[ACTION OF L-CARNITINE, CORVITIN AND THEIR COMBINATION ON FUNCTIONAL STATE OF LIVER IN EXPERIMENTAL MODEL OF REYE SYNDROME IN RATS].

Administration of Aacetylsalicylic acid in children with viral infections (influence B, chickenpox) can be related with development of Reye syndrome - severe encephalopathy and liver insufficiency with mortality in 50% of cases. During Reye syndrome most important is deficiency of carnitine and hepatocyte damage. Decreased amount of carnitine impairs the energy function of mitochondria and gluconeogenesis as well as production of urea. As a result develops toxic encephalopathy and liver insufficiency. The goal of the research was assessment of efficacy of L-Carnitine, Corvitin and their combination on functional state of liver in experimental model of Reye Syndrome in rats. The study was performed on mature white male Wistar rates with body mass 150-180g. 50 rats were randomly divided into 5 groups (10 rats in each group). The model of Reye syndrome was induced in accordance with A.Vengersky's method. Intraperitoneal administration of 4-pentenoic acid was performed once daily during seven days, the used dosage was 20mg/kg. The treatment of toxic hepatitis was carried with intraperitoneal administration of L-Carnitine 300mg/kg, Corvitine 100mg/kg and concurrent administration of these drugs. Monotherapy with Corvitin and L-Carnitin successfully improved liver function and equally decreased indicators of hepatocyte's cytolyses and increased levels of glucose and urea. The markers of cholestasis was slightly more improved during use of L-Carnitine. Simultaneous use of both drugs was effective in rats with Reye syndrome, indicators of liver damage normalized and herewith, no mortality outcome was observed. The most pronounced hepatoprotective effect of concurrent administration of L-Carnitine and Corvitin may be due to synergic action of these drugs and such regime can be recommended for correction of liver function during Reye syndrome.

Mean platelet volume in children with Reye-like syndrome.

Reye-like syndrome (RLS) is considered to be a systemic disorder in which the cytokine storm plays a major role. Mean platelet volume (MPV), which is commonly used as a measure of platelet size, indicates the rate of platelet production and platelet activation. We aimed to study MPV in children with RLS. The study population consisted of 30 children with RLS and 30 healthy control subjects. White blood cell (WBC) count, aspartate transaminase (AST) and alanine transaminase (ALT) values were significantly higher and MPV values were significantly lower in patients with RLS at an early stage of illness when compared to controls. Erythrocyte sedimentation rate (ESR), C-reactive protein, AST and ALT values were significantly decreased in patients with RLS after the treatment when compared to baseline whereas MPV values were increased. MPV values were negatively correlated with ESR and WBC. In conclusion, at an early stage of RLS MPV values were lower when compared to controls.

Resveratrol protects against experimental induced Reye's syndrome by prohibition of oxidative stress and restoration of complex I activity.

This study was designed to investigate whether resveratrol could provide protection against Reye's syndrome induced by 4-pentenoic acid in Wistar albino rats. Compared with rats with untreated Reye's syndrome, 1 h pretreatment by low dose resveratrol (10 mg/kg by oral gavage) resulted in marked amelioration in liver functions in the form of significant decrease in serum transaminases (AST, ALT) and plasma ammonia levels, shortening of prothrombin time, and increase in serum albumin levels. In addition, resveratrol prohibited oxidative stress markers, as indicated by a significant increase in GSH and decrease in MDA, with restoration of complex I activity in liver tissues. The classical histopathological presentation in Reye's syndrome of microvesicular steatosis by light microscope and mitochondria distortion by electron microscope has been improved by resveratrol pretreatment. The efficient protection by resveratrol was determined by normalization in serum levels of AST and albumin, as well as complex I activity, GSH, and MDA. In conclusion, pretreatment by resveratrol in low doses could protect against Reye's syndrome partially via prohibition of oxidative stress and restoration of complex I activity. This may provide the opportunity to reconsider aspirin therapy for infants and young children. However, the verification of such results in clinical practice remains a challenge.

[The Reye syndrome]. / Syndrome de Reye.

