Eating Behaviors and Body Composition Among College Freshmen: The Effect of Dietary and Commensal Culture on Biological Outcomes

As new college students become autonomous eaters, they may independently develop behaviors related to food that fulfill both biological and cultural purposes. I report here on the results of a biocultural, mixed-methods study of 21 students’ first term of college residence. Interview data and anthropometric measurements permit exploration of the interaction between a shift in participants’ cultural surroundings, physical condition, and food-related thoughts and actions. Participants’ goals of fulfilling their student responsibilities and maintaining social relationships predominantly dictated when, where, and what they ate, while their level of satisfaction with these behaviors was associated with whether their actions were consistent with personal definitions of “healthy.” Participants who demonstrated a conscious effort to eat in a healthy manner generally expressed the highest satisfaction with their food-related behaviors, but did not all experience similar changes in their physical conditions. Because participants’ goals influenced their satisfaction with their eating behaviors, they may affect participants’ behaviors in the future. Continued research should investigate how the goals that individuals articulate but do not act on during this period in their life course may influence their health and behaviors later in their lives

Regulation of CREB activation by p38 mitogen activated protein kinase during human primary erythroblast differentiation.

Among the molecular events underlying erythroid differentiation, we analyzed the signalling pathway leading to cAMP response element binding (CREB) nuclear transcription factor activation. Normal donor blood light density cells differentiated to pro-erythroblasts during the proliferative phase (10 days) of the Human Erithroblast Massive Amplification (HEMA) culture, and to orthochromatic erythroblasts, during the differentiative phase (4 additional days) of the culture. Since erythropoietin was present all over the culture, also pro-erythroblasts left in proliferative medium for 14 days continued their maturation without reaching the final steps of differentiation. p38 Mitogen Activated Protein Kinase (p38 MAPK) and CREB maximal activation occurred upon 4 days of differentiation induction, whereas a lower activation was detectable in the cells maintained in parallel in proliferative medium (14 days). Interestingly, when SB203580, a specific p38 MAPK inhibitor, was added to the culture the percentage of differentiated cells decreased along with p38 MAPK and CREB phosphorylation. All in all, our results evidence a role for p38 MAPK in activating CREB metabolic pathway in the events leading to erythroid differentiation

Evidence for the cost of reproduction in humans : high lifetime reproductive effort is associated with greater oxidative stress in post-menopausal women

Life history theory predicts trade-offs between reproductive effort and maternal survivorship in energy-restricted environments. However, empirical evidence for the positive association between maternal mortality and reproductive effort from energetically challenged human populations are mixed and physiological mechanisms that may underlie this association are poorly understood. We hypothesized that increases in aerobic metabolism during repeated periods of pregnancy and lactation result in increased oxidative stress that may contribute to somatic deterioration, vulnerability to illness, and accelerated aging. We therefore predicted that lifetime gravidity and parity would be related to levels of biomarkers of oxidative stress, as well as antioxidative defence enzymes in post-menopausal women. Our hypothesis was supported by positive linear associations between levels of 8-OHdG, a biomarker of DNA oxidative damage (β = 0.21, p = 4 pregnancies per lifetime) had 20% higher levels of 8-OHdG and 60% higher levels of Cu-Zn SOD compared to women with lower gravidity and parity (<4 pregnancies per lifetime). Our results present the first evidence for oxidative stress as a possible cost of reproductive effort in humans

E-cigarettes fluids trigger molecular and morphological response in oral fibroblasts

Electronic-cigarettes (e-cigarettes) have been recently advertised as a safe alternative to the traditional ones and a possible smoking cessation tool. This electronic device was designed to transform a solution of variable compounds (some of them approved as food additives), in an inhalable aerosol. However, their safety is still not fully know (Lerner et al. 2016). The cytotoxicity of the fluids on human gingival fibroblasts (HGFs) was demonstrated on a previous study by Sancilio et al. (2016) where the occurrence of oxidative stress and apoptosis was found following the exposure to nicotine containing fluids. The aim of this study was to investigate the HGF biological response to e-cigarettes liquids (with and without nicotine) and to clarify the molecular mechanisms driving the cytotoxicity exerted by fluids themselves. To this purpose, cells were treated with e-cigarette fluids containing nicotine (final concentration 1mg/mL) and the equivalent volume of a fluid without nicotine, for times up to 48 h. Lactate Dehydrogenase Assay (LDH), electronic microscopy analysis, collagen I production, flow cytometry lysosome compartment evaluation and western blotting LC3 (microtubule-associated protein 1A/1B-light chain 3) expression were performed. Fluids containing nicotine exerted cytotoxicity as demonstrated by the increased levels of LDH, in parallel to the formation of numerous vacuoles in the cytoplasm, as well as a decrease in collagen I production and an augmented LC3 II expression which characterized autophagy occurrence In conclusion E-cigarette fluids (with and without nicotine) trigger modification ultrastructure, collagen production and lysosomal compartment in HGFs, suggesting an involvement in the pathogenesis of oral diseases

