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1.
Cell ; 175(6): 1561-1574.e12, 2018 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-30449620

RESUMO

The molecular mediator and functional significance of meal-associated brown fat (BAT) thermogenesis remains elusive. Here, we identified the gut hormone secretin as a non-sympathetic BAT activator mediating prandial thermogenesis, which consequentially induces satiation, thereby establishing a gut-secretin-BAT-brain axis in mammals with a physiological role of prandial thermogenesis in the control of satiation. Mechanistically, meal-associated rise in circulating secretin activates BAT thermogenesis by stimulating lipolysis upon binding to secretin receptors in brown adipocytes, which is sensed in the brain and promotes satiation. Chronic infusion of a modified human secretin transiently elevates energy expenditure in diet-induced obese mice. Clinical trials with human subjects showed that thermogenesis after a single-meal ingestion correlated with postprandial secretin levels and that secretin infusions increased glucose uptake in BAT. Collectively, our findings highlight the largely unappreciated function of BAT in the control of satiation and qualify BAT as an even more attractive target for treating obesity.


Assuntos
Adipócitos Marrons/metabolismo , Tecido Adiposo Marrom/metabolismo , Ingestão de Alimentos , Secretina/metabolismo , Termogênese , Adipócitos Marrons/citologia , Tecido Adiposo Marrom/citologia , Animais , Células HEK293 , Humanos , Lipólise , Camundongos , Camundongos Knockout , Camundongos Obesos , Secretina/genética
2.
PLoS Pathog ; 20(3): e1012113, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38547316

RESUMO

Chronic viral infections cause T cell dysfunction in both animal models and human clinical settings, thereby affecting the ability of the host immune system to clear viral pathogens and develop proper virus-specific immune memory. However, the impact of chronic viral infections on the host's immune memory to other pathogens has not been well described. In this study, we immunized mice with recombinant Listeria monocytogenes expressing OVA (Lm-OVA) to generate immunity to Lm and allow analysis of OVA-specific memory T (Tm) cells. We then infected these mice with lymphocytic choriomeningitis virus (LCMV) strain Cl-13 which establishes a chronic infection. We found that chronically infected mice were unable to protect against Listeria re-challenge. OVA-specific Tm cells showed a progressive loss in total numbers and in their ability to produce effector cytokines in the context of chronic LCMV infection. Unlike virus-specific T cells, OVA-specific Tm cells from chronically infected mice did not up-regulate the expression of inhibitory receptors, a hallmark feature of exhaustion in virus-specific T cells. Finally, OVA-specific Tm cells failed to mount a robust recall response after bacteria re-challenge both in the chronically infected and adoptively transferred naïve hosts. These results show that previously established bacteria-specific Tm cells become functionally impaired in the setting of an unrelated bystander chronic viral infection, which may contribute to poor immunity against other pathogens in the host with chronic viral infection.


Assuntos
Coriomeningite Linfocítica , Viroses , Humanos , Animais , Camundongos , Linfócitos T CD8-Positivos , Memória Imunológica , Vírus da Coriomeningite Linfocítica , Citocinas , Camundongos Endogâmicos C57BL
3.
Antimicrob Agents Chemother ; : e0012424, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38690893

RESUMO

As an obligate aerobe, Mycobacterium tuberculosis relies on its branched electron transport chain (ETC) for energy production through oxidative phosphorylation. Regimens targeting ETC exhibit promising potential to enhance bactericidal activity against M. tuberculosis and hold the prospect of shortening treatment duration. Our previous research demonstrated that the bacteriostatic drug candidate TB47 (T) inhibited the growth of M. tuberculosis by targeting the cytochrome bc1 complex and exhibited synergistic activity with clofazimine (C). Here, we found synergistic activities between C and sudapyridine (S), a structural analog of bedaquiline (B). S has shown similar anti-tuberculosis efficacy and may share a mechanism of action with B, which inhibits ATP synthesis and the energy metabolism of bacteria. We evaluated the efficacy of SCT in combination with linezolid (L) or pyrazinamide (Z) using a well-established murine model of tuberculosis. Compared to the BPa(pretomanid)L regimen, SCT and SCTL demonstrated similar bactericidal and sterilizing activities. There was no significant difference in activity between SCT and SCTL. In contrast, SCZ and SCTZ showed much higher activities, with none of the 15 mice experiencing relapse after 2 months of treatment with either SCZ or SCTZ. However, T did not contribute to the activity of the SCZ. Our findings emphasize the efficacy and the potential clinical significance of combination therapy with ETC inhibitors. Additionally, cross-resistance exists not only between S and B but also between S/B and C. This is supported by our findings, as spontaneous S-resistant mutants exhibited mutations in Rv0678, which are associated with cross-resistance to B and C.

