Effect of crossing C57BL/6 and FVB mouse strains on basal cytokine expression.

C57BL/6 is the most often used laboratory mouse strain. However, sometimes it is beneficial to cross the transgenic mice on the C57BL/6 background to the other strain, such as FVB. Although this is a common strategy, the influence of crossing these different strains on homeostatic expression of cytokines is not known. Here we have investigated the differences in the expression of selected cytokines between C57BL/6J and C57BL/6JxFVB mice in serum and skeletal muscle. We have found that only few cytokines were altered by crossing of the strains. Concentrations of IL5, IL7, LIF, MIP-2, and IP-10 were higher in serum of C57BL/6J mice than in C57BL/6JxFVB mice, whereas concentration of G-CSF was lower in C57BL/6J. In the skeletal muscle only the concentration of VEGF was higher in C57BL/6J mice than in C57BL/6JxFVB mice. Concluding, the differences in cytokine expression upon crossing C57BL/6 and FVB strain in basal conditions are not profound.

Correlations between polymorphisms in genes coding elements of dopaminergic pathways and body mass index in overweight and obese women.

INTRODUCTION: Dopamine is considered to be crucial for food craving and intake, drug abuse and electrical brain stimulation. Increased levels of dopamine occur after energy intake in the dorsal striatum. In the ventral tagmental area, dopamine is responsible for motivation. There is a natural synaptic dopamine level, and as a result its activity is controlled by density of receptors, amount of released neurotransmitter, and defectiveness of re-uptake by specific transporters. In our study, we wanted to investigate if there is a correlation between mean BMI values and VNTR polymorphisms in SLC6A3 (rs28363170) and DRD4 genes. MATERIAL AND METHODS: Chosen gene fragments were amplified using polymerase chain reaction on the DNA template obtained from 506 women. The products of the reaction were electrophoresed and visualised in 3% agarose gel. The genotyping data was analysed with Kruskal-Wallis tests (p 〈 0.05). RESULTS: In the case of SLC6A3, statistically significant differences in mean BMI were found in the group of obese women (p 〈 0.05) but not for the whole population of women with normal weight or with overweight (p 〉 0.05). The mean BMI was higher for the SS genotype than for combined LL and LS genotypes. The difference in mean BMI values for variants of DRD4 was significant for the whole studied population and in the obese group (p 〉 0.05), and the higher value was correlated with the presence of a variant with seven or more repeats of 48 bp motif. CONCLUSIONS: When the two analysed polymorphisms were combined, the spread between the mean BMI values became greater than for single genes. This suggests that the effect on body mass of these two polymorphisms may combine and cause hypo-functionality of the dopaminergic reward system.