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Ectopic Liver Tissue Formation in Rats with Induced Liver Fibrosis
Get PDFIntroduction: The possible alternative approach to whole-organ transplantation is a cell-based therapy, which can also be used as a "bridge" to liver transplantation. However, morphological and functional changes in the liver of patients suffering from chronic liver fibrosis and cirrhosis restrict the effectiveness of direct cell transplantation. Therefore, extra hepatic sites for cell transplantation, including the spleen, pancreas, peritoneal cavity, and subrenal capsule, could be a useful therapeutic approach for compensation of liver functions. However, a method of transplantation of hepatocytes into ectopic sites is needed to improve hepatocyte engraftment. Previously published data has demonstrated that mouse lymph nodes can support the engraftment and proliferation of hepatocytes as ES and rescue Fah mice from lethal liver failure. Thus, the aim of the study was to evaluate the engraftment of i.p. injected allogeneic hepatocytes into extra hepatic sites in albino rats with chemically induced liver fibrosis (LF). Materials and methods: Albino rats were randomly divided into 4 groups: (1) intact group (n = 18); (2) rats with induced LF (n = 18); (3) rats with induced LF and transplanted with hepatocytes (n = 18); (4) as a control, rats were treated with cyclosporine A only (n = 18). In order to prevent an immune response, groups 2 and 3 were subjected to immunosuppression by cyclosporine A (25 mg/kg per day). LF was induced using N-nitrosodimethylamine (NDMA), i.p., 10 mg/kg, three times a week for 4 weeks and confirmed by histological analysis of the liver samples. Hepatocytes transplantation (HT) was performed two days after NDMA exposure cessation by i.p. injection of 5×106 freshly isolated allogeneic hepatocytes. Liver function was assessed by quantifying blood biochemical parameters (ALT, AST, GGT, total protein, bilirubin, and albumin) at 1 week, 1 month, and 2 months after hepatocytes transplantation (HT). To confirm a hepatocytes’ engraftment, we conducted immunohistochemical staining against HepPar1.Results: We observed a 30% mortality rate among rats with LF within 1 week after NDMA exposure cessation, while 100% of animals with HT survived. ALT, AST, and GGT activities and bilirubin levels were markedly elevated in blood samples of LF rats compared to the control animals. However, HT significantly improved ALT, AST, and GGT activity as well as bilirubin levels. We also observed decreased levels of total protein and albumin in the blood serum of rats with LF, while HT normalized these parameters. At the same time, we have not detected any statistical differences of the studied parameters in the group 4, which was treated with Cyclosporine A only, compared with the intact animals. HepPar1 immunohistochemical staining of the different tissue sections demonstrated the presence of engrafted hepatocytes, mainly within enlarged Peyer\u27s patches (aggregated lymphoid nodules in the lowest portion of the small intestine).Conclusion: The results of our study provide evidence that HT improves animal survival and liver functions. One potential reason for these results is that ectopic hepatic mass inside the Peyer\u27s patches can rescue rats from liver failure
Pharmacokinetic Properties of Cytokines in Their Targeted Delivery Based on Autologous Erythrocyte Pharmacocytes
Get PDFIntroduction. Using autologous erythrocytes as drug carriers for targeted delivery of cytokines to the sites of inflammation could potentially provide new opportunities for treatment of patients with purulent diseases. The targeted characteristic of erythrocytes is associated with the nature of purulent inflammation, where a large amount of erythrocytes is phagocytized and drugs encapsulated into the erythrocytes could be easily released. On the other hand, autologous erythrocytes meet all the criteria for the ideal drug carrier. They are nontoxic, not immunogenic, and able to bear a large number of drug molecules while preserving an original conformation of the drugs. Thus, in this study, we aimed to analyze pharmacokinetic profiles of IL-1? encapsulated into erythrocytes’ ghosts (pharmacocytes) in comparison to intravenously injected free IL-1?.Material and methods. Albino rats were randomly divided into two groups, each group receiving a different kind of IV injection via the tail vein. Group A (control) received 500 µg of free IL-1?, and group B received an injection of 1 ml of pharmacocytes loaded with 500 µg of test substance. At fixed time points after injection (15, 30, 60, 180, 540, 720, and 1,440 minutes) serum samples were collected. Homogenates of liver, spleen, lung, heart, kidney, and adipose tissue were obtained 24 hours after injections. Concentration of the tested substance in the collected organs and blood plasma were measured by ELISA. Results. We have observed an increased half-life period (T1/2) for encapsulated IL-1? compared to the control. T1/2 for free IL-1? was