Plasma Ammonia Levels Research Articles

Genetic background and clinical characteristics of infantile hyperammonemia.

This study was conducted to analyze the genetic spectrum and clinical characteristics of infantile hyperammonemia. Between January 2016 and June 2020, we retrospectively enrolled infantile hyperammonemia patients with definitive genetic diagnosis at the Children's Hospital of Fudan University. Based on the age of hyperammonemia onset, patients were grouped into neonatal and post-neonatal subgroups to compare their genetic and clinical features. Collectively, 136 pathogenic or likely pathogenic variants of the 33 genes were identified. Fourteen genes were reported with hyperammonemia (42%, 14/33), with SLC25A13 and MUT being the top two detected genes. In contrast, 19 genes, which have not been previously reported with hyperammonemia, were detected (58%, 19/33), in which JAG1 and ABCC8 were the most frequently mutated genes. Compared with post-neonatal hyperammonemia, neonatal patients with hyperammonemia presented with higher rates of organic acidemia (P=0.001) and fatty acid oxidation disorder (P=0.006), but a lower rate of cholestasis (P<0.001). Patients with neonatal hyperammonemia had a higher ratio of peak plasma ammonia level ≥500 µmol/L (P=0.003) and were more likely to receive precision medicine (P=0.027); however, they had a refractory clinical course (P=0.001) and poorer prognosis than the infantile group. There were significant differences in the genetic spectrum, clinical features, clinical course, and outcomes between infants with different hyperammonemia onset ages.

Plasma ammonia levels predict hospitalisation with liver-related complications and mortality in clinically stable outpatients with cirrhosis.

Hyperammonaemia is central in the pathogenesis of hepatic encephalopathy. It also has pleiotropic deleterious effects on several organ systems, such as immune function, sarcopenia, energy metabolism and portal hypertension. This study was performed to test the hypothesis that severity of hyperammonaemia is a risk factor for liver-related complications in clinically stable outpatients with cirrhosis. We studied 754 clinically stable outpatients with cirrhosis from 3 independent liver units. Baseline ammonia levels were corrected to the upper limit of normal (AMM-ULN) for the reference laboratory. The primary endpoint was hospitalisation with liver-related complications (a composite endpoint of bacterial infection, variceal bleeding, overt hepatic encephalopathy, or new onset or worsening of ascites). Multivariable competing risk frailty analyses using fast unified random forests were performed to predict complications and mortality. External validation was carried out using prospective data from 130 patients with cirrhosis in an independent tertiary liver centre. Overall, 260 (35%) patients were hospitalised with liver-related complications. On multivariable analysis, AMM-ULN was an independent predictor of both liver-related complications (hazard ratio 2.13; 95% CI 1.89-2.40; p <0.001) and mortality (hazard ratio 1.45; 95% CI 1.20-1.76; p <0.001). The AUROC of AMM-ULN was 77.9% for 1-year liver-related complications, which is higher than traditional severity scores. Statistical differences in survival were found between high and low levels of AMM-ULN both for complications and mortality (p <0.001) using 1.4 as the optimal cut-off from the training set. AMM-ULN remained a key variable for the prediction of complications within the random forests model in the derivation cohort and upon external validation. Ammonia is an independent predictor of hospitalisation with liver-related complications and mortality in clinically stable outpatients with cirrhosis and performs better than traditional prognostic scores in predicting complications. We conducted a prospective cohort study evaluating the association of blood ammonia levels with the risk of adverse outcomes in 754 patients with stable cirrhosis across 3 independent liver units. We found that ammonia is a key determinant that helps to predict which patients will be hospitalised, develop liver-related complications and die; this was confirmed in an independent cohort of patients.

