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1.
Nature ; 608(7922): 421-428, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35922508

RESUMEN

Glucose uptake is essential for cancer glycolysis and is involved in non-shivering thermogenesis of adipose tissues1-6. Most cancers use glycolysis to harness energy for their infinite growth, invasion and metastasis2,7,8. Activation of thermogenic metabolism in brown adipose tissue (BAT) by cold and drugs instigates blood glucose uptake in adipocytes4,5,9. However, the functional effects of the global metabolic changes associated with BAT activation on tumour growth are unclear. Here we show that exposure of tumour-bearing mice to cold conditions markedly inhibits the growth of various types of solid tumours, including clinically untreatable cancers such as pancreatic cancers. Mechanistically, cold-induced BAT activation substantially decreases blood glucose and impedes the glycolysis-based metabolism in cancer cells. The removal of BAT and feeding on a high-glucose diet under cold exposure restore tumour growth, and genetic deletion of Ucp1-the key mediator for BAT-thermogenesis-ablates the cold-triggered anticancer effect. In a pilot human study, mild cold exposure activates a substantial amount of BAT in both healthy humans and a patient with cancer with mitigated glucose uptake in the tumour tissue. These findings provide a previously undescribed concept and paradigm for cancer therapy that uses a simple and effective approach. We anticipate that cold exposure and activation of BAT through any other approach, such as drugs and devices either alone or in combination with other anticancer therapeutics, will provide a general approach for the effective treatment of various cancers.


Asunto(s)
Tejido Adiposo Pardo , Frío , Metabolismo Energético , Neoplasias , Adipocitos/metabolismo , Tejido Adiposo Pardo/metabolismo , Animales , Glucemia/metabolismo , Terapia Combinada , Glucólisis , Humanos , Ratones , Neoplasias/metabolismo , Neoplasias/prevención & control , Neoplasias/terapia , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/prevención & control , Neoplasias Pancreáticas/terapia , Termogénesis/genética , Proteína Desacopladora 1/metabolismo
2.
Proc Natl Acad Sci U S A ; 120(29): e2303740120, 2023 07 18.
Artículo en Inglés | MEDLINE | ID: mdl-37428914

RESUMEN

Defining reliable surrogate markers and overcoming drug resistance are the most challenging issues for improving therapeutic outcomes of antiangiogenic drugs (AADs) in cancer patients. At the time of this writing, no biomarkers are clinically available to predict AAD therapeutic benefits and drug resistance. Here, we uncovered a unique mechanism of AAD resistance in epithelial carcinomas with KRAS mutations that targeted angiopoietin 2 (ANG2) to circumvent antivascular endothelial growth factor (anti-VEGF) responses. Mechanistically, KRAS mutations up-regulated the FOXC2 transcription factor that directly elevated ANG2 expression at the transcriptional level. ANG2 bestowed anti-VEGF resistance as an alternative pathway to augment VEGF-independent tumor angiogenesis. Most colorectal and pancreatic cancers with KRAS mutations were intrinsically resistant to monotherapies of anti-VEGF or anti-ANG2 drugs. However, combination therapy with anti-VEGF and anti-ANG2 drugs produced synergistic and potent anticancer effects in KRAS-mutated cancers. Together, these data demonstrate that KRAS mutations in tumors serve as a predictive marker for anti-VEGF resistance and are susceptible to combination therapy with anti-VEGF and anti-ANG2 drugs.


Asunto(s)
Carcinoma , Factores de Crecimiento Endotelial , Humanos , Factores de Crecimiento Endotelial/genética , Factor A de Crecimiento Endotelial Vascular/genética , Factor A de Crecimiento Endotelial Vascular/metabolismo , Proteínas Proto-Oncogénicas p21(ras)/genética , Proteínas Proto-Oncogénicas p21(ras)/metabolismo , Angiopoyetina 2/genética , Angiopoyetina 2/metabolismo , Angiopoyetina 1/metabolismo
3.
Proc Natl Acad Sci U S A ; 119(8)2022 02 22.
Artículo en Inglés | MEDLINE | ID: mdl-35181605