Adhesion of human gingival fibroblasts/Streptococcus mitis co-culture on the nanocomposite system Chitlac-nAg

10noComposite materials are increasingly used as dental restoration. In the field of biomaterials, infections remain the main reason of dental devices failure. Silver, in the form of nanoparticles (AgNPs), ions and salt, well known for its antimicrobial properties, is used in several medical applications in order to avoid bacterial infection. To reduce both bacterial adhesion to dental devices and cytotoxicity against eukaryotic cells, we coated BisGMA/TEGDMA methacrylic thermosets with a new material, Chitlac-nAg, formed by stabilized AgNPs with a polyelectrolyte solution containing Chitlac. Here we analyzed the proliferative and adhesive ability of human gingival fibroblasts (HGFs) on BisGMA/TEGDMA thermosets uncoated and coated with AgNPs in a coculture model system with Streptococcus mitis. After 48 h, HGFs well adhered onto both surfaces, while S. mitis cytotoxic response was higher in the presence of AgNPs coated thermosets. After 24 h thermosets coated with Chitlac as well as those coated with Chitlac-nAg exerted a minimal cytotoxic effect on HGFs, while after 48 h LDH release raised up to 20 %. Moreover the presence of S. mitis reduced this release mainly when HGFs adhered to Chitlac-nAg coated thermosets. The reduced secretion of collagen type I was significant in the presence of both surfaces with the co-culture system even more when saliva is added. Integrin β1 localized closely to cell membranes onto Chitlac-nAg thermosets and PKCα translocated into nuclei. These data confirm that Chitlac-nAg have a promising utilization in the field of restorative dentistry exerting their antimicrobial activity due to AgNPs without cytotoxicity for eukaryotic cells.openopenCataldi, Amelia; Gallorini, Marialucia; Di Giulio, Mara; Guarnieri, Simone; Mariggiò, Maria Addolorata; Traini, Tonino; Di Pietro, Roberta; Cellini, Luigina; Marsich, Eleonora; Sancilio, SilviaCataldi, Amelia; Gallorini, Marialucia; Di Giulio, Mara; Guarnieri, Simone; Mariggiò, Maria Addolorata; Traini, Tonino; Di Pietro, Roberta; Cellini, Luigina; Marsich, Eleonora; Sancilio, Silvi

Imaging flow cytometry: a subtle and depth analysis of molecular mechanisms

The ImageStreamX is an innovative instrument that takes advantage of imaging flow cytometry, a novel technique that combines the speed, statistical power, and fluorescence sensitivity of flow cytometry with the functional insights of high resolution microscopy to give the most insightful cell analysis possible [1]. Among the wide range of applications, in our laboratory we study the human gingival fibroblasts (HGF) response to resin-based materials commonly used in dentistry, in terms of membrane molecule expression, intracellular signal transduction and cell death and apoptosis. Our experimental model is thought to resemble the oral cavity by cultivating the cells in the presence of saliva flow and microrganisms commonly present in vivo. As regards surface antigens expression, IDEAS image analysis software allows to virtually quantitate anything you can see using the software package’s numerous predefined fluorescence and morphologic parameters. Regarding the signal transduction, the IDEAS software package quantifies nuclear translocation events by automatically correlating the images of the transcription factor and the nucleus using the Similarity score. As of cell death and expression, Image StreamX can perform any standard flow cytometry assay, i.e. Annexin-V/PI one, with the added value of visual confirmation

Effects of a new nanocomposite system on Human Gingival Fibroblasts/Streptococcus mitis co-culture

In the broad field of biomaterials, Bisphenol A glycidylmethacrylate (BisGMA)/triethyleneglycol dimethacrylate (TEGDMA) thermosets are frequently used for dental restoration (Lehtinen et al 2008), but infections due to bacterial adhesion remain the main reason of dental devices failure. In order to avoid biofilm formation on the components used for restoration and to reduce cytotoxicity against eukaryotic cells, a new material with antimicrobial properties was developed. Indeed, silver nanoparticles (n-Ag), which have well-known antimicrobial properties, were stabilized with a polyelectrolyte solution-Chitlac (lactose-modified chitosan) and was used to coating methacrylic thermosets (Travan et al, 2011). This study was aimed at evaluating the in vitro biological response of human gingival fibroblasts (HGFs)/Streptococcus mitis co-colture to this nanocomposite system. HGFs were obtained from fragments of healthy marginal gingival tissue, co-cultured with the clinical strain of S. mitis and treated for 24 -48 h with thermosets (uncoated or coated with Chitlac or Chitlac n-Ag). Cytotoxicity was evaluated by LDH assay; cell morphology and adhesion were verified by means of SEM and optical microscopy; cell migration was studied by a modified Boyden chamber and finally IL-6 and PGE2 secretion were detected by ELISA assays. In vitro results showed that in our co-culture model, which mimics the microenvironment of the oral cavity, the nanocomposite material does not exert cytotoxic effect towards HGFs that are able to adhere and migrate. The secretion of IL-6 is significant, but PGE2 production is minimal suggesting that IL-6 production is not related to an inflammatory response. Basing on its good biocompatibility we suggest this new tool useful for the realization of dental devices

