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1.
PLoS Biol ; 21(12): e3002249, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38127878

RESUMEN

Despite use of tecovirimat since the beginning of the 2022 outbreak, few data have been published on its antiviral effect in humans. We here predict tecovirimat efficacy using a unique set of data in nonhuman primates (NHPs) and humans. We analyzed tecovirimat antiviral activity on viral kinetics in NHP to characterize its concentration-effect relationship in vivo. Next, we used a pharmacological model developed in healthy volunteers to project its antiviral efficacy in humans. Finally, a viral dynamic model was applied to characterize mpox kinetics in skin lesions from 54 untreated patients, and we used this modeling framework to predict the impact of tecovirimat on viral clearance in skin lesions. At human-recommended doses, tecovirimat could inhibit viral replication from infected cells by more than 90% after 3 to 5 days of drug administration and achieved over 97% efficacy at drug steady state. With an estimated mpox within-host basic reproduction number, R0, equal to 5.6, tecovirimat could therefore shorten the time to viral clearance if given before viral peak. We predicted that initiating treatment at symptom onset, which on average occurred 2 days before viral peak, could reduce the time to viral clearance by about 6 days. Immediate postexposure prophylaxis could not only reduce time to clearance but also lower peak viral load by more than 1.0 log10 copies/mL and shorten the duration of positive viral culture by about 7 to 10 days. These findings support the early administration of tecovirimat against mpox infection, ideally starting from the infection day as a postexposure prophylaxis.


Asunto(s)
Antivirales , Mpox , Animales , Humanos , Antivirales/farmacología , Antivirales/uso terapéutico , Benzamidas , Isoindoles/efectos adversos
2.
Liver Int ; 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38847511

RESUMEN

BACKGROUND AND AIMS: Cyclooxygenase-2 (COX-2) is involved in different liver diseases, but little is known about the significance of COX-2 in cholestatic injury. This study was designed to elucidate the role of COX-2 expression in hepatocytes during the pathogenesis of obstructive cholestasis. METHODS: We used genetically modified mice constitutively expressing human COX-2 in hepatocytes. Transgenic mice (hCOX-2-Tg) and their wild-type (Wt) littermates were either subjected to a mid-abdominal laparotomy or common bile duct ligation (BDL) for 2 or 5 days. Then, we explored the mechanisms underlying the role of COX-2 and its derived prostaglandins in liver function, and the synthesis and excretion of bile acids (BA) in response to cholestatic liver injury. RESULTS: After BDL, hCOX-2-Tg mice showed lower grades of hepatic necrosis and inflammation than Wt mice, in part by a reduced hepatic neutrophil recruitment associated with lower mRNA levels of pro-inflammatory cytokines. Furthermore, hCOX-2-Tg mice displayed a differential metabolic pattern of BA synthesis that led to an improved clearance after BDL-induced accumulation. In addition, an enhanced response to the BDL-induced oxidative stress and hepatic apoptosis was observed. In vitro experiments using hepatic cells that stably express hCOX-2 confirmed the cytoprotective role of prostaglandin E2 against BA toxicity. CONCLUSIONS: Taken together, our data indicate that constitutive expression of COX-2 in hepatocytes ameliorates cholestatic liver injury in mice by reducing inflammation and cell damage and by modulating BA metabolism, pointing to a role for COX-2 as a defensive response against cholestasis-derived BA accumulation and injury.

3.
Clin Infect Dis ; 76(7): 1311-1314, 2023 04 03.
Artículo en Inglés | MEDLINE | ID: mdl-36370091

RESUMEN

We evaluated the accuracy of patient-collected skin lesions, oropharyngeal, and rectal swabs among 50 individuals enrolled in a study of mpox viral dynamics. We found that the performance of self-collected samples was similar to that of physician-collected samples, suggesting that self-sampling is a reliable strategy for diagnosing mpox.


Asunto(s)
Mpox , Humanos , Femenino , Orofaringe , Frotis Vaginal
4.
Lancet ; 400(10353): 661-669, 2022 08 27.
Artículo en Inglés | MEDLINE | ID: mdl-35952705

