Energy balance is monitored by the hypothalamus, which responds to peripheral signals by releasing neuropeptides that regulate energy intake and expenditure. In this study, we constructed pro-opiomelanocortin (POMC) and "cocaine and amphetamine-related transcript" (CART) promoter-driven luciferase plasmids and transformed them permanently into both N29-2 neuronal cells and human SHSY5Y cells. Using reporter gene assays, we identified apigenin from the seeds of Perilla frutescens Britton var crispa (Benth.) using activity-guided fractionation. The 50% promoting concentrations (EC₅₀) of apigenin on POMC and CART were 0.93 μM and 0.67 μM, respectively, in N29-2 cells, without significant cytotoxic effects. Shortterm food intake was decreased in C57BL/6J mice after an intraperitoneal injection of apigenin (10 mg/kg; p < 0.05). Food intake and body weight gain for 30 days were also reduced slightly in mice fed a high-fat diet containing apigenin (0.05%, w/w; p < 0.05). These results indicate that apigenin increased POMC and CART gene expression in neuronal cells and significantly reduced food intake in C57BL/6 mice, which may be related to the anorexigenic neuropeptides POMC and CART.
Extreme climate events such as heat waves, drought, and heavy rainfall are occurring more frequently and are more intense due to ongoing climate change. This study evaluated the early growth performance of one-year-old Larix kaempferi (Lamb.) Carr. seedlings under open-field extreme climate conditions including experimental warming and different precipitation regimes. We recorded the survival rate, root collar diameter, height, biomass, shoot-to-root ratio, and seedling quality index using nine treatments (three temperature levels, i.e., control, warming by 3 °C and by 6 °C, × three precipitation levels, i.e., control, drought, and heavy rainfall) in July and August 2020. The survival rate of seedlings did not differ between treatments, showing high values exceeding 94% across treatments. The measured shoot height was largest under warming by 3 °C and high rainfall, indicating that moderate warming increased seedling height growth in a moist environment. Heavy rainfall decreased stem volume by 21% and 25% under control and warming by 6 °C treatments, respectively. However, drought manipulation using rain-out shelters did not decrease the growth performance. Overall, extreme climate events did not affect the survival rate, biomass, shoot-to-root ratio, and seedling quality index of L. kaempferi. We thus conclude that, regarding growth responses, L. kaempferi seedlings may be resistant to short-term extreme warming and drought events during summer.
<p>Extreme climate events, generally defined as inordinately hotter, drier, or wetter compared to the historical period, are showing an increasing trend in terms of their frequency, intensity, and magnitude. They can impair the recovery system of plants, and thus, there is a need to understand their effects on plants. Here, we constructed a temperature and precipitation manipulation system to simulate extreme climate events for plants in the open field in April, 2020. We applied a factorial combination of three temperature levels (control, +3 &#176;C, and +6 &#176;C) and three precipitation levels (control, drought, and heavy rainfall) with six replicates (i.e., 54 plots of 1.5 m &#215; 1.0 m) from April to June, 2020. Infrared heaters were adopted for simulating extreme heat since they are able to provide a realistic heating mechanism. The targeted temperature was automatically maintained by the data loggers and relays. For the extreme drought simulation, automatic rainout shelters intercepted ambient rainfall, closing only when detecting rainfall to avoid a disturbance of light absorption and passive warming. The rainfall simulator sprayed water from a height of 1.6 m above the ground using spraying nozzles and, the spraying time and pressure were set by the hooked-up pump and control panel to generate realistic rainfall. An infrared thermometer and a soil moisture and temperature sensor per plot measured the soil surface temperature and soil water content, respectively. As a result, the infrared heaters increased the mean soil surface temperature (&#176;C &#177; standard error) by 2.7 &#177; 0.2 and 5.7 &#177; 0.5 in the +3 &#176;C and +6 &#176;C plots, respectively, compared to that in the control. The rainout shelter and rainfall simulator successfully produced extreme drought and heavy rainfall conditions, showing higher mean soil water contents (vol. %) of 4.44 &#177; 0.01 in the drought plots and 8.45 &#177; 0.03 in the heavy rainfall plots than that in the control (7.19 &#177; 0.03). Our multifactor manipulation system can provide a mechanistic understanding of the combined extreme stresses on soils and plants (e.g., soil microbial activity, seed germination, and growth of seedlings) through the comparison between the impact of single and multiple factors. Furthermore, the system has the advantage of applying diverse intensities of extreme climate events without restrictions on regions and scenarios by altering the settings of data loggers or the control panel. The system in this study can aid in investigating and modeling the mechanisms between extreme climate events, and soils and plants.</p> <p>Acknowledgment: This study was carried out with the support of the National Research Foundation, Republic of Korea (Project No. 2022R1A2C1011309) and Korea Forest Service (Project No. 2020181A00-2222-BB01).</p>
<p>Mangrove associates, generally distributed in the landward fringe of mangrove forests, are one of the major carbon sinks. Mangrove associates are expected to increase in South Korea as their spatial distribution is shifting to poleward with global warming. However, understanding of carbon stocks and fluxes of mangrove associates is still limited. In this study, we estimated carbon stocks in soils and forest floors and measured carbon fluxes of soil CO<sub>2</sub> efflux and net photosynthesis of <em>Hibiscus hamabo</em> and <em>Paliurus ramosissimus</em>, mangrove associates which inhabit naturally in Jeju Island, South Korea from April to October, 2022. Four sites of <em>H. hamabo </em>(Gimnyeong &#8211; coast, Hado, Seongsan and Wimi) and <em>P. ramosissimus </em>(Gimnyeong &#8211; wetland and Daejeong 1 ~ 3) were selected. Soil carbon stocks at 0 &#8211; 10 cm depth from Gimnyeong &#8211; wetland, Seongsan, and Hado where soil horizons developed, and forest floor carbon stocks were quantified. In addition, soil CO<sub>2</sub> efflux and net photosynthesis were measured once a month. Mean soil carbon stocks (t C ha<sup>-1</sup>) ranged from 29.0 to 30.1 while mean forest floor carbon stocks (t C ha<sup>-1</sup>) ranged from 2.8 to 5.8. Soil CO<sub>2</sub> efflux rate (&#181;mol CO<sub>2</sub> m&#8315;&#178; s&#8315;&#185;) in August was significantly higher than that in April and October. There was a positive correlation between soil CO<sub>2</sub> efflux and soil (p < 0.001, r = 0.41) and air (p < 0.001, r = 0.52) temperatures compared to other factors such as soil water content (p > 0.05), and electrical conductivity (p > 0.05). Net photosynthesis (&#181;mol m&#8315;&#178; s&#8315;&#185;) was significantly high in July, and there were no significant differences among sites. Soil carbon stocks of the two species were higher than those of <em>Quercus mongolica</em> forests (27.8) in South Korea. Moreover, forest floor carbon stocks were higher compared to those of <em>Q. glauca</em> forests (1.32) in Jeju Island. Mean net photosynthesis (mean &#177; standard error, &#181;mol m&#8315;&#178; s&#8315;&#185;) of <em>H. hamabo</em> (8.9 &#177; 0.9) and <em>P. ramosissimus </em>(8.8 &#177; 1.3)<em> </em>in July were higher than that of <em>Eleutherococcus gracilistylus</em> (6.74 &#177; 0.26), a deciduous shrub inhabiting in Jeju Island. This study provides the first data base to estimate carbon stocks and fluxes of mangrove associates in South Korea and the results showed that <em>H. hamabo </em>and <em>P. ramosissimus</em> seem to be promising species for carbon sinks.</p> <p><strong>Acknowledgement</strong></p> <p>This study was carried out with the support of the National Research Foundation, Republic of Korea (Project No. 2022R1A2C1011309), and the Warm-temperate and Subtropical Forest Research Center (Project No. FE100-2022-04-2022).</p>
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.