Dual Switch in Lipid Metabolism in Cervical Epithelial Cells during Dysplasia Development Observed Using Raman Microscopy and Molecular Methods

Cellular lipid metabolism is significantly transformed during oncogenesis. To assess how dysplasia development influences lipid cellular metabolisms and what is the molecular background behind it, cervical epithelial cells of 63 patients assigned to seven groups (based on the cytological examination and HPVhr test results) were studied using a multimethodological approach including Raman microscopy and molecular methods. The consistent picture obtained studying the lipid content, cell inflammation, SREBF1 gene methylation (hence SREBP1 inhibition) and level of mitochondrial DNA copies (indirectly the number of mitochondria) showed that changes in lipid metabolism were multidirectional. Cells from patients classified as mildly dysplastic (LSIL) exhibited a unique behavior (the highest level of inflammation and SREBF1 methylation, the lowest lipid content and mitochondrial DNA). On the contrary, cells from severe dysplastic (HSIL) and cancer (SCC) groups showed the opposite characteristics including the lowest SREBF1 gene methylation as well as the highest level of mitochondrial DNA and lipid cellular concentration (for HSIL/HPVhr+ and SCC groups). Following dysplastic progression, the lipid content decreases significantly (compared to the control) for mildly abnormal cells, but then increases for HSIL/HPVhr+ and SCC groups. This intriguing dual switch in lipid metabolism (reflected also in other studied parameters) on the way from normal to squamous carcinoma cells is of potential diagnostic interest.

Short Communication: An association analysis between one missense polymorphism at the SREBF1 gene and milk yield and composition traits in goats

Manunza, A., Zidi, A., Fernández-Cabanás, V. M., Jordana, J., Carrizosa, J., Belaifa, E., Urrutia, B., Polvillo, O., González-Redondo, P., Amills, M. and Serradilla, J. M. 2012. Short Communication: An association analysis between one missense polymorphism at the SREBF1 gene and milk yield and composition traits in goats. Can. J. Anim. Sci. 92: 167–173. Sterol regulatory element binding transcription factor 1 (SREBF1) regulates the expression of genes involved in the biosynthesis of fatty acids and cholesterol. Herewith, we have sequenced the near-complete coding region and part of the 3′UTR of the goat SREBF1 gene. In doing so, we have detected a missense c.353C>T polymorphism causing a proline to leucine substitution at position 118 (P118L). An association analysis with milk composition traits recorded in Murciano-Granadina goats only revealed a statistical tendency linking SREBF1 genotype and milk omega-3 fatty acid content. The lack of significant associations suggests that the P118L substitution does not involve a functional change.

The pattern of development for gene expression of sterol regulatory element binding transcription factor 1 in pigs

Sterol regulatory element-binding transcription factor 1 (SREBF1) has been implicated as a key regulator of adipocyte differentiation and lipid metabolism. The pattern of SREBF1 gene expression in different growth stages and the relation with adipose deposition is studied. Fifteen female Duroc × Landrace × Yorkshire pigs in five groups, each group of three pigs at live weight 1, 30, 50, 70 and 90 kg, were used to study the developmental gene expression of SREBF1 in the subcutaneous adipose tissue by means of semi-quantitative RT-PCR. The results showed that porcine SREBF1 mRNA was present in a very low concentration at birth and continually increased to the highest expression at 90 kg growth stages, SREBF1 mRNA levels increased as pigs grew and deposited fat from 1 to 90 kg live weights (P < 0.05). The present data indicated a close positive correlation between the levels of SREBF1 gene expression and the fat deposition rate in pigs (P < 0.05).