RESUMEN

BACKGROUND: In May, 2022, several European countries reported autochthonous cases of monkeypox, which rapidly spread globally. Early reports suggest atypical presentations. We aimed to investigate clinical and virological characteristics of cases of human monkeypox in Spain. METHODS: This multicentre, prospective, observational cohort study was done in three sexual health clinics in Madrid and Barcelona, Spain. We enrolled all consecutive patients with laboratory-confirmed monkeypox from May 11 to June 29, 2022. Participants were offered lesion, anal, and oropharynx swabs for PCR testing. Participant data were collected by means of interviews conducted by dermatologists or specialists in sexually transmitted infections and were recorded using a standard case report form. Outcomes assessed in all participants with a confirmed diagnosis were demographics, smallpox vaccination, HIV status, exposure to someone with monkeypox, travel, mass gathering attendance, risk factors for sexually transmitted infections, sexual behaviour, signs and symptoms on first presentation, virological results at multiple body sites, co-infection with other sexually transmitted pathogens, and clinical outcomes 14 days after the initial presentation. Clinical outcomes were followed up until July 13, 2022. FINDINGS: 181 patients had a confirmed monkeypox diagnosis and were enrolled in the study. 166 (92%) identified as gay men, bisexual men, or other men who have sex with men (MSM) and 15 (8%) identified as heterosexual men or heterosexual women. Median age was 37·0 years (IQR 31·0-42·0). 32 (18%) patients reported previous smallpox vaccination, 72 (40%) were HIV-positive, eight (11%) had a CD4 cell count less than 500 cells per µL, and 31 (17%) were diagnosed with a concurrent sexually transmitted infection. Median incubation was 7·0 days (IQR 5·0-10·0). All participants presented with skin lesions; 141 (78%) participants had lesions in the anogenital region, and 78 (43%) in the oral and perioral region. 70 (39%) participants had complications requiring treatment: 45 (25%) had a proctitis, 19 (10%) had tonsillitis, 15 (8%) had penile oedema, six (3%) an abscess, and eight (4%) had an exanthem. Three (2%) patients required hospital admission. 178 (99%) of 180 swabs from skin lesions collected tested positive, as did 82 (70%) of 117 throat swabs. Viral load was higher in lesion swabs than in pharyngeal specimens (mean cycle threshold value 23 [SD 4] vs 32 [6], absolute difference 9 [95% CI 8-10]; p<0·0001). 108 (65%) of 166 MSM reported anal-receptive sex. MSM who engaged in anal-receptive sex presented with proctitis (41 [38%] of 108 vs four [7%] of 58, absolute difference 31% [95% CI 19-44]; p<0·0001) and systemic symptoms before the rash (67 [62%] vs 16 [28%], absolute difference 34% [28-62]; p<0·0001) more frequently than MSM who did not engage in anal-receptive sex. 18 (95%) of 19 participants with tonsillitis reported practising oral-receptive sex. The median time from onset of lesions to formation of a dry crust was 10 days (IQR 7-13). INTERPRETATION: In our cohort, monkeypox caused genital, perianal, and oral lesions and complications including proctitis and tonsillitis. Because of the variability of presentations, clinicians should have a low threshold for suspicion of monkeypox. Lesion swabs showed the highest viral loads, which, combined with the history of sexual exposure and the distribution of lesions, suggests close contact is probably the dominant transmission route in the current outbreak. FUNDING: None.


Asunto(s)
Infecciones por VIH , Mpox , Proctitis , Minorías Sexuales y de Género , Enfermedades de Transmisión Sexual , Viruela , Tonsilitis , Adulto , Femenino , Homosexualidad Masculina , Humanos , Masculino , Monkeypox virus , Estudios Prospectivos , Conducta Sexual , España
5.
J Med Virol ; 95(11): e29240, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37971716

RESUMEN

To evaluate molecular assays for Mpox diagnosis available in various clinical microbiology services in Spain through a quality control (QC) approach. A total of 14 centers from across Spain participated in the study. The Reference Laboratory dispatched eight serum samples and eight nucleic acid extracts to each participating center. Some samples were spiked with Mpox or Vaccinia virus to mimic positive samples for Mpox or other orthopox viruses. Participating centers provided information on the results obtained, as well as the laboratory methods used. Among the 14 participating centers seven different commercial assays were employed, with the most commonly used kit being LightMix Modular Orthopox/Monkeypox (Mpox) Virus (Roche®). Of the 12 centers conducting Mpox determinations, concordance ranged from 62.5% (n = 1) to 100% (n = 11) for eluates and from 75.0% (n = 1) to 100% (n = 10) for serum. Among the 10 centers performing Orthopoxvirus determinations, a 100% concordance was observed for eluates, while for serum, concordance ranged from 87.5% (n = 6) to 100% (n = 4). Repeatedly, 6 different centers reported a false negative in serum samples for Orthopoxvirus diagnosis, particularly in a sample with borderline Ct = 39. Conversely, one center, using the TaqMan™ Mpox Virus Microbe Detection Assay (Thermo Fisher), reported false positives in Mpox diagnosis for samples spiked with vaccinia virus due to cross-reactions. We observed a positive correlation of various diagnostic assays for Mpox used by the participating centers with the reference values. Our results highlight the significance of standardization, validation, and ongoing QC in the microbiological diagnosis of infectious diseases, which might be particularly relevant for emerging viruses.


Asunto(s)
Mpox , Orthopoxvirus , Humanos , Monkeypox virus/genética , Mpox/diagnóstico , Reacción en Cadena de la Polimerasa , Control de Calidad , Virus Vaccinia/genética , ADN
6.
Liver Int ; 43(8): 1714-1728, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37057737

RESUMEN

BACKGROUND AND AIMS: The molecular mechanisms driving non-alcoholic fatty liver disease (NAFLD) are poorly understood; however, microRNAs might play a key role in these processes. We hypothesize that let-7d-5p could contribute to the pathophysiology of NAFLD and serve as a potential diagnostic biomarker. METHODS: We evaluated let-7d-5p levels and its targets in liver biopsies from a cross-sectional study including patients with NAFLD and healthy donors, and from a mouse model of NAFLD. Moreover, the induction of let-7d-5p expression by fatty acids was evaluated in vitro. Further, we overexpressed let-7d-5p in vitro to corroborate the results observed in vivo. Circulating let-7d-5p and its potential as a NAFLD biomarker was determined in isolated extracellular vesicles from human plasma by RT-qPCR. RESULTS: Our results demonstrate that hepatic let-7d-5p was significantly up-regulated in patients with steatosis, and this increase correlated with obesity and a decreased expression of AKT serine/threonine kinase (AKT), insulin-like growth factor 1 (IGF1), IGF-I receptor (IGF1R) and insulin receptor (INSR). These alterations were corroborated in a NAFLD mouse model. In vitro, fatty acids increased let-7d-5p expression, and its overexpression decreased AKT, IGF-IR and IR protein expression. Furthermore, let-7d-5p hindered AKT phosphorylation in vitro after insulin stimulation. Finally, circulating let-7d-5p significantly decreased in steatosis patients and receiver operating characteristic (ROC) analyses confirmed its utility as a diagnostic biomarker. CONCLUSIONS: Our results highlight the emerging role of let-7d-5p as a potential therapeutic target for NAFLD since its overexpression impairs hepatic insulin signalling, and also, as a novel non-invasive biomarker for NAFLD diagnosis.


