Increased Brain Serotonin Rather Than Increased Blood Acetaldehyde as a Common Denominator Behind Alleged Disulfiram-Like Reactions.

Several pharmaceutical agents are known to produce ethanol intolerance, which is often depicted as disulfiram-like reaction. As in the case with disulfiram, the underlying mechanism is believed to be the accumulation of acetaldehyde in the blood, due to inhibition of the hepatic aldehyde dehydrogenases, albeit this has not been confirmed in all cases by blood acetaldehyde measurements. Herein, cefamandole, cotrimoxazole, griseofulvin, procarbazine, and propranolol, which are reported to produce a disulfiram-like reaction, as well as disulfiram, were administered to Wistar rats and the hepatic activities of ethanol metabolizing enzymes along with the levels of brain monoamines were determined. Blood acetaldehyde was also evaluated after ethanol administration in rats pretreated with the abovementioned pharmaceutical products. Disulfiram, cefamandole, and procarbazine significantly increased blood acetaldehyde levels after ethanol administration, while on the contrary, cotrimoxazole, griseofulvin, and propranolol had no effect on blood acetaldehyde. Interestingly, all substances used, except disulfiram, increased the levels of brain serotonin. According to our findings, cotrimoxazole, griseofulvin, and propranolol do not produce a typical disulfiram-like reaction, because they do not increase blood acetaldehyde when given together with ethanol. On the other hand, all tested agents share the common property to enhance brain serotonin, whereas a respective effect of ethanol is well established. Hence, the ethanol intolerance produced by these agents, whether blood acetaldehyde concentration is elevated or not, could be the result of a "toxic serotonin syndrome," as in the case of the concomitant use of serotonin-active medications that provoke clinical manifestations similar to those of a disulfiram reaction.

Evidence for the efficacy of disulfiram and copper combination in glioblastoma multiforme - A propos of a case.

Glioblastoma multiforme (GBM) is the most common and aggressive malignancy of the central nervous system. Treatment usually involves a combination of surgical resection, chemotherapy, and radiotherapy, but ultimately this condition is incurable. Besides the dismal prognosis of GBM, financial factors have also presented challenges for advancing treatments. Taking into consideration the high cost of developing new anticancer drugs as well as the fact that GBM is a rare disease, thus further limiting financial incentive for drug development, it becomes obvious that there has been growing interest for repurposing candidates. One of the most promising drugs to repurpose for treating GBM is disulfiram (DSF). DSF is a relatively nontoxic drug used for more than sixty years in the treatment of chronic alcoholism with the ability to readily cross the blood-brain barrier. Repurposing DSF for use as an anticancer drug in general has recently become of interest because of its preclinically described anticancer effects against various human cancers. Interestingly, a number of these effects were shown to be copper (Cu)-dependent. The purpose of this paper was to review the existing literature surrounding preclinical and clinical data on the effects of DSF -alone or in combination with Cu- in GBM. In addition, we present the first case of a GBM patient safely treated with DSF/Cu combination along with standard therapy exhibiting remarkably increased progression-free (PFS) and overall survival (OS).

The Alcohol Intolerance Produced by Isoniazid Is Not Due to a Disulfiram-Like Reaction Despite Aldehyde Dehydrogenase Inhibition.

BACKGROUND/AIMS: Isoniazid (ISO) has been reported to inhibit the hepatic aldehyde dehydrogenase (ALDH) and to cause a disulfiram (DIS)-like reaction, albeit there are no reports demonstrating increased blood acetaldehyde levels after co-administration of ISO with alcohol. The aim of our study was to clarify whether the alcohol intolerance produced by ISO is indeed due to a typical DIS-like reaction. METHODS: DIS and ISO were administered to Wistar rats and the hepatic ethanol (ETH) metabolizing enzyme activities along with the levels of brain monoamines were determined. Blood acetaldehyde levels were also evaluated after co-administration of ETH with DIS or ISO. RESULTS: Despite inhibition of the hepatic ALDH, ISO did not result in elevated blood acetaldehyde levels after ETH administration, probably due to the induction of cytochrome P450 2E1 which theoretically leads to an increased elimination rate of acetaldehyde preventing its accumulation. Moreover, ISO produced some minor, but statistically significant, alterations in central monoaminergic neurotransmission. CONCLUSION: Our results demonstrate for the first time that despite ALDH inhibition ISO does not provoke a typical DIS-like reaction since it does not increase blood acetaldehyde levels after co-administration with ETH. The possibility that the ETH intolerance observed in ISO treatment is a central synergistic effect cannot be excluded.

