Myricetin possesses the potency against SARS-CoV-2 infection through blocking viral-entry facilitators and suppressing inflammation in rats and mice.

BACKGROUND: Myricetin (3,5,7-trihydroxy-2-(3,4,5-tri hydroxyphenyl)-4-benzopyrone) is a common flavonol extracted from many natural plants and Chinese herb medicines and has been demonstrated to have multiple pharmacological activities, such as anti-microbial, anti-thrombotic, neuroprotective, and anti-inflammatory effects. Previously, myricetin was reported to target Mpro and 3CL-Pro-enzymatic activity to SARS-CoV-2. However, the protective value of myricetin on SARS-Cov-2 infection through viral-entry facilitators has not yet been comprehensively understood. PURPOSE: The aim of the current study was to evaluate the pharmacological efficacy and the mechanisms of action of myricetin against SARS-CoV-2 infection both in vitro and in vivo. METHODS: The inhibitory effects of myricetin on SARS-CoV-2 infection and replication were assessed on Vero E6 cells. Molecular docking analysis and bilayer interferometry (BLI) assays, immunocytochemistry (ICC), and pseudoviruses assays were performed to evaluate the roles of myricetin in the intermolecular interaction between the receptor binding domain (RBD) of the SARS-CoV-2 spike (S) protein and angiotensin-converting enzyme 2 (ACE2). The anti-inflammatory potency and mechanisms of myricetin were examined in THP1 macrophages in vitro, as well as in carrageenan-induced paw edema, delayed-type hypersensitivity (DTH) induced auricle edema, and LPS-induced acute lung injury (ALI) animal models. RESULTS: The results showed that myricetin was able to inhibit binding between the RBD of the SARS-CoV-2 S protein and ACE2 through molecular docking analysis and BLI assay, demonstrating its potential as a viral-entry facilitator blocker. Myricetin could also significantly inhibit SASR-CoV-2 infection and replication in Vero E6 cells (EC50 55.18 µM), which was further validated with pseudoviruses containing the RBD (wild-type, N501Y, N439K, Y453F) and an S1 glycoprotein mutant (S-D614G). Moreover, myricetin exhibited a marked suppressive action on the receptor-interacting serine/threonine protein kinase 1 (RIPK1)-driven inflammation and NF-kappa B signaling in THP1 macrophages. In animal model studies, myricetin notably ameliorated carrageenan-induced paw edema in rats, DTH induced auricle edema in mice, and LPS-induced ALI in mice. CONCLUSION: Our findings showed that myricetin inhibited HCoV-229E and SARS-CoV-2 replication in vitro, blocked SARS-CoV-2 virus entry facilitators and relieved inflammation through the RIPK1/NF-κB pathway, suggesting that this flavonol has the potential to be developed as a therapeutic agent against COVID-19.

Deciphering the molecular mechanisms of Maxing Huoqiao Decoction in treating pulmonary fibrosis via transcriptional profiling and circRNA-miRNA-mRNA network analysis.

BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive, fibrotic interstitial lung condition with unknown etiology and high mortality. Chinese herbal medicine has been used for more than a thousand years to treat various lung diseases. PURPOSE: The current study aimed to examine whether Chinese herbal Maxing Huoqiao Decoction (MXHQD) exerts therapeutic effects on IPF and to further uncover its underlying molecular mechanisms. METHODS: Mouse model of acute lung injury (ALI) or IPF was induced by intratracheal instillation of LPS or bleomycin, respectively. ALI mice were treated with MXHQD for 7 days, and lung tissues were taken for test after modeling 24 h. IPF mice were gavaged for 21 days after modeling. Lung tissues were subjected to whole transcriptome detection, and the differential RNAs were experimentally verified. RESULTS: The results showed that MXHQD alleviated the computed tomography (CT) and the pathological degree changes in mice with IPF, improved changes in the expression of fibrosis related genes and reduced the hydroxyproline expression in IPF mice. MXHQD also decreased the cell numbers in bronchoalveolar lavage fluids, and the expression levels of the inflammatory factors in the ALI mice lung tissues were significantly inhibited. By applying whole transcriptome analysis, results showed that MXHQD acted on 40 mRNAs, 15 miRNAs, 25 novel lncRNAs and 17 circRNAs to resist pulmonary fibrosis. The competing endogenous RNA (ceRNA) network diagram showed that the multiple components of MXHQD against fibrosis through a network of multiple targets. The differential mRNAs were mainly related to the innate immune response and the defense response to virus. Then the expression of mRNAs in the differential mRNA-miRNA-differential circRNA network in the lung tissue of IPF was verified. The expression of ZBP1 and ISG15 related to immune system and anti virus was verified at both gene and protein expressions. MXHQD could significantly inhibit the elevation of ZBP1 and ISG15 factors induced by the fibrosis model. CONCLUSION: Overall, our findings provide compelling evidence that MXHQD can alleviate IPF by modulating innate immunity. This is the first study to reveal the molecular mechanism underlying the multi-components, multi-channels and multi-targets anti-IPF immune injury of MXHQD, and supports its potential clinical application for IPF.