4.
Toxicol Appl Pharmacol ; 482: 116799, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38160893

RESUMO

Doxorubicin (DOX) is one of the most widely used antineoplastic drugs with known cardiotoxicity while other organ toxicity, such as hepatotoxicity is not well defined. This study was to explore the role of nicotinamide adenine dinucleotide (NAD+) in DOX-induced hepatotoxicity. DOX (20 mg/kg) induced acute liver injury and oxidative stress in C57BL/6 J mice at 48 h. Notably, the expression of nuclear factor erythroid 2-related factor 2 (Nrf2) and NAD(P)H dehydrogenase quinone 1 (NQO1) were downregulated. NAD+ deficiency was confirmed due to DOX exposure. Mechanistically, the downregulation of nicotinamide mononucleotide adenylyl transferase 1 (NMNAT1), NMNAT2 and NMNAT3, while no alteration of nicotinamide phosphoribosyl transferase was proved. As a consequence of NAD+ deficiency, the expression of poly-ADP-ribose polymerase1 (PARP1), CD38 and Sirtuin1 (SIRT1) were reduced. Furthermore, supplementation of NAD+ (200 mg/kg/day) or its precursor nicotinamide mononucleotide (NMN) (500 mg/kg/day) alleviated liver injury, attenuated oxidative stress, and elevated the downregulation of Nrf2 and NQO1. More importantly, compromised expression of NMNAT1-3, PARP1, CD38 and SIRT1 were improved by NAD+ and NMN. In conclusion, NAD+ deficiency due to NMNATs expression inhibition may attribute to the pathogenesis of DOX-induced hepatotoxicity, thus providing new insights for mitigating DOX side effects.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , NAD , Camundongos , Animais , NAD/metabolismo , Mononucleotídeo de Nicotinamida/farmacologia , Sirtuína 1/metabolismo , Fator 2 Relacionado a NF-E2 , Camundongos Endogâmicos C57BL , Doxorrubicina/toxicidade , Doença Hepática Induzida por Substâncias e Drogas/etiologia
5.
Proc Natl Acad Sci U S A ; 118(30)2021 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-34282012

RESUMO

The Qinghai-Tibetan Plateau, with low precipitation, low oxygen partial pressure, and temperatures routinely dropping below -30 °C in winter, presents several physiological challenges to its fauna. Yet it is home to many endemic mammalian species, including the plateau pika (Ochotona curzoniae). How these small animals that are incapable of hibernation survive the winter is an enigma. Measurements of daily energy expenditure (DEE) using the doubly labeled water method show that pikas suppress their DEE during winter. At the same body weight, pikas in winter expend 29.7% less than in summer, despite ambient temperatures being approximately 25 °C lower. Combined with resting metabolic rates (RMRs), this gives them an exceptionally low metabolic scope in winter (DEE/RMRt = 1.60 ± 0.30; RMRt is resting metabolic rate at thermoneutrality). Using implanted body temperature loggers and filming in the wild, we show that this is achieved by reducing body temperature and physical activity. Thyroid hormone (T3 and T4) measurements indicate this metabolic suppression is probably mediated via the thyroid axis. Winter activity was lower at sites where domestic yak (Bos grunniens) densities were higher. Pikas supplement their food intake at these sites by eating yak feces, demonstrated by direct observation, identification of yak DNA in pika stomach contents, and greater convergence in the yak/pika microbiotas in winter. This interspecific coprophagy allows pikas to thrive where yak are abundant and partially explains why pika densities are higher where domestic yak, their supposed direct competitors for food, are more abundant.


