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1.
Clin Gastroenterol Hepatol ; 17(4): 774-783.e4, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-29913280

RESUMO

BACKGROUND & AIMS: Caspase-mediated apoptosis and inflammation contribute to progression of liver disease. Emricasan is a pan-caspase inhibitor that reduced serum markers of apoptosis and liver inflammation in patients with hepatitis C and non-alcoholic steatohepatitis (NASH). METHODS: We performed a multicenter study of 86 patients with cirrhosis (Child-Pugh class A or B; mean score, 6.9; 38% with alcohol-associated cirrhosis, 29% with HCV-associated cirrhosis, and 23% with NASH) and model for end-stage liver disease (MELD) scores of 11-18 (mean, 12.8). Patients were randomly assigned to groups given placebo (N = 42) or Emricasan (25 mg, N = 44), twice daily for 3 months; subjects then received open-label Emricasan (25 mg) twice-daily for 3 months. The primary endpoint was the change from baseline in serum levels of cleaved keratin 18 (CK-18) at month 3. RESULTS: Seventy-four patients completed the 3-month study period (40 given Emricasan and 34 given placebo); 69 patients received open-label Emricasan for 3 months afterward. At the 3-month timepoint, Emricasan significantly reduced mean MELD (P = .003) and Child-Pugh (P = .003) scores in subjects with high MELD scores (15 or more), compared with placebo, with significant reductions in INR (95% CI, -0.2882 to -0.0866) and total bilirubin (95% CI, -1.5069 to -0.0823) vs placebo. There were no significant differences between Emricasan and placebo groups in mean MELD (P = .466) or Child-Pugh (P = .124) scores overall at 3 months compared to placebo. Of patients with high MELD scores, 6/9 given Emricasan (67%) had a reduction of 2 points or more at month 3, compared with 2/10 given placebo (20%). Serum levels of full-length CK-18 (P = .02) and caspase 3/7 (P < .001), but not cleaved CK-18 (P = .092), decreased significantly at 3 months in the Emricasan vs placebo group. Emricasan was well tolerated, and adverse events were balanced between groups. Emricasan's effects were generally maintained or increased after 6 months of treatment. CONCLUSIONS: In a randomized trial of patients with cirrhosis, we found 3 months treatment with Emricasan to improve liver function, compared with placebo, reducing MELD and Child-Pugh scores, INR, and total bilirubin in patients with MELD scores ≥15. ClinicalTrials.gov no: NCT02230670.


Assuntos
Inibidores de Caspase/uso terapêutico , Doença Hepática Terminal/tratamento farmacológico , Doença Hepática Terminal/patologia , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/patologia , Ácidos Pentanoicos/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Método Duplo-Cego , Feminino , Humanos , Queratina-18/sangue , Masculino , Pessoa de Meia-Idade , Placebos/administração & dosagem , Soro/química , Resultado do Tratamento
2.
Toxicol Appl Pharmacol ; 313: 47-56, 2016 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-27765658

RESUMO

BACKGROUND: Occupational vinyl chloride (VC) exposures have been associated with toxicant-associated steatohepatitis and liver cancer. Metabolomics has been used to clarify mode of action in drug-induced liver injury but has not been performed following VC exposures. METHODS: Plasma samples from 17 highly exposed VC workers without liver cancer and 27 unexposed healthy volunteers were obtained for metabolite extraction and GC/MS and LC/MS2 analysis. Following ion identification/quantification, Ingenuity pathway analysis was performed. RESULTS: 613 unique named metabolites were identified. Of these, 189 metabolites were increased in the VC exposure group while 94 metabolites were decreased. Random Forest analysis indicated that the metabolite signature could separate the groups with 94% accuracy. VC exposures were associated with increased long chain (including arachidonic acid) and essential (including linoleic acid) fatty acids. Occupational exposure increased lipid peroxidation products including monohydroxy fatty acids (including 13-HODE); fatty acid dicarboxylates; and oxidized arachidonic acid products (including 5,9, and 15-HETE). Carnitine and carnitine esters were decreased, suggesting peroxisomal/mitochondrial dysfunction and alternate modes of lipid oxidation. Differentially regulated metabolites were shown to interact with extracellular-signal-regulated kinase 1/2 (ERK1/2), Akt, AMP-activated protein kinase (AMPK), and the N-Methyl-d-aspartate (NMDA) receptor. The top canonical pathways affected by occupational exposure included tRNA charging, nucleotide degradation, amino acid synthesis/degradation and urea cycle. Methionine and homocysteine was increased with decreased cysteine, suggesting altered 1-carbon metabolism. CONCLUSIONS: Occupational exposure generated a distinct plasma metabolome with markedly altered lipid and amino acid metabolites. ERK1/2, Akt, AMPK, and NMDA were identified as protein targets for vinyl chloride toxicity.