Altered gut microbiota is associated with sleep disturbances in patients with minimal hepatic encephalopathy caused by hepatitis B-related liver cirrhosis

ABSTRACT Background Sleep disturbances are prevalent in patients with minimal hepatic encephalopathy (MHE). This study aimed to evaluate the association between sleep disturbances and altered gut microbiota in patients with MHE caused by hepatitis B-related liver cirrhosis. Research design and methods Ninety-eight and 45 patients with MHE were included in exploration and validation cohorts, respectively. Sleep disturbances were assessed using the Chinese version of the Pittsburgh Sleep Quality Index (PSQI) questionnaire. Microbiota in fecal samples were analyzed via amplicon sequencing of bacterial 16S ribosomal RNA genes. Results The gut microbiomes of MHE patients with sleep disturbances were characterized by lower bacterial diversity and distinct bacterial composition. Relative abundances of Streptococcus salivarius and Veillonella were independent predictors of sleep disturbances in MHE patients and well-distinguished MHE patients with and without sleep disturbances in both the exploration and validation cohorts. Moreover, the relative abundances of S. salivarius were positively correlated with plasma ammonia levels, and functional modules associated with protein digestion and absorption and lipopolysaccharide biosynthesis were enriched in the microbiomes of MHE patients with sleep disturbances. Conclusions Both S. salivarius and Veillonella were associated with sleep disturbances in patients with MHE caused by hepatitis B-related liver cirrhosis.

Chronic heat stress causes liver damage via endoplasmic reticulum stress-induced apoptosis in broilers

Liver is a central metabolic organ, which is sensitive to heat stress. Liver damage affects animals' health and endangers the livestock and poultry industry. This study aimed to investigate the mechanism of chronic heat stress-induced liver damage in broiler chickens. Broilers were divided into 3 treatments: normal control group (NOR, 22°C), heat stress group (HS, 32°C) and pair-feeding group (PF, 22°C) for a 7-d and 14-d trial. The results showed that 7 d heat exposure caused microvesicular steatosis and reduced glutamine synthetase activity in broiler liver (P < 0.05). After 14 d of heat exposure, heat stress caused vacuolar degeneration and apoptosis in the liver; elevated liver relative weight and liver glutaminase activity as well as plasma ammonia level (P < 0.05). Additionally, heat stress enhanced GRP78 protein expression and the mRNA expressions of endoplasmic reticulum (ER) stress responses genes and apoptosis-related genes in broiler liver after 14 d of heat exposure (P < 0.05). In conclusion, chronic heat stress triggered ER stress-induced apoptosis and caused liver damage, which may compromise ammonia detoxification in broiler liver.

Protective effect of probiotics and ascorbic acid on bile duct ligation-induced chronic hepatic encephalopathy in rats.

Background and purpose:Hepatic encephalopathy (HE) is a brain dysfunction caused by acute and chronic hepatic failure. The pathogenesis of HE is unknown, although small intestinal bacterial overgrowth associated with chronic liver damage, hyperammonemia, and oxidative stress are considered major factors for HE. Effective lowering of circulating ammonia and neuroinflammation is the main strategy for preventing and treating HE in cirrhosis. In the present study, the protective effect of probiotics (Lactobacillus plantarum and Bacillus clausii) and ascorbic acid in combination was assessed in bile duct ligation (BDL)-induced chronic HE in rats.Experimental approach:Sprague Dawley rats were divided into five groups (n = 6). All groups were subjected to double ligation of the bile duct and fed a hyperammonemia diet, except group I (normal control). Groups III and IV were treated with a low and high dose of combination therapy, respectively, while group V was given lactulose. Four weeks post ligation, behavioral, biochemical, and neurochemical parameters were measured. The liver and brain were dissected for histopathology and protein analyses.Findings / Results:Combination therapy reduced plasma AST, ALT, ALP, and ammonia levels and attenuated hepatic inflammation/fibrosis in cirrhotic rats. Furthermore, combination therapy significantly improved behavioral parameters and restored the antioxidant enzyme activity. Histological changes were observed in the brain and liver of BDL animals.Conclusion and implications:The additive impact of probiotics and ascorbic acid on BDL-induced chronic HE in rats was mediated by a reduction in ammonia and oxidative stress, implying the therapeutic potential of combination therapy in HE.

Effects of PCSK-9 Inhibition by Alirocumab Treatments on Biliary Cirrhotic Rats.

