Forsythiaside A attenuates lipopolysaccharide-induced mouse mastitis by activating autophagy and regulating gut microbiota and metabolism.

Mastitis is an inflammatory disease of the mammary gland with a high incidence in lactating animals, significantly impacting their health and breastfeeding. Moreover, mastitis adversely affects milk quality and yield, resulting in substantial economic losses for the dairy farming industry. Forsythiaside A (FTA), a phenylethanol glycoside analog extracted from Forsythia, exhibits notable anti-inflammatory and antioxidant properties. However, its protective effects and specific mechanisms against mastitis remain unclear. In this study, a lipopolysaccharide (LPS)-induced mouse mastitis model was used to investigate the protective effect of FTA on LPS-induced mastitis and its potential mechanism using histological assays, Western blot, qRT-PCR, FITC-albumin permeability test, 16s rRNA gene sequencing analysis and non-targeted metabolomics assays to investigate the protective effect of FTA on LPS-induced mastitis model and its potential mechanism. The results demonstrated that FTA significantly mitigated LPS-induced mouse mastitis by reducing inflammation and apoptosis levels, modulating the PI3K/AKT/mTOR signaling pathways, inducing autophagy, and enhancing antioxidant capacity and the expression of tight junction proteins. Furthermore, FTA increased the abundance of beneficial microbiota while decreasing the levels of harmful microbiota in mice, thus counteracting the gut microbiota disruption induced by LPS stimulation. Intestinal metabolomics analysis revealed that FTA primarily regulated LPS-induced metabolite alterations through key metabolic pathways, such as tryptophan metabolism. This study confirms the anti-inflammatory and antioxidant effects of FTA on mouse mastitis, which are associated with key metabolic pathways, including the restoration of gut microbiota balance and the regulation of tryptophan metabolism. These findings provide a novel foundation for the treatment and prevention of mammalian mastitis using FTA.

Forsythiaside A suppresses renal fibrosis and partial epithelial-mesenchymal transition by targeting THBS1 through the PI3K/AKT signaling pathway.

Renal fibrosis is a key feature of chronic kidney disease (CKD) progression, whereas no proven effective anti-fibrotic treatments. Forsythiaside A (FTA), derived from Forsythia suspense, has been found to possess nephroprotective properties. However, there is limited research on its anti-fibrotic effects, and its mechanism of action remains unknown. This study aimed to investigate the suppressive effects of FTA on renal fibrosis and explore the underlying mechanisms. In vitro, we established a HK2 cell model induced by transforming growth factor ß1 (TGF-ß1), and in vivo, we used a mice model induced by unilateral ureteral obstruction (UUO). CCK-8 assay, qRT-PCR, Western blotting, immunofluorescence, flow cytometry, histological staining, immunohistochemistry, TUNEL assay, RNA transcriptome sequencing, and molecular docking were performed. The results showed that FTA (40 µM or 80 µM) treatment improved cell viability and suppressed TGF-ß1-induced fibrotic changes and partial epithelial-mesenchymal transition (EMT). Furthermore, FTA treatment reversed the activation of the PI3K/AKT signaling pathway, and THBS1 was identified as the target gene. We found that THBS1 knockdown suppressed the activation of the PI3K/AKT signaling pathway and reduced the fibrosis and partial EMT-related protein level. Conversely, THBS1 overexpression activated the PI3K/AKT signaling pathway and exacerbated renal fibrosis and partial EMT. In vivo, mice were administered FTA (30 or 60 mg/kg) for 2 weeks, and the results demonstrated that FTA administration significantly mitigated tubular injury, tubulointerstitial fibrosis, partial EMT, and apoptosis. In conclusion, FTA inhibited renal fibrosis and partial EMT by targeting THBS1 and inhibiting activation of the PI3K/AKT pathway.

Forsythiaside A attenuates mastitis via PINK1/Parkin-mediated mitophagy.

BACKGROUND: Bovine mastitis is the most common animal production disease in the global dairy industry, which affects the health of dairy cows. When bovine mastitis occurs, the mitochondrial metabolism of breast tissue increases, and the relationship between inflammation and mitophagy has become a hot topic for many scholars. The abuse of antibiotics leads to the increase of resistance to bovine mastitis. FTA is one of the main effective components of Forsythia suspensa, which has anti-inflammatory, anti-infection, anti-oxidation and anti-virus pharmacological effects, and has broad application prospects in the prevention and treatment of bovine mastitis. However, the relationship between the anti-inflammatory effects of FTA and mitophagy is still unclear. PURPOSE: This study mainly explores the anti-inflammatory effect of FTA in bovine mastitis and the relationship between mitophagy. METHODS: MAC-T cells and wild-type mice were used to simulate the in vitro and in vivo response of mastitis. After the pretreatment with FTA, CsA inhibitors and siPINK1 were used to interfere with mitophagy, and the mitochondrial function impairment and the expression of inflammatory factors were detected. RESULTS: It was found that pre-treatment with FTA significantly reduced LPS induced inflammatory response and mitochondrial damage, while promoting the expression of mitophagy related factors. However, after inhibiting mitophagy, the anti-inflammatory effect of FTA was inhibited. CONCLUSION: This study is the first to suggest the relationship between the anti-inflammatory effect of FTA and mitophagy. PINK1/Parkin-mediated mitophagy is one of the ways that FTA protects MAC-T cells from LPS-induced inflammatory damage.

