Protocatechuic acid inhibits proliferation, migration and inflammatory response in rheumatoid arthritis fibroblast-like synoviocytes

Liquid chromatography-mass spectrometry-based strategy for systematic profiling of chemical components and associated quantitative analysis of quality markers in Qi-Wei-Tong-Bi oral liquid

Qi-Wei-Tong-Bi oral liquid (QWTB), a famous Chinese medicine preparation composed of seven crude drugs has a good therapeutic effect on rheumatoid arthritis and is widely used in China. However, its chemical composition and quality control have not been comprehensively and systematically investigated. In this study, high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry was employed for its chemical profiling. As a result, 100 components were chemically characterized. Additionally, high-performance liquid chromatography coupled with a quadrupole linear ion trap mass spectrometry method was developed to simultaneously quantify nine bioactive components (hyperoside, ononin, quercetin, sinomenine, magnoflorine, gallic acid, protocatechuic acid, monotropein, and cyclo-(Pro-Tyr)) in multiple-reaction monitoring mode. After successful validation in terms of linearity, precision, repeatability, and recovery, the assay method was applied for the determination of 10 batches of QWTB. The results showed that QWTB was enriched in sinomenine and magnoflorine with the highest amount up to hundreds or even thousands of µg/mL, while quercetin, ononin, cyclo-(Pro-Tyr), and hyperoside were much lower with the lowest content below 10 µg/mL. This study work would help to reveal the chemical profiling and provide a valuable and reliable approach for quality evaluation and even pharmacodynamic material basis studies of QWTB.

Screening of the key response component groups and mechanism verification of Huangqi-Guizhi-Wuwu-Decoction in treating rheumatoid arthritis based on a novel computational pharmacological model

BACKGROUND

Rheumatoid arthritis (RA) is a chronic autoimmune disease characterized by the destruction of synovial tissue and articular cartilage. Huangqi-Guizhi-Wuwu-Decoction (HGWD), a formula of Traditional Chinese Medicine (TCM), has shown promising clinical efficacy in the treatment of RA. However, the synergistic effects of key response components group (KRCG) in the treatment of RA have not been well studied.

METHODS

The components and potential targets of HGWD were extracted from published databases. A novel node influence calculation model that considers both the node control force and node bridging force was designed to construct the core response space (CRS) and obtain key effector proteins. An increasing coverage coefficient (ICC) model was employed to select the KRCG. The effectiveness and potential mechanism of action of KRCG were confirmed using CCK-8, qPCR, and western blotting.

RESULTS

A total of 796 key effector proteins were identified in CRS. The Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) analyses confirmed their effectiveness and reliability. In addition, 59 components were defined as KRCG, which contributed to 85.05% of the target coverage of effective proteins. Of these, 677 targets were considered key reaction proteins, and their enriched KEGG pathways accounted for 84.89% of the pathogenic genes and 87.94% of the target genes. Finally, four components (moupinamide, 6-Paradol, hydrocinnamic acid, and protocatechuic acid) were shown to inhibit the inflammatory response in RA by synergistically targeting the cAMP, PI3K-Akt, and HIF-1α pathways.

CONCLUSIONS

We have introduced a novel model that aims to optimize and analyze the mechanisms behind herbal formulas. The model revealed the KRCG of HGWD for the treatment of RA and proposed that KRCG inhibits the inflammatory response by synergistically targeting cAMP, PI3K-Akt, and HIF-1α pathways. Overall, the novel model is plausible and reliable, offering a valuable reference for the secondary development of herbal formulas.

Microplastics aggravates rheumatoid arthritis by affecting the proliferation/migration/inflammation of fibroblast-like synovial cells by regulating mitochondrial homeostasis