Integrated RNA-sequencing and network pharmacology approach reveals the protection of Yiqi Huoxue formula against idiopathic pulmonary fibrosis by interfering with core transcription factors.

BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is a refractory disease. Therefore, developing effective therapies for IPF is the need of the hour. PURPOSE: Yiqi Huoxue Formula (YQHX) is an herbal formula comprising three herbal medicines: Ligusticum chuanxiong Hort. (Chuanxiong Rhizoma, CR), Panax notoginseng (Burk.) F. H. Chen (Notoginseng Radix Et Rhizoma, NR) and Panax ginseng C. A. Mey. (Ginseng Radix Et Rhizoma, GR). This study aims to determine the anti-pulmonary fibrosis effect of YQHX and explore its mechanism of action. STUDY: Design and Methods: The chemical components in the GR, CR and NR extracts were identified by High Performance Liquid Chromatography. A TGF-ß1-induced myofibroblast cell model was used to test the anti-fibrosis effect of GR, CR, NR and YQHX. RNA-sequencing was used to identify the differentially expressed genes (DEGs) after YQHX treatment. Subsequently, gene enrichment analysis and key transcription factors (TFs) prediction for YQHX-regulated DEGs was performed. The active constituents of GR, CR and NR were obtained from the Traditional Chinese Medicine Database and Analysis Platform. Targets of the active constituents were predicted using the similarity ensemble approach search server and Swiss Target Prediction tool. YQHX-targeted key TFs that transcribed the DEGs were screened out. Then, the effect of YQHX on the bleomycin-induced pulmonary fibrosis mouse model was studied. Finally, one of the predicted TFs, STAT3, was selected to validate the prediction accuracy. RESULTS: Seven, two, and five compounds were identified in the GR, CR, and NR extracts, respectively. YQHX and its constituents-GR, CR and NR-inhibited the expression of fibrotic markers, including α -SMA and fibronectin, indicating that YQHX inhibited TGF-ß1-induced myofibroblast activation. RNA-sequencing identified 291 genes that were up-regulated in the TGF-ß1 group but down-regulated after YQHX treatment. In total, 55 key TFs that transcribed YQHX-regulated targets were predicted. A regulatory network of 24 active ingredients and 232 corresponding targets for YQHX was established. Among YQHX's predicted targets, 20 were TFs. On overlapping YQHX-targeted TFs and DEGs' key TFs, six key TFs, including HIF1A, STAT6, STAT3, PPARA, DDIT3 and AR, were identified as the targets of YQHX. Additionally, YQHX alleviated bleomycin-induced pulmonary fibrosis in a mouse model by inhibiting the phosphorylation of STAT3 in the lungs of pulmonary fibrosis mice. CONCLUSIONS: This study provides pharmacological support for the use of YQHX in the treatment of IPF. The potential mechanism of action of YQHX is speculated to involve the modulation of core TFs and inhibition of pathogenetic gene expressions in IPF.

Elucidation of the anti-inflammatory mechanism of Er Miao San by integrative approach of network pharmacology and experimental verification.

