Enrico Campioli

Morphological and receptorial changes in the epididymal adipose tissue of rats subjected to a stressful stimulus.

Obesity is nowadays related to other pathological conditions such as inflammation, insulin resistance, and diabetes, but little is known about the relationship between psychological stress and adipocytes. We decided to study the expression of the translocator protein (TSPO) 18‐kDa, peroxisome proliferator‐activated receptor‐γ (PPAR‐γ), mitochondrial uncoupling protein‐1 (UCP‐1), and adipocyte morphology in the adipose tissue of rats subjected to stress conditions. In our model of stress, rats fasted for 24 h were placed in a restraint cage and then immersed vertically to the level of the xiphoid process in a water bath at 23 °C for 7 h. After that period, we removed the epididymal adipose tissues for the subsequent analysis. The optical and electron microscopy revealed that adipocytes of control rats formed a continuous epithelial‐like cell layer; on the contrary in the adipocytes of stressed rats some cells have merged together and the number of vessels formed seems to increase. Stressed adipocytes presented unilocular cells with numerous mitochondria with a morphology ranging between that of brown adipose tissue (BAT) and white adipose tissue (WAT). Interestingly, when we investigated the subcellular distribution of UCP‐1 by immunogold electron microscopy, the adipose tissue of stressed rats was positive for UCP‐1. From the immunoblot analysis with anti‐PPAR‐γ antibody, we observed an increased expression of PPAR‐γ in the adipocytes of stressed group compared with control group (P < 0.05). Stress induced the expression of TSPO 18‐kDa receptor (Bmax = 106.45 ± 5.87 fmol/mg proteins), which is undetectable by saturation‐binding assay with [3H]PK 11195 in the control group.

Polyunsaturated fatty acid levels in rat tissues after chronic treatment with dietetic oils

BACKGROUND The essential fatty acids can be helpful in the prevention of several pathologies. The purpose of this study was to quantify the major n-3 and n-6 fatty acids in tissues of rats fed with flaxseed oil and with a dietetic oil in order to evaluate how their chronic supplementation could influence the correspondent in vivo levels and to study the effectiveness of the dietetic oil compared to flaxseed oil. RESULTS Fatty acids were successfully extracted from biological samples, subjected to derivatization procedure and analysed by high-performance liquid chromatography with UV detection under gradient elution mode. The developed method showed good linearity, precision and accuracy, with recoveries ranging from 89% to 92%. Animals treated with flaxseed and dietetic oils showed enhanced levels of n-3 fatty acids compared to control groups, with significantly higher levels of eicosapentaenoic acid and docosahexaenoic acid in the brain and in the adipose tissue of the dietetic group compared to the flaxseed group. CONCLUSION The obtained data underline that the tested oils can effectively enhance the tissue levels of n-3 fatty acids and therefore they could be successfully used in the dietetic treatment of lipid-related diseases.

Evidence that isopropylthioxanthone (ITX) is devoid of anxiolytic and sedative effect

Isopropylthioxanthone (ITX) is a well-known photo-initiator in ultraviolet light-cured inks frequently used in milk packaging materials, yoghurt, ready-to-feed infant formula, and other drinks. Traces of ITX have been found in milk and, as a consequence, there was considerable interest in studying the biological activity of this molecule and its potential hazard for the human health. Although the ITX genotoxic effects have been excluded by the European Food Safety Authority (EFSA), the US Environmental Protection Agency (USEPA) is still examining its possible toxic potential depending on a dose–effect ratio. Little is known about the ITX activity on the function of the central nervous system and cerebral neurotransmitters. Using behavioural, biochemical, and electrophysiological tests, the authors have found that: (1) ITX did not exert an in vivo anxiolytic or sedative effect when administered orally to rats; (2) ITX did not affect the binding characteristics of central and peripheral benzodiazepine receptors studied in vitro; and (3) ITX did not influence the ability of γ-Aminobutyric acid (GABA) to increase the chloride channel permeability studied by patch clamp technique in a single neuron of cultured cerebellar granule cells.