Forsythiaside A exhibits anti-migration and anti-inflammation effects in rheumatoid arthritis in vitro model.

BACKGROUND: Rheumatoid arthritis (RA) is a kind of systemic autoimmune disease, and the joint inflammation and cartilage destruction are the major features. Some traditional Chinese medicine have been discovered to exhibit regulatory roles in the treatment of RA. Forsythiaside A (FA) as an active ingredient isolated from forsythia suspensa has been discovered to participate into the regulation of some diseases through improving inflammation. However, the regulatory effects of FA on the progression of RA keep indistinct. METHODS: IL-1ß treatment (10 ng/mL) in MH7A cells was built to mimic RA in vitro (cell) model. The cell viability was examined through CCK-8 assay. The cell proliferation was detected through Edu assay. The levels of TNF-α, IL-6, and IL-8 were evaluated through ELISA. The protein expressions were measured through western blot. The cell apoptosis was assessed through flow cytometry. The cell migration and invasion abilities were tested through Transwell assay. RESULTS: In this study, it was revealed that the cell proliferation was strengthened after IL-1ß treatment (p < .001), but this effect was reversed after FA treatment in a dose-increasing manner (p < .05). Furthermore, FA suppressed inflammation in IL-1ß-triggered MH7A cells through attenuating the levels of TNF-α, IL-6, and IL-8 (p < .05). The cell apoptosis was lessened after IL-1ß treatment (p < .001), but this effect was rescued after FA treatment (p < .05). Besides, the cell migration and invasion abilities were both increased after IL-1ß treatment (p < .001), but these changes were offset after FA treatment (p < .05). Eventually, FA retarded the JAK/STAT pathway through reducing p-JAK/JAK and p-STAT/STAT levels (p < .01). CONCLUSION: Our study manifested that FA exhibited anti-migration and anti-inflammation effects in RA in vitro model (IL-1ß-triggered MH7A cells) through regulating the JAK/STAT pathway. This work hinted that FA can be an effective drug for RA treatment.

Forsythiaside A Activates AMP-Activated Protein Kinase and Regulates Oxidative Stress via Nrf2 Signaling.

Forsythiaside A (FA) is an active constituent isolated from Forsythia suspensa, a beneficial herb used in traditional medicine known for its antioxidant and anti-inflammatory properties. Although various studies have suggested that FA has the protective effects, its impacts on arachidonic acid (AA) plus iron in vitro models and carbon tetrachloride (CCl4)-induced mouse liver damage in vivo have not been explored. In this study, HepG2 cells were subjected to AA + iron treatment to induce apoptosis and mitochondrial impairment and determine the molecular mechanisms. FA exhibited protective effects by inhibiting cell damage and reactive oxygen species (ROS) production induced by AA + iron, as assessed via immunoblot and flow cytometry analyses. Further molecular investigations revealed that FA resulted in the activation of extracellular-signal-related protein kinase (ERK), which subsequently triggered the activation of AMP-activated protein kinase (AMPK), a critical regulator of cellular oxidative stress. Additionally, FA modulated the nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathway, which is a significant antioxidant transcription factor regulated by the AMPK pathway. For in vivo studies, mice were orally administered FA and then subjected to induction of CCl4-based hepatotoxicity. The protective effect of FA was confirmed via blood biochemistry and immunohistochemical analyses. In conclusion, our findings demonstrated the protective effects of FA against oxidative stress both in vitro and in vivo, thus indicating that FA is a potential candidate for liver protection. Our study sheds light on the mechanistic pathways involved in the antioxidant effects of FA, highlighting the hepatoprotective potential of naturally occurring compounds in traditional herbs, such as FA.

Forsythiaside A alleviates acute lung injury by inhibiting inflammation and epithelial barrier damages in lung and colon through PPAR-γ/RXR-α complex.

