Association study of c.910A>G and c.1686C>G polymorphisms in XRCC1 gene with risk of hepatocellular carcinoma in the Chinese population

XRCC1 (human X-ray repair complementing defective repair in Chinese hamster cell 1) gene is considered a potentially important gene influencing the risk of hepatocellular carcinoma (HCC). Our analyses detected two allelic variants of XRCC1, c.910A>G and c.1686C>G. We aimed to investigate whether these polymorphisms influence the risk of HCC. The association between the XRCC1 polymorphisms and the risk of HCC was analyzed in 719 patients and 662 controls by polymerase chain reaction-restriction fragment length polymorphism. Our data suggested that the genotypes and alleles of c.910A>G and c.1686C>G polymorphisms were statistically associated with the risk of HCC. For c.910A>G, the GG genotype was associated with increased risk of developing HCC compared with the AA wild genotype (OR = 1.95, 95%CI = 1.40-2.70, P < 0.0001). For c.1686C>G, the risk of HCC was significantly higher for the GG genotype compared with the CC wild genotype (OR = 1.89, 95%CI = 1.375-2.599, P < 0.0001). Significant differences in the risk of HCC were also found with other genetic models for these two SNPs. The G allele of both c.910A>G and c.1686C>G may contribute to the risk of HCC (G versus A: OR = 1.40, 95%CI = 1.20-1.64, P < 0.0001 and G versus C: OR = 1.38, 95%CI = 1.19-1.61, P < 0.0001, respectively). Our findings suggest that the c.910A>G and c.1686C>G polymorphisms of XRCC1 are associated with the risk of HCC in the Chinese population.

Metformin promotes autophagy and apoptosis in esophageal squamous cell carcinoma by downregulating Stat3 signaling

The antidiabetic drug metformin exerts chemopreventive and antineoplastic effects in many types of malignancies. However, the mechanisms responsible for metformin actions appear diverse and may differ in different types of cancer. Understanding the molecular and cellular mechanisms specific for different cancers is important to optimize strategy for metformin treatment in different cancer types. Here, we investigate the in vitro and in vivo effects of metformin on esophageal squamous cell carcinoma (ESCC) cells. Metformin selectively inhibited cell growth in ESCC tumor cells but not immortalized noncancerous esophageal epithelial cells. In addition to apoptosis, metformin triggered autophagy. Pharmacological or genetic inhibition of autophagy sensitized ESCC cells to metformin-induced apoptotic cell death. Mechanistically, signal transducer and activator of transcription 3 (Stat3) and its downstream target Bcl-2 was inactivated by metformin treatment. Accordingly, small interfering RNA (siRNA)-mediated Stat3 knockdown enhanced metformin-induced autophagy and apoptosis, and concomitantly enhanced the inhibitory effect of metformin on cell viability. Similarly, the Bcl-2 proto-oncogene, an inhibitor of both apoptosis and autophagy, was repressed by metformin. Ectopic expression of Bcl-2 protected cells from metformin-mediated autophagy and apoptosis. In vivo, metformin downregulated Stat3 activity and Bcl-2 expression, induced apoptosis and autophagy, and inhibited tumor growth. Together, inactivation of Stat3-Bcl-2 pathway contributes to metformin-induced growth inhibition of ESCC by facilitating crosstalk between apoptosis and autophagy.

Transcutaneous electric acupoint stimulation reduces intra-operative remifentanil consumption and alleviates postoperative side-effects in patients undergoing sinusotomy: a prospective, randomized, placebo-controlled trial

BACKGROUND

Although opioids are widely used as analgesics in general anaesthesia, they have unpleasant side-effects and can delay postoperative recovery. Acupuncture and related techniques are effective for acute and chronic pain, and reduces some side-effects. We assessed the effect of transcutaneous electric acupoint stimulation (TEAS) on intra-operative remifentanil consumption and the incidences of anaesthesia-related side-effects.

