Ameliorative effect of Arabic gum Acacia and mori extracts in streptozotocin-induced diabetic rats: implications of Cas-3 and TGF-ß.

OBJECTIVE: Arabic gum Acacia (AG) is rich in fiber which improves lipid metabolism besides its antioxidant effect. Folium mori (FM) is a widely used herb due to its immunomodulatory, antimicrobial, and antioxidant activity. In the current study, we explore the antidiabetic, anti-inflammatory, as well as antioxidant activities of AG and FM in Streptozotocin (STZ), induced diabetic rats. MATERIALS AND METHODS: STZ diabetic rats were orally administrated with metformin and/or a combination of AG and FM for 4 weeks. Glycemic levels, Serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST), cholesterol, triglycerides, urea, and creatinine were determined. Malondialdehyde (MDA), glutathione peroxidase (GPx), and Superoxide dismutase (SOD) were also evaluated. Gene expression and profile as well as immunohistopathological were also evaluated. RESULTS: The results elicited no toxicological profile of both AG and FM. Plasma glucose level was decreased starting from 1st week to 4th week; besides, there was an improvement in glycated hemoglobin, insulin, and fructosamine. Liver and kidney damage markers were decreased in both AG and FM-treated rats. A significant increase in the antioxidant defense system and a decrease in oxidative stress markers were also observed. Gene expression analysis in brain tissues revealed a significant decrease in Interleukin beta 1 (IL-ß1), Caspase 3 (Cas-3), and Transforming growth factor beta (TGF-ß). CONCLUSIONS: Oral treatment of metformin with AG and FM in STZ-injected rats could ameliorate protective pathways and can be one of the promising oral anti-diabetic herbal agents.

[Blastocyst Hatching in Humans].

The human oocyte is surrounded by the zona pellucida­an elastic, transparent extracellular matrix consisting of specific glycoproteins. The zona pellucida is preserved after fertilization and surrounds the developing human embryo for a few days. The embryo needs to get out of the zona pellucida before implantation to establish cell contacts between the trophectoderm and endometrial epithelium. The release of the embryo from the zona pellucida is carried out at the stage of the blastocyst and called zona hatching. During zona hatching the blastocyst breaks the zona pellucida and performs active movements to escape through a gap formed in the zona. While microscopic description of zone hatching is well known, biochemical and cytological basis of zone hatching remains poorly understood. The break of the zona pellucida occurs under the influence of two forces: mechanical pressure of the growing blastocyst on the zone and chemical dissolution of the zone material with secreted lytic enzymes. There is only one paper (Sathananthan et al., 2003), which describes the specialized cells in the trophectoderm that locally dissolve the zona pellucida, promoting the emergence of the hole for blastocyst release. Taking into account the singleness of the paper and the absence of further development of this subject by the authors in the following decade, the existence of specialized cells for zone hatching should be assumed with great care. Lytic enzymes, secreted by cells of the trophectoderm for dissolving the zona pellucida, are different. Depending on the species of the mammal, different classes of proteases participate in the zone hatching process: serine proteases, cysteine proteases, metalloproteinases. Proteases, secreted by human trophectoderm, are not described. The mechanisms of the active movement during blastocyst hatching are investigated to a lesser degree. Only the involvement of the cytoskeleton of trophectoderm cells in the mechanism of blastocyst compression was shown, and the participation of desmosomes in the coordinated change in the form of trophectoderm cells during compression is suggested. This review summarizes literature data on the possible mechanisms of zone hatching in the development of human embryos, obtained in experiments in vitro, as well as in animal models.

[Hereditary muscular dystrophy: bioengineering approaches to muscle fiber repair].

Restoration of disturbed functions of the organs and tissues is the main task of contemporary genetic and cellular biotechnology, including genetic and cellular therapy. Duchenne dystrophy, one of the most widespread human genetic diseases, is at the same time the most extensively studied from the viewpoint of both genetic and histological changes leading to muscle fiber degeneration. Although many studies carried out on models, recognized analogous to Duchenne dystrophy, gave hopeful results, clinical tests with the use of developed methods gave no expected success and the rate of mortality from this disease amounts to 100%. Based on the world experience and analysis of the authors' data, possible influence of the intensity of regeneration on success of genetic and cellular therapy has been considered.

Aseptic technology of vitrification of human pronuclear oocytes using open-pulled straws.