Hyperlipidemia and oxidative stress with elevated oxidized low-density lipoprotein (ox-LDL) exacerbate hepatic inflammation and fibrosis. The plasma level of low-density lipoprotein (LDL) is controlled by proprotein convertase subtilisin/kexin 9 (PCSK9). Alirocumab is a monoclonal antibody that decreases LDL via inhibiting PCSK9 function. Apart from lipid-lowering effects, alirocumab exerts anti-inflammation, anti-angiogenesis and anti-oxidant effects. This study aims to investigate the impact of alirocumab treatment on common bile duct ligation (BDL)-induced biliary cirrhotic rats. After a 4-week treatment of alirocumab, the hemodynamic data, blood biochemistry, ox-LDL level, oxidative stress markers, severity of hepatic encephalopathy and abnormal angiogenesis of BDL rats were measured and compared to the control group. BDL rats presented cirrhotic pictures and elevated ammonia, total cholesterol, LDL and ox-LDL levels compared to the control group. Alirocumab decreased plasma levels of total cholesterol, LDL, and oxidative stress markers; however, it did not affect the hemodynamics, liver and renal biochemistry, and the plasma levels of ammonia and ox-LDL. The motor activities, portal-systemic collaterals and mesenteric vascular density were not significantly different between alirocumab-treated and control groups. In addition, it did not affect hepatic inflammation, intrahepatic angiogenesis, liver fibrosis and free cholesterol accumulation in the liver of BDL rats. In conclusion, PCSK9 inhibition by alirocumab treatment ameliorates hyperlipidemia and systemic oxidative stress in biliary cirrhotic rats. However, it does not affect the plasma level of ox-LDL, intrahepatic inflammation and fibrosis. In addition, PCSK9 inhibition has a neutral effect on abnormal angiogenesis and hepatic encephalopathy in biliary cirrhotic rats.

Dining on the dead in the deep: Active NH4 + excretion via Na+ /H+ (NH4 + ) exchange in the highly ammonia tolerant Pacific hagfish, Eptatretus stoutii.

Pacific hagfish are exceptionally tolerant to high environmental ammonia (HEA). Here, we elucidated a cellular mechanism that enables hagfish to actively excrete ammonia against steep ammonia gradients expected to be found inside a decomposing whale carcass. Hagfish were exposed to varying concentrations of HEA in the presence or absence of environmental Na+ , while plasma ammonia levels were tracked. 14 C-methylammonium was used as a proxy for NH4 + to measure efflux in whole animals and in isolated gill pouches; the latter allowed us to assess the effects of amiloride specifically on Na+ /H+ exchangers (NHEs) in gill cells. Western blotting and immunohistochemistry were utilized to evaluate the abundance and sub-cellular localization of Rhesus glycoprotein (Rh) channels in the response to HEA. Hagfish actively excreted NH4 + against steep inwardly directed ENH4 + (ΔENH4 + ~ 35 mV) and pNH3 (ΔpNH3 ~ 2000 μtorr) gradients. Active NH4 + excretion and plasma ammonia hypo-regulation were contingent on the presence of environmental Na+ , indicating a Na+ /NH4 + exchange mechanism. Active NH4 + excretion across isolated gill pouches was amiloride-sensitive. Exposure to HEA resulted in decreased abundance of Rh channels in the apical membrane of gill ionocytes. During HEA exposure, hagfish can actively excrete ammonia against a steep concentration gradient using apical NHEs energized by Na+ -K+ -ATPase in gill ionocytes. Additionally, apical Rh channels are removed from the apical membrane, presumably to reduce ammonia loading from the environment. We suggest that this mechanism allows hagfish to maintain tolerable ammonia levels while feeding inside decomposing carrion, allowing them to exploit nutrient-rich food-falls.

Glutamine synthetase (GS) deficiency can affect ammonia tolerance of yellow catfish Pelteobagrus fulvidraco

Glutamine synthetase (GS) plays a crucial role in the regulation of glutamine synthesis in fish which is a very effective ammonia detoxification strategy. In this study, the full-length GS was cloned from the liver of yellow catfish. The full-length cDNA sequence of GS was 1928 bp in length and encoded 371 amino acids. The amino acid sequence of GS showed high homology (99%) with that of channel catfish. The highest mRNA expression of GS was found in the brain of yellow catfish. Acute ammonia stress (96 h LC50) significantly increased ammonia levels in plasma, liver, and brain, and GS gene expression was significantly up-regulated in the liver and brain. RNA interference inhibited the GS mRNA expression level in primary cultured hepatocytes after acute ammonia stress and reduced hepatocyte survival rate. It is suggested that GS plays a key role in ammonia detoxification in yellow catfish by regulating glutamine synthesis.

