Paeoniflorin inhibits IL‑1β‑induced expression of inflammatory mediators in human osteoarthritic chondrocyte

Network Pharmacology-Based Approach to Investigate the Active Ingredients and Therapeutic Mechanisms of Jingu Tongxiao Pill against Osteoarthritis

This study aimed to investigate the active ingredients and therapeutic mechanisms of Jingu Tongxiao Pill (JGTXP), a commonly used Chinese patent medicine, in treating osteoarthritis (OA) via network pharmacology analysis combined with experimental validation. First, we administered JGTXP to rat plasma and identified the candidate active compounds. Next, target prediction, protein-protein interaction, compound-target network construction, gene ontology (GO), and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses were conducted for JGTXP. Lastly, the network-derived key targets and pathways were validated in vitro and in vivo. Finally, we identified 106 compounds in JGTXP and 24 absorbed compounds in the rat plasma. Network analysis revealed that JGTXP interferes with OA mainly via regulating the inflammatory response, collagen catabolic process, and osteoclast differentiation, and the nuclear factor kappa B (NF-κB) signaling pathway plays a pivotal role in these processes. Experimentally, JGTXP exerted potential protective effects on articular cartilage and inhibited expression of inflammatory mediators and collagen catabolism-related proteins, including interleukin 1 beta (IL-1β), interleukin 6, tumor necrosis factor alpha (TNF-α), and matrix metalloproteinase (MMP) 3 and MMP13, in a papain-induced OA rat model. Consistently, mRNA expression levels of these factors and nitric oxide release were suppressed by JGTXP in an LPS-induced RAW 264.7 inflammation model. The reporter gene assay showed that JGTXP could reduce the transcriptional activity of NF-κB. Consecutive western blot analysis demonstrated that nuclear NF-κB p65, inducible nitric oxide synthase (iNOS), and cyclooxygenase 2 (COX-2) expression were inhibited while cytoplasmic NF-κB p65 was upregulated by JGTXP. Using a combination of chemical profiling, network pharmacology analysis, and experimental validation, we preliminarily clarified the active ingredients of JGTXP intervention for OA and demonstrated that JGTXP ameliorates OA, at least partially, by regulating the NF-κB signaling pathway.

Therapeutic Single Compounds for Osteoarthritis Treatment

Osteoarthritis (OA) is an age-related degenerative disease for which an effective disease-modifying therapy is not available. Natural compounds derived from plants have been traditionally used in the clinic to treat OA. Over the years, many studies have explored the treatment of OA using natural extracts. Although various active natural extracts with broad application prospects have been discovered, single compounds are more important for clinical trials than total natural extracts. Moreover, although natural extracts exhibit minimal safety issues, the cytotoxicity and function of all single compounds in a total extract remain unclear. Therefore, understanding single compounds with the ability to inhibit catabolic factor expression is essential for developing therapeutic agents for OA. This review describes effective single compounds recently obtained from natural extracts and the possibility of developing therapeutic agents against OA using these compounds.

Validation of the Key Active Ingredients and Anti-Inflammatory and Analgesic Effects of Shenjin Huoxue Mixture Against Osteoarthritis by Integrating Network Pharmacology Approach and Thin-Layer Chromatography Analysis

Background

Shenjin Huoxue Mixture (SHM), a classic traditional herb mixture has shown significant clinical efficacy against osteoarthritis (OA). Our previous experimental study has confirmed its anti–inflammatory and analgesic effect on acute soft tissue injury in rats, with the compound of glycyrrhizinate in SHM identified and the content of paeoniflorin in SHM determined by high-performance liquid chromatography (HPLC). However, the components and its pharmacological mechanisms of SHM against OA have not been systematically elucidated yet. Thus this study aimed to predict the key active ingredients and potential pharmacological mechanisms of SHM in the treatment of OA by network pharmacology approach and thin-layer chromatography (TLC) validation.

Methods

The active ingredients of SHM and their targets, as well as OA-related targets, were identified from databases. The key active ingredients were defined and ranked by the number of articles retrieved in PubMed using the keyword “(the active ingredients [Title/Abstract]) AND Osteoarthritis[Title/Abstract] ”, and validated partially by TLC. The pharmacological mechanisms of SHM against OA were displayed by GO term and Reactome pathway enrichment analysis with Discovery Studio 3.0 software docking to testing the reliability.

Results

Finally, 16 key active ingredients were identified and ranked, including quercetin validated through TLC. Inflammatory response, IL-6 signaling pathway and toll-like receptor (TLR) cascades pathway were predicted as the main pharmacological mechanisms of SHM against OA. Especially, 12 out of 16 key active ingredients, including validated quercetin, were well docked to IL-6 proteins.

Conclusion

Our results confirmed the anti–inflammatory and analgesic effect of SHM against OA through multiple components, multiple targets and multiple pathways, which revealed the theoretical basis of SHM against OA and may provide a new drug option for treating OA.