Assuntos
Aclimatação , Altitude , Metabolismo Basal , Metabolismo Energético , Fezes/química , Lagomorpha/fisiologia , Estações do Ano , Animais , Tibet
6.
Proteome Sci ; 21(1): 13, 2023 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-37740197

RESUMO

BACKGROUND: DCM is a common cardiomyopathy worldwide, which is characterized by ventricular dilatation and systolic dysfunction. DCM is one of the most widespread diseases contributing to sudden death and heart failure. However, our understanding of its molecular mechanisms is limited because of its etiology and underlying mechanisms. Hence, this study explored the underlying molecular mechanism of dilated cardiomyopathy through integrative analysis of data mining, iTRAQ-PRM proteomics and bioinformatics METHODS: DCM target genes were downloaded from the public databases. Next, DCM was induced in 20 rats by 8 weeks doxorubicin treatment (2.5 mg/kg/week). We applied isobaric tags for a relative and absolute quantification (iTRAQ) coupled with proteomics approach to identify differentially expressed proteins (DEPs) in myocardial tissue. After association analysis of the DEPs and the key target genes, subsequent analyses, including functional annotation, pathway enrichment, validation, were performed. RESULTS: Nine hundred thirty-five genes were identified as key target genes from public databases. Meanwhile, a total of 782 DEPs, including 348 up-regulated and 434 down-regulated proteins, were identified in our animal experiment. The functional annotation of these DEPs revealed complicated molecular mechanisms including TCA cycle, Oxidative phosphorylation, Cardiac muscle contraction. Moreover, the DEPs were analyzed for association with the key target genes screened in the public dataset. We further determined the importance of these three pathways. CONCLUSION: Our results demonstrate that TCA cycle, Oxidative phosphorylation, Cardiac muscle contraction played important roles in the detailed molecular mechanisms of DCM.

7.
EMBO Rep ; 22(7): e51289, 2021 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-34056831

RESUMO

The recruitment of thermogenic brite adipocytes within white adipose tissue attenuates obesity and metabolic comorbidities, arousing interest in understanding the underlying regulatory mechanisms. The molecular network of brite adipogenesis, however, remains largely unresolved. In this light, long noncoding RNAs (lncRNAs) emerged as a versatile class of modulators that control many steps within the differentiation machinery. Leveraging the naturally varying propensities of different inbred mouse strains for white adipose tissue browning, we identify the nuclear lncRNA Ctcflos as a pivotal orchestrator of thermogenic gene expression during brite adipocyte differentiation. Mechanistically, Ctcflos acts as a pleiotropic regulator, being essential for the transcriptional recruitment of the early core thermogenic regulatory program and the modulation of alternative splicing to drive brite adipogenesis. This is showcased by Ctcflos-regulated gene transcription and splicing of the key browning factor Prdm16 toward the isoform that is specific for the thermogenic gene program. Conclusively, our findings emphasize the mechanistic versatility of lncRNAs acting at several independent levels of gene expression for effective regulation of key differentiation factors to direct cell fate and function.


Assuntos
Adipogenia , RNA Longo não Codificante , Adipogenia/genética , Tecido Adiposo Marrom/metabolismo , Tecido Adiposo Branco/metabolismo , Processamento Alternativo , Animais , Camundongos , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Termogênese
8.
J Integr Neurosci ; 22(1): 21, 2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36722232

RESUMO

BACKGROUND: Epilepsy is a disease caused by paroxysmal abnormal supersynchronous electrical activity of brain neurons, and it is also one of the most common illnesses in neurology. Among the causes, hippocampal sclerosis may be one of the main causes of temporal lobe epilepsy. However, the pathogenesis of hippocampal sclerosis in epilepsy remains unclear. METHODS: We established an epilepsy model by intraperitoneal injection of pentetrazol (PTZ) into Sprague-Dawley rats, and applied isobaric tags for relative and absolute quantitation (iTRAQ) technology to identify differentially expressed proteins (DEPs) in the hippocampus. We quantified a total of 3782 proteins. DEPs were defined as proteins with a fold change >1.2 (or <0.83) and a Q value (p-adjusted) <0.05. RESULTS: Comparing the epilepsy group and the control group, we identified 170 DEPs, comprising 109 upregulated and 61 downregulated proteins. According to bioinformatics analysis, the DEPs were primarily involved in long-term potentiation, the calcium signalling pathway, aldosterone synthesis and secretion, carbon metabolism, and dopaminergic synapses. Four of these proteins were validated using parallel reaction monitoring (PRM), including Glud1, Atp1a2, Prkcg and Arpc3. CONCLUSIONS: Our research results may provide further insight into the molecular pathology of hippocampal injury in epilepsy.