BACKGROUND: The aim of this study was to compare the viability of human pronuclear oocytes subjected to vitrification using cooling by direct submerging of open-pulled straws in liquid nitrogen versus vitrification by cooling of open-pulled straws located inside a closed 0.5 ml straw (aseptic system). METHODS: Two- and three-pronuclei stage oocytes (n=114) were cryopreserved in super-open-pulled straws by vitrification in 20% ethylene glycol +20% dimethylsulphoxide (DMSO) + osmotic active and neutral non-permeable cryoprotectants with a four-step exposure in 20, 33, 50 and 100% vitrification solution for 2, 1 and 1 min, and 30-50 s, respectively at room temperature, and plunging into liquid nitrogen. Oocytes of group 1 (n=42) were rapidly cooled at a speed of 20,000 degrees C/min by direct plunging of open-pulled straws into liquid nitrogen. Oocytes of group 2 (n=44) were first located in 0.5 ml straws, which were closed at both sides by metal balls, and then plunged into liquid nitrogen. This method resulted in a cooling speed of 200 degrees C/min. For both groups, oocytes were thawed rapidly at a speed of 20 000 degrees C/min using an identical protocol. Oocytes subsequently were expelled into a graded series of sucrose solutions (1.0, 0.75, 0.5, 0.25 and 0.12 mol/l) at 2.5 min intervals. RESULTS: Oocyte development up to expanded blastocyst stage after in vitro culture was 15% in group 1, 14% in group 2 and 29% in an untreated control group. CONCLUSION: The deposition of human pronuclear oocytes in open-pulled straws which are placed inside a hermetically closed container guarantees a complete isolation of oocytes from liquid nitrogen and avoids potential contamination by pathogenic microorganisms. The combination of direct plunging of this container into liquid nitrogen and rapid warming makes this process as efficient as conventional vitrification.

[Differentiation of muscle fibers in mdx mice after ballistic transfection of cDNA of the human dystrophin gene]. / Differentsirovka myshechnykh volokon myshei MDX posle ballisticheskoi transfektsii kDNK gena distrofina cheloveka.

Changes in morphological dimensions of MDX mouse myofibres in M. rectus femoris were recorded after ballistic transfection (BT) with pHSADys and pVMMDys plasmids containing cDNA of the full-length human dystrophin gene. The dystrophin expression was observed by an immunomorphological procedure with P6 antibody and PAP method. Dystrophin positive (dyst+) myofibres were divided into two types, with a typical dystrophin expression under sarcoplasma membrane and an atypical expression through the whole sarcoplasm, respectively. The share of atypical dyst+ myofibres was seen to rise during the experiment from 27%, at 2-3 weeks after BT, up 84% by 2 months after BT. The atypical dyst+ myofibres usually underwent destruction. At the same time, the share of entire dyst+ myofibres decreased from 17 to 2-5% by 2 months. Morphological dimensions of the myofibres (square in mkm2, perimeter, smallest and largest diameters) were calculated with the help of computer analyser. The middle square of both types of dyst+ myofibres was larger than that of dyst- myofibres, both in BT target M. rectus femoris and in the same contralateral muscle, but never exceeded the value of middle square of C57B1 mouse myofibres in the same muscle. The form of dyst+ myofibres was not modified by the dystrophin expression. The nuclei of dyst+ myofibres remained in the central region of sarcoplasm. A conclusion is made that BT of human dystrophin gene inside MDX mouse myofibres allows dystrophin gene expression and enlargement of the dyst+ myofibres. Dystrophin expression is not able to induce a complete and stable differentiation of striated muscle of adult MDX mice.

[Expression of the human dystrophin gene in mdx mouse skeletal muscles after ballistic transfection]. / Ekspressiia gena distrofina cheloveka v skeletnykh myshtsakh myshei mdx posle ballisticheskoi transfektsii.