one hour, while administration of loaded pharmacocytes allowed the half-life period to increase by more than 15 fold (1,043.40 ± 137.92 min) preserving high level of IL-1? activity in the blood samples up to 24 hours. The increased time of IL-1? presence in the body when administered in the form of pharmacocytes could be explained by reduction of elimination constant (Cel) by 1.6 fold, and clearance (CLel) by more than 100 fold. We also observed an increased concentration of IL-1? in liver, spleen, and lung over at least 24 hours. When administered in free form, IL-1? disappeared from these organs within 6 hours.Conclusions. Pharmacocytes have shown to improve pharmacokinetic profiles of IL-1? by increasing the half-life period of the cytokine, reducing its clearance and elimination as well as increasing the deposition of the drug in liver, spleen and lungs. These data suggest that pharmacocytes be effective drug carriers for targeted delivery of cytokines to the sites of inflammation and have a potential for improving the treatment outcomes of purulent diseases
Pharmacogenetic research in Kazakhstan
Get PDFIntroduction: Pharmacogenomics is an emerging field of medicine that combines genetics and pharmacology. Pharmacogenomic research is relatively new in Kazahkstan, but, in recent years, significant progress has been made in this field. The National Scientific Laboratory for Biotechnology has launched several government-funded research projects focused on finding genetic markers that determine susceptibility to various drugs. Another goal of pharmacogenetic research in the laboratory is to find the pharmacogenomic markers that target cardiovascular diseases, accounting for allelic frequencies in selected genes in the Kazakh population. In addition, pharmacogenomic testing kits allow patients to choose the drug dosage. For example, the drug Warfarin has been developed within the framework of the "Technology Commercialization Project,” funded jointly by the Ministry of Education and Science of the Republic of Kazakhstan and the World Bank.Material and methods: The pharmacogenomic studies were conducted using the real-time PCR and direct DNA sequencing. DNA was isolated from venous blood or buccal cells, collected from patients.Results: To date, we have identified the most promising areas of research in the field of pharmacogenomics in Kazakhstan. The allelic frequencies of a number of polymorphisms in the Kazakh population have been calculated (CYP2C9, CYP2C19, CYP3A4, VKORC1, CYP4F2, GGCX, CYP2D6, CYP1A2, NAT2, GSTP1, SLC47A1). A unique repository of DNA samples was established and is being replenished during the implementation of aforementioned projects. Development of the testing kit for individual selection of Warfarin dosage is nearing completion. A patent, named "Method of Selection Based Dose Warfarin Genotyping for the Kazakh Population" has been recently obtained. An application for another patent, titled "Express Method of Correction of Warfarin Dosing, Based on Real-time PCR" has received positive evaluation. The results of domestic pharmacogenomic studies will allow a more rational selection of drugs and their dosage regimens specific to the Kazakh population
Intra-articular injection of synovium-derived mesenchymal stem cells and hyaluronic acid promote regeneration of massive cartilage defects in rabbits
Get PDFIntroduction: The purpose of this study was to investigate whether intra-articular injection of synovium-derived mesenchymal stem cells (SD MSCs) with low molecular weight hyaluronic acid (HA) could promote regeneration of massive cartilage in rabbits.Material and methods: The SD MSCs were harvested from the knees of 10 Flemish giant rabbits, expanded in culture, and characterized. A reproducible 4-mm cylindrical defect was created in the intercondylar groove area using a kit for the mosaic chondroplasty of femoral condyle COR (De Puy, Mitek). The defect was made within the cartilage layer without destruction of subchondral bone. Two weeks after the cartilage defect, SD MSCs (2 × 106 cell/0.15 ml) were suspended in 0.5% low molecular weight HA (0.15 ml) and injected into the left knee, and HA solution (0.30 ml) alone was placed into the right knee. Cartilage regeneration in the experimental and control groups were evaluated by macroscopically and histologically at 10, 30, and 60 days.Results: On day 10, after intra-articular injection of SD MSCs, we observed an early process of cartilage regeneration in the defect area. Histological studies revealed that cartilage defect was covered by a thin layer of spindle-shaped undifferentiated cells and proliferated chodroblasts. In contrast, an injection of HA did not induce reparation of cartilage in the defect area. At 30 days, macroscopic observation showed that the size of cartilage defect after SD MSC injection was significantly smaller than after HA injection. Histological score was also better in the MSC- treated intercondylar defect. At 60 days after MSC treatment, cartilage defect was nearly nonexistent and looked similar to an intact cartilage.Conclusion: Thus, intra-articular injection of SD MSCs can adhere to the defect in the intercondylar area, and promote cartilage regeneration in rabbits