Assuntos
Proteínas Sanguíneas/metabolismo , Metabolômica , Exposição Ocupacional , Cloreto de Polivinila/toxicidade , Adulto , Estudos de Casos e Controles , Humanos , Pessoa de Meia-Idade , Cloreto de Polivinila/síntese química
3.
Toxicol Appl Pharmacol ; 311: 34-41, 2016 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-27693805

RESUMO

BACKGROUND: Vinyl chloride (VC) causes toxicant-associated steatohepatitis at high exposure levels. Recent work by this group suggests that underlying liver disease may predispose the liver to VC hepatotoxicity at lower exposure levels. The most common form of underlying liver disease in the developed world is non-alcoholic fatty liver disease (NAFLD). It is well-known that the type of dietary fat can play an important role in the pathogenesis of NAFLD. However, whether the combination of dietary fat and VC/metabolites promotes liver injury has not been studied. METHODS: Mice were administered chloroethanol (CE - a VC metabolite) or vehicle once, 10weeks after being fed diets rich in saturated fatty acids (HSFA), rich in poly-unsaturated fatty acids (HPUFA), or the respective low-fat control diets (LSFA; LPUFA). RESULTS: In control mice, chloroethanol caused no detectable liver injury, as determined by plasma transaminases and histologic indices of damage. In HSFA-fed mice, chloroethanol increased HSFA-induced liver damage, steatosis, infiltrating inflammatory cells, hepatic expression of proinflammatory cytokines, and markers of endoplasmic reticulum (ER) stress. Moreover, markers of inflammasome activation were increased, while markers of inflammasome inhibition were downregulated. In mice fed HPUFA all of these effects were significantly attenuated. CONCLUSIONS: Chloroethanol promotes inflammatory liver injury caused by dietary fatty acids. This effect is far more exacerbated with saturated fat, versus poly-unsaturated fat; and strongly correlates with a robust activation of the NLRP3 inflammasome in the saturated fed animals only. Taken together these data support the hypothesis that environmental toxicant exposure can exacerbate the severity of NAFLD/NASH.


Assuntos
Gorduras na Dieta/farmacologia , Ácidos Graxos/farmacologia , Fígado/efeitos dos fármacos , Cloreto de Vinil/toxicidade , Animais , Gorduras na Dieta/administração & dosagem , Estresse do Retículo Endoplasmático , Ácidos Graxos/administração & dosagem , Expressão Gênica , Teste de Tolerância a Glucose , Mediadores da Inflamação/metabolismo , Lipídeos/sangue , Fígado/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL
4.
Toxicol Pathol ; 43(4): 482-97, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25326588

RESUMO

BACKGROUND: Toxicant-associated fatty liver disease (TAFLD) is a recently identified form of nonalcoholic fatty liver disease (NAFLD) associated with exposure to industrial chemicals and environmental pollutants. Numerous studies have been conducted to test the association between industrial chemicals/environmental pollutants and fatty liver disease both in vivo and in vitro. OBJECTIVES: The objective of the article is to report a list of chemicals associated with TAFLD. METHODS: Two federal databases of rodent toxicology studies-Toxicological Reference Database (ToxRefDB; Environmental Protection Agency) and Chemical Effects in Biological Systems (CEBS, National Toxicology Program)-were searched for liver end points. Combined, these 2 databases archive nearly 2,000 rodent studies. Toxicant-associated steatohepatitis (TASH) descriptors including fatty change, fatty necrosis, Oil red O-positive staining, steatosis, and lipid deposition were queried. RESULTS: Using these search terms, 123 chemicals associated with fatty liver were identified. Pesticides and solvents were the most frequently identified chemicals, while polychlorinated biphenyls (PCBs)/dioxins were the most potent. About 44% of identified compounds were pesticides or their intermediates, and >10% of pesticide registration studies in ToxRefDB were associated with fatty liver. Fungicides and herbicides were more frequently associated with fatty liver than insecticides. CONCLUSION: More research on pesticides, solvents, metals, and PCBs/dioxins in NAFLD/TAFLD is warranted due to their association with liver damage.