Asunto(s)
Resistencia a la Insulina , MicroARNs , Enfermedad del Hígado Graso no Alcohólico , Animales , Humanos , Ratones , Biomarcadores , Estudios Transversales , Ácidos Grasos , Insulina , MicroARNs/genética , MicroARNs/metabolismo , Enfermedad del Hígado Graso no Alcohólico/patología , Proteínas Proto-Oncogénicas c-akt
7.
J Hepatol ; 76(1): 11-24, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34555423

RESUMEN

BACKGROUND & AIMS: Autophagy-related gene 3 (ATG3) is an enzyme mainly known for its actions in the LC3 lipidation process, which is essential for autophagy. Whether ATG3 plays a role in lipid metabolism or contributes to non-alcoholic fatty liver disease (NAFLD) remains unknown. METHODS: By performing proteomic analysis on livers from mice with genetic manipulation of hepatic p63, a regulator of fatty acid metabolism, we identified ATG3 as a new target downstream of p63. ATG3 was evaluated in liver samples from patients with NAFLD. Further, genetic manipulation of ATG3 was performed in human hepatocyte cell lines, primary hepatocytes and in the livers of mice. RESULTS: ATG3 expression is induced in the liver of animal models and patients with NAFLD (both steatosis and non-alcoholic steatohepatitis) compared with those without liver disease. Moreover, genetic knockdown of ATG3 in mice and human hepatocytes ameliorates p63- and diet-induced steatosis, while its overexpression increases the lipid load in hepatocytes. The inhibition of hepatic ATG3 improves fatty acid metabolism by reducing c-Jun N-terminal protein kinase 1 (JNK1), which increases sirtuin 1 (SIRT1), carnitine palmitoyltransferase 1a (CPT1a), and mitochondrial function. Hepatic knockdown of SIRT1 and CPT1a blunts the effects of ATG3 on mitochondrial activity. Unexpectedly, these effects are independent of an autophagic action. CONCLUSIONS: Collectively, these findings indicate that ATG3 is a novel protein implicated in the development of steatosis. LAY SUMMARY: We show that autophagy-related gene 3 (ATG3) contributes to the progression of non-alcoholic fatty liver disease in humans and mice. Hepatic knockdown of ATG3 ameliorates the development of NAFLD by stimulating mitochondrial function. Thus, ATG3 is an important factor implicated in steatosis.


Asunto(s)
Proteínas Relacionadas con la Autofagia/antagonistas & inhibidores , Hígado Graso/prevención & control , Mitocondrias Hepáticas/metabolismo , Enzimas Ubiquitina-Conjugadoras/antagonistas & inhibidores , Animales , Proteínas Relacionadas con la Autofagia/farmacología , Modelos Animales de Enfermedad , Hígado Graso/fisiopatología , Metabolismo de los Lípidos/genética , Ratones , Mitocondrias Hepáticas/fisiología , Proteómica/métodos , Enzimas Ubiquitina-Conjugadoras/farmacología
8.
Hepatology ; 73(2): 606-624, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-32329085

RESUMEN

BACKGROUND AND AIMS: G protein-coupled receptor (GPR) 55 is a putative cannabinoid receptor, and l-α-lysophosphatidylinositol (LPI) is its only known endogenous ligand. Although GPR55 has been linked to energy homeostasis in different organs, its specific role in lipid metabolism in the liver and its contribution to the pathophysiology of nonalcoholic fatty liver disease (NAFLD) remains unknown. APPROACH AND RESULTS: We measured (1) GPR55 expression in the liver of patients with NAFLD compared with individuals without obesity and without liver disease, as well as animal models with steatosis and nonalcoholic steatohepatitis (NASH), and (2) the effects of LPI and genetic disruption of GPR55 in mice, human hepatocytes, and human hepatic stellate cells. Notably, we found that circulating LPI and liver expression of GPR55 were up-regulated in patients with NASH. LPI induced adenosine monophosphate-activated protein kinase activation of acetyl-coenzyme A carboxylase (ACC) and increased lipid content in human hepatocytes and in the liver of treated mice by inducing de novo lipogenesis and decreasing ß-oxidation. The inhibition of GPR55 and ACCα blocked the effects of LPI, and the in vivo knockdown of GPR55 was sufficient to improve liver damage in mice fed a high-fat diet and in mice fed a methionine-choline-deficient diet. Finally, LPI promoted the initiation of hepatic stellate cell activation by stimulating GPR55 and activation of ACC. CONCLUSIONS: The LPI/GPR55 system plays a role in the development of NAFLD and NASH by activating ACC.


