Emricasan to prevent new decompensation in patients with NASH-related decompensated cirrhosis.

BACKGROUND & AIMS: Non-alcoholic steatohepatitis is a leading cause of end-stage liver disease. Hepatic steatosis and lipotoxicity cause chronic necroinflammation and direct hepatocellular injury resulting in cirrhosis, end-stage liver disease and hepatocellular carcinoma. Emricasan is a pan-caspase inhibitor that inhibits excessive apoptosis and inflammation; it has also been shown to decrease portal pressure and improve synthetic function in mice with carbon tetrachloride-induced cirrhosis. METHODS: This double-blind, placebo-controlled study randomized 217 individuals with decompensated NASH cirrhosis 1:1:1 to emricasan (5 mg or 25 mg) or placebo. Patients were stratified by decompensation status and baseline model for end-stage liver disease-sodium (MELD-Na) score. The primary endpoint comprised all-cause mortality, a new decompensation event (new or recurrent variceal hemorrhage, new ascites requiring diuretics, new unprecipitated hepatic encephalopathy ≥grade 2, hepatorenal syndrome, spontaneous bacterial peritonitis), or an increase in MELD-Na score ≥4 points. RESULTS: There was no difference in event rates between either of the emricasan treatment groups and placebo, with hazard ratios of 1.02 (95% CI 0.59-1.77; p = 0.94) and 1.28 (95% CI 0.75-2.21; p = 0.37) for 5 mg and 25 mg of emricasan, respectively. MELD-Na score progression was the most common outcome. There was no significant effect of emricasan treatment on MELD-Na score, international normalized ratio, total serum bilirubin, albumin level or Child-Pugh score. Emricasan was generally safe and well-tolerated. CONCLUSIONS: Emricasan was safe but ineffective for the treatment of decompensated NASH cirrhosis. However, this study may guide the design and conduct of future clinical trials in decompensated NASH cirrhosis. LAY SUMMARY: Patients with decompensated cirrhosis related to non-alcoholic steatohepatitis are at high risk of additional decompensation events and death. Post hoc analyses in previous pilot studies suggested that emricasan might improve portal hypertension and liver function. In this larger randomized study, emricasan did not decrease the number of decompensation events or improve liver function in patients with a history of decompensated cirrhosis related to non-alcoholic steatohepatitis. CLINICALTRIALS. GOV IDENTIFIER: NCT03205345.

Gut commensal derived-valeric acid protects against radiation injuries.

BACKGROUND: Hematopoietic and intestinal systems side effects are frequently found in patients who suffered from accidental or medical radiation exposure. In this case, we investigated the effects of gut microbiota produced-valeric acid (VA) on radiation-induced injuries. METHODS: Mice were exposed to total body irradiation (TBI) or total abdominal irradiation (TAI) to mimic accidental or clinical scenarios. High-performance liquid chromatography (HPLC) was performed to assess short-chain fatty acids (SCFAs) in fecal pellets. Oral gavage with VA was used to mitigate radiation-induced toxicity. Gross examination was performed to assess tissue injuries of thymus, spleen and small intestine. High-throughput sequencing was used to characterize the gut microbiota profile. Isobaric tags for relative and absolute quantitation (iTRAQ) were performed to analyze the difference of protein profile. Hydrodynamic-based gene delivery assay was performed to silence KRT1 in vivo. RESULTS: VA exerted the most significant radioprotection among the SCFAs. In detail, VA replenishment elevated the survival rate of irradiated mice, protected hematogenic organs, improved gastrointestinal (GI) tract function and intestinal epithelial integrity in irradiated mice. High-throughput sequencing and iTRAQ showed that oral gavage of VA restored the enteric bacteria taxonomic proportions, reprogrammed the small intestinal protein profile of mice following TAI exposure. Importantly, keratin 1 (KRT1) played a pivotal role in the radioprotection of VA. CONCLUSIONS: Our findings provide new insights into gut microbiota-produced VA and underpin that VA might be employed as a therapeutic option to mitigate radiation injury in pre-clinical settings.