Evaluation of silymarin extract from Silybum marianum in mice: anti-fatigue activity

Silymarin has been used for centuries for its hepatoprotective properties. The specific objective of this study was to evaluate the anti-fatigue properties of silymarin. The silymarin was administered orally at doses of 50, 100, and 200mg/kg for 4 weeks; the fatigue level and exercise performance were evaluated using exhaustive swimming time and pole-climbing time, as well as levels of plasma lactate, ammonia, glucose, creatine kinase (CK), serum urea nitrogen (SUN), blood lactic acid (BLA), muscle glycogen (MG), and liver glycogen (LG) contents after an intensive swimming session. The results demonstrated that silymarin treatment decreased the BLA and SUN levels while increased the LG and MG levels. In addition, silymarin decreased plasma lactate and ammonia levels and CK activity after swimming test, this is related to the mechanism that increases energy storage (as glycogen) and release (as blood glucose), and decreases plasma levels of lactate, ammonia, and CK. The observation of the skeletal muscle structures of mice also confirmed that skeletal muscles became more damaged in the control group compared with the silymarin-treated mice after prolonged endurance exercise. Therefore, it is reasonable to infer that silymarin may bear potential pharmacological effects in combating fatigue.

Ammonia Scavenger Restores Liver and Muscle Injury in a Mouse Model of Non-alcoholic Steatohepatitis With Sarcopenic Obesity.

Recent studies have revealed that sarcopenia is closely associated with obesity and non-alcoholic steatohepatitis (NASH). However, few attempted to explore the cause-and-effect relationship between sarcopenic obesity and NASH. In this study, we investigated muscular alterations in a rodent NASH model to elucidate their intrinsic relations and explore the potential therapeutic target. Forty-six 8-week-old and twenty 42-week-old male C57BL/6 mice (defined as young and middle-aged mice, respectively) were fed with a high-fat diet (HFD) for 12 or 20 weeks. A subset of young mice was subjected to ammonia lowering treatment by L-ornithine L-aspartate (LOLA). We examined body composition and muscle strength by nuclear magnetic resonance and grip strength meter, respectively. At the end of the 12th week, all HFD-fed mice developed typical steatohepatitis. Meanwhile, sarcopenia occurred in HFD-fed middle-aged mice, whereas young mice only demonstrated decreased grip strength. Until the end of week 20, young mice in the HFD group exhibited significant sarcopenia and obesity phenotypes, including decreased lean body mass and grip strength, and increased body fat mass and percentage body fat. Additionally, plasma ammonia level was markedly increased in HFD-fed mice of both ages at week 20. Plasma ammonia level was negatively associated with muscle strength and myofiber diameter in young mice. LOLA can significantly reduce plasma levels of ammonia, alanine aminotransaminase, aspartate aminotransaminase, and cholesterol in mice fed an HFD. Hepatic infiltration of inflammatory cells and collagen deposition area were significantly decreased in HFD group by LOLA treatment. Meanwhile, LOLA significantly increased lean body mass, grip strength, and average muscle fiber diameter of HFD-fed mice. These findings suggest that the occurrence of NASH precedes sarcopenia in HFD mice, and the steatohepatitis-related hyperammonemia might contribute to the pathogenesis of sarcopenia. LOLA might be an effective drug for both steatohepatitis and sarcopenic obesity.

Pharmacokinetics/pharmacodynamics of L-ornithine phenylacetate in overt hepatic encephalopathy and the effect of plasma ammonia concentration reduction on clinical outcomes.