Effects of methacrilyc thermosets coated with Silver-polysaccharide nanocomposite on HGFs adhesion in a S. mitis co-culture system

Silver based medical products have been proven to be effective in retarding and preventing bacterial growth, being silver reported to control infections since ancient times (1). In the field of dentistry, the use of silver ions/nanoparticles has been explored to counteract bacteria in resins and implants, as silver can destroy bacterial cell walls by reacting with the thiol groups (–SH) of proteins exposed to the extracellular portion of the bacterial membrane. Conversely, eukaryotic cells lack these exterior binding sites, so nanoparticles are supposed to interact with them only upon metal internalization (2). To reduce both bacterial adhesion to dental devices and cytotoxicity against eukaryotic cells, we coated BisGMA/TEGDMA methacrylic thermosets with a new material, Chitlac-nAg, formed by stabilized silver nanoparticles with a polyelectrolyte solution containing Chitlac. Here we analyzed the proliferative and adhesive ability of human gingival fibroblasts (HGFs) on BisGMA/TEGDMA thermosets uncoated and coated with AgNPs in a co-culture model system with Streptococcus mitis. After 48 h, HGFs well adhered onto both surfaces, while S. mitis cytotoxic response was higher in the presence of AgNPs coated thermosets. After 24 h thermosets coated with Chitlac as well as those coated with Chitlac-nAg exerted a minimal cytotoxic effect on HGFs, while after 48 h LDH release rised up to 20%. Moreover, the presence of S. mitis reduced this release mainly when HGFs adhered to Chitlac-nAg coated thermosets. The reduced secretion of collagen type I was significant in the presence of both surfaces even more when saliva is added. Integrin β1 localized closely to cell membranes onto Chitlac-nAg thermosets and PKC α translocated into nuclei. These data confirm that Chitlac-nAg thermosets have a promising utilization in the field of restorative dentistry exerting their antimicrobial activity due to AgNPs without cytotoxicity for eukaryotic cells.This work was supported by grants from MIUR FIRB 2010 and MIUR PRIN-2009

Effect of Chitlac-nAg on Streptococcus mitis internalization into human gingival fibroblasts

The surfaces of the oral cavity are always exposed to a broad variety of microor- ganisms able to form biofilms (Filoche et al, 2010) characterized by microbial com- munities that are organized as a network of cell-to-cell interactions. Streptococci are the predominant bacterial population of the oral environment and S.mitis in particular is the first colonizer of the oral biofilm (Di Giulio et al, 2013). Silver-based medical products have been proven to be effective in retarding and preventing bacterial growth. In order to prevent silver nanoparticles aggregation, a lactose-modified chitosan has been set up and resulted effective in stabilizing colloidal solution of nanoparticles (Chitlac-nAg) (Travan et al, 2009). Since many bacteria are able to internalize into eukaryotic cells, in our study we have investigated both the intracellular signaling governing S. mitis internalization into HGFs and the biological effect of ChitlacnAg on eukaryotic and prokaryotic cells in a co-culture model system. The internalization of S. mitis into HGFs is due to F-actin cytoskeleton reorganization and reduced expression within the cell. Immunofluorescence shows actin polymerization at invasion sites along with vinculin increased expression and spot organization. Vinculin is an adaptor protein that regulates the adhesion of integrin receptors to actin cytoskeleton. In presence of S. mitis an increment of integrin β1 and FAK expression, responsible for the entrance of the microorganism in HGFs is consistent, as revealed by electron microscopy analysis. This adhesion and uptake proteins profile is the same in the presence of saliva as well as bacteria uptake. When Chitlac-nAg is administred to cell culture the expression of all four proteins decreases and Ag nano- particles are recognized within the cells. Further, in presence of Ag nanoparticles the low amount of FAK is almost localized at nuclear level. In presence of Ag and S.mitis, the expression of all four proteins is increased, with respect to control, and F-actin cytoskeleton rearranged, while a raised number of bacteria is shown. This effect is mit- igated by the presence of saliva in cell culture, which probably prevents bacteria entry into the cell. These results let us hypothesize that Chitlac-nAg, developing its bacteri- cidal action could represent a good component of tooth paste and mouthwash