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1.
Hepatology ; 72(5): 1617-1637, 2020 11.
Article in English | MEDLINE | ID: mdl-32086945

ABSTRACT

BACKGROUND AND AIMS: Alcohol-associated liver disease (ALD) is a common chronic liver disease worldwide with high morbidity and mortality, and no Food and Drug Administration-approved therapies. Fructose (dietary or endogenous), its metabolite uric acid, and aldose reductase (AR, the only endogenous enzyme that produces fructose) are strongly associated with the development of nonalcoholic fatty liver disease. However, the role of AR or its metabolites in ALD remains understudied and was examined using human specimens, cultured cells, and mouse model systems. APPROACH AND RESULTS: We demonstrated in liver specimens from patients with alcoholic hepatitis, the AR up-regulation and elevated AR metabolites (sorbitol, fructose, and uric acid), which correlated significantly with (1) increased lipid peroxidation byproducts and endoplasmic reticulum (ER) stress, (2) decreased protective ER chaperones, and (3) greater cell death and liver injury. Furthermore, we established a causal role for AR in ALD by showing that the genetic deficiency of AR (knockout mice) prevented alcohol-induced increase in harmful AR metabolites, toxic aldehydes, steatosis, ER stress, apoptosis, and liver injury. Finally, we demonstrated the therapeutic potential of pharmacological AR inhibition against alcohol-induced hepatic injury in experimental ALD. CONCLUSIONS: Our data demonstrate that hepatic AR up-regulation, and consequent elevation in fructose, sorbitol and/or uric acid, are important factors contributing to alcohol-induced steatosis, ER stress, apoptosis, and liver injury in both experimental and human ALD. Our study provides a strong rationale to evaluate AR as a potential therapeutic target and to test AR inhibitors to ameliorate alcohol-induced liver injury.


Subject(s)
Aldehyde Reductase/metabolism , Fructose/blood , Hydroxyprostaglandin Dehydrogenases/metabolism , Liver Diseases, Alcoholic/metabolism , Uric Acid/blood , Adult , Aldehyde Reductase/genetics , Animals , Apoptosis/drug effects , Case-Control Studies , Cohort Studies , Disease Models, Animal , Endoplasmic Reticulum Stress/drug effects , Ethanol/administration & dosage , Ethanol/toxicity , Female , Fructose/metabolism , Humans , Hydroxyprostaglandin Dehydrogenases/genetics , Liver/drug effects , Liver/pathology , Liver Diseases, Alcoholic/blood , Liver Diseases, Alcoholic/diagnosis , Liver Diseases, Alcoholic/etiology , Male , Mice , Mice, Knockout , Middle Aged , Oxidative Stress/drug effects , Severity of Illness Index , Sorbitol/blood , Sorbitol/metabolism , Up-Regulation/drug effects , Uric Acid/metabolism
2.
AIDS Behav ; 25(9): 2852-2862, 2021 Sep.
Article in English | MEDLINE | ID: mdl-34101074

ABSTRACT

Unhealthy alcohol use, smoking, and depressive symptoms are risk factors for cardiovascular disease (CVD). Little is known about their co-occurrence - termed a syndemic, defined as the synergistic effect of two or more conditions-on CVD risk in people with HIV (PWH). We used data from 5621 CVD-free participants (51% PWH) in the Veteran's Aging Cohort Study-8, a prospective, observational study of veterans followed from 2002 to 2014 to assess the association between this syndemic and incident CVD by HIV status. Diagnostic codes identified cases of CVD (acute myocardial infarction, stroke, heart failure, peripheral artery disease, and coronary revascularization). Validated measures of alcohol use, smoking, and depressive symptoms were used. Baseline number of syndemic conditions was categorized (0, 1, ≥ 2 conditions). Multivariable Cox Proportional Hazards regressions estimated risk of the syndemic (≥ 2 conditions) on incident CVD by HIV-status. There were 1149 cases of incident CVD (52% PWH) during the follow-up (median 10.1 years). Of the total sample, 64% met our syndemic definition. The syndemic was associated with greater risk for incident CVD among PWH (Hazard Ratio [HR] 1.87 [1.47-2.38], p < 0.001) and HIV-negative veterans (HR 1.70 [1.35-2.13], p < 0.001), compared to HIV-negative with zero conditions. Among those with the syndemic, CVD risk was not statistically significantly higher among PWH vs. HIV-negative (HR 1.10 [0.89, 1.37], p = .38). Given the high prevalence of this syndemic combined with excess risk of CVD, these findings support linked-screening and treatment efforts.


Subject(s)
Cardiovascular Diseases , HIV Infections , Veterans , Cardiovascular Diseases/epidemiology , Cohort Studies , Depression/epidemiology , HIV Infections/complications , HIV Infections/epidemiology , Humans , Incidence , Prospective Studies , Risk Factors , Smoking/epidemiology , Syndemic
3.
Am J Pathol ; 187(12): 2686-2697, 2017 Dec.
Article in English | MEDLINE | ID: mdl-28935573

