Carlo Zancanaro

α‐Gustducin expression in the vomeronasal organ of the mouse

The expression of α‐gustducin, a G protein α subunit involved in bitter and sweet taste transduction, was investigated in chemosensory tissues of adult mice. By immunohistochemistry, α gustducin was absent in the olfactory neuroepithelium. Instead, α gustducin was expressed in a subset of bipolar cells in the proliferative zone of the vomeronasal neuroepithelium as well as in taste buds. Northern blot analysis confirmed the presence of α gustducin in isolated vomeronasal organs. Moreover, immunohisto‐ chemistry revealed the expression of α gustducin in scattered cells of the nasal respiratory epithelium. These results show for the first time that α gustducin is expressed in chemosensory tissue outside the alimentary tract, suggesting that common transduction mechanisms could be shared by apparently unrelated chemosensory tissues.

The calcium channel blocker lacidipine reduces the development of atherosclerotic lesions in the apoE-deficient mouse.

Background Lacidipine is a widely used calcium-channel blocker, which has both long-lasting antihypertensive activity and also antioxidant properties. Previous studies have demonstrated the ability of lacidipine to reduce the development of atherosclerotic lesions in several animal models. Objective The present study investigated the anti-atherosclerotic potential of lacidipine in the apoE-deficient mouse, an experimental model of atherosclerosis showing progressively complex and widespread lesions which closely resemble the inflammatory-fibrous plaques seen in humans. Methods Lacidipine was administered daily by gavage for 10 weeks at dose levels of 0 (control), 0.3, 1.0 and 3.0 mg/kg. Results Lacidipine administration reduces the extension of atherosclerotic lesions in the aorta of the apoE-deficient mouse without affecting plasma lipid levels. We also show that apoE-deficient mice have four-fold higher values of the proatherogenic peptide, endothelin, compared with the wild-type C57BL/6 mouse and that lacidipine administration reduced, in a dose-dependent manner, the concentrations of plasma endothelin. Conclusion Lacidipine has anti-atherogenic effects in the apoE-deficient mouse, and reduces plasma endothelin concentrations.

Immunohistochemical evidence suggests intrinsic regulatory activity of human eccrine sweat glands.

Immunohistochemistry of normal eccrine sweat glands was performed on paraffin sections of human skin. Immunoreactivity (ir) for neuron specific enolase, S100 protein (S100), regulatory peptides, nitric oxide synthase type I (NOS‐I) and choline‐acetyltransferase (ChAT) was found in small nerve bundles close to sweat glands. In the glands, secretory cells were labelled with anticytokeratin antibody. Using antibodies to S100, calcitonin gene‐related peptide (CGRP) and substance P (SP) a specific distribution pattern was found in secretory cells. Granulated (dark) and parietal (clear) cells were immunopositive for CGRP, and S100 and SP, respectively. Immunoreactivity was diffuse in the cytoplasm for CGRP and S100, and peripheral for SP. Myoepithelial cells were not labelled. Electron microscopy revealed electron dense granules, probably containing peptide, in granulated cells. Using antibodies to NOS‐I and ChAT, ir was exclusively found in myoepithelial cells. Immunoreactivity for the atrial natriuretic peptide was absent in sweat glands. These results provide evidence for the presence of both regulatory peptides involved in vasodilation and key enzymes for the synthesis of nitric oxide and acetylcholine in the secretory coil of human sweat glands. It is suggested that human sweat glands are capable of some intrinsic regulation in addition to that carried out by their nerve supply.

Immunoelectron microscopical identification of the uncoupling protein in brown adipose tissue mitochondria

The distribution of the uncoupling protein (UCP) in brown adipocyte mitochondria of the hibernant Muscardinus avellanarius was obtained by ultrastructural immunocytochemistry. In both cryosections and sections of Lowicryl‐embedded material UCP was localized in the mitochondrial cristae of brown adipocytes, but not in liver mitochondria. It should now be possible to easily identify the morphology of cells committed to BAT differentiation in the tissue as well as in cell culture.

Nuclei of aged myofibres undergo structural and functional changes suggesting impairment in RNA processing.

Advancing adult age is associated with a progressive decrease in skeletal muscle mass, strength and quality known as sarcopenia. The mechanisms underlying age-related skeletal muscle wasting and weakness are manifold and still remain to be fully elucidated. Despite the increasing evidence that the progress of muscle diseases leading to muscle atrophy/dystrophy may be related to defective RNA processing, no data on the morpho-functional features of skeletal muscle nuclei in sarcopenia are available at present. In this view, we have investigated, by combining morphometry and immunocytochemistry at light and electron microscopy, the fine structure of myonuclei as well as the distribution and amount of RNA processing factors in skeletal myofibres of biceps brachii and quadriceps femoris from adult and old rats. Results demonstrate that the myonuclei of aged type II fibres show an increased amount of condensed chromatin and lower amounts of phosphorylated polymerase II and DNA/RNA hybrid molecules, clearly indicating a decrease in pre-mRNA transcription rate compared to adult animals. In addition, myonuclei of aged fibres show decreased amounts of nucleoplasmic splicing factors and an accumulation of cleavage factors, polyadenilated RNA and perichromatin granules, suggesting a reduction in the processing and transport rate of pre-mRNA. During ageing, it seems therefore that in rat myonuclei the entire production chain of mRNA, from synthesis to cytoplasmic export, is less efficient. This failure likely contributes to the reduced responsiveness of muscle cells to anabolic stimuli in the elderly.

