50 research outputs found
Biophysical and biological characterization of a new line of hyaluronan-based dermal fillers: A scientific rationale to specific clinical indications
Chemico-physical and biological characterization of hyaluronan-based dermal fillers is of key importance to differentiate between numerous available products and to optimize their use. These studies on fillers are nowadays perceived as a reliable approach to predict their performance in vivo. The object of this paper is a recent line of hyaluronic acid (HA)-based dermal fillers, Aliaxin®, available in different formulations that claim a complete facial restoration. The aim of the study is to provide biophysical and biological data that may support the clinical indications and allow to predict performance possibly with respect to similar available products. Aliaxin® formulations were tested for their content in soluble HA, water uptake capacity, rheological behavior, stability to enzymatic degradation, and for in vitro capacity to stimulate extracellular matrix components production. The formulations were found to contain a low amount of soluble HA and were equivalent to each other regarding insoluble hydrogel concentration. The different crosslinking degree declared by the producer was consistent with the trend in water uptake capacity, rigidity, viscosity. No significant differences in stability to enzymatic hydrolysis were found. In vitro experiments, using a full thickness skin model, showed an increase in collagen production in the dermoepidermal junction.
Results support the claims of different clinical indications, the classification of products regarding hydro-, lift-action and the specifically suggested needle gauge for the delivery. The biological outcomes also support products effectiveness in skin structure restoration. These data predicted a better performance regarding hydro-action, tissue integration, clinical management during delivery, and a high durability of the aesthetic effect when compared to data on marketed similar products
Diarylureas: New Promising Small Molecules against Streptococcus mutans for the Treatment of Dental Caries
Dental caries is a biofilm-mediated disease that represents a worldwide oral health issue.
Streptococcus mutans has been ascertained as the main cariogenic pathogen responsible for human
dental caries, with a high ability to form biofilms, regulated by the quorum sensing. Diarylureas
represent a class of organic compounds that show numerous biological activities, including the
antimicrobial one. Two small molecules belonging to this class, specifically to diphenylureas, BPU
(1,3-bis[3,5-bis(trifluoromethyl)phenyl]urea) and DMTU (1,3-di-m-tolyl-urea), showed interesting
results in studies regarding the antimicrobial activity against the cariogenic bacterium S. mutans.
Since there are not many antimicrobials used for the prevention and treatment of caries, further
studies on these two interesting compounds and other diarylureas against S. mutans may be useful to
design new effective agents for the treatment of caries with generally low cytotoxicit
Lycopene Inhibits NF-kB-Mediated IL-8 Expression and Changes Redox and PPARγ Signalling in Cigarette Smoke–Stimulated Macrophages
Increasing evidence suggests that lycopene, the major carotenoid present in tomato, may be preventive against smoke-induced cell damage. However, the mechanisms of such a prevention are still unclear. The aim of this study was to investigate the role of lycopene on the production of the pro-inflammatory cytokine IL-8 induced by cigarette smoke and the possible mechanisms implicated. Therefore, human THP-1 macrophages were exposed to cigarette smoke extract (CSE), alone and following a 6-h pre-treatment with lycopene (0.5–2 µM). CSE enhanced IL-8 production in a time- and a dose-dependent manner. Lycopene pre-treatment resulted in a significant inhibition of CSE-induced IL-8 expression at both mRNA and protein levels. NF-kB controlled the transcription of IL-8 induced by CSE, since PDTC prevented such a production. Lycopene suppressed CSE-induced NF-kB DNA binding, NF-kB/p65 nuclear translocation and phosphorylation of IKKα and IkBα. Such an inhibition was accompanied by a decrease in CSE-induced ROS production and NOX-4 expression. Lycopene further inhibited CSE-induced phosphorylation of the redox-sensitive ERK1/2, JNK and p38 MAPKs. Moreover, the carotenoid increased PPARγ levels which, in turn, enhanced PTEN expression and decreased pAKT levels in CSE-exposed cells. Such effects were abolished by the PPARγ inhibitor GW9662. Taken together, our data indicate that lycopene prevented CSE-induced IL-8 production through a mechanism involving an inactivation of NF-kB. NF-kB inactivation was accompanied by an inhibition of redox signalling and an activation of PPARγ signalling. The ability of lycopene in inhibiting IL-8 production, NF-kB/p65 nuclear translocation, and redox signalling and in increasing PPARγ expression was also found in isolated rat alveolar macrophages exposed to CSE. These findings provide novel data on new molecular mechanisms by which lycopene regulates cigarette smoke-driven inflammation in human macrophages
Association between High Intake of Lycopene-rich Foods (Tomato, Grapefruit, Watermelon, Papaya) and Reduced Risk of Cancer
The consumption of lycopene and lycopene-rich foods, such as tomato, papaya, watermelon and grapefruit, has been associated with decreased risk of several cancers, including prostatic, lung and gastrointestinal cancers. In vitro studies demonstrated that lycopene may inhibit the growth of several types of cancer cells and provided valuable insights into the mechanisms by which lycopene exert their cellular and intracellular effects. Mechanisms implicated in the prevention of cancer incidence and progression by lycopene-rich foods include: modulation of redox activity, enzyme detoxyfication, inhibition of cell proliferation and apoptosis induction, regulation of growth factor and hormone signalling, inhibition of cell adhesion and angiogenesis, inhibition of cholesterol synthesis, immunomodulation and enhancement of gap junction communication. A good number of animal studies indicates a protective effect of pure lycopene or lycopene-rich foods on prostatic, gastro-intestinal and lung tumorigenesis. Although numerous epidemiological studies demonstrate that lycopene and lycopene-rich foods may reduce cancer risk, intervention trials establishing a direct link between lycopene and/or lycopene-rich foods and cancer prevention are still few and controversial. This review examines the experimental and clinical evidences for a preventive role of lycopene and lycopene-rich foods on cancer as well as the mechanisms of action implicated. In addition, it speculates on the interactions existing between lycopene and other bioactive food components in cancer prevention
Lycopene as a guardian of redox signalling
It has been suggested that lycopene, the major carotenoid
found in tomato, exhibits health-beneficial effects
by virtue of its antioxidant activity. However, recent literature
suggests that lycopene can actually \u201cperform\u201d
roles independent of such capacity and involving a direct
modulation of redox signalling. Reactive oxygen
species are known to act as second messengers in the
modulation of cellular signalling leading to gene expression
changes and pharmacological responses. Lycopene
may control redox-sensitive molecular targets, affecting
enzyme activities and expressions and modulating the
activation of MAPKs and transcription factors, such as
NF-\u3baB and AP-1, Nrf2