METHODS

Sixty patients undergoing sinusotomy were randomly assigned to TEAS or control group. TEAS consisted of 30 min of stimulation (6-9 mA, 2/10 Hz) on the Hegu (LI4), Neiguan (PC6), and Zusanli (ST36) before anaesthesia. The patients in the control group had the electrodes applied, but received no stimulation. Bispectral index was used to monitor the depth of anaesthesia. Perioperative haemodynamics were recorded, and peripheral blood samples were collected to measure the levels of mediators of surgical stress. The primary end point was intraoperative remifentanil consumption and the secondary endpoints were recovery quality and anaesthesia-related side-effects.

RESULTS

Patients in the TEAS group required 39% less remifentanil during surgery than controls [0.0907 (SD 0.026) μg kg(-1) min(-1) vs 0.051 (0.018) μg kg(-1) min(-1)]. There were no differences in intra-operative haemodynamics or surgical stress between groups. However, the time to extubation and recall in the control group was 16.8 (6.8) min and 23.0 (5.0) min, respectively, significantly longer than that in the TEAS group (P<0.01). TEAS also decreased the incidence of dizziness and pruritus within the first 24 h after surgery (P<0.01).

CONCLUSION

The use of TEAS significantly reduced intra-operative remifentanil consumption and alleviated postoperative side-effects in patients undergoing sinusotomy.

CLINICAL TRIAL REGISTRATION

The trial was registered at clinicaltrials.gov (NCT01700855).

The (1->6)-β-glucan moiety represents a cross-reactive epitope of infection-induced malignancy surveillance

Exposure to pathogen-associated molecular patterns (PAMPs) by vaccination or infection is known to have beneficial effects on neoplastic diseases, although the underlying molecular mechanisms are so far unclear. In this article, we report that Abs against (1→6)-β-d-glucan, a typical microbial PAMP and a major target for high titer circulating natural Abs in healthy human subjects, cross-recognize a novel tumor-associated carbohydrate Ag on cancer cells. The (1→6)-β-glucan cross-reactive moiety is immunologically dominant in tumor cells, as C57BL/6 mice harboring EL-4 solid tumors produced anti-(1→6)-β-glucan Abs and the titer of which significantly correlated with enhanced survival and smaller tumor burden. Moreover, the (1→6)-β-glucan-specific Abs exhibited potent tumoricidal activities in vitro. C57BL/6 mice immunized with Candida albicans produced protective immunity against inoculated EL-4 tumors, which was attributed to the formation of (1→6)-β-glucan-specific Abs. Importantly, (1→6)-β-glucan-specific Abs significantly prolonged the survival and reduced the tumor size in mice inoculated with EL-4 tumors. Our results demonstrate that the (1→6)-β-glucan cross-reactive moiety represents a focal point between infection immunity and cancer surveillance, and natural Abs against this epitope may contribute to the first-line antitumor surveillance in humans. Our data also provide important explanation for the long-observed relationship between feverish infection and concurrent remission from cancer.

The cyclic hexapeptide AcF attenuates sepsis-induced acute lung injury and mortality in rats

OBJECTIVE

The purpose of this study was to elucidate the possible beneficial effects of AcF on acute lung injury (ALI) in a rat model of sepsis.

MATERIALS AND METHODS

Male Sprague-Dawley rats were randomly divided into the following four experimental groups (n = 10 per group): animals undergoing a sham cecal ligature puncture (CLP) (Sham group); animals undergoing CLP (control group); or animals undergoing CLP and treated with saline (Saline group) and animals undergoing CLP and treated with AcF (AcF group). At 24 h after CLP, blood, bronchoalveolar lavage fluid (BALF) and lung tissue were collected. The lung wet/dry weight ratio, Protein concentration and the count of inflammatory cells or neutrophils in the BALF were determined. The pathologic changes in lungs were examined with the optical microscopy. Myeloperoxidase (MPO) activity, the expression of inflammatory cytokines were measured in lung tissue and BALF respectively. Survival rates were recorded at 120h in the four groups in another experiment.

