BACKGROUND

Using either an angiotensin-converting enzyme inhibitor (ACEi) or an angiotensin receptor blocker (ARB) the morning of surgery may lead to 'functional' postoperative acute kidney injury (AKI), measured by an abrupt increase in serum creatinine. Whether the same is true for 'structural' AKI, measured with new urinary biomarkers, is unknown.

METHODS

The TRIBE-AKI study was a prospective cohort study of 1594 adults undergoing cardiac surgery at six hospitals between July 2007 and December 2010. We classified the degree of exposure to ACEi/ARB into three categories: 'none' (no exposure prior to surgery), 'held' (on chronic ACEi/ARB but held on the morning of surgery) or 'continued' (on chronic ACEi/ARB and taken the morning of surgery). The co-primary outcomes were 'functional' AKI based upon changes in pre- to postoperative serum creatinine, and 'structural AKI', based upon peak postoperative levels of four urinary biomarkers of kidney injury.

RESULTS

Across the three levels (none, held and continued) of ACEi/ARB exposure there was a graded increase in functional AKI, as defined by AKI stage 1 or worse; (<em>31</em>, 34 and 42%, P for trend 0.03) and by percentage change in serum creatinine from pre- to postoperative (25, 26 and 30%, P for trend 0.03). In contrast, there were no differences in structural AKI across the strata of ACEi/ARB exposure, as assessed by four structural AKI biomarkers (neutrophil gelatinase-associated lipocalin, kidney injury molecule-1, <em>interleukin</em>-18 or liver-fatty acid-binding protein).

CONCLUSIONS

Preoperative ACEi/ARB usage was associated with functional but not structural acute kidney injury. As AKI from ACEi/ARB in this setting is unclear, interventional studies testing different strategies of perioperative ACEi/ARB use are warranted.

BACKGROUND

Delirium is a common occurrence in critically ill patients and is associated with an increase in morbidity and mortality. Septic patients with delirium may differ from a general critically ill population. The aim of this investigation was to study the relationship between systemic inflammation and the development of delirium in septic and non-septic critically ill patients.

METHODS

We performed a prospective cohort study in a 20-bed mixed intensive care unit (ICU) including 78 (delirium = <em>31</em>; non-delirium = 47) consecutive patients admitted for more than 24 hours. At enrollment, patients were allocated to septic or non-septic groups according to internationally agreed criteria. Delirium was diagnosed using the Confusion Assessment Method for the Intensive Care Unit (CAM-ICU) during the first 72 hours of ICU admission. Blood samples were collected within 12 hours of enrollment for determination of tumor necrosis factor (TNF)-α, soluble TNF Receptor (STNFR)-1 and -2, <em>interleukin</em> (IL)-1β, IL-6, IL-10 and adiponectin.

RESULTS

Out of all analyzed biomarkers, only STNFR1 (P = 0.003), STNFR2 (P = 0.005), adiponectin (P = 0.005) and IL-1β (P < 0.001) levels were higher in delirium patients. Adjusting for sepsis and sedation, these biomarkers were also independently associated with delirium occurrence. However, none of them were significant influenced by sepsis.

CONCLUSIONS

STNFR1, STNFR2, adiponectin and IL-1β were associated with delirium. Sepsis did not modify the relationship between the biomarkers and delirium occurrence.

Cardiac fibroblasts (CFs) play a key role in response to injury and remodeling of the heart. Nucleotide (P2) receptors regulate the heart but limited information is available regarding such receptors in CFs. We thus sought to determine if extracellular nucleotides regulate fibrotic responses (e.g., proliferation, migration and expression of profibrotic markers) of CFs in primary culture. UTP increased rat CF migration 3-fold (p<0.001), proliferation by 30% (p<0.05) and mRNA expression of profibrotic markers: alpha smooth muscle actin (alpha-SMA), plasminogen activator inhibitor-1 (PAI-1), transforming growth factor beta, soluble ST2, <em>interleukin</em>-6 and monocyte chemoattractant protein-1 (MCP-1) by 3.0-, 15-, 2.0-, 7.6-, 11-, and 6.1-fold, respectively (p<0.05). PAI-1 protein expression induced by UTP was dependent on protein kinase C (PKC) and extracellular signal-regulated kinase (ERK), based on blockade by the PKC inhibitor Ro-<em>31</em>-8220 and the ERK inhibitor U0126, respectively. The rank order for enhanced expression of PAI-1 and alpha-SMA by nucleotides (UTPgammaS>)UDPbetaS>)ATPgammaS), the expression of P2Y2 receptors as the most abundantly expressed P2Y receptor in rat CFs and a blunted response to UTP in P2Y2(-/-) mice all implicate P2Y2 as the predominant P2Y receptor that mediates nucleotide-promoted profibrotic responses. Additional results indicate that P2Y2 receptor-promoted profibrotic responses in CFs are transient, perhaps as a consequence of receptor desensitization. We conclude that P2Y2 receptor activation is profibrotic in CFs; thus inhibition of P2Y2 receptors may provide a novel means to diminish fibrotic remodeling and turnover of extracellular matrix in the heart.