Assuntos
Poluentes Ambientais/toxicidade , Fígado/efeitos dos fármacos , Hepatopatia Gordurosa não Alcoólica/induzido quimicamente , Animais , Praguicidas/toxicidade , Testes de Toxicidade
5.
Toxicol Pathol ; 41(2): 343-60, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23262638

RESUMO

Hepatotoxicity is the most common organ injury due to occupational and environmental exposures to industrial chemicals. A wide range of liver pathologies ranging from necrosis to cancer have been observed following chemical exposures both in humans and in animal models. Toxicant-associated fatty liver disease (TAFLD) is a recently named form of liver injury pathologically similar to alcoholic liver disease (ALD) and nonalcoholic fatty liver disease (NAFLD). Toxicant-associated steatohepatitis (TASH) is a more severe form of TAFLD characterized by hepatic steatosis, inflammatory infiltrate, and in some cases, fibrosis. While subjects with TASH have exposures to industrial chemicals, such as vinyl chloride, they do not have traditional risk factors for fatty liver such as significant alcohol consumption or obesity. Conventional biomarkers of hepatotoxicity including serum alanine aminotransferase activity may be normal in TASH, making screening problematic. This article examines selected chemical exposures associated with TAFLD in human subjects or animal models and concisely reviews the closely related NAFLD and ALD.


Assuntos
Fígado Gorduroso/induzido quimicamente , Doenças Profissionais/induzido quimicamente , Animais , Biomarcadores , Histocitoquímica , Humanos , Exposição Ocupacional/efeitos adversos , Fatores de Risco , Cloreto de Vinil/intoxicação , Cloreto de Vinil/toxicidade
6.
Neuroradiol J ; 36(6): 702-706, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37382936

RESUMO

BACKGROUND: Intra-osseous vessels are normal anatomic structures in the calvarium and skull base. On imaging, these structures-particularly venous lakes-can mimic pathologic abnormalities. This study sought to assess the prevalence of veins and lakes in the skull base on MRI. MATERIALS AND METHODS: A retrospective review was completed of consecutive patients that underwent contrast-enhanced MRI imaging of the internal auditory canals. The clivus, jugular tubercles, and basio-occiput were assessed for the presence of both intra-osseous veins (serpentine and/or branching vessels) and venous lakes (well-circumscribed round or oval enhancing structures). Vessels in the adjacent synchondroses major foramina were excluded. Three board-certified neuroradiologists performed independent blinded reviews, with discrepancies agreed upon by consensus. RESULTS: 96 patients were included in this cohort (58.3% female). Mean age was 58.4 years (range = 19-85). At least one intra-osseous vessel was identified in 71 (74.0%) patients. 67 (70.0%) had at least one skull base vein, and 14 (14.6%) had at least one venous lake. Both vessel subtypes were observed in 8.3% of patients. Vessels were more commonly observed in women, though this did not reach statistical threshold (p = 0.56). Age was not associated with the presence of vessels (0.59) or vessel location (p values ranged from 0.44-0.84). CONCLUSIONS: Intra-osseous skull base veins and venous lakes are relatively common findings on MRI. Both vascular structures should be considered normal anatomy, and care should be taken to not confuse these for pathologic entities.


Assuntos
Base do Crânio , Veias , Humanos , Feminino , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Masculino , Prevalência , Veias/diagnóstico por imagem , Base do Crânio/diagnóstico por imagem , Crânio , Imageamento por Ressonância Magnética/métodos , Fossa Craniana Posterior
7.
Hepatology ; 51(2): 474-81, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19902480

RESUMO

UNLABELLED: Although nonalcoholic steatohepatitis (NASH) is typically associated with obesity, it has also been reported to occur in lean individuals exposed to industrial chemicals. Occupational exposure to vinyl chloride (VC) is a well-documented risk factor for hemangiosarcoma, but has not previously been associated with steatohepatitis. Here we evaluate liver biopsies from 25 nonobese, highly exposed VC workers for steatohepatitis. Next, we evaluate associated metabolic and cytokine abnormalities in affected workers controlled by 26 chemical workers with no to minimal VC exposures, and 11 unexposed, healthy volunteers. Among highly exposed VC workers the prevalence of steatohepatitis was 80%. Of these, 55% had fibrosis and four had hemangiosarcoma. We have coined the term toxicant-associated steatohepatitis (TASH) to describe this condition, which was not explained by obesity or alcohol. Although mean serum transaminases were normal in TASH, total cytokeratin 18, but not the caspase-cleaved fragment, was elevated. Despite the absence of obesity, workers with TASH had insulin resistance with reduced adiponectin levels. TASH was also associated with markedly elevated serum tumor necrosis factor alpha and interleukins 1beta, 6, and 8. Serum antioxidant activity was reduced in TASH. CONCLUSION: TASH occurred frequently in these nonobese VC workers with high cumulative exposures and normal liver enzymes. Elevated total cytokeratin 18 suggested the presence of necrotic cell death in TASH and may be a useful serologic biomarker. TASH was further characterized by insulin resistance, elevated proinflammatory cytokines, and impaired antioxidant defenses. The threshold VC exposure and the role of other chemical agents in TASH are as yet unknown.