The Reye syndrome is a complex disease that remains little-known despite its severity. It can occur in children of all ages, and is often fatal, while surviving children often display neurological damage. The therapy is symptomatic and supportive. The diagnosis of Reye's syndrome is not straightforward, as the symptoms are very diverse. The causes of the disease are moreover still unclear, and, after many years of discussion and research, it can still not be proved irrefutably whether administration of acetylsalicylic acid to children suffering from viral infections is a factor in the development of Reye's syndrome.

The potential of trace amines and their receptors for treating neurological and psychiatric diseases.

Mining of the human genome has revealed approximately 7000 novel proteins, which could serve as potential targets for the development of novel therapeutics. Of these, approximately 2000 are predicted to be G-protein coupled receptors. Within this group of proteins, a family of 18 mammalian receptors has recently been identified that appear to exhibit selectivity toward the so-called trace amines. The trace amines are a family of endogenous compounds with strong structural similarity to classical monoamine neurotransmitters, consisting primarily of 2-phenylethylamine, m- and p-tyramine, tryptamine, m- and p-octopamine and the synephrines. The endogenous levels of these compounds are at least two orders of magnitude below those of neurotransmitters such as dopamine, noradrenaline and 5-HT. The effects of these low physiological concentrations have been difficult to demonstrate but it has been suggested that they may serve to maintain the neuronal activity of monoamine neurotransmitters within defined physiological limits. Such an effect of trace amines would make them ideal candidates for the development of novel therapeutics for a wide range of human disorders. Although the demonstration of a trace amine family of receptors has seen a resurgence of interest in these endogenous compounds, with recent articles reviewing trace amine pharmacological and physiological responses, the potential clinical utility of the trace amine receptors has not been specifically addressed. Historically, trace amines have been implicated in a diverse array of human pathologies ranging from schizophrenia to affective disorders to migraine. Recent studies have strengthened some of this historical data by linking trace amine receptor polymorphisms and mutations to distinct clinical conditions. The aim of the current article is to review the previous studies linking trace amines to human pathology in the context of the recently discovered trace amine receptors and evidence of the existence of trace amine receptor polymorphisms and mutations associated with such disorders. In addition, recent evidence linking trace amines to the development of drug dependence will be discussed.

[Analgesic/Antipyretic treatment: ibuprofen or acetaminophen? An update]. / Traitement analgésique/antipyretique: ibuprofène ou paracétamol? Mise au point.

Because of the adverse effects associated with aspirin, especially Reye's syndrome in children, practitioners currently use as first line therapy drugs such as ibuprofen or acetaminophen. Their pharmacokinetic characteristics are not quite identical: both are absorbed rapidly and have high bioavailability, however, unlike acetaminophen, ibuprofen is characterized by high plasma protein binding and a limited distribution volume. Both drugs are metabolized essentially in the liver into inactive hydroxylated or glucoronidated metabolites by conjugation but acetaminophen is also transformed into an oxidation compound--normally reduced by glutathione--which, in the case of acute overdosing with depletion of endogenous glutathione stores, may lead to severe hepatotoxicity. Old age and light to moderate renal or hepatic failure do not significantly modify their pharmacokinetic parameters, and thus do not call for dose adjustment. Clinical trials have shown both drugs to have comparable efficacy on pain and fever, with perhaps a slight advantage for ibuprofen. In practice, the choice will depend on the prescription habits of the practitioner, patient's (or parents') preferences and, above all, the pathological context and possible contra-indications.

[Therapeutic effect of hepatoprotectors in experimental Reye syndrome]. / [Gepatoprotektory okazyvaiut lechebnoe deistvie pri éksperimental'nom sindrome Reie]

Maxar and legalon--hepatoprotectors containing polyphenols--exhibit a therapeutic effect with respect to the experimental Reye's syndrome induced in rats by intraperitoneal injections of 4-pentenoic acid. Maxar restores the activity of enzymes of the hepatic origin, normalizes the content of bilirubin, glucose, phenols, and malonic aldehyde in the blood serum, stimulates the production of ketone bodies and ammonia detoxication, and improves the histologic structures of liver and cortex. Legalon also decreases the structural-metabolic disorders accompanying the Reye's syndrome, but to as lower ewxtent.

Case summary: Kevin.