Traditional Chinese medicine (TCM) has been long time used in China and gains ever-increasing worldwide acceptance. Er Miao San (EMS), a TCM formula, has been extensively used to treat inflammatory diseases, while its bioactive components and therapeutic mechanisms remain unclear. In this study, we conducted an integrative approach of network pharmacology and experimental study to elucidate the underlying mechanisms of EMS in treating human rheumatoid arthritis (RA) and other inflammatory conditions. Quercetin, wogonin and rutaecarpine were probably the main active compounds of EMS in RA treatment as they affected the most RA-related targets, and TNF-α, IL-6 and IL-1ß were considered to be the core target proteins. The main compounds in EMS bound to these core proteins, which was further confirmed by molecular docking and bio-layer interferometry (BLI) analysis. Moreover, the potential molecular mechanisms of EMS predicted from network pharmacology analysis, were validated in vivo and in vitro experiments. EMS was found to inhibit the production of NO, TNF-α and IL-6 in lipopolysaccharide (LPS)-stimulated RAW264.7 cells; reduce xylene-induced mouse ear edema; and decrease the incidence of carrageenan-induced rat paw edema. The carrageenan-induced up-regulation of TNF-α, IL-6 and IL-1ß mRNA expression in rat paws was down-regulated by EMS, consistent with the network pharmacology results. This study provides evidence that EMS plays a critical role in anti-inflammation via suppressing inflammatory cytokines, indicating that EMS is a candidate herbal drug for further investigation in treating inflammatory and arthritic conditions.

[Effect and mechanism of moxibustion on oxidative stress injury in rats with Parkinson's disease by activating Nrf2/ARE pathway].

OBJECTIVE: To observe the effect of moxibustion on oxidative stress injury of nigrostriatal system in rats with Parkinson's disease (PD) based on nuclear factor erythroid 2-related factor (Nrf2)/antioxidant response element (ARE) pathway, and to explore its mechanism. METHODS: A total of 48 SD rats were randomized into a blank group, a sham-operation group, a model group and a moxibustion group, 12 rats in each group. Unilateral two-point injection with 6-hydroxydopamine (6-OHDA) was adopted in the model group and the moxibustion group to establish the PD model; the operation manipulation in the sham-operation group was the same as the model group and the moxibustion group, and the same volume of 0.9% sodium chloride solutions was given by unilateral two-point injection. Moxibustion was adopted at "Baihui" (GV 20) and "Sishencong" (EX-HN 1) in the moxibustion group for 20 min, once a day, 6 times a week for 6 weeks. No intervention was given in the other 3 groups. Morphology of right mesencephalon substantia nigra was observed by HE staining, the expression of tyrosine hydroxylase (TH) in right mesencephalon substantia nigra was detected by immunohistochemistry method, the expression of reactive oxygen species (ROS), malondialdehyde (MDA), glutathione (GSH), and glutathione peroxidase (GSH-Px) in corpus striatum was detected by colorimetry method, and the expression of Nrf2 and heme oxygenase-1 (HO-1) proteins was detected by Western blot in the 4 groups. RESULTS: Clear tissue structure and complete dopaminergic neurons of right mesencephalon substantia nigra were observed in the blank group and the sham-operation group; unclear tissue structure, decreased and swelling dopaminergic neurons were observed in the model group; compared with the model group, more neurons were observed and the swelling of cyton was reduced in the moxibustion group. Compared with the sham-operation group, the expression of TH in right mesencephalon substantia nigra was decreased in the model group (P<0.01); compared with the model group, the expression of TH in right mesencephalon substantia nigra was increased in the moxibustion group (P<0.05). Compared with the sham-operation group, the expression of ROS, MDA was increased (P<0.01), the expression of GSH, GSH-Px, Nrf2 and HO-1 was decreased in the model group (P<0.01, P<0.05); compared with the model group, the expression of ROS, MDA was decreased (P<0.05, P<0.01), the expression of GSH, GSH-Px, Nrf2 and HO-1 was increased in the moxibustion group (P<0.05, P<0.01). CONCLUSION: Moxibustion can alleviate oxidative stress injury of nigrostriatal system in rats with Parkinson's disease by activating the Nrf2/ARE pathway, and protect the dopamine neurons.