Paeoniflorin Alleviates H2O2-Induced Oxidative Injury Through Down-Regulation of MicroRNA-135a in HT-22 Cells

Paeoniflorin (PF) has been reported to possess neuroprotective influences on cognitive dysfunction illness. In current research, we attempted to probe into the protective influences of PF against H₂O₂-induced damage and the underlying regulating mechanisms on hippocampal HT-22 cells. HT-22 cells were pretreated with PF, and then induced by H₂O₂. Afterwards, the influences of PF pretreatment were examined using CCK-8 assay, apoptosis assay, western blot and ROS assay, respectively. In addition, the expression of microRNA-135a (miR-135a) was analyzed and altered by qRT-PCR and cell transfection, respectively. After overexpression of miR-135a, the effects of miR-135a mimic on cell functions were detected again. Moreover, influences of H₂O₂, PF and miR-135a overexpression on JAK2/STAT3 and ERK1/2 signal pathways were further investigated. Further experiments verified that PF pretreatment alleviated H₂O₂-induced oxidative stress through increasing cell viability, inhibiting cell apoptosis, reducing ROS generation and activating JAK2/STAT3 and ERK1/2 pathways. Besides, expression of miR-135a was declined by PF pretreatment. Whereas, miR-135a mimic abrogated the protective effects triggered by PF pretreatment. These results indicated that PF can alleviate H₂O₂-induced oxidative stress by down-regulation of miR-135a via activation of JAK2/STAT3 and ERK1/2 pathways.

Effect of paeoniflorin on cardiac remodeling in chronic heart failure rats through the transforming growth factor β1/Smad signaling pathway

Background

Cardiac remodeling is an important mechanism for the occurrence and development of chronic heart failure (CHF). Paeoniflorin (Pae) is the main active ingredient of Chinese herbaceous peony and has novel anti-inflammatory effect. This study was conducted to assess the effects and mechanisms of Pae on cardiac remodeling in CHF rats.

Methods

A cardiac remodeling rat model was induced by isoprenaline (Iso). Pae (20 µg/kg/d) was administrated to CHF rats for six weeks. Cardiac ultrasound was used to assess the structure and function of CHF rats. Collagen volume fraction (CVF) and perivascular collagen volume area of myocardial tissues were calculated. With real-time polymerase chain reaction and Western blot, the protein and mRNA levels of transforming growth factor β1 (TGF-β1) and Smad3 were detected.

Results

Compared to Iso group, Pae can alleviate cardiac remodeling and improve cardiac function in CHF rats. The levels of CVF and perivascular collagen volume area reduced in Pae group (P<0.05). The expression of TGF-β1 and Smad3 protein decreased in Pae and Cap group (P<0.05). Further, the expression of TGF-β1 and Smad3 mRNA also decreased markedly in the Pae group (P<0.05).

Conclusions

Pae could attenuate cardiac remodeling and improve cardiac function in CHF rats. The potential mechanism for the cardioprotective effect of Pae may be highly associated with the down-regulating of TGF-β1/Smad signaling pathway.

The Regulatory Effects of Paeoniflorin and Its Derivative Paeoniflorin-6'-O-Benzene Sulfonate CP-25 on Inflammation and Immune Diseases

The plant extract "total glucosides of peony" (TGP) constitutes a mixture of glycosides that is isolated from the roots of the well-known traditional Chinese herb Paeonia lactiflora Pall. Paeoniflorin (Pae) is the most abundant component and the main biologically active ingredient of TGP. Pharmacologically, Pae exhibits powerful anti-inflammatory and immune regulatory effects in some animal models of autoimmune diseases including Rheumatoid Arthritis (RA) and Systemic Lupus Erythematosus (SLE). Recently, we modified Pae with an addition of benzene sulfonate to achieve better bioavailability and higher anti-inflammatory immune regulatory effects. This review summarizes the pharmacological activities of Pae and the novel anti-inflammatory and immunomodulatory agent Paeoniflorin-6'-O-benzenesulfonate (CP-25) in various chronic inflammatory and autoimmune disorders. The regulatory effects of Pae and CP-25 make them promising agents for other related diseases, which require extensive investigation in the future.

Paeoniflorin inhibits IL-1β-induced MMP secretion via the NF-κB pathway in chondrocytes

Paeoniflorin serves important cellular roles, exerting anti-cancer, anti-inflammatory and anti-pulmonary fibrosis effects and possesses immune-modulatory properties. However, the exact role of paeoniflorin in the pathogenesis of osteoarthritis (OA) remains unclear. The aim of the present study was to investigate the effects of paeoniflorin on articular surfaces in vitro. Rat chondrocytes were cultured in vitro and an MTT assay was performed to assess chondrocyte survival. Following treatment with interleukin (IL)-1β and paeoniflorin, the production of matrix metalloproteinases (MMPs) and tissue inhibitor of metalloproteinases-1 (TIMP-1) was examined using reverse transcription-quantitative polymerase chain reaction and western blotting. The interleukin (IL)-1β-induced nuclear factor (NF)-κB pathway activation was also investigated. The results demonstrated that paeoniflorin was able to downregulate the expression of MMP and increase the expression of TIMP-1ntmRNA and protein in IL-1β-induced rat chondrocytes. Furthermore, treating chondrocytes with paeoniflorin blocked the activation of NF-κB. These results suggest that paeoniflorin may serve am anti-catabolic role in the progression of OA and may be an effective preventative treatment for OA.