A randomized, placebo-controlled trial of emricasan in patients with NASH and F1-F3 fibrosis.

BACKGROUND & AIMS: Non-alcoholic steatohepatitis (NASH) is characterized by hepatocyte steatosis, ballooning, and lobular inflammation which may lead to fibrosis. Lipotoxicity activates caspases, which cause apoptosis and inflammatory cytokine (IL-1ß and IL-18) production. Emricasan is a pan-caspase inhibitor that decreases serum aminotransferases and caspase activation in patients with NASH. This study postulated that 72 weeks of emricasan treatment would improve liver fibrosis without worsening of NASH. METHODS: In this double-blind, placebo-controlled study 318 patients were randomized 1:1:1 to twice-daily treatment with emricasan (5 mg or 50 mg) or matching placebo for 72 weeks. Patients had definite NASH and NASH CRN fibrosis stage F1-F3, as determined by a central reader, on a liver biopsy obtained within 6 months of randomization. RESULTS: Emricasan treatment did not achieve the primary objective of fibrosis improvement without worsening of NASH (emricasan 5 mg: 11.2%; emricasan 50 mg: 12.3%; placebo: 19.0%; odds ratios vs. placebo 0.530 and 0.588, with p = 0.972 and 0.972, respectively) or the secondary objective of NASH resolution without worsening of fibrosis (emricasan 5 mg: 3.7%; emricasan 50 mg: 6.6%; placebo: 10.5%; odds ratios vs. placebo 0.334 and 0.613, with p = 0.070 and 0.335, respectively). In the small subset of patients with consistent normalization of serum alanine aminotransferase over 72 weeks, emricasan may have improved histologic outcomes. CONCLUSIONS: Emricasan treatment did not improve liver histology in patients with NASH fibrosis despite target engagement and may have worsened fibrosis and ballooning. Caspase inhibition lowered serum alanine aminotransferase in the short-term but may have directed cells to alternative mechanisms of cell death, resulting in more liver fibrosis and hepatocyte ballooning. CLINICAL TRIAL NUMBER: Clinical Trials.gov #NCT02686762. LAY SUMMARY: Non-alcoholic steatohepatitis (NASH) is characterized by fat accumulation in liver cells, which leads to inflammation and fibrosis. Emricasan was previously shown to inhibit some of the liver enzymes which lead to liver inflammation and fibrosis. In this study, emricasan did not improve liver inflammation or fibrosis in patients with NASH and pre-existing liver fibrosis.

Randomized placebo-controlled trial of emricasan for non-alcoholic steatohepatitis-related cirrhosis with severe portal hypertension.

BACKGROUND & AIMS: Emricasan, an oral pan-caspase inhibitor, decreased portal pressure in experimental cirrhosis and in an open-label study in patients with cirrhosis and severe portal hypertension, defined as a hepatic venous pressure gradient (HVPG) ≥12 mmHg. We aimed to confirm these results in a placebo-controlled study in patients with non-alcoholic steatohepatitis (NASH)-related cirrhosis. METHODS: We performed a multicenter double-blinded study, randomizing 263 patients with NASH-related cirrhosis and baseline HVPG ≥12 mmHg to twice daily oral emricasan 5 mg, 25 mg, 50 mg or placebo in a 1:1:1:1 ratio for up to 48 weeks. The primary endpoint was change in HVPG (ΔHVPG) at week 24. Secondary endpoints were changes in biomarkers (aminotransferases, caspases, cytokeratins) and development of liver-related outcomes. RESULTS: There were no significant differences in ΔHVPG for any emricasan dose vs. placebo (-0.21, -0.45, -0.58 mmHg, respectively) adjusted for baseline HVPG, compensation status, and non-selective beta-blocker use. Compensated patients (n = 201 [76%]) tended to have a greater decrease in HVPG (emricasan all vs. placebo, p = 0.06), the decrease being greater in those with higher baseline HVPG (p = 0.018), with a significant interaction between baseline HVPG (continuous, p = 0.024; dichotomous at 16 mmHg [median], p = 0.013) and treatment. Biomarkers decreased significantly with emricasan at week 24 but returned to baseline levels by week 48. New or worsening decompensating events (∼10% over median exposure of 337 days), progression in model for end-stage liver disease and Child-Pugh scores, and treatment-emergent adverse events were similar among treatment groups. CONCLUSIONS: Despite a reduction in biomarkers indicating target engagement, emricasan was not associated with improvement in HVPG or clinical outcomes in patients with NASH-related cirrhosis and severe portal hypertension. Compensated patients with higher baseline HVPG had evidence of a small treatment effect. Emricasan treatment appeared safe and well-tolerated. LAY SUMMARY: Cirrhosis (scarring of the liver) is the main consequence of non-alcoholic steatohepatitis (NASH). Cirrhosis leads to high pressure in the portal vein which accounts for most of the complications of cirrhosis. Reducing portal pressure is beneficial in patients with cirrhosis. We studied the possibility that emricasan, a drug that improves inflammation and scarring in the liver, would reduce portal pressure in patients with NASH-related cirrhosis and severe portal hypertension. Our results in a large, prospective, double-blind study could not demonstrate a beneficial effect of emricasan in these patients. CLINICAL TRIAL NUMBER: Clinical Trials.gov #NCT02960204.