Moxibustion Exerts a Neuroprotective Effect through Antiferroptosis in Parkinson's Disease.

The objective of this study was to explore the neuroprotective effect of moxibustion on rats with Parkinson's disease (PD) and its mechanism. A Parkinson's disease model was established in rats using a two-point stereotactic 6-hydroxydopamine injection in the right substantia nigra (SN) and ventral tegmental area. The rats received moxibustion at the Baihui (GV20) and Sishencong (EX-HN1) acupoints for 20 minutes, six times a week, for 6 weeks. The right SN tissue was histologically and immunohistochemically examined. Differentially expressed genes (DEGs) were identified through RNA sequencing. In addition, the levels of tyrosine hydroxylase (TH), glutathione peroxidase 4 (GPX4), and ferritin heavy chain 1 (FTH1) in SN were measured. In comparison to the model group, the moxibustion group showed a significantly greater TH immunoreactivity and a higher behavioural score. In particular, moxibustion led to an increase in the number and morphological stability of SN neural cells. The functional pathway analysis showed that DEGs are closely related to the ferroptosis pathway. GPX4 and FTH1 in the SN were significantly overexpressed in the moxibustion-treated rats with PD. Moxibustion can effectively reduce the death of SN neurons, decrease the occurrence of ferroptosis, and increase the TH activity to protect the neurons in rats with PD. The protective mechanism may be associated with suppression of the ferroptosis.

Identification and Characterization of miRNAs in Self-Rooted and Grafted Malus Reveals Critical Networks Associated with Flowering.

Grafting can improve the agricultural traits of crop plants, especially fruit trees. However, the regulatory networks and differentially expressed microRNAs (miRNAs) related to grafting in apple remain unclear. Herein, we conducted high-throughput sequencing and identified differentially expressed miRNAs among self-rooted Fuji, self-rooted M9, and grafted Fuji/M9. We analyzed the flowering rate, leaf morphology, and nutrient and carbohydrate contents in the three materials. The flowering rate, element and carbohydrate contents, and expression levels of flowering genes were higher in Fuji/M9 than in Fuji. We detected 206 known miRNAs and 976 novel miRNAs in the three materials, and identified those that were up- or downregulated in response to grafting. miR156 was most abundant in Fuji, followed by Fuji/M9, and then self-rooted M9, while miR172 was most abundant in M9, followed by Fuji/M9, and then Fuji. These expression patterns suggest that that these miRNAs were related to grafting. A Gene Ontology (GO) analysis showed that the differentially expressed miRNAs controlled genes involved in various biological processes, including cellular biosynthesis and metabolism. The expression of differentially expressed miRNAs and flowering-related genes was verified by qRT-PCR. Altogether, this comprehensive analysis of miRNAs related to grafting provides valuable information for breeding and grafting of apple and other fruit trees.

[The effect of G protein regulator on pollen germination and [Ca2+]i variation in Pyrus serotina Rehd. pollen].

The effects of the cholera toxin (CTX) and pertussis toxin (PTX), which can activate and antagonize respectively the heterotrimeric G protein, on pollen germination, pollen tube growth and the dynamic of cytosolic free calcium concentration ([Ca(2+)]i) in pear pollen were investigated using Laser Confocal Scanning Microscope (LCSM). The results show that CTX could stimulate pollen germination and tube growth while PTX had the opposite effect. CTX and PTX had marked influence on the dynamic of pollen [Ca(2+)]i. The CTX treatment had no significant effect on the changes in pollen [Ca(2+)]i during pollen germination, but induced specific signaling of "calcium transient" in pollen. Treatment with PTX caused decline of pollen [Ca(2+)]i in the first 18 min after treatment. These data suggested that the regulation of pollen germination and tube growth in Pyrus serotina may involve in heterotrimeric G protein, which can stimulate specific change of pollen [Ca(2+)]i.