Immunomodulatory and antioxidant effects of Glycyrrhiza uralensis polysaccharide in Lohmann Brown chickens

Abstract

Glycyrrhiza polysaccharide extract 1 (GPS-1) is a bioactive component isolated from Glycyrrhiza uralensis, also known as Chinese licorice. It appears to be pharmacologically active as an antibacterial, antiviral, and anti-tumor agent. GPS-1 has also been shown to buffer liver health and regulate the immune system. Moreover, GPS-1 is low cost and easy to extract. More study was needed to elucidate the biochemical pathways underlying the immunomodulatory and antioxidant benefits observed in Glycyrrhiza polysaccharide extract 1 (GPS-1). in vitro experiments on chicken lymphocytes and dendritic cells (DCs) show that GPS-1 significantly promotes the proliferation of immune cells and is linked to lymphocytes' secretion of IL-12, IFN-γ, and TNF-α by. DC secretion of NO, IL-2, IL-1β, IFN-γ, TNF-α, and IL-12p70 was also increased significantly. Additionally, GPS-1 also displayed a significant antioxidant effect in vitro, able to scavenge DPPH, hydrogen peroxide, ABTS, and other free radicals like superoxide anions. Separately, GPS-1 was tested in vivo in combination with the Newcastle disease virus (NDV) – attenuated vaccine. 120 Lohmann Brown chickens were vaccinated, while another 30 became the unvaccinated blank control (BC) group. For three consecutive days 1 mL of GPS-1 was administered at doses of 19.53 μg/mL, 9.77 μg/mL, or 4.88 μg/mL to the ND-vaccinated birds, except for the vaccine control (VC), where n = 30 per group. In vivo results show that GPS-1 combined with Newcastle disease (ND) vaccine had the best efficacy at significantly increasing chickens' body weight and ND serum antibody titer, enhancing their secretion of IL-2 and IFN- γ, and promoting the development of immune organs. The results also indicate that GPS-1 was able increase the proliferation of in vitro immune cells and elevate their cytokine secretion, which enhances the body's immune response. GPS-1 also clearly has the potential to be used as an immune adjuvant alongside ND vaccination.

Effects of glycyrrhiza polysaccharides on growth performance, meat quality, serum parameters and growth/meat quality-related gene expression in broilers

“…It is currently believed that this result is due to the suppression of hydroperoxide production (67). Previous studies have demonstrated that GP has a notable ability to scavenge free radicals, including DPPH, hydrogen peroxide, ABTS, and superoxide anion radicals (19), which well explains our findings. Notably, the maximum TBARS value in fresh meat is 1.0 mg MDA/kg (68), yet the shown TBARS values in our study were all above 2.0 mg MDA/kg.…”

“…At 42 d of the trial, when the GP supplementation exceeded 1,000 mg/kg, there was a significant increase in GLB concentration, suggesting that GP might affect the immune function of broilers in the later stages of growth. Zhou et al had reported that GP significantly enhanced the serum antibody titer in Lohmann Brown chickens, promoted the development of immune organs and proliferation of immune cells and stimulated lymphocytes and dendritic cells to secrete relevant cytokines (19). Wu et al (48) demonstrated that the synergistic effect of GP with the NDV vaccine in chickens led to the production of an increased number of Newcastle disease antibodies, which held significant importance in the prevention of Newcastle disease.…”

“…Furthermore, GP molecules are abundant in reducing ends, and their conformation predominantly features α-D-pyranose. These structural characteristics enable GP to exhibit various pharmacological activities (15), such as promoting growth (16), enhancing immunity (17), exerting anti-inflammatory (18), and antioxidant effects (19).…”

Glycyrrhiza polysaccharides inhibits PRRSV replication

“…Its complex chemical structure makes it have many functions. It has been proven to enhance and regulate the body's immunity [ 7 ], be antibacterial [ 8 ], inhibit tumor growth [ 9 ], have antioxidant and other effects [ 10 ], and is often widely used as a feed additive in the aquaculture industry. In addition, it also has a strong antiviral effect and can significantly inhibit the invasion and proliferation of the virus.…”

Protective Effects of Glycyrrhiza Total Flavones on Liver Injury Induced by Streptococcus agalactiae in Tilapia (Oreochromis niloticus)

“…Liu studied the antibacterial activity of licorice extract, and found that oleic acid, dehydrocyrrhizin D, glycyrrhetinic acid had a good inhibitory effect on Streptococcus mutans, Escherichia coli, Bacillus subtilis and other bacteria [ 17 ]. Recent studies have found that GTF have good anti-inflammatory, antibacterial and antiviral effects [ 18 , 19 , 20 ]. However, there has been no relevant report on whether GTFs have an antibacterial effect on tilapia Streptococcus.…”