Duration of Pivalate-conjugated Antibiotics and Blood Glucose Levels Among Pediatric Inpatients: Causal Mediation Analyses and Systematic Review.

BACKGROUND: Several cases of hypoglycemia potentially induced by pivalate-conjugated antibiotics have been reported. However, no observational studies have investigated the associations among children. METHOD: A retrospective cohort study was conducted on 814 consecutive inpatients < 15 years of age with lower respiratory infections. We investigated whether the duration of lower respiratory symptoms and antibiotic use on blood glucose levels and their mediating/moderating effects using multivariable linear regression models and causal mediation analyses. Additionally, we performed a systematic review of the literature that reported the potential associations between pivalate-conjugated antibiotics and hypoglycemia. RESULTS: Multivariable linear regression models showed that the duration of respiratory symptoms and fever had independent relationships with the reduction in blood glucose levels, whereas duration of pivalate-conjugated antibiotic use did not. Causal mediation analyses found that the controlled direct effects of respiratory symptom duration contributed to the reduction in blood glucose levels, but the mediating/moderating effects through antibiotic use did not. A systematic review of the literature included 7 reports written in English and 14 reports written in Japanese. No reports were observational studies; therefore, we were unable to conduct a meta-analysis. CONCLUSIONS: Our study failed to demonstrate an association between duration of pivalate-conjugated antibiotic use and blood glucose levels. Further studies are required to illuminate the relationship.

Mesenchymal Stem Cell Capping on ECM-Anchored Caspase Inhibitor-Loaded PLGA Microspheres for Intraperitoneal Injection in DSS-Induced Murine Colitis.

Mesenchymal stem cells (MSCs) are considered as a promising alternative for the treatment of various inflammatory disorders. However, poor viability and engraftment of MSCs after transplantation are major hurdles in mesenchymal stem cell therapy. Extracellular matrix (ECM)-coated scaffolds provide better cell attachment and mechanical support for MSCs after transplantation. A single-step method for ECM functionalization on poly(lactic-co-glycolic acid) (PLGA) microspheres using a novel compound, dopamine-conjugated poly(ethylene-alt-maleic acid), as a stabilizer during the preparation of microspheres is reported. The dopamine molecules on the surface of microspheres provide active sites for the conjugation of ECM in an aqueous solution. The results reveal that the viability of MSCs improves when they are coated over the ECM-functionalized PLGA microspheres (eMs). In addition, the incorporation of a broad-spectrum caspase inhibitor (IDN6556) into the eMs synergistically increases the viability of MSCs under in vitro conditions. Intraperitoneal injection of the MSC-microsphere hybrid alleviates experimental colitis in a murine model via inhibiting Th1 and Th17 differentiation of CD4+ T cells in colon-draining mesenteric lymph nodes. Therefore, drug-loaded ECM-coated surfaces may be considered as attractive tools for improving viability, proliferation, and functionality of MSCs following transplantation.

