40 research outputs found
Computed tomography measures of nutrition in patients with end-stage liver disease provide a novel approach to characterize deficits
Aim
Patients with cirrhosis and end-stage liver disease (ESLD) develop severe nutrition deficits that impact on morbidity and mortality. Laboratory measures of nutrition fail to fully assess clinical deficits in muscle mass and fat stores. This study employs computed tomography imaging to assess muscle mass and subcutaneous and visceral fat stores in patients with ESLD.
Methods
This 1:1 case-control study design compares ESLD patients with healthy controls. Study patients were selected from a database of ESLD patients using a stratified method to assure a representative sample based on age, body mass index (BMI), gender, and model for end-stage liver disease score (MELD). Control patients were trauma patients with a low injury severity score (<10) who had a CT scan during evaluation. Cases and controls were matched for age +/- 5 years, gender, and BMI +/- 2.
Results
There were 90 subjects and 90 controls. ESLD patients had lower albumin levels (p<0.001), but similar total protein levels (p=0.72). ESLD patients had a deficit in muscle mass (-19%, p<0.001) and visceral fat (-13%, p<0.001), but similar subcutaneous fat (-1%, p=0.35). ESLD patients at highest risk for sarcopenia included those over age 60, BMI< 25.0, and female gender. We found degree of sarcopenia to be independent of MELD score.
Conclusions
These results support previous research demonstrating substantial nutrition deficits in ESLD patients that are not adequately measured by laboratory testing. Patients with ESLD have significant deficits of muscle and visceral fat stores, but a similar amount of subcutaneous fat
Bile Acids Conjugation in Human Bile Is Not Random: New Insights from 1H-NMR Spectroscopy at 800 MHz
Bile acids constitute a group of structurally closely related molecules and represent the most abundant constituents of human bile. Investigations of bile acids have garnered increased interest owing to their recently discovered additional biological functions including their role as signaling molecules that govern glucose, fat and energy metabolism. Recent NMR methodological developments have enabled single-step analysis of several highly abundant and common glycine- and taurine- conjugated bile acids, such as glycocholic acid, glycodeoxycholic acid, glycochenodeoxycholic acid, taurocholic acid, taurodeoxycholic acid, and taurochenodeoxycholic acid. Investigation of these conjugated bile acids in human bile employing high field (800 MHz) (1)H-NMR spectroscopy reveals that the ratios between two glycine-conjugated bile acids and their taurine counterparts correlate positively (R2 = 0.83-0.97; p = 0.001 x 10(-2)-0.006 x 10(-7)) as do the ratios between a glycine-conjugated bile acid and its taurine counterpart (R2 = 0.92-0.95; p = 0.004 x 10(-3)-0.002 x 10(-10)). Using such correlations, concentration of individual bile acids in each sample could be predicted in good agreement with the experimentally determined values. These insights into the pattern of bile acid conjugation in human bile between glycine and taurine promise useful clues to the mechanism of bile acids' biosynthesis, conjugation and enterohepatic circulation, and may improve our understanding of the role of individual conjugated bile acids in health and disease
Thalidomide ameliorates portal hypertension via nitric oxide synthase independent reduced systolic blood pressure
AIM: Portal hypertension is a common complication of liver cirrhosis and significantly increases mortality and morbidity. Previous reports have suggested that the compound thalidomide attenuates portal hypertension (PHT). However, the mechanism for this action is not fully elucidated. One hypothesis is that thalidomide destabilizes tumor necrosis factor α (TNFα) mRNA and therefore diminishes TNFα induction of nitric oxide synthase (NOS) and the production of nitric oxide (NO). To examine this hypothesis, we utilized the murine partial portal vein ligation (PVL) PHT model in combination with endothelial or inducible NOS isoform gene knockout mice.
METHODS: Wild type, inducible nitric oxide synthase (iNOS)-/- and endothelial nitric oxide synthase (eNOS)-/- mice received either PVL or sham surgery and were given either thalidomide or vehicle. Serum nitrate (total nitrate, NOx) was measured daily for 7 d as a surrogate of NO synthesis. Serum TNFα level was quantified by enzyme-linked immunosorbent assay. TNFα mRNA was quantified in liver and aorta tissue by reverse transcription-polymerase chain reaction. PHT was determined by recording splenic pulp pressure (SPP) and abdominal aortic flow after 0-7 d. Response to thalidomide was determined by measurement of SPP and mean arterial pressure (MAP).
