Cytological evaluation of bone marrow smears stained by May-Grünwald Giemsa method was performed. The smears came from 20 fallow deer (Dama dama) 3 days old divided into 2 groups each consisting of 10 animals. The experimental group (E) received intramuscularly selenium and vitamin E at a dose of 3.0 ml (tocopherol acetate – 50 mg, sodium selenite – 0.5 mg, solvent - 1 ml) in the 3rd day of age. The control group (C) did not receive any supplementation or placebo. For hematological analyzes blood was collected three times: on 0, 15th and 25th day of the experiment. Serum concentration of selenium and vitamin E was determined using high perfor- mance liquid chromatography and glutathione peroxidase activity (GSH-Px) by kinetic method. On the 15th day after supplementation, a statistically significant increase in the percentage of erythroblastic cell line was observed in bone marrow smears. At that time, the increase in GSH-Px activity in the E group was also observed, reaching the value of 165.3 U/gHb, which was statisti- cally significant. The percentage of proerythroblasts (8.23% in group E and 5.02% in group C) differed significantly between groups at the 25th day after supplementation. This study revealed that supplementation of selenium and vitamin E resulted in an increase in the number of erythro- cytes to an average of 13.5 (˟ 10¹²/l) in the experimental group on 25th day with a significant increase in hemoglobin to 193 g/l in the experimental group.

Cell culture transplantation is very promising in the treatment of various diseases. Cells obtained from a number of sources have been analysed to provide a basis for further studies in the area of regenerative medicine. The objective of the study was to compare morphological and phenotypic changes in cat adipose tissue and bone marrow cell cultures from the first to fifth passages. Adipose tissue and bone marrow were used to obtain cell cultures (coming from 3 cats) using standard methods with own modification. Phenotype changes were monitored by CD-marker identification and CD pan-keratin. The cytogenetic analysis was performed on 50 metaphase plates of cell cultures from the first to fifth passage. Cytogenetic assays showed that the adipose tissue cell culture (ATCC) at all passages was more stable than the bone marrow cell culture (BMCC).

Telomerase reverse transcriptase (TERT) vectors were transfected into bone marrow mesen- chymal stem cells (BMSCs) which were then cultured and selected to establish TERT-BMSC cell lines whilst sequencing BMSCs and TERT-BMSCs via transcriptome in this study to explore their regulatory mechanism and effect on osteogenic differentiation after TERT ectopic expres- sion in sheep BMSCs. After sequencing and analysing differential genes, PI3K/Akt signalling pathway related to osteogenic differentiation was investigated. Western blot was used before and after applying the PI3K/Akt signalling pathway inhibitor LY294002 to detect protein expression levels of AKT and p-AKT. On the twenty-first day of osteogenic differentiation, RT-qPCR and Western blot were used to detect mRNA and protein expression levels of RUNX2 and OPN and alizarin red staining was utilised to analyse calcium salt deposition. Results showed that pro- tein expression levels of AKT and p-AKT were significantly up-regulated, mRNA and protein expression levels of RUNX2 and OPN increased and calcium salt deposition increased after ectopic expression of TERT. After applying LY294002, the protein expression of AKT and p-AKT was down-regulated, mRNA and protein expression levels of RUNX2 and OPN were reduced and calcium salt deposition was reduced. These results confirmed the stable integration and expression of the exogenous TERT gene in BMSCs to promote the differentiation of BMSC osteoblasts, which may be mediated by the PI3K/Akt signalling pathway.

Emerging researches in humans, pigs and mice, highlighted that estrogen plays a pivotal role in self-renewal and differentiation of bone marrow mesenchymal stem cells (BMSCs). The present study aimed at evaluating effects of 17 beta-estradiol (E2) on proliferation and apoptosis of canine-derived bone marrow mesenchymal stem cells (cBMSCs) in vitro. The results showed that E2 supplementation at the concentration of 10-11 M promoted the proliferation of cBMSCs by CCK-8 assay and RT-qPCR analysis for the proliferation-related genes, with proliferating cell nuclear antigen (PCNA), cyclin-D1 (CCND1) being up-regulated and cyclin-dependent kinase inhibitor 1B (CDKN1B) being down-regulated. Contrarily, analysis of fluorescence-activated cell sorting (FACS) and RT-qPCR demonstrated that E2 supplementation above 10-11 M had inhibitory effects on the proliferation of cBMSCs and induced apoptosis. Intriguingly, cBMSCs still possessed the capability to differentiate into osteoblasts and adipocytes with 10-11 M E2 addition. Taken together, this study determined the optimal culture condition of cBMSCs in vitro, and has important implications for further understanding the regulatory effect of E2 on the self-renewal of cBMSCs, which are helpful for the clinical application of BMSCs.