Isovalerylshikonin, a new resistance-modifying agent from Arnebia euchroma, supresses antimicrobial resistance of drug-resistant Staphylococcus aureus.

Antimicrobial resistance is the greatest threat to the treatment of bacterial infectious diseases. The development of resistance-modifying agents (RMAs) represents a promising strategy to mitigate the spread of bacterial antimicrobial resistance. In this study, a natural product, isovalerylshikonin (IVS), was isolated from Arnebia euchroma, a traditional Chinese medicine herb, that exhibited marginal antibacterial activity against drug-resistant Staphylococcus aureus RN4220, with a minimum inhibitory concentration (MIC) of 16 mg/L. In addition, a synergistic effect between IVS and streptomycin (STM) was detected by the microdilution antimicrobial chequerboard assay, with a reduction in the MIC of STM by up to 16-fold against strain RN4220. A bacterial ethidium bromide efflux assay and reverse transcription PCR were performed to investigate the synergistic mechanism. IVS significantly inhibited bacterial efflux and expression of msrA mRNA in vitro. A murine peritonitis/sepsis model was employed to test the in vivo synergistic activity of IVS and STM. IVS synergistically decreased bacterial counts with STM in peritoneal, spleen and liver tissue and increased mouse survival with STM in 7 days. The acute toxicity of IVS was tested and the 50% lethal dose (LD50) of IVS with a single exposure was 2.584 g/kg in mice. Overall, IVS, a low-toxicity RMA, exhibited synergistic antibacterial activities in vitro and in vivo against drug-resistant S. aureus. The effects were mediated by suppression of msrA mRNA expression and reduced bacterial efflux. In addition, these data support that IVS is a potential RMA against microbial resistance caused by the MsrA efflux pump.

Randomised clinical trial: emricasan versus placebo significantly decreases ALT and caspase 3/7 activation in subjects with non-alcoholic fatty liver disease.

BACKGROUND: Lipotoxicity leading to excessive caspase-mediated apoptosis and inflammation is believed to drive liver damage in NAFLD. Emricasan is a pan-caspase inhibitor that decreased serum ALT and apoptotic and inflammatory markers in subjects with chronic hepatitis. AIMS: To assess whether 28 days of emricasan would reduce elevated levels of serum ALT, AST, cleaved cytokeratin-18, full-length cytokeratin-18, and caspase 3/7 in subjects with NAFLD and raised aminotransferases. METHODS: Double-blind, placebo-controlled, office-practice study assessed the efficacy, safety, and tolerability of emricasan in subjects with NAFLD and ALT levels ≥1.5 x ULN during screening. Subjects were randomised to emricasan 25 mg twice daily or matching placebo. Subjects with cirrhosis and other causes for raised aminotransferases were excluded. The primary endpoint was the change in ALT at day 28 in the emricasan group vs placebo. RESULTS: 38 subjects were randomised, 19 each to emricasan or placebo. Baseline disease factors were well balanced except for lower median ALT values in emricasan subjects. Three subjects randomised to placebo discontinued prior to day 28. ALT values decreased significantly in emricasan-treated subjects vs placebo at days 7 (P < 0.0001) and 28 (P = 0.02). cCK18 (day 7), flCK18 (days 7 and 28), and caspase 3/7 (day 7) were also significantly decreased in emricasan-treated subjects vs placebo. Emricasan treatment was generally safe and well tolerated. CONCLUSIONS: Emricasan decreased ALT and biomarkers in subjects with NAFLD and raised aminotransferases after 28 days. These results support the further development of emricasan in patients with NAFLD. TRIAL REGISTRATION: ClinicalTrials.gov, Identifier: NCT02077374.

Development of a prodrug of hydantoin based TACE inhibitor.

