Distribution of copper in soil and rice system of Hainan Island, China

ABSTRACT This research aimed to discover the distribution and the primary influence factors of Cu in the soil-rice systems of tropical farmland. Soil samples of farmland and rice plant (stalk and polished rice) from the western region of Hainan Island were collected and studied. The results showed that the average Cu content in the topsoil of the study area was 15.75 mg kg-1; the highest Cu content (45.92 mg kg-1) was found in the rice fields of the northern area, where pyroclastic parent material is distributed. Thus, there is a potential for Cu contamination of the rice grown in this region. The average contents of Cu in the rice stalks and polished rice were 16.9 and 5.68 mg kg-1, respectively, indicating that the stalks had a larger capacity for Cu bioaccumulation than the polished rice. The bioaccumulation factor (BAF) of Cu in rice was found to decrease with increased Cu contents in the soil. In regards to the northern farmlands with high Cu contents in the soil derived from pyroclastic deposits, an alkaline fertilizer should be used to prevent the risk of Cu pollution in the polished rice, as soil acidification can promote the uptake and accumulation of Cu to some extent

Salvianolic acid B protects against lipopolysaccharide-induced behavioral deficits and neuroinflammatory response: involvement of autophagy and NLRP3 inflammasome

Abstract Background The NLRP3 inflammasome activation and neuroinflammation are known to be involved in the pathology of depression, whereas autophagy has multiple effects on immunity, which is partly mediated by the regulation of inflammasome and clearance of proinflammatory cytokines. Given the emerging evidence that autophagy dysfunction plays an essential role in depression, it is very likely that autophagy may interact with the inflammatory process in the development and treatment of depression. Salvianolic acid B (SalB), a naturally occurring compound extracted from Salvia miltiorrhiza, contains anti-inflammatory and antidepression properties and has recently been proven to modulate autophagy. In this study, we sought to investigate whether autophagy is involved in the inflammation-induced depression and the antidepressant effects of SalB. Methods The effects of prolonged lipopolysaccharide (LPS) treatment and SalB administration on behavioral changes, neuroinflammation, autophagic markers and NLRP3 activation in rat hippocampus were determined by using behavioral tests, real-time PCR analysis, western blot, and immunostaining. Results Our data showed that periphery immune challenge by LPS for 2 weeks successfully induced the rats to a depression-like state, accompanied with enhanced expression of pro-inflammatory cytokines and NLRP3 inflammasome activation. Interestingly, autophagic markers, including Beclin-1, and the ratio of LC3II to LC3I were suppressed following prolonged LPS exposure. Meanwhile, co-treatment with SalB showed robust antidepressant effects and ameliorated the LPS-induced neuroinflammation. Additionally, SalB restored the compromised autophagy and overactivated NLRP3 inflammasome in LPS-treated rats. Conclusions Collectively, these data suggest that autophagy may interact with NLRP3 activation to contribute to the development of depression, whereas SalB can promote autophagy and induce the clearance of NLRP3, thereby resulting in neuroprotective and antidepressant actions