Anti-Inflammatory Effects and Mechanisms of Dandelion in RAW264.7 Macrophages and Zebrafish Larvae.

Dandelions (Taraxacum spp.) play an important role in the treatment of inflammatory diseases. In this study, we investigated the anti-inflammatory effects of Dandelion Extract (DE) in LPS-induced RAW264.7 macrophages and copper sulfate (CuSO4)-induced zebrafish larvae. DE was not toxic to RAW264.7 cells at 75 µg/ml as measured by cell viability, and DE inhibited LPS-induced cell morphological changes as measured by inverted microscopy. In survival experiments, DE at 25 µg/ml had no toxicity to zebrafish larvae. By using an enzymatic standard assay, DE reduced the production of nitric oxide (NO) in LPS-induced RAW264.7 cells. Fluorescence microscopy results show that DE reduced LPS-induced ROS production and apoptosis in RAW264.7 cells. DE also inhibited CuSO4-induced ROS production and neutrophil aggregation in zebrafish larvae. The results of flow cytometry show that DE alleviated the LPS-induced cell cycle arrest. In LPS-induced RAW264.7 cells, RT-PCR revealed that DE decreased the expression of M1 phenotypic genes iNOS, IL-6, and IL-1ß while increasing the expression of M2 phenotypic genes IL-10 and CD206. Furthermore, in CuSO4-induced zebrafish larvae, DE reduced the expression of iNOS, TNF-α, IL-6, and IL-10. The findings suggest that DE reduces the LPS-induced inflammatory response in RAW264.7 cells by regulating polarization and apoptosis. DE also reduces the CuSO4-induced inflammatory response in zebrafish larvae.

Impact of high dietary cornstarch level on growth, antioxidant response, and immune status in GIFT tilapia Oreochromis niloticus.

This study was conducted to investigate the relationship between different cornstarch levels in tilapia diet and immune function. All test fish were fed with three cornstarch levels: low-cornstarch (0, LS), medium-cornstarch (18%, MS) and high-cornstarch (36%, HS) diets. Three hundred and sixty fish (initial mean body weight 31.73 ± 1.36 g) were randomly allocated into twelve water-circulated tanks, and thirty fish per tank. Compared with the low and medium cornstarch diets, the results of growth showed that the high cornstarch diet significantly decreased the FBW, WGR, and SGR, and increased the FCR of tilapia (P < 0.05). The high cornstarch diet significantly decreased the content of crude protein and increased the content of crude lipid in whole body composition (P < 0.05). Moreover, the VSI and CF in HS diet were significantly higher than those of LS diet (P < 0.05). The results of blood biochemical index exhibited that the HS diet significantly increased the content of blood glucose, and liver/muscle glycogen (P < 0.05). The results of antioxidant experiments demonstrated that the content of SOD and T-AOC in MS diet were significantly higher than those of HS diet (P < 0.05). Meanwhile, the content of MDA in MS diet was significantly lower than that of HS diet (P < 0.05). The results of immune index test showed that the lysozyme activities in the serum, liver, and gill, and the phagocytic activity and index in MS diet were significantly higher than those of HS diet (P < 0.05). The challenge assay results revealed that the mortality rate of HS diet was higher than those of LS and MS diets, but the difference was not significant (P > 0.05). In conclusion, the overall results suggested that the 36% cornstarch diet reduced not only the growth performance, but also body immunity. Under this experimental condition, GIFT tilapia could tolerate 18% cornstarch, but not 36% cornstarch.

Rosiglitazone promotes glucose metabolism of GIFT tilapia based on the PI3K/Akt signaling pathway.