INTRODUCTION: Acute lung injury (ALI) is a lung disease characterized by inflammation and still requires further drug development. Forsythiaside A as the active compound of Forsythiae Fructus has the therapeutic potential for ALI. OBJECTIVE: To investigate the mechanism of forsythiaside A in treating ALI through PPAR-γ and its conjugate RXR-α based on gut-lung axis. METHODS: This study constructed in vitro and in vivo injury models using LPS and TNF-α. Forsythiaside A was used for the drug treatment, and RXR-α inhibitor UVI3003 was used to interfere with PPAR-γ/RXR-α complexes in the cells. HE staining was used for histopathological examination. Serum endotoxin contents were determined using limulus lysate kit. IHC staining and Western blot were conducted to assess the protein expressions. ELISA was applied to examine the content of pro-inflammatory cytokines in the cell supernatants. The protein interactions were analyzed via CO-IP. RESULTS: In vivo results showed that forsythiaside A regulated PPAR-γ/RXR-α and inhibited TLR4/MAPK/NF-κB and MLCK/MLC2 signal pathways, thus inhibiting inflammation and epithelial barrier damages of lung and colon in ALI mice induced by intratracheal LPS. PPAR-γ/RXR-α were promoted by forsythiaside A in lungs, whereas inhibited by forsythiaside A in colons. Additionally, in vitro results showed that forsythiaside A suppressed inflammation and epithelial barrier damages in macrophages and lung/colon epithelial cells, by manipulating PPAR-γ/RXR-α to suppress the LPS- and TNF-α-induced activation of TLR4/MAPK/NF-κB and NF-κB/MLCK/MLC2 signal pathways. Moreover, further mechanism study indicated that forsythiaside A showed a cell-specific regulatory effect on PPAR-γ/RXR-α complex. Specifically, the PPAR-γ/RXR-α protein interactions were promoted by forsythiaside A in LPS-induced macrophages RAW264.7 and TNF-α-induced lung epithelial cells A549, but inhibited by forsythiaside A in TNF-α-induced colon epithelial cells SW620. CONCLUSION: In the treatment of ALI, Forsythiaside A inhibited inflammation and epithelial barrier damages of lung and colon through its regulation on PPAR-γ/RXR-α complex.

The protective effect of forsythiaside A on 3,5-diethoxycarbonyl-1,4-dihydrocollidine-induced cholestatic liver injury in mice: Based on targeted metabolomics and molecular biology technology.

Cholestasis is a disorder of bile secretion and excretion caused by a variety of etiologies. At present, there is a lack of functional foods or drugs that can be used for intervention. Forsythiaside A (FTA) is a natural phytochemical component isolated from the medicinal plant Forsythia suspensa (Thunb.) Vahl, which has a significant hepatoprotective effect. In this study, we investigated whether FTA could alleviate liver injury induced by cholestasis. In vitro, FTA reversed the decrease in viability of human intrahepatic bile duct epithelial cells, the decrease in antioxidant enzymes (SOD1, CAT and GSH-Px), and cell apoptosis induced by lithocholic acid. In vivo, FTA protected mice from 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC)-induced liver injury, abnormal serum biochemical indexes, abnormal bile duct hyperplasia, and inflammatory infiltration. Furthermore, FTA treatment alleviated liver fibrosis by inhibiting collagen deposition and HSC activation. The metabonomic results showed that DDC-induced bile acid disorders in the liver and serum were reversed after FTA treatment, which may benefit from the activation of the FXR/BSEP axis. In addition, FTA treatment increased the levels of antioxidant enzymes in the serum and liver. Meanwhile, FTA treatment inhibited ROS and MDA levels and cleaved caspase 3 protein expression, thereby reducing DDC-induced hepatic oxidative stress and apoptosis. Further studies showed that the antioxidant effects of FTA were dependent on the activation of the BRG1/NRF2/HO-1 axis. In a word, FTA has a significant hepatoprotective effect on cholestatic liver injury, and can be further developed as a functional food or drug to prevent and treat cholestatic liver injury.

Forsythiaside A Alleviates Lipopolysaccharide-Induced Acute Liver Injury through Inhibiting Endoplasmic Reticulum Stress and NLRP3 Inflammasome Activation.