RESULTS

Histology findings revealed acute lung injury in rats in the CLP group, whereas those in the AcF-treated group had mild lung injury. Treatment with AcF significantly attenuated the CLP-induced pulmonary edema and inflammation, as it significantly decreased lung wet/dry ration, protein concentration and the infiltration of inflammatory cells and neutrophils in the lung tissues. In addition, the secretion of inflammatory cytokines, such as TNF-α, IL-6, IL-1b and macrophage inflammatory protein-2 (MIP-2) was decreased in AcF treated group compared with the control saline treated group.

CONCLUSIONS

AcF administration ameliorates acute lung injury in a rat model of sepsis induced by CLP. AcF can be developed as a novel treatment for severe sepsis-induced ALI.

Abstract P4-08-01: Effects of exercise during adjuvant chemotherapy on clinical outcomes in early stage breast cancer

Background: Observational studies suggest that physical activity following a diagnosis of breast cancer may be associated with a lower risk of recurrence and death. Some studies also suggest possible effect modification by disease stage, body mass index, and receptor status. To date, however, there are no randomized trials examining the effects of exercise on disease outcomes in any cancer patient group. Here, we report an exploratory follow-up of disease outcomes from the Supervised Trial of Aerobic versus Resistance Training (START). Patients and Methods: The START Trial was a Canadian multicenter trial that randomized 242 breast cancer patients starting adjuvant chemotherapy to either usual care (n = 82) or supervised aerobic (n = 78) or resistance (n = 82) exercise for the duration of their chemotherapy. The primary efficacy endpoint for this exploratory analysis was disease-free survival (DFS). Secondary endpoints were overall survival (OS), distant disease-free survival (DDFS), and recurrence-free interval (RFI). The two exercise arms were combined for the analysis (n = 160) and selected subgroups were explored. Results: After a median follow-up of 89 months (IQR 81 to 96), there were 25/160 (15.6%) DFS events in the exercise groups and 18/82 (22.0%) in the control group (log-rank p = 0.21). Eight-year DFS was 82.7% for the exercise groups compared with 75.6% for the control group (Hazard ratio [HR] = 0.68, 95% CI = 0.37-1.24). There were 13/160 (8.1%) deaths in the exercise groups and 11/82 (13.4%) in the control group (log-rank p = 0.21). Eight-year OS was 91.2% in the exercise groups compared with 82.7% in the control group (HR = 0.60, 95% CI = 0.27 to 1.33. There were 20/160 (12.5%) DDFS events in the exercise groups and 16/82 (19.5%) in the control group (log-rank p = 0.15). Eight-year DDFS was 86.7% in the exercise groups compared with 78.3% in the control group (HR = 0.62, 95% CI = 0.32 to 1.19). Finally, there were 20/160 (12.5%) RFI events in the exercise groups and 17/82 (20.7%) in the control group (Gray's p = 0.095). Eight-year cumulative incidence of RFI was 12.6% in the exercise groups compared with 21.6% in the control group (HR = 0.58, 95% CI = 0.30 to 1.11). Subgroup analyses for DFS and RFI suggested stronger effects for women who were overweight/obese, had stage II/III cancer, receptor positive tumors, HER2 positive tumors, received taxane-based chemotherapies, and received at least 85% of their intended chemotherapy dose-intensity. The most notable subgroup effect was for patients who received optimal chemotherapy dosing with a borderline significant effect for DFS (HR = 0.50, 95% CI = 0.25 to 1.01) and a significant effect for RFI (HR = 0.38, 95% CI = 0.18 to 0.81). Conclusions: In this exploratory follow-up of the START Trial, there was a suggestion that exercise during adjuvant chemotherapy may improve several efficacy endpoints although none achieved statistical significance. Nevertheless, the magnitude of the effects appear to be meaningful with absolute 8-year survival differences between 7% and 9% and relative rate reductions between 30% and 40%. The START Trial provides the first randomized data to suggest that adding exercise to standard chemotherapy for breast cancer may improve outcomes. A definitive phase III trial is warranted.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P4-08-01.