Our research on hydantoin based TNF-α converting enzyme (TACE) inhibitors led to fused bi-heteroaryl hydantoin series that demonstrate sub-nanomolar potency (Ki) as well as excellent activity in human whole blood (hWBA). However, lead compound 2 posed some formulation challenges which prevented it for further development. A prodrug approach was investigated to address this issue. The pivalate prodrug 3 can be formulated as stable neutral form and demonstrated improved DMPK properties when compared with parent compound.

A case of sudden unexpected infant death involving a homozygotic twin with the thermolabile CPT2 variant, accompanied by rotavirus infection and treatment with an antibiotic containing pivalic acid.

We investigated a case of sudden unexpected death involving a 22-month-old male homozygotic twin infant. After both of the twins had suffered from gastroenteritis, one was found dead in his bed, but his brother survived and has since been healthy. Notably, only the deceased had been treated with an antibiotic containing pivalic acid, which may sometimes cause hypocarnitinemia. Postmortem computed tomography and medicolegal autopsy demonstrated severe liver steatosis, and subsequent genetic analysis revealed that the twin had the thermolabile variant of carnitine palmitoyl transferase 2 (CPT2). On the basis of these facts, we concluded that the cause of death had been fatty acid oxidation deficiency accelerated by an antibiotic containing pivalic acid and virus infection in this infant harboring the thermolabile genetic variant of CPT2. Although each factor alone was not fatal, their combination appeared to have resulted in sudden unexpected infant death.

Exploring the roles of UGT1A1 and UGT1A3 in oral clearance of GSK2190915, a 5-lipoxygenase-activating protein inhibitor.

Pharmacokinetic variability in drug exposure is a concern for all compounds in development including those for the treatment of asthma and other respiratory disorders. Substantial variability in the oral clearance of GSK2190915, a 5-lipoxygenase-activating protein inhibitor that attenuates the production of leukotriene B4 and cysteinyl leukotrienes, is largely unaccounted for by clinical variables. A study of 41 patients, 78% (32/41) of whom were non-Hispanic whites, with mild to moderate asthma identified an association of UGT1A1*28 and UGT1A3*2 with the oral clearance of GSK2190915 (P=3.8×10⁻4 and 1.2×10⁻5, respectively). However, in a subsequent replication study of 403 non-Hispanic white patients with asthma, we failed to observe a statistically significant association between oral clearance of GSK2190915 and either UGT1A1*28 or UGT1A3*2 (P>0.05). Therefore, genetic effects that could explain the systemic exposure level variability of GSK2190915 were not identified.

Novel PPAR pan agonist, ZBH ameliorates hyperlipidemia and insulin resistance in high fat diet induced hyperlipidemic hamster.

Effective and safe pharmacological interventions for hyperlipidemia remains badly needed. By incorporating the key pharmacophore of fibrates into the natural scaffold of resveratrol, a novel structural compound ZBH was constructed. In present study, we found ZBH reserved approximately one third of the sirtuin 1 (SIRT1) activation produced by resveratrol at in-vitro enzyme activity assay, directly bound to and activated all three peroxisome proliferator-activated receptor (PPAR) subtypes respectively in PPAR binding and transactivation assays. Moreover, ZBH (EC50, 1.75 µM) activate PPARα 21 fold more efficiently than the well-known PPAR pan agonist bezafibrate (EC50 37.37 µM) in the cellular transactivation assays. In the high fat diet induced hyperlipidemic hamsters, 5-week treatment with ZBH significantly lowered serum triglyceride, total cholesterol, LDL-C, FFA, hyperinsulinemia, and improved insulin sensitivity more potently than bezafibrate. Meanwhile, serum transaminases, creatine phosphokinase and CREA levels were found not altered by ZBH intervention. Mechanism study indicated ZBH promoted the expression of PPARα target genes and SIRT1 mRNA. Hepatic lipogenesis was markedly decreased via down-regulation of lipogenic genes, and fatty acid uptake and oxidation was simultaneously increased in the liver and skeletal muscle via up-regulation of lipolysis genes. Glucose uptake and utilization was also significantly promoted in skeletal muscle. These results suggested that ZBH significantly lowered hyperlipidemia and ameliorated insulin resistance more efficiently than bezafibrate in the hyperlipidemic hamsters primarily by activating of PPARα, and SIRT1 promotion and activation. ZBH thus presents a potential new agent to combat hyperlipidemia.