Necrotizing enterocolitis (NEC) in preterm infants develops very rapidly from a mild intolerance to enteral feeding into intestinal mucosal hemorrhage, inflammation, and necrosis. We hypothesized that immediate feeding-induced gut responses precede later clinical NEC symptoms in preterm pigs. Fifty-six preterm pigs were fed total parenteral nutrition (TPN) for 48 h followed by enteral feeding for 0, 8, 17, or 34 h with either colostrum (Colos, n = 20) or formula (Form, n = <em>31</em>). Macroscopic NEC lesions were detected in Form pigs throughout the enteral feeding period (20/<em>31</em>, 65%), whereas most Colos pigs remained protected (1/20, 5%). Just 8 h of formula feeding induced histopathological lesions, as evidenced by capillary stasis and necrosis, epithelial degeneration, edema, and mucosal hemorrhage. These immediate formula-induced changes were paralleled by decreased digestive enzyme activities (lactase and dipeptidylpeptidase IV), increased nutrient fermentation, and altered expression of innate immune defense genes such as <em>interleukins</em> (IL-1α, IL-6, IL-18), nitric oxide synthetase, tight junction proteins (claudins), Toll-like receptors (TLR-4), and TNF-α. In contrast, the first hours of colostrum feeding induced no histopathological lesions, increased maltase activity, and induced changes in gene expressions related to tissue development. Total bacterial density was high after 2 days of parenteral feeding and was not significantly affected by diet (colostrum, formula) or length of enteral feeding (8-34 h), except that a few bacterial groups (Clostridium, Enterococcus, Streptococcus species) increased with time. We conclude that a switch from parenteral to enteral nutrition rapidly induces diet-dependent histopathological, functional, and proinflammatory insults to the immature intestine. Great care is required when introducing enteral feeds to TPN-fed preterm infants, particularly when using formula, because early feeding-induced insults may predispose to NEC lesions that are difficult to revert by later dietary or medical interventions.

Familial primary localized cutaneous amyloidosis (FPLCA) is an autosomal-dominant disorder associated with chronic skin itching and deposition of epidermal keratin filament-associated amyloid material in the dermis. FPLCA has been mapped to 5p13.1-q11.2, and by candidate gene analysis, we identified missense mutations in the OSMR gene, encoding oncostatin M-specific receptor beta (OSMRbeta), in three families. OSMRbeta is a component of the oncostatin M (OSM) type II receptor and the <em>interleukin</em> (IL)-<em>31</em> receptor, and cultured FPLCA keratinocytes showed reduced activation of Jak/STAT, MAPK, and PI3K/Akt pathways after OSM or IL-<em>31</em> cytokine stimulation. The pathogenic amino acid substitutions are located within the extracellular fibronectin type III-like (FNIII) domains, regions critical for receptor dimerization and function. OSM and IL-<em>31</em> signaling have been implicated in keratinocyte cell proliferation, differentiation, apoptosis, and inflammation, but our OSMR data in individuals with FPLCA represent the first human germline mutations in this cytokine receptor complex and provide new insight into mechanisms of skin itching.

BACKGROUND

Approximately 8-38% of children with Kawasaki disease (KD) will have persistent or recrudescent fever after initial intravenous immunoglobulin (IVIG) treatment and are at increased risk for development of coronary artery abnormalities. Using genetic markers may be helpful to identify the high-risk group of IVIG-resistant patients for aggressive treatment. The aim of this study was to evaluate the associations between 4 potential polymorphisms in the interleukin (IL)-1 family of genes and initial IVIG treatment failure in KD children.

RESULTS

A total of 156 KD children (136 with and 20 without a response to IVIG treatment) who were treated with high-dose IVIG (2 g/kg) within 10 days of fever onset were recruited. Polymerase chain reaction and Taqman assays were used for genotyping. A significant increase in IVIG resistance risk was observed for IL-1B -511 TT and IL-1B -31 CC genotypes (adjusted odds ratio (AOR) 5.27, 95% confidence interval (CI) 1.69-16.38, P=0.004; AOR 3.95, 95%CI 1.26-12.41, P=0.019, separately). The diplotype TC/TC (at IL-1B -511 and -31) also showed a significantly increased risk of IVIG resistance (AOR 4.32, 95%CI 1.36-13.71, P=0.013).

CONCLUSIONS

The IL-1B -511 TT and IL-1B -31 CC genotypes or the TC/TC diplotype may be associated with initial IVIG treatment failure in Taiwanese children with KD.