Assuntos
Epilepsia do Lobo Temporal , Epilepsia , Esclerose Hipocampal , Ratos , Animais , Ratos Sprague-Dawley , Proteômica , Epilepsia/induzido quimicamente , Epilepsia do Lobo Temporal/induzido quimicamente , Hipocampo
9.
Artigo em Inglês | MEDLINE | ID: mdl-37126199

RESUMO

Primary angiitis of the central nervous system (PACNS) is a rare and fatal cerebral vasculitis mainly involving the arteriole of the pia mater, cerebral cortex, and spinal cord. It has an insidious onset atypical symptoms. In this paper, we reported an unexpected death due to cerebral hemorrhage caused by PACNS. According to the typical clinical manifestations (headache, dizziness, weakness of the limbs, temporary blurred vision, etc.) and pathological examination (wide degeneration and fibrinoid necrosis of blood vessel walls with inflammatory cell infiltration), as well as hematoxylin-eosin staining, immunohistochemistry for CD15 + and gram staining, we finally determined that the patient died due to cerebral vascular rupture and hemorrhage caused by PACNS. This case illustrates the value and key points of autopsy in evaluating sudden deaths.

10.
Artigo em Inglês | MEDLINE | ID: mdl-37542619

RESUMO

Lung cancer is a high degree of malignancy. Although surgery, radiotherapy, and chemotherapy have made significant progress and become general methods of clinical treatment, the overall survival rate is still low. In recent years, targeted therapy and immunotherapy have a rapid development in the clinical treatment of tumors. Among them, natural killer (NK) cells have the advantages of rapid killing of diseased cells and low risk of graft-versus-host reaction. It is considered a great vector for chimeric antigen receptors (CARs), making them have good application prospects in tumor immunotherapy. However, its clinical application in lung cancer needs further research. Herein, we reported a case of a lung cancer patient undergoing CAR-NK cell immunotherapy after resection, which caused a cytokine storm and sudden death after the fourth treatment. This case report provides a reference for the forensic examination of cadavers that died after immunotherapy and challenges the clinical application of cell immunotherapy.

11.
Forensic Sci Med Pathol ; 19(3): 393-397, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-36180659

RESUMO

In patients with known lung squamous cell carcinoma, it is necessary to be alert to the presence of cancer cell infiltration in the large blood vessels and the heart. In this report, we report a case of a 49-year-old man who was previously diagnosed with squamous cell carcinoma of the lung, underwent autoimmune cell therapy, and was diagnosed posthumously with lung cancer invading the aorta and heart, resulting in severe cardiac tamponade. This case illustrates the value and key points of autopsy in evaluating sudden deaths.


Assuntos
Carcinoma de Células Escamosas , Tamponamento Cardíaco , Neoplasias Pulmonares , Masculino , Humanos , Pessoa de Meia-Idade , Tamponamento Cardíaco/etiologia , Tamponamento Cardíaco/patologia , Neoplasias Pulmonares/patologia , Carcinoma de Células Escamosas/patologia , Pulmão/patologia , Aorta/patologia
12.
Int J Exp Pathol ; 103(5): 190-197, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35527237