ABSTRACT

Increasing evidence suggests that environmental and dietary factors can affect intestinal epithelial integrity leading to gut permeability and bacterial translocation. Intestinal barrier dysfunction is a pathogenic process associated with many chronic disorders. Acrolein is an environmental and dietary pollutant and a lipid-derived endogenous metabolite. The impact of acrolein on the intestine has not been investigated before and is evaluated in this study, both in vitro and in vivo. Our data demonstrate that oral acrolein exposure in mice caused damage to the intestinal epithelial barrier, resulting in increased permeability and subsequently translocation of bacterial endotoxin-lipopolysaccharide into the blood. Similar results were seen in vitro using established Caco-2 cell monolayers wherein acrolein decreased barrier function and increased permeability. Acrolein also caused the down-regulation and/or redistribution of three representative tight junction proteins (ie, zonula occludens-1, Occludin, Claudin-1) that critically regulate epithelial paracellular permeability. In addition, acrolein induced endoplasmic reticulum stress-mediated death of epithelial cells, which is an important mechanism contributing to intestinal barrier damage/dysfunction, and gut permeability. Overall, we demonstrate that exposure to acrolein affects the intestinal epithelium by decrease/redistribution of tight junction proteins and endoplasmic reticulum stress-mediated epithelial cell death, thereby resulting in loss of barrier integrity and function. Our findings highlight the adverse consequences of environmental and dietary pollutants on intestinal barrier integrity/function with relevance to gut permeability and the development of disease.


Subject(s)
Acrolein/toxicity , Apoptosis/drug effects , Endoplasmic Reticulum Stress/drug effects , Intestinal Mucosa/drug effects , Tight Junction Proteins/drug effects , Animals , Caco-2 Cells , Humans , Intestinal Mucosa/pathology , Male , Mice , Mice, Inbred C57BL , Permeability/drug effects , Tight Junction Proteins/metabolism
4.
BMC Cancer ; 18(1): 421, 2018 04 13.
Article in English | MEDLINE | ID: mdl-29653561

ABSTRACT

BACKGROUND: Dysregulation of microRNA (miRNA) expression is associated with hallmarks of aggressive tumor phenotypes, e.g., enhanced cell growth, proliferation, invasion, and anchorage independent growth in prostate cancer (PCa). METHODS: Serum-based miRNA profiling involved 15 men diagnosed with non-metastatic (stage I, III) and metastatic (stage IV) PCa and five age-matched disease-free men using miRNA arrays with select targets confirmed by quantitative real-time PCR (qRT-PCR). The effect of miR-186-5p inhibition or ectopic expression on cellular behavior of PCa cells (i.e., PC-3, MDA-PCa-2b, and LNCaP) involved the use bromodeoxyuridine (BrdU) incorporation, invasion, and colony formation assays. Assessment of the impact of miR-186-5p inhibition or overexpression on selected targets entailed microarray analysis, qRT-PCR, and/or western blots. Statistical evaluation used the modified t-test and ANOVA analysis. RESULTS: MiR-186-5p was upregulated in serum from PCa patients and metastatic PCa cell lines (i.e., PC-3, MDA-PCa-2b, LNCaP) compared to serum from disease-free individuals or a normal prostate epithelial cell line (RWPE1), respectively. Inhibition of miR-186-5p reduced cell proliferation, invasion, and anchorage-independent growth of PC-3 and/or MDA-PCa-2b PCa cells. AKAP12, a tumor suppressor target of miR-186-5p, was upregulated in PC-3 and MDA-PCa-2b cells transfected with a miR-186-5p inhibitor. Conversely, ectopic miR-186-5p expression in HEK 293 T cells decreased AKAP12 expression by 30%. Both pAKT and ß-catenin levels were down-regulated in miR-186-5p inhibited PCa cells. CONCLUSIONS: Our findings suggest miR-186-5p plays an oncogenic role in PCa. Inhibition of miR-186-5p reduced PCa cell proliferation and invasion as well as increased AKAP12 expression. Future studies should explore whether miR-186-5p may serve as a candidate prognostic indicator and a therapeutic target for the treatment of aggressive prostate cancer.


Subject(s)
MicroRNAs/genetics , Prostatic Neoplasms/genetics , Prostatic Neoplasms/pathology , A Kinase Anchor Proteins/genetics , Cell Cycle Proteins/genetics , Cell Line, Tumor , Cell Proliferation/genetics , Circulating MicroRNA , Gene Expression Profiling , Gene Expression Regulation, Neoplastic , Humans , Male , MicroRNAs/blood , Neoplasm Invasiveness , Neoplasm Metastasis , Neoplasm Staging , Prostatic Neoplasms/blood , Proto-Oncogene Proteins c-akt/genetics , Proto-Oncogene Proteins c-akt/metabolism , Reproducibility of Results , Transcriptome , beta Catenin/genetics
5.
Am J Pathol ; 186(4): 765-76, 2016 Apr.
Article in English | MEDLINE | ID: mdl-27012191

ABSTRACT

Alcoholic liver disease (ALD) ranks among major causes of morbidity and mortality. Diet and crosstalk between the gut and liver are important determinants of ALD. We evaluated the effects of different types of dietary fat and ethanol on the gut microbiota composition and metabolic activity and the effect of these changes on liver injury in ALD. Compared with ethanol and a saturated fat diet (medium chain triglycerides enriched), an unsaturated fat diet (corn oil enriched) exacerbated ethanol-induced endotoxemia, liver steatosis, and injury. Major alterations in gut microbiota, including a reduction in Bacteroidetes and an increase in Proteobacteria and Actinobacteria, were seen in animals fed an unsaturated fat diet and ethanol but not a saturated fat diet and ethanol. Compared with a saturated fat diet and ethanol, an unsaturated fat diet and ethanol caused major fecal metabolomic changes. Moreover, a decrease in certain fecal amino acids was noted in both alcohol-fed groups. These data support an important role of dietary lipids in ALD pathogenesis and provide insight into mechanisms of ALD development. A diet enriched in unsaturated fats enhanced alcohol-induced liver injury and caused major fecal metagenomic and metabolomic changes that may play an etiologic role in observed liver injury. Dietary lipids can potentially serve as inexpensive interventions for the prevention and treatment of ALD.