Nuclear bodies are usual constituents in tissues of hibernating dormice

In previous studies we demonstrated in several tissues of the hazel dormouse Muscardinus avellanarius that during hibernation cell nuclei contain particular structural constituents absent in euthermia. In the present study we examine the same tissues in euthermic and hibernating individuals of the edible dormouse Glis glis in order to investigate possible modifications of nuclear structural constituents occurring during hibernation in this species.

Anthropometry and body composition of female handball players according to competitive level or the playing position

Abstract Anthropometry and body composition were investigated in 43 female handball players from the Italian championships, grouped according to their competitive level (elite vs. sub-elite) or their playing position [goalkeeper (n = 7), back (n = 14), wing (n = 18), or pivot (n = 4)]. The anthropometry consisted of several circumferences, lengths, widths, and skinfold measurement at six sites; the regional and total body compositions were assessed by means of dual-energy X-ray absorptiometry (DXA). One-way ANOVA was used for statistical analysis, with a Bonferroni post-hoc test where needed. The results showed that elite players have significantly lower percentages of fat and higher bone mineral content than sub-elite as well as a clear tendency to accrue more lean mass, especially in upper limbs. Overall, the physical characteristics and body composition of handball players in Italy compared unfavourably with those in other countries, suggesting a need for improved selection and training. When playing position was included in the analysis of the whole group of handball players (n = 43) significant differences were found between the stature, mass, body mass index (BMI), several skinfolds, circumferences and lengths, and total body mineral mass, lean mass and fat mass of players in different positions. Post-hoc analysis suggests that players on the wing and in goalkeeper positions differed most from one another. These findings confirm and expand on previous data about the presence of anthropometric differences within playing positions in handball.

FINE STRUCTURAL MODIFICATIONS OF LIVER, PANCREAS AND BROWN ADIPOSE TISSUE MITOCHONDRIA FROM HIBERNATING, AROUSING AND EUTHERMIC DORMICE

An ultrastructural and morphometric study was performed on mitochondria of euthermic, hibernating and arousing hazel dormice (Muscardinus avellanarius), in order to investigate possible modifications during the seasonal cycle. Hepatocytes, pancreatic acinar cells and brown adipocytes were considered. Our results demonstrated that: (1) the general morphology of mitochondria of all cell types shows slight modifications during the seasonal cycle; (2) mitochondrial size and inner membrane length significantly increase from euthermia to hibernation and decrease upon arousal in all cell types; (3) mitochondrial matrix granules drastically increase in number during hibernation and decrease upon arousal in hepatocytes and pancreatic acinar cells, whereas they do not change in brown adipocytes. These structural modifications are probably related to the changes in cellular energy needs during the euthermia—hibernation—arousal cycle.

Ten-week Whole-body Vibration Training Improves Body Composition and Muscle Strength in Obese Women

This work explored the short-term effect of whole body vibration (WBV) training on anthropometry, body composition and muscular strength in obese women. Fifty obese women (age=46.8±7.81[SD]y; BMI=35.1±3.55kg/m2) were assigned to a ten-week WBV training period, two times a week (in each session, 14min vibration training, 5min rest; vibration amplitude 2.0-5.0mm, frequency 40-60Hz), with (n=18) or without (n=17) radiofrequency, or to a non-exercise control group (n=15). Subjects were instructed not to change their habitual lifestyle. Before and after the ten-week experimental period, anthropometric measurements, dual-energy X-ray absorptiometry (DXA), and the leg press, leg curl and leg extension strength tests were carried out. All changes in the two groups of WBV training, with or without radiofrequency, were similar and these groups were combined in a single WBV intervention group. As compared to controls, subjects submitted to WBV training had significantly lower BMI, total body and trunk fat, sum of skinfolds and body circumferences. On the other hand, lower limb strength tests were increased in the WBV group. These preliminary results suggest that WBV training may improve body composition and muscular strength in obese women and may be a useful adjuvant to lifestyle prescriptions.

Pre-mRNA Processing Is Partially Impaired in Satellite Cell Nuclei from Aged Muscles

Satellite cells are responsible for the capacity of mature mammalian skeletal muscles to repair and maintain mass. During aging, skeletal muscle mass as well as the muscle strength and endurance progressively decrease, leading to a condition termed sarcopenia. The causes of sarcopenia are manifold and remain to be completely elucidated. One of them could be the remarkable decline in the efficiency of muscle regeneration; this has been associated with decreasing amounts of satellite cells, but also to alterations in their activation, proliferation, and/or differentiation. In this study, we investigated the satellite cell nuclei of biceps and quadriceps muscles from adult and old rats; morphometry and immunocytochemistry at light and electron microscopy have been combined to assess the organization of the nuclear RNP structural constituents involved in different steps of mRNA formation. We demonstrated that in satellite cells the RNA pathways undergo alterations during aging, possibly hampering their responsiveness to muscle damage.