Biochemical Characterization of Mycobacterium tuberculosis DNA Repair Enzymes – Nfo, XthA and Nei2
Get PDFIntroduction: Tuberculosis (TB) is a human disease caused by Mycobacterium tuberculosis (Mtb). Treatment of TB requires long-term courses of multi-drug therapies to eliminate subpopulations of bacteria, which sometimes persist against antibiotics. Therefore, understanding of the mechanism of Mtb antibiotic-resistance is extremely important. During infection, Mtb overcomes a variety of body defense mechanisms, including treatment with the reactive species of oxygen and nitrogen. The bases in DNA molecule are susceptible to the damages caused by reactive forms of intermediate compounds of oxygen and nitrogen. Most of this damage is repaired by the base excision repair (BER) pathway. In this study, we aimed to biochemically characterize three Mtb DNA repair enzymes of BER pathway.Methods: XthA, nfo, and nei genes were identified in mycobacteria by homology search of genomic sequences available in the GenBank database. We used standard methods of genetic engineering to clone and sequence Mtb genes, which coded Nfo, XthA and Nei2 repair enzymes. The protein products of Mtb genes were expressed and purified in Escherichia coli using affinity tags. The enzymatic activity of purified Nfo, XthA, and Nei2 proteins were measured using radioactively labeled DNA substrates containing various modified residues. Results: The genes end (Rv0670), xthA (Rv0427c), and nei (Rv3297) were PCR amplified using genomic DNA of Mtb H37Rv with primers that contain specific restriction sites. The amplified products were inserted into pET28c(+) expression vector in such a way that the recombinant proteins contain C-terminal histidine tags. The plasmid constructs were verified by sequencing and then transformed into the Escherichia coli BL21 (DE3) strain. Purification of recombinant proteins was performed using Ni2+ ions immobilized affinity column, coupled with the fast performance liquid chromatography machine AKTA. Identification of the isolated proteins was performed by protein mass spectrometry by ion trap tandem MS/MS on nLC-ESI-Ion-Trap platform. Biochemical characterization of DNA repair protein-catalyzed activity was carried out by measuring apurinic/apyrimidinic endonuclease, DNA glycosylase, exonuclease, and 3\u27-repair diesterase functions. In addition, effect of the opposite base and the influence of metal ion cofactors were measured. Conclusion: Results of the ongoing study will help us define the role of DNA repair enzymes in the emergence of mutations in the mycobacterial genome and, possibly, the origins of multi-drug resistance in mycobacteria.
Health benefits of new symbiotic “NAR”
Get PDFIntroduction: The immune-modulatory effects of synbiotics and their ability to reduce free radical levels may be useful for functional food that is able to be active throughout whole period of colonization of the gastrointestinal tract.The aim of the present study was to investigate the immune-modulatory and antioxidant effects of the synbiotic product "N?R," a probiotic beverage.Methods: The presence of IL-2, IL-4, IL-6, IL-8, IL-10, ?TNF, ?IFN, Ig A, Ig M, and Ig E was studied in vitro using a solid immunosorbent analysis. The total antioxidant activities of superoxide dismutase and glutathione reductase were determined by a spectrophotometry using the Sigma-Aldrich sets.Results: Studies of the immune-modulatory properties of the synbiotic product NAR showed 1.7 fold increase of ?INF levels (p<0.01) in blood after consumption of the synbiotic product “NAR” in comparison to control values, whereas the concentrations of IL-4 and Ig E decreased 2.0 times (treatment: 9.3; control: 18.7; p<0.01) and 1.3 times (p<0.1), respectively. The consumption of the synbiotic product “NAR” caused an increase in the proportion of ?INF/IL 4 (treatment: 15.4; control: 4.4; p<0.01), which indicates a reduction in functional activity of Th2-type lymphocytes in comparison with the function of Th1 cells.Our study showed a high level of the total antioxidant activity of the synbiotic product (67.4 mmol/ml). The antioxidant activity of the intact cells of consortium (15.3 mM/ml), which was the basis for the preparation of the symbiotic product, is several times lower than the activity observed in the symbiotic samples.Expression of SOD is one of the mechanisms of antioxidant stress radicals inactivation by bacteria. The analysis identified a superoxide dismutase activity of synbiotic product (1.42 U/mg protein). A glutathione reductase activity of the synbiotic product was elevated (0.06 U/ml). Conclusion: The majority of the inflammatory mediators found in the blood after the consumption of symbiotic product NAR were inflammatory mediators that activate a cellular component of the resistance. Moreover, the symbiotic product has a high antioxidant activity.