Subject(s)
Dietary Fats, Unsaturated/metabolism , Dietary Fats/metabolism , Ethanol/pharmacology , Gastrointestinal Microbiome/drug effects , Liver Diseases, Alcoholic/metabolism , Animals , Disease Models, Animal , Liver/metabolism , Male , Mice, Inbred C57BL , Triglycerides/metabolism
6.
Alcohol Clin Exp Res ; 40(10): 2085-2093, 2016 10.
Article in English | MEDLINE | ID: mdl-27589090

ABSTRACT

BACKGROUND: Heavy alcohol consumption frequently causes liver inflammation/injury, and certain fatty acids (FAs) may be involved in this liver pathology. In this study, we evaluated the association of heavy drinking and the changes in the FA levels involved in the ω-6 (pro-inflammatory) and ω-3 (anti-inflammatory) state in alcohol-dependent (AD) patients who had no clinical manifestations of liver injury. We aimed to identify sex-based differences in patients with mild or no biochemical evidence of liver injury induced by heavy drinking. METHODS: A total of 114 heavy drinking AD female and male patients aged 21 to 65 years without clinical manifestations of liver injury, who were admitted to an alcohol dependence treatment program, were grouped by the alanine aminotransferase (ALT) levels: ≤40 IU/l, as no liver injury (GR.1), and >40 IU/l, as mild liver injury (GR.2). Patients were actively drinking until the day of admission. Comprehensive metabolic panel, comprehensive FA panel, and drinking history data were evaluated. RESULTS: Elevated ALT and aspartate aminotransferase (AST) showed close association with markers of heavy alcohol intake. In the patients with mild biochemical liver injury (GR.2), females showed significantly higher AST level than males. Significant association of AST and total drinks in past 90 days (TD90) in females, and AST and heavy drinking days in past 90 days (HDD90) in males was observed. The ω-6:ω-3 ratio showed a significant pro-inflammatory response only in females with mild liver injury (GR.2) when adjusted by drinking history marker, TD90. Docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) were increased in males with liver injury, while females did not show any comparable rise in EPA; and DHA levels were lower. CONCLUSIONS: Measures of heavy drinking, TD90 and HDD90, predicted changes in liver injury. Changes in the ω-3 and ω-6 FA levels and the ω-6:ω-3 ratio showed a pro-inflammatory shift in patients with biochemical liver injury with a significant effect in females. Changes in FAs involved in the inflammatory state may represent one mechanism for liver inflammation/injury in response to heavy alcohol drinking.


Subject(s)
Alanine Transaminase/blood , Alcohol Drinking/adverse effects , Alcohol Drinking/blood , Alcoholism/blood , Aspartate Aminotransferases/blood , Fatty Acids, Omega-3/blood , Fatty Acids, Omega-6/blood , Liver Diseases, Alcoholic/blood , Adult , Aged , Alcoholism/complications , Biomarkers/blood , Docosahexaenoic Acids/blood , Eicosapentaenoic Acid/blood , Female , Humans , Liver Diseases, Alcoholic/complications , Male , Middle Aged , Prodromal Symptoms , Sex Characteristics , Young Adult
7.
J Immunol ; 193(1): 412-21, 2014 Jul 01.
Article in English | MEDLINE | ID: mdl-24899502

ABSTRACT

Activation-induced Fas ligand (FasL) mRNA expression in CD4+ T cells is mainly controlled at transcriptional initiation. To elucidate the epigenetic mechanisms regulating physiologic and pathologic FasL transcription, TCR stimulation-responsive promoter histone modifications in normal and alcohol-exposed primary human CD4+ T cells were examined. TCR stimulation of normal and alcohol-exposed cells led to discernible changes in promoter histone H3 lysine trimethylation, as documented by an increase in the levels of transcriptionally permissive histone 3 lysine 4 trimethylation and a concomitant decrease in the repressive histone 3 lysine 9 trimethylation. Moreover, acetylation of histone 3 lysine 9 (H3K9), a critical feature of the active promoter state that is opposed by histone 3 lysine 9 trimethylation, was significantly increased and was essentially mediated by the p300-histone acetyltransferase. Notably, the degree of these coordinated histone modifications and subsequent recruitment of transcription factors and RNA polymerase II were significantly enhanced in alcohol-exposed CD4+ T cells and were commensurate with the pathologic increase in the levels of FasL mRNA. The clinical relevance of these findings is further supported by CD4+ T cells obtained from individuals with a history of heavy alcohol consumption, which demonstrate significantly greater p300-dependent H3K9 acetylation and FasL expression. Overall, these data show that, in human CD4+ T cells, TCR stimulation induces a distinct promoter histone profile involving a coordinated cross-talk between histone 3 lysine 4 and H3K9 methylation and acetylation that dictates the transcriptional activation of FasL under physiologic, as well as pathologic, conditions of alcohol exposure.


