Immune-Enhancing Effects of a Novel Glucan from Purple Sweet Potato Ipomoea batatas (L.) Lam on RAW264.7 Macrophage Cells via TLR2- and TLR4-Mediated Pathways

Abstract

PSPP-1 was obtained from purple sweet potato, and the effects of PSPP-1 on the immune modulation on macrophage cells were investigated for the first time. PSPP-1 promoted RAW264.7 proliferation and increased the total cell percentage in DNA synthesis and mitosis phases, and the cell morphology changed in volume and appearance. Additionally, the RAW264.7 immune functions of phagocytic activity and nitric oxide, reactive oxygen species, and cytokine production were improved by PSPP-1. The western blot experiment showed that PSPP-1 could activate toll-like receptor 2 and toll-like receptor 4-mediated pathways, and the expressions of proteins in MyD88-dependent, mitogen-activated protein kinase (MAPK)-signaling, NF-κB-signaling, AP-1 signaling, and TRIF-dependent pathways were improved markedly. Molecular docking and Biolayer Interferometry study further indicated that PSPP-1 could recognize and bind TLR2 and TLR4 by targeting the binding sites with a strong affinity. It suggested that PSPP-1 could enhance immunity via TLR2- and TLR4-mediated pathways, and it could be explored as an immunomodulatory agent.

Immunomodulatory effects of Abelmoschus esculentus water extract through MAPK and NF-κB signaling in RAW 264.7 cells

“… 6 A number of downstream signaling pathways, including the nuclear factor κB (NF-κB) and mitogen-activated protein kinase (MAPK) pathways, are triggered by various adapter complexes that interact with TLR4, resulting in the production of nitric oxide (NO) and inflammatory cytokines/chemokines. 7 Foreign antigens are phagocytosed by macrophages, while inflammatory factors, such as NO and the pro-inflammatory cytokines tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β), are secreted, increasing phagocytosis and inducing innate immune activity via natural killer cells and dendritic cells. 8 , 9 Therefore, macrophages are known to contribute to the activation of adaptive immunity by recognizing foreign antigens and presenting them to T cells to regulate cell activation and differentiation.…”

Euonymus alatus (Thunb.) Siebold leaf extract enhanced immunostimulatory effects in a cyclophosphamide-induced immunosuppressed rat model

“…The activation of LPS-induced macrophages produces proinflammatory cytokines, such as IL-1, TNF-α, IL-6, and IFN-γ and induces MAPK-dependent phosphorylation of p38, c-Jun NH2-terminal kinase (JNK), and ERK (28)(29)(30). Additionally, NF-κB is a major activator for the TNF-α production in macrophages and is known to play a major role in controlling the expression of proteins involved in immune, inflammatory, and acute-phase responses (30)(31)(32). MAPK and NF-κB signaling play critical roles in the immune response (28)(29)(30)(31)(32).…”

Chemical Characterization and Atherosclerosis Alleviation Effects of Gypenosides from Gynostemma pentaphyllum through Ameliorating Endothelial Dysfunction via the PCSK9/LOX-1 Pathway

“…The size of the docking station was set through GridBox, and the coordinate values were as follows: – 64.934, 48.756, and −23.175. Each of the substances presented in Figure was converted to the pdbqt format by AutoDock Tools 1.5.7 software and then docked to the enzyme using AutoDock Vina 1.1.2 software with default values for most parameters . Docking results are shown in Tables S1–S4.…”

“…Each of the substances presented in Figure 7 was converted to the pdbqt format by AutoDock Tools 1.5.7 software and then docked to the enzyme using AutoDock Vina 1.1.2 software with default values for most parameters. 40 Docking results are shown in Tables S1−S4.…”