The immune response of diabetic patients to influenza vaccination was examined in <em>31</em> patients, 10 with Type 1 (insulin-dependent) diabetes and 21 with Type 2 (non-insulin-dependent diabetes), and in 19 normal subjects. Each received a single intramuscular injection of the 3 virus strains (A/Chile,A/Philippines,B/USSR) anti-influenza vaccine recommended by WHO. The antibody titre and the cell-mediated immune response to the 3 virus strains, as evaluated by the generation of activated lymphocytes and enumeration of B lymphocytes, were studied before and 18 h, 72 h and 1, 2, 3 and 6 weeks after vaccination. Overall, the humoral and cell-mediated immune responses were normal in both groups of patients. However, patients with Type 1 diabetes showed a statistically significant increase (p less than 0.01) of antibody titre of the A/Chile and an increased percentage of B lymphocytes one week after vaccination compared to age-matched control subjects. Four out of 21 patients with Type 2 diabetes had no antibody response to all 3 virus strains. A significant reduction (p less than 0.01) of the percentage of activated cells possessing receptors for <em>interleukin</em>-2 was observed 72 h after vaccination in patients with Type 2 diabetes compared to age-matched control subjects. None of the patients who received the vaccine developed influenza in the course of the following year. These results suggest that valid protection against the influenza virus can be obtained in patients with Type 1 and Type 2 diabetes.

OBJECTIVE

To identify changes in plasma cytokine levels after image-guided thermal ablation of human tumors and to identify the factors that independently predict changes in plasma cytokine levels.

METHODS

Whole-blood samples were collected from 36 patients at three time points: before ablation, after ablation (within 48 hours), and at follow-up (1-5 weeks after ablation). Plasma levels of interleukin (IL)-1α, IL-2, IL-6, IL-10, and tumor necrosis factor (TNF)-α were measured using a multiplex immunoassay. Univariate and multivariate analyses were performed using cytokine level as the dependent variable and sample collection, time, age, sex, primary diagnosis, metastatic status, ablation site, and ablation type as the independent variables.

RESULTS

There was a significant increase in the plasma level of IL-6 after ablation compared with before ablation (9.6-fold ± 31-fold, P<.002). IL-10 also showed a significant increase after ablation (1.9-fold ± 2.8-fold, P<.02). Plasma levels of IL-1α, IL-2, and TNF-α were not significantly changed after ablation. Cryoablation resulted in the largest change in IL-6 level (>54-fold), whereas radiofrequency ablation and microwave ablation showed 3.6-fold and 3.4-fold changes, respectively. Ablation of melanomas showed the largest change in IL-6 48 hours after ablation (92×), followed by ablation of kidney (26×), liver (8×), and lung (6×) cancers. Multivariate analysis revealed that ablation type (P<.0003) and primary diagnosis (P<.03) were independent predictors of changes to IL-6 after ablation. Age was the only independent predictor of IL-10 levels after ablation (P< .019).

CONCLUSIONS

Image-guided thermal ablation of tumors increases plasma levels of IL-6 and IL-10, without increasing plasma levels of IL-1α, IL-2, or TNF-α.

BACKGROUND

Some experimental trials have demonstrated that rapamycin (RAPA) is able to inhibit HIV-1 progression in three different ways: (1) reducing CCR5-gene transcription, (2) blocking interleukin-2 intracellular secondary messenger (mammalian target of rapamycin), and (3) up-regulating the beta-chemokine macrophage inflammatory protein (MIP; MIP-1alpha and MIP-1beta). We present the preliminary results of a prospective nonrandomized trial concerning the first HIV patient series receiving RAPA monotherapy after liver transplantation (LT).

METHODS

Since June 2003, 14 HIV patients have received cadaveric donor LT due to end-stage liver disease (ESLD) associated or not associated with hepatocellular carcinoma, scored by the model for ESLD system. Patients were assessed using the following criteria for HIV characterization: CD4 T-cell count more than 100/mL and HIV-RNA levels less than 50 copies/mL. Primary immunosuppression was based on calcineurin inhibitors (CI), whereas switch to RAPA monotherapy occurred in cases of CI complications or Kaposi's sarcoma.

RESULTS

Mean overall post-LT follow-up was 14.8 months (range: 0.5-52.6). Six of 14 patients were administered RAPA monotherapy. Mean preswitch period from CI to RAPA was 67 days (range: 10-225 days). Mean postswitch follow-up was 11.9 months (range: 2-31 months). All patients were affected by ESLD, which was associated with hepatocellular carcinoma in seven patients. ESLD occurred due to hepatitis C virus (HCV)-related hepatopathy for nine patients, hepatitis B virus-related hepatopathy for one patient, and hepatitis B virus-HCV hepatopathy for four patients. Significantly better control of HIV and HCV replication was found among patients taking RAPA monotherapy (P=0.0001 and 0.03, respectively).

CONCLUSIONS

After in vitro and in vivo experimental evidence of RAPA antiviral proprieties, to our knowledge, this is the first clinical report of several significant benefits in long-term immunosuppression maintenance and HIV-1 control among HIV positive patients who underwent LT.