RESUMEN

Breast cancer is the most frequent malignancy in women worldwide, and triple-negative breast cancer (TNBC) patients have the worst prognosis and highest risk of recurrence. The therapeutic strategies for TNBC are limited. It is urgent to develop new methods to enhance the efficacy of TNBC treatment. Previous studies demonstrated that D-mannose, a hexose, can enhance chemotherapy in cancer and suppress the immunopathology of autoimmune diseases. Here, we show that D-mannose can significantly facilitate TNBC treatment via degradation of PD-L1. Specifically, D-mannose can activate AMP-activated protein kinase (AMPK) to phosphorylate PD-L1 at S195, which leads to abnormal glycosylation and proteasomal degradation of PD-L1. D-mannose-mediated PD-L1 degradation promotes T cell activation and T cell killing of tumor cells. The combination of D-mannose and PD-1 blockade therapy dramatically inhibits TNBC growth and extends the lifespan of tumor-bearing mice. Moreover, D-mannose-induced PD-L1 degradation also results in messenger RNA destabilization of DNA damage repair-related genes, thereby sensitizing breast cancer cells to ionizing radiation (IR) treatment and facilitating radiotherapy of TNBC in mice. Of note, the effective level of D-mannose can be easily achieved by oral administration in mice. Our study unveils a mechanism by which D-mannose targets PD-L1 for degradation and provides methods to facilitate immunotherapy and radiotherapy in TNBC. This function of D-mannose may be useful for clinical treatment of TNBC.


Asunto(s)
Antígeno B7-H1/metabolismo , Manosa/farmacología , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Proteínas Quinasas Activadas por AMP/efectos de los fármacos , Proteínas Quinasas Activadas por AMP/metabolismo , Animales , Antígeno B7-H1/efectos de los fármacos , Línea Celular Tumoral , Femenino , Humanos , Factores Inmunológicos/metabolismo , Inmunoterapia/métodos , Linfocitos Infiltrantes de Tumor/metabolismo , Manosa/metabolismo , Ratones , Ratones Endogámicos BALB C , Fosforilación , Proteolisis/efectos de los fármacos , Radioterapia/métodos , Linfocitos T/metabolismo , Neoplasias de la Mama Triple Negativas/metabolismo
4.
Proc Natl Acad Sci U S A ; 119(40): e2203307119, 2022 10 04.
Artículo en Inglés | MEDLINE | ID: mdl-36161914

RESUMEN

Brown adipose tissue (BAT) is a highly specialized adipose tissue in its immobile location and size during the entire adulthood. In response to cold exposure and other ß3-adrenoreceptor stimuli, BAT commits energy consumption by nonshivering thermogenesis (NST). However, the molecular machinery in controlling the BAT mass in adults is unknown. Here, we show our surprising findings that the BAT mass and functions can be manipulated in adult animals by controlling BAT adipocyte differentiation in vivo. Platelet-derived growth factor receptor α (PDGFα) expressed in BAT progenitor cells served a signaling function to avert adipose progenitor differentiation. Genetic and pharmacological loss-of-function of PDGFRα eliminated the differentiation barrier and permitted progenitor cell differentiation to mature and functional BAT adipocytes. Consequently, an enlarged BAT mass (megaBAT) was created by PDGFRα inhibition owing to increases of brown adipocyte numbers. Under cold exposure, a microRNA-485 (miR-485) was identified as a master suppressor of the PDGFRα signaling, and delivery of miR-485 also produced megaBAT in adult animals. Noticeably, megaBAT markedly improved global metabolism, insulin sensitivity, high-fat-diet (HFD)-induced obesity, and diabetes by enhancing NST. Together, our findings demonstrate that the adult BAT mass can be increased by blocking the previously unprecedented inhibitory signaling for BAT progenitor cell differentiation. Thus, blocking the PDGFRα for the generation of megaBAT provides an attractive strategy for treating obesity and type 2 diabetes mellitus (T2DM).


Asunto(s)
Adipocitos Marrones , Adipocitos , Adipogénesis , Tejido Adiposo Pardo , MicroARNs , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas , Adipocitos/citología , Adipocitos Marrones/metabolismo , Tejido Adiposo Pardo/citología , Tejido Adiposo Pardo/metabolismo , Animales , Diabetes Mellitus Tipo 2/terapia , Metabolismo Energético , MicroARNs/genética , MicroARNs/metabolismo , Obesidad/terapia , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/genética , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/metabolismo , Termogénesis/genética
5.
J Virol ; 97(4): e0188922, 2023 04 27.
Artículo en Inglés | MEDLINE | ID: mdl-37022174