RESUMO

The purpose of the present study was to investigate the expression of α-SMA and SM22α in airway smooth muscle (ASM) of bronchioles from children younger than 14 years who died of acute interstitial pneumonia (AIP). This is based upon the hypothesis that as contractile marker proteins α-SMA and SM22α can serve as an index of the overcontractile phenotype of ASM that is seen in AIP. Lung tissue samples of children were obtained from autopsies and divided into the AIP group (55.9% male and 44.1% female, between 0.4 and 132 months old, n = 34) and the control group (60% male and 40% female, between 2 and 156 months old, n = 10). We recorded the post-mortem interval (PMI), height, clinical symptoms and abdominal fat thickness (AFT) of each case. Haematoxylin-and-eosin-stained sections were used to examine the luminal area and observe the morphological changes in the bronchioles. Immunohistochemistry and Masson's trichrome staining were used to detect the expression of contractile marker proteins and the degree of pulmonary fibrosis respectively. Compared with the control group, the luminal areas of bronchioles in the AIP group were smaller (p < .001). The expression differences in α-SMA and SM22α between the two groups were statistically significant (p = .01 and p = .02 respectively). Also, there was no significant correlation of the contractile marker proteins expression with PMI, height, clinical symptoms and AFT. The collagen deposition difference in lung between the two groups was not statistically significant (p = .224). These findings suggest that enhancement of ASM contractile function appears to be involved in the death mechanism of children with AIP, which affords more insights into the understanding of AIP.


Assuntos
Síndrome de Hamman-Rich , Actinas/metabolismo , Adolescente , Criança , Pré-Escolar , Colágeno/metabolismo , Proteínas Contráteis/metabolismo , Amarelo de Eosina-(YS)/metabolismo , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Músculo Liso/metabolismo
13.
Bioorg Med Chem Lett ; 71: 128824, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-35636648

RESUMO

Multidrug resistant tuberculosis (MDR-TB) remains a major human health challenge. Bedaquiline was approved in 2012 by the US FDA, and listed by WHO as a treatment for multidrug-resistant tuberculosis (MDR-TB) in 2018. However, the side effects of bedaquiline including the risk of unexplained mortality, QTc prolongation and hepatotoxicity limit its wide clinical use. Based on bedaquiline, we describe herein discovery and development of a novel diarylpyridine series, which led to identification of WX-081 (sudapyridine, 21l). It displayed excellent anti-mycobacterial activity against M. tuberculosis H37Rv in vitro and in vivo and low cytotoxicity; additionally WX-081 had excellent pharmacokinetic parameters in animals, better lung exposure and lower QTc prolongation potential compared to bedaquiline. WX-081 is currently under clinical phase II development (NCT04608955).


Assuntos
Síndrome do QT Longo , Mycobacterium tuberculosis , Tuberculose Resistente a Múltiplos Medicamentos , Animais , Antituberculosos/farmacologia , Antituberculosos/uso terapêutico , Síndrome do QT Longo/induzido quimicamente , Síndrome do QT Longo/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico
14.
BMC Infect Dis ; 22(1): 72, 2022 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-35057735

RESUMO

BACKGROUND: Guillain-Barre syndrome (GBS) is a rare neurological complication of brucellosis, and neurobrucellosis is the most common, but they have many similarities in clinical manifestations. Many clinicians are accustomed to merely explaining the manifestations of nervous system involvement with neurobrucellosis, but they ignore the possibility of GBS, and this leads to misdiagnosis, untimely treatment, and serious consequences. CASE PRESENTATION: A 55-year-old male patient was admitted to The First Affiliated Hospital of Harbin Medical University for intermittent fever, fatigue, and waist pain more than three months. Brucellosis was diagnosed from the blood test. Although anti-brucella treatment was given at the time of diagnosis, the disease continued to progress. At the time of the cerebrospinal fluid systematic physical examination and the neuroelectrophysiological test, acute motor sensory axonal neuropathy was diagnosed. The patient was given immediately administered immunoglobulin therapy. After three months of systemic treatment, the patient's muscle strength of the distal limbs gradually recovered. The numbness of the limbs eased slowly, and urination function and respiratory function returned to normal. He could sit by himself. CONCLUSIONS: The possibility of GBS should be closely monitored for when a brucellosis patient shows typical clinical manifestations of progressive muscle weakness, protein-cell separation of the cerebral spinal fluid, and typical demyelinating sensorimotor polyneuropathy.


