Kaciński M

Prenatal stress decreases glycogen synthase kinase-3 phosphorylation in the rat frontal cortex

It has been postulated that hyperactive glycogen synthase kinase-3 (GSK-3) is an important factor in the pathogenesis of depression, and that this enzyme also contributes to the mechanism of antidepressant drug action. In the present study, we investigated the effect of prenatal stress (an animal model of depression) and long-term treatment with antidepressant drugs on the concentration of GSK-3beta and its main regulating protein kinase B (PKB, Akt). The concentration of GSK-3beta, its inactive form (phospho-Ser9-GSK-3beta), and the amounts of active (phospho-Akt) and total Akt were determined in the hippocampus and frontal cortex in rats. In order to verify our animal model of depression, immobility time in the forced swim test (Porsolt test) was also determined.We found that prenatally stressed rats display a high level of immobility in the Porsolt test and chronic treatment with imipramine, fluoxetine, mirtazapine and tianeptine normalize this change. Western blot analysis demonstrated that GSK-3beta levels were significantly elevated in the frontal cortex, but not in the hippocampus, of prenatally stressed rats. The concentration of its non-active form (phospho-Ser9-GSK-3beta) was decreased only in the former brain structure. No changes were found in the amounts of active (phospho-Akt) and total Akt in both studied brain structures. Chronic treatment with antidepressant drugs diminished stress-induced alterations in GSK-3beta and phospho-GSK-3beta the frontal cortex, but had no effect on the concentration of these enzymes in the hippocampus. Moreover, levels of Akt and phospho-Akt in all experimental groups remained unchanged. Since our animal model of depression is connected with hyperactivity of the HPA axis, our results suggest that GSK-3beta is an important intracellular target for maladaptive glucocorticoid action on frontal cortex neurons and in antidepressant drug effects. Furthermore, the influence of stress and antidepressant drugs on GSK-3beta does not appear to impact the kinase activity of Akt.

Pharmacodynamic interactions between antiepileptic drugs: preclinical data based on isobolography

Background: At least 20 – 30% of epileptic patients do not sufficiently respond to monotherapy. Some of them can benefit from drug combinations; hence, animal data may provide some useful novel clues for rational polytherapy. Objective: To review combinations of antiepileptic drugs, evaluated with the help of isobolographic analysis, in terms of their efficacy and adverse effects. Methods: A literature search, on the basis of experimental studies, with no time limit was carried out. Results/conclusion: Preclinical data indicate that a synergy occurred for the combinations of valproate + phenytoin, valproate + ethosuximide, lamotrigine + valproate, gabapentin + valproate, gabapentin + carbamazepine, topiramate + carbamazepine, topiramate + valproate, topiramate + oxcarbazepine, levetiracetam + topiramate, levetiracetam + oxcarbazepine, oxcarbazepine + gabapentin, tiagabine + gabapentin and lamotrigine + topiramate. On the other hand, lamotrigine combined with carbamazepine or oxcarbazepine resulted in a clear-cut antagonism. Interestingly, a combination of oxcarbazepine + clonazepam produced variable responses, including synergy, additivity or antagonism, depending on the dose ratio of these drugs. In no case did pharmacokinetic factors contribute to the final analysis of the effects of drug combinations. Pharmacokinetic factors can contribute to the final effect of drug combinations, such as when stiripentol is added to valproate, or clobazam is added to valproate. It may be concluded that the rational treatment of drug-resistant epilepsy needs to consider the results of preclinical studies.

Level of S100B protein, neuron specific enolase, orexin A, adiponectin and insulin-like growth factor in serum of pediatric patients suffering from sleep disorders with or without epilepsy.

BACKGROUND Paroxysmal sleep disorders in children are important from both pathophysiological and clinical point of view. Correct diagnosis is crucial for further management. The aim of the present study was to identify peripheral markers of paroxysmal sleep disorders in children, which could improve diagnostics of these disorders. We compared serum levels of several putative biomarkers of neurological disorders, such as S100B protein, neuron specific enolase (NSE), orexin A, adiponectin, and insulin-like growth factor 1 (IGF-1) in pediatric patients suffering from sleep disturbances with those who additionally to parasomnia revealed also epilepsy. METHODS Fifty six children from 1 month to 18 years of age hospitalized in the Pediatric Neurology Clinic, Chair of Children and Adolescent Neurology, participated in this study. Polysomnographic diagnostics was indicated due to sleep disturbances. Examination was performed with the use of polysomnography and videoelectroencephalography Grass device. Blood samples were taken before registration of sleep, after 2.5 h of sleep or 0.5 h after occurrence of clinical seizures. Concentrations of S100B protein, NSE, orexin A, adiponectin, and IGF-1 were measured by specific ELISA methods. RESULTS The obtained data showed that serum S100B level was significantly increased in children with epilepsy and clinical seizure attacks as compared to patients with parasomnia only. Atendency to enhanced serum S100B level was also seen in epileptic children without clinical seizures during polysomnographic recording. The level of orexin A was significantly decreased in epileptic children without seizures as compared to the hormone level in parasomnic patients, but was elevated in patients who experienced seizures during polysomnographic examination. As S100B is regarded to be a marker of blood brain barrier leakage and astrocyte damage, the data suggest an increase in BBB permeability in epileptic children, especially during seizure fits. Furthermore, the enhanced S100B serum level without changes in NSE activity may be interpreted rather as an evidence of the elevated secretion of this protein during seizures than of the damage of brain tissue. In contrast to S100B and orexin A level, serum concentration of adiponectin and IGF-1 as well as NSE activity did not significantly differ between the studied groups. CONCLUSION Out of the five putative biomarkers measured, blood concentration of S100B and orexin A may be helpful in differentiating parasomnic pediatric patients with and without epilepsy.