Subject(s)
Alcohol Drinking/immunology , CD4-Positive T-Lymphocytes/immunology , Fas Ligand Protein/immunology , Gene Expression Regulation/immunology , Histones/immunology , Receptors, Antigen, T-Cell/immunology , Alcohol Drinking/adverse effects , Alcohol Drinking/pathology , CD4-Positive T-Lymphocytes/pathology , Female , Humans , Male , Methylation , p300-CBP Transcription Factors/immunology
8.
Nutrients ; 15(20)2023 Oct 17.
Article in English | MEDLINE | ID: mdl-37892472

ABSTRACT

PURPOSE: Chemokine-driven leukocyte infiltration and sustained inflammation contribute to alcohol-associated liver disease (ALD). Elevated hepatic CCL2 expression, seen in ALD, is associated with disease severity. However, mechanisms of CCL2 regulation are not completely elucidated. Post-translational modifications (PTMs) of proteins, particularly acetylation, modulate gene expression. This study examined the acetylation changes of promoter-associated histone-H3 and key transcription factor-NFκB in regulating hepatic CCL2 expression and subsequent inflammation and injury. Further, the effect of therapeutic modulation of the acetylation state by tributyrin (TB), a butyrate prodrug, was assessed. METHODS: Hepatic CCL2 expression was assessed in mice fed control (PF) or an ethanol-containing Lieber-DeCarli (5% v/v, EF) diet for 7 weeks with or without oral administration of tributyrin (TB, 2 g/kg, 5 days/week). A chromatin immunoprecipitation (ChIP) assay evaluated promoter-associated modifications. Nuclear association between SIRT1, p300, and NFκB-p65 and acetylation changes of p65 were determined using immunoprecipitation and Western blot analyses. A Student's t-test and one-way ANOVA determined the significance. RESULTS: Ethanol significantly increased promoter-associated histone-H3-lysine-9 acetylation (H3K9Ac), reflecting a transcriptionally permissive state with a resultant increase in hepatic CCL2 mRNA and protein expression. Moreover, increased lysine-310-acetylation of nuclear RelA/p65 decreased its association with SIRT1, a class III HDAC, but concomitantly increased with p300, a histone acetyltransferase. This further led to enhanced recruitment of NF-κB/p65 and RNA polymerase-II to the CCL2 promoter. Oral TB administration prevented ethanol-associated acetylation changes, thus downregulating CCL2 expression, hepatic neutrophil infiltration, and inflammation/ injury. CONCLUSION: The modulation of a protein acetylation state via ethanol or TB mechanistically regulates hepatic CCL2 upregulation in ALD.


Subject(s)
Hepatitis , Histones , Mice , Animals , Histones/metabolism , NF-kappa B/metabolism , Ethanol , Lysine/metabolism , Sirtuin 1/metabolism , Acetylation , Protein Processing, Post-Translational , Inflammation
9.
Biomedicines ; 11(6)2023 Jun 07.
Article in English | MEDLINE | ID: mdl-37371755

ABSTRACT

Gastrointestinal (GI) complications, including motility disorders, metabolic deficiencies, and changes in gut microbiota following spinal cord injury (SCI), are associated with poor outcomes. After SCI, the autonomic nervous system becomes unbalanced below the level of injury and can lead to severe GI dysfunction. The SmartPill™ is a non-invasive capsule that, when ingested, transmits pH, temperature, and pressure readings that can be used to assess effects in GI function post-injury. Our minipig model allows us to assess these post-injury changes to optimize interventions and ultimately improve GI function. The aim of this study was to compare pre-injury to post-injury transit times, pH, and pressures in sections of GI tract by utilizing the SmartPill™ in three pigs after SCI at 2 and 6 weeks. Tributyrin was administered to two pigs to assess the influences on their gut microenvironment. We observed prolonged GET (Gastric Emptying Time) and CTT (Colon Transit Time), decreases in contraction frequencies (Con freq) in the antrum of the stomach, colon, and decreases in duodenal pressures post-injury. We noted increases in Sum amp generated at 2 weeks post-injury in the colon, with corresponding decreases in Con freq. We found transient changes in pH in the colon and small intestine at 2 weeks post-injury, with minimal effect on stomach pH post-injury. Prolonged GETs and CTTs can influence the absorptive profile in the gut and contribute to pathology development. This is the first pilot study to administer the SmartPill™ in minipigs in the context of SCI. Further investigations will elucidate these trends and characterize post-SCI GI function.

