Lentinan Inhibited the Activation of Th2 Cells in Allergic Mice by Reducing the Amplitude of Changes in Biological Rhythm.

INTRODUCTION: Biological rhythm is inextricably linked to the physiological mechanisms of allergic diseases, but the exact mechanisms are still poorly understood. Clinical studies have reported rhythmic fluctuations in allergic diseases. The search for natural and harmless active ingredients based on biological rhythm with which to regulate allergic diseases is essential for the control of food allergy. METHODS: In this study, mice were treated at different time points to determine the link between the severity of allergic reactions and the circadian clock genes. The mice were treated with lentinan, either continuously or discontinuously, to assess their clinical symptoms, vascular permeability, immune cells, cytokines, and clock genes. Specifically, rat basophilic leukemia (RBL-2H3) cells were treated with lentinan and the rhythmic changes of cell degranulation were measured. RESULTS: The results in different models showed that the allergic reactions in mice treated at different time points were significantly different and thus related to fluctuations in biological rhythm. Treatment with lentinan was found to reduce the amplitude of changes in the clock genes, such as the activation of Per and Cry proteins in allergic mice, as well as to regulate biological rhythm in cells, inhibit the activation of Th2 cells, and alleviate allergic reactions. Furthermore, lentinan changed the rhythm of degranulation in RBL-2H3 cells. CONCLUSION: Lentinan was, therefore, determined to successfully alleviate allergic reactions by reducing the amplitude of changes in the body's biological rhythm, inhibiting the activation of Th2 cells, and affecting the immune microenvironment.

Effect of Pennisetum giganteum z.x.lin mixed nitrogen-fixing bacterial fertilizer on the growth, quality, soil fertility and bacterial community of pakchoi (Brassica chinensis L.).

Biofertilizer plays a significant role in crop cultivation that had reduced its inorganic fertilizer use. The effects of inorganic fertilizer reduction combined with Pennisetum giganteum z.x.lin mixed nitrogen-fixing biofertilizer on the growth, quality, soil nutrients and diversity of the soil bacterial community in the rhizosphere soil of pakchoi were studied. The experiment composed of 6 treatments, including CK (no fertilization), DL (10% inorganic fertilizer reduction combined with Pennisetum giganteum z.x.lin mixed nitrogen-fixing biofertilizer), ZL (25% inorganic fertilizer reduction combined with Pennisetum giganteum z.x.lin mixed nitrogen-fixing biofertilizer), SL (50% inorganic fertilizer reduction combined with Pennisetum giganteum z.x.lin mixed nitrogen-fixing biofertilizer), FHF (100% inorganic fertilizer) and JZ (100% inorganic fertilizer combined with sterilized Pennisetum giganteum z.x.lin mixed nitrogen-fixing biofertilizer). Compared with conventional fertilization, the 25% reduction in chemical fertilizer applied with the Pennisetum giganteum mixed nitrogen-fixing biofertilizer resulted in higher plant height, plant weight, chlorophyll content, soluble protein content, soluble sugar content, vitamin C content, alkali hydrolyzed nitrogen content, available phosphorus content, available potassium content and organic matter content in pakchoi, and these variables increased by 11.81%, 8.54%, 7.37%, 16.88%, 17.05%, 23.70%, 24.24%, 36.56%, 21.09% and 19.72%, respectively. In addition, the 25% reduction in chemical fertilizer applied with the Pennisetum giganteum mixed nitrogen-fixing biofertilizer also had the lowest nitrate content, which was 53.86% lower than that with conventional fertilization. Different fertilizer treatments had a significant effect on the soil bacterial community structure. Compared with conventional fertilization, the coapplication of Pennisetum giganteum z.x.lin mixed nitrogen-fixing biofertilizer and inorganic fertilizer significantly increased the relative abundance of Proteobacteria and Actinobacteria in the soil. The results of the redundancy analysis (RDA) showed that soil organic matter, alkali-hydrolyzed nitrogen, available phosphorus, available potassium, pH and water content had a specific impact on the soil bacterial community. Among the factors, soil water content was the main factor affecting the soil bacterial community, followed by soil organic matter, soil pH, available potassium, soil available phosphorus and soil alkali-hydrolyzed nitrogen.