Asunto(s)
Lisofosfolípidos/metabolismo , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Obesidad/complicaciones , Receptores de Cannabinoides/metabolismo , Acetil-CoA Carboxilasa/antagonistas & inhibidores , Acetil-CoA Carboxilasa/metabolismo , Adulto , Anciano , Animales , Biopsia , Agonistas de Receptores de Cannabinoides/farmacología , Línea Celular , Estudios de Cohortes , Dieta Alta en Grasa/efectos adversos , Modelos Animales de Enfermedad , Femenino , Técnicas de Silenciamiento del Gen , Células Estrelladas Hepáticas , Hepatocitos , Humanos , Lipogénesis/efectos de los fármacos , Hígado/patología , Lisofosfolípidos/sangre , Masculino , Ratones , Persona de Mediana Edad , Enfermedad del Hígado Graso no Alcohólico/sangre , Enfermedad del Hígado Graso no Alcohólico/etiología , Enfermedad del Hígado Graso no Alcohólico/patología , Obesidad/sangre , Obesidad/metabolismo , Receptores de Cannabinoides/genética , Regulación hacia Arriba
9.
J Exp Bot ; 73(13): 4562-4575, 2022 07 16.
Artículo en Inglés | MEDLINE | ID: mdl-35298628

RESUMEN

The data available so far indicate that the photosynthetic and relative growth rates of bryophytes are 10% of those reported for tracheophytes. By examining the existing literature and reanalysing data published in over 100 studies, this review examines the ecophysiological, biochemical, and structural reasons behind this phenomenon. The limiting Rubisco content and surface for gas exchange are the internal factors that can explain the low photosynthetic and growth rates of bryophytes. The role of the thicker cell walls of bryophytes in limiting CO2 diffusion is unclear, due to the current uncertainties regarding their porosity and permeability to CO2. From this review, it is also evident that, despite bryophytes having low photosynthetic rates, their positive carbon balance is tightly related to their capacity to deal with extreme conditions. Contributing factors include their capacity to deal with large daily temperature oscillations, and their capacity to delay the cessation of photosynthesis under water deficit (or to tolerate desiccation in extreme situations). Although further studies on bryophytes are needed before more solid conclusions can be drawn, it seems that their success relies on their remarkable tolerance to a highly variable environment, possibly at the expense of their maximum photosynthetic rate.


Asunto(s)
Briófitas , Carbono , Briófitas/metabolismo , Dióxido de Carbono , Fotosíntesis/fisiología , Hojas de la Planta/metabolismo , Ribulosa-Bifosfato Carboxilasa/metabolismo
10.
Photosynth Res ; 149(1-2): 135-153, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33033976

RESUMEN

In Antarctica, multiple stresses (low temperatures, drought and excessive irradiance) hamper photosynthesis even in summer. We hypothesize that controlled inactivation of PSII reaction centres, a mechanism widely studied by pioneer work of Fred Chow and co-workers, may effectively guarantee functional photosynthesis under these conditions. Thus, we analysed the energy partitioning through photosystems in response to temperature in 15 bryophyte species presenting different worldwide distributions but all growing in Livingston Island, under controlled and field conditions. We additionally tested their tolerance to desiccation and freezing and compared those with their capability for sexual reproduction in Antarctica (as a proxy to overall fitness). Under field conditions, when irradiance rules air temperature by the warming of shoots (up to 20 °C under sunny days), a predominance of sustained photoinhibition beyond dynamic heat dissipation was observed at low temperatures. Antarctic endemic and polar species showed the largest increases of photoinhibition at low temperatures. On the contrary, the variation of thermal dissipation with temperature was not linked to species distribution. Instead, maximum non-photochemical quenching at 20 °C was related (strongly and positively) with desiccation tolerance, which also correlated with fertility in Antarctica, but not with freezing tolerance. Although all the analysed species tolerated - 20 °C when dry, the tolerance to freezing in hydrated state ranged from the exceptional ability of Schistidium rivulare (that survived for 14 months at - 80 °C) to the susceptibility of Bryum pseudotriquetrum (that died after 1 day at - 20 °C unless being desiccated before freezing).


Asunto(s)
Adaptación Fisiológica , Briófitas/fisiología , Frío/efectos adversos , Deshidratación , Congelación/efectos adversos , Fotosíntesis/fisiología , Luz Solar/efectos adversos , Regiones Antárticas
11.
Liver Int ; 41(9): 2076-2086, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33896100

RESUMEN

BACKGROUND AND AIM: Histological score systems may not fully capture the essential nonalcoholic steatohepatitis (NASH) features, which is one of the leading causes of screening failure in clinical trials. We assessed the NASH distribution and its components across the fibrosis stages and their impact on the prognosis and their relationship with the concept of metabolic-associated fatty liver disease (MAFLD). METHODS: Spanish multicenter study including 1893 biopsy-proven nonalcoholic fatty liver disease (NAFLD) patients from HEPAmet registry. NASH was diagnosed by NAS score ≥4 (including steatosis, ballooning and lobular inflammation) and fibrosis by Kleiner score. The presence of MAFLD was determined. Progression to cirrhosis, first episode of decompensated cirrhosis and death were collected during the follow-up (4.7 ± 3.8 years). RESULTS: Fibrosis was F0 34.3% (649/1893), F1 27% (511/1893), F2 16.5% (312/1893), F3 15% (284/1893) and F4 7.2% (137/1893). NASH diagnosis 51.9% (982/1893), and its individual components (severe steatosis, ballooning and lobular inflammation), increased from F0 (33.6%) to F2 (68.6%), and decreased significantly in F4 patients (51.8%) (P = .0001). More than 70% of non-NASH patients showed some inflammatory activity (ballooning or lobular inflammation), showing a similar MAFLD rate than NASH (96.2% [945/982] vs. 95.2% [535/562]) and significantly higher than nonalcoholic fatty liver (NAFL) subjects (89.1% [311/349]) (P < .0001). Progression to cirrhosis was similar between NASH (9.5% [51/539]) and indeterminate NASH (7.9% [25/316]), and higher than steatosis (5% [14/263]) (logRank 8.417; P = .015). Death and decompensated cirrhosis were similar between these. CONCLUSIONS: The prevalence of steatohepatitis decreased in advanced liver disease. However, most of these patients showed some inflammatory activity histologically and had metabolic disturbances. These findings should be considered in clinical trials whose main aim is to prevent cirrhosis progression and complications, liver transplant and death.