10.
Alcohol Clin Exp Res ; 36(5): 835-46, 2012 May.
Article in English | MEDLINE | ID: mdl-22150547

ABSTRACT

BACKGROUND: Interactions between the gut, immune system, and the liver, as well as the type of fat in the diet, are critical components of alcoholic liver disease (ALD). The goal of the present study was to determine the effects of saturated fat (SF) and unsaturated fat (USF) on ethanol (EtOH)-induced gut-liver interactions in a mouse model of ALD. METHODS: C57BL/6N mice were fed Lieber-DeCarli liquid diets containing EtOH and enriched in USF (corn oil) or SF (medium chain triglycerides:beef tallow). Control mice were pair-fed on an isocaloric basis. Liver injury and steatosis, blood endotoxin levels, intestinal permeability, and tight junction (TJ) integrity, as well as hepatic Toll-like receptor (TLR) gene expression, were evaluated. RESULTS: After 8 weeks of EtOH feeding, liver injury and steatosis were observed in USF + EtOH group compared with control and SF + EtOH. Significantly increased intestinal permeability in conjunction with elevated blood endotoxin levels were observed in the ileal segments of the mice fed USF + EtOH. USF diet alone resulted in down-regulation of intestinal TJ protein mRNA expression compared with SF. Importantly, alcohol further suppressed TJ proteins in USF + EtOH, but did not affect intestinal TJ in SF + EtOH group. The type of fat in the diet alone did not affect hepatic TLR expression. Compared with control animals, hepatic TLR (TLR 1, 2, 3, 4, 7, 8, 9) mRNA expression was significantly (p < 0.05) increased in USF + EtOH, but not in SF + EtOH group. Notably, TLR5 was the only up-regulated TLR in both SF + EtOH and USF + EtOH groups. CONCLUSIONS: Dietary fat is an important cofactor in alcohol-associated liver injury. We demonstrate that USF (corn oil/linoleic acid) by itself results in dysregulation of intestinal TJ integrity leading to increased gut permeability, and alcohol further exacerbates these alterations. We postulate that elevated blood endotoxin levels in response to USF and alcohol in conjunction with up-regulation of hepatic TLRs combine to cause hepatic injury in ALD.


Subject(s)
Dietary Fats, Unsaturated/adverse effects , Gastrointestinal Tract/drug effects , Liver Diseases, Alcoholic/etiology , Tight Junctions/drug effects , Toll-Like Receptors/metabolism , Animals , Body Composition/drug effects , Body Weight/drug effects , Disease Models, Animal , Eating/drug effects , Endotoxins/blood , Ethanol/toxicity , Gastrointestinal Tract/metabolism , Liver/drug effects , Liver/immunology , Liver/metabolism , Liver Diseases, Alcoholic/metabolism , Macrophages/drug effects , Male , Mice , Mice, Inbred C57BL , Oxidative Stress/drug effects , Permeability/drug effects , Up-Regulation/drug effects
11.
Alcohol Clin Exp Res ; 35(5): 815-20, 2011 May.
Article in English | MEDLINE | ID: mdl-21284673

ABSTRACT

Malnutrition, both protein energy malnutrition (PEM) and deficiencies in individual nutrients, is a frequent complication of alcoholic liver disease (ALD). Severity of malnutrition correlates with severity of ALD. Malnutrition also occurs in patients with cirrhosis due to etiologies other than alcohol. The mechanisms for malnutrition are multifactorial, and malnutrition frequently worsens in the hospital due to fasting for procedures and metabolic complications of liver disease, such as hepatic encephalopathy. Aggressive nutritional support is indicated in inpatients with ALD, and patients often need to be fed through an enteral feeding tube to achieve protein and calorie goals. Enteral nutritional support clearly improves nutrition status and may improve clinical outcome. Moreover, late-night snacks in outpatient cirrhotics improve nutritional status and lean body mass. Thus, with no FDA-approved therapy for ALD, careful nutritional intervention should be considered as frontline therapy.


Subject(s)
Liver Diseases, Alcoholic/complications , Liver Diseases, Alcoholic/metabolism , Malnutrition/complications , Malnutrition/metabolism , Animals , Energy Intake/physiology , Humans , Liver Diseases, Alcoholic/therapy , Malnutrition/therapy , Nutritional Status/physiology , Nutritional Support/methods
12.
JCI Insight ; 6(9)2021 05 10.
Article in English | MEDLINE | ID: mdl-33986193

ABSTRACT

SARS coronavirus 2 (SARS-CoV-2) is a novel viral pathogen that causes a clinical disease called coronavirus disease 2019 (COVID-19). Although most COVID-19 cases are asymptomatic or involve mild upper respiratory tract symptoms, a significant number of patients develop severe or critical disease. Patients with severe COVID-19 commonly present with viral pneumonia that may progress to life-threatening acute respiratory distress syndrome (ARDS). Patients with COVID-19 are also predisposed to venous and arterial thromboses that are associated with a poorer prognosis. The present study identified the emergence of a low-density inflammatory neutrophil (LDN) population expressing intermediate levels of CD16 (CD16Int) in patients with COVID-19. These cells demonstrated proinflammatory gene signatures, activated platelets, spontaneously formed neutrophil extracellular traps, and enhanced phagocytic capacity and cytokine production. Strikingly, CD16Int neutrophils were also the major immune cells within the bronchoalveolar lavage fluid, exhibiting increased CXCR3 but loss of CD44 and CD38 expression. The percentage of circulating CD16Int LDNs was associated with D-dimer, ferritin, and systemic IL-6 and TNF-α levels and changed over time with altered disease status. Our data suggest that the CD16Int LDN subset contributes to COVID-19-associated coagulopathy, systemic inflammation, and ARDS. The frequency of that LDN subset in the circulation could serve as an adjunct clinical marker to monitor disease status and progression.