RESUMEN

African swine fever (ASF) is a highly infectious disease caused by the African swine fever virus (ASFV) in swine. It is characterized by the death of cells in infected tissues. However, the molecular mechanism of ASFV-induced cell death in porcine alveolar macrophages (PAMs) remains largely unknown. In this study, transcriptome sequencing of ASFV-infected PAMs found that ASFV activated the JAK2-STAT3 pathway in the early stages and apoptosis in the late stages of infection. Meanwhile, the JAK2-STAT3 pathway was confirmed to be essential for ASFV replication. AG490 and andrographolide (AND) inhibited the JAK2-STAT3 pathway, promoted ASFV-induced apoptosis, and exerted antiviral effects. Additionally, CD2v promoted STAT3 transcription and phosphorylation as well as translocation into the nucleus. CD2v is the main envelope glycoprotein of the ASFV, and further investigations showed that CD2v deletion downregulates the JAK2-STAT3 pathway and promotes apoptosis to inhibit ASFV replication. Furthermore, we discovered that CD2v interacts with CSF2RA, which is a hematopoietic receptor superfamily member in myeloid cells and a key receptor protein that activates receptor-associated JAK and STAT proteins. In this study, CSF2RA small interfering RNA (siRNA) downregulated the JAK2-STAT3 pathway and promoted apoptosis to inhibit ASFV replication. Taken together, ASFV replication requires the JAK2-STAT3 pathway, while CD2v interacts with CSF2RA to regulate the JAK2-STAT3 pathway and inhibit apoptosis to facilitate virus replication. These results provide a theoretical basis for the escape mechanism and pathogenesis of ASFV. IMPORTANCE African swine fever is a hemorrhagic disease caused by the African swine fever virus (ASFV), which infects pigs of different breeds and ages, with a fatality rate of up to 100%. It is one of the key diseases affecting the global livestock industry. Currently, no commercial vaccines or antiviral drugs are available. Here, we show that ASFV replicates via the JAK2-STAT3 pathway. More specifically, ASFV CD2v interacts with CSF2RA to activate the JAK2-STAT3 pathway and inhibit apoptosis, thereby maintaining the survival of infected cells and promoting viral replication. This study revealed an important implication of the JAK2-STAT3 pathway in ASFV infection and identified a novel mechanism by which CD2v has evolved to interact with CSF2RA and maintain JAK2-STAT3 pathway activation to inhibit apoptosis, thus elucidating new information regarding the signal reprogramming of host cells by ASFV.


Asunto(s)
Virus de la Fiebre Porcina Africana , Receptores de Factor Estimulante de Colonias de Granulocitos y Macrófagos , Proteínas del Envoltorio Viral , Replicación Viral , Animales , Fiebre Porcina Africana/virología , Virus de la Fiebre Porcina Africana/genética , Apoptosis/genética , Porcinos , Replicación Viral/genética , Proteínas del Envoltorio Viral/metabolismo , Receptores de Factor Estimulante de Colonias de Granulocitos y Macrófagos/metabolismo , Janus Quinasa 2/genética , Janus Quinasa 2/metabolismo , Factor de Transcripción STAT3/genética , Factor de Transcripción STAT3/metabolismo , Interacciones Microbiota-Huesped , Regulación hacia Abajo
6.
Gastrointest Endosc ; 2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38583544

RESUMEN

BACKGROUND AND AIMS: Although commonly used for treating complications of chronic pancreatitis (CP), data on the frequency and factors associated with the use of pancreatic endotherapy (PET) are limited. Our aim was to define the utilization and factors predictive for receiving PET in a well-characterized CP cohort. METHODS: This is a cross-sectional analysis of data from PROCEED, a multicenter US cohort study of CP. PET modalities primarily consisted of ERCP. A treatment course was defined as the number of sessions performed for a specific indication. A repeat course was defined as PET >1 year after completion of the last course. Multivariable logistic regression identified predictive factors for receiving PET, and proportional rates model assessed risk factors for repeat PET. RESULTS: Of a total of 681 subjects, 238 (34.9%) received PET. Factors associated with receiving PET included female sex (OR: 1.26, 95% CI: 1.03-1.53), lower education (OR: 1.30, 95% CI: 1.04-1.62), income ≤ $50,000 per year (OR: 1.35, 95% CI: 1.07-1.71) and prior acute pancreatitis (AP) (OR: 1.74, 95% CI: 1.31, 2.32). 103/238 subjects (43.3%) underwent repeat PET at a median duration of 2 years with 23.1% receiving 2 courses, 9.7% receiving 3 courses, and 10.4% receiving 4+ courses. CONCLUSIONS: Nearly half of patients with CP who undergo PET received one or more repeat courses within 2-3 years. In addition to a prior history of AP, demographic and socioeconomic factors were associated with receiving PET.

7.
J Nanobiotechnology ; 22(1): 360, 2024 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-38907233

RESUMEN

Osteosarcoma (OS) derived small extracellular vesicles (OS-sEVs) have been shown to induce the formation of cancer-associated fibroblasts (CAFs), characterized by elevated pro-inflammatory factor expression and enhanced migratory and contractile abilities. These CAFs play a crucial role in priming lung metastasis by orchestrating the pre-metastatic niche (PMN) in the lung. Disrupting the communication between OS-sEVs and lung fibroblasts (LFs) emerges as a potent strategy to hinder OS pulmonary metastasis. Our previously established saponin-mediated cargo-elimination strategy effectively reduces the cancer-promoting ability of tumor-derived small extracellular vesicles (TsEVs) while preserving their inherent targeting capability. In this study, we observed that cargo-eliminated OS-sEVs (CE-sEVs) display minimal pro-tumoral and LFs activation potential, yet retain their ability to target LFs. The uptake of OS-sEVs by LFs can be concentration-dependently suppressed by CE-sEVs, preventing the conversion of LFs into CAFs and thus inhibiting PMN formation and pulmonary metastasis of OS. In summary, this study proposes a potential strategy to prevent LFs activation, PMN formation in the lung, and OS pulmonary metastasis through competitive inhibition of OS-sEVs' function by CE-sEVs.