Rheumatoid arthritis (RA) is an autoimmune disease involving multiple joints. RA is a systemic disease characterized by chronic synovial inflammation and destruction of articular cartilage and bone. As a new pollutant, microplastics can enter the body through the respiratory and digestive tract and cause health damage. However, to date, the impact of microplastics on RA has not been revealed. Therefore, in the current research, we explored the impact of microplastics on RA. First, FLS (fibroblast-like synoviocytes) from RA was isolated and identified. FLS has been used as a cell model in vivo to study the potential impact of microplastics on FLS. Therefore, a series of biochemical experiments have been carried out, such as indirect immunofluorescence, western blotting and flow cytometry. First, we found that microplastics promote the proliferation of RA-FLSs through the MTT assay and the detection of cell proliferation markers and the cell cycle analysis through flow cytometry. On this basis, further research showed that microplastics also promoted the invasion and migration ability of RA-FLSs through Transwell experiments. In addition, microplastics also promote the secretion of inflammatory factors in RA-FLSs. In in vivo studies, the effect of microplastics on RA cartilage damage was evaluated. The results showed that RA cartilage damage was aggravated by microplastics, as determined by Alcian blue, toluidine blue and safranin O-fast green staining. Current research shows that microplastics, as a new pollutant, can promote sustained damage in RA.

Agglomerated serum albumin adsorbed protocatechuic acid coated superparamagnetic iron oxide nanoparticles as a theranostic agent

Iron oxide nanoparticles have been one of the most widely used nanomaterials in biomedical applications. However, the incomplete understanding of the toxicity mechanisms limits their use in diagnosis and treatment processes. Many parameters are associated with their toxicity such as size, surface modification, solubility, concentration and immunogenicity. Further research needs to be done to address toxicity-related concerns and to increase its effectiveness in various applications. Herein, colloidally stable nanoparticles were prepared by coating magnetic iron oxide nanoparticles (MIONPs) with protocatechuic acid (PCA) which served as a stabilizer and a linkage for a further functional layer. A new perfusion agent with magnetic imaging capability was produced by the adsorption of biocompatible passivating agent macro-aggregated albumin (MAA) on the PCA-coated MIONPs. PCA-coated MIONPs were investigated using infrared spectroscopy, thermogravimetric analysis and dynamic light scattering while adsorption of MAA was analysed by transmission electron microscopy, Fourier-transform infrared spectroscopy and x-ray diffraction methods. Magnetic measurements of samples indicated that all samples showed superparamagnetic behaviour. Cytotoxicity results revealed that the adsorption of MAA onto PCA-coated MIONPs provided an advantage by diminishing their toxicity against the L929 mouse fibroblast cell line compared to bare Fe₃O₄.

Ethyl Protocatechuate Encapsulation in Solid Lipid Nanoparticles: Assessment of Pharmacotechnical Parameters and Preliminary In Vitro Evaluation for Colorectal Cancer Treatment

Colorectal cancer is one of the most diffused tumoral diseases. Since most medicaments employed for its treatment are debilitating, the use of naturally derived products, which can be effective against the mutated cells and, in addition, can reduce most inflammatory-related effects, could be extremely beneficial for the continued treatment of this disease. In this research, ethyl protocatechuate (PCAEE), a protocatechuic acid prodrug, was encapsulated in solid lipid nanoparticles (SLN) (prepared without and with Tween 80), which were characterized in terms of size, polydispersity index (PDI), zeta potential and thermotropic behavior. Encapsulation efficiency, release profile and interaction with a model of biomembrane were also assessed. The nanoparticles were tested in vitro on both healthy cells and on a model of tumoral cells. SLN prepared with Tween 80 was promising in terms of physicochemical properties (z-average of 190 nm, PDI 0.150 and zeta potential around -20 mV) and encapsulation efficiency (56%); they showed a desirable release profile, demonstrated an ability to penetrate and release the encapsulated PCAEE into a biomembrane model and were nontoxic on healthy cells. In addition, they caused a greater dose-dependent decrease in the viability of CaCo-2 cells than PCAEE alone. In conclusion, the formulation could be proposed for further studies to assess its suitability for the treatment of colorectal cancer.