Asunto(s)
Enfermedad del Hígado Graso no Alcohólico , Biopsia , Humanos , Hígado/patología , Cirrosis Hepática/patología , Estudios Longitudinales , Enfermedad del Hígado Graso no Alcohólico/epidemiología , Enfermedad del Hígado Graso no Alcohólico/patología
12.
Liver Int ; 40(10): 2553-2567, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32432822

RESUMEN

BACKGROUND & AIMS: Molecular mechanisms by which hypoxia might contribute to hepatosteatosis, the earliest stage in non-alcoholic fatty liver disease (NAFLD) pathogenesis, remain still to be elucidated. We aimed to assess the impact of hypoxia-inducible factor 2α (HIF2α) on the fatty acid translocase CD36 expression and function in vivo and in vitro. METHODS: CD36 expression and intracellular lipid content were determined in hypoxic hepatocytes, and in hypoxic CD36- or HIF2α -silenced human liver cells. Histological analysis, and HIF2α and CD36 expression were evaluated in livers from animals in which von Hippel-Lindau (Vhl) gene is inactivated (Vhlf/f -deficient mice), or both Vhl and Hif2a are simultaneously inactivated (Vhlf/f Hif2α/f -deficient mice), and from 33 biopsy-proven NAFLD patients and 18 subjects with histologically normal liver. RESULTS: In hypoxic hepatocytes, CD36 expression and intracellular lipid content were augmented. Noteworthy, CD36 knockdown significantly reduced lipid accumulation, and HIF2A gene silencing markedly reverted both hypoxia-induced events in hypoxic liver cells. Moreover livers from Vhlf/f -deficient mice showed histologic characteristics of non-alcoholic steatohepatitis (NASH) and increased CD36 mRNA and protein amounts, whereas both significantly decreased and NASH features markedly ameliorated in Vhlf/f Hif2αf/f -deficient mice. In addition, both HIF2α and CD36 were significantly overexpressed within the liver of NAFLD patients and, interestingly, a significant positive correlation between hepatic transcript levels of CD36 and erythropoietin (EPO), a HIF2α -dependent gene target, was observed in NAFLD patients. CONCLUSIONS: This study provides evidence that HIF2α drives lipid accumulation in human hepatocytes by upregulating CD36 expression and function, and could contribute to hepatosteatosis setup.


Asunto(s)
Enfermedad del Hígado Graso no Alcohólico , Animales , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico , Antígenos CD36/genética , Ácidos Grasos , Humanos , Hipoxia , Hígado , Ratones
13.
Liver Int ; 40(9): 2182-2193, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32559006

RESUMEN

BACKGROUND & AIMS: Low-grade systemic inflammation is a crucial landmark in NAFLD favouring disease progression and comorbidities. We evaluated the input of circulating bacterial antigens on systemic markers of inflammation in NAFLD patients. PATIENTS & METHODS: Multicenter cross-sectional study including consecutive patients with biopsy-proven NAFLD. Demographic, metabolic and fibrosis-related variables were collected. Circulating bacterial antigens were quantified in blood. Toll-like receptor SNPs were genotyped. Serum cytokine levels were evaluated. Peripheral blood mononuclear cell response to bacterial antigens was evaluated in vitro. RESULTS: Three hundred and fifteen patients from five Spanish hospitals were distributed by BMI. At least, one bacterial antigenic type was found in 66 patients with BMI < 30 (63.4%) and 163 patients with BMI > 30 (77.3%) (P = .014). HOMA-IR was significantly higher in the presence of circulating antigens among patients with BMI < 30. NASH and significant fibrosis in non-obese patients were more frequent in the presence of at least two circulating antigenic types. Allelic frequencies of TLR variants were similar to controls and did not affect clinical or laboratory parameters. Pro-inflammatory cytokines were significantly increased in patients with bacterial antigens, regardless of BMI. TLR gene and protein expression levels were significantly increased in PBMCs from patients with bacterial antigens. Antigen concentrations independently influenced TNF-α and IL-6, in both BMI subgroups of patients. Age independently influenced TNF-α and IL-6 in non-obese patients, and TNF-α in obese patients. CONCLUSION: Serum circulating bacterial antigens as well as age were BMI-independent factors related to increased systemic inflammation in NAFLD and provides insight on the multifaceted sources of inflammation in these patients.


