Phloroglucinol derivatives, coumarins and an alkaloid from the roots of Evodia lepta Merr.

Two previously undescribed phloroglucinol derivatives [(±) evolephloroglucinols A and B], five unusual coumarins [evolecoumarins A and B and (±) evolecoumarins C-E], and one novel enantiomeric quinoline-type alkaloid [(±) evolealkaloid A], along with 20 known compounds, were isolated from the EtOH extract of the roots of Evodia lepta Merr. Their structures were elucidated by extensive spectroscopic analyses. The absolute configurations of the undescribed compounds were determined by X-ray diffraction or computational calculations. Their anti-neuroinflammatory effects were assayed. Among the identified compounds, compound 5a effectively reduced nitric oxide (NO) production with an EC50 value of 22.08 ± 0.46 µM. Hence, it could indeed inhibit the lipopolysaccharide (LPS)-induced Nod-like receptor family, pyrin domain containing 3 (NLRP3) inflammasome.

Hydroxysafflor Yellow A Exerts Neuroprotective Effect by Reducing Aß Toxicity Through Inhibiting Endoplasmic Reticulum Stress in Oxygen-Glucose Deprivation/Reperfusion Cell Model.

Ischemia stroke is thought to be one of the vascular risks associated with neurodegenerative diseases, such as Alzheimer's disease (AD). Hydroxysafflor yellow A (HSYA) has been reported to protect against stroke and AD, while the underlying mechanism remains unclear. In this study, SH-SY5Y cell model treated with oxygen-glucose deprivation/reperfusion (OGD/R) was used to explore the potential mechanism of HSYA. Results from cell counting kit-8 (CCK-8) showed that 10 µM HSYA restored the cell viability after OGD 2 hours/R 24 hours. HSYA reduced the levels of malondialdehyde and reactive oxygen species, while improved the levels of superoxide dismutase and glutathione peroxidase. Furthermore, apoptosis was inhibited, and the expression of brain-derived neurotrophic factor was improved after HSYA treatment. In addition, the expression levels of amyloid-ß peptides (Aß) and BACE1 were decreased by HSYA, as well as the expression levels of binding immunoglobulin heavy chain protein, PKR-like endoplasmic reticulum (ER) kinase pathway, and activating transcription factor 6 pathway, whereas the expression level of protein disulfide isomerase was increased. Based on these results, HSYA might reduce Aß toxicity after OGD/R by interfering with apoptosis, oxidation, and neurotrophic factors, as well as relieving ER stress.

Flavonoid-containing supplements for preventing acute respiratory tract infections: A systematic review and meta-analysis of 20 randomized controlled trials.

BACKGROUND: This systematic review and meta-analysis was conducted to investigate the efficacy and safety of flavonoid-containing supplements in preventing acute respiratory tract infection (ARTI). METHODS: Randomized controlled trials (RCTs) investigating the effects of flavonoid-containing supplements on ARTI prevention in the aspects of ARTI incidence, mean ARTI sick days, symptoms, bio-immune markers, and adverse effects were searched in 5 databases. Data were searched from inception to November 26, 2021. Stata 16.0 was used to perform the meta-analysis. RESULTS: Twenty RCTs (n = 4521) were included in this systematic review and meta-analysis. Pooled results showed that in the flavonoid-containing supplement group, the ARTI incidence and mean ARTI sick days were significantly decreased compared to those in the control group (RR = 0.81, 95% CI: 0.74-0.89, p < 0.001; WMD = -0.56, 95% CI: -1.04 to -0.08, p = 0.021; respectively). In 8 RCTs, flavonoids were singly used for interventions, ARTI incidence in the experimental group significantly decreased compared to that in the control group (RR = 0.85, 95% CI: 0.72-1.00, p = 0.047). In ten RCTs, flavonoid-containing mixtures were applied for interventions, and ARTI incidence in the experimental group significantly decreased compared to that in the control group (RR = 0.79, 95% CI: 0.71-0.89, p < 0.001). Furthermore, the ARTI incidence and mean ARTI sick days were significantly decreased in the experimental group compared to those in the control group in the flavan-3-ols subgroup (RR = 0.79, 95% CI: 0.67-0.92, p = 0.002; WMD = -2.75, 95% CI: -4.30 to -1.21, p < 0.001; respectively) and the multiple subclasses subgroup (RR = 0.75, 95% CI: 0.63-0.88, p = 0.001; WMD = -0.56, 95% CI: -1.11 to -0.01, p = 0.046; respectively). However, the bio-immune markers including interleukin-6, hypersensitive-c-reactive-protein, tumor necrosis factor-α, and interferon-γ did not differ between the flavonoid group and the control group. Moreover, in the flavonoid-containing supplement group, the incidence of adverse reactions did not increase compared to that in the control group (RR = 1.16, 95% CI: 0.78-1.73, p = 0.469). CONCLUSIONS: This systematic review and meta-analysis showed that flavonoid-containing supplements were efficacious and safe in preventing ARTIs. The most important limitations result from the small number of trials, poor quality of some included RCTs, differences in the composition and types of interventions, principal subclasses of flavonoids, methods of administration, and methodology. Moreover, only a few RCTs conducted independent verification of the flavonoid supplements used in the trial in terms of purity and potency, which may lead to a potential source of bias. Thus, larger and better-designed studies are needed to further verify this conclusion.

[Role of m 6A Reader YTHDC2 in Differentiation of Human Bone Marrow Mesenchymal Stem Cells].

OBJECTIVE: To study the regulatory effect of YTH domain-containing protein 2 (YTHDC2), a member of N 6-methyladenosine (m 6A) readers, on the osteogenic or adipogenic differentiation of human bone marrow mesenchymal stem cells (hBMSCs). METHODS: YTHDC2 expression was knocked down by small interfering RNA (siRNA) in vitro. Osteogenic differentiation and adipogenic differentiation of hBMSCs were induced after YTHDC2 knockdown in order to study the changes in the differentiation phenotype of hBMSCs. Alkaline phosphatase staining (ALP staining) and alizarin red S staining were performed to examine osteogenic activity and calcium-nodular formation. Nile red staining was performed to examine lipid-droplet formation. Real-time quantitative polymerase chain reaction (RT-qPCR) was used to assess the expression of osteogenesis and adipogenesis-related genes. RNA-sequencing was performed to identify the transcriptome changes after YTHDC2 knockdown and to explore the potential regulatory mechanism by which YTHDC2 regulated the diferentiation of hBMSCs. RESULTS: In this study, we found that siRNA-induced YTHDC2 knockdown resulted in increased ALP activity and calcium-nodular formation of hBMSCs during osteogenic differentiation, and significantly upregulated the expression of osteogenesis-related genes. In addition, the lipid-droplet formation capacity of hBMSCs was decreased during adipogenic differentiation. The expression of adipogenesis-related genes was significantly down-regulated. Gene-set enrichmen analysis of RNA-seq data showed that YTHDC2 was significantly correlated with ribosome function and mRNA-translation-related signaling pathways. CONCLUSION: The findings indicate that YTHDC2 knockdown can promote the osteogenic differentiation of hBMSCs and inhibit the adipogenic differentiation. YTHDC2 knockdown may cause changes in ribosome function.