Protocatechuic acid reduces H2O2-induced migration and oxidative stress of fibroblast-like synoviocytes in rheumatoid arthritis by activating Nrf2-Keap1 signaling pathway

Honeycomb (Nidus vespae) is traditional Chinese medicine and can treat rheumatoid arthritis (RA), and protocatechuic acid (PCA) is a bioactive component of honeycomb. This study aimed to investigate whether PCA could reduce the H₂O₂-induced migration and oxidative stress of RA fibroblast-like synoviocytes (RA-FLSs). H₂O₂-induced RA-FLSs were used to simulate the in vitro model of RA. The viability, apoptosis, migration, invasion, and oxidative stress of RA-FLSs were detected by Cell Counting Kit-8 (CCK-8), terminal deoxynucleotidyl transferase dUTP nick-end labeling assay, wound healing, transwell assays, DCFDA staining, and malonaldehyde and superoxide dismutase enzyme-linked immunosorbent assay kits. The expression of migration and invasion-related proteins and Nrf2/Keap1 signaling pathway-related proteins was analyzed by western blotting. As a result, PCA suppressed the viability, migration, invasion, and oxidative and promoted apoptosis of H₂O₂-induced RA-FLSs by activating the Nrf2/Keap1 signaling pathway. ML-385, an Nrf2 inhibitor, could enhance the viability, migration, invasion, and oxidative and inhibited apoptosis of H₂O₂-induced RA-FLSs. In conclusion, PCA reduced H₂O₂-induced migration and oxidative stress of RA-FLSs by activating the Nrf2-Keap1 signaling pathway.

Transcriptomic profiling revealed the role of apigenin-4'-O-α-L-rhamnoside in inhibiting the activation of rheumatoid arthritis fibroblast-like synoviocytes via MAPK signaling pathway

BACKGROUND

Activated fibroblast-like synoviocyte (FLS) played a significant role in the pathogenesis and progression of rheumatoid arthritis (RA). Apigenin-4'-O-α-L-rhamnoside showed remarkable effects against RA, however, no relevant studies on pharmacology of apigenin-4'-O-α-L-rhamnoside yet, the effects and underlying molecular mechanism of apigenin-4'-O-α-L-rhamnoside on RA are still unclear.

PURPOSE

This study aimed to investigate the therapeutic effects and mechanisms of apigenin-4'-O-α-L-rhamnoside on RA-FLS cells by transcriptomic analysis.

METHODS

In vitro, RA-FLS cell viability and migration were measured by CCK-8 and scratch assays, respectively. The effects of apigenin-4'-O-α-L-rhamnoside on inflammatory levels of MMP-1, MMP-3, RANKL and TNF-α in RA-FLS cells were detected using ELISA kits. High-throughput transcriptome analysis was performed to screen the key genes and related pathways of apigenin-4'-O-α-L-rhamnoside inhibit RA-FLSs, and the result of which were validated by RT-qPCR and western blot. Furthermore, in vivo, we also evaluated the effects of apigenin-4'-O-α-L-rhamnoside in rat with CIA.

RESULTS

Apigenin-4'-O-α-L-rhamnoside significantly suppressed RA-FLS migration, exerted remarkable inhibiting effects on the expression levels on MMP-1, MMP3, RANKL and TNF-α in RA-FLS cells. It seemed that MAPK signaling pathway might be closely related to the pathogenesis of RA by down-regulated relevant core targets (MAPK1, HRAS, ATF-2, p38 and JNK). Moreover, apigenin-4'-O-α-L-rhamnoside attenuated the severity of arthritis in CIA rat.

CONCLUSION

Apigenin-4'-O-α-L-rhamnoside inhibited pro-inflammatory cytokine, chemokine and MMPs factors production of RA-FLS by targeting the MAPK signaling pathway, which provided a scientific basis for potential application in the treatment of RA.

MiR-449b-5p Regulates the Proliferation and Migration of Cervical Cancer Cells by Targeting Forkhead Box Protein P1 (FOXP1)

This study intends to assess miR-449b-5p’s effect on cervical cancer (CC) cells and its mechanism. After transfection of miR-449b-5p mimics, inhibitor, si-Foxp1 and negative control, CC cell viability was analyzed by MTT along with analysis of migration and invasion by transwell and scratch test, and Foxp1 protein level by Western blot. CC cells presented a significantly higher miR-449b-5p level and lower Foxp1 level in relative to normal cervical cells. miR-449b-5p mimic transfection significantly promoted CC cell viability, migration and invasion and decreased Foxp1 expression. However, all the above changes were significantly reversed after treatment with si-Foxp1. In conclusion, miR-449b-5p level is elevated in CC cells and its overexpression promotes the biological behaviors of CC cells possibly through targeting Foxp1, indicating that it might be a new target for the treatment of CC.