Background ST-segment-elevation myocardial infarction is associated with an intense acute inflammatory response and risk of heart failure. We tested whether <em>interleukin</em>-1 blockade with anakinra significantly reduced the area under the curve for hsCRP (high sensitivity C-reactive protein) levels during the first 14 days in patients with ST-segment-elevation myocardial infarction (VCUART3 [Virginia Commonwealth University Anakinra Remodeling Trial 3]). Methods and Results We conducted a randomized, placebo-controlled, double-blind, clinical trial in 99 patients with ST-segment-elevation myocardial infarction in which patients were assigned to 2 weeks treatment with anakinra once daily (N=33), anakinra twice daily (N=<em>31</em>), or placebo (N=35). hsCRP area under the curve was significantly lower in patients receiving anakinra versus placebo (median, 67 [interquartile range, 39-120] versus 214 [interquartile range, 1<em>31</em>-394] mg·day/L; <i>P</i><0.001), without significant differences between the anakinra arms. No significant differences were found between anakinra and placebo groups in the interval changes in left ventricular end-systolic volume (median, 1.4 [interquartile range, -9.8 to 9.8] versus -3.9 [interquartile range, -15.4 to 1.4] mL; <i>P</i>=0.21) or left ventricular ejection fraction (median, 3.9% [interquartile range, -1.6% to 10.2%] versus 2.7% [interquartile range, -1.8% to 9.3%]; <i>P</i>=0.61) at 12 months. The incidence of death or new-onset heart failure or of death and hospitalization for heart failure was significantly lower with anakinra versus placebo (9.4% versus 25.7% [<i>P</i>=0.046] and 0% versus 11.4% [<i>P</i>=0.011], respectively), without difference between the anakinra arms. The incidence of serious infection was not different between anakinra and placebo groups (14% versus 14%; <i>P</i>=0.98). Injection site reactions occurred more frequently in patients receiving anakinra (22%) versus placebo (3%; <i>P</i>=0.016). Conclusions In patients presenting with ST-segment-elevation myocardial infarction, <em>interleukin</em>-1 blockade with anakinra significantly reduces the systemic inflammatory response compared with placebo. Clinical Trial Registration URL: https://www.clinicaltrials.gov/. Unique identifier: NCT01950299.

OBJECTIVE

The changes in iron status occurring during the course of heart failure (HF) and the underlying pathomechanisms are largely unknown. Hepcidin, the major regulatory protein for iron metabolism, may play a causative role. We investigated iron status in a broad spectrum of patients with systolic HF in order to determine the changes in iron status in parallel with disease progression, and to associate iron status with long-term prognosis.

RESULTS

Serum concentrations of ferritin, transferrin saturation (Tsat), soluble transferrin receptor (sTfR), and hepcidin were assessed as the biomarkers of iron status in 321 patients with chronic systolic HF [age: 61 ± 11 years, men: 84%, left ventricular ejection fraction: <em>31</em> ± 9%, New York Heart Association (NYHA) class: 72/144/87/18] at a tertiary cardiology centre and 66 age- and gender-matched healthy subjects. Compared with healthy subjects, asymptomatic HF patients had similar haematological status, but increased iron stores (evidenced by higher serum ferritin without distinct inflammation, P < 0.01) with markedly elevated serum hepcidin (P < 0.001). With increasing HF severity, patients in advanced NYHA classes had iron deficiency (ID) (reduced serum ferritin, low Tsat, high sTfR), iron-restricted erythropoiesis (reduced haemoglobin, high red cell distribution width), and inflammation (high serum high-sensitivity-C-reactive protein and <em>interleukin</em> 6), which was accompanied by decreased circulating hepcidin (all P < 0.001). In multivariable Cox models, low hepcidin was independently associated with increased 3-year mortality among HF patients (P < 0.001).

CONCLUSIONS

Increased level of circulating hepcidin characterizes an early stage of HF, and is not accompanied by either anaemia or inflammation. The progression of HF is associated with the decline in circulating hepcidin and the development of ID. Low hepcidin independently relates to unfavourable outcome.

<em>Interleukin</em> 1 beta (IL-1 beta) is produced as a biologically inactive <em>31</em> kD precursor, which is converted to the active 18 kD form by proteolytic processing. Keratinocytes express IL-1 beta but not the active form of the specific IL-1 beta converting enzyme (ICE). We have recently presented evidence that IL-1 beta activation in human epidermis occurs via an alternative mechanism involving hitherto unknown proteases. We asked whether stratum corneum chymotryptic enzyme (SCCE), which is a serine protease specifically expressed in keratinizing squamous epithelia, can act as an IL-1 beta activator in vitro. Recombinant human pro-IL-1 beta was incubated with recombinant SCCE, and the reaction products were characterized as regards molecular size and ability to induce expression of E-Selectin in human umbilical cord endothelial cells. SCCE caused degradation of pro-IL-1 beta and the accumulation of a component with electrophoretic mobility slightly lower than recombination mature IL-1 beta. Whereas incubation mixtures with pro-IL-1 beta which had been incubated in the absence of SCCE, or with SCCE, which had been incubated in the absence of pro-Il-1 beta, did not induce expression above baseline levels of E-Selectin, pro-Il1 beta which had been incubated with SCCE induced a significant increase in E-Selectin expression. This effect could be abolished by neutralizing antibodies to IL-1 beta, but not by antibodies to IL-1 alpha. In addition to IL-1 beta activation, SCCE also prepared to be able to catalyze a further degradation of IL-1 beta, leading to a loss of biological activity. We conclude that SCCE is a potential candidate for being responsible for IL-1 beta activation in human epidermis.

