Thus, a systematic proteomic profile of oocyte mitochondria is urgently needed to support the basic and clinical research, but the acquisition of such a profile has been hindered by the rarity of oocyte samples and technical challenges associated with capturing mitochondrial proteins from live oocytes. Here, in this work, using proximity labeling proteomics, we established a mitochondria-specific ascorbate peroxidase (APEX2) reaction in live GV-stage mouse oocytes and identified a total of 158 proteins in oocyte mitochondria. This proteome includes intrinsic mitochondrial structural and functional components involved in processes associated with "cellular respiration", "ATP metabolism", "mitochondrial transport", etc. In addition, mitochondrial proteome capture after oocyte exposure to the antitumor chemotherapeutic cisplatin revealed differential changes in the abundance of several oocyte-specific mitochondrial proteins. Our study provides the first description of a mammalian oocyte mitochondrial proteome of which we are aware, and further illustrates the dynamic shifts in protein abundance associated with chemotherapeutic agents.


Assuntos
Antineoplásicos/farmacologia , Cisplatino/farmacologia , Mitocôndrias/efeitos dos fármacos , Proteínas Mitocondriais/metabolismo , Oócitos/efeitos dos fármacos , Proteoma/metabolismo , Animais , Ascorbato Peroxidases/metabolismo , Feminino , Camundongos , Camundongos Endogâmicos ICR , Células NIH 3T3 , Proteômica/métodos
18.
Phys Rev E ; 103(2-1): 022609, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33736070

RESUMO

The study of liquid dynamics at mesoscopic scales is still strewn with difficulty due to limitations in theory and experiment. Historically, significant attention has been given to the analysis of space-time correlation functions and their frequency-Fourier transforms at a few discrete wave numbers. The massive computing power afforded by modern high performance computing clusters and the advent of a wide-angle neutron spin-echo spectrometer, however, have unlocked a more intuitive and fruitful approach to this problem. Using molecular dynamics simulations, here we demonstrate the benefits of spatiotemporally mapping intermediate scattering functions on a dense grid of correlation times and wave numbers. Four model systems are investigated: a Lennard-Jones liquid, a coarse-grained bead-spring polymer, a molten sodium chloride, and a poly(ethylene oxide) melt. We show that the spatiotemporal mapping approach is particularly useful for elucidating the mesoscopic dynamics in these liquids, where several underlying mechanisms, such as molecular relaxations, hydrodynamic modes, and nonhydrodynamic excitations, are potentially at play. Compared to the traditional method, direct visualization of density space-time correlation functions on two-dimensional color maps permits appraisals of complicated dynamical behavior at mesoscales in a global manner. For example, the scaling relations between space and time for different types of molecular motions can be straightforwardly identified on these plots, without any model-dependent analysis. Additionally, we show how theoretical ideas regarding collective mesoscopic dynamics, such as the classical hydrodynamic theory, the convolution approximation, and a recently proposed phenomenological model, can be discussed in terms of the global features of spatiotemporal maps of intermediate scattering functions. The new perspective offered by the spatiotemporal mapping method should prove useful for the study of liquid dynamics in general.

19.
Exp Ther Med ; 20(2): 1441-1446, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32742377

RESUMO

Sequential invasive-noninvasive ventilation (NIV) improves the outcomes of patients with respiratory failure caused by acute exacerbation of chronic obstructive pulmonary disease (AECOPD); however, there is no clear consensus on the optimal timing of the switch to sequential invasive-NIV in these patients. In the present study, a potential role for the modified Glasgow Coma Scale (GCS) score to guide sequential weaning was investigated. Patients with AECOPD and respiratory failure were prospectively recruited from three study centers (Wenling Hospital Affiliated to Wenzhou Medical University, the First Affiliated Hospital of Wenzhou Medical University and Changsha Central Hospital) between January 1st 2016 and December 31st 2018. Patients were randomly assigned to group A and B, with the switching point for sequential weaning strategy in the two groups being a modified GCS score ≥13 and 10 points, respectively. Each group included 240 patients. Baseline demographic characteristics were comparable in the two groups. The duration of invasive mechanical ventilation (IMV) in group A was significantly shorter than that in group B. However, there were no significant between-group differences with respect to the incidence of re-intubation, ventilator-associated pneumonia, in-hospital mortality or the length of hospital stay. Use of a modified GCS score ≥13 as the switching point for sequential invasive-NIV may help decrease the duration of IMV in patients with AECOPD and respiratory failure.

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