Effects of neurosteroids on the human corticotropin-releasing hormone gene

Increased activity of hypothalamic-pituitary-adrenal (HPA) axis and hypersecretion of corticotropin-releasing hormone (CRH) are known to be important factors in pathogenesis of some stress-related diseases. Some neurosteroids exert anxiolytic and antidepressant effects probably by inhibition of HPA axis activity. The aim of our study was to find out if neurosteroids can directly affect human CRH gene transcription. The effect of allopregnanolone (ALLO), allotetrahydrodeoxycorticosterone (THDOC), pregnenolone (PGL), PGL sulfate (PGL-S), dehydroepiandrosterone (DHEA) and DHEA sulfate (DHEA-S) on CRH expression was determined in differentiated Neuro-2A cells stably transfected with plasmid containing a fragment of human CRH promoter (-663 to + 124 bp) linked to the chloramphenicol acetyltransferase (CAT) reporter gene. It was found that PGL (0.3-30 μM), ALLO (1-30 μM) and THDOC (1-30 μM) present in the culture medium for 5 days in the concentration-dependent manner inhibited CRH-CAT activity. These neurosteroids also inhibited forskolin-stimulated CRH gene transcription with similar potency. In contrast, PGL-S, DHEA and DHEA-S in a concentration from 0.01 to 10 μM had no effect on basal and forskolin-stimulated CRH activity. Further experiments revealed that wortmannin (an inhibitor of phosphatidylinositol 3-kinase; PI3-K) at concentrations of 0.01 and 0.02 μM did not change the inhibitory effect of ALLO (3 μM) and PGL (1 μM) on CRH gene transcription. Moreover, ALLO (3 μM) and PGL (1 μM) present in the culture medium for 5 days did not change the amount of active, phosphorylated form of protein kinase B (PKB, Akt) and extracellular signal-regulated kinase (ERK). The obtained results indicate that PGL, ALLO and THDOC inhibited basal and forskolin-induced CRH gene promoter activity in the differentiated Neuro-2A cells and that these effects did not depend on the activation of PI3-K/Akt and ERK-MAPK pathways.

Caudal regression syndrome associated with the white matter lesions and chromosome 18p11.2 deletion

Caudal regression syndrome (CRS) is a rare combination of congenital abnormalities characterized by caudal vertebral agenesis/dysgenesis that is usually associated with congenital anomalies of spinal cord, gastrointestinal and genitourinary organs. Although the exact teratogenic mechanism is not known, same environmental, e.g., hyperglycemia and genetic factors appears to play a crucial role in this fetopathy. Herein, we report an unusual case of CRS associated with unspecific white matter lesions and 18p-syndrome manifested by congenital ptosis, hypothyroidism, facial dysmorphy and chromosome 18p11.2 deletion.

Cluster headache in 2-year-old Polish girl

Cluster headache (CH) is one of the most severe types of primary headache. Intense, unilateral pain in orbital, supraorbital and/or temporal location accompanied by autonomic symptoms is the most characteristic feature. Diagnostic criteria for CH described in the International Classification of Headache Disorders (ICHD), 2nd edition are very helpful in clinical practice and prevent misdiagnosis of this rare type of headache (1). However, diagnosis of CH in the youngest patients is very troublesome due to the lack of patient cooperation. Thorough case history taking and careful parental observation of the child’s behaviour during attacks are crucial in the diagnosis of this type of headache. The patient reported in this paper is one of the youngest with well-documented early childhoodonset CH.

The C242T polymorphism of the gene encoding cytochrome b-245 alpha is not associated with paediatric ischaemic stroke: family-based and case-control study.