Subject(s)
Blood Coagulation Disorders/blood , Blood Coagulation Disorders/etiology , COVID-19/blood , COVID-19/complications , Neutrophils/immunology , SARS-CoV-2 , Adult , Aged , Aged, 80 and over , Biomarkers/blood , Blood Coagulation Disorders/immunology , COVID-19/immunology , Cytokines/blood , Female , GPI-Linked Proteins/blood , Hospitalization , Humans , Inflammation Mediators/blood , Male , Middle Aged , Neutrophils/classification , Pandemics , Phagocytosis , Platelet Activation , Receptors, IgG/blood , Respiratory Distress Syndrome/blood , Respiratory Distress Syndrome/etiology , Respiratory Distress Syndrome/immunology , Severity of Illness Index
13.
Toxicol Rep ; 7: 1319-1330, 2020.
Article in English | MEDLINE | ID: mdl-33083237

ABSTRACT

Recent reports suggest that arylamine N-acetyltransferases (NAT1 and/or NAT2) serve important roles in regulation of energy utility and insulin sensitivity. We investigated the interaction between diet (control vs. high-fat diet) and acetylator phenotype (rapid vs. slow) using previously established congenic rat lines (in F344 background) that exhibit rapid or slow Nat2 (orthologous to human NAT1) acetylator genotypes. Male and female rats of each genotype were fed control or high-fat (Western-style) diet for 26 weeks. We then examined diet- and acetylator genotype-dependent changes in body and liver weights, systemic glucose tolerance, insulin sensitivity, and plasma lipid profile. Male and female rats on the high fat diet weighed approximately 10% more than rats on the control diet and the percentage liver to body weight was consistently higher in rapid than slow acetylator rats. Rapid acetylator rats were more prone to develop dyslipidemia overall (i.e., higher triglyceride; higher LDL; and lower HDL), compared to slow acetylator rats. Total cholesterol (TC)-to-HDL ratios were significantly higher and HDL-to-LDL ratios were significantly lower in rapid acetylator rats. Our data suggest that rats with rapid systemic Nat2 (NAT1 in humans) genotype exhibited higher dyslipidemia conferring risk for metabolic syndrome and cardiovascular dysfunction.

14.
AIDS Res Hum Retroviruses ; 35(1): 92-99, 2019 01.
Article in English | MEDLINE | ID: mdl-30280905

ABSTRACT

Heavy alcohol drinking causes alterations in the metabolism of fatty acids and zinc that participate in inflammation and liver injury. HIV infection has been reported to cause dysregulated polyunsaturated fatty acid (PUFA) and zinc metabolism. In this pilot study, we examined the role of dysregulated PUFA metabolism and zinc deficiency in the liver injury occurring in heavy drinkers with early-stage HIV diagnosis. Fourteen heavy drinking alcohol-dependent (AD) patients [seven with treatment-naive HIV diagnosis (AD+HIV) and seven without HIV infection (AD)] participated in this study. Liver injury, serum zinc, PUFAs, viral load, CD4+ count, and drinking measures using lifetime drinking history (LTDH), and timeline follow-back past 90 days (TLFB90) were evaluated. Liver injury was also assessed in seven age- and gender-matched socially drinking HIV treatment-naive patients who served as disease controls. HIV viral load by itself did not show any correlation with liver injury. Liver enzymes were significantly elevated in both AD+HIV and AD patients, and AD+HIV patients had significantly higher alanine aminotransferase (ALT) levels than did AD patients, even with lower drinking. Serum zinc was significantly lower in AD+HIV patients. Only AD+HIV patients showed a significant elevation in linoleic acid (LA) and alpha-linoleic acid (ALA) levels. Serum zinc and ALT, LA and ALT, and ALA and ALT were significantly associated only in AD+HIV patients. The association between LA and ALT showed a higher effect than did the ALA and ALT association in the AD+HIV patients. Interestingly, AD+HIV subjects (who drank less), nevertheless, showed more liver injury compared with AD patients, who reported heavier drinking. We speculate that the underlying proinflammatory response resulting from zinc deficiency and an elevation in serum LA likely contributed to liver injury in AD+HIV patients, even with a comparatively lower degree of heavy drinking.


Subject(s)
Alcoholism/complications , Chemical and Drug Induced Liver Injury/pathology , Fatty Acids, Unsaturated/blood , HIV Infections/complications , Zinc/blood , Adult , Aged , Female , Humans , Male , Middle Aged , Pilot Projects , Serum/chemistry , Young Adult
15.
Open Forum Infect Dis ; 6(6): ofz188, 2019 Jun.
Article in English | MEDLINE | ID: mdl-31211153

ABSTRACT

BACKGROUND: The prevalence and risk of concurrent unhealthy drinking, cigarette use, and depression on mortality among persons living with HIV (PLWH) is unclear. This study applied a syndemic framework to assess whether these co-occurring conditions increase mortality and whether such risk is differential by HIV status. METHODS: We evaluated 6721 participants (49.8% PLWH) without baseline cancer from the Veterans Aging Cohort Study, a prospective, observational cohort of PLWH and matched uninfected veterans enrolled in 2002 and followed through 2015. Multivariable Cox proportional hazards regressions estimated risk of a syndemic score (number of conditions: that is, unhealthy drinking, cigarette use, and depressive symptoms) on all-cause mortality by HIV status, adjusting for demographic, health status, and HIV-related factors. RESULTS: Fewer than 10% of participants had no conditions; 25.6% had 1, 51.0% had 2, and 15.0% had all 3. There were 1747 deaths (61.9% PLWH) during the median follow-up (11.4 years). Overall, age-adjusted mortality rates/1000 person-years increased with a greater number of conditions: (0: 12.0; 1: 21.2; 2: 30.4; 3: 36.3). For 3 conditions, the adjusted hazard ratio of mortality was 36% higher among PLWH compared with uninfected participants with 3 conditions (95% confidence interval, 1.07-1.72; P = .013), after adjusting for health status and HIV disease progression. Among PLWH and uninfected participants, mortality risk persisted after adjustment for time-updated health status. CONCLUSIONS: Syndemic unhealthy drinking, cigarette use, and depression are common and are associated with higher mortality risk among PLWH, underscoring the need to screen for and treat these conditions.