Hepatic encephalopathy (HE) is a serious neurocognitive complication of liver dysfunction, often associated with elevated plasma ammonia. Ornithine phenylacetate (OP), a potent ammonia scavenger, is being evaluated for the treatment of acute/overt HE. The pharmacokinetics and pharmacodynamics of OP in patients with HE were characterized in this phase IIb study (NCT01966419). Adult patients hospitalized with an overt HE episode, cirrhosis, and plasma ammonia above the upper limit of normal (ULN) who failed to improve after 48 hours’ standard care were randomly assigned to continuous intravenous OP (10, 15, or 20 g/day, based on Child–Turcotte–Pugh score) or matching placebo for 5 days. Plasma levels of ornithine and phenylacetic acid (PAA) and plasma/urinary levels of phenylacetylglutamine (PAGN) (primary metabolite of PAA) were regularly assessed; plasma ammonia level was the primary pharmacodynamic variable. PAA demonstrated dose‐dependent pharmacokinetics; ornithine and PAGN levels increased with dose. PAGN urinary excretion represented ~50%–60% of administered PAA across all doses. Mean reduction in plasma ammonia with OP at 3 hours postinfusion was significantly greater versus placebo (p = 0.014); and time to achieve plasma ammonia less than or equal to the ULN was significantly reduced (p = 0.028). Achievement of clinical response based on HE stage was associated with a greater reduction in mean plasma ammonia level (p = 0.009). OP effects on plasma ammonia were consistent with its proposed mechanism of action as a primary ammonia scavenger, with a significant association between reduced plasma ammonia and improvement in HE stage. OP should be further evaluated as a promising treatment for hyperammonemia in patients with overt HE.

Air contamination of therapeutic drug monitoring assay reagents results in falsely high plasma ammonia levels.

Accumulating evidence shows that contamination of blood samples by atmospheric ammonia affects blood ammonia test levels; however, reports on the effect of ammonia contamination of assay reagents are limited. Here, we aimed to clarify the effect of ammonia contamination of assay reagents, particularly the therapeutic drug monitoring (TDM) reagents, on the detection levels of blood ammonia using enzymatic assays. Ammonia gas was measured in the refrigerator compartment of the automatic analyser and the reaction tank water, probe wash water and drain outlets connected to the automatic analyser. At different time points following the closure of the cold storage, ammonia levels in quality control plasma samples were measured using three commercial assay reagents to evaluate the effect of air contamination. The distribution of evaporated ammonia in the reagent was measured using the CicaLiquid NH3 assay kit containing the assay reagent most affected by air contamination. It was confirmed that ammonia gas was generated in the cold storage of the automatic analyser. More than half of the reagents detected >0.25 ppm ammonia, and the highest concentration was detected in the TDM reagent. The ammonia levels obtained using all three reagents increased significantly after 3h of air contamination. The effect was resolved by measuring a 'dummy' sample or mixing the reagents by inversion. We demonstrated that air contamination by TDM reagents placed in cold storage could result in significantly falsely high ammonia measurements. Preventing this effect would improve the accuracy of ammonia measurements.

Effects of l-arginine and l-citrulline supplementation in reduced protein diets on cecal fermentation metabolites of broilers under normal, cyclic warm temperature and necrotic enteritis challenge

Feeding reduced protein diets may influence the microbial fermentation in the ceca due to the differences in the diet composition and nutrient digestibility compared to the standard protein diets. Two experiments were conducted to investigate the effects of l-arginine (Arg) and l-citrulline (Cit) supplementations in reduced protein diets on cecal fermentation products including ammonia and fatty acids in broilers raised under standard, cyclic warm temperature (WT), and necrotic enteritis (NE) challenge conditions. Sub-objectives were to examine preserving methods for cecal digesta (snap freezing using liquid nitrogen vs ice) and analytical methods (enzymatic assay vs Berthelot method) to determine cecal ammonia. In experiment 1, Ross 308 cockerels (n = 720) were randomly allocated to four dietary treatments with 12 replicates of 15 birds per pen from d 7 to 21. The treatments were: a standard protein diet (SP), a reduced protein diet with 2.5 percentage points lower crude protein (CP) and deficient in Arg (RP), and RP supplemented with 0.28% Arg (RP-Arg) or 0.28% Cit (RP-Cit). A factorial arrangement of treatments was applied during the finisher phase (21 to 35 d). Factors were: diet (four diets above); and temperature, NT (24 °C) or cyclic WT (33 °C ± 1 °C for 6 h per day) using 6 replicate pens per diet per temperature. In experiment 2, Ross 308 cockerels (n = 720) were randomly assigned to six experimental treatments with eight replicates of 15 birds per pen. The treatments were: a standard protein without NE challenge (SP-); with NE challenge (SP+); reduced protein (1 to 2 percentage points lower CP) without NE challenge (RP-); with NE challenge (RP+);RP+ plus added Arg (103% of Ross 308 requirement, RPA+) and RPC+ where supplemental Arg-in RPA+ was replaced with Cit. The results of experiment 1 showed that birds fed the Arg-deficient RP diet tended to have lower total cecal ammonia levels (P = 0.054) on d 21, and had higher plasma ammonia levels on d 35 (P < 0.05) compared to those fed the SP. Supplementation of Arg-or Cit in the Arg-deficient RP diet reduced plasma ammonia level (P < 0.05) but did not affect total cecal ammonia level compared to the Arg-deficient RP treatment on d 35. Necrotic enteritis challenge decreased total cecal ammonia level (P < 0.01, experiment 1) while cyclic WT did not affect this parameter (experiment 2). Birds exposed to cyclic WT had a lower cecal formic acid level compared to those reared in NT on d 35 (P < 0.05). Preserving samples on ice or by snap freezing with liquid nitrogen during sample collection did not affect recovery of cecal ammonia. Determination of free ammonia level using an enzymatic assay using the Thermo Indiko Plus technique can be used to replace the Berthelot method as a quick assessment tool to evaluate cecal ammonia level in birds.

