The plant root is an important storage organ that stores indole-3-acetic acid (IAA) from the apical meristem, as well as nitrogen, which is obtained from the external environment. IAA and nitrogen act as signaling molecules that promote root growth to obtain further resources. Fluctuations in the distribution of nitrogen in the soil environment induce plants to develop a set of strategies that effectively improve nitrogen use efficiency. Auxin integrates the information regarding the nitrate status inside and outside the plant body to reasonably distribute resources and sustainably construct the plant root system. In this review, we focus on the main factors involved in the process of nitrate- and auxin-mediated regulation of root structure to better understand how the root system integrates the internal and external information and how this information is utilized to modify the root system architecture.

According to Traditional Chinese Medicine (TCM), Aconiti Radix Cocta (AC) is clinically employed to expel wind, remove dampness, and relieve pain. We evaluated the antirheumatoid arthritis (RA) activities and underlying mechanisms of AC. The chemical constituents of AC were analyzed by high-performance liquid chromatography (HPLC) using three reference compounds (benzoylaconitine, benzoylmesaconine, and benzoylhypacoitine). The anti-RA effects of AC were evaluated in adjuvant-induced arthritis (AIA) rats by hind paw volume and histopathological analysis. The effects of AC on inflammatory cytokines (IL-1β and IL-17A) were determined by enzyme-linked immunosorbent assay. The regulation of cyclooxygenases (COX-1 and/or COX-2) was determined by Western blot and real-time quantitative reverse transcription polymerase chain reaction analyses. AC significantly reduced paw swelling, attenuated the inflammation and bone destruction in joint tissues, and reduced IL-1β and IL-17A in the serum. Moreover, AC downregulated the expression of COX-1 and COX-2 in the synovial tissues. We also identified that AC possesses significant anti-RA activities on AIA, which may be ascribed to the regulation of inflammatory cytokines IL-1β and IL-17, as well as to the inhibition of arachidonic acid signaling pathways. Our findings provide theoretical support for AC as an effective nature-derived therapeutic agent for RA treatment.