Protocatechuic acid protects against thioacetamide-induced chronic liver injury and encephalopathy in mice via modulating mTOR, p53 and the IL-6/ IL-17/ IL-23 immunoinflammatory pathway

Protocatechuic acid (PCA), a natural phenolic acid, is known for antioxidant, anti-inflammatory, anti-apoptotic, and anti-fibrotic activities. However, the protective mechanisms of PCA on thioacetamide (TAA)-induced liver/brain injury are not well addressed. Chronic liver injury was induced in mice by intraperitoneal injection of TAA (200 mg/kg, 3 times/week) for 8 weeks. Simultaneously, PCA (100, 150 mg/kg/day, p.o.) was given daily from the 4th week. Protocatechuic acid ameliorated liver and brain damage indicated by the decrease in serum activities of aminotransferases, gamma-glutamyl transferase, alkaline phosphatase, lactate dehydrogenase, levels of bilirubin, and ammonia concomitant with restoration of normal albumin levels. Additionally, PCA treatment ameliorated oxidative stress in liver and brain, confirmed by the decrease in malondialdehyde and nitric oxide levels and the increase in antioxidant activities. Moreover, PCA showed anti-inflammatory actions through downregulation of TNF-α expression in the liver and IL-6/IL-17/IL-23 levels in the brain, which is confirmed by the decrease in CD4⁺ T brain cell numbers. Most importantly, PCA treatment showed a significant decrease in mTOR level and number of LC3 positive cells in both liver and brain tissues. Consequently, PCA could inhibit mTOR-induced apoptosis, as it showed anti-apoptotic actions through downregulation of caspase-3 expression in liver and p53 expression in liver and brain. Furthermore, liver and brain tissues of treated mice showed restoration of normal histology. It can be concluded that, several mechanisms, including: antioxidant, anti-inflammatory, anti-autophagic and anti-apoptotic activities can be implicated in the hepato- and neuroprotective potentials of PCA.

Towards a better understanding of Fagopyrum dibotrys: a systematic review

Fagopyrum dibotrys (F. dibotrys) (D.Don) H.Hara is a well-known edible herbal medicine in Asian countries. It has been widely used for the treatment of lung diseases, swelling, etc., and is also an important part of many Chinese medicine prescriptions. At present, more than 100 compounds have been isolated and identified from F. dibotrys, and these compounds can be primarily divided into flavonoids, phenols, terpenes, steroids, and fatty acids. Flavonoids and phenolic compounds are considered to be the main active ingredients of F. dibotrys. Previous pharmacological studies have shown that F. dibotrys possesses anti-inflammatory, anti-cancer, anti-oxidant, anti-bacterial, and anti-diabetic activities. Additional studies on functional genes have led to a better understanding of the metabolic pathways and regulatory factors related with the flavonoid active ingredients in F. dibotrys. In this paper, we systemically reviewed the research advances on the phytochemistry and pharmacology of F. dibotrys, as well as the functional genes related to the synthesis of active ingredients, aiming to promote the development and utilization of F. dibotrys.

Lentivirus-Mediated Overexpression or Silencing of Aquaporin 1 Affects the Proliferation, Migration and Invasion of TNF-α-Stimulated Rheumatoid Arthritis Fibroblast-Like Synoviocytes by Wnt/β-Catenin Signaling Pathway

Introduction

Previous studies have confirmed the pathologic role of synovial aquaporin 1 (AQP1) in rheumatoid arthritis (RA), but its associations with the abnormal biologic behaviors of fibroblast-like synoviocytes (FLS) remain unclear. Herein, we examined the roles of AQP1 in the proliferation, migration and invasion of TNF-α-stimulated RA FLS (MH7A cells) and explored the underlying mechanisms.

Materials and Methods

Lentivirus-mediated AQP1 overexpression or silencing MH7A cells was constructed. Assays of MTT, flow cytometry (PI staining and Annexin V-PE/7-AAD staining), TMRM staining, wound-healing, transwell and phalloidin staining were performed to detect cell proliferation, cycle distribution, apoptosis, migration and invasion. The involvement of Wnt/β-catenin pathway was revealed by Western blot and β-catenin immunofluorescence staining.