Dextromethorphan improves locomotor activity and decreases brain oxidative stress and inflammation in an animal model of acute liver failure.

Hepatic encephalopathy (HE) is a serious clinical problem leading to severe neurological disorders and death. No specific treatment is available for the management of HE-associated neurological damage. This study aimed to evaluate the effect of dextromethorphan (DXM) on oxidative stress and disturbed locomotor activity in an animal model of HE. In the current study, BALB/c mice received acetaminophen (APAP; 1000 mg/kg, intraperitoneally [IP]). Dextromethorphan (0.5, 1, 5, 10 mg/kg, subcutaneously [SC]) was injected in three doses (every 6 h), starting two hours after acetaminophen. Animals' locomotor activity, brain and plasma ammonia levels, as well as biomarkers of oxidative stress and inflammatory cytokines in the brain tissue, were assessed 24 hours after acetaminophen injection. It was found that APAP administration was significantly associated with liver damage and increased plasma biomarkers of liver injury. Ammonia levels in plasma and brain tissue of APAP-treated mice also increased significantly. There was also a significant difference in motor activity between the control and APAP-treated animals. The acute liver injury also increased the brain level of pro-inflammatory cytokines (tumor necrosis factor a [TNF-a], interleukin 6 [IL-6], and interleukin 1b [IL-1b]). It was found that DXM could significantly improve the motor activity of animals in all doses and decrease the biomarkers of inflammation and oxidative stress in the brain tissue of animals with hyperammonemia. The effect of dextromethorphan on oxidative stress and inflammation seems to be a major mechanism for its neuroprotective properties in HE. Based on these data DXM could be applied as an effective pharmacological option against HE-associated brain injury.

The role of plasma ammonia level in detecting intra-abdominal hemorrhage following blunt abdominal trauma

Background:Blunt abdominal injury is a major cause of death in trauma cases. It will be very helpful if intra-abdominal bleeding can be predicted by laboratory tests. The aim of our study is to evaluate the accuracy of plasma ammonia in detecting intra-abdominal hemorrhage in patients with blunt abdominal injury.Materials and Methods:In this study, 60 patients admitted to Azadi teaching hospital complaining from blunt abdominal trauma were included. On admission to emergency room, plasma ammonia levels were measured. Demographic data, vital signs, and GCS reports were written down. Findings of abdomino-pelvic computed tomography scan and intraoperative laparotomy were supposed as a gold standard for abdominal injuries. We excluded patients with preexisting liver diseases or impairment.Results:In this study 60 patients were involved. 6 patients had intra-abdominal bleeding and their mean plasma ammonia level was much higher than the rest. (205.33±100.2 vs. 51.29±23.38, P < 0.001). ROC curve analysis revealed Accuracy 96.7% Sensitivity 83.3% Specificity 98.1%.Conclusion:The study results advocate that an increase in plasma ammonia level in patients with blunt abdominal trauma would be a useful predictor for intra-abdominal hemorrhage. This can be a great opportunity for hospitals lacking advanced facilities like contrast enhanced CT scan or diagnostic laparoscopy.