16.
J Nutr Biochem ; 19(3): 184-92, 2008 Mar.
Article in English | MEDLINE | ID: mdl-17618106

ABSTRACT

4-Hydroxy-2-nonenal (HNE), the aldehydic product of lipid peroxidation, is associated with multiple immune dysfunctions, such as HIV and hepatitis C virus infection. HNE-induced immunosuppression could be due to a decrease in CD4+ T lymphocyte activation or proliferation. Glutathione (GSH) is the most abundant endogenous antioxidant in cells, and an adduct between HNE and GSH has been suggested to be a marker of oxidative stress. Our earlier studies showed that HNE induced cytotoxicity and Akt inactivation, which led to the enhancement of FasL expression and concomitantly decreased cellular FLICE-like inhibitory protein (c-FLIP(S)) levels. In this study, we found that HNE caused intracellular GSH depletion in Jurkat T cells, and we further investigated the role of 2(RS)-n-propylthiazolidine-4(R)-carboxylic acid (PTCA), a GSH prodrug, in attenuating HNE-induced cytotoxicity in CD4+ T lymphocytes. The results show that PTCA protected against HNE-induced apoptosis and depletion of intracellular GSH. PTCA also suppressed FasL expression through increasing levels of Akt kinase as well as antiapoptotic c-FLIP(S) and decreasing the activation of type 2 protein serine/threonine phosphatase. Taken together, these data demonstrate a novel correlation between GSH levels and Akt activation in T lymphocyte survival, which involves FasL down-regulation and c-FLIP(S) expression through increasing intracellular GSH levels. This suggests that PTCA could potentially be used in the treatment of oxidative stress-induced immunosuppressive diseases.


Subject(s)
Aldehydes/pharmacology , Apoptosis/drug effects , CD4-Positive T-Lymphocytes/drug effects , Thiazoles/pharmacology , CASP8 and FADD-Like Apoptosis Regulating Protein/analysis , CD4-Positive T-Lymphocytes/chemistry , CD4-Positive T-Lymphocytes/cytology , Enzyme Activation/drug effects , Fas Ligand Protein/genetics , Glutathione/analysis , Humans , Jurkat Cells , Protein Phosphatase 2/metabolism , Proto-Oncogene Proteins c-akt/metabolism , RNA, Messenger/analysis , Signal Transduction/drug effects , fas Receptor/physiology
17.
J Nutr Biochem ; 19(6): 384-91, 2008 Jun.
Article in English | MEDLINE | ID: mdl-17869084

ABSTRACT

An important aspect in alcohol abuse-associated immune suppression is the loss of T helper CD4(+) lymphocytes, leading to impairment of multiple immune functions. Our work has shown that ethanol can sensitize CD4(+) T lymphocytes to caspase-3-dependent activation-induced cell death (AICD). It has been demonstrated that the formation of S-adenosylmethionine (SAMe) catalyzed by methionine adenosyltransferase (MAT) II is essential for CD4(+) T-cell activation and proliferation. Since ethanol is known to affect SAMe metabolism in hepatocytes, we investigated the effect of ethanol on MAT II activity/expression, SAMe biosynthesis and cell survival in CD4(+) T lymphocytes. We demonstrate for the first time that ethanol at a physiologically relevant concentration (25 mM) substantially decreased the enzymatic activity of MAT II in T lymphocytes. Ethanol was observed to decrease the transcription of MAT2A, which encodes the catalytic subunit of MAT II and is vital for MAT II activity and SAMe biosynthesis. Furthermore, correspondent to its effect on MAT II, ethanol decreased intracellular SAMe levels and enhanced caspase-3-dependent AICD. Importantly, restoration of intracellular SAMe levels by exogenous SAMe supplementation considerably decreased both caspase-3 activity and apoptotic death in T lymphocytes. In conclusion, our data show that MAT II and SAMe are critical molecular components essential for CD4(+) T-cell survival that are affected by ethanol, leading to enhanced AICD. Furthermore, these studies provide a clinical paradigm for the development of much needed therapy using SAMe supplementation in the treatment of immune dysfunction induced by alcohol abuse.