Assuntos
Carcinógenos/toxicidade , Fígado Gorduroso/induzido quimicamente , Doenças Profissionais/induzido quimicamente , Cloreto de Vinil/toxicidade , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
8.
Hepatology ; 50(6): 1818-26, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19824078

RESUMO

UNLABELLED: Based on animal studies and pilot studies in humans, betaine, a methyl donor for the remethylation of homocysteine, may be a therapeutic agent for nonalcoholic steatohepatitis (NASH). We evaluated the safety and efficacy of betaine for patients with NASH and whether betaine positively modified factors postulated to be "second hits" and underlying mechanisms of NASH. We conducted a randomized placebo-control study of 55 patients with biopsy-proven NASH who received either oral betaine (20 g daily) or placebo for 12 months. Pre- and posttreatment variables were analyzed using the paired t test or Wilcoxon rank test. Treatment groups were comparable at baseline. Of the 35 patients (17 betaine, 18 placebo) who completed the study, 34 patients (16 betaine, 18 placebo) underwent posttreatment liver biopsy. Patients randomized to betaine had a decrease in steatosis grade. No intra- or intergroup differences or changes in nonalcoholic fatty liver disease activity score or fibrosis stage were noted. Elevations of insulin, glucose, and proinflammatory cytokines and the reduced antioxidant status noted in NASH patients did not improve with betaine therapy. The antiinflammatory agent adiponectin was significantly reduced in both groups and did not change with therapy. Lastly, S-adenosylhomocysteine was approximately twice normal and was not reduced by betaine therapy. CONCLUSION: Compared to placebo, betaine did not improve hepatic steatosis but may protect against worseningsteatosis [corrected]. High-dose betaine supplementation failed to reduce S-adenosylhomocysteine and did not positively affect any of the second hit mechanisms postulated to contribute to NASH that we studied. Although betaine has been proven effective in treating hepatic steatosis in several animal models, translating novel therapeutic options noted in animal studies to humans with NASH will prove challenging.


Assuntos
Betaína/uso terapêutico , Fígado Gorduroso/tratamento farmacológico , Adipocinas/sangue , Adulto , Idoso , Betaína/efeitos adversos , Citocinas/sangue , Método Duplo-Cego , Fígado Gorduroso/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , S-Adenosil-Homocisteína/sangue
9.
Curr Gastroenterol Rep ; 12(4): 288-95, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20640946

RESUMO

Nearly two thirds of American adults are either overweight or obese. Accordingly, bariatric surgery experienced explosive growth during the past decade. Current estimates place the worldwide volume of bariatric procedures at greater than 300,000 cases annually. Micronutrient deficiencies are well-described following bariatric surgery, and they may present with devastating and sometimes irreversible neurologic manifestations. Clinical symptoms range from peripheral neuropathy to encephalopathy, and are most commonly caused by thiamine, copper, and B(12) deficiencies.


Assuntos
Cirurgia Bariátrica/efeitos adversos , Encefalopatias Metabólicas/etiologia , Micronutrientes/deficiência , Obesidade Mórbida/complicações , Doenças do Sistema Nervoso Periférico/etiologia , Anastomose em-Y de Roux , Encefalopatias Metabólicas/fisiopatologia , Cobre/deficiência , Humanos , Obesidade Mórbida/metabolismo , Obesidade Mórbida/cirurgia , Doenças do Sistema Nervoso Periférico/cirurgia , Deficiência de Vitaminas do Complexo B/complicações
10.
Environ Health Perspect ; 127(12): 127007, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31858832

RESUMO

BACKGROUND: In 2014, we conducted a longitudinal study [Anniston Community Health Survey (ACHS II)] 8 y after the baseline (ACHS I). OBJECTIVES: We investigated the relationship between persistent chlorinated compounds and hypertension in residents living around the former polychlorinated biphenyl (PCB) production plant in Anniston, Alabama. We also examined the potential role of inflammatory cytokines in those with hypertension. METHODS: A total of 338 participants had their blood pressure measured and medications recorded, gave a blood sample, and completed a questionnaire. Prevalent hypertension was defined as taking antihypertensive medication or having systolic blood pressure >140 mmHg and/or diastolic pressure >90 mmHg; incident hypertension used similar criteria in those who developed hypertension since the baseline in 2005-2007. PCB congeners were categorized into structure-activity groups, and toxic equivalencies (TEQs) were calculated for dioxin-like compounds. Descriptive statistics, logistic and linear regressions, as well as Cox proportional hazard models, were used to analyze the associations between exposures and hypertension. RESULTS: Prevalent hypertension (78%) in ACHS II showed statistically significant adjusted odds ratios (ORs) for PCBs 74, 99, 138, 153, 167, 177, 183, and 187, ranging from 2.18 [95% confidence interval (CI): 1.10, 4.33] to 2.76 (95% CI: 1.14, 6.73), as well as for two estrogenic-like PCB groups, and the thyroid-like group [ORs ranging from 2.25 (95% CI: 1.07, 4.75) to 2.54 (95% CI: 1.13, 5.74)]. Furthermore, analysis of quartiles demonstrated a monotonic relationship for dioxin-like non-ortho (non-o)-PCB TEQs [fourth vs. first quartile: 3.66 (95% CI: 1.40, 9.56)]. Longitudinal analyses of incident hypertension supported those positive associations. The results were strongest for the di-o-PCBs [hazard ratio (HR)=1.93 (95% CI: 0.93, 4.00)] and estrogenic II PCB group [HR=1.90 (95% CI: 0.96, 3.78)] but were weaker for the dioxin TEQs. DISCUSSION: Findings supportive of positive associations were reported for dioxin-like mono-o- and non-o-PCBs as well as for nondioxin-like estrogenic and thyroid-like congeners with prevalent and incident hypertension, suggesting that multiple pathways may be involved in hypertension development. https://doi.org/10.1289/EHP5272.