Different activation parameters of peripheral blood mononuclear cells (PBMC) from <em>31</em> patients with oral lichen planus (OLP) were examined and compared with 23 healthy donors. Impaired spontaneous (450 +/- 241 vs 1290 +/- 480 cpm) and mitogen-induced (39580 +/- 14470 vs 67000 +/- 11810 cpm) lymphocyte blastogenesis was observed in OLP patients. Furthermore, reduced cytokine production was found after phytohemagglutinin A (PHA) stimulation for all cytokines studied-tumour necrosis factor alpha (TNF alpha, 432.2 +/- 73.4 vs 979.8 +/- 46.3 units/ml), <em>interleukin</em> 2 (IL-2, 156.2 +/- 14.9 vs 572.6 +/- 12.9 pg/ml), interferon gamma (IFN gamma, 48.5 +/- 11.9 vs 82.6 +/- 12.4 pg/ml) and <em>interleukin</em> 6 (IL-6, 253.6 +/- 57.7 vs 1,419.0 +/- 279.6 units/ml)-except for <em>interleukin</em> 1 beta (IL-1 beta) and lymphotoxin (LT). In contrast, unstimulated culture supernatants showed increased TNF alpha (38.2 +/- 13.1 vs 8.0 +/- 0.2 units/ml), LT (10.2 +/- 2.2 units/ml vs < 0.4) and IL-6 (18.5 +/- 5.6 units/ml vs < 0.5) activity. Similarly, elevated concentrations of TNF alpha (19.6 +/- 6.3 units/ml) and IL-6 (22.9 +/- 4.7 units/ml) were detected in the sera of OLP patients. Combination of PHA and phorbol myristate acetate (PMA) could restore OLP proliferative T cell response and cytokine production to the level of healthy donors, whereas exogenous recombinant human IL-2 (rhuIL-2) plus PMA did not seem to be an effective stimulant for OLP T cells. These results indicate an alteration in the immune condition of OLP patients and an impairment in T lymphocyte function.

Dietary omega-3 fatty acids retard coronary atherosclerosis. Previously, we demonstrated that dietary omega-3 fatty acids reduce platelet-derived growth factor (PDGF)-A and PDGF-B mRNA levels in unstimulated, human mononuclear cells (MNCs). In a randomized, investigator-blinded intervention trial, we have now compared the effect of ingestion of 7 g/d omega-3, omega-6, or omega-9 fatty acids for 4 weeks versus no dietary intervention on PDGF-A, PDGF-B, heparin-bound epidermal growth factor (HB-EGF), monocyte chemoattractant protein-1 (MCP-1), and <em>interleukin</em>-10 gene expression in unstimulated MNCs and in monocytes that were adherence-activated ex vivo in a total of 28 volunteers. In unstimulated MNCs, mRNA steady-state levels of PDGF-A, PDGF-B, and MCP-1 were reduced by 25+/-10%, <em>31</em>+/-13%, and 40+/-14%, respectively, after omega-3 fatty acid ingestion, as assessed by quantitative polymerase chain reaction (all P<0.05). In monocytes that were adherence-activated ex vivo for 4 and 20 hours, mRNA steady-state levels of PDGF-A, PDGF-B, and MCP-1 were reduced by 25+/-13%, 20+/-15%, and 30+/-8%, respectively (all P<0.05). <em>Interleukin</em>-10 and HB-EGF mRNA steady-state levels were not influenced by omega-3 fatty acid ingestion. Expression of all respective mRNAs in control volunteers or in those ingesting omega-6 or omega-9 fatty acids were not altered. We conclude that human gene expression for PDGF-A, PDGF-B, and MCP-1, factors thought relevant to atherosclerosis, is constitutive, is constant, and can be reduced only by dietary omega-3 fatty acids in unstimulated and adherence-activated monocytes.

BACKGROUND

Myocardial dysfunction is a common and important problem in donor hearts. The mechanisms responsible remain unclear. We have studied the cytokines tumor necrosis factor (TNF)-alpha and interleukin-6 (IL-6) in the myocardium and serum from donors with myocardial dysfunction (unused donors) and compared them with donors with good ventricular function (used donors) and patients with advanced heart failure (HF).