RESULTS: SPP, abdominal aortic flow (Qao) and plasma NOx were increased in wild type and iNOS-/- PVL mice when compared to sham operated control mice. In contrast, SPP, Qao and plasma NOx were not increased in eNOS-/- PVL mice when compared to sham controls. Serum TNFα level in both sham and PVL mice was below the detection limit of the commercial ELISA used. Therefore, the effect of thalidomide on serum TNFα levels was undetermined in wild type, eNOS-/- or iNOS-/- mice. Thalidomide acutely increased plasma NOx in wild type and eNOS-/- mice but not iNOS-/- mice. Moreover, thalidomide temporarily (0-90 min) decreased mean arterial pressure, SPP and Qao in wild type, eNOS-/- and iNOS-/- PVL mice, after which time levels returned to the respective baseline.
CONCLUSION: Thalidomide does not reduce portal pressure in the murine PVL model by modulation of NO biosynthesis. Rather, thalidomide reduces PHT by decreasing MAP by an undetermined mechanism
Metabolomic Characterization of Human Model of Liver Rejection Identifies Aberrancies Linked to Cyclooxygenase (COX) and Nitric Oxide Synthase (NOS)
BACKGROUND Acute liver rejection (ALR), a significant complication of liver transplantation, burdens patients, healthcare payers, and the healthcare providers due to an increase in morbidity, cost, and resources. Despite clinical resolution, ALR is associated with an increased risk of graft loss. A unique protocol of delayed immunosuppression used in our institute provided a model to characterize metabolomic profiles in human ALR. MATERIAL AND METHODS Twenty liver allograft biopsies obtained 48 hours after liver transplantation in the absence of immunosuppression were studied. Hepatic metabolites were quantitated in these biopsies by liquid chromatography and mass spectroscopy (LC/MS). Metabolite profiles were compared among: 1) biopsies with reperfusion injury but no histological evidence of rejection (n=7), 2) biopsies with histological evidence of moderate or severe rejection (n=5), and 3) biopsies with histological evidence of mild rejection (n=8). RESULTS There were 133 metabolites consistently detected by LC/MS and these were prioritized using variable importance to projection (VIP) analysis, comparing moderate or severe rejection vs. no rejection or mild rejection using partial least squares discriminant statistical analysis (PLS-DA). Twenty metabolites were identified as progressively different. Further PLS-DA using these metabolites identified 3 metabolites (linoleic acid, γ-linolenic acid, and citrulline) which are associated with either cyclooxygenase or nitric oxide synthase functionality. CONCLUSIONS Hepatic metabolic aberrancies associated with cyclooxygenase and nitric oxide synthase function occur contemporaneous with ALR. Additional studies are required to better characterize the role of these metabolic pathways to enhance utility of the metabolomics approach in diagnosis and outcomes of ALR
Antithymocyte Globulin Antibody Titer Congruent With Kidney Transplantation: Analysis of Incidence, Outcomes, Cost, and Alternative Targets
Rabbit antithymocyte globulin (rATG) use for immunosuppression induction is widespread but is contraindicated by the presence of anti-rATG antibodies. This study reports the incidence of positive anti-rATG antibody titers in patients before and after renal transplant and evaluates associated outcomes and costs. In addition, it will correlate CD40L and interleukin (IL)-21 with anti-rATG antibody titers.
Methods:
Clinical and billing records from the Indiana University Transplant Laboratory were reviewed for positive versus negative anti-rATG antibody titers, graft survival, and 7-day readmission costs between 2004 and 2018. Serum from patients with positive and negative rATG antibody titers were quantitated for CD40L and IL-21 by enzyme-linked immunosorbent assay.
Results:
On average, between 2004 and May 2018, 163 kidney transplants per year were performed. Anti-rATG antibody titers were ordered for 17 patients/year, of which 18.2% were positive at 1:100 titer either pre- or post-transplant. Time to graft loss correlated with a positive rATG titer at time of readmission. Moreover, second kidney transplant increased the anti-rATG positive rate. A weak correlation was observed between anti-rATG titer and recipient age. Seven-day readmission treatment costs were significantly lower in patients with positive anti-rATG titer. IL-21 and CD40L were significantly greater in patients with positive anti-rATG titers after transplant when compared with negative anti rATG patients.