Kevin suffered a severe Reye's encephalopathy at the age of 11 weeks which left him severely brain damaged. Simple partial seizures started in the recovery phase and were controlled by carbamazepine. He went on to develop symptomatic infantile spasms that were controlled by the addition of clonazepam. He became progressively microcephalic and investigations confirmed cortical blindness and left hemiparesis. Subsequent seizure types included absences and troublesome generalized myoclonic seizures. Now almost six, he attends a special school and is well controlled on a regimen of sodium valproate, clonazepam and lamotrigine.

Síndrome de Reye : Informe de un caso en adultos

Se describe el caso de una mujer joven atendida en el hospital San Ignacio (Santa Fe de Bogotá), con diagnostico post mortem de síndrome de Reye. Seguidamente, se revisan y discuten los aspectos fisiopatológicos y los concernientes al diagnóstico y la terapéutica.

Evaluation of the possible role of glucose, carnitine, coenzyme Q10 and steroids in the treatment of Reye's syndrome using the margosa oil animal model.

Glucose and steroids have been used in the treatment of children with Reye's syndrome, while carnitine and coenzyme Q10 have been the subject of some recent studies which suggest that these agents may have a role in the treatment of Reye's syndrome and Reye-like syndrome due to margosa oil poisoning. Because of the paucity of causes of Reye's syndrome seen at any one centre, the clinical variability of the disease, and limited knowledge of definite aetiologic factors, controlled clinical trials are not easy to carry out or to interpret in human cases. These caveats were overcome by evaluation of these four treatment modalities in an established margosa-oil-induced animal model of Reye's syndrome. Effectiveness of the treatment modalities was determined from clinical response and histopathologic parameters (grading of light microscopic fatty changes and ultrastructural changes in the hepatocytes). Results show that carnitine per se produces a small improvement in survival, but statistically, more significant benefit is seen with glucose administration. Carnitine plus 10% dextrose appears to produce better results. Evaluation of coenzyme Q10 and carnitine on histopathologic parameters in the liver after a sublethal dose of margosa oil showed no obvious ameliorating effect on liver pathology. Steroids (dexamethasone/methylprednisolone) had no beneficial effects in reducing mortality, affecting glycogen storage or lipid accumulation. Changes in the mitochondria, ribosomes and endoplasmic reticulum were unaltered from the groups treated with margosa oil alone. While glucose and carnitine supplements appear to be beneficial, the other modes of therapy do not seem to hold much promise in the treatment of Reye-like syndrome in the margosa-oil-induced animal model.

Mass spectrometric identification of 2-hydroxydodecanedioic acid and its homologues in urine from patients with hopantenate therapy during clinical episode.

Urine from patients with calcium-4-(2,4-dihydroxy-3,3-dimethylbutyramido) butyrate hemihydrate (hopantenate) therapy during episodes of Reye's-like syndrome was found to contain a number of unusual dicarboxylic acids in high concentrations; odd- and even-numbered medium-chain dicarboxylic acids, alpha-hydroxydicarboxylic acids and beta-hydroxydicarboxylic acids. The abnormal excretion of dicarboxylic acids, alpha- and beta-hydroxydicarboxylic acids disappeared after discontinuance of hopantenate therapy. Besides the excretion of 2-hydroxydecandedioic acid, which has been previously described in Zellweger syndrome or neonatal adrenoleukodystrophy, a series of alpha-hydroxydicarboxylic acids was detected and identified. In this paper, we have characterized some new compounds by gas chromatography/mass spectrometry: 2-hydroxydodecanedioic acid, 2-hydroxydodecenedioic acid, 2-hydroxytetradecanedioic acid, 2-hydroxytetradecenedioic acid and 2-hydroxyoctanedioic acid.

The effect of L-carnitine supplementation in 4 pentenoic acid treated rats.