RESULTS

Clinical details and ventricular function were assessed in 46 donors (31 used, 15 unused). Real-time reverse transcription-polymerase chain reaction, Western blotting, and immunocytochemistry were performed on myocardium and immunoassays on serum. TNF-alpha mRNA was 1.6-fold higher in unused than in used donors (P:<0.005) and 1.74-fold higher than in 36 patients with HF. IL-6 mRNA was 2.4-fold higher in unused than in used donors (P:<0.0001) and 4.67-fold higher than in HF (P:<0.0001). Western blotting showed higher TNF-alpha in unused (218. 3+/-6.4, n=4 versus 187.3+/-5.4, n=3 OD units) than used donors (P:<0.05). TNF-alpha expression was localized to cardiac myocytes. Serum TNF-alpha was higher in unused (8.72+/-1.3 pg/mL, n=13) than in used (6.12+/-0.8 pg/mL, n=25, P:<0.05) donors and HF (4.0+/-0.4 pg/mL, n=17, P:<0.005). Serum TNF-alpha receptors did not differ between unused (4.3+/-0.8 and 8.6+/-1.6 ng/mL, n=10) and used (3. 5+/-0.4 and 6.5+/-1.1 ng/mL, n=24) donors. There was a trend for higher serum IL-6 in unused (16.5+/-2.9 pg/mL, n=9) compared with used (13.9+/-1.6 pg/mL, n=26, P:=NS) donors.

CONCLUSIONS

This study documented an increase in the expression of TNF-alpha and IL-6 in the myocardium of all donor hearts that was more marked in the dysfunctional (unused) donor hearts. This was accompanied by similar changes in the serum. This might have important therapeutic implications.

OBJECTIVE

Recent studies indicate that brain natriuretic peptide (BNP(1-32)) may be truncated into BNP(3-32) by dipeptidyl peptidase IV (DPP4) and that BNP(3-32) has reduced biological activities compared with BNP(1-32). We investigated if DPP4 contributes to the cardiorenal alterations and to the attenuated response to BNP seen in heart failure.

RESULTS

Haemodynamic and renal assessment was performed in 12 pigs at baseline, 4 weeks after pacing-induced heart failure, and during BNP infusion. They were randomized to either placebo or treatment with a DPP4 inhibitor, sitagliptin. After 4 weeks of pacing, heart rate was reduced compared with baseline in the sitagliptin group (60 ± 2 vs. 95 ± 16 b.p.m., P < 0.01), and an increase in stroke volume was observed in the sitagliptin group compared with placebo (+24 ± 6% vs. -17 ± 7%, P < 0.01). Glomerular filtration rate declined at week 4 compared with baseline in the placebo group (1.3 ± 0.4 vs. 2.3 ± 0.3 mL/kg/min, P < 0.01) but remained preserved in the sitagliptin group [1.8 ± 0.2 vs. 2.0 ± 0.3 mL/kg/min, P = NS (non-significant)]. In the sitagliptin group, BNP infusion improved end-systolic elastance (68 ± 5 vs. <em>31</em> ± 4 mmHg/kg/mL, P < 0.05), ventricular-arterial coupling, and mechanical efficiency. Compared with controls (n = 6), myocardial gene expression of BNP, <em>interleukin</em>-6, Na(+)-Ca(2+) exchanger, and calmodulin was up-regulated in the placebo group, but not in the sitagliptin group.

CONCLUSIONS

In pacing-induced heart failure, DPP4 inhibition preserves the glomerular filtration rate, modulates stroke volume and heart rate, and potentiates the positive inotropic effect of exogenous BNP at no energy expense.

Ceramides (Cer) are implicated in obesity-associated skeletal muscle and perhaps adipocyte insulin resistance. We examined whether the sphingolipid content of human subcutaneous adipose tissue and plasma varies by obesity and sex as well as the relationship between ceramide content and metabolic indices. Abdominal subcutaneous adipose biopsies were performed on 12 lean adults (males = 6), 12 obese adults (males = 6) for measurement of sphingolipid content and activity of the main ceramide metabolism enzymes. Blood was sampled for glucose, insulin (to calculate homeostasis model assessment-estimated insulin resistance (HOMA(IR))) adiponectin, and <em>interleukin</em>-6 (IL-6) concentrations. Compared to lean controls, total ceramide content (pg/adipocyte) was increased by <em>31</em>% (P < 0.05) and 34% (P < 0.05) in obese females and males, respectively. In adipocytes from obese adults sphingosine, sphinganine, sphingosine-1-phosphate, C14-Cer, C16-Cer, and C24-Cer were all increased. C18:1-Cer was increased in obese males and C24:1-Cer in obese females. For women only, there was a negative correlation between C16-Cer ceramide and plasma adiponectin (r = -0.77, P = 0.003) and a positive correlation between total ceramide content and HOMA(IR) (r = 0.74, P = 0.006). For men only there were significant (at least P < 0.05), positive correlations between adipocyte Cer-containing saturated fatty acid and plasma IL-6 concentration. We conclude that the sexual dimorphism in adipose tissue behavior in humans extends to adipose tissue sphingolipid content its association with adiponectin, IL-6 and insulin resistance.

OBJECTIVE

The aim of this study was to investigate the concentrations of T cell derived cytokines in the synovial fluids (SFs) of patients with psoriatic arthritis (PsA) in comparison with rheumatoid arthritis (RA) and osteoarthritis (OA).

METHODS

Th1 type cytokines (interleukin 2 (IL2), tumour necrosis factor beta (TNF beta), and interferon gamma (INF gamma) and Th2 type cytokines (IL4, IL10) were measured by means of enzyme linked immunosorbent assays.