The liver is the primary site of inflammation caused by bacterial endotoxins in sepsis, and septic acute liver injury (SALI) is usually associated with poor outcomes in sepsis. Forsythiaside A (FTA), an active constituent of Forsythia suspensa, has been reported to have anti-inflammatory properties, antioxidant properties, and protective properties against neuroinflammation, sepsis, and edema. Therefore, the purpose of the present study was to examine FTA's potential effects on lipopolysaccharide (LPS)-induced SALI in mice. Our results indicated that pretreatment with FTA significantly attenuated aspartate aminotransferase (AST) and aminoleucine transferase (ALT) levels in plasma, ameliorated histopathological damage, inhibited hepatocyte apoptosis, diminished the expression of tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, and IL-6 in the liver from mice exposed to LPS. Furthermore, our data showed that the administration of LPS resulted in robust endoplasmic reticulum (ER) stress response, as evidenced by glucose-regulated protein 78 (GRP78) upregulation, phosphorylated-protein kinase R-like ER kinase (p-PERK) activation, elF2α phosphorylation, and activating transcription factor 4 (ATF4) and CHOP overexpression in the liver. This, in turn, led to nucleotide-binding oligomerization domain-like receptor pyrin domain containing 3 (NLRP3) inflammasome activation, including the cleavage of caspase-1, secretion of IL-1ß, and pyroptotic cell death in the liver specimens. Importantly, the ER stress response induced by the LPS challenge was blocked by FTA administration. Correspondingly, NLRP3 inflammasome activation was significantly ameliorated by the pretreatment with FTA. Thus, we demonstrated that FTA pretreatment could protect mice from LPS-induced SALI, and its protective effects were possibly mediated by inhibiting ER stress response and subsequent NLRP3 inflammasome activation.

Forsythiaside A prevents zymosan A-induced cell migration in neutrophil-differentiated HL-60 cells via PD-1/PD-L1 pathway.

Neutrophils, which account for more than 80% of leukocyte, play an important role in resolution of inflammation. Immune checkpoint molecules could be potential biomarkers in immunosuppression. Forsythiaside A (FTA), a main constituent of Forsythia suspensa (Thunb.) Vahl, provides a very significant anti-inflammatory activity. Here we defined the immunological mechanisms of FTA by taking programmed cell death-1 (PD-1)/programmed cell death-Ligand 1 (PD-L1) pathway into consideration. FTA could inhibited cell migration in HL-60-derived neutrophils in vitro, and this action appeared to be mediated via PD-1/PD-L1 depended JNK and p38 MAPK pathways. In vivo, FTA prevented PD-L1+ neutrophils infiltration and reduced the levels of tumor necrosis factor alpha (TNF-α), interleukin-6 (IL-6), monocyte chemoattractant protein-1 (MCP-1) and interferon-gamma (IFN-γ) after zymosan A-induced peritonitis. PD-1/PD-L1 inhibitor could abolish the suppression of FTA. The expression of inflammatory cytokines and chemokines were positively correlated with PD-L1. Molecular docking showed that FTA could bind to PD-L1. Taken together, FTA might prevent neutrophils infiltration to exert inflammation resolution through PD-1/PD-L1 pathway.

Forsythiaside A ameliorates sepsis-induced acute kidney injury via anti-inflammation and antiapoptotic effects by regulating endoplasmic reticulum stress.

ETHNOPHARMACOLOGICAL RELEVANCE: Sepsis is a systemic inflammatory response syndrome caused by an infection in the body, and accompanying acute kidney injury (AKI) is a common complication of sepsis. It is associated with increased mortality and morbidity. Forsythia Fructus, the dried fruit of Forsythia suspensa (Thunb.) Vahl, is a commonly used traditional Chinese medicine. AIMS OF THE STUDY: This study aimed to elucidate the protective effect of Forsythiaside A (FTA) on sepsis-induced AKI by downregulating inflammatory and apoptotic responses, and exploring its underlying mechanism. METHODS: Septic AKI was induced through intraperitoneal injection of LPS (10 mg/kg) using male C57BL/6 mice and pretreated with FTA or control saline. First, we assessed the degree of renal injury by creatinine, blood urea nitrogen measurement, and HE staining of renal tissue; secondly, the inflammation and apoptosis were measured byELISA, qPCR, and TUNEL immunofluorescence; finally, the mechanism was explored by computer molecular docking and Western blot. RESULTS: Our data showed that FTA markedly attenuated pathological kidney injuries, alleviated the elevation of serum BUN and Creatinine, suggesting the renal protective effect of FTA. Notably, FTA significantly inhibited the renal expression of proinflammatory cytokine IL-1ß, IL-6, and TNF-α both at protein and mRNA levels and attenuated cell apoptosis in the kidney, as measured by caspase-3 immunoblot and TUNEL assay, indicating its anti-Inflammation and antiapoptotic properties. Mechanistically, administration of LPS resulted in robust endoplasmic reticulum (ER) stress responses in the kidney, evidenced by glucose-regulated protein 78(GRP78) upregulation, protein kinase RNA-like endoplasmic reticulum kinase (PERK) activation, eukaryotic initiation factor 2 alpha (elF2α) phosphorylation and C/EBP homologous protein (CHOP) overexpression, which could be significantly blocked by FTA pretreatment. Dynamic simulation and molecular docking were performed to provide further insight. CONCLUSIONS: Collectively, our data suggest that FTA ameliorates sepsis-induced acute kidney injury via its anti-inflammation and antiapoptotic properties by regulating PERK signaling dependent ER stress responses.