Asunto(s)
Vesículas Extracelulares , Neoplasias Pulmonares , Osteosarcoma , Osteosarcoma/patología , Osteosarcoma/metabolismo , Vesículas Extracelulares/metabolismo , Neoplasias Pulmonares/secundario , Neoplasias Pulmonares/patología , Animales , Humanos , Ratones , Línea Celular Tumoral , Neoplasias Óseas/patología , Neoplasias Óseas/secundario , Neoplasias Óseas/metabolismo , Fibroblastos Asociados al Cáncer/metabolismo , Fibroblastos Asociados al Cáncer/patología , Ratones Endogámicos BALB C , Saponinas/farmacología , Ratones Desnudos , Movimiento Celular/efectos de los fármacos , Pulmón/patología
8.
J Biopharm Stat ; : 1-9, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38562017

RESUMEN

Utilization of historical data is increasingly common for gaining efficiency in the drug development and decision-making processes. The underlying issue of between-trial heterogeneity in clinical trials is a barrier in making these methods standard practice in the pharmaceutical industry. Common methods for historical borrowing discount the borrowed information based on the similarity between outcomes in the historical and current data. However, individual clinical trials and their outcomes are intrinsically heterogenous due to differences in study design, patient characteristics, and changes in standard of care. Additionally, differences in covariate distributions can produce inconsistencies in clinical outcome data between historical and current data when there may be a consistent covariate effect. In such scenario, borrowing historical data is still advantageous even though the population level outcome summaries are different. In this paper, we propose a covariate adjusted meta-analytic-predictive (CA-MAP) prior for historical control borrowing. A MAP prior is assigned to each covariate effect, allowing the amount of borrowing to be determined by the consistency of the covariate effects across the current and historical data. This approach integrates between-trial heterogeneity with covariate level heterogeneity to tune the amount of information borrowed. Our method is unique as it directly models the covariate effects instead of using the covariates to select a similar population to borrow from. In summary, our proposed patient-level extension of the MAP prior allows for the amount of historical control borrowing to depend on the similarity of covariate effects rather than similarity in clinical outcomes.

9.
Semin Cancer Biol ; 86(Pt 3): 251-261, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35307547

RESUMEN

Metastasis is the leading cause of cancer-associated mortality and the underlying mechanisms of cancer metastasis remain elusive. Both blood and lymphatic vasculatures are essential structures for mediating distal metastasis. The vasculature plays multiple functions, including accelerating tumor growth, sustaining the tumor microenvironment, supplying growth and invasive signals, promoting metastasis, and causing cancer-associated systemic disease. VEGF is one of the key angiogenic factors in tumors and participates in the initial stage of tumor development, progression and metastasis. Consequently, VEGF and its receptor-mediated signaling pathways have become one of the most important therapeutic targets for treating various cancers. Today, anti-VEGF-based antiangiogenic drugs (AADs) are widely used in the clinic for treating different types of cancer in human patients. Despite nearly 20-year clinical experience with AADs, the impact of these drugs on cancer metastasis and systemic disease remains largely unknown. In this review article, we focus our discussion on tumor VEGF in cancer metastasis and systemic disease and mechanisms underlying AADs in clinical benefits.


Asunto(s)
Linfangiogénesis , Neoplasias , Humanos , Neovascularización Patológica/tratamiento farmacológico , Neoplasias/etiología , Neoplasias/tratamiento farmacológico , Microambiente Tumoral , Inhibidores de la Angiogénesis/uso terapéutico
10.
Clin Gastroenterol Hepatol ; 21(7): 1781-1791.e4, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36191836