RESULTS

IL2 was usually not detectable in any of the disease groups. TNF beta was found in 3 of 31 PsA SFs (mean (SEM) 11.1 (2.3) pg/ml) and in a significantly lower concentration than in 20 of the 40 RA SFs (42.2 (15.6) pg/ml; p < 0.002). INF gamma was measurable in 2 of 10 PsA and 6 of 16 RA SFs (p>> 0.05). IL4 was present at low concentrations in 4 of 22 PsA SFs (0.41 (0.8) pg/ml), and in 15 of 20 RA SFs (0.63 (0.09) pg/ml; p < 0.01). IL10 was found in 4 of 27 PsA SFs (12.3 (0.9) pg/ml) and in 27 of 32 RA SFs (37.3 (4.9) pg/ml; p < 0.0001). In all OA SFs cytokine concentrations were below the limit of detection.

CONCLUSIONS

The pattern of T cell derived cytokines in PsA SFs was similar to that of RA SFs. However, both the frequency and the concentrations of cytokines were lower in PsA SFs than in RA SFs, while OA SFs generally lacked any detectable T cell cytokines altogether. The presence of Th1 and Th2 cell derived cytokines in PsA SFs suggests the presence of activated T cells in the inflamed joint tissues and their participation in the immunoinflammatory events.

Despite apparent relationships between ischemic stroke and the acute phase response (APR), considerable variation in the APR exists between individuals. We therefore performed post-hoc analysis of individual APR profiles in <em>31</em> patients with ischemic stroke in relation to volume of brain infarction. Patients with ischemic stroke had serial blood samples taken within 12 h, and up to 12 months of symptom onset, for analysis of plasma C-reactive protein (CRP) and <em>interleukin</em>-6 (IL-6). Computed tomography (CT) brain infarct volume was measured at 5 to 7 days (median 23.9 cm(3)). An increase in plasma CRP after the admission sample was evident in 94% of patients by day 5 to 7 (median increase 558% of admission value). CRP response, assessed as area under the curve between admission and day 5 to 7, correlated strongly (r=0.62, p<0.001) with CT infarct volume. Those with greater infarct volumes had more evidence of infection, either prior to or during the first week after stroke. The pattern of response was similar for IL-6, although only 77% showed an increase in plasma IL-6 after the admission sample (median increase 148% of admission value). These data suggest that, although infection and other factors may contribute to systemic inflammation, the extent of acute brain injury after ischemic stroke is a major factor influencing the magnitude and variability of the APR.

Endotoxin stimulates the release of the inflammatory cytokines <em>interleukin</em> (IL)-1, IL-6, and tumor necrosis factor (TNF)-alpha, which are potent activators of the hypothalamic-pituitary-adrenal (HPA) axis. Recent studies in the rodent and in the primate have shown that the HPA responses to endotoxin and IL-1 were enhanced by gonadectomy and attenuated by estradiol (E2) replacement. In addition, there is some evidence, in the rodent, that estrogen modulates inflammatory cytokine responses to endotoxin. To determine whether estrogen has similar effects in humans, we studied the cytokine and HPA responses to a low dose of endotoxin (2--3 ng/kg) in six postmenopausal women with and without transdermal E2 (0.1 mg) replacement. Mean E2 levels were 7.3 +/- 0.8 pg/mL in the unreplaced subjects and increased to 102 +/- 13 pg/mL after estrogen replacement. Blood was sampled every 20 min for 1--2 h before, and for 7 h after, iv endotoxin administration. Endotoxin stimulated ACTH, cortisol, and cytokine release in women with and without E2 replacement. E2 significantly attenuated the release of ACTH (P < 0.0001) and of cortisol (P = 0.02). Mean ACTH levels peaked at 190 +/- 91 pg/mL in the E2-replaced group vs. 411 +/- 144 pg/mL in the unreplaced women, whereas the corresponding mean cortisol levels peaked at 27 +/- 2.9 microg/dL with E2 vs. <em>31</em> +/- 3.2 microg/dL without E2. Estrogen also attenuated the endotoxin-induced release of IL-6 (P = 0.02), IL-1 receptor antagonist (P = 0.003), and TNF-alpha (P = 0.04). Mean cytokine levels with and without E2 replacement peaked at 341 +/- 94 pg/mL vs. 936 +/- 620 pg/mL for IL-6, 82 +/- 14 ng/mL vs. 133 +/- 24 ng/mL for IL-1 receptor antagonist, and 77 +/- 46 pg/mL vs. 214 +/- 87 pg/mL for TNF-alpha, respectively. We conclude that inflammatory cytokine and HPA responses to a low dose of endotoxin are attenuated in postmenopausal women receiving E2 replacement. These data show, for the first time in the human, that a physiological dose of estrogen can restrain cytokine and neuroendocrine responses to an inflammatory challenge.