Surprising causes of C5-carnitine false positive results in newborn screening.

During an 18-month period, we noticed an alarming increase of newborn screening false positivity rate in identifying isovaleric acidemia. In 50 of 50 newborns presenting elevated C5-carnitine, we confirmed the presence of pivaloylcarnitine. Exogenous pivalate administration had been previously identified as the causal agent of this concern. No pivalic-ester prodrug is commercially available in Belgium, but pivalic derivates are also used in the cosmetic industry as emollient under the term "neopentanoate". We have identified neopentanoate-esters in a nipple-fissure unguent that was provided to young mothers. Ceasing distribution of this product hugely reduced the C5-carnitine false positivity rate.

Efficacy, safety and tolerability of GSK2190915, a 5-lipoxygenase activating protein inhibitor, in adults and adolescents with persistent asthma: a randomised dose-ranging study.

BACKGROUND: GSK2190915 is a high affinity 5-lipoxygenase-activating protein inhibitor being developed for the treatment of asthma. The objective of this study was to evaluate GSK2190915 efficacy, dose-response and safety in subjects with persistent asthma treated with short-acting beta2-agonists (SABAs) only. METHODS: Eight-week multicentre, randomised, double-blind, double-dummy, stratified (by age and smoking status), parallel-group, placebo-controlled study in subjects aged ≥12 years with a forced expiratory volume in 1 second (FEV1) of 50-85% predicted. Subjects (n = 700) were randomised to receive once-daily (QD) oral GSK2190915 (10-300 mg), twice-daily inhaled fluticasone propionate 100 µg, oral montelukast 10 mg QD or placebo. The primary endpoint was mean change from baseline (randomisation) in trough (morning pre-dose and pre-rescue bronchodilator) FEV1 at the end of the 8-week treatment period. Secondary endpoints included morning and evening peak expiratory flow, symptom-free days and nights, rescue-free days and nights, day and night-time symptom scores, day and night-time rescue medication use, withdrawals due to lack of efficacy, Asthma Control Questionnaire and Asthma Quality of Life Questionnaire scores. RESULTS: For the primary endpoint, there was no statistically significant difference between any dose of GSK2190915 QD and placebo. However, repeated measures sensitivity analysis demonstrated nominal statistical significance for GSK2190915 30 mg QD compared with placebo (mean difference: 0.115 L [95% confidence interval: 0.00, 0.23], p = 0.044); no nominally statistically significant differences were observed with any of the other doses. For the secondary endpoints, decreases were observed in day-time symptom scores and day-time SABA use for GSK2190915 30 mg QD versus placebo (p ≤ 0.05). No dose-response relationship was observed for the primary and secondary endpoints across the GSK2190915 dose range studied; the 10 mg dose appeared to be sub-optimal. GSK2190915 was associated with a dose-dependent reduction in urinary leukotriene E4. The profile and incidence of adverse events were similar between treatment groups. CONCLUSION: Efficacy was demonstrated for GSK2190915 30 mg compared with placebo in day-time symptom scores and day-time SABA use. No additional improvement on efficacy endpoints was gained by administration of GSK2190915 doses greater than 30 mg. GSK2190915 was well-tolerated. These results may support further studies with GSK2190915 30 mg. TRIAL REGISTRATION: Clinicaltrials.gov: NCT01147744.

The 5-lipoxygenase-activating protein inhibitor, GSK2190915, attenuates the early and late responses to inhaled allergen in mild asthma.