CD44-Targeting Drug Delivery System of Exosomes Loading Forsythiaside A Combats Liver Fibrosis via Regulating NLRP3-Mediated Pyroptosis.

Liver fibrosis is a progressive pathological process induced by various stimuli and may progress to liver cirrhosis and cancer. Forsythiaside A (FA) is an active ingredient extracted from traditional Chinese medicine Forsythiae Fructus and has prominent hepatoprotective activities. However, the unsatisfactory pharmacokinetic properties restrict its clinical application. In this study, the nanocarrier of CD44-specific ligand Hyaluronic acid (HA)-modified milk-derived exosomes (mExo) encapsulated with FA (HA-mExo-FA) is developed. As a result, HA modification could deliver drug-loaded exosomes to the target cells and form a specific ligand-receptor interaction with CD44, thus improving the anti-liver fibrosis effect of FA. In vitro findings indicate that HA-mExo-FA could inhibit TGF-ß1-induced LX2 cell proliferation, reduce α-SMA and collagen gene and protein levels, and promote the apoptosis of activated LX2 cells. In vivo results demonstrate that HA-mExo-FA could improve liver morphology and function changes in zebrafish larvae. The anti-liver fibrosis mechanism of HA-mExo-FA may be attributed to the inhibition of NLRP3-mediated pyroptosis. In addition, the effect of HA-mExo-FA on TAA-induced increase in NLRP3 production is attenuated by NLRP3 inhibitor MCC950. Collectively, this study demonstrates the promising application of HA-mExo-FA in drug delivery with high specificity and provides a powerful and novel delivery platform for liver fibrosis therapy.

Transcriptomic profiling of lipopolysaccharide-challenged bovine mammary epithelial cells treated with forsythoside A.

Mastitis is usually caused by a variety of pathogenic bacteria that seriously impact the health and milk-production ability of dairy cows, with consequent, economically detrimental effects on the dairy industry. Forsythoside A (FTA), isolated from the fruit and leaves of Forsythia suspensa (Thunb.) Vahl (Oleaceae), has been reported to have significant antioxidant, anti-inflammatory, and antibacterial effects. However, it is not clear whether FTA exerts a protective effect against lipopolysaccharide (LPS)-induced bovine mastitis and its potential gene signature. In this study, high-throughput sequencing technology was performed to analyze the differences between the mRNA and enrichment pathway of bovine mammary epithelial cells of the control, LPS, and LPS + FTA groups. The results showed that there were 139 differentially expressed genes (DEGs) (p-value < 0.05, |log2FoldChange| > 1, FPKM > 1) in the LPS group compared with the control group, including 121 up-regulated genes and 18 down-regulated genes, which were mainly enriched in the cellular response to lipopolysaccharide, cytokine activity, protein binding, and IL-17 signaling pathway based on Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis, respectively. Compared with the control group and LPS + FTA group, there were 349 DEGs, including 322 up-regulated genes and 27 down-regulated genes. They were mainly enriched in protein localization to organelles, centrosomes, binding, and the IL-17 signaling pathway, based on GO and KEGG analysis. Compared to the LPS group, the LPS + FTA group had 272 DEGs, including 259 up-regulated genes and 13 down-regulated genes, which were mainly enriched in RNA processing, IL-6 receptor binding, and the lysosome pathway, based on GO and KEGG analyses. It can be seen that LPS stimulation induced the expression of inflammation-related genes, IL-17 and IL-6, whereas FTA treatment promoted the expression of the spliceosome-, lysosome-, and oxidative stress-related genes HSP70, HSPA8, and PARP2. The study utilized RNA-sequencing analysis of FTA against LPS-challenged bovine mammary epithelial cells to explore key mRNA findings that may be strongly associated with inflammation and oxidative stress, and provides a theoretical reference for further elucidation of molecular mechanisms of bovine mastitis and therapeutic effects of FTA against bovine mastitis.

[Effect of forsythiaside A against CCl_4-induced liver fibrosis in mice and its mechanism].