Assuntos
Exposição Ambiental/estatística & dados numéricos , Poluentes Ambientais/sangue , Hipertensão/epidemiologia , Bifenilos Policlorados/sangue , Alabama , Feminino , Seguimentos , Inquéritos Epidemiológicos , Humanos , Hipertensão/sangue , Masculino , Saúde Pública
11.
Am Surg ; 74(5): 428-9, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18481501

RESUMO

This report documents the first known case of esophageal rupture occurring after chiropractic manipulation of the thoracic and lumbar spine for the treatment of back pain. Physicians should be aware of this potentially lethal complication of chiropractic medicine. The images are presented for educational purposes.


Assuntos
Doenças do Esôfago/etiologia , Manipulação Quiroprática/efeitos adversos , Dor nas Costas/terapia , Feminino , Humanos , Vértebras Lombares , Pessoa de Meia-Idade , Ruptura Espontânea , Síndrome , Vértebras Torácicas
12.
Nutr Clin Pract ; 23(1): 16-34, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18203961

RESUMO

Obesity is an emerging problem worldwide. Hospitalized obese patients often have a worse outcome than patients of normal weight, particularly in the setting of trauma and critical care. Obesity creates a low-grade systemic inflammatory response syndrome (SIRS) that is similar (but on a much smaller scale) to gram-negative sepsis. This process involves up-regulation of systemic immunity, is characterized clinically by insulin resistance and the metabolic syndrome, and puts the patient at increased risk for organ failure, infectious morbidity, and mortality. Through lipotoxicity and cytokine dysregulation, obesity may act to prime the immune system, predisposing to an exaggerated subsequent immune response when a second clinical insult occurs (such as trauma, burns, or myocardial infarction). Specialized nutrition therapy for such patients currently consists of a hypocaloric, high-protein diet. However, this approach does not address the putative pathophysiologic mechanisms of inflammation and altered metabolism associated with obesity. A number of dietary agents such as arginine, fish oil, and carnitine may correct these problems at the molecular level. Pharmaconutrition formulas may provide exciting innovations for the nutrition therapy of the obese patient.


Assuntos
Estado Terminal/terapia , Terapia Nutricional , Obesidade/terapia , Síndrome de Resposta Inflamatória Sistêmica/terapia , Citocinas/metabolismo , Humanos , Resistência à Insulina , Obesidade/imunologia , Prognóstico , Síndrome de Resposta Inflamatória Sistêmica/imunologia , Resultado do Tratamento
13.
Health Equity ; 2(1): 103-108, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30283855

RESUMO

Purpose: Referral access to subspecialty care for patients with gastrointestinal (GI) diseases is not well defined, but has significant importance to patients. We hypothesized that patients experience barriers to care in two common gastroenterology subspecialties, Hepatology and Motility, in a university medical center. Methods: Two hundred thirteen clinic patients (mean age 46.5 years; 66.5% female; 85.6% Caucasians) completed a formatted questionnaire on access to care. Hepatology patients were older (49.7 years, p=0.008); motility patients predominantly female (76.8%, p<0.001). Gender distribution was even for hepatology (51.2% female). Both groups were overweight (mean body mass index 28.4). Results: Patients waited a mean 89.5 days to be seen by a subspecialist. There were differences by subspecialty (107.6 days for motility vs. 64.3 days for hepatology, p=0.022). A larger percentage of motility patients were told nothing was wrong with them (16.8%, p<0.01) and could not be helped (42.1%, p=0.000). Conclusions: Access to care for subspecialty gastroenterology patients in a university center appears to be impacted by a number of variables. While there are similarities, differences exist between these two subspecialties. Motility patients were more likely to have been told they have nothing wrong with them, suffer setbacks financially, and suffer mood problems. Their wait time for appointments was also greater than hepatology patients. Further investigations of referral access for gastroenterology patients may yield additional insights into disease-specific barriers to accessing subspecialty care.