Assuntos
Brucella , Brucelose , Síndrome de Guillain-Barré , Brucelose/complicações , Brucelose/diagnóstico , Brucelose/tratamento farmacológico , Eletromiografia , Síndrome de Guillain-Barré/diagnóstico , Síndrome de Guillain-Barré/tratamento farmacológico , Síndrome de Guillain-Barré/etiologia , Humanos , Masculino , Pessoa de Meia-Idade
15.
World J Surg ; 46(5): 1122-1133, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35275232

RESUMO

BACKGROUND: With the global pandemic of obesity and nonalcoholic fatty liver disease (NAFLD), the incidence of cirrhosis associated with nonalcoholic steatohepatitis (NASH) has greatly increased. This study aimed to evaluate the efficacy and safety of bariatric surgery in obese cirrhotic patients. METHODS: PubMed, EMBASE, and the Cochrane Library were searched for relevant studies. Effectiveness outcomes were weight loss, remission of comorbidities, and improvement in liver function. Safety outcomes were procedural complications and mortality. RESULTS: A total of 15 studies were included in this meta-analysis. Patients with compensated cirrhosis lost weight significantly after surgery, and the percentage of excess weight loss was 60.44 (95% CI, 44.34 to 76.55). Bariatric surgery resulted in remission of NAFLD in 57.9% (95% CI, 27.5% to 88.3%), T2DM in 58.4% (95% CI, 48.4% to 68.4%), hypertension in 53.1% (95% CI, 43% to 63.3%), dyslipidemia in 59.8% (95% CI, 41.1% to 78.5%) of patients with cirrhosis. Bariatric surgery reduced the levels of alanine aminotransferase and aspartate aminotransferase. The incidence of surgical complications in patients with cirrhosis was about 19.2% (95% CI, 11.7% to 26.6%), which was higher than that in patients without cirrhosis (OR 2.67 [95% CI, 1.26 to 5.67]). Patients with cirrhosis had an overall mortality rate of 1.3%, and the mortality rates for compensated cirrhosis and decompensated cirrhosis were 0.9% and 18.2%, respectively. CONCLUSIONS: Bariatric surgery is effective for weight loss, remission of comorbidities, and reversal of liver damage. Although cirrhotic patients have a higher risk of complications and death, bariatric surgery is relatively safe for well-compensated cirrhosis.


Assuntos
Cirurgia Bariátrica , Hepatopatia Gordurosa não Alcoólica , Obesidade Mórbida , Cirurgia Bariátrica/efeitos adversos , Cirurgia Bariátrica/métodos , Humanos , Cirrose Hepática/complicações , Cirrose Hepática/cirurgia , Hepatopatia Gordurosa não Alcoólica/complicações , Obesidade/complicações , Obesidade/cirurgia , Obesidade Mórbida/cirurgia , Redução de Peso
16.
Int J Mol Sci ; 23(5)2022 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-35269549

RESUMO

Mitochondrial uncoupling protein 1 (UCP1) is the crucial mechanistic component of heat production in classical brown fat and the newly identified beige or brite fat. Thermogenesis inevitably comes at a high energetic cost and brown fat, ultimately, is an energy-wasting organ. A constrained strategy that minimizes brown fat activity unless obligate will have been favored during natural selection to safeguard metabolic thriftiness. Accordingly, UCP1 is constitutively inhibited and is inherently not leaky without activation. It follows that increasing brown adipocyte number or UCP1 abundance genetically or pharmacologically does not lead to an automatic increase in thermogenesis or subsequent metabolic consequences in the absence of a plausible route of concomitant activation. Despite its apparent obviousness, this tenet is frequently ignored. Consequently, incorrect conclusions are often drawn from increased BAT or brite/beige depot mass, e.g., predicting or causally linking beneficial metabolic effects. Here, we highlight the inherently inactive nature of UCP1, with a particular emphasis on the molecular brakes and releases of UCP1 activation under physiological conditions. These controls of UCP1 activity represent potential targets of therapeutic interventions to unlock constraints and efficiently harness the energy-expending potential of brown fat to prevent and treat obesity and associated metabolic disorders.