Conclusions:
Positive anti-rATG antibody titer is associated with a significant negative impact on outcomes. Monitoring of anti-rATG antibody titer is recommended to optimize treatment options in patients, especially in the setting of second transplants. Elucidation of the mechanisms associated with positive anti-rATG antibody is required. IL-21 and CD40L are potential targets for future study
Autotaxin expression and its connection with the TNF-alpha-NF-κB axis in human hepatocellular carcinoma
<p>Abstract</p> <p>Background</p> <p>Autotaxin (ATX) is an extracellular lysophospholipase D that generates lysophosphatidic acid (LPA) from lysophosphatidylcholine (LPC). Both ATX and LPA have been shown to be involved in many cancers. However, the functional role of ATX and the regulation of ATX expression in human hepatocellular carcinoma (HCC) remain elusive.</p> <p>Results</p> <p>In this study, ATX expression was evaluated in tissues from 38 human HCC and 10 normal control subjects. ATX was detected mainly in tumor cells within tissue sections and its over-expression in HCC was specifically correlated with inflammation and liver cirrhosis. In addition, ATX expression was examined in normal human hepatocytes and liver cancer cell lines. Hepatoma Hep3B and Huh7 cells displayed stronger ATX expression than hepatoblastoma HepG2 cells and normal hepatocytes did. Proinflammtory cytokine tumor necrosis factor alpha (TNF-α) promoted ATX expression and secretion selectively in Hep3B and Huh7 cells, which led to a corresponding increase in lysophospholipase-D activity. Moreover, we explored the mechanism governing the expression of ATX in hepatoma cells and established a critical role of nuclear factor-kappa B (NF-κB) in basal and TNF-α induced ATX expression. Further study showed that secreted enzymatically active ATX stimulated Hep3B cell invasion.</p> <p>Conclusions</p> <p>This report highlights for the first time the clinical and biological evidence for the involvement of ATX in human HCC. Our observation that links the TNF-α/NF-κB axis and the ATX-LPA signaling pathway suggests that ATX is likely playing an important role in inflammation related liver tumorigenesis.</p
Evaluation of 11C-Acetate and 18 F-FDG PET/CT in mouse multidrug resistance gene-2 deficient mouse model of hepatocellular carcinoma
Background
Hepatocellular carcinoma (HCC) remains a global health problem with unique diagnostic and therapeutic challenges, including difficulties in identifying the highest risk patients. Previous work from our lab has established the murine multidrug resistance-2 mouse (MDR2) model of HCC as a reasonable preclinical model that parallels the changes seen in human inflammatory associated HCC. The purpose of this study is to evaluate modalities of PET/CT in MDR2−/− mice in order to facilitate therapeutic translational studies from bench to bedside.
Methods
18F-FDG and 11C-acetate PET/CT was performed on 12 m MDR2−/− mice (n = 3/tracer) with HCC and 12 m MDR2−/+ control mice (n = 3/tracer) without HCC. To compare PET/CT to biological markers of HCC and cellular function, serum alpha-fetoprotein (AFP), lysophosphatidic acid (LPA), cAMP and hepatic tumor necrosis factor α (TNFα) were quantified in 3-12 m MDR2−/− (n = 10) mice using commercially available ELISA analysis. To translate results in mice to patients 11C-acetate PET/CT was also performed in 8 patents suspected of HCC recurrence following treatment and currently on the liver transplant wait list.
Results
Hepatic18F-FDG metabolism was not significantly increased in MDR2−/− mice. In contrast, hepatic 11C-acetate metabolism was significantly elevated in MDR2−/− mice when compared to MDR2−/+ controls. Serum AFP and LPA levels increased in MDR2−/− mice contemporaneous with the emergence of HCC. This was accompanied by a significant decrease in serum cAMP levels and an increase in hepatic TNFα. In patients suspected of HCC recurrence there were 5 true positives, 2 true negatives and 1 suspected false 11C-acetate negative.
Conclusions
Hepatic 11C-acetate PET/CT tracks well with HCC in MDR2−/− mice and patients with underlying liver disease. Consequently 11C-acetate PET/CT is well suited to study 1) HCC emergence/progression in patients and 2) reduce animal numbers required to study new chemotherapeutics in murine models of HCC
Specialized care improves outcomes for patients with cirrhosis who require general surgical operations
BACKGROUND:
General surgical operations on patients with cirrhosis have historically been associated with high morbidity and mortality rates. This study examines a contemporary series of patients with cirrhosis undergoing general surgical procedures.