Influence of acute normovolemic hemodilution on the pharmacokinetics of Cisatracurium Besylate

BACKGROUND

Acute normovolemic hemodilution (ANH) is an efficacious blood conservation strategy for avoiding or reducing allogeneic blood transfusion. In a previous publication, on a different cohort of patients, we demonstrated that cisatracurium's potency and duration of action were not influenced by ANH, but we could not establish which role, if any, pharmacokinetics played.

METHODS

Forty patients were randomly allocated to the ANH or control groups. Patients received cisatracurium single 100 µg kg-1 bolus dose, serial arterial blood samples were collected and assayed for pharmacokinetic analysis.

RESULTS

Central and steady state apparent volumes of distribution (V1, Vdss) and slope factor (γ) were larger, effect-compartment concentration at 50% neuromuscular block was lower in the ANH (90.8±41.6 mL kg-1, 159.1±39.2 mL kg-1, 6.0±0.9 and 136.4±29.1 ng·mL-1) compared with the control group (65.5±26.1 mL kg-1, 134.8±31.8 mL kg-1, 5.5±0.8 and 158.5±26.0 ng·mL-1) respectively. Elimination half-life (t1/2 β) and mean residence time (MRT) were longer in the ANH (37.2±20.9, 23.5±13.2 min) than the control group (26.8±9.8, 16.9±6.2 min), albeit not statistically significant (P=0.051, P=0.051). There were no significant differences in distribution half-life (t1/2 α), effect-compartment equilibration rate-constant (keo), central and total clearances (Clc, Cl) between the ANH (2.4±1.2 min, 0.070±0.013 min-1, 6.1±1.9 mL kg-1 min-1 and 7.7±2.3 mL kg-1 min-1) and control group (1.9±1.2 min, 0.063±0.008 min-1, 7.0±1.8 mL kg-1 min-1 and 8.5±2.1 mL kg-1 min-1) respectively.

CONCLUSION

ANH altered some pharmacokinetic parameters such as significantly larger volumes of distribution. Other parameters such as elimination half-life were considerably longer albeit not statistically significant.

Activation of K(2)P channel-TREK1 mediates the neuroprotection induced by sevoflurane preconditioning

Background

Preconditioning with volatile anaesthetic agents induces tolerance to focal cerebral ischaemia, although the underlying mechanisms have not been clearly defined. The present study analyses whether TREK-1, a two-pore domain K⁺ channel and target for volatile anaesthetics, plays a role in mediating neuroprotection by sevoflurane.

Methods

Differentiated SH-SY5Y cells were preconditioning with sevoflurane and challenged by oxygen–glucose deprivation (OGD). Cell viability and expression of caspase-3 and TREK-1 were evaluated. Rats that were preconditioned with sevoflurane were subjected to middle cerebral artery occlusion (MCAO), and the expression of TREK-1 protein and mRNA was analysed. Neurological scores were evaluated and infarction volume was examined.

Results

Sevoflurane preconditioning reduced cell death in differentiated SH-SY5Y cells challenged by OGD. Sevoflurane preconditioning reduced infarct volume and improved neurological outcome in rats subjected to MCAO. Sevoflurane preconditioning increased levels of TREK-1 mRNA and protein. Knockdown of TREK-1 significantly attenuated sevoflurane preconditioning-induced neuroprotective effects in vitro and in vivo.

Conclusions

Sevoflurane preconditioning-induced neuroprotective effects against transient cerebral ischaemic injuries involve TREK-1 channels. These results suggest a novel mechanism for sevoflurane preconditioning-induced tolerance to focal cerebral ischaemia.