Subject(s)
Apoptosis/drug effects , CD4-Positive T-Lymphocytes/drug effects , Caspase 3/physiology , Ethanol/pharmacology , Immune Tolerance/drug effects , Methionine Adenosyltransferase/antagonists & inhibitors , S-Adenosylmethionine/antagonists & inhibitors , Caspase 3/drug effects , Humans , Jurkat Cells , RNA, Messenger/metabolism , S-Adenosylmethionine/biosynthesis , S-Adenosylmethionine/pharmacology
18.
Mol Cancer Ther ; 5(7): 1790-9, 2006 Jul.
Article in English | MEDLINE | ID: mdl-16891465

ABSTRACT

AGRO100, also known as AS1411, is an experimental anticancer drug that recently entered human clinical trials. It is a member of a novel class of antiproliferative agents known as G-rich oligonucleotides (GRO), which are non-antisense, guanosine-rich phosphodiester oligodeoxynucleotides that form stable G-quadruplex structures. The biological activity of GROs results from their binding to specific cellular proteins as aptamers. One important target protein of GROs has been previously identified as nucleolin, a multifunctional protein expressed at high levels by cancer cells. Here, we report that AGRO100 also associates with nuclear factor-kappaB (NF-kappaB) essential modulator (NEMO), which is a regulatory subunit of the inhibitor of kappaB (IkappaB) kinase (IKK) complex, and also called IKKgamma. In the classic NF-kappaB pathway, the IKK complex is required for phosphorylation of IkappaBalpha and subsequent activation of the transcription factor NF-kappaB. We found that treatment of cancer cells with AGRO100 inhibits IKK activity and reduces phosphorylation of IkappaBalpha in response to tumor necrosis factor-alpha stimulation. Using a reporter gene assay, we showed that AGRO100 blocks both tumor necrosis factor-alpha-induced and constitutive NF-kappaB activity in human cancer cell lines derived from cervical, prostate, breast, and lung carcinomas. In addition, we showed that, in AGRO100-treated cancer cells, NEMO is coprecipitated by nucleolin, indicating that both proteins are present in the same complex. Our studies suggest that abrogation of NF-kappaB activity may contribute to the anticancer effects of AGRO100 and that nucleolin may play a previously unknown role in regulating the NF-kappaB pathway.


Subject(s)
Antineoplastic Agents/pharmacology , Aptamers, Nucleotide/pharmacology , I-kappa B Kinase/metabolism , NF-kappa B/antagonists & inhibitors , Oligodeoxyribonucleotides/pharmacology , Phosphoproteins/metabolism , RNA-Binding Proteins/metabolism , Antineoplastic Agents/metabolism , Antineoplastic Agents/therapeutic use , Aptamers, Nucleotide/metabolism , Aptamers, Nucleotide/therapeutic use , Cell Line, Tumor , Female , Genes, Reporter/drug effects , Humans , I-kappa B Kinase/antagonists & inhibitors , Immunoprecipitation , Male , NF-kappa B/agonists , NF-kappa B/metabolism , Neoplasms/drug therapy , Neoplasms/genetics , Oligodeoxyribonucleotides/metabolism , Oligodeoxyribonucleotides/therapeutic use , Phosphorylation/drug effects , Nucleolin
19.
J Biosci Med (Irvine) ; 4(7): 23-27, 2016 Jul.
Article in English | MEDLINE | ID: mdl-27489857

ABSTRACT

HIV and HCV co-infection is a unique disease condition, and medical management of such condition is difficult due to severity and systemic complications. Added with heavy alcohol drinking, risk of liver injury increases due to several pro-inflammatory responses that subsequently get involved with alcohol metabolism. Elevated levels of fatty acids have been reported both in viral infections as well as alcoholic liver disease though such investigations have not addressed the adverse events with dual viral infection of HIV and HCV along with heavy drinking. This case report is of a patient with excessive alcohol drinking and first time diagnosis of HIV and HCV dual infection, elaborating concurrent alteration in Linoleic Acid (LA) levels and pro-inflammatory shift in ω-6/ω-3 ratio along with the elevations in liver injury markers. Elevated LA has been recently studied extensively for its role in alcoholic liver disease; and in the present case, we also found it to be clinically relevant to liver injury.

20.
Article in English | MEDLINE | ID: mdl-27275009

ABSTRACT

BACKGROUND AND AIM: Liver injury is estimated by serum alanine aminotransferases (ALT) levels in experimental animal models. Laboratories use various techniques to measure ALT levels including assay reagents and chemistry analyzers. VetScan VS2 (VS2) is widely used in veterinary clinics and research laboratories for highly reproducible, convenient and effective testing. Alternatively, ALT liquid reagent is used by laboratories to estimate liver injury in animal studies. The aim of this study was to perform comparative analyses of data obtained from these two assays in two different animal models. METHODS: In this study, we used two different mouse models and compared the ALT levels measured using VetScan VS2 chemistry analyzer and ALT liquid reagent. Immunohistochemical analysis of hepatic tissue was also performed to document liver pathology. The first model is a high fat diet feeding model that results in a mild hepatic steatosis (fat accumulation in the liver) without elevation of ALT levels. For a severe liver injury model, we employed a hepatotoxin-induced liver injury model (carbon tetrachloride, CCl4), which leads to the development of hepatic fibrosis and very high ALT levels. RESULTS: VetScan VS2 and ALT reagent gave different values of ALT for all animal groups. However, linear regression analysis showed a significantly high association between ALT levels obtained by VS2 and ALT liquid reagent in a high-fat feeding model with no liver injury. For the CCl4 induced liver injury model, serum dilution (5 and 10 times) was performed to obtain accurate results with ALT reagent. ALT levels acquired from both techniques showed a close association. Interestingly, this correlation was closer when serum was diluted 5 fold. CONCLUSION: This study demonstrates that both methods give similar results when evaluating liver injury in animal studies. However, the serum dilution factor is critical for severe liver injury assessment when using ALT reagent and requires some optimization. In this regard, VetScan VS2 is easier to use and gives comparable results.

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