BACKGROUND AND PURPOSE Reactive oxygen species play an important role in the physiology and pathology of cerebral arteries, including ischaemic stroke. The cytochrome b-245 alpha gene (CYBA) encodes cytochrome b-245 alpha light chain (p22phox peptide), a critical element of NAD(P)H oxidases, the most important source of superoxide anion in the cerebral arteries. To search for genetic factors associated with paediatric ischaemic stroke, the possible association between CYBA gene C242T polymorphism and the disease was evaluated. MATERIAL AND METHODS The study group consisted of 238 individuals: children with ischaemic stroke (n = 70), their biological parents (n = 118) and children without any symptoms of stroke (n = 50). The C242T polymorphism was genotyped using polymerase chain reaction - restriction fragment length methodology. To evaluate the possible association between polymorphism and stroke, the transmission disequilibrium test and the case-control method were applied. RESULTS The C242 allele was transmitted more frequently than 242T (62.2% vs. 37.8%) but observed frequencies did not differ significantly from expected (p = 0.10). There were also no significant differences in allele and genotype distribution between patients and control subjects (patients: CC - 50.0%, CT - 38.6%, TT - 11.4% vs. controls: CC - 52.0%, CT - 36.0%, TT - 12.0%). CONCLUSIONS The study did not show that the C242T polymorphism of the CYBA gene is a risk factor of ischaemic stroke in children.

Polymorphisms of genes encoding coagulation factors II, V, VII, and XIII in relation to pediatric ischemic stroke: family-based and case-control study.

Background:The investigation of a possible association between the FII, FV, FVII, and FXIII genes polymorphisms and pediatric ischemic stroke (IS). Methods:The study group consisted of 392 individuals, including 81 children with IS, their biological parents (n=162), and 149 control children. The polymorphisms were genotyped using polymerase chain reaction-restriction fragments length polymorphism method. The relation between analyzed polymorphisms and the disease was tested by 2 independent methods: family-based association test—transmission/disequilibrium test (TDT) and classic case-control model. Results:We did not observe any preferential distribution of any analyzed allele from parents to the affected children. For the FVII gene polymorphism, there was a trend toward a higher frequency of the R allele. In a case-control model, the differences between the patients and controls in the frequency of the Q allele, Q allele carriers, and RR homozygotes lay close to the border of statistical significance (P=0.08). There were no significant differences in genotype and allele distribution between patients and controls in case of other polymorphisms. Conclusions:Analyzed polymorphisms of coagulation factors are not significant determinants of pediatric IS in the studied population; however, these findings require a confirmation in a larger group of participants.

Methylenetetrahydrofolate reductase gene A1298C polymorphism in pediatric stroke--case-control and family-based study.

Moderate hyperhomocysteinemia is one of the risk factors of pediatric stroke. Methylenetetrahydrofolate reductase (MTHFR) is an important enzyme, which regulates homocysteine metabolism, and some polymorphisms of gene encoding this enzyme are associated with a decreased activity of the enzyme. The aim of the study was to assess an association between the A1298C polymorphism and pediatric stroke. We also evaluated a possible synergistic effect of A1298C and C677T polymorphisms of this gene. The study group consisted of 88 children after ischemic stroke, 142 of their parents and 111 controls. The A1298C polymorphism was genotyped using the restriction fragment length polymorphism method. We used 2 study designs: a case-control model and a family-based association test. The Statistica 7.1 and EpiInfo 6 softwares were used in all analyses. We did not observe any statistically significant differences either in the transmission of the A allele in the family-based test or in the frequency of the A allele in the patients group compared with the controls. We also did not notice any significant additive or synergistic effects between the A1298C and C677T polymorphisms. An analysis of the results obtained in this study and a critical review of previously published studies indicate that the A1298C polymorphism of the MTHFR gene is not related to ischemic stroke in children.

Stabbing Headache in an 8-Year-Old Girl: Primary or Drug Induced Headache?

The occurrence of stabbing headaches in children requires a thorough diagnostic approach that excludes secondary headaches. The organic background should be taken into consideration when alarming symptoms occur, such as a purely 1-sided location, a change in the character of the headache, or possibly a link to physical activity. The current study describes the case of an 8-year-old girl who suffered short-lasting stabbing headache attacks. The headaches with increasing intensity and frequency started 1 month before her hospitalization and were usually preceded by physical activity (dancing, running). The pain, which was located in the right supraorbital region, lasted 1 second and occurred several times during the day. No associated symptoms were observed. In addition, the girl suffered from allergic rhinitis and was on antiallergic treatment (levocetirizine, fluticasone nasal spray). On admission she was in good general condition, and a pediatric and neurologic examination revealed no abnormalities. Her brain MRI was normal. The initial diagnosis was that the patient was suffering from primary stabbing headaches. However, during a follow-up visit 4 months later, a relationship was observed between the cessation of the headache attacks and the discontinuation of an antihistaminic drug. Six months later, the girl remained headache free. In cases involving differential diagnoses of stabbing headaches, it is important to consider the adverse reactions of the drugs used.