RESUMEN
Light is a crucial environmental signal and photosynthetic energy for plant growth, development, and primary and secondary metabolism. To explore the effects of light quality on the growth and root exudates of hydroponic lettuce (Lactuca sativa L.), white LED (W, control) and four the mixtures of red (R) and blue (B) LED with different R/B light intensity ratios (R/B = 2, 2R1B; R/B = 3, 3R1B; R/B = 4, 4R1B; and R/B = 8, 8R1B) were designed. The results showed that the biomass of lettuce under 8R1B and W treatments was higher than that under other light quality treatments. The photosynthetic rate (Pn) under red and blue light was significantly higher than that of white light. Total root length, root surface area, and root volume were the highest under 8R1B. 4R1B treatment significant increased root activity by 68.6% compared with W. In addition, total organic carbon (TOC) content, TOC content/shoot dry weight, TOC content/root dry weight, and TOC content/root surface area were the highest under 4R1B. Moreover, 8R1B treatment reduced the concentration of benzoic acid and salicylic acid, and the secretion ability of benzoic acid and salicylic acid by per unit root surface area and accumulation by per unit shoot dry weight. In addition, 2R1B and 3R1B reduced the secretion ability of gallic acid and tannic acid by per unit root surface area and accumulation by per unit shoot dry weight. In conclusion, this study showed that the secretion of autotoxins could be reduced through the mediation of red and blue light composition of LEDs in a plant factory. In terms of autotoxin secretion reduction efficiency and yield performance of lettuce, 8R1B light regime is recommended for practical use.
RESUMEN
Epimedium, a traditional Chinese herb, has been used for the remedy of coronary heart disease, impotence and osteoporosis in traditional oriental medicine. However, despite extensive pharmacological studies, the molecular mechanism of the anti-heart failure effect of epimedium is little known. In the present study, we investigated the pharmacological action mechanism of ethanol extract of epimedium (EPI-ext) on isoproterenol-induced congestive heart failure (CHF) in rats. Isoproterenol administration resulted in severe heart failure, as shown by the increased levels of left ventricular (LV) weight index and heart rate, as well as LV end diastolic pressure, and by the decreased levels of LV systolic pressure, maximal rate of LV pressure rise, and maximal rate of LV pressure decline. EPI-ext dose-dependently reversed the changes of these cardiac morphometric and hemodynamic parameters. In addition, EPI-ext significantly inhibited the serum levels of tumor necrosis factor alpha, norepinephrine, angiotensin II and brain natriuretic peptide in rats with CHF and improved the histological changes including cadiocyte hypertrophy, cadiocyte degeneration, inflammatory infiltration, and cardiac desmoplasia. Furthermore, the expression and activities of matrix metalloproteinase-2 and -9, which regulate collagen production, were also blocked by EPI-ext. Moreover, myocardial apoptosis was remarkably attenuated by EPI-ext through the regulating Bcl-2/Bax axle. In conclusion, EPI-ext ameliorates LV dysfunction and cardiac remodeling through down-regulating matrix metalloproteinase-2 and -9 activity and myocardial apoptosis in rats with CHF.