Tandem repeat number polymorphism of a CCTTT pentanucleotide in the promoter region of the inducible nitric oxide synthase gene (iNOS) and a polymorphism of the <em>interleukin</em>-1beta (IL-1B) promoter at position -<em>31</em> were analyzed in DNA samples from 181 Japanese control subjects and 158 gastric cancer patients, including 96 intestinal type and 62 diffuse type. An association between the intestinal type of gastric adenocarcinoma and higher promoter activity of the iNOS gene was found in women, especially those having higher promoter activity of the IL-1B gene and without a history of smoking. Our results imply that chronic inflammation caused by excess nitric oxide generated by iNOS contributes to Helicobacter pylori-induced gastric cancer.

IL-1beta is a pro-inflammatory cytokine with multiple biological effects and is a potent inhibitor of gastric acid secretion, and IL-1RN has been shown to be associated with enhanced IL-1beta production in vitro. Recently, it was reported that the pro-inflammatory genotypes, IL-1B -<em>31</em> C/+ and IL-1RN *2/*2, were associated with an increased risk of gastric cancer in a Caucasian population. We tested the association between the polymorphisms and 190 gastric cancer, 117 duodenal ulcer, and 172 healthy subjects as controls in the Korean population. The allele frequency of IL-1B -<em>31</em> C was more prevalent in Korean (51%) than in Caucasian (30%), while the frequency of IL-1RN *2 allele was less in Korean (6%) than in Caucasian (27%). Using the IL-1B TT genotype as a reference group, the CC genotype was not associated with an increased risk of gastric cancer or duodenal ulcer in the Korean population (odds ratios (OR)=0.90, 95% confidence interval (CI)=0.50-1.64; OR=0.72, 95% CI=0.36-1.46, respectively). Similarly, IL-1RN*2 was not a risk genotype for either gastric cancer or duodenal ulcer. No association was recognized on the haplotype analysis of the two genes, either. Our results did not support the previous report that IL-1B -<em>31</em> C/IL-1RN*2 polymorphisms were associated with an increased risk of gastric cancer. The lack of association with duodenal ulcer also suggested that the polymorphisms were not directly related to the acid-secreting capability.

Pulmonary infection with Pseudomonas aeruginosa is characterized by massive airway inflammation, which comprises significant cytokine production. Although mast cells are abundant in the lung and are potent sources of various cytokines, a role of mast cells in P. aeruginosa infection remains undefined, and P. aeruginosa-induced signaling mechanisms in mast cells have not been studied previously. Here we demonstrate that human cord blood-derived mast cells, mouse bone marrow-derived mast cells, and the mouse mast cell line MC/9 produce significant amounts of <em>interleukin</em> 6 (IL-6) in response to P. aeruginosa. This response was accompanied by a stimulation of protein kinase Calpha (PKCalpha) phosphorylation and PKC activity and was significantly blocked by the PKC inhibitors Ro <em>31</em>-8220 and PKCalpha pseudosubstrate. Interestingly, mast cells treated with P. aeruginosa had reduced protein levels of phosphatase 2A catalytic unit (PP2Ac), which prompted us to determine whether a direct association between PKCalpha and PP2A occurs in mast cells. In mouse bone marrow-derived mast cells and MC/9 cells, as well as in the human mast cell line HMC-1, PP2A coimmunoprecipitated with PKCalpha either using PKCalpha- or PP2Ac-specific antibodies, suggesting that PKCalpha and PP2Ac are physically associated in mast cells. The PP2A inhibitor okadaic acid induced P. aeruginosa-like responses in mast cells including increased PKCalpha phosphorylation, stimulated PKC activity, and augmented IL-6 production, the last being blocked by the PKC inhibitor Ro <em>31</em>-8220. Finally, okadaic acid potentiated the P. aeruginosa-induced IL-6 production. Collectively, these data provide, to our knowledge, the first evidence of both a direct physical association of PP2A and PKCalpha in mammalian cells and their coinvolvement in regulating mast cell activation in response to P. aeruginosa.

The gp130-like receptor (GPL) is a recently cloned member of the family of type I cytokine receptors. The name reflects its close relationship to gp130, the common receptor subunit of the <em>interleukin</em> (IL)-6-type cytokines. Indeed, the recently proposed ligand for GPL, IL-<em>31</em>, is closely related to the IL-6-type cytokines oncostatin M, leukemia inhibitory factor, and cardiotrophin-1. The second signal transducing receptor for IL-<em>31</em> seems to be the oncostatin M receptor beta (OSMRbeta). The present study characterizes in depth the molecular mechanisms underlying GPL-mediated signal transduction. GPL is a strong activator of STAT3 and STAT5, whereas STAT1 is only marginally tyrosine-phosphorylated. We identify tyrosine residues 652 and 721 in the cytoplasmic region of the longest isoform of GPL (GPL(745)) as the major STAT5- and STAT3-activating sites, respectively. Additionally, we demonstrate Jak1 binding to GPL and its activation in heteromeric complexes with the OSMRbeta but also in a homomeric receptor complex. Most interesting, unlike OSMRbeta and gp130, GPL is insufficient to mediate ERK1/2 phosphorylation. We propose that this is due to a lack of recruitment of the tyrosine phosphatase SHP-2 or the adaptor protein Shc to the cytoplasmic domain of GPL.