This study aims to investigate the efficacy of forsythiaside A(FTA) against CCl_4-induced liver fibrosis and the mechanism. Specifically, activities of serum alanine/aspartate aminotransferase(ALT/AST) and hydroxyproline(HYP) level in liver were detected, and pathological morphology of liver was observed based on hematoxylin-eosin(HE) staining, Masson's trichrome staining, and Sirius red staining of liver. On this basis, the effect of FTA on liver fibrosis was evaluated. The mRNA expression of actin alpha 2/α-smooth muscle actin(Acta2/α-SMA), transforming growth factor ß(Tgfß), collagen Ⅰ alpha 1(Col1 a1), and collagen Ⅲ alpha 1(Col3 a1) in liver tissue and hepatic stellate cells(HSC) was determined by qPCR, and the protein expression of α-SMA in liver tissue and HSC was measured by Western blot to assess the inhibition of FTA on HSC activation. The protein expression of α-SMA, vi-mentin(Vim), vascular endothelial cadherin(Ve-cadherin), and platelet endothelial cell adhesion molecule-1(PECAM-1/CD31) was measured by Western blot to evaluate the reverse of endothelial-mesenchymal transition(EMT) by FTA. The efficacy of FTA in relieving CCl_4-induced liver fibrosis was evidenced by the alleviation of hepatocyte necrosis, liver inflammation, and hepatic collagen deposition. FTA decreased the mRNA expression of Acta2, Tgfß, Col1 a1, and Col3 a1 and protein expression of α-SMA both in vivo and in vitro. FTA reversed the increase of α-SMA and Vim and the decrease of CD31 and Ve-cadherin in livers from mice treated with CCl_4. Therefore, FTA alleviated CCl_4-induced liver fibrosis in mice via suppressing HSC activation and reversing EMT.

Forsythiaside A improves Influenza A virus infection through TLR7 signaling pathway in the lungs of mice.

BACKGROUND: Influenza A virus infection due to drug resistance and side effects of the conventional antiviral drugs yet remains a serious public health threat for humans and animals. Forsythiaside A is an effective ingredient isolated from the Chinese herbal medicine forsythia. It has various pharmacological effects and has a good therapeutic effect against a variety of infectious diseases. This study aimed to further explore the immunological mechanism of Forsythiaside A in the treatment of influenza virus-infected mice and its effect on the Toll-like receptor 7 (TLR7) signaling pathway in the lungs of these mice. METHODS: C57/BL6J mice and TLR7-/- mice were infected with the FM1 strains (H1N1 and A/FM/1/4) of the Influenza A virus. Each group of experimental mice were divided into the mock, virus, oseltamivir, and Forsythiaside A groups. Weight change, lung index change, and the mRNA and protein expression levels of key factors in the TLR7 signaling pathway were detected. Flow cytometry was used to detect the changes in the Th1/Th2 and Th17/Treg ratios. RESULTS: After infection with the Influenza A virus, the weight loss of C57/BL6J mice treated with forsythoside A and oseltamivir decreased, and the pathological tissue sections showed that the inflammatory damage was reduced. The expression levels of the key factors, TLR7, myeloid differentiation factor 88(Myd88), and nuclear factor-kappa B (NF-κB) in the TLR7 signaling pathway were significantly reduced. Flow cytometry showed that Th1/Th2 and Th17/Treg ratios decreased after Forsythiaside A treatment. In the TLR7-/- mice, there was no significant change after Forsythiaside A treatment in the virus group. CONCLUSIONS: Forsythiaside A affects the TLR7 signaling pathway in mouse lung immune cells and reduces the inflammatory response caused by the Influenza A virus FM1 strain in mouse lungs.

Forsythiaside A alleviated carbon tetrachloride-induced liver fibrosis by modulating gut microbiota composition to increase short-chain fatty acids and restoring bile acids metabolism disorder.

Liver fibrosis is a chronic and progressive disease with complex pathogenesis related to bile acids (BAs) and gut microbiota. Forsythiaside A (FTA), isolated from the traditional Chinese medicine Forsythiae Fructus (Lian Qiao), is a natural hepatoprotective agent. The purpose of this study was to investigate the protective effect of FTA on carbon tetrachloride (CCl4)-induced liver fibrosis in mice. Liver fibrosis was induced in mice by intraperitoneal injection of 2 mL/kg CCl4 three times a week for 4 weeks. FTA attenuated CCl4-induced liver fibrosis in mice, which was proved by the results of Masson and Sirius red staining, liver hydroxyproline, hyaluronic acid, laminin, type III procollagen, and type IV collagen assays. FTA inhibited hepatic stellate cell activation, and reduced hepatic inflammation and oxidative stress in mice treated with CCl4. What's more, FTA ameliorated CCl4-induced gut dysbiosis, maintained intestinal barrier function, increased the production of short-chain fatty acids (SCFAs), and improved endotoxemia, as manifested by decreased serum lipopolysaccharide levels and increased expression of ileal tight junction proteins. Besides, FTA can modulate the genes related to bile acid metabolism to alter the distribution of fecal BAs in fibrotic mice. In a word, FTA can improve liver fibrosis by inhibiting inflammation and oxidative stress, regulating gut microbiota and BA metabolism, and increasing the content of SCFAs. The results of this study provided an important reference for the study on the mechanisms by which natural products prevent liver fibrosis.