Results

AQP1 overexpression promoted cell proliferation of TNF-α-stimulated MH7A by facilitating transformation from G0/G1 to S phase and inhibiting cell apoptosis (ie, reduced apoptosis rates, raised mitochondrial membrane potential, increased Bcl-2 protein level and decreased levels of Bax and cleaved caspase 3 protein). Also, AQP1 overexpression increased the migration index as well as the numbers of migrated and invasive cells. Furthermore, AQP1 overexpression promoted the activation of Wnt/β-catenin pathway, and XAV939, an inhibitor of Wnt/β-catenin, canceled the above effects of AQP1 overexpression on MH7A cells. As expected, AQP1 silencing exhibited the opposite effects on TNF-α-stimulated MH7A cells, which could be reversed by LiCl, an activator of Wnt/β-catenin.

Conclusion

AQP1 can affect the proliferation, migration and invasion of MH7A cells by Wnt/β-catenin signaling pathway, and AQP1 can be as a crucial determiner that can regulate RA FLS biologic behaviors.

The protective effect of protocatechuic acid on hepatotoxicity induced by cisplatin in mice

Cisplatin is one of the most potent anti-cancer drugs used for the treatment of various solid tumors, yet it has several side effects that may limit its clinical use. Hepatotoxicity is one of the most serious side effects as it may lead to liver failure. Several mechanisms including oxidative stress, inflammation, and apoptosis have been examined in cisplatin-induced hepatotoxicity. Protocatechuic acid (Proto) which is naturally occurring phenolic acid has shown different biological activity as antioxidant, anti-inflammatory, and anti-apoptotic. In this study, we investigate the protective effect of Proto at two doses 100 and 150 mg/kg on hepatotoxicity induced by a single injection of 10 mg/kg cisplatin in female albino mice. The present study demonstrates for the first time that Proto administration (100 and 150 mg/Kg) significantly attenuates cisplatin-induced changes in liver function [increase serum albumin and decrease liver injury markers ALT, AST, GGT, and bilirubin]. This was associated with marked hepatic antioxidant effects [decrease MDA and NO levels, increase GSH and SOD activity]. Moreover, Proto reduced cisplatin-induced apoptosis in the liver through decreasing caspase-3, annexin-V, and BAX. Both doses suppressed cisplatin-induced expression of iNOS and NF-ᴋB p65 subunit and pro-inflammatory cytokines (IL-6 and TNF-α). Also, Proto improved histopathological examination of the liver. The present findings reveal that the antioxidant, anti-inflammatory, and anti-apoptotic effects of Proto are the main mechanisms by which Proto can ameliorate cisplatin-induced liver injury.

MicroRNA-137-mediated inhibition of lysine-specific demethylase-1 prevents against rheumatoid arthritis in an association with the REST/mTOR axis

BACKGROUND

It has been increasingly reported that microRNAs (miRNAs) are related to rheumatoid arthritis (RA) pathogenesis. This present research was conducted to analyze the functions of miR-137 and the underlying molecular mechanism in RA progression.

METHODS

Differentially expressed miRNAs in RA patients were analyzed using microarray-based analyses. Next, experiments involving miR-137 overexpression were performed to analyze the role of miR-137 in human fibroblast-like synoviocytes-RA (HFLS-RA) using cell counting kit-8 (CCK-8) assay, EdU staining, Transwell assay and flow cytometry, respectively. The function of miR-137 in inflammation was determined using ELISA. The binding relationship between miR-137 and LSD1 was confirmed by dual-luciferase reporter gene assay and ChIP test. Besides, a rat model with RA was established for in vivo experiments.

RESULTS

miR-137 was downregulated in RA tissues and cells, which was negatively correlated with inflammatory factors. Upregulated miR-137 suppressed growth, migration and invasion of HFLS-RA, but promoted apoptosis. Lysine-specific demethylase-1 (LSD1) was a target of miR-137 and could be negatively regulated by miR-137. Moreover, LSD1 could activate REST through demethylation, while the REST/mTOR pathway induced levels of pro-inflammatory factors in RA. We observed the similar results in our in vivo study.

CONCLUSION

This study suggested that miR-137 reduced LSD1 expression to inhibit the activation of REST/mTOR pathway, thus preventing against inflammation and ameliorating RA development. Our research may offer new insights into treatment of RA.