BACKGROUND: GSK2190915, a potent 5-lipoxygenase-activating protein inhibitor, prevents the synthesis of leukotrienes and 5-oxo-6,8,11,14-eicosatetraenoic acid (5-oxo-ETE). OBJECTIVE: To assess the effect of GSK2190915 on the allergen-induced asthmatic responses. METHODS: Nineteen eligible male subjects with mild asthma were enrolled in and completed this four-centre, double-blind, two-way crossover study (ClinicalTrials.gov NCT00748306). Subjects took GSK2190915 100 mg and placebo orally once daily for 5 days in randomized order. On Day 1 and 4 they had a methacholine challenge, on Day 3 they had an inhaled allergen challenge, and on Days 4 and 6 they had sputum induction. RESULTS: GSK2190915 attenuated the early (0-2 h) and late (4-10 h) asthmatic responses to inhaled allergen compared with placebo. There was a statistically significant attenuation of the early asthmatic response (EAR) by GSK2190915; treatment difference of GSK2190915 vs. placebo for the minimum FEV(1) EAR was 0.408 L (0.205, 0.611). There was a statistically significant attenuation of the late asthmatic response (LAR) by GSK2190915; the treatment difference of GSK2190915 vs. placebo for the minimum FEV(1) LAR was 0.229 L (0.041, 0.417). There was a statistically significant attenuation of allergen-induced sputum eosinophil count on Day 4 following GSK2190915: mean treatment difference (95% CI) between GSK2190915 and placebo was -9.95% (-18.15%, -1.77%). Compared with placebo, GSK2190915 100 mg reduced median sputum LTB(4) by > 90% on Days 4 and 6. There was no effect on methacholine PC(20) post allergen. GSK2190915 was generally well tolerated. CONCLUSION AND CLINICAL RELEVANCE: GSK2190915 shows potential as a treatment for patients with asthma.

A short-term high-dose administration of sodium pivalate impairs pyruvate metabolism without affecting cardiac function.

The pivalate moiety of some oral antibiotics enhances their intestinal absorption, but liberated pivalic acid decreases tissue carnitine concentration and could lead to impaired energy metabolism. The present study investigated the effects of short-term sodium pivalate administration on cardiac functionality and mitochondrial energy metabolism. Wistar rats received sodium pivalate (40 mM) in their drinking water for 14 days, and the carnitine content was measured in heart tissues. The activities of carnitine-dependent enzymes, including carnitine acetyltransferase (CrAT) and carnitine palmitoyltransferase I (CPT I), and the mitochondrial respiration rate were also measured. The isolated rat heart ischemia-reperfusion injury assay was performed based on the Langendorff technique through the reversible occlusion of the left anterior descending coronary artery. The administration of sodium pivalate decreased carnitine concentration in the myocardium by 37 %. Sodium pivalate significantly decreased mitochondrial respiration on pyruvate/malate by 28 %. The activities of CrAT and CPT I in sodium pivalate-treated animals were decreased by 34 and 30 %, respectively. No differences were observed in the infarct size or in the heart functional parameters between the groups. Together, these results indicate that the short-term administration of a high dose of sodium pivalate impairs cardiac mitochondrial energy metabolism without depressing cardiac function during ischemia-reperfusion injury.

Physiological functions of iso-type short-chain fatty acid and omega 3 polyunsaturated fatty acids containing oil in obese OLETF rats.

It has been known that tissues of porpoise contain unique structured-lipids as combination of iso-valeric acid (iso-C5:0) and omega 3 polyunsaturated fatty acids (omega3 PUFAs). It is well known that omega3 PUFAs have lipid-lowering effects in animal and human studies. Although branched chain fatty acids have been interested in their unique functions, there is no data concerning the effect of iso-C5:0 on lipid metabolism. In this study we investigated the effect of structured-lipids from porpoise adipose tissue (porpoise oil) on lipid metabolism in Otsuka Long-Evans Tokushima Fatty (OLETF) rats. For 4 weeks, rats were fed semisynthetic diets containing either 10% corn oil or 5% corn oil plus 5% porpoise oil. After feeding period, the porpoise oil diet significantly alleviated hepatic triglyceride accumulation compared with the control diet in OLETF rats. Although serum triglyceride level increased, serum level of adiponectin that can protect liver function and alleviate abnormalities of lipid and glucose metabolism increased in rats fed porpoise oil diet. In conclusion, results from the present study suggest that porpoise oil feeding prevents the development of fatty liver disease through the enhancement of lipoprotein secretion and increase of adiponectin production in obese rats.