Propionic acidemia in mice: Liver acyl-CoA levels and clinical course

Propionic acidemia (PA) is a severe autosomal recessive metabolic disease caused by deficiency of propionyl-CoA carboxylase (PCC). We studied PA transgenic (Pat) mice that lack endogenous PCC but express a hypoactive human PCCA cDNA, permitting their survival. Pat cohorts followed from 3 to 20 weeks of age showed growth failure and lethal crises of lethargy and hyperammonemia, commoner in males (27/50, 54%) than in females (11/52, 21%) and occurring mainly in Pat mice with the most severe growth deficiency. Groups of Pat mice were studied under basal conditions (P-Ba mice) and during acute crises (P-Ac). Plasma acylcarnitines in P-Ba mice, compared to controls, showed markedly elevated C3- and low C2-carnitine, with a further decrease in C2-carnitine in P-Ac mice. These clinical and biochemical findings resemble those of human PA patients. Liver acyl-CoA measurements showed that propionyl-CoA was a minor species in controls (propionyl-CoA/acetyl-CoA ratio, 0.09). In contrast, in P-Ba liver the ratio was 1.4 and in P-Ac liver, 13, with concurrent reductions of the levels of acetyl-CoA and other acyl-CoAs. Plasma ammonia levels in control, P-Ba and P-Ac mice were 109 ± 10, 311 ± 48 and 551 ± 61 μmol/L respectively. Four-week administration to Pat mice, of carglumate (N-carbamyl-L-glutamic acid), an analogue of N-carbamylglutamate, the product of the only acyl-CoA-requiring reaction directly related to the urea cycle, was associated with increased food consumption, improved growth and absence of fatal crises. Pat mice showed many similarities to human PA patients and provide a useful model for studying tissue pathophysiology and treatment outcomes.

Amino Acid Profile in Malnourished Patients with Liver Cirrhosis and Its Modification with Oral Nutritional Supplements: Implications on Minimal Hepatic Encephalopathy.

Low plasma levels of branched chain amino acids (BCAA) in liver cirrhosis are associated with hepatic encephalopathy (HE). We aimed to identify a metabolic signature of minimal hepatic encephalopathy (MHE) in malnourished cirrhotic patients and evaluate its modification with oral nutritional supplements (ONS) enriched with ß-Hydroxy-ß-methylbutyrate (HMB), a derivative of the BCAA leucine. Post hoc analysis was conducted on a double-blind placebo-controlled trial of 43 individuals with cirrhosis and malnutrition, who were randomized to receive, for 12 weeks, oral supplementation twice a day with either 220 mL of Ensure® Plus Advance (HMB group, n = 22) or with 220 mL of Ensure® Plus High Protein (HP group, n = 21). MHE evaluation was by psychometric hepatic encephalopathy score (PHES). Compared to the HP group, an HMB-specific treatment effect led to a larger increase in Val, Leu, Phe, Trp and BCAA fasting plasma levels. Both treatments increased Fischer’s ratio and urea without an increase in Gln or ammonia fasting plasma levels. MHE was associated with a reduced total plasma amino acid concentration, a reduced BCAA and Fischer´s ratio, and an increased Gln/Glu ratio. HMB-enriched ONS increased Fischer´s ratio without varying Gln or ammonia plasma levels in liver cirrhosis and malnutrition, a protective amino acid profile that can help prevent MHE.

Long-term effectiveness of carglumic acid in patients with propionic acidemia (PA) and methylmalonic acidemia (MMA): a randomized clinical trial

BackgroundPropionic acidemia (PA) and methylmalonic acidemia (MMA) are rare, autosomal recessive inborn errors of metabolism that require life-long medical treatment. The trial aimed to evaluate the effectiveness of the administration of carglumic acid with the standard treatment compared to the standard treatment alone in the management of these organic acidemias.MethodsThe study was a prospective, multicenter, randomized, parallel-group, open-label, controlled clinical trial. Patients aged ≤ 15 years with confirmed PA and MMA were included in the study. Patients were followed up for two years. The primary outcome was the number of emergency room (ER) admissions because of hyperammonemia. Secondary outcomes included plasma ammonia levels over time, time to the first episode of hyperammonemia, biomarkers, and differences in the duration of hospital stay.ResultsThirty-eight patients were included in the study. On the primary efficacy endpoint, a mean of 6.31 ER admissions was observed for the carglumic acid arm, compared with 12.76 for standard treatment, with a significant difference between the groups (p = 0.0095). Of the secondary outcomes, the only significant differences were in glycine and free carnitine levels.ConclusionUsing carglumic acid in addition to standard treatment over the long term significantly reduces the number of ER admissions because of hyperammonemia in patients with PA and MMA.