"Gene-gun" ballistic transfection (BT) was used to deliver genetic constructs pMLVDy and pHSADy containing full-length cDNA of the dystrophin gene to musculus quadriceps remoris and musculus gluteus of mdx mice, which represent a natural model of Duchenne muscular dystrophy. Clusters of dystrophin-positive muscular fibers (DPMF) were immunocytochemically detected in sites exposed to BT. The average number of DPMF was 2% by the 17th day and 3% by the 60th day after BT with pMLVDy, whereas the number of revertant DPMF was 0.2% in control mice (without BT). When pHSADy was used, the average number of DPMF was 3% 20 days after BT. In this case, dystrophin was uniformly spread though the myoplasm in 3% of cells and produced a slight signal in separate regions under the sarcolemma in 10% of muscle fibers. The number of revertant DPMF increased to 0.6% after BT with naked particles and to 2.8% after BT with the marker lacZ gene, in both bombarded and contralateral legs. The number of DPMF in the corresponding muscles of the contralateral leg significantly increased and reached 2.8% by the 60th day after BT with pMLVDy and 6.7% by the 20th day after BT with pHSADy. Human dystrophin gene cDNA was detected in all skeletal muscles, heart, intestine, tongue, and brain by polymerase chain reaction (PCR) three weeks after BT. Immunoblot analysis showed that normal 427-kDa human dystrophin was synthesized in muscles of mdx mice. The results suggest applicability of BT for delivery of dystrophin constructs into muscles.

Bacterial beta-galactosidase and human dystrophin genes are expressed in mouse skeletal muscle fibers after ballistic transfection.

Ballistic transfection, based on cell and tissue bombardment by the tungsten and gold microparticles covered with the gene DNA, was used for the delivery of a bacterial beta-galactosidase and a full-length cDNA copy of the human dystrophin genes into mouse skeletal muscles. CMV-lacZ, SV40-lacZ, LTR-lacZneo and full-length cDNA dystrophin (pDMD-1, approximately 16 kb) in eukaryotic expression vector pJ OMEGA driven by mouse leukaemia virus promotor (pMLVDy) were used throughout the studies. Musculus glutaeus superficialis of C57BL/6J and quadriceps femoris of mdx male mice were opened surgically under anesthesia and bombarded by means of the gene-gun technique originally developed by us. Different mixtures of gold and tungsten particles at ratios of 4:1, 1:1, 1:4 were applied. X-gal assay revealed marked beta-gal activity, both in total muscles and whole muscle fibers on histological sections, up to three months after transfection. The most intensive staining was observed after SV40-lacZ delivery. No staining was detected with LTR-lacZneo DNA as well as in untreated muscles. The higher tungsten particle concentration in the bombardment mixture correlated with more intense X-gal staining. At the gold/tungsten ratio of 1:4 the microparticles penetrated the musculus glutaeus superficialis and transfected the underlying musculus glutaeus medius as well. Immuno-cytochemical assay for human dystrophin revealed dystrophin positive myofibers (DPM) in the bombarded area up to two months after transfection. The proportion of DMP varied from 2.5% on day 17 up two 5% on day 60 after bombardment compared to only 0.5% in the control mdx mice. These results suggest the applicability of particle bombardment for gene delivery into muscle fibers.

[Metallonucleoliposome complexes as a vehicle for gene delivery to mouse skeletal muscles in vivo]. / Metallonukleoliposomnye kompleksy kak sredstvo dostavki genov v skeletnye myshtsy myshi in vivo.

A simple new method for preparing plasmid DNA and preformed zwitterionic liposome complexes is proposed. The ability of these metallonucleoliposome complexes to serve as a vehicle for gene delivery to mammalian cells in vivo was studied. A high level of expression of the reporter gene introduced was observed in mouse skeletal muscles in vivo.

[The ballistic transfection of mammalian cells in vivo]. / Ballisticheskaia transfektsiia kletok mlekopitaiushchikh in vivo.

The method of ballistic transfection initially proposed for genetic transformation of plants was used for animal cells in vitro and in situ. The method consists in bombarding the transfected cells with microparticles of heavy metals carrying foreign DNA. Having penetrated in the cell nucleus, the microparticles transport the introduced gene. Successful genetic transformation of the cultured mouse cells and fish embryos was realized and this allowed to study mammalian cells in situ. The studies performed allowed us to demonstrate expression of the reporter genes of chloramphenicol acetyltransferase, galactosidase and neomycin phosphotransferase in the mouse liver, mammary gland and kidney explants, in the liver and cross-striated muscle of mouse and rat in situ and in developing mouse embryos at the stages of two-cell embryo, morula and blastocyst. All these genes were introduced by ballistic transfection. In the liver and cross-striated muscle the transgene activity was found within two-three months after transfection. Thus, the ballistic introduction of the foreign genes in the cells in situ was demonstrated and this opens possibilities for the use of this method in gene therapy. Methodical aspects of the bombarding and transfection are considered in detail and the published data on transfection and genetic transformation of mammalian cells are discussed.