3D Raman imaging of systemic endothelial dysfunction in the murine model of metastatic breast cancer

It was recently reported in the murine model of metastatic breast cancer (4T1) that tumor progression and development of metastasis is associated with systemic endothelial dysfunction characterized by impaired nitric oxide (NO) production. Using Raman 3D confocal imaging with the analysis of the individual layers of the vascular wall combined with AFM endothelial surface imaging, we demonstrated that metastasis-induced systemic endothelial dysfunction resulted in distinct chemical changes in the endothelium of the aorta. These changes, manifested as a significant increase in the protein content (18 %) and a slight decrease in the lipid content (4 %), were limited to the endothelium and did not occur in the deeper layers of the vascular wall. The altered lipid to protein ratio in the endothelium, although more pronounced in the fixed vascular wall, was also observed in the freshly isolated unfixed vascular wall samples in the aqueous environment (12 and 7 % change of protein and lipid content, respectively). Our results support the finding that the metastasis induces systemic endothelial dysfunction that may contribute to cancer progression

Polymorphism of model triglycerides: infrared absorption and Raman study

Podczas pracy zbadano cztery trójglicerydy: nasycony tripalmitynian oraz trzy związki nienasycone: trioleinian (9-10 cis), trielaidynian (9-10 trans) i tripetroselinian (6-7 cis). Dla wymienionych trójglicerydów można wyróżnić formy polimorficzne: α, β’ i β dla tripalmitynianu, trioleinianu i tripetroselinianu oraz dwie formy: α i β trielaidynianu. Do badania polimorfizmu trójglicerydów można wykorzystać metody spektroskopowe, które umożliwiają rozróżnienie trójglicerydów ze względu na ich cechy charakterystyczne: nasycone lub nienasycone łańcuchy węglowe czy położenie i geometrię wiązania podwójnego. Otrzymane formy polimorficzne tripalmitynianu oraz fazę ciekłą zbadano z wykorzystaniem spektroskopii ramanowskiej oraz spektroskopii absorpcyjnej w podczerwieni. Ponadto wygenerowano widma teoretyczne najbardziej stabilnych konformerów tripalmitynianu na podstawie obliczeń kwantowo-chemicznych i chociaż nie odzwierciedlają one wyników eksperymentalnych ze względu na brak uwzględnionych oddziaływań międzymolekularnych, umożliwiają jednak otrzymanie dodatkowych wniosków na podstawie ich analizy.Pozostałe trójglicerydy: trioleinian, trielaidynian oraz tripetroselinian zbadano wykorzystując spektroskopię ramanowską. Otrzymane wyniki pozwoliły na wyznaczenie pasm, których kształt, ilość składowych oraz wzajemne stosunki intensywności pasm pozwalają na rozróżnianie polimorfów. Ponadto wykonano badanie skaningową kalorymetrią różnicową dla próbek tripalmitynianu i tripetroselinianu.Triglycerides are esters of trihydroxy alcohol glycerol. They show complicated polymorphism depending on the fatty acid structures: saturated or unsaturated acids, the position of bands associated with the double bond or cis/trans isomerism. It is generally accepted that triglycerides exist in three polymorphic forms in the order of increasing stability: α form (hexagonal), β’ form (orthorombic) and β form (triclinic).Vibrational spectroscopy is a convenient method to study the structure of triglycerides also in their metastable forms. This study presents the Raman spectra of four different monoacid triglycerides: saturated tripalmitin and three unsaturated isomeric compounds: triolein (9-10 cis), trielaidin (9-10 trans) and tripetroselinin (6-7 cis). Additionally, infrared absorption spectroscopy has been used to characterize the tripalmitin.Moreover, the experimental spectra of tripalmitin were obtained and compared to theoretical spectra of tripalmitin monomeric models. The aim of the calculations was to find general correlations between monomeric and polymorphs structural features and get some information about single monomers’ structure.Furthermore, differential scanning calorimetry (DSC) was used as the tool to interpret the transition processes of tripalmitin and tripetroselinin

The distinct phenotype of primary adipocytes and adipocytes derived from stem cells of white adipose tissue as assessed by Raman and fluorescence imaging

Spectroscopy-based analysis of chemical composition of cells is a tool still scarcely used in biological sciences, although it provides unique information about the cell identity accessible in vivo and in situ. Through time-lapse spectroscopic monitoring of adipogenesis in brown and white adipose tissue-derived stem cells we have demonstrated that considerable chemical and functional changes occur along with cells differentiation and maturation, yet yielding mature adipocytes with a similar chemical composition, independent of the cellular origin (white or brown adipose tissue). However, in essence, these stem cell-derived adipocytes have a markedly different chemical composition compared to mature primary adipocytes. The consequences of this different chemical (and, hence, functional) identity have great importance in the context of selecting a suitable methodology for adipogenesis studies, particularly in obesity-related research