14.
Toxicol Sci ; 151(2): 312-23, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26962056

RESUMO

Vinyl chloride (VC) is a ubiquitous environmental contaminant for which human risk is incompletely understood. We have previously reported that high occupational exposure to VC directly caused liver damage in humans. However, whether VC may also potentiate liver injury from other causes is not known. C57Bl/6J mice were administered chloroethanol (CE), a major metabolite of VC, and lipopolysaccharide (LPS) 24 h after CE. Samples were harvested for determination of liver damage, inflammation, and changes in carbohydrate and lipid metabolism. In mice, CE exposure alone caused no detectable liver damage. LPS exposure caused inflammatory liver damage, oxidative stress, lipid accumulation, and glycogen depletion; the effect of all of these variables was potentiated by CE pre-exposure. In vitro experiments suggest that VC metabolite chloroacetaldehyde (CAA) directly damages mitochondria, which may explain the sensitization effect observed in vivo Moreover, co-exposure of cells to CAA and TNFα caused increased cell death, supporting the hypothesis of sensitization by VC metabolites. Taken together, these data demonstrate that exposure to VC/metabolites at levels that are not overtly hepatotoxic can potentiate liver injury caused by another hepatotoxicant. This serves as proof-of-concept that VC hepatotoxicity may be modified by an additional metabolic stress such as endotoxemia, which commonly occurs in acute (eg, sepsis) and chronic (eg, NAFLD) diseases.


Assuntos
Acetaldeído/análogos & derivados , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Lipopolissacarídeos/toxicidade , Fígado/efeitos dos fármacos , Cloreto de Vinil/toxicidade , Proteínas Quinases Ativadas por AMP/metabolismo , Acetaldeído/metabolismo , Acetaldeído/toxicidade , Animais , Metabolismo dos Carboidratos/efeitos dos fármacos , Doença Hepática Induzida por Substâncias e Drogas/genética , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/patologia , Regulação da Expressão Gênica/efeitos dos fármacos , Células Hep G2 , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Masculino , Camundongos Endogâmicos C57BL , Mitocôndrias Hepáticas/efeitos dos fármacos , Mitocôndrias Hepáticas/metabolismo , Mitocôndrias Hepáticas/patologia , Fosforilação , Serina-Treonina Quinases TOR/metabolismo , Fatores de Tempo , Cloreto de Vinil/metabolismo
15.
JPEN J Parenter Enteral Nutr ; 39(8): 977-85, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25185153

RESUMO

Neurologic complications are not uncommon following bariatric surgery. Hyperammonemic encephalopathy (HAE) due to an acquired or unmasked urea cycle deficit is among the rarest of these. Pediatric nutrition support specialists are familiar with recognizing urea cycle deficits, but adult specialists may not be. Here we present a case of a patient initially misdiagnosed with cirrhosis who presented with recurrent HAE 4 years after Roux-en-Y gastric bypass. She was diagnosed with a proximal urea cycle deficit and severe protein calorie malnutrition. The patient recovered with specialized nutrition and medical support targeting this condition. A literature review indicates multiple fatalities from this condition, indicating the importance of early diagnosis and appropriate nutrition support.


Assuntos
Amônia/sangue , Encefalopatias Metabólicas/diagnóstico , Derivação Gástrica/efeitos adversos , Desnutrição Proteico-Calórica/etiologia , Adulto , Encefalopatias Metabólicas/sangue , Encefalopatias Metabólicas/etiologia , Erros de Diagnóstico , Feminino , Fibrose/diagnóstico , Humanos , Pessoa de Meia-Idade , Ureia/sangue
16.
Adv Pharmacol ; 74: 1-33, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26233902

RESUMO

The purpose of this chapter is to provide insight into which human cytochromes P450 (CYPs) may be involved in metabolism of chemical carcinogens and anticancer drugs. A historical overview of this field and the development of literature using relevant animal models and expressed human CYPs have provided information about which specific CYPs may be involved in carcinogen metabolism. Definition of the biochemical properties of CYP activity came from several groups who studied the reaction stoichiometry of butter yellow and benzo[α]pyrene, including their role in induction of these enzyme systems. This chapter will list as much as is known about the human CYPs involved in carcinogen and anticancer drug metabolism, as well as summarize studies with rodent CYPs. A review of three major classes of anticancer drugs and their metabolism in humans is covered for cyclophosphamide, procarbazine, and anthracycline antibiotics, cancer chemotherapeutic compounds extensively metabolized by CYPs. The emerging information about human CYP gene polymorphisms as well as other enzymes involved in foreign compound metabolism provides considerable information about how these genetic variants affect carcinogen and anticancer drug metabolism. With information available from individual's genomic sequences, consideration of populations who may be at risk due to environmental exposure to carcinogens or how to optimize their cancer therapy regimens to enhance efficacy of the anticancer drugs appears to be an important field of study to benefit individuals in the future.