Immunocytochemical Characterization of Alzheimer’s Disease Hallmarks in APP/PS1 Transgenic Mice Treated with a New Anti-Amyloid-β Vaccine
Get PDFIntroduction: APP/PS1 double-transgenic mouse models of Alzheimer’s disease (AD), which overexpress mutated forms of the gene for the human amyloid precursor protein (APP) and presenilin 1 (PS1), have provided robust neuropathological hallmarks of an AD-like pattern at early ages. This study aimed to characterize immunocytochemical patterns of the AD mouse brain, which is treated with the EB101 vaccine, as a model for human AD.Material and methods: In this novel vaccine, a new approach has been taken to circumvent past failures with A? vaccines by judiciously selecting an adjuvant consisting of a physiological matrix embedded in liposomes, composed of naturally occurring phospholipids (phosphatidylcholine, phosphatidylglycerol, and cholesterol).Results: Our findings showed that the administration of amyloid-?1?42 (A?) and sphingosine-1-phosphate emulsified in liposome complex (EB101) to APP/PS1 mice before the onset of A? brain deposition (at 7 weeks of age) and/or at an older age (35 weeks of age) can be effective in both halting the progression and clearing the AD-like neuropathological hallmarks. In addition, passive immunization with EB101 did not activate inflammatory responses from the immune system and astrocytes. Consistent with a decreased inflammatory background, the basal immunological interaction between the T cells and the affected areas (hippocampus) in the brain of treated mice was notably reduced.Conclusion: These results provide strong evidence that immunization with the EB101 vaccine prevents and attenuates AD neuropathology in this type of double-transgenic mice
Effect of Probiotic Consortium on the Local Inflammatory Process in Chronic Periodontitis
Get PDFIntroduction: Inflammatory periodontal disease is one of the major concerns of researchers and clinicians, because it can lead to tooth loss and an increased risk of systemic pathologies, even at the age of 35. The purpose of this study was to determine the effects of gelatin-based probiotic consortium on the local and general factors of inflammation in rats with chronic periodontitis.Methods: The study object was a complex of probiotic bacteria based in an odourless 6% gelatin plate with neutral flavour. A cellular biomass of the consortium consists of following lactobacilli: Lactobacillus casei subsp. pseudoplantarum, Lactobacillus caseisubsp.casei, L.fermentum, and L. helveticus. The viable cell number was 2.5 x 109 CFU/ml. The model of chronic periodontitis was reproduced in the white random-bred rats that weighed 160-220g, by keeping them on a low-protein diet. After three months, symptoms associated with medium and severe chronic periodontitis were observed in the rats. Application was carried out on the oral mucosa of rats 1 time per day for 14 days. The stickers lacking consortium of microorganisms were used as the placebo. The "Solcoseril" gel was chosen as a comparator. The hematologic, biochemical, and morphological characteristics were investigated.Results: A complete clearance of periodontal pockets was observed during an objective examination of the experimental group rats on the 14th day of the experiment. Moreover, a gingival mucous turned pink, and there were no cyanosis tissues. The local changes were accompanied by improvement in hematological parameters, such as a reduction of blood eosinophilia and neutrophilia, and a recovery of the white blood cells number to the normal degree within the group that received the probiotic complex. A decrease of the acute plethora of microvasculature was observed morphologically as a result of the treatment. There were signs of basal layer activation of the stratified squamous epithelium with a merger of the acanthosis outgrowths and a formation of the fibrotic nodules. Biochemical investigations did not show significant changes in the indicators.Conclusions: In the settings of the chronic periodontitis model, the use of gelatin-based probiotic consortium consisting of Lactobacillus casei subsp. pseudoplantarum, Lactobacillus caseisubsp.casei, L.fermentum, L. helveticus. at 2.5 x 109 CFU/ml viable cell numbers lead to the reduction of the local inflammatory manifestations of the periodontitis in 14 days of treatment.
