Phytochemical characterization and biological activity of apricot kernels' extract in yeast-cell based tests and hepatocellular and colorectal carcinoma cell lines.

ETHNOPHARMACOLOGICAL RELEVANCE: Bitter apricot kernels' extract contains a broad spectrum of biologically active substances with a lot of attention to amygdalin - cyanogenic glycoside. The extract has been used in the pharmaceutical industry for years as an ingredient of different pharmaceuticals with anti-inflammatory, antimicrobial, or regenerative properties. In traditional medicine, the bitter apricot kernels are known as a remedy for respiratory disorders and skin diseases. The apricot kernels and amygdalin are often prescribed by practitioners for the prevention and treatment of various medical conditions, including colorectal cancer. THE PRESENT STUDY AIMS: to evaluate the phytochemical composition and the potential antimutagenic, antirecombinogenic, and antitumor effect of apricot kernels' extract at very low concentrations in yeast cell-based tests and mammalian hepatocellular and colon carcinoma cell lines. MATERIALS AND METHODS: Phytochemical analysis was performed by LC-MS profiling. Reverse-phase HPLC and UV detection were applied for the determination of amygdalin quantity in the extract. Biological activity was evaluated by Zimmermann's mutagenicity and Ty1 retrotransposition test. Cytotoxic/antiproliferative activity of apricot kernels' extract was performed on four types of cell lines - HepG2, HT-29, BALB/3T3, clone A31, and BJ using the standard MTT-dye reduction assay. RESULTS: Data revealed the presence of more than 1000 compounds and 4 cyanogenic glycosides among them - Amygdalin, Deidaclin, Linamarin and Prulaurasin. The Amygdalin concentration was measured to be 57.8 µg/ml. All extract concentrations demonstrated a strong antigenotoxic, antirecombinogenic, antimutagenic, and anticarcinogenic effect in the yeast cell-based tests. High selectivity of the extract action is established among different mammalian cell lines. Normal cell line BJ is found to be resistant to the extract action. HepG2 was found to be the most sensitive to apricot kernels' action. CONCLUSION: The present study provides the first phytochemical analysis of Bulgarian bitter apricot kernels. Three new cyanogenic glycosides were reported. Evidence is obtained that the apricot kernels' extract at low concentrations is not able to induce some of the events related to the initial steps of tumorigenesis. Additionally, a high selectivity of the extract action is established among different cell lines. The most sensitive cell line was found to be HepG2.

New X-chromosomal interactors of dFMRP regulate axonal and synaptic morphology of brain neurons in Drosophila melanogaster.

Fragile X syndrome is a neuro-developmental disease caused by transcriptional inactivation of the gene FMR1 (fragile X mental retardation 1) and loss of its protein product FMRP. FMRP has multiple neuronal functions which are implemented together with other proteins. To better understand these functions, the aim of this study was to reveal new protein interactors of dFMRP. In a forward genetic screen, we isolated ethyl-metanesulphonate-induced X-chromosomal modifier mutations of dfmr1. Four of them were identified and belong to the genes: peb/hindsight, rok, shaggy and ras. They are dominant suppressors of the dfmr1 overexpression wing phenotype 'notched wings'. These mutations dominantly affected the axonal and synaptic morphology of the lateral ventral neurons (LNv's) in adult Drosophila brains. Heterozygotes for each of them displayed effects in the axonal growth, pathfinding, branching and in the synapse formation of these neurons. Double heterozygotes for both dfmr1-null mutation and for each of the suppressor mutations showed robust genetic interactions in the fly central nervous system. The mutations displayed severe defects in the axonal growth and synapse formation of the LNv's in adult brains. Our biochemical studies showed that neither of the proteins - Rok, Shaggy, Peb/Hnt or Ras - encoded by the four mutated genes regulates the protein level of dFMRP, but dFMRP negatively regulates the protein expression level of Rok in the brain. Altogether, these data suggest that Rok, Shaggy, Peb/Hnt and Ras are functional partners of dFMRP, which are required for correct wing development and for neuronal connectivity in Drosophila brain.

Echinococcus granulosus strain typing in Bulgaria: the G1 genotype is predominant in intermediate and definitive wild hosts.

Addressing the genetic variability in Echinococcus granulosus is epidemiologically important, as strain characteristics may influence the local transmission patterns of zoonotic cystic echinococcosis. To classify the genotype(s) present in intermediate (pig, cattle and sheep) and definitive (jackal and wolf) hosts in Bulgaria, a DNA-based approach was used to assess parasite protoscoleces or strobiles. Genes corresponding to coding and non-coding regions of the nuclear and mitochondrial genome ( ND-1, HBX, Act II, AgB-1) were amplified by PCR and subsequently sequenced. The sequences resolved were all found to be identical to those published for the common sheep strain of E. granulosus, indicating that the G1 genotype is predominant in Bulgaria. One microvariant for ND-1 was found in the pig isolates; however no epidemiological significance was attributed to this finding.