Assuntos
Tecido Adiposo Marrom/metabolismo , Proteína Desacopladora 1/metabolismo , Tecido Adiposo Bege/metabolismo , Animais , Metabolismo Energético , Humanos , Lipólise , Termogênese
17.
Am J Physiol Endocrinol Metab ; 320(2): E333-E345, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33252252

RESUMO

We studied the metabolic phenotype of a novel Ucp1-LUC-iRFP713 knock-in reporter gene mouse model originally generated to monitor endogenous Ucp1 gene expression. Both reporter mice and reporter cells reliably reflected Ucp1 gene expression in vivo and in vitro. We here report an unexpected reduction in UCP1 content in homozygous knock-in (KI) reporter mice. As a result, the thermogenic capacity of KI mice stimulated by norepinephrine was largely blunted, making them more sensitive to an acute cold exposure. In return, these reporter mice with reduced UCP1 expression enabled us to investigate the physiological role of UCP1 in the prevention of weight gain. We observed no substantial differences in body mass across the three genotypes, irrespective of the type of diet or the ambient temperature, possibly due to the insufficient UCP1 activation. Indeed, activation of UCP1 by daily injection of the selective ß3-adrenergic receptor agonist CL316,243 resulted in significantly greater reduction of body weight in wild-type mice than in KI mice. Taken together, we conclude that the intact expression of UCP1 is essential for cold-induced thermogenesis but the presence of UCP1 per se does not protect mice from diet-induced obesity.NEW & NOTEWORTHY To study the functional role of UCP1-dependent brown adipose tissue thermogenesis for energy balance, new animal models are needed. By metabolic phenotyping of a novel mouse model with low UCP1 levels in brown fat, we demonstrate that the susceptibility to diet-induced obesity is not increased despite impaired cold-induced thermogenic capacity. Brown fat requires pharmacological activation to promote negative energy balance in diet-induced obese mice.


Assuntos
Tecido Adiposo Marrom/patologia , Tecido Adiposo Branco/patologia , Dieta Hiperlipídica , Obesidade/patologia , Proteína Desacopladora 1/fisiologia , Tecido Adiposo Marrom/metabolismo , Tecido Adiposo Branco/metabolismo , Animais , Metabolismo Energético , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Obesos , Obesidade/etiologia , Obesidade/metabolismo , Termogênese , Aumento de Peso
18.
Acta Pharmacol Sin ; 42(9): 1535-1546, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33244163

RESUMO

Vicagrel, a novel irreversible P2Y12 receptor inhibitor, is undergoing phase III trials for the treatment of acute coronary syndromes in China. In this study, we evaluated the pharmacokinetics, mass balance, and metabolism of vicagrel in six healthy male Chinese subjects after a single oral dose of 20 mg [14C]vicagrel (120 µCi). Vicagrel absorption was fast (Tmax = 0.625 h), and the mean t1/2 of vicagrel-related components was ~38.0 h in both plasma and blood. The blood-to-plasma radioactivity AUCinf ratio was 0.55, suggesting preferential distribution of drug-related material in plasma. At 168 h after oral administration, the mean cumulative excreted radioactivity was 96.71% of the dose, including 68.03% in urine and 28.67% in feces. A total of 22 metabolites were identified, and the parent vicagrel was not detected in plasma, urine, or feces. The most important metabolic spot of vicagrel was on the thiophene ring. In plasma pretreated with the derivatization reagent, M9-2, which is a methylated metabolite after thiophene ring opening, was the predominant drug-related component, accounting for 39.43% of the radioactivity in pooled AUC0-8 h plasma. M4, a mono-oxidation metabolite upon ring-opening, was the most abundant metabolite in urine, accounting for 16.25% of the dose, followed by M3-1, accounting for 12.59% of the dose. By comparison, M21 was the major metabolite in feces, accounting for 6.81% of the dose. Overall, renal elimination plays a crucial role in vicagrel disposition, and the thiophene ring is the predominant metabolic site.


