ARE THE GENES CA6, TAS2R38, TCF7L2, FTO, TAS1R2, TAS1R3, GNAT3 RECEPTOR POLYMORPHISMS INVOLVED ON EXCEPTIONAL LONGEVITY AND RISK OF SARCOPENIA? A CROSS SECTIONAL STUDY IN ITALIAN AGING POPULATION
GENETIKA-BELGRADE
Authors: Perna, Simone
Abstract
This study hypothesized that genetic polymorphisms of different genes could modulate the lifespan and muscle health or sarcopenia. We investigated the possible associations between longevity and the common genetic variation polymorphism such as rs713598, rs7903146, rs9939609, rs35874116, rs2274333, rs7792845, rs35744813 in a population of 360 Italian elderly aged 65-100 years. The polymorphism rs9939609, of the FTO gene, shows an association (p<0.001) with longevity. In particular, the frequency of T/T homozygotes increases gradually from 35% in subjects aged 65-80 ys up to 80% in centenarians. The polymorphism of rs2274333 (CA6) gene shows that A/G frequency increases continuously through older classes reaching the 80% in (95-100) (p trend <0.05). Another important founding regards the polymorphism of rs35744813 of TAS1R3 gene. The C/C genotype frequency is over 80% in all classes (65-95 years) but appears increase in oldest old and reach 100% (95-100 ys). While T allele frequency decrease continuously through older classes reaching the 0% in T/T and 5% in C/T in (95-100) (p-trend <0.05). These data provide suggestive evidence on the possible correlation between longevity and FTO gene (obesity related), CA6 gene (the gustinbitter taste related) and TAS1R3 (umami taste stimulus related). None associations with sarcopenia were detected.
Morphology of GNAT3-immunoreactive chemosensory cells in the rat larynx
JOURNAL OF ANATOMY
Authors: Masuda, Haruka; Nakamuta, Nobuaki; Yamamoto, Yoshio
Abstract
The upper airways play important roles in respiratory defensive reflexes. Although solitary chemosensory cells and chemosensory cell clusters have been reported in the laryngeal mucosa of mammalian species, the distribution and cellular morphology of chemosensory cells remain unclear. In the present study, the distribution and morphology of solitary chemosensory cells and chemosensory cell clusters were examined by immunofluorescence for GNAT3 on whole-mount preparations of the rat laryngeal mucosa. Electrophysiological experiments were performed to analyze the respiratory reflexes evoked by bitter stimuli to the laryngeal cavity. In the whole area of the laryngeal mucosa, the numbers of GNAT3-immunoreactive solitary chemosensory cells and chemosensory clusters were 421.0 +/- 20.3 and 62.7 +/- 6.9, respectively. GNAT3-immunoreactive solitary chemosensory cells were mainly distributed in the mucosa overlying epiglottic and arytenoid cartilage, and chemosensory clusters were mainly distributed on the edge of the epiglottis and aryepiglottic fold. GNAT3-immunoreactive solitary chemosensory cells were slender with elongated processes or had a flask-like/columnar shape. The number of GNAT3-immunoreactive cells in chemosensory clusters was 6.1 +/- 0.4, ranging between 2 and 14 cells. GNAT3-immunoreactive cells in the cluster were variform and the tips of apical processes gathered at one point at the surface of the epithelium. The tips of apical cytoplasmic processes in solitary chemosensory cells and cells in the cluster were immunoreactive for espin, and faced the laryngeal cavity. Physiological experiments showed that the application of 10 mm quinine hydrochloride to the laryngeal cavity decreased respiratory frequency. The present results revealed the chemosensory field of the larynx and the morphological characteristics of the laryngeal chemosensory system for respiratory depression.