Asunto(s)
Enfermedad del Hígado Graso no Alcohólico , Antígenos Bacterianos , Índice de Masa Corporal , Estudios Transversales , Humanos , Inflamación , Leucocitos Mononucleares
14.
Physiol Plant ; 169(2): 228-243, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32012285

RESUMEN

High-mountain-ecosystems in the Mediterranean-type climate are exceptional because of their outstanding biodiversity but also because of their characteristic drought stress in summer. Still, plant functioning in these habitats has been largely understudied. Here, morphological, photochemical, and biochemical traits were seasonally assessed in six shrubs characterized by contrasting morphological traits, in the Teide mountain in the Canary Islands. Two adjacent populations, the first located in an open site and the second in the understorey of Pinus canariensis treeline forest, were evaluated. We aimed at disentangling (1) the role of morphological and biochemical photoprotective strategies and of their seasonal plasticity to cope with changing environmental conditions in this semiarid ecosystem, (2) how the interspecific differences in biochemical photoprotection are related to leaf morphology and phenology and (3) how living in the understory of the treeline may affect those responses. Our results indicate that both morphological and biochemical traits (particularly leaf habit, morphology and carotenoids from the ß-branch) play an intricate role in photoprotection, and that a high interspecific variability exists. According to the down-regulation of photochemical activity and the upregulation of photoprotective molecules, species could be grouped into three types: (1) those more responsive to summer stress (e.g. Descurainia bourgeauana); (2) those more responsive to winter stress (e.g. Pterocephalus lasiospermus, Scrophularia glabrata and Adenocarpus viscosus); and (3) those showing rather constant behavior across seasons (e.g. Spartocytisus supranubius and Erysimum scoparium). In all the species, plants in the open site showed a marked seasonal physiological response in most of the studied parameters. Pinus canariensis canopy buffers environmental abiotic constrains. On a global change scenario, and provided further functional studies are needed, our results pinpoints heterogeneity in the sensitivity of these species against for instance late-frost or summer-heat/drought events, which could easily shift current species distribution in the coming years.


Asunto(s)
Sequías , Bosques , Pinus/crecimiento & desarrollo , Hojas de la Planta/anatomía & histología , Estaciones del Año , España
15.
Clin Infect Dis ; 68(5): 834-843, 2019 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-29982484

RESUMEN

BACKGROUND: Epstein-Barr virus (EBV) has been implicated in lymphomagenesis and can be found infecting tumor cells and in plasma at lymphoma diagnosis, especially in human immunodeficiency virus (HIV)-infected patients. Our aim was to evaluate the usefulness of plasma EBV load as biomarker and prognostic factor in HIV-positive patients with lymphomas. METHODS: EBV loads were measured by polymerase chain reaction in plasma samples of 81 HIV-positive patients' lymphomas at different moments: within 1 year before lymphoma diagnosis, at diagnosis, and at complete response (CR). Control samples included HIV-negative patients with lymphomas and HIV-positive patients without neoplasia or opportunistic infections. RESULTS: HIV-positive patients with lymphomas had more frequently-detectable EBV load at lymphoma diagnosis (53%) than either HIV-negative patients with the same lymphoma type (16%; P < .001) or HIV-positive individuals without neoplasia or opportunistic infection (1.2%; P < .001). HIV-positive lymphoma patients with detectable EBV load in plasma at lymphoma diagnosis had statistically significant decrease of EBV load at CR. High EBV load (>5000 copies/mL) at lymphoma diagnosis was an independent negative prognostic factor for overall survival and progression-free survival in HIV-positive patients with lymphomas. Detectable plasma EBV loads identified HIV-positive subjects that would eventually develop lymphoma (area under the curve, 82%; 95% CI: 0.67-0.96). CONCLUSIONS: Plasma EBV load can be used as a biomarker and as a prognostic factor in HIV-positive patients with lymphomas. The presence of the EBV load in the plasma of an HIV-positive patient can be an early predictor of lymphoma development.


Asunto(s)
Infecciones por VIH/complicaciones , Herpesvirus Humano 4 , Linfoma Relacionado con SIDA/virología , Carga Viral , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores/sangre , Estudios de Casos y Controles , Femenino , Infecciones por VIH/sangre , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Adulto Joven
16.
Am J Pathol ; 188(12): 2800-2810, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30248338

RESUMEN

Hepatic vitamin D receptor (VDR) expression is increased in patients with nonalcoholic fatty liver (NAFL) and is required for liver steatosis in an NAFL mouse model. However, how hepatocyte VDR is involved in setting up steatosis remains unclear. The authors transduced human hepatocyte-derived cells with an adenoviral vector encoding human VDR and found that angiopoietin-like protein 8 (ANGPTL8) expression was increased upon VDR activation by vitamin D or lithocholic acid. The mRNA levels of hepatic VDR- and vitamin D-related genes [cytochrome P450 (CYP) 2R1, CYP27A1, and CYP3A4] were higher in NAFL patients compared with normal liver subjects. Noteworthy, hepatic ANGPTL8 mRNA and protein levels were elevated in NAFL patients, and its mRNA correlated with VDR mRNA and with the steatosis grade. Moreover, increases in serum conjugated bile acids, including the VDR agonist glycine-lithocholic acid, were observed in NAFL patients. Additionally, free fatty acids and insulin were able to up-regulate both VDR and ANGPTL8 mRNA in human hepatocytes, whereas ANGPTL8 gene knockdown attenuated free fatty acids-induced triglyceride accumulation in these cells. In conclusion, activated VDR up-regulates ANGPTL8 expression, contributing to triglyceride accumulation in human hepatocytes. Moreover, hepatic ANGPTL8 mRNA positively correlates with VDR mRNA content and the grade of steatosis in NAFL patients, suggesting that this novel pathway may play a key role in the pathogenesis of hepatosteatosis.