Efficacy of peritoneal dialysis on encephalopathic patient with Citrullinemia type I

Abstract Citrullinemia type I (CTLN1) clinical spectrum includes an acute neonatal form ("classic" form) and a milder late-onset form (“non-classic" form). Infants with classic form appear normal at birth. Shortly thereafter, they experienced hyperammonemia and develops symptoms. Without prompt intervention, rapid neurological deterioration with seizures, spasticity, loss of consciousness and even death can occur. Continuous venovenous hemofiltration should be started in neonates and children with ammonia levels &amp;gt; 500 µmol/L or even at lower levels if there has been an inadequate response to medical management after 4 hours. Alternatively, but only in centers that lack ability or expertise to perform extracorporeal therapy, peritoneal dialysis can be utilized. The hallmarks of dialysis is rapid lowering of plasma ammonia concentration to avoid neurotoxicity and irreversible brain damage. Objectives To evaluate the effect of peritoneal dialysis on plasma ammonia levels and the clinical outcome in an encephalopathic Egyptian patient with CTLN1. Patient and Methods A 2.5 year old male patient with a classical form of CTLN1was recruited. The first presenting symptom of the patient was poor suckling and disturbed conscious level at the age of 5 day. He was admitted to neonatal intensive-care unit (NICU) with hyperammonemic encephalopathy and abnormal pattern of breathing. He developed apneic attack and underwent mechanical ventilation. The diagnosis of CTLN1 was established with elevated plasma ammonia concentration (350 µmol/L) and plasma citrulline concentration (2570 µmol/L). The patient was managed with peritoneal dialysis for 4 days, together with protein restriction, sodium benzoate, arginine therapy and high caloric intake. Results Plasma ammonia level was decreased with improvement of general condition and conscious level after dialysis. Upon discharge from NICU, the patient was referred to our Genetic clinic and no history of further hospital admission since then. Mild developmental delay mainly cognitive was noted during his regular clinic follow up. Conclusion CTLN1 can present with hyperammonemic encephalopathy which could be lethal if not promptly managed. Peritoneal dialysis proved to be an effective therapy of reducing plasma ammonia rapidly and improving outcome of the patient.

Mitigation of transportation stress in common carp, Cyprinus carpio, by dietary administration of turmeric

Stress is an inevitable and unpredictable process, which can be interceded through various aquaculture practices. Transportation is one of those aqua-husbandry practices that induces stress and immunosuppression in cultured fish. The present study intended to evaluate the ameliorative effects of dietary turmeric on common carp, Cyprinus carpio, based on antioxidant, immunological and tissue health characteristics at pre- and post-transportation. Diets containing four different levels of turmeric [0% (CTL), 0.5% (0.5 T), 1% (1 T), and 2% (2 T)] were fed to common carp (average weight: 45.2 g) for 2 weeks; then, the fish were placed in plastic bags containing 2.5 L water and 5 L pure oxygen and transported for 3 h in a van. Samples of blood and water were collected before and after the transportation. Transportation led to deterioration of the water quality parameters, as evidenced by declines in dissolved oxygen and pH levels, but elevations in alkalinity, total ammonia and unionized ammonia levels. Fish from 1 T treatment exhibited significantly highest water dissolved oxygen post transportation. Significant decrements in plasma total antioxidant capacity (TAC) and total immunoglobulin (Ig) were observed due to transportation-induced stress. Whereas, plasma cortisol, glucose, lactate, alanine aminotransferase (ALT), aspartate aminotransferase (AST), malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), and lysozyme levels enhanced due to transportation-mediated stress in the fish. The transportation stress was mitigated in 0.5 T and 1 T treatments, which were reflected in terms of decrements in plasma cortisol, glucose, ALT, AST, ammonia, SOD (just in 1 T), CAT, and MDA levels, as well as increments in plasma total Ig and TAC levels in the fish. The above findings conclude that turmeric supplementation at 1% could be used as an excellent feed additive in order to ameliorate the adverse effects of transportation in common carp.