Clinical trial: the efficacy and safety of oral PF-03491390, a pancaspase inhibitor - a randomized placebo-controlled study in patients with chronic hepatitis C.

BACKGROUND: Elevated serum levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) reflect hepatocellular injury in patients with chronic hepatitis C virus (HCV). Increased apoptosis and activated caspases are present in these patients. PF-03491390 inhibits multiple caspases and lowers serum AST and ALT levels in patients with chronic liver diseases. AIM: To determine if treatment with an oral pancaspase inhibitor could reduce serum AST and ALT in patients with HCV. METHODS: Double-blind, randomized, placebo-controlled, parallel-dose study in 204 patients treated with placebo or PF-03491390 (5, 25 or 50 mg) orally twice daily (b.d.) for up to 12 weeks. Serum AST and ALT were monitored weekly. RESULTS: Significant reductions in serum AST and ALT were observed within 1 week of initiating PF-03491390 in all treatment groups (P < 0.0001). These reductions in AST and ALT were maintained throughout the 12 week treatment period and returned to baseline levels when PF-03491390 was discontinued. Increasing the dose did not further lower AST or ALT. The most frequently reported adverse events were headache and fatigue. CONCLUSION: PF-03491390 significantly reduced serum AST and ALT levels in patients with chronic HCV, and was well tolerated over 12 weeks.

Odorant concentration dependence in electroolfactograms recorded from the human olfactory epithelium.

Electroolfactograms (EOGs) are the summated generator potentials of olfactory receptor neurons measured directly from the olfactory epithelium. To validate the sensory origin of the human EOG, we set out to ask whether EOGs measured in humans were odorant concentration dependent. Each of 22 subjects (12 women, mean age = 23.3 yr) was tested with two odorants, either valeric acid and linalool (n = 12) or isovaleric acid and l-carvone (n = 10), each delivered at four concentrations diluted with warm (37 degrees C) and humidified (80%) odorless air. In behavior, increased odorant concentration was associated with increased perceived intensity (all F > 5, all P < 0.001). In EOG, increased odorant concentration was associated with increased area under the EOG curve (all F > 8, all P < 0.001). These findings substantiate EOG as a tool for probing olfactory coding directly at the level of olfactory receptor neurons in humans.

Creatine administration prevents Na+,K+-ATPase inhibition induced by intracerebroventricular administration of isovaleric acid in cerebral cortex of young rats.

Isovaleric acidemia (IVAcidemia) is an inborn error of metabolism due to deficiency of isovaleryl-CoA dehydrogenase activity, leading to predominant accumulation of isovaleric acid (IVA). Patients affected by IVAcidemia suffer from acute episodes of encephalopathy, whose underlying mechanisms are poorly known. In the present study we investigated whether an intracerebroventricular injection of IVA could compromise energy metabolism in cerebral cortex of young rats. IVA administration significantly inhibited (14)CO(2) production from acetate (22%) and citrate synthase activity (20%) in cerebral cortex homogenates prepared 24 h after injection. However, no alterations of these parameters were observed 2 h after injection. In contrast, no significant differences were found in the activities of succinate dehydrogenase, isocitrate dehydrogenase, electron transfer chain complexes or creatine kinase in rats sacrificed 2 or 24 h after IVA administration. Moreover, IVA injection significantly inhibited Na(+),K(+)-ATPase activity (25%) in cerebral cortex of rats 2 or 24 h after IVA administration, while pre-treatment of rats with creatine completely prevented the inhibitory effects of IVA on Na(+),K(+)-ATPase. In conclusion, in vivo administration of IVA inhibits the citric acid cycle probably through the enzyme citrate synthase, as well as Na(+),K(+)-ATPase, a crucial enzyme responsible for maintaining the basal potential membrane necessary for a normal neurotransmission. It is presumed that inhibition of these activities may be involved in the pathophysiology of the neurological dysfunction of isovaleric academic patients. The present findings are of particular interest because treatment with creatine supplementation may represent a potential novel adjuvant therapeutic strategy in IVAcidemia.