Airborne spread and infection of a novel swine-origin influenza A (H1N1) virus

BACKGROUND

The novel swine-origin influenza A (H1N1) virus (S-O 2009 IV) can cause respiratory infectious diseases in humans and pigs, but there are few studies investigating the airborne spread of the virus. In January 2011, a swine-origin H1N1 epidemic emerged in eastern China that rapidly spread to neighboring farms, likely by aerosols carried by the wind.

METHODS

In this study, quantitative reverse transcription polymerase chain reaction (RT-PCR) was used to detect viruses in air samples from pig farms. Based on two aerosol infection models (Pig and guinea pig), we evaluated aerosol transmission and infection of the novel S-O 2009 IV isolate.

RESULTS

Three novel S-O 2009 IV were isolated from the diseased pig. The positive rate and viral loads of air samples were 26.1% and 3.14-5.72 log₁₀copies/m³ air, respectively. In both pig and guinea pig infection models, the isolate (A/swine/Shandong/07/2011) was capable of forming aerosols and infected experimental animals at a range of 2.0-4.2 m by aerosols, but aerosol route was less efficient than direct contact.

CONCLUSIONS

The results indicated that S-O 2009 IV is able to be aerosolized by infected animals and to be transmitted to susceptible animals by airborne routes.

Globular adiponectin elicits neuroprotection by inhibiting NADPH oxidase-mediated oxidative damage in ischemic stroke

Recent studies indicate that adiponectin can attenuate cerebral ischemic lesions via its functional area located in the C-terminal globular domain, which is called globular adiponectin (gAD). However, the mechanisms underlying this action remain unclear. In this study, we investigated the antioxidant properties of gAD during cerebral ischemia. Adult male C57BL/6 mice received an intracerebral injection of gAD with or without tetrabromocinnamic acid (TBCA, a NADPH oxidase activator). Mice were subjected to middle cerebral artery occlusion (MCAO) after gAD injection. Infarct volume, neurological function, the activity of antioxidant enzymes (superoxide dismutase [SOD], catalase), the content of malondialdehyde (MDA), and the expression of Bax, Bcl-2, cleaved caspase-3 and NADPH oxidase 2 (NOX2) were examined at 24h after MCAO. Infarct volume was attenuated in gAD-transduced mice when compared with mice in the MCAO group, with significant improvement in neurological function. In addition, neuronal apoptosis was attenuated, along with the expression of Bax/Bcl-2 and cleaved caspase 3. Furthermore, the activities of SOD and catalase increased, and the content of MDA reduced. However, TBCA blocked the effect of gAD on cerebral protection and its antioxidant abilities. Taken together, these results demonstrate that the neuroprotective action of gAD may result from the promotion of antioxidant capacity by inhibiting the NOX2 signaling system.

[Effect of autoinducer 2 on Riemerell antatipestifer adherence and invasion to Vero cells]

OBJECTIVE

Autoinducer 2 (AI-2), used to communicate among bacterial species, regulates numerous physiological functions of bacteria. In this study, we studied the effect of AI-2 on adherence and invasion of Riemerella antatipestifer (RA) strain CH3 to Vero cells and transcriptional levels of virulence-related and metabolism-related genes were investigated.

METHODS

To verify whether the adherence and invasion of CH3 was affected by AI-2, we added different concentrations of AI-2 to the cocultures of Vero cells and CH3 and then calculated adherence percentages and invasion percentages of tested groups. We further added AI-2 (184.0 micromol/L) to the tryptone soya broth culture of CH3 and then detected the effect of transcriptional levels of related genes of CH3 using real-time PCR.

RESULTS

The adherence of CH3 to Vero cells was decreased most to 62% with 18.4 micromol/L AI-2 and the invasion of CH3 to Vero cells was increased most to 194% with 184.0 micromol/L AI-2. The result of real-time PCR shows that AI-2 increased transcriptional levels of some virulence-related genes and decreased transcriptional levels of some metabolism-related genes.

CONCLUSION

These results suggest that AI-2 affected adherence and invasion of CH3 to Vero cells. Moreover, AI-2 could regulate some genes of CH3 to modulate particular physiological behaviors.