Effects of Antioxidants and Vitamins on the Proliferation of Human Diploid Cells
Get PDFIntroduction: Microelements, essential nutrients that are needed in small amounts including minerals such as calcium, zinc, iron and other vitamins (A, B, C, and etc.), are macronutrients necessary for a healthy life.The role of micronutrients in vivo is well known, and there are several publications that have examined the effects of micronutrients on genomic stability. Furthermore, a number of vitamins and microelements are substrates and/or cofactors in metabolic pathways, which regulate DNA synthesis and/or repair and gene expression.A deficiency in such nutrients may result in disruption of genomic integrity and alterations in DNA methylation patterns, linking cellular nutrition with change in gene expression. For example, lack of vitamin C is known to cause increased DNA oxidation and chromosomal damage. Vitamin A, as well as other micronutrients, have a protective effect, whereas higher concentrations are associated with increased DNA damage.Ubiquinone (coenzyme Q10) and dihydroquercetin are used in therapy as antioxidant compounds and electron carriers, which reduce lipid peroxidation of cell membranes. However, previous studies indicate that various ubiquinone analogs may cause a divergent effect on oxidative stress and oxidative phosphorylation.The aim of our study was to investigate the effect of vitamins A and C, coenzyme Q10, and dihydroquercetin on the proliferative potential of cultured human embryonic diploid fibroblasts (M-22).Methods: In the first series of experiments, nontoxic concentrations of vitamins for the cells were identified using MTT assay.Results: Vitamins A and C, dihydroquercetin of 1µM, and coenzyme Q10 of 5µM were nontoxic for human skin fibroblasts.In the second series of experiments, cell cultivation was carried out with nontoxic concentrations. A vitamin C concentration of 1µM for 7 consecutive passages increased the proliferation index (PI) compared to the control. Thus, the average PI in the experiments was 2.3, whereas in the control, it was 1.7. Similar results were obtained when dihydroquercetin was added to the growth medium. However, further cultivation of cells in the presence of vitamin C decreased PI to 1.4, while the control value remained the same. Daily examination revealed no morphological changes in the cell culture, but the cell growth had slowed significantly. The use of vitamin A in a nontoxic concentration of 1 µM reduced PI to 0.7 in the first passage, so further culturing of human cells with vitamin A was stopped.Conclusion: Studies examining the effect of different combinations of microelements on the proliferation of human diploid cells and the expression of specific proteins in them are still being conducted.
Genotype frequencies of polymorphic MDR1 variants in the Kazakhstani population
Get PDFIntroduction: Statins appear to be handled by an ATP-dependent membrane transporter and three SNPs (C1236T (rs1128503), G2677T (rs2032582), and C3435T (rs1045642), which capture the common genetic variation at this locus. Individuals, who carry the T allele at each SNP (i.e., the T-T-T haplotype), have higher systemic exposure to simvastatin.A triallelic thymine (T) - guanine (G) - adenine (A), which is a point mutation at nucleotide 2677 in exon 22, leads to ABCB1 in a non-synonymous codons (GCT alanine, TCT serine, threonine ACT) at position 893 in a cytoplasmic loop of ATP-dependent membrane transporters.Methods: Blood samples from healthy individuals were collected in the Republican Diagnostic Center, Astana, Kazakhstan. The research samples included 461 healthy people. Genomic DNA was extracted from peripheral blood using the ‘salting out’ procedure. For the MDR1 exon 21, 2677G?T/A (Ala893Ser/Thr) polymorphism was genotyped by PCR sequencing by the use of dye-terminator (ABI 3730xl sequencer). Results: The GG allele appeared in 23% of samples, the GA in 6.7%, the GT in 44%, the non-G heterozygote in 4.5%, and the non-G homozygote in 18%. These results are consistent with previously published data. Importantly, the frequency of 2677T alleles in our group was 15.4%. This represents the lowest frequency of this allele compared to published data in different populations. The frequency of the 2677T allele in Asians and Caucasians varies from 38 to 62%, and is 15% for African Americans. On the other hand, the 2677A allele frequency in the Japanese varies from 15 to 22%, and in Caucasians from 2% and 4%. The 2677A allele frequency has been found in 4.6% of samples. Conclusions: Our study further emphasizes differences between various Asian populations and the importance of repeating this genetic study in different ethnic groups