Asunto(s)
Proteínas Similares a la Angiopoyetina/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Hepatocitos/patología , Enfermedad del Hígado Graso no Alcohólico/patología , Hormonas Peptídicas/metabolismo , Receptores de Calcitriol/metabolismo , Adulto , Proteína 8 Similar a la Angiopoyetina , Proteínas Similares a la Angiopoyetina/genética , Estudios de Casos y Controles , Células Cultivadas , Ácidos Grasos no Esterificados/farmacología , Femenino , Hepatocitos/efectos de los fármacos , Hepatocitos/metabolismo , Humanos , Insulina/farmacología , Masculino , Persona de Mediana Edad , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológico , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Hormonas Peptídicas/genética , Receptores de Calcitriol/genética , Triglicéridos/metabolismo
17.
Euro Surveill ; 24(7)2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30782267

RESUMEN

IntroductionEnterovirus A71 (EV-A71) is an emerging pathogen that causes a wide range of disorders including severe neurological manifestations. In the past 20 years, this virus has been associated with large outbreaks of hand, foot and mouth disease with neurological complications in the Asia-Pacific region, while in Europe mainly sporadic cases have been reported. In spring 2016, however, an EV-A71 outbreak associated with severe neurological cases was reported in Catalonia and spread further to other Spanish regions.AimOur objective was to investigate the epidemiology and clinical characteristics of the outbreak.MethodsWe carried out a retrospective study which included 233 EV-A71-positive samples collected during 2016 from hospitalised patients. We analysed the clinical manifestations associated with EV-A71 infections and performed phylogenetic analyses of the 3'-VP1 and 3Dpol regions from all Spanish strains and a set of EV-A71 from other countries.ResultsMost EV-A71 infections were reported in children (mean age: 2.6 years) and the highest incidence was between May and July 2016 (83%). Most isolates (218/233) were classified as subgenogroup C1 and 217 of them were grouped in one cluster phylogenetically related to a new recombinant variant strain associated with severe neurological diseases in Germany and France in 2015 and 2016. Moreover, we found a clear association of EV-A71-C1 infection with severe neurological disorders, brainstem encephalitis being the most commonly reported.ConclusionAn emerging recombinant variant of EV-A71-C1 was responsible for the large outbreak in 2016 in Spain that was associated with many severe neurological cases.


Asunto(s)
Brotes de Enfermedades/estadística & datos numéricos , Enterovirus Humano A/genética , Enterovirus Humano A/aislamiento & purificación , Infecciones por Enterovirus/epidemiología , Enfermedades del Sistema Nervioso/diagnóstico , Enfermedades del Sistema Nervioso/virología , ARN Viral/genética , Infecciones del Sistema Respiratorio/virología , Antígenos Virales , Preescolar , Enterovirus Humano A/clasificación , Infecciones por Enterovirus/diagnóstico , Infecciones por Enterovirus/virología , Hospitalización , Humanos , Lactante , Epidemiología Molecular , Enfermedades del Sistema Nervioso/líquido cefalorraquídeo , Enfermedades del Sistema Nervioso/epidemiología , Filogenia , Filogeografía , ARN Viral/aislamiento & purificación , Infecciones del Sistema Respiratorio/epidemiología , Estudios Retrospectivos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Análisis de Secuencia de ADN , Análisis de Secuencia de ARN , España/epidemiología
18.
J Antimicrob Chemother ; 73(7): 1940-1948, 2018 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-29635527

RESUMEN

Background: Monotherapy with ritonavir-boosted PIs (PI/r) has been used to simplify treatment of HIV-1-infected patients. In previous studies raltegravir intensification evidenced ongoing viral replication and reduced T cell activation, preferentially in subjects receiving PI-based triple ART. However, data about low-level viral replication and its consequences in patients receiving PI/r monotherapy are scarce. Methods: We evaluated the impact of 24 weeks of intensification with raltegravir on markers of viral persistence, cellular immune activation and inflammation biomarkers in 33 patients receiving maintenance PI/r monotherapy with darunavir or lopinavir boosted with ritonavir. ClinicalTrials.gov identifier: NCT01480713. Results: The addition of raltegravir to PI/r monotherapy resulted in a transient increase in 2-LTR (long-terminal repeat) circles in a significant proportion of participants, along with decreases in CD8+ T cell activation levels and a temporary increase in the expression of the exhaustion marker CTLA-4 in peripheral T lymphocytes. Intensification with raltegravir also reduced the number of samples with intermediate levels of residual viraemia (10-60 HIV-1 RNA copies/mL) compared with samples taken during PI/r monotherapy. However, there were no changes in cell-associated HIV-1 DNA in peripheral CD4+ T cells or soluble inflammatory biomarkers (CD14, IP-10, IL-6, C-reactive protein and D-dimer). Conclusions: Intensification of PI/r monotherapy with raltegravir revealed persistent low-level viral replication and reduced residual viraemia in some patients during long-term PI/r monotherapy. The concomitant change in T cell phenotype suggests an association between active viral production and T cell activation. These results contribute to understanding the lower efficacy rates of PI/r monotherapies compared with triple therapies in clinical trials.


