Humaniin – väike peptiid, suured ülesanded? Ülevaateartikkel humaniini-nimelisest peptiidist

Aastal 2001 kirjeldati esimest korda humaniini-nimelist peptiidi, mis võib olla esimene nn mitokondriaalne signaalmolekul. Praeguseks on kõnealusel peptiidil kirjeldatud mitmeid positiivseid omadusi: antiapoptootiline toime, tsütoprotektsioon mitmete mehhanismide kaudu. Peptiidi seostatakse vanusega seotud haigustega, näiteks diabeedi ja ateroskleroosiga. Artiklis on tutvustatud humaniini kui peptiidi, millest loodetakse potentsiaalset siirdemeditsiinilist läbimurret.Eesti Arst 2017; 96(6):328–33

Acute effects of methcathinone and manganese in mice: A dose response study

An intravenously injectable illicit drug made by mixing pseudoephedrine, potassium permanganate, vinegar and water, yielding methcathinone (Mcat) and manganese (Mn), induces an extrapyramidal syndrome with parkinsonism, dystonia, gait and balance disorders similar to manganism. Although the cause of the syndrome is largely attributed to Mn, the interaction of the drug's individual components is not known and the role of Mcat is possibly underestimated. Aim of the present study was to analyze dose-dependent behavioral effects of the mixture and its two main active components Mcat and Mn in an acute setting and determine the lethal doses of each substance. Three groups of C57BL/6 mice were injected intraperitoneally with (1) the drug mixture containing 10, 25, 50, 100 or 150 mg of Mcat and respectively 1.6, 3.8, 6.9, 17.1 and 22.6 mg of Mn per kilogram of body weight; (2) 10, 25, 50, 100, 150, 200 or 300 mg of racemic Mcat/kg of body weight; (3) MnCl2 10, 25 or 50 mg/kg of body weight. Locomotor activity of the animals, various signs and time of death were recorded. Lower doses (10 and 25 mg/kg) of Mcat had a clear motor activity stimulating effect and this was clearly dose-dependent. High doses of Mcat produced epileptic seizures in 74% of the animals and became lethal with the highest doses. Similarly, the mixture had a clear dose-dependent stimulating effect and the higher doses became lethal. The LD50 of the pseudoephedrine mixture was 110.2 mg of Mcat/kg and for pure Mcat 201.7 mg/kg. Mn did not prove to be lethal in doses up to 50 mg/kg, but had a strong dose dependent inhibitory effect on the animals’ behavior. Our data reveal that both Mn and Mcat have a significant role in the toxicity of the mixture

Increased striatal VMAT2 binding in mice after chronic administration of methcathinone and manganese

Intravenous use of a psychostimulant drug containing methcathinone (ephedrone) and manganese causes an irreversible extrapyramidal syndrome in drug abusers. We aimed to reproduce the syndrome in mice to evaluate dopaminergic damage. C57/B6 mice were intraperitoneally injected once a day with the study drug or saline for a period of 27 weeks. Motor activity was recorded in an automated motility-box. After 13 and 27 weeks of treatment, ex vivo digital autoradiography was performed using [11C]dihydrotetrabenazine ([11C]DTBZ). After 27 weeks of treatment [11C]DTBZ autoradiography demonstrated a significant increase in the striatum-to-cerebellum binding ratio compared with saline treated controls. At the same time point, there was no evident change in motor activity. Increased [11C]DTBZ binding may indicate vesicular monoamine transporter type 2 (VMAT2) function is altered. The lack of extrapyramidal symptoms in animals could be attributed to low dosing regimen or high metabolic rate

Genetic variants in humanin nuclear isoform gene regions show no association with coronary artery disease.

ObjectiveCoronary artery disease contributes to noncommunicable disease deaths worldwide. In order to make preventive methods more accurate, we need to know more about the development and progress of this pathology, including the genetic aspects. Humanin is a small peptide known for its cytoprotective and anti-apoptotic properties. Our study looked for genomic associations between humanin-like nuclear isoform genes and coronary artery disease using CARDIoGRAMplusC4D Consortium data.ResultsLookup from meta-analysis datasets gave single nucleotide polymorphisms in all 13 humanin-like nuclear isoform genes with the lowest P value for rs6151662 from the MTRNR2L2 gene including the 50 kb flanking region in both directions (P-value = 0.0037). Within the gene region alone the top variant was rs78083998 from the MTRNR2L13 region (meta-analysis P-value = 0.042). None of the found associations were statistically significant after correction for multiple testing. Lookup for expression trait loci in these gene regions gave no statistically significant variants

Effect of Chronic Valproic Acid Treatment on Hepatic Gene Expression Profile in Wfs1 Knockout Mouse

Valproic acid (VPA) is a widely used anticonvulsant and mood-stabilizing drug whose use is often associated with drug-induced weight gain. Treatment with VPA has been shown to upregulate Wfs1 expression in vitro. Aim of the present study was to compare the effect of chronic VPA treatment in wild type (WT) and Wfs1 knockout (KO) mice on hepatic gene expression profile. Wild type, Wfs1 heterozygous, and homozygous mice were treated with VPA for three months (300 mg/kg i.p. daily) and gene expression profiles in liver were evaluated using Affymetrix Mouse GeneChip 1.0 ST array. We identified 42 genes affected by Wfs1 genotype, 10 genes regulated by VPA treatment, and 9 genes whose regulation by VPA was dependent on genotype. Among the genes that were regulated differentially by VPA depending on genotype was peroxisome proliferator-activated receptor delta (Ppard), whose expression was upregulated in response to VPA treatment in WT, but not in Wfs1 KO mice. Thus, regulation of Ppard by VPA is dependent on Wfs1 genotype