Quercetin effectively improves LPS-induced intestinal inflammation, pyroptosis, and disruption of the barrier function through the TLR4/NF-κB/NLRP3 signaling pathway in vivo and in vitro.

Background: Inflammatory bowel diseases are characterized by the alterations of the mucosa and gastrointestinal physiology, and the core of these alterations is endothelial cells. Quercetin is a flavonoid presents in some traditional Chinese medicine, plants, and fruits. Its protective effects in several gastrointestinal tumors have been demonstrated, but its effects on bacterial enteritis and pyroptosis-related diseases have rarely been studied. Objective: This study aimed to evaluate the effect of quercetin on bacterial enteritis and pyroptosis. Design: In vitro experiments were performed using rat intestinal microvascular endothelial cells divided into seven groups: control group (no treatment), model group (10 µg/mL lipopolysaccharide (LPS)+1 mM adenosine triphosphate [ATP]), LPS group (10 µg/mL LPS), ATP group (1 mM ATP), and treatment groups (10 µg/mL LPS+1 mM ATP and 5, 10, and 20 µM quercetin). The expression of pyroptosis-associated proteins, inflammatory factors, tight junction proteins, and the percentage of late apoptotic and necrotic cells were measured. In vivo analysis was performed using specific pathogen-free Kunming mice pretreated with quercetin and the water extract of Cacumen Platycladi for 2 weeks followed by 6 mg/kg LPS on day 15. Inflammation in the blood and intestinal pathological changes were evaluated. Results: Quercetin used in vitro significantly reduced the expression of Toll-like receptor 4 (TLR4), NOD-like receptor 3 (NLRP3), caspase-1, gasdermin D, interleukin (IL)-1ß, IL-18, IL-6, and tumor necrosis factor-α. It also inhibited phosphorylation of nuclear factor-kappa B (NF-κB) p65 and increased cell migration and the expression of zonula occludens 1 and claudins, while reduced the number of late apoptotic cells. The in vivo results showed that Cacumen Platycladi and quercetin significantly reduced inflammation, protected the structure of the colon and cecum, and prevent fecal occult blood induced by LPS. Conclusions: These findings suggested the ability of quercetin to reduce inflammation induced by LPS and pyroptosis through TLR4/NF-κB/NLRP3 pathway.

Tetrahydroxystilbene Glucoside Regulates Proliferation, Differentiation, and OPG/RANKL/M-CSF Expression in MC3T3-E1 Cells via the PI3K/Akt Pathway.

Tetrahydroxystilbene glucoside (TSG) is a unique component of the bone-reinforcing herb Radix Polygoni Multiflori Preparata (RPMP). It has the ability to promote bone formation and protect osteoblasts. However, the underlying mechanism remains unclear. To better understand its biological function, we determined TSG's effect on murine pre-osteoblastic MC3T3-E1 cells by the MTT assay, flow cytometry, FQ-PCR, Western blot, and ELISA. The results showed that TSG caused an elevation of the MC3T3-E1 cell number, the number of cells in the S phase, and the mRNA levels of the runt-related transcription factor-2 (Runx2), osterix (Osx), and collagen type I α1 (Col1a1). In addition, the osteoprotegerin (OPG) mRNA level was up-regulated, while the nuclear factor-κB ligand (RANKL) and macrophage colony-stimulating factor (M-CSF) mRNA levels were down-regulated by TSG. Furthermore, TSG activated the phosphoinosmde-3-kinase/protein kinase B (also known as PI3K/Akt) pathway, and blocking this pathway by the inhibitor LY-294002 could impair TSG's functions in relation to the MC3T3-E1 cells. In conclusion, TSG could activate the PI3K/Akt pathway and thus promote MC3T3-E1 cell proliferation and differentiation, and influence OPG/RANKL/M-CSF expression. TSG merits further investigation as a potential therapeutic agent for osteoporosis treatment.

Effect of Fructus Ligustri Lucidi on osteoblastic like cell-line MC3T3-E1.

UNLABELLED: Fructus Ligustri Lucidi, fruits of Ligustrum lucidum Ait. (Oleaceae), has the effects of tonifying the liver and the kidney and strengthening the bones and muscles. In ancient times, Fructus Ligustri Lucidi can be prepared in ethanol or in water. Some active compounds have been found in Fructus Ligustri Lucidi, like Oleanolic acid and Ursolic acid, and Ursolic acid were proved to have osteogenic effects. METHODS AND RESULTS: To prove that Fructus Ligustri Lucidi water extract have osteogenic effects on MC3T3-E1 cells and how these effects work, we used CCK-8 (cell counting kit-8), ELISA (enzyme-linked immunosorbent assay), FQ-PCR (realtime fluorescence quantitative PCR) and western blot assays. After treatment with Fructus Ligustri Lucidi for 48h, 72h, 96h, the cell viability was marked increased, on concentration-dependently and time-dependently pattern. High and low concentrations of Fructus Ligustri Lucidi promoted differentiation of cells. Fructus Ligustri Lucidi could up-regulate OPG and RANKL protein in supernatant at 48h and 72h except for highest concentration (10(-1)mg/ml). Fructus Ligustri Lucidi promote OPG and RANKL mRNA expression at 48h and 72h, while the level of promoting at 72 was higher than 48h. 10(-5)mg/ml of Fructus Ligustri Lucidi up-regulates OPG protein expression and down-regulates RANKL protein expression. After treatment with Fructus Ligustri Lucidi water extract, inhibitors, Fructus Ligustri Lucidi water extract with inhibitors for 72h, inhibitors PD 98059, SB 203580, SP600125 and LY 294002 showed Fructus Ligustri Lucidi-induced cell proliferation and the leakage of OPG proteins effects. Fructus Ligustri Lucidi promoted the protein levels of ERK, p-ERK, p-JNK, p38, pp38, AKT and p-AKT, and inhibited the protein levels of JNK. CONCLUSIONS: Fructus Ligustri Lucidi water extract promoted cell proliferation and differentiation, mRNA and protein expression of OPG and RANKL on MC3T3-E1 cells. The effects of cell proliferation and leakage of OPG related to MAPK and AKT signaling pathways in different ways.

[Observation on therapeutic effect of blood-letting therapy on apoplectic hemiplegia numbness syndrome].

OBJECTIVE: To observe therapeutic effect of blood-letting therapy on apoplectic hemiplegia numbness syndrome and search for clinically effective therapy. METHODS: Ninety and five cases of apoplectic hemiplegia were randomly divided into a treatment group of 55 cases and a control group of 40 cases in order of visiting. The treatment group were treated with tapping Huatuo Jiaji (EX-B2) on the back by plum-blossom needle combined with blood-letting on twelve Well-points or Shixuan (EX-UE 11), once every day, 6 times constituting one course; the control group were treated with routine acupuncture at points of the four limbs, once daily, 12 times constituting one course. After they were treated for 4 courses, their therapeutic effects were observed. RESULTS: The total effective rate was 94.5% in the treatment group and 77.5% in the control group with a significant difference between the two groups (P < 0.01). CONCLUSION: Blood-letting therapy is an effective therapy for post-apoplectic hemiplegia numbness syndrome.