In vivo skin leptin modulation after 14 MeV neutron irradiation: a molecular and FT-IR spectroscopic study

Abstract

This paper discusses gene expression changes in the skin of mice treated by monoenergetic 14 MeV neutron irradiation and the possibility of monitoring the resultant lipid depletion (cross-validated by functional genomic analysis) as a marker of radiation exposure by high-resolution FT-IR (Fourier transform infrared) imaging spectroscopy. The irradiation was performed at the ENEA Frascati Neutron Generator (FNG), which is specifically dedicated to biological samples. FNG is a linear electrostatic accelerator that produces up to 1.0 × 10(11) 14-MeV neutrons per second via the D-T nuclear reaction. The functional genomic approach was applied to four animals for each experimental condition (unirradiated, 0.2 Gy irradiation, or 1 Gy irradiation) 6 hours or 24 hours after exposure. Coregulation of a subclass of keratin and keratin-associated protein genes that are physically clustered in the mouse genome and functionally related to skin and hair follicle proliferation and differentiation was observed. Most of these genes are transiently upregulated at 6 h after the delivery of the lower dose delivered, and drastically downregulated at 24 h after the delivery of the dose of 1 Gy. In contrast, the gene coding for the leptin protein was consistently upregulated upon irradiation with both doses. Leptin is a key protein that regulates lipid accumulation in tissues, and its absence provokes obesity. The tissue analysis was performed by monitoring the accumulation and the distribution of skin lipids using FT-IR imaging spectroscopy. The overall picture indicates the differential modulation of key genes during epidermis homeostasis that leads to the activation of a self-renewal process at low doses of irradiation.

Soft and Robust Identification of Body Fluid Using Fourier Transform Infrared Spectroscopy and Chemometric Strategies for Forensic Analysis

“…The existence of thiocyanate anions (SCN − ) is reflected by the typical peak at 2057 cm −1 9 , 31 . Lipids in oral mucosa correspond to the peaks at 2943 cm −1 , 2854 cm −1 and 1743 cm −1 , which results from the symmetric and asymmetric C–H stretching and carbonyl (C=O) stretching of the ester groups, respectively 33 , 34 . Sugar moieties of glycosylated proteins, including α-amylase, show large variances in the spectral range of 1080-950 cm −1 9 , 31 .…”

New insights into the antimicrobial treatment of water on Ag‐supported solids

“…). The first peak at 1260 cm −1 corresponds to adsorbed PO 2− species on the solid surface (surface Ag atoms), the second (1520 cm −1 ) to adsorbed C–N containing species, and the third (2400 cm −1 ) to adsorbed P–H containing species, whereas the fourth peak (2880 cm −1 ) is characteristic for C–H containing species such as lipids . These results provide undisputable evidence that cellular membrane components are strongly bound on the solid surface during the antimicrobial process which leads to cell lysis.…”

“…, the two solids present several similarities but also some distinct differences, both in terms of the nature and intensity of the IR peaks observed. In particular, the spectra obtained over both solids present two broad bands, one between 1600 and 1700 cm −1 and another between 3000 and 3600 cm −1 , which correspond to the stretching mode of adsorbed water and adsorbed hydroxyls, respectively. However, the spectrum observed over the Ag/Al 2 O 3 material presents four additional IR peaks/bands centred at 1260, 1520, 2400 and 2880 cm −1 (Fig.…”

“…Figure presents the IR spectra obtained on powdered 1 wt% Ag‐supported material and alumina spheres, which have been used for the treatment of an E. coli bacterial solution. All peaks observed were identified using bibliographical data . As seen in Fig.…”

Reflections on Basic Science Studies Involving Low Doses of Ionizing Radiation

“…Thus, even though increased incidence of obesity in animals exposed to chronic low doses of low LET radiation was noted in the early 2000’s these data were not published until ten years later (Uehara, Ito et al 2010). Moreover, even though others found association between neutron exposures and leptin (Cestelli Guidi, Mirri et al 2012), no direct research into the relationship of obesity and low doses has yet been done. It is worthwhile to note that our understanding of carcinogenesis in general is still far from comprehensive – additional low dose induced carcinogenesis research could open up the doors to a new understanding of this process.…”