Establishment of Eimeria tenella (local isolate) in chicken embryos

Development of an in vitro Eimeria (E.) tenella model could be valuable as a tool for vaccine, coccidiostats or molecular biology research. 1.0 × 10,000 sporozoites per 0.1 mL were inoculated into the allantoic cavity of ten-day-old chicken embryos. The complete life-cycle of E. tenella was accomplished in eight-nine days at 37 °C and 70% humidity. The addition of 100 U insulin to the embryos could remarkably improve the output of oocysts. The development of the parasite within the embryos was systematically observed, allowing guidelines to be set regarding the appropriate times at which different developmental stages of the parasite may be sampled.

The Ultrastructural Effects of Sulfachloropyrazine on Toxoplasma gondii Tachyzoites

BACKGROUND

Toxoplasmosis is one of the most common parasitic infections of humans and other mammals. This study was aimed to understand the mechanism of action of veterinary medicine-sulfachloropyrazine (SPZ, 99.97%) against Toxoplasma gondii.

METHODS

T. gondii tachyzoites were soaked in PBS (as a control) or SPZ (250 mg/mL) for 2 h at 37 °C. After being processed, any ultrastructural changes of the tachyzoites that had occurred were observed by Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM).

RESULTS

The tachyzoites from control groups with a uniform size had a smooth surface and intact cell or nuclear membranes. In addition, an oval-shaped nucleus, conoids and micronemes were also observed. By contrast, many parasites from the SPZ-treated groups were detrimentally affected by the treatment. Some appeared to be of the vacuolization in their cytoplasm, with the substantial reduction in the number of dense granules and the blur of some organelles.

CONCLUSION

The morphology and ultrastructure of tachyzoites can be affected significantly by SPZ, which might kill the parasite by inhibiting its energy metabolism, inducing apoptosis and damaging its structure. The study provides an experimental basis for further study on the mechanism of SPZ against T. gondii.

[Mutation of lambdapL/pR-cI857 system for production of bacterial ghost in Escherichia coli]

Bacterial ghost is intact envelope of Gram-negative bacteria, which is produced by the function of the lysis gene E from bacteriophage PhiX174. The expression of the lysis gene E is usually controlled by the thermosensitive lambdapL/pR-cI857 promoter. In this study, we described a mutation (T --> C) at the ninth nucleotide of the OR2 in the lambdapR promoter of the lambdapL/pR-cI857 system by overlap PCR. The bacteriolytic assay showed that the mutation in the lambdapL/pR-cI857 system enhanced the temperature of repressing the expression of gene E up to 37 degrees C. The lysis efficiency of altered lambdapR promoter in Escherichia coli DH5a and avian pathogenic E. coli DE17 was up to 99.9%. The expanded range of temperature will benefit for the production of bacterial ghost.

The luxS gene functions in the pathogenesis of avian pathogenic Escherichia coli

Avian pathogenic Escherichia coli (APEC) causes avian colibacillosis, the most significant infectious bacterial disease of poultry worldwide. LuxS, the product of the luxS gene, mediates the quorum sensing (QS) mechanism. This involves the production of autoinducer-2 (AI-2), which regulates important physiological traits and a variety of adaptive processes in different bacteria. In this study, a luxS gene deleted APEC mutant strain, ΔDE17, was constructed using strain DE17. Analysis of bioluminescence indicated that deletion of the luxS gene abolished the production of the QS signal AI-2 in the bacteria. Further studies showed that deletion of the luxS gene in DE17 reduced the bacterial virulence by 31.5-fold in ducklings, based on the measurement of the 50% lethal dose. The mutant strain reduced significantly the abilities of adherence and invasion, by 50.0% and 40.7% respectively, compared with the wild strain DE17. The mutant strain also showed reduced survival in vivo: the bacterial loads of the mutant strain in infected liver, spleen and blood were 46.4-fold, 5.2-fold, and 3.7-fold reduced, respectively, compared with the wild-type strain DE17. Real-time polymerase chain reaction (PCR) demonstrated further that the mRNA levels of the virulence-related genes iucD, fyuA, vat, ompA, iss, fimC and tsh were significantly decreased in the mutant strain ΔDE17, when compared with DE17 (p < 0.05). In addition, the deletion of the luxS gene reduced the motility of the bacterium. This study suggests that the luxS gene functions in the pathogenesis of diseases caused by avian pathogenic E. coli.