Involvement of the brain serotonergic system in the locomotor stimulant effects of chlorpheniramine in Wistar rats: implication of postsynaptic 5-HT1A receptors.

Antihistamines, such as chlorpheniramine (CPA), are lipophilic agents which readily cross the blood-brain barrier, producing sedation in 10-25% of users. However, with excessive doses instead of sedation a stimulating action has been reported. The aim of the present study was to investigate the influence of CPA on the locomotor activity of the rat in relation to its effects on brain biogenic monoamines. Wistar rats were given CPA (40 mg/kg, i.p.) and locomotor activity was measured in a photocell cage. Body temperature was also monitored. In addition, in three brain subregions (striatum, hypothalamus, and midbrain), the levels of 5-HT, NA, DA, as well as their metabolites, were determined by HPLC. Soon after injection, CPA produced a significant increase in locomotor activity, while a hypothermic response was also induced. In striatum and hypothalamus, which are known to be rich in postsynaptic 5-HT1A receptors, we found a significant time-dependent increase of 5-HT, correlated with the clearly enhanced locomotor activity of the animals. On the contrary, in midbrain, where presynaptic 5-HT1A receptors are dominating, no changes could be detected in 5-HT. In all three brain regions measured, 5-HIAA levels were decreased. The levels of the other brain monoamines were only marginally affected. In support of a role in receptor specificity, pretreatment with the 5-HT1A receptor agonist 8-OH-DPAT (1.25 mg/kg, i.p., two times) or with the 5-HT(1A/B) receptor antagonist pindolol (30 mg/kg, i.p., two times), enhanced or blocked, respectively, the hyperlocomotion induced by CPA. These findings suggest that the central serotonergic system may play a key role in the locomotor stimulant effects of CPA in the rat. Moreover, this behavioral component of CPA seems to be primarily mediated via the postsynaptic 5-HT1A receptors.

Risk factors for three phases of 12-month mortality in 1657 patients from a defined population after acute aneurysmal subarachnoid hemorrhage.

OBJECTIVE: To analyze the impact of factors known after admission on mortality attributable to aneurysmal subarachnoid hemorrhage (SAH) resulting from saccular intracranial aneurysm (IA). METHODS: Data of 1657 consecutive patients admitted alive within 24 hours after aneurysmal SAH to Kuopio Neurosurgery during the years 1980-2007 from a defined population were analyzed. RESULTS: Aneurysmal SAH caused excess mortality for 12 months, after which other causes of death became dominant. The 12-month mortality curve on a logarithmic time scale indicated acute (first 3 days), subacute (4-30 days), and delayed (1-12 months) mortality, with cumulative rates of 11% at 3 days, 22% at 30 days, and 27% at 12 months. The acute mortality was predicted by Hunt & Hess (H&H) grades IV-V, ruptured aneurysm ≥ 15 mm, and acute subdural hematoma. Age, gender, intracerebral hemorrhage (ICH), and time period of admission were not independent risk factors. Advanced age, H&H grades IV-V, intraventricular hemorrhage (IVH), giant ruptured saccular IA, ruptured saccular IA on the internal carotid artery or the basilar artery bifurcation, and severe hydrocephalus in different combinations predicted subacute and delayed mortality. Patients in good condition on admission had a mortality rate of only 3.5% at 12 months, regardless of age. CONCLUSIONS: Sequelae of aneurysmal SAH were the leading cause of death for 12 months. Mortality analysis of this period displayed three phases with distinct independent risk factors. These data support the creation of prognosticators for prediction on admission of the everyday individual risk of death until 12 months after aneurysmal SAH.

CYP2E1 and risk of chemically mediated cancers.