Forsythiaside A alleviates methotrexate-induced intestinal mucositis in rats by modulating the NLRP3 signaling pathways.

Most chemotherapeutic drugs can kill the tumor cells, but also cause a vast damage to body, such as intestinal mucositis (IM). The present study was design to find out the effect of Forsythiaside A (FTA) on chemotherapeutic-induced IM in rats. Briefly, for 3 consecutive days, male Sprague-Dawley rats were treated with 7 mg / kg methotrexate (MTX) to establish IM and simultaneously administered with 40 or 80 mg / kg FTA for 7 days. Our results showed that the final body weight and daily food intake were increased, and the disease activity index was reduced in the MTX group after FTA treatment. The MTX group showed the pathological alterations like the inflammatory cells infiltration, the mucosal layer destruction, glands expansion, intestinal villi structure disorder and goblet cells reduction, while we found that 80 mg / kg FTA treatment displayed evident reversal effects. ELISA further suggested that TNF-α, IL-1ß and IL-18 levels in serum in MTX-induced rats were reduced after 80 mg / kg FTA treatment. Moreover, FTA decreased the number of leukocytes, neutrophils and lymphocytes in peripheral blood. Western blot and immunofluorescence results indicated that the expression levels of NLRP3, cleaved caspase 1, cleaved IL-1ß and CD68 positive rate were down-regulated in MTX-induced rats after 80 mg / kg FTA intervention. The findings of the current study suggested that FTA effectively inhibited MTX-induced IM in rats by attenuating the activation of the NLRP3 signaling pathways.

Protective effect of forsythiaside A on acute lung injury in septic rats / 中华危重病急救医学

Objective:To observe the protective effect of forsythiaside A on acute lung injury (ALI) in septic rats.Methods:Male Sprague-Dawley (SD) rats were randomly divided into normal control group, sham operation group, sepsis model group, and forsythiaside A intervention group, with 10 rats in each group. The rats in the normal control group did not receive any intervention; the rats in the sham operation group only underwent abdominal surgery; and those in the model group and forsythiaside A intervention group received cecal ligation and puncture (CLP) to establish the sepsis rat model. The rats in the forsythiaside A intervention group were given 75 mL/kg of forsythiaside A within 0.5 hour after operation, and repeated after 6 hours. The rats in the sham operation group and model group were given the same amount of normal saline at the same time points. The lung tissues were collected for pathological examination 12 hours after operation. The lung homogenate was prepared, and enzyme-linked immunosorbent assay (ELISA) was used to detect tumor necrosis factor-α (TNF-α), interleukins (IL-1β, IL-6). The activity of superoxide dismutase (SOD) was detected by xanthine oxidase method, and the content of malonaldehyde (MDA) was detected by colorimetry. The expression of nuclear factor-κB p65 (NF-κB p65) was detected by Western blotting.Results:There was no significant pathological change of lung tissue in both normal control group and sham operation group, and there was no significant difference in each parameter between the two groups. The rats in the model group had interstitial infiltration of inflammatory cells, alveolar structure destruction, alveolar septum thicken, extensive alveolar hemorrhage, telangiectasia; the levels of TNF-α, IL-1β, IL-6, MDA and NF-κB p65 protein expression in lung tissue were significantly higher than those in the normal control group and sham operation group [TNF-α (ng/L): 132.81±16.15 vs. 45.08±5.98, 46.10±6.72, IL-1β (ng/L): 137.32±15.22 vs. 51.03±7.89, 50.92±8.13; IL-6 (ng/L): 138.39±14.28 vs. 51.68±7.03, 52.48±7.36; MDA (kU/g): 1.79±0.13 vs. 0.96±0.05, 0.97±0.05; NF-κB p65 protein (NF-κB p65/GAPDH): 2.82±0.23 vs. 1.76±0.12, 1.82±0.13; all P < 0.05], the activity of SOD decreased significantly (kU/g: 45.90±5.46 vs. 92.11±10.13, 93.36±10.56, both P < 0.05). The changes in lung histopathology in the forsythiaside A intervention group were obviously improved as compared with the model group, which showed less inflammatory cell infiltration, less alveolar septum thickening, less bleeding and more intact structures; the levels of TNF-α, IL-1β, IL-6, MDA and the expression of NF-κB p65 protein in lung tissue were significantly lower than those in the model group [TNF-α (ng/L): 72.48±9.78 vs. 132.81±16.15, IL-1β (ng/L): 83.85±12.46 vs. 137.32±15.22, IL-6 (ng/L): 81.88±11.89 vs. 138.39±14.28, MDA (kU/L): 1.29±0.09 vs. 1.79±0.13, NF-κB p65 protein (NF-κB p65/GAPDH): 2.29±0.19 vs. 2.82±0.23, all P < 0.05], SOD activity increased significantly (kU/g: 66.03±7.98 vs. 45.90±5.46, P < 0.05). Conclusions:Forsythiaside A can effectively alleviate ALI in septic rats. The mechanism may be related to down-regulate the expression of NF-κB p65 and reduce the level of inflammatory factors and free radicals in lung tissue, thereby against acute lung injury in septic rats.