METHODS:
A retrospective evaluation of 358 cirrhotic patients undergoing general surgical operations at a single institution between 2004-2015 was performed. Thirty- and 90-day mortality along with complications and subsequent transplantation rates were examined.
RESULTS:
358 cirrhotic patients were identified. The majority were Child-Turcotte-Pugh class (CTP) A (55.9%) followed by class B (32.4%) and class C (11.7%). Mean MELD score differed significantly between the groups (8.7 vs. 12.1 vs. 20.1; p<0.001). The most common operations were herniorrhaphy (29.9%), cholecystectomy (19.3%), and liver resection (14.5%). The majority of cases were performed semi-electively (68.4%), however, within the CTP C patients most cases were performed emergently (73.8%). Thirty and 90-day mortality for all patients were 5% and 6%, respectively. Mortality rates increased from CTP A to CTP C (30 day: 3.0% vs. 5.2% vs. 14.3%; p = 0.01; 90 day: 4.5% vs. 6.9% vs. 16.7%; p = 0.016). Additionally, 30-day mortality (12.8% vs. 2.3%; p<0.001), 90 day mortality (16.0% vs. 3.4%; p<0.001) were higher for emergent compared to elective cases. A total of 13 (3.6%) patients underwent transplantation ≤ 90 days from surgery. No elective cases resulted in an urgent transplantation.
CONCLUSION:
Performing general surgical operations on cirrhotic patients carries a significant morbidity and mortality. This contemporary series from a specialized liver center demonstrates improved outcomes compared to historical series. These data strongly support early referral of cirrhotic patients needing general surgical operation to centers with liver expertise to minimize morbidity and mortality
Cross-Sectional and Longitudinal Associations between Household Food Security and Child Anthropometry at Ages 5 and 8 Years in Ethiopia, India, Peru, and Vietnam
En: Journal of Nutrition, No. 145, pp. 1924-1933. doi:10.3945/jn.115.210229Background: Poor childhood nutritional status has lifetime effects and food insecurity is associated with dietary practices that can impair nutritional status. Objectives: We assessed concurrent and subsequent associations between food insecurity and height-for-age z scores (HAZs) and body mass index–for-age z scores (BMI-Zs); evaluated associations with transitory and chronic food insecurity; and tested whether dietary diversity mediates associations between food insecurity and nutritional status. Methods: We used data from the Young Lives younger cohort composed of children in Ethiopia (n = 1757), India (n =1825), Peru (n = 1844), and Vietnam (n = 1828) recruited in 2002 (round 1) at ;1 y old, with subsequent data collection at 5 y in 2006 (round 2) and 8 y in 2009 (round 3). Results: Children from food-insecure households had significantly lower HAZs in all countries at 5 y (Ethiopia, 20.33; India, 20.53; Peru, 20.31; and Vietnam, 20.68 HAZ; all P < 0.001), although results were attenuated after controlling for potential confounders (Ethiopia, 20.21; India, 20.32; Peru, 20.14; and Vietnam, 20.27 HAZ; P < 0.01). Age 5 y food insecurity predicted the age 8 y HAZ, but did not add predictive power beyond HAZ at age 5 y in Ethiopia, India, or Peru. Age 5 y food insecurity predicted the age 8 y BMI-Z even after controlling for the 5 y BMI-Z, although associations were not significant after the inclusion of additional confounding variables (Ethiopia, P = 0.12; India, P = 0.29; Peru, P = 0.16; and Vietnam, P = 0.51). Chronically food-insecure households had significantly lower HAZs than households that were consistently food-secure, although BMI-Zs did not differ by chronic food-insecurity status. Dietary diversity mediated 18.8–30.5% of the association between food security and anthropometry in Vietnam, but mediated to a lesser degree (8.4–19.3%) in other countries. Conclusions: In 4 countries, food insecurity at 5 y of age was associated with both HAZ and BMI-Z at age 8 y, although the association was attenuated after adjusting for other household factors and anthropometry at age 5 y, and remained significant only for the HAZ in Vietnam