RESUMEN

BACKGROUND AND AIMS: Pain is a cardinal symptom of chronic pancreatitis (CP). Using Patient-Reported Outcomes Measurement Information System (PROMIS) measures, we characterized physical and mental health and symptom profiles of a well-defined cohort of individuals with CP and compared them with control subjects. Among patients with CP, we also examined associations between pain (intensity, temporal nature) and PROMIS symptom profiles and the prevalence of clinically significant psychological comorbidities. METHODS: We analyzed baseline data in 488 CP patients and 254 control subjects enrolled in PROCEED (Prospective Evaluation of Chronic Pancreatitis for Epidemiologic and Translational Studies), an ongoing longitudinal cohort study. Participants completed the PROMIS-Global Health, which captures global physical and mental health, and the PROMIS-29 profile, which captures 7 symptom domains. Self-reported pain was categorized by severity (none, mild-moderate, severe) and temporal nature (none, intermittent, constant). Demographic and clinical data were obtained from the PROCEED database. RESULTS: Pain was significantly associated with impairments in physical and mental health. Compared with participants with no pain, CP participants with severe pain (but not mild-moderate pain) had more decrements in each PROMIS domain in multivariable models (effect sizes, 2.54-7.03) and had a higher prevalence of clinically significant depression, anxiety, sleep disturbance, and physical disability (odds ratios, 2.11-4.74). Similar results were noted for constant pain (but not intermittent pain) for PROMIS domains (effect sizes, 4.08-10.37) and clinically significant depression, anxiety, sleep disturbance and physical disability (odds ratios, 2.80-5.38). CONCLUSIONS: Severe and constant pain are major drivers for poor psychological and physical health in CP. Systematic evaluation and management of psychiatric comorbidities and sleep disturbance should be incorporated into routine management of patients with CP. (ClinicalTrials.gov, Number: NCT03099850).


Asunto(s)
Dolor Crónico , Pancreatitis Crónica , Humanos , Estudios Longitudinales , Dolor Crónico/epidemiología , Pancreatitis Crónica/complicaciones , Pancreatitis Crónica/epidemiología , Salud Mental , Medición de Resultados Informados por el Paciente , Calidad de Vida
11.
Virol J ; 20(1): 158, 2023 07 19.
Artículo en Inglés | MEDLINE | ID: mdl-37468960

RESUMEN

African swine fever (ASF) is an acute infectious haemorrhagic fever of pigs caused by African swine fever virus (ASFV). Aloe-emodin (Ae) is an active ingredient of Chinese herbs with antiviral, anticancer, and anti-inflammatory effects. We investigated the antiviral activity and mechanism of action of Ae against ASFV using Real-time quantitative PCR (qPCR), western blotting, and indirect immunofluorescence assays. Ae significantly inhibited ASFV replication. Furthermore, transcriptomic analysis revealed that ASFV infection activated the NF-κB signaling pathway in the early stage and the apoptosis pathway in the late stage. Ae significantly downregulated the expression levels of MyD88, phosphor-NF-κB p65, and pIκB proteins as well as the mRNA levels of IL-1ß and IL-8 in porcine alveolar macrophages (PAMs) infected with ASFV, thereby inhibiting the activation of the NF-κB signaling pathway induced by ASFV. Flow cytometry and western blot analysis revealed that Ae significantly increased the percentage of ASFV-induced apoptotic cells. Additionally, Ae promoted apoptosis by upregulating the expression levels of cleaved-caspase3 and Bax proteins and downregulating the expression levels of Bcl-2 proteins. This suggests that Ae promotes apoptosis by inhibiting the NF-κB pathway, resulting in inhibition of ASFV replication. These findings have further improved therapeutic reserves for the prevention and treatment of ASF.


Asunto(s)
Virus de la Fiebre Porcina Africana , Fiebre Porcina Africana , Aloe , Emodina , Animales , Virus de la Fiebre Porcina Africana/genética , Aloe/metabolismo , Antivirales/farmacología , Apoptosis , Emodina/farmacología , FN-kappa B/metabolismo , Transducción de Señal , Porcinos , Replicación Viral
12.
Nano Lett ; 22(1): 196-202, 2022 01 12.
Artículo en Inglés | MEDLINE | ID: mdl-34935386

RESUMEN

Biofuel cells with good biocompatibility are promising to be used as the power source for flexible and wearable bioelectronics. We here report a type of highly flexible and stretchable biofuel cells, which are enabled by textile electrodes of graphene/carbon nanotubes (G/CNTs) composite and polymer hydrogel electrolyte. The CNT array covalently grown from a graphene layer not only can be served as a conducting substrate to immobilize enzyme molecules but also can provide efficient charge transport channels between the enzyme and graphene electrode. As a result, the developed biofuel cells deliver a high open-circuit voltage of 0.65 V and output power density of 64.2 µW cm-2, which are much higher than previously reported results. Benefiting from the unique textile structure of electrodes and the polymer hydrogel electrolyte, the biofuel cells exhibit high retention of power density after 400 bending cycles and even stretched to a high strain of 60%.


