No abstract

In order to obtain greater insights into the molecular mechanisms accompanying hormonal aging the effects of growth hormone (GH), insulin-like growth factor-I (IGF-I), 17beta-estradiol, progesterone and dehydroepiandrosterone were tested as single agents in concentrations corresponding to 20- and 60-year-old females on human SZ95 sebocytes and fibroblasts. Cell proliferation and viability were measured by 4-methylumbelliferyl heptanoate and lactate dehydrogenase microassays, respectively, whereas lipid accumulation was documented via nile red microassay and fluorescence microscopy. mRNA and protein expression were evaluated via real-time RT-PCR and Western blotting or ELISA, accordingly. Our results depict the importance of IGF-I for lipid synthesis in SZ95 sebocyte and demonstrate the lack of 17beta-estradiol, dehydroepiandrosterone and progesterone activity on lipid synthesis and SZ95 sebocyte proliferation suggesting that the action of these hormones in vivo may be implemented through indirect pathways. Fibroblast showed to be more susceptible to 17beta-estradiol treatment, while IGF-I could significantly stimulate fibroblast proliferation in a dose-dependent manner. Furthermore, an interplay between the 17beta-estradiol and IGF-I signaling pathway was documented in both cell types. In conclusion, IGF-I is a key regulator of human skin aging and declining IGF-I levels with age may play a significant role in the reduction of skin surface lipids and thickness.

No abstract

The feasibility of disrupting sexual communication in oriental beetle, Exomala orientalis (Waterhouse) with a microencapsulated sprayable formulation of (Z)-and (E)-7-tetradecen-2-one, the major and minor pheromone components, respectively, was evaluated in blueberries and ornamental nurseries during 1998 and 1999 seasons in southern New Jersey. In 1998, pheromone-baited traps captured signiÞcantly fewer male beetles in blueberries, treated with a 9:1 blend of (Z)-and (E)-7-tetradecen-2-one at 100 g (AI)/ha of the major component, or in nurseries treated with (Z)-7-tetradecen-2-one alone at the same rate, compared with trap captures in untreated control plots. The percentage of reduction in trap captures (disruption index) in plots treated with the blend in blueberries was comparable to reductions in trap captures in nurseries (97 versus 92%) treated with the major component alone. During 1999, pheromone trap captures in blueberry and nursery plots treated with a 93:7 blend of (Z)-and (E)-7-tetradecen-2-one at 37.5 g (AI)/ha of the major component were on an average 92 and 82% lower compared with trap captures in untreated control plots, respectively. SigniÞcantly fewer tethered virgin female oriental beetles were found in copula/contact with males in treated blueberry Þelds relative to those deployed in untreated control plots. These results suggest that communication disruption is a promising strategy to manage oriental beetle populations in blueberries and ornamental nurseries. This is the Þrst study to document the feasibility of disrupting sexual communication in a soil-dwelling coleopteran with applications of sex pheromone components to the soil.