IMPORTANCE OF THE FIELD: Among various human CYPs, CYP2E1 is of particular interest because of its involvement in the metabolic activation of many low molecular mass procarcinogens. CYP2E1 induction, which may be a consequence of genetic polymorphism or/and gene induction by xenobiotics, is the first step leading to the development of certain chemically-mediated cancers. The aim of this review is to outline the current knowledge on chemically-induced cancers through activation by CYP2E1, with emphasis on the association between polymorphisms of the CYP2E1 gene and incidence of different neoplasias. AREAS COVERED IN THIS REVIEW: Literature searches of MEDLINE (1966 to July 2009) for English articles in CYP2E1-induced carcinogenesis were conducted. WHAT THE READER WILL GAIN: CYP2E1 genetic polymorphisms leading to enhanced CYP2E1 gene transcription have been associated with increased risk of development of malignant tumours, through increased biotransformation of procarcinogens. Likewise, long-term intake of CYP2E1 inducers, such as ethanol, isoniazid, various solvents and chemicals, also increase the probability of developing malignancy, especially for carriers of certain CYP2E1 alleles. TAKE HOME MESSAGE: Genetic screening for CYP2E1 'carcinogenic' polymorphisms and CYP2E1 phenotype determination of susceptible subjects, as well as the development of effective CYP2E1 inhibitors, could be a future perspective towards prevention of CYP2E1-mediated cancers.

Malignant giant cell tumor in the posterior fossa of a neonate.

Giant cell tumors (GCTs) of the bone are rare, usually benign but locally aggressive neoplasms that primarily occur in the epiphyses of long bones. They seldom develop in the cranium; when they do, they involve principally the sphenoid and temporal bones. These tumors usually affect young adults, and few reports in children have been published. Primary malignant GCTs of the skull are even more uncommon. The 3 published cases all involved adults over 40 years of age. Herein, the authors present a case of a highly aggressive primary malignant GCT of the posterior fossa in a 5-week old preterm infant. One month after the gross-total resection of the tumor found in the bone, the infant's condition rapidly deteriorated and she died. Magnetic resonance imaging and postmortem examination revealed a tumor larger than it had been before the operation, with expansion toward the brain. To the best of the authors' knowledge, this is the youngest patient reported with a primary malignant GCT of the skull, and actually the first case in a pediatric patient. In addition, the extremely high growth rate of the tumor in the postoperative period renders this case the most aggressive primary malignant GCT of the cranium described so far.

Pharmaceutical agents known to produce disulfiram-like reaction: effects on hepatic ethanol metabolism and brain monoamines.

Several pharmaceutical agents produce ethanol intolerance, which is often depicted as disulfiram-like reaction. As in the case with disulfiram, the underlying mechanism is believed to be the accumulation of acetaldehyde in the blood, due to inhibition of the hepatic aldehyde dehydrogenases. In the present study, chloramphenicol, furazolidone, metronidazole, and quinacrine, which are reported to produce a disulfiram-like reaction, as well as disulfiram, were administered to Wistar rats and the hepatic activities of alcohol and aldehyde dehydrogenases (1A1 and 2) were determined. The expression of aldehyde dehydrogenase 2 was further assessed by Western blot analysis, while the levels of brain monoamines were also analyzed. Finally, blood acetaldehyde was evaluated after ethanol administration in rats pretreated with disulfiram, chloramphenicol, or quinacrine. The activity of aldehyde dehydrogenase 2 was inhibited by disulfiram, chloramphenicol, and furazolidone, but not by metronidazole or quinacrine. In addition, although well known for metronidazole, quinacrine also did not increase blood acetaldehyde after ethanol administration. The protein expression of aldehyde dehydrogenase 2 was not affected at all. Interestingly, all substances used, except disulfiram, increased the levels of brain serotonin. According to our findings, metronidazole and quinacrine do not produce a typical disulfiram-like reaction, because they do not inhibit hepatic aldehyde dehydrogenase nor increase blood acetaldehyde. Moreover, all tested agents share the common property to enhance brain serotonin, whereas a respective effect of ethanol is well established. Therefore, the ethanol intolerance produced by these agents, either aldehyde dehydrogenase is inhibited or not, could be the result of a "toxic serotonin syndrome," as in the case of the concomitant use of serotonin-active medications.