Asunto(s)
Fuentes de Energía Bioeléctrica , Nanotubos de Carbono , Electrodos , Electrólitos , Hidrogeles , Nanotubos de Carbono/química , Polímeros , Textiles
13.
Int J Mol Sci ; 24(7)2023 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-37047837

RESUMEN

Microbial fatty acids are synthesized by Type II fatty acid synthase and could be tailored by acyl-ACP thioesterase. With the prospects of medium-chain fatty-acid-derivative biofuels, the selectivity of thioesterase has been studied to control the fatty acid product chain length. Here, we report an alternative approach by manipulating the acyl carrier protein portion of acyl-ACP to switch the chain length propensity of the thioesterase. It was demonstrated that ChFatB2 from Cuphea hookeriana preferred C10-ACP to C8-ACP with ACP from E. coli, while converting preference to C8-ACP with ACP from Cuphea lanceolate. Circular dichroism (CD) results indicated that the C8-EcACP encountered a 34.4% α-helix increment compared to C10-EcACP, which resulted in an approximate binding affinity decrease in ChFatB2 compared to C10-EcACP. Similarly, the C10-ClACP2 suffered a 45% decrease in helix content compared to C8-ClACP2, and the conformational changes resulted in an 18% binding affinity decline with ChFatB2 compared with C10-ClACP2. In brief, the study demonstrates that the ACP portion of acyl-ACP contributes to the selectivity of acyl-ACP thioesterase, and the conformational changes of EcACP and ClACP2 switch the chain length preference of ChFatB2 between C8 and C10. The result provides fundamentals for the directed synthesis of medium-chain fatty acids based on regulating the conformational changes of ACPs.


Asunto(s)
Proteína Transportadora de Acilo , Escherichia coli , Proteína Transportadora de Acilo/metabolismo , Escherichia coli/metabolismo , Tioléster Hidrolasas/metabolismo , Ácidos Grasos/metabolismo
14.
J Environ Manage ; 325(Pt A): 116506, 2023 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-36270130

RESUMEN

N2O is regarded as an inevitable intermediate during nitrogen removal, especially for wastewater treatment plants where good operating conditions would be required to mitigate N2O releasing, which generally causes a high treatment cost. In this study, a novel bacterium capable of removing nitrogen without N2O accumulation was isolated and identified as Citrobacter freundii XY-1. The nitrogen removal characteristics, nitrogen removal pathway, bioaugmentation in different reactors as well as microbial diversity were investigated. Results showed that 99.42% of NH+ 4-N and 95% of total organic carbon could be removed within 48 h with the corresponding removal rates being 4.03 mg/(L·h) and 39.42 mg/(L·h), respectively. It was inferred that traditional denitrification and N2O generation do not exist in the pathway of removing nitrogen by XY-1 based on isotope analysis and functional genes detection. Bioaugmentations of XY-1 in both sequencing batch reactor and biological aerated filter significantly promoted the performances of nitrogen removal. The microbial diversity indicated that the relative abundance of strain XY-1 ranged from 45% to 66%, predominating throughout the running period. Overall, XY-1 could become an incredibly important candidate for the upgrading of wastewater treatment plants.


Asunto(s)
Desnitrificación , Nitrógeno , Nitrógeno/metabolismo , Nitrificación , Reactores Biológicos/microbiología , Aguas Residuales
15.
Gut ; 71(1): 129-147, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-33568427

RESUMEN

OBJECTIVE: Pancreatic ductal adenocarcinoma (PDAC) is the most lethal malignancy and lacks effective treatment. We aimed to understand molecular mechanisms of the intertwined interactions between tumour stromal components in metastasis and to provide a new paradigm for PDAC therapy. DESIGN: Two unselected cohorts of 154 and 20 patients with PDAC were subjected to correlation between interleukin (IL)-33 and CXCL3 levels and survivals. Unbiased expression profiling, and genetic and pharmacological gain-of-function and loss-of-function approaches were employed to identify molecular signalling in tumour-associated macrophages (TAMs) and myofibroblastic cancer-associated fibroblasts (myoCAFs). The role of the IL-33-ST2-CXCL3-CXCR2 axis in PDAC metastasis was evaluated in three clinically relevant mouse PDAC models. RESULTS: IL-33 was specifically elevated in human PDACs and positively correlated with tumour inflammation in human patients with PDAC. CXCL3 was highly upregulated in IL-33-stimulated macrophages that were the primary source of CXCL3. CXCL3 was correlated with poor survival in human patients with PDAC. Mechanistically, activation of the IL-33-ST2-MYC pathway attributed to high CXCL3 production. The highest level of CXCL3 was found in PDAC relative to other cancer types and its receptor CXCR2 was almost exclusively expressed in CAFs. Activation of CXCR2 by CXCL3 induced a CAF-to-myoCAF transition and α-smooth muscle actin (α-SMA) was uniquely upregulated by the CXCL3-CXCR2 signalling. Type III collagen was identified as the CXCL3-CXCR2-targeted adhesive molecule responsible for myoCAF-driven PDAC metastasis. CONCLUSIONS: Our work provides novel mechanistic insights into understanding PDAC metastasis by the TAM-CAF interaction and targeting each of these signalling components would provide an attractive and new paradigm for treating pancreatic cancer.