The Effects of Epidural Anaesthesia and Analgesia on Natural Killer Cell Cytotoxicity and Cytokine Response in Patients with Epithelial Ovarian Cancer Undergoing Radical Resection

Objective:

Epidural anaesthesia appears to promote antitumourigenic activity in patients with malignant disease who are undergoing surgery. This study investigated immune function in women with epithelial ovarian cancer undergoing radical resection with either general anaesthesia alone or in combination with epidural anaesthesia.

Methods:

Patients ( n = 61) were randomized to receive either combined general/epidural anaesthesia (study group) or general anaesthesia alone (control group). Natural killer cell cytotoxicity (NKCC) and serum concentrations of four cytokines (interleukin [IL]-1β, -8 and -10 and interferon [IFN]-γ) were measured before anaesthesia ( Tpre) and 4h after skinincision ( T4 h) in both groups.

Results:

In both groups, concentrations of protumourigenic cytokines (IL-1β and IL-8) were significantly higher at T4 h than at Tpre, while concentrations of antitumourigenic cytokines (IL-10 and IFN-γ) and NKCC were significantly lower at T4 h. The study group had significantly higher NKCC, IL-10 and IFN-γ levels and lower IL-1β and IL-8 levels at TT h compared with the control group.

Conclusion:

Combined general/epidural anaesthesia appeared to promote antitumourigenic NKCC and cytokine responses.

Pharmacokinetics and in vivo potency of soluble epoxide hydrolase inhibitors in cynomolgus monkeys

BACKGROUND AND PURPOSE

Soluble epoxide hydrolase inhibitors (sEHIs) possess anti-inflammatory, antiatherosclerotic, antihypertensive and analgesic properties. The pharmacokinetics (PK) and pharmacodynamics in terms of inhibitory potency of sEHIs were assessed in non-human primates (NHPs). Development of a sEHI for use in NHPs will facilitate investigations on the role of sEH in numerous chronic inflammatory conditions.

EXPERIMENTAL APPROACH

PK parameters of 11 sEHIs in cynomolgus monkeys were determined after oral dosing with 0.3 mg·kg(-1). Their physical properties and inhibitory potency in hepatic cytosol of cynomolgus monkeys were examined. Dose-dependent effects of the two inhibitors 1-trifluoromethoxyphenyl-3-(1-propionylpiperidin-4-yl) urea (TPPU) and the related acetyl piperidine derivative, 1-trifluoromethoxyphenyl-3-(1-acetylpiperidin-4-yl) urea (TPAU), on natural blood eicosanoids, were determined.

KEY RESULTS

Among the inhibitors tested, TPPU and two 4-(cyclohexyloxy) benzoic acid urea sEHIs displayed high plasma concentrations (>10 × IC(50)), when dosed orally at 0.3 mg·kg(-1). Although the 4-(cyclohexyloxy) benzoic acid ureas were more potent against monkey sEH than piperidyl ureas (TPAU and TPPU), the latter compounds showed higher plasma concentrations and more drug-like properties. The C(max) increased with dose from 0.3 to 3 mg·kg(-1) for TPPU and from 0.1 to 3 mg·kg(-1) for TPAU, although it was not linear over this range of doses. As an indication of target engagement, ratios of linoleate epoxides to diols increased with TPPU administration.

CONCLUSION AND IMPLICATIONS

Our data indicate that TPPU is suitable for investigating sEH biology and the role of epoxide-containing lipids in modulating inflammatory diseases in NHPs.