The study aimed to explore the effects of rosiglitazone on glucose metabolism of GIFT tilapia based on the PI3K/Akt signaling pathway. The experiment was divided into five groups: normal starch group (32%, LC), high starch group (53%, HC), high starch +rosiglitazone group 1 (10 mg/kg, R1), high starch + rosiglitazone group 2 (20 mg/kg, R2), and high starch + rosiglitazone group 3 (30 mg/kg, R3). The results showed that a high starch diet supplemented with 10-20 mg/kg rosiglitazone had a better specific growth rate and protein efficiency that was beneficial for the growth of the tilapia. Rosiglitazone had no significant effect on the contents of crude lipid, crude protein, crude ash, and moisture of the whole fish body (p > 0.05). The contents of triglycerides and total cholesterol in the R1, R2, and R3 groups were lower than those in the HC group. The levels of glutamic oxaloacetic transaminase (GOT) and glutamic pyruvic transaminase (GPT) in R1 and R2 groups were significantly lower than those in the HC groups (p < 0.05). However, the GOT and GPT levels in the R3 groups were significantly higher than those in the R1 and R2 groups (p < 0.05). With an increase in the rosiglitazone concentration, the contents of serum glucose, insulin, and hepatic glycogen in the R1, R2, and R3 groups decreased gradually. Meanwhile, the muscle glycogen content in the R1, R2, and R3 groups increased gradually. The mRNA expression of the IRS-1, PI3K, GLUT-4, and Akt proteins in the R1, R2, and R3 groups was significantly higher than that in the HC group (p < 0.05). Compared with the HC group, the expression of the GSK-3 mRNA in the R1, R2, and R3 groups was significantly reduced (p < 0.05). The protein expression of p-Akt in the R1 and R2 groups was higher than that in the HC group (p > 0.05). The protein expression of p-GSK-3ß in the R1 and R2 groups was significantly higher than that in the HC group (p < 0.05). In conclusion, a high starch diet supplemented with rosiglitazone can improve growth, enhance the serum biochemical indices, and increase the muscle glycogen content in the GIFT tilapia. It benefits in upregulating the IRS-1, PI3K, and GLUT-4 mRNA levels in the skeletal muscle and promotes glucose uptake. Meanwhile, the phosphorylation of Akt and GSK-3ß increased significantly and resulted in the inactivation of GSK-3ß and alleviation of insulin resistance.

Effects of different molar mass chitooligosaccharides on growth, antioxidant capacity, non-specific immune response, and resistance to Aeromonas hydrophila in GIFT tilapia Oreochromis niloticus.

A feeding trial was conducted to evaluate the effects of different molar mass chitooligosaccharides (1000 Da, 3000 Da and 8000 Da) on growth, antioxidant capacity, non-specific immune response, and resistance to Aeromonas hydrophila in GIFT tilapia (Oreochromis niloticus). A total of 600 fish were divided into four treatments with five replicates of thirty fish per tank. The results showed that the supplementation of 1000 Da and 3000 Da COS significantly improved the growth performance and feed utilization in GIFT tilapia. The trend of decreasing total cholesterol, triglyceride, ALT, and ACP activity was observed in fish fed diet supplemented COS. The supplementation of 1000 Da and 3000 Da COS significantly improved the serum TAC activity, and decreased the serum MDA and catalase activities (P < 0.05). The lysozyme activity of blood, liver, and gills in fish fed diets supplemented with 1000 Da and 3000 Da COS was significantly higher than that of fish fed control diet after 56 days of feeding (P < 0.05). The phagocytic activity and phagocytic index of fish fed diets supplemented with 1000 Da and 3000 Da COS were significantly higher than those of fish fed control diet. Post-challenge test showed that fish mortality in 1000 Da, 3000 Da, and 8000 Da COS groups were significantly lower than that of fish in control group (P < 0.05). In conclusion, the present study indicated that dietary 1000 Da and 3000 Da COS supplementation could enhance more performance and immune response of GIFT tilapia than 8000 Da COS.

An evaluation of mixed plant protein in the diet of Yellow River carp (Cyprinus carpio): growth, body composition, biochemical parameters, and growth hormone/insulin-like growth factor 1.

The aim of this work is to evaluate the effects of dietary inclusion of mixed plant protein (MP) (rapeseed meal:cottonseed meal:peanut meal = 1:1:1) on growth, body composition, blood biochemical parameters, growth hormone/insulin-like growth factor 1, and relative non-specific immune response in Yellow River carp Cyprinus carpio. Five isonitrogenous and isoenergetic trial diets were formulated to replace fish meal at 0 (MP0, control), 25% (MP25), 50% (MP50), 75% (MP75), and 100% (MP100) mixed plant protein, respectively. The 25% mixed plant protein did not affect the weight gain, specific growth rate, and protein efficiency ratio, whereas these parameters were depressed by 50% and above mixed plant protein. The whole body protein content gradually decreased with increasing dietary MP; meanwhile, the whole body lipid content is the opposite. The MP75 and MP100 diets adversely affected the glucose level, total cholesterol value, alanine transaminase, and aspartate transaminase activity of serum. Fish fed MP75 and MP100 diets showed higher growth hormone level than that of MP0 diet; however, the insulin-like growth factor 1 level got the opposite result. The 50% and above inclusion of MP decreased lysozyme activity and increased malondialdehyde content. In conclusion, no more than 50% of fish meal could be replaced by mixed plant protein in diet. However, 50% and above inclusion of mixed plant protein in diet could depress the growth, insulin-like growth factor 1 level, and non-specific immune response, and significantly affect the whole body composition and serum biochemical parameters in Yellow River carp.