Asunto(s)
Fibroblastos Asociados al Cáncer/metabolismo , Carcinoma Ductal Pancreático/patología , Quimiocinas CXC/metabolismo , Neoplasias Pancreáticas/patología , Macrófagos Asociados a Tumores/metabolismo , Animales , Carcinoma Ductal Pancreático/mortalidad , Estudios de Cohortes , Humanos , Interleucina-33/metabolismo , Ratones Noqueados , Metástasis de la Neoplasia , Neoplasias Pancreáticas/mortalidad , Regulación hacia Arriba
16.
Proc Natl Acad Sci U S A ; 116(22): 10937-10942, 2019 05 28.
Artículo en Inglés | MEDLINE | ID: mdl-31085638

RESUMEN

Mirabegron (Myrbetriq) is a ß3-adrenoreceptor agonist approved for treating overactive bladder syndrome in human patients. This drug can activate brown adipose tissue (BAT) in adult humans and rodents through the ß3-adrenoreceptor-mediated sympathetic activation. However, the effect of the mirabegron, approved by the US Food and Drug Administration, on atherosclerosis-related cardiovascular disease is unknown. Here, we show that the clinical dose of mirabegron-induced BAT activation and browning of white adipose tissue (WAT) exacerbate atherosclerotic plaque development. In apolipoprotein E-/- (ApoE-/-) and low-density lipoprotein (LDL) receptor-/- (Ldlr-/-) mice, oral administration of clinically relevant doses of mirabegron markedly accelerates atherosclerotic plaque growth and instability by a mechanism of increasing plasma levels of both LDL-cholesterol and very LDL-cholesterol remnants. Stimulation of atherosclerotic plaque development by mirabegron is dependent on thermogenesis-triggered lipolysis. Genetic deletion of the critical thermogenesis-dependent protein, uncoupling protein 1, completely abrogates the mirabegron-induced atherosclerosis. Together, our findings suggest that mirabegron may trigger cardiovascular and cerebrovascular diseases in patients who suffer from atherosclerosis.


Asunto(s)
Acetanilidas/farmacología , Tejido Adiposo Pardo/efectos de los fármacos , Aterosclerosis/patología , Lipólisis/efectos de los fármacos , Tiazoles/farmacología , Agentes Urológicos/farmacología , Tejido Adiposo Pardo/metabolismo , Tejido Adiposo Blanco/efectos de los fármacos , Tejido Adiposo Blanco/metabolismo , Animales , Aterosclerosis/fisiopatología , LDL-Colesterol/sangre , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados para ApoE , Receptores de LDL/genética
17.
Sensors (Basel) ; 22(13)2022 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-35808441

RESUMEN

Continuous passive motion (CPM) machines are commonly used after various knee surgeries, but information on tibiofemoral forces (TFFs) during CPM cycles is limited. This study aimed to explore the changing trend of TFFs during CPM cycles under various ranges of motion (ROM) and body weights (BW) by establishing a two-dimensional mathematical model. TFFs were estimated by using joint angles, foot load, and leg−foot weight. Eleven healthy male participants were tested with ROM ranging from 0° to 120°. The values of the peak TFFs during knee flexion were higher than those during knee extension, varying nonlinearly with ROM. BW had a significant main effect on the peak TFFs and tibiofemoral shear forces, while ROM had a limited effect on the peak TFFs. No significant interaction effects were observed between BW and ROM for each peak TFF, whereas a strong linear correlation existed between the peak tibiofemoral compressive forces (TFCFs) and the peak resultant TFFs (R2 = 0.971, p < 0.01). The proposed method showed promise in serving as an input for optimizing rehabilitation devices.


Asunto(s)
Pie , Articulación de la Rodilla , Fenómenos Biomecánicos , Humanos , Rodilla , Masculino , Rango del Movimiento Articular , Estrés Mecánico
18.
Dev Biol ; 457(2): 206-214, 2020 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-30796893