Assuntos
Antineoplásicos/metabolismo , Carcinógenos/metabolismo , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Animais , Humanos , Polimorfismo Genético/genética
17.
J Nutr Biochem ; 24(9): 1587-95, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23618531

RESUMO

BACKGROUND: Polychlorinated biphenyls (PCBs) are persistent environmental pollutants that are detectable in the serum of all American adults. Amongst PCB congeners, PCB 153 has the highest serum level. PCBs have been dose-dependently associated with obesity, metabolic syndrome and nonalcoholic fatty liver disease (NAFLD) in epidemiological studies. OBJECTIVE: The purpose of this study is to determine mechanisms by which PCB 153 worsens diet-induced obesity and NAFLD in male mice fed a high-fat diet (HFD). METHODS: Male C57BL6/J mice were fed either control or 42% milk fat diet for 12 weeks with or without PCB 153 coexposure (50 mg/kg ip ×4). Glucose tolerance test was performed, and plasma and tissues were obtained at necropsy for measurements of adipocytokine levels, histology and gene expression. RESULTS: In control diet-fed mice, addition of PCB 153 had minimal effects on any of the measured parameters. However, PCB 153 treatment in high-fat-fed mice was associated with increased visceral adiposity, hepatic steatosis and plasma adipokines including adiponectin, leptin, resistin and plasminogen activator inhibitor-1 levels. Likewise, coexposure reduced expression of hepatic genes implicated in ß-oxidation while increasing the expression of genes associated with lipid biosynthesis. Regardless of diet, PCB 153 had no effect on insulin resistance or tumor necrosis factor alpha levels. CONCLUSION: PCB 153 is an obesogen that exacerbates hepatic steatosis, alters adipocytokines and disrupts normal hepatic lipid metabolism when administered with HFD but not control diet. Because all US adults have been exposed to PCB 153, this particular nutrient-toxicant interaction potentially impacts human obesity/NAFLD.


Assuntos
Fígado Gorduroso/sangue , Obesidade/sangue , Bifenilos Policlorados/toxicidade , Adiponectina/sangue , Animais , Dieta Hiperlipídica , Modelos Animais de Doenças , Poluentes Ambientais/administração & dosagem , Poluentes Ambientais/sangue , Poluentes Ambientais/toxicidade , Fígado Gorduroso/induzido quimicamente , Teste de Tolerância a Glucose , Resistência à Insulina , Leptina/sangue , Lipogênese , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica , Obesidade/induzido quimicamente , Inibidor 1 de Ativador de Plasminogênio/sangue , Bifenilos Policlorados/administração & dosagem , Bifenilos Policlorados/sangue , Resistina/sangue
18.
JPEN J Parenter Enteral Nutr ; 35(5 Suppl): 60S-72S, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21881016

RESUMO

Obesity is an epidemic that affects approximately 30% of the adult population in the United States. The prevalence of obesity in the critically ill seems to correlate with the rise in obesity in the general population. Delivery of standard enteral nutrition (EN) to patients in the intensive care unit (ICU) has been shown to decrease infectious complications. Obese ICU patients may be at increased risk for infections, ICU length of stay, and ventilation requirements compared to the nonobese. Pharmaconutrition has been shown to decrease many of these negative ICU outcomes. Because of obesity-associated increased ICU risk, provision of certain pharmaconutrients should be considered in obese patients requiring EN therapy. This review examines the evidence for specific nutrients such as green tea, curcumin, sulforaphane, poly-unsaturated fatty acids, L-arginine, L-citrulline, L-leucine, protein, probiotics, magnesium, medium-chain triglycerides, and zinc for the treatment of obesity. These nutrients could potentially be added to current EN formulas or provided as supplements.