Asunto(s)
Infecciones por VIH/tratamiento farmacológico , Inhibidores de la Proteasa del VIH/uso terapéutico , VIH-1/efectos de los fármacos , Raltegravir Potásico/uso terapéutico , Replicación Viral/efectos de los fármacos , Adulto , Terapia Antirretroviral Altamente Activa , Darunavir/uso terapéutico , Infecciones por VIH/inmunología , VIH-1/fisiología , Humanos , Inmunidad Celular , Inflamación , Lopinavir/uso terapéutico , Activación de Linfocitos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Prueba de Estudio Conceptual , ARN Viral , Viremia/tratamiento farmacológico
19.
Hepatology ; 65(3): 950-968, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-27880981

RESUMEN

Because nonalcoholic steatohepatitis (NASH) is associated with impaired liver regeneration, we investigated the effects of G49, a dual glucagon-like peptide-1/glucagon receptor agonist, on NASH and hepatic regeneration. C57Bl/6 mice fed chow or a methionine and choline-deficient (MCD) diet for 1 week were divided into 4 groups: control (chow diet), MCD diet, chow diet plus G49, and M+G49 (MCD diet plus G49). Mice fed a high-fat diet (HFD) for 10 weeks were divided into groups: HFD and H+G49 (HFD plus G49). Following 2 (MCD groups) or 3 (HFD groups) weeks of treatment with G49, partial hepatectomy (PH) was performed, and all mice were maintained on the same treatment schedule for 2 additional weeks. Analysis of liver function, hepatic regeneration, and comprehensive genomic and metabolic profiling were conducted. NASH was ameliorated in the M+G49 group, manifested by reduced inflammation, steatosis, oxidative stress, and apoptosis and increased mitochondrial biogenesis. G49 treatment was also associated with replenishment of intrahepatic glucose due to enhanced gluconeogenesis and reduced glucose use through the pentose phosphate cycle and oxidative metabolism. Following PH, G49 treatment increased survival, restored the cytokine-mediated priming phase, and enhanced the proliferative capacity and hepatic regeneration ratio in mice on the MCD diet. NASH markers remained decreased in M+G49 mice after PH, and glucose use was shifted to the pentose phosphate cycle and oxidative metabolism. G49 administered immediately after PH was also effective at alleviating the pathological changes induced by the MCD diet. Benefits in terms of liver regeneration were also found in mice fed HFD and treated with G49. CONCLUSION: Dual-acting glucagon-like peptide-1/glucagon receptor agonists such as G49 represent a novel therapeutic approach for patients with NASH and particularly those requiring PH. (Hepatology 2017;65:950-968).


Asunto(s)
Péptido 1 Similar al Glucagón/antagonistas & inhibidores , Regeneración Hepática/efectos de los fármacos , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológico , Receptores de Glucagón/antagonistas & inhibidores , Animales , Biopsia con Aguja , Modelos Animales de Enfermedad , Péptido 1 Similar al Glucagón/farmacología , Humanos , Inmunohistoquímica , Peroxidación de Lípido , Regeneración Hepática/fisiología , Masculino , Ratones , Ratones Endogámicos C57BL , Enfermedad del Hígado Graso no Alcohólico/patología , Estrés Oxidativo , Distribución Aleatoria , Receptores de Glucagón/administración & dosificación , Resultado del Tratamiento
20.
Hepatology ; 63(2): 604-19, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26313466

RESUMEN

UNLABELLED: Different data support a role for the epidermal growth factor receptor (EGFR) pathway during liver regeneration and hepatocarcinogenesis. However, important issues, such as the precise mechanisms mediating its actions and the unique versus redundant functions, have not been fully defined. Here, we present a novel transgenic mouse model expressing a hepatocyte-specific truncated form of human EGFR, which acts as negative dominant mutant (ΔEGFR) and allows definition of its tyrosine kinase-dependent functions. Results indicate a critical role for EGFR catalytic activity during the early stages of liver regeneration. Thus, after two-thirds partial hepatectomy, ΔEGFR livers displayed lower and delayed proliferation and lower activation of proliferative signals, which correlated with overactivation of the transforming growth factor-ß pathway. Altered regenerative response was associated with amplification of cytostatic effects of transforming growth factor-ß through induction of cell cycle negative regulators. Interestingly, lipid synthesis was severely inhibited in ΔEGFR livers after partial hepatectomy, revealing a new function for EGFR kinase activity as a lipid metabolism regulator in regenerating hepatocytes. In spite of these profound alterations, ΔEGFR livers were able to recover liver mass by overactivating compensatory signals, such as c-Met. Our results also indicate that EGFR catalytic activity is critical in the early preneoplastic stages of the liver because ΔEGFR mice showed a delay in the appearance of diethyl-nitrosamine-induced tumors, which correlated with decreased proliferation and delay in the diethyl-nitrosamine-induced inflammatory process. CONCLUSION: These studies demonstrate that EGFR catalytic activity is critical during the initial phases of both liver regeneration and carcinogenesis and provide key mechanistic insights into how this kinase acts to regulate liver pathophysiology. (Hepatology 2016;63:604-619).


Asunto(s)
Carcinogénesis , Receptores ErbB/fisiología , Neoplasias Hepáticas/etiología , Regeneración Hepática/fisiología , Animales , Catálisis , Humanos , Masculino , Ratones
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