[Preparation and in vitro evaluation of forsythoside A-loaded exosomes].

A drug delivery system of forsythoside A-loaded exosomes(FTA-Exos) with high biocompatibility and low immunogenicity was established to investigate its impact on the migration of human lung epithelial adenocarcinoma A549 cells. The exosomes from A549 cells were extracted and purified by ultra-high speed centrifugation and ultrafiltration. FTA-Exos were prepared by ultrasonic incubation, and characterized by particle size analysis, transmission electron microscopy, and Western blot assay. The uptake of FTA-Exos by A549 cells was observed under the laser confocal microscope, and the impact of FTA-Exos on the migration of A549 cells was investigated by cell scratch assay. The results showed that the average particle size of the prepared FTA-Exos was(138.90±2.37) nm, which increased slightly after drug loading. The PDI was 0.291±0.013, and the average potential was(-10.1±0.66) mV. The FTA-Exos were spheroidal in appearance as observed by transmission electron microscope, with an obvious saucer-like double-layer membrane. Western blot assay indicated that the specific proteins CD63 and Alix were both expressed in exosomes. The laser confocal microscopy suggested that FTA-Exos were taken up by A549 cells and stably maintained in the cell for 4-8 h, and the fluorescence was significantly enhanced at 4 h. The scratch assay showed that the inhibitory effect of FTA-Exos on the migration of A549 cells was significantly stronger than that of forsythoside A(P < 0.05). In conclusion, the drug delivery system of FTA-Exos established in this study had good stability, reliable preparation process, and potent inhibitory effect on the migration of A549 cells in vitro, which can provide an important reference for subsequent in-depth research and application.

A review of pharmacological and pharmacokinetic properties of Forsythiaside A.

Traditional Chinese medicine plays a significant role in the treatment of various diseases and has attracted increasing attention for clinical applications. Forsythiae Fructus, the dried fruit of Forsythia suspensa (Thunb.) Vahl, is a widely used Chinese medicinal herb in clinic for its extensive pharmacological activities. Forsythiaside A is the main active index component isolated from Forsythiae Fructus and possesses prominent bioactivities. Modern pharmacological studies have confirmed that Forsythiaside A exhibits significant activities in treating various diseases, including inflammation, virus infection, neurodegeneration, oxidative stress, liver injury, and bacterial infection. In this review, the pharmacological activities of Forsythiaside A have been comprehensively reviewed and summarized. According to the data, Forsythiaside A shows remarkable anti-inflammation, antivirus, neuroprotection, antioxidant, hepatoprotection, and antibacterial activities through regulating multiple signaling transduction pathways such as NF-κB, MAPK, JAK/STAT, Nrf2, RLRs, TRAF, TLR7, and ER stress. In addition, the toxicity and pharmacokinetic properties of Forsythiaside A are also discussed in this review, thus providing a solid foundation and evidence for further studies to explore novel effective drugs from Chinese medicine monomers.

Forsythiaside a plays an anti-inflammatory role in LPS-induced mastitis in a mouse model by modulating the MAPK and NF-κB signaling pathways.

Forsythiaside A, a major bioactive component extracted from Forsythiae fructus, possesses multiple biological properties, especially anti-inflammatory properties. In the present study, the anti-inflammatory effect of forsythiaside A was investigated in lipopolysaccharide (LPS)-induced acute mastitis in mice. Our results showed that the expression levels of IL-1ß, IL-6, TNF-α, p38 MAPK, IκBα, and NF-κB p65 in the LPS group were all up-regulated, and obvious pathological changes were observed by sectioning. Compared with those in the LPS group, the expression levels of the above factors were significantly reduced, and the inflammation symptoms were also significantly reduced by section observation after forsythiaside A intervention. These results indicated that forsythiaside A effectively inhibited LPS-induced mammary inflammation in mice by attenuating the activation of the NF-κB and p38 MAPK signaling pathways.