Seed priming with calcium chloride enhances stress tolerance in rice seedlings.

Calcium is a crucial second messenger in plant cells and contributes to plant resistance against biotic and abiotic stress. Plant defense priming with natural or synthetic compounds leads to quicker and stronger resistance responses. However, whether pretreatment of plant seeds with calcium could improve their resistance to stress remains poorly understood. In this study, we showed that rice seedlings grown from calcium chloride (CaCl2)-pretreated seeds displayed enhanced resistance to the rice blast fungus Magnaporthe oryzae and the rice bacterial pathogen Xanthomonas oryzae pv. Oryzae (Xoo). Seed priming with CaCl2 also led to enhanced rice tolerance to salt and cold. Furthermore, the reactive oxygen species (ROS) burst increased significantly upon immunity activation in the leaves of rice seedlings grown from CaCl2-pretreated seeds. Additionally, we analyzed the rice calmodulin-binding protein 60 (OsCBP60) family and found that there were 19 OsCBP60s in rice cultivar Zhonghua 11 (ZH11). The transcripts of several OsCBP60s were chitin- and M. oryzae-inducible, suggesting that they may contribute to rice resistance. Taken together, these data indicate that seed priming with CaCl2 can effectively enhance rice tolerance to multiple stresses, perhaps by boosting the burst of ROS, and OsCBP60 family members may also play an essential role in this process.

FGF-21 Elevated IL-10 Production to Correct LPS-Induced Inflammation.

Fibroblast growth factor 21 (FGF-21) has been previously judged as a major metabolic regulator. In this paper, we show that FGF-21 has a potential role in anti-inflammation and immunoregulation. In vivo, treatment with exogenous FGF-21 can alleviate LPS-induced inflammation. In vitro, FGF-21 inhibited LPS-induced IL-1ß expression in THP-1 cells. Furthermore, besides the NF-κB pathway, the mechanism of action of FGF-21 was observed to involve the elevation of IL-10 in the ERK1/2 pathway. This study clearly indicates that FGF21 can be used as an attractive target for the management of inflammatory disorders. This piece of research indicates that FGF-21 could have much value in the management of inflammatory disorders.

FGF-21 Plays a Crucial Role in the Glucose Uptake of Activated Monocytes.

Monocytes display a gradual change in metabolism during inflammation. When activated, the increase in glucose utilization is important for monocytes to participate in immune and inflammatory responses. Further studies on the mechanism underlying this biological phenomenon may provide a new understanding of the relationship between immune response and metabolism. The THP-1 cells were used as a monocyte model. The cells were activated with lipopolysaccharide (LPS). Glucose uptake was measured using flow cytometry. The expression of fibroblast growth factor 21 (FGF-21), glucose transporter 1 (GLUT-1), and other FGF-21 signaling pathway-related factor mRNAs was determined by real-time polymerase chain reaction. Further, the relationship between FGF-21 expression in monocytes and phosphatidylinositol-3-kinase (PI3K)-protein kinase B (Akt) signaling pathway was determined by Western blotting. LPS elevated FGF-21 expression in monocytic THP-1 cells in vitro. Functional assays showed that the phenomenon in which LPS and FGF-21 stimulated glucose uptake in monocytic THP-1 cells could be inhibited by FGFR inhibitor. The mechanism of elevation of FGF-21 was found to involve the PI3K/Akt signaling pathway. This study indicated that FGF-21 could regulate the immune response indirectly by influencing the glucose uptake of activated monocytes cells.