The effects of prolonged administration (7 days) of 4 pentenoic acid (4PA, 20 mg/kg/day) or 4PA (20 mg/kg/day) with L-carnitine (200 mg/kg/day) on carnitine metabolism and morphological changes of liver mitochondria were assessed in rats. 4PA-treated rats showed hyperammonemia, decreased levels of blood glucose, free fatty acids and beta-OH-butyrate, and of free carnitine in serum, muscle and liver, increased excretion of acylcarnitine in urine, and enlarged mitochondria with microvesicular steatosis, when compared to saline-injected control rats, respectively. 4PA plus L-carnitine rats showed decreased levels of blood ammonia and increased levels of beta-OH-butyrate, compared to the 4PA group. On the other hand, the levels of free carnitine in serum and liver in rats treated with both 4PA and L-carnitine were increased, when compared to controls. The ratio of acylcarnitine to free carnitine excreted in urine in 4PA-treated rats was higher than that in either the control or 4PA plus L-carnitine group. The liver mitochondria in the 4PA plus L-carnitine group were the same as in the controls. The results suggested that the abnormal biochemical and morphological findings due to only 4PA may be relieved with L-carnitine supplementation.

Reye's syndrome in Haemophilus influenzae B septicaemia: case report.

A case of culture-proven Haemophilus influenzae type B septicaemia in association with probably Reye's syndrome is presented. This is the second reported case of Reye's syndrome with this organism and the first in a tropical climate. The features of this child's presentation are described and implications for doctors in areas where Haemophilus influenzae infection is common are discussed.

Inhibition of mitochondrial functions by margosa oil: possible implications in the pathogenesis of Reye's syndrome.

Margosa oil (MO), a fatty acid-rich extract of the seeds of the neem tree and a reported cause of Reye's syndrome, has been used in the induction of an experimental model of Reye's syndrome in rats. It has been reported that MO causes a decrease in in vivo mitochondrial enzyme activity similar to that seen in Reye's syndrome. We have attempted to uncover some of the biochemical mechanisms of MO's toxicity by examining its effect in vitro on isolated rat liver mitochondria. Male rat liver mitochondria were isolated by centrifugation; oxygen uptake, reduced forms of cytochrome b, c + c1, a + a3, and flavoprotein, intramitochondrial concentrations of acetyl coA, acid-soluble coA, acid-insoluble coA, and ATP content were measured after incubation with and without MO. Our results reveal that MO is a mitochondrial uncoupler. State 4 respiration was increased while the respiratory control ratio was decreased. The intramitochondrial content of ATP was also decreased. There were substantial changes in the reduction of the respiratory chain components after incubation of mitochondria with MO. This decelerative effect on mitochondrial electron transport was alleviated by the addition of coenzyme Q and/or carnitine. These effects of MO on mitochondrial respiration may be due to changes in fatty acid metabolism caused by MO as MO caused a shift in the proportion of acid-soluble or acid-insoluble coA esters. Supplementary therapy with L-carnitine and coenzyme Q may be useful in the management of MO-induced Reye's syndrome.

Pharmacology of Reye syndrome.

Reye syndrome, a reversible metabolic encephalopathy and hepatopathy, offers a unique opportunity to investigate the pharmacologic mechanisms by which a toxic-metabolic insult to mitochondria is translated into neurochemical and neurologic dysfunction. Similarity of some clinical and metabolic abnormalities between certain inborn errors of organic acid, ammonia, and carbohydrate metabolism and Reye syndrome suggests a common pathophysiologic mechanism at some level. The primary metabolic aberration in Reye syndrome is unknown. Viral, drug, and toxic precipitants in a conductive host alter glial and neuronal function, possibly by direct toxic effects or by altered transmitter metabolism and signal transduction. These events translate into a rather stereotyped progression of the clinical syndrome. Increased ICP, which is a life-threatening epiphenomenon, is the focus of conventional therapy. Investigational treatments, still in preliminary stages, are aimed at early correction of instigating metabolic abnormalities or correction of their consequences on central neurotransmission. Our fragmentary knowledge of neurotransmitter abnormalities in this disorder, which have suggested disparate interpretations, does not allow a cohesive pharmacologic theory of Reye syndrome. The greatest difficulties in interpretation of possible central mechanisms from existing data, which derive largely from peripheral tissues, is in the differentiation of primary from compensatory changes. The unitarian notion that a single pharmacologic disturbance is the source of the encephalopathy is perhaps too simplistic. It is hoped that future studies of disorders such as Reye syndrome will elucidate the intricate relationships between biochemical pathways and neurotransmitter metabolism.