RESUMEN

The choriocapillaris is an exceptionally high density, two-dimensional, sheet-like capillary network, characterized by the highest exchange rate of nutrients for waste products per area in the organism. These unique morphological and physiological features are critical for supporting the extreme metabolic requirements of the outer retina needed for vision. The developmental mechanisms and processes responsible for generating this unique vascular network remain, however, poorly understood. Here we take advantage of the zebrafish as a model organism for gaining novel insights into the cellular dynamics and molecular signaling mechanisms involved in the development of the choriocapillaris. We show for the first time that zebrafish have a choriocapillaris highly similar to that in mammals, and that it is initially formed by a novel process of synchronized vasculogenesis occurring simultaneously across the entire outer retina. This initial vascular network expands by un-inhibited sprouting angiogenesis whereby all endothelial cells adopt tip-cell characteristics, a process which is sustained throughout embryonic and early post-natal development, even after the choriocapillaris becomes perfused. Ubiquitous sprouting was maintained by continuous VEGF-VEGFR2 signaling in endothelial cells delaying maturation until immediately before stages where vision becomes important for survival, leading to the unparalleled high density and lobular structure of this vasculature. Sprouting was throughout development limited to two dimensions by Bruch's membrane and the sclera at the anterior and posterior surfaces respectively. These novel cellular and molecular mechanisms underlying choriocapillaris development were recapitulated in mice. In conclusion, our findings reveal novel mechanisms underlying the development of the choriocapillaris during zebrafish and mouse development. These results may explain the uniquely high density and sheet-like organization of this vasculature.


Asunto(s)
Coroides/irrigación sanguínea , Coroides/embriología , Neovascularización Fisiológica/fisiología , Retina/embriología , Animales , Diferenciación Celular/fisiología , Ratones , Ratones Endogámicos BALB C , Transducción de Señal/fisiología , Factor A de Crecimiento Endotelial Vascular/metabolismo , Receptor 2 de Factores de Crecimiento Endotelial Vascular/metabolismo , Pez Cebra , Proteínas de Pez Cebra/metabolismo
19.
Water Sci Technol ; 83(7): 1691-1702, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33843752

RESUMEN

In this study, spent mushroom substrates (SMSs) were fermented anaerobically at room temperature to gain liquid SMSs (LSMSs) that were used to remove nitrogen from the piggery wastewater with a low C/N ratio in a sequencing batch reactor (SBR) and solid SMSs (SSMSs) that were utilized to adsorb Pb2+ from Pb2+-containing wastewater in a fixed-bed reactor (FBR). After LSMSs supplement, the removal efficiency of both total nitrogen (TN) and NH+4-N increased from around 50% to 60-80%. High-throughput sequencing results presented an obvious change in microbial diversity, and some functional microorganisms like Zoogloea and Hydrogenophaga predominated to promote nitrogen removal. Pb2+ did not emerge from the effluent until 240 min with the corresponding concentration being less than 3 mg/L when using 30-day SSMSs as adsorbents, and it was demonstrated to be appropriate to use the Thomas model to predict Pb2+ sorption on SSMSs. Although various functional groups played a role in binding ions, the carboxyl group was proved to contribute most to Pb2+ adsorption. These results certified that the anaerobically fermented SMSs are decidedly suitable for wastewater treatment.


Asunto(s)
Agaricales , Nitrógeno , Adsorción , Reactores Biológicos , Desnitrificación , Plomo , Nitrógeno/análisis , Eliminación de Residuos Líquidos , Aguas Residuales
20.
J Cell Mol Med ; 24(1): 640-654, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31667951

RESUMEN

Endogenous neurogenesis holds promise for brain repair and long-term functional recovery after ischaemic stroke. However, the effects of exosomes from human urine-derived stem cells (USC-Exos) in neurogenesis remain unclear. This study aimed to investigate whether USC-Exos enhanced neurogenesis and promoted functional recovery in brain ischaemia. By using an experimental stroke rat model, we found that intravenous injection of USC-Exos enhanced neurogenesis and alleviated neurological deficits in post-ischaemic stroke rats. We used neural stem cells (NSCs) subjected to oxygen-glucose deprivation/reoxygenation (OGD/R) as an in vitro model of ischaemic stroke. The in vitro results suggested that USC-Exos promoted both proliferation and neuronal differentiation of NSCs after OGD/R. Notably, a further mechanism study revealed that the pro-neurogenesis effects of USC-Exos may be partially attributed to histone deacetylase 6 (HDAC6) inhibition via the transfer of exosomal microRNA-26a (miR-26a). Taken together, this study indicates that USC-Exos can be used as a novel promising strategy for brain ischaemia, which highlights the application of USC-Exos.


Asunto(s)
Isquemia Encefálica/terapia , Exosomas/trasplante , Histona Desacetilasa 6/metabolismo , MicroARNs/genética , Células-Madre Neurales/citología , Neurogénesis , Accidente Cerebrovascular/terapia , Orina/citología , Animales , Isquemia Encefálica/genética , Isquemia Encefálica/metabolismo , Isquemia Encefálica/patología , Exosomas/metabolismo , Histona Desacetilasa 6/genética , Humanos , Masculino , Células-Madre Neurales/metabolismo , Ratas , Ratas Sprague-Dawley , Accidente Cerebrovascular/genética , Accidente Cerebrovascular/metabolismo , Accidente Cerebrovascular/patología
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