Rehmannia glutinosa Polysaccharides: Optimization of the Decolorization Process and Antioxidant and Anti-Inflammatory Effects in LPS-Stimulated Porcine Intestinal Epithelial Cells

Abstract

Polysaccharide decolorization has a major effect on polysaccharide function. In the present study, the decolorization of Rehmannia glutinosa polysaccharides (RGP) is optimized using two methods—the AB-8 macroporous resin (RGP-1) method and the H2O2 (RGP-2) method. The optimal decolorization parameters for the AB-8 macroporous resin method were as follows: temperature, 50 °C; macroporous resin addition, 8.4%; decolorization duration, 64 min; and pH, 5. Under these conditions, the overall score was 65.29 ± 3.4%. The optimal decolorization conditions for the H2O2 method were as follows: temperature, 51 °C; H2O2 addition, 9.5%; decolorization duration, 2 h; and pH, 8.6. Under these conditions, the overall score was 79.29 ± 4.8%. Two pure polysaccharides (RGP-1-A and RGP-2-A) were isolated from RGP-1 and RGP-2. Subsequently, their antioxidant and anti-inflammatory effects and mechanisms were evaluated. RGP treatment activated the Nrf2/Keap1 pathway and significantly increased the activity of antioxidant enzymes (p < 0.05). It also inhibited the expression of pro-inflammatory factors and suppressed the TLR4/NF-κB pathway (p < 0.05). RGP-1-A had a significantly better protective effect than RGP-2-A, likely owing to the sulfate and uronic groups it contains. Together, the findings indicate that RGP can act as a natural agent for the prevention of oxidation and inflammation-related diseases.

Renal and survival benefits of seventeen prescribed Chinese herbal medicines against oxidative-inflammatory stress in systemic lupus erythematosus patients with chronic kidney disease: a real-world longitudinal study

“…[Orobanchaceae; Radix Rehmannia (Sheng-Di-Huang), esteemed for its capacity to purge pathogenic heat from blood and enrich Yin per Chinese medical doctrine ( Zhang et al, 2008 ), is prevalent in many SLE prescriptions like Liu-Wei-Di-Huang-Wan and Zhi-Bai-Di-Huang-Wan ( Ma et al, 2016 ; Chang et al, 2017 ). Its primary active element has proven to activate the Nrf2/Keap1 route and suppress pro-inflammatory factor expression, thus assuming dual roles as anti-inflammatory and antioxidant agents ( Ren et al, 2023 ). Sheng-Di-Huang’s ( Rehmannia glutinosa (Gaertn.)…”

Subsequent maternal sleep deprivation aggravates neurobehavioral abnormalities, inflammation, and synaptic function in adult male mice exposed to prenatal inflammation

“…The binding of LPS to Toll-like receptor 4 (TLR4) triggers an inflammatory response ( Ren et al, 2023 ; Tongaonkar et al, 2023 ). One study showed that exposure to LPS activated the TLR4 signaling pathway and microglia in pregnant mice and led to autism-like behavior in the offspring ( Xiao et al, 2021 ).…”

Ajugol's upregulation of TFEB-mediated autophagy alleviates endoplasmic reticulum stress in chondrocytes and retards osteoarthritis progression in a mouse model

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