59 research outputs found
Altered adipocyte differentiation and unbalanced autophagy in type 2 Familial Partial Lipodystrophy: an in vitro and in vivo study of adipose tissue browning
Type-2 Familial Partial Lipodystrophy is caused by LMNA mutations. Patients gradually lose subcutaneous fat from the
limbs, while they accumulate adipose tissue in the face and neck. Several studies have demonstrated that autophagy is
involved in the regulation of adipocyte differentiation and the maintenance of the balance between white and brown
adipose tissue. We identified deregulation of autophagy in laminopathic preadipocytes before induction of
differentiation. Moreover, in differentiating white adipocyte precursors, we observed impairment of large lipid droplet
formation, altered regulation of adipose tissue genes, and expression of the brown adipose tissue marker UCP1.
Conversely, in lipodystrophic brown adipocyte precursors induced to differentiate, we noticed activation of autophagy,
formation of enlarged lipid droplets typical of white adipocytes, and dysregulation of brown adipose tissue genes. In
agreement with these in vitro results indicating conversion of FPLD2 brown preadipocytes toward the white lineage,
adipose tissue from FPLD2 patient neck, an area of brown adipogenesis, showed a white phenotype reminiscent of its
brown origin. Moreover, in vivo morpho-functional evaluation of fat depots in the neck area of three FPLD2 patients by
PET/CT analysis with cold stimulation showed the absence of brown adipose tissue activity. These findings highlight a
new pathogenetic mechanism leading to improper fat distribution in lamin A-linked lipodystrophies and show that
both impaired white adipocyte turnover and failure of adipose tissue browning contribute to disease.We thank FPLD2 patients for donating biological samples. We thank the Italian
Network for Laminopathies and the European Consortium of Lipodystrophies
(ECLip) for support and helpful discussion. We thank Aurelio Valmori for the
technical support. The studies were supported by Rizzoli Orthopedic Institute
“5 per mille” 2014 project to MC, AIProSaB project 2016 and Fondazione Del
Monte di Bologna e Ravenna grant 2015–2016 “New pharmacological
approaches in bone laminopathies based on the use of antibodies neutralizing
TGF beta 2” to GL. GL is also supported by PRIN MIUR project 2015FBNB5Y.S
Evaluation of skin absorption of drugs from topical and transdermal formulations
ABSTRACT The skin barrier function has been attributed to the stratum corneum and represents a major challenge in clinical practice pertaining to cutaneous administration of drugs. Despite this, a large number of bioactive compounds have been successfully administered via cutaneous administration because of advances in the design of topical and transdermal formulations. In vitro and in vivo evaluations of these novel drug delivery systems are necessary to characterize their quality and efficacy. This review covers the most well-known methods for assessing the cutaneous absorption of drugs as an auxiliary tool for pharmaceutical formulation scientists in the design of drug delivery systems. In vitro methods as skin permeation assays using Franz-type diffusion cells, cutaneous retention and tape-stripping methods to study the cutaneous penetration of drugs, and in vivo evaluations as pre-clinical pharmacokinetic studies in animal models are discussed. Alternative approaches to cutaneous microdialysis are also covered. Recent advances in research on skin absorption of drugs and the effect of skin absorption enhancers, as investigated using confocal laser scanning microscopy, Raman confocal microscopy, and attenuated total reflectance Fourier-transform infrared spectroscopy, are reviewed
A peony-leaves-derived liquid corrosion inhibitor: protecting carbon steel from NaCl
A liquid mixture was developed from waste peony leaves through a zero-waste chemical/biological process. The inhibition effect of different concentrations of peony leaves derived solution (0-3 vol.%, PLS0-3) on C1010 carbon steel in 3.5 wt.% NaCl was investigated over time using electrochemical measurements. Chemical analyses were performed to reveal the main compounds of this inhibitor. Surface analyses together with water contact angle measurements were employed to study the characteristics of the steel surface affected. Semi-empirical calculations with PM3 method were used to find the relationship between molecular structure and inhibiting effect of PLS. The inhibitor was stable over time and its main active ingredients were C19H27N4O10P and C17H16N3O9P that adsorb onto the steel surface, block cathodic active sites, make the surface hydrophobic, decrease the surface free energy, and facilitate the formation of a passive layer. A good correlation was found between experimentally determined inhibition efficiency and theoretically calculated properties of PLS
Table5_Single cell RNA sequencing reveals human tooth type identity and guides in vitro hiPSC derived odontoblast differentiation (iOB).pdf
Over 90% of the U.S. adult population suffers from tooth structure loss due to caries. Most of the mineralized tooth structure is composed of dentin, a material produced and mineralized by ectomesenchyme derived cells known as odontoblasts. Clinicians, scientists, and the general public share the desire to regenerate this missing tooth structure. To bioengineer missing dentin, increased understanding of human tooth development is required. Here we interrogate at the single cell level the signaling interactions that guide human odontoblast and ameloblast development and which determine incisor or molar tooth germ type identity. During human odontoblast development, computational analysis predicts that early FGF and BMP activation followed by later HH signaling is crucial. Here we generate a differentiation protocol based on this sci-RNA-seq analysis to produce mature hiPSC derived odontoblasts in vitro (iOB). Further, we elucidate the critical role of FGF signaling in odontoblast maturation and biomineralization capacity using the de novo designed FGFR1/2c isoform mini binder scaffold C6. Using computational tools, we show on a molecular level how human molar development is delayed compared to incisors. We reveal that enamel knot development is guided by FGF and WNT in incisors and BMP and ROBO in the molars, and that incisor and molar ameloblast development is guided by FGF, EGF and BMP signaling, with tooth type specific intensity of signaling interactions. Dental ectomesenchyme derived cells are the primary source of signaling ligands responsible for both enamel knot and ameloblast development.</p
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