Assuntos
Fenilacetatos/metabolismo , Fenilacetatos/farmacocinética , Antagonistas do Receptor Purinérgico P2Y/metabolismo , Antagonistas do Receptor Purinérgico P2Y/farmacocinética , Tiofenos/metabolismo , Tiofenos/farmacocinética , Administração Oral , Adulto , Clopidogrel , Humanos , Masculino , Fenilacetatos/sangue , Fenilacetatos/química , Antagonistas do Receptor Purinérgico P2Y/sangue , Antagonistas do Receptor Purinérgico P2Y/química , Tiofenos/sangue , Tiofenos/química
19.
Artif Organs ; 45(7): 762-769, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33326621

RESUMO

Our aim was to investigate the effect of artificial liver blood purification treatment on the survival of severe/critical patients with coronavirus disease 2019 (COVID-19). A total of 101 severe and critical patients with coronavirus SARS-CoV-2 infection were enrolled in this open, case-control, multicenter, prospective study. According to the patients' and their families' willingness, they were divided into two groups. One was named the treatment group, in which the patients received artificial liver therapy plus comprehensive treatment (n = 50), while the other was named the control group, in which the patients received only comprehensive treatment (n = 51). Clinical data and laboratory examinations, as well as the 28-day mortality rate, were collected and analyzed. Baseline data comparisons on average age, sex, pre-treatment morbidity, initial symptoms, vital signs, pneumonia severity index score, blood routine examination and biochemistry indices etc. showed no difference between the two groups. Cytokine storm was detected, with a significant increase of serum interleukin-6 (IL-6) level. The serum IL-6 level decreased from 119.94 to 20.49 pg/mL in the treatment group and increased from 40.42 to 50.81 pg/mL in the control group (P < .05), indicating that artificial liver therapy significantly decreased serum IL-6. The median duration of viral nucleic acid persistence was 19 days in the treatment group (ranging from 6 to 67 days) and 17 days in the control group (ranging from 3 to 68 days), no significant difference was observed (P = .36). As of 28-day follow-up,17 patients in the treatment group experienced a median weaning time of 24 days, while 11 patients in the control group experienced a median weaning time of 35 days, with no significant difference between the two groups (P = .33). The 28-day mortality rates were 16% (8/50) in the treatment group and 50.98% (26/51) in the control group, with a significant difference (z = 3.70, P < .001). Cytokine storm is a key factor in the intensification of COVID-19 pneumonia. The artificial liver therapy blocks the cytokine storm by clearing inflammatory mediators, thus preventing severe cases from progressing to critically ill stages and markedly reducing short-term mortality.


Assuntos
COVID-19/terapia , Síndrome da Liberação de Citocina/prevenção & controle , Fígado Artificial , Troca Plasmática/instrumentação , Idoso , Biomarcadores/sangue , COVID-19/sangue , COVID-19/mortalidade , COVID-19/virologia , Estudos de Casos e Controles , Síndrome da Liberação de Citocina/sangue , Síndrome da Liberação de Citocina/mortalidade , Síndrome da Liberação de Citocina/virologia , Citocinas/sangue , Feminino , Mortalidade Hospitalar , Interações Hospedeiro-Patógeno , Humanos , Masculino , Pessoa de Meia-Idade , Troca Plasmática/efeitos adversos , Troca Plasmática/mortalidade , Estudos Prospectivos , SARS-CoV-2/patogenicidade , Índice de Gravidade de Doença , Fatores de Tempo , Resultado do Tratamento , Carga Viral
20.
Angew Chem Int Ed Engl ; 60(16): 9032-9037, 2021 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-33529488

RESUMO

Capture and storage of the long-lived 85 Kr is an efficient approach to mitigate the emission of volatile radionuclides from the spent nuclear fuel reprocessing facilities. However, it is challenging to separate krypton (Kr) from xenon (Xe) because of the chemical inertness and similar physical properties. Herein we prepared high-silica CHA zeolite membranes with ultra-high selectivity and irradiation stability for Kr/Xe separation. The suitable aperture size and rigid framework endures the membrane a strong size-exclusion effect. The ultrahigh selectivity of 51-152 together with the Kr permeance of 0.7-1.3×10-8  mol m-2 s-1 Pa-1 of high-silica CHA zeolite membranes far surpass the state-of-the-art polymeric membranes. The membrane is among the most stable polycrystalline membranes for separation of humid Kr/Xe mixtures. Together with the excellent irradiation stability, high-silica CHA zeolite membranes pave the way to separate radioactive Kr from Xe for a notable reduction of the volatile nuclear waste storage volume.

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