Assuntos
Antioxidantes/farmacologia , Estado Terminal/terapia , Suplementos Nutricionais , Nutrição Enteral/métodos , Obesidade/epidemiologia , Obesidade/terapia , Arginina/farmacologia , Citrulina/farmacologia , Cuidados Críticos , Proteínas Alimentares/farmacologia , Ácidos Graxos Insaturados/farmacologia , Humanos , Doenças Inflamatórias Intestinais/complicações , Doenças Inflamatórias Intestinais/terapia , Unidades de Terapia Intensiva , Tempo de Internação , Leucina/farmacologia , Magnésio/farmacologia , Obesidade/complicações , Estresse Oxidativo , Prebióticos , Probióticos/uso terapêutico , Resultado do Tratamento , Estados Unidos/epidemiologia , Ventilação , Zinco/farmacologia
19.
J Occup Environ Med ; 53(10): 1128-33, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21915069

RESUMO

OBJECTIVE: Cytokeratin 18 (CK18) is a novel serologic biomarker for occupational liver disease. The purpose of this study is to determine the prevalence of CK18 elevation in elastomer/polymer workers exposed to acrylonitrile, 1,3-butadiene, and styrene. METHODS: A total of 82 chemical workers were evaluated. Cytokeratin 18 was determined by enzyme-linked immunosorbent assay and proinflammatory cytokines were measured by multi-analyte chemiluminescent detection. RESULTS: Thirty-nine percent (32 of 82) had elevated CK18 levels, which were not explained by alcohol or obesity, except in potentially four cases. The pattern of CK18 elevation was consistent with toxicant-associated steatohepatitis (TASH) in the majority of cases (78%). Tumor necrosis factor α, interleukin-6, interleukin-8, monocyte chemotactic protein-1, and plasminogen activator inhibitor-1 were increased in these workers compared with those with normal CK18 levels. CONCLUSIONS: These results suggest a high prevalence of occupational liver disease and TASH in elastomer/polymer workers with elevated proinflammatory cytokines.


Assuntos
Acrilonitrila/efeitos adversos , Butadienos/efeitos adversos , Doença Hepática Induzida por Substâncias e Drogas/sangue , Citocinas/sangue , Fígado Gorduroso/sangue , Queratina-18/sangue , Doenças Profissionais/sangue , Estireno/efeitos adversos , Adulto , Quimiocina CCL2/sangue , Elastômeros/efeitos adversos , Fígado Gorduroso/induzido quimicamente , Humanos , Interleucina-1/sangue , Interleucina-6/sangue , Modelos Lineares , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Doenças Profissionais/induzido quimicamente , Inibidor 1 de Ativador de Plasminogênio/sangue , Polímeros/efeitos adversos , Estatísticas não Paramétricas , Fator de Necrose Tumoral alfa/sangue
20.
J Nutr Biochem ; 22(1): 38-45, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20303728

RESUMO

Nonalcoholic fatty liver disease (NAFLD) is the most common form of liver disease in the US and refers to a wide spectrum of liver damage, including simple steatosis, steatohepatitis, fibrosis and cirrhosis. The goal of the present study was to achieve a more detailed understanding of the molecular changes in response to high fat-induced liver steatosis through the identification of a differentially expressed liver transcriptome and proteome. Male C57/BL6 mice fed a high-fat lard diet for 8 weeks developed visceral obesity and hepatic steatosis characterized by significantly increased liver and plasma free fatty acid and triglyceride levels and plasma alanine aminotransferase activities. Transcriptome analysis demonstrated that, compared to the control diet (CD), high-fat diet changed the expression of 309 genes (132 up- and 177 down-regulated; by a twofold change and more, P<.05). Multiple genes encoding proteins involved in lipogenesis were down-regulated, whereas genes involved in fatty acid oxidation were up-regulated. Proteomic analysis revealed 12 proteins which were differentially expressed. Of these, glutathione S-transferases mu1 and pi1 and selenium-binding protein 2 were decreased at both the gene and protein levels. This is the first study to perform a parallel transcriptomic and proteomic analysis of diet-induced hepatic steatosis. Several key pathways involving xenobiotic and lipid metabolism, the inflammatory response and cell-cycle control were identified. These pathways provide targets for future mechanistic and therapeutic studies as related to the development and prevention of NAFLD.


Assuntos
Fígado Gorduroso/metabolismo , Regulação da Expressão Gênica , Fígado/metabolismo , Proteoma/metabolismo , Animais , Gorduras na Dieta/efeitos adversos , Ácidos Graxos/metabolismo , Fígado Gorduroso/patologia , Perfilação da Expressão Gênica , Glutationa S-Transferase pi/química , Glutationa S-Transferase pi/genética , Glutationa S-Transferase pi/metabolismo , Glutationa Transferase/química , Glutationa Transferase/genética , Glutationa Transferase/metabolismo , Lipogênese , Fígado/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Análise de Sequência com Séries de Oligonucleotídeos , Proteoma/química , Proteoma/genética , RNA Mensageiro/metabolismo , Proteínas de Ligação a Selênio/química , Proteínas de Ligação a Selênio/genética , Proteínas de Ligação a Selênio/metabolismo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Espectrometria de Massas em Tandem , Eletroforese em Gel Diferencial Bidimensional
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