Paeoniflorin inhibits Th1 and Th17 cells in gut-associated lymphoid tissues to produce anti-arthritis activities

Genus Paeonia monoterpene glycosides: A systematic review on their pharmacological activities and molecular mechanisms

BACKGROUND

Genus Paeonia, which is the main source of Traditional Chinese Medicine (TCM) Paeoniae Radix Rubra (Chishao in Chinese), Paeoniae Radix Alba (Baishao in Chinese) and Moutan Cortex (Mudanpi in Chinese), is rich in active pharmaceutical ingredient such as monoterpenoid glycosides (MPGs). MPGs from Paeonia have extensive pharmacological effects, but the pharmacological effects and molecular mechanisms of MPGs has not been comprehensively reviewed.

PURPOSE

MPGs compounds are one of the main chemical components of the genus Paeonia, with a wide variety of compounds and strong pharmacological activities, and the structure of the mother nucleus-pinane skeleton is similar to that of a cage. The purpose of this review is to summarize the pharmacological activity and mechanism of action of MPGs from 2012 to 2023, providing reference direction for the development and utilization of Paeonia resources and preclinical research.

METHODS

Keywords and phrases are widely used in database searches, such as PubMed, Web of Science, Google Scholar and X-Mol to search for citations related to the new compounds, extensive pharmacological research and molecular mechanisms of MPGs compounds of genus Paeonia.

RESULTS

Modern research confirms that MPGs are the main compounds in Paeonia that exert pharmacological effects. MPGs with extensive pharmacological characteristics are mainly concentrated in two categories: paeoniflorin derivatives and albiflflorin derivatives among MPGs, which contains 32 compounds. Among them, 5 components including paeoniflorin, albiflorin, oxypaeoniflorin, 6'-O-galloylpaeoniflorin and paeoniflorigenone have been extensively studied, while the other 28 components have only been confirmed to have a certain degree of anti-inflammatory and anticomplementary effects. Studies of pharmacological effects are widely involved in nervous system, endocrine system, digestive system, immune system, etc., and some studies have identified clear mechanisms. MPGs exert pharmacological activity through multilateral mechanisms, including anti-inflammatory, antioxidant, inhibition of cell apoptosis, regulation of brain gut axis, regulation of gut microbiota and downregulation of mitochondrial apoptosis, etc. CONCLUSION: This systematic review delved into the pharmacological effects and related molecular mechanisms of MPGs. However, there are still some compounds in MPGs whose pharmacological effects and pharmacological mechanisms have not been clarified. In addition, extensive clinical randomized trials are needed to verify the efficacy and dosage of MPGs.

Paeoniflorin alleviated muscle atrophy in cancer cachexia through inhibiting TLR4/NF-κB signaling and activating AKT/mTOR signaling

Cancer cachexia is a progressive wasting syndrome, which is mainly characterized by systemic inflammatory response, weight loss, muscle atrophy, and fat loss. Paeoniflorin (Pae) is a natural compound extracted from the dried root of Paeonia lactiflora Pallas, which is featured in anti-inflammatory, antioxidant, and immunoregulatory pharmacological activities. While, the effects of Pae on cancer cachexia had not been reported before. In the present study, the effects of Pae on muscle atrophy in cancer cachexia were observed both in vitro and in vivo using C2C12 myotube atrophy cell model and C26 tumor-bearing cancer cachexia mice model. In the in vitro study, Pae could alleviate myotubes atrophy induced by conditioned medium of C26 colon cancer cells or LLC Lewis lung cancer cells by decreasing the expression of Atrogin-1 and inhibited the decrease of MHC and MyoD. In the in vivo study, Pae ameliorated weight loss and improved the decrease in cross-sectional area of muscle fibers and the impairment of muscle function in C26 tumor-bearing mice. The inhibition of TLR4/NF-κB pathway and the activation of AKT/mTOR pathway was observed both in C2C12 myotubes and C26 tumor-bearing mice treated by Pae, which might be the main basis of its ameliorating effects on muscle atrophy. In addition, Pae could inhibit the release of IL-6 from C26 tumor cells, which might also contribute to its ameliorating effects on muscle atrophy. Overall, Pae might be a promising candidate for the therapy of cancer cachexia.

Prolonged administration of total glucosides of paeony improves intestinal immune imbalance and epithelial barrier damage in collagen-induced arthritis rats based on metabolomics-network pharmacology integrated analysis

Rheumatoid arthritis (RA) is a chronic systemic autoimmune disease characterized by synovial inflammation and joint damage with complex pathological mechanisms. In recent years, many studies have shown that the dysregulation of intestinal mucosal immunity and the damage of the epithelial barrier are closely related to the occurrence of RA. Total glucosides of paeony (TGP) have been used clinically for the treatment of RA in China for decades, while the pharmacological mechanism is still uncertain. The purpose of this study was to investigate the regulatory effect and mechanism of TGP on intestinal immunity and epithelial barrier in RA model rats. The results showed that TGP alleviated immune hyperfunction by regulating the ratio of CD3+, CD4+ and CD8+ in different lymphocyte synthesis sites of the small intestine, including Peyer's patches (PPs), intraepithelial lymphocytes (IELs), and lamina propria lymphocytes (LPLs). Specially, TGP first exhibited immunomodulatory effects on sites close to the intestinal lumen (IELs and LPLs), and then on PPs far away from the intestinal lumen as the administration time prolonged. Meanwhile, TGP restores the intestinal epithelial barrier by upregulating the ratio of villi height (V)/crypt depth (C) and expression of tight junction proteins (ZO-1, occludin). Finally, the integrated analysis of metabolomics-network pharmacology was also used to explore the possible regulation mechanism of TGP on the intestinal tract. Metabolomics analysis revealed that TGP reversed the intestinal metabolic profile disturbance in CIA rats, and identified 32 biomarkers and 163 corresponding targets; network pharmacology analysis identified 111 potential targets for TGP to treat RA. By intersecting the results of the two, three key targets such as ADA, PNP and TYR were determined. Pharmacological verification experiments showed that the levels of ADA and PNP in the small intestine of CIA rats were significantly increased, while TGP significantly decreased their ADA and PNP levels. In conclusion, purine metabolism may play an important role in the process of TGP improving RA-induced intestinal immune imbalance and impaired epithelial barrier.

Anti-inflammatory and pro-regenerative effects of a monoterpene glycoside on experimental periodontitis in a rat model of diabetes

OBJECTIVE

Paeoniflorin (Pae) is a monoterpene glycoside with immune-regulatory effects. Several studies have already demonstrated the impact of Pae on periodontitis, but its effect on diabetic periodontitis is unclear. In this study, our aim was to test the hypothesis that Pae had a strong anti-inflammatory effect that prevented bone loss in diabetic periodontitis.

METHODS

Thirty male Wistar albino rats were randomly divided into control (healthy, n = 10), periodontitis (PD) + diabetes (DM; n = 10), and PD + DM + Pae (n = 10) groups. Ligature-induced periodontitis was created by placing 4-0 silk ligatures around the lower first molars on both sides of the mandibulae. Experimental DM was created via an injection of 50 mg/kg and streptozotocin (STZ). Hyperglycemia was confirmed by the blood glucose levels of rats (>300 mg/dL). The bone mineral density (BMD), trabecular number, trabecular thickness, and bone loss were measured by micro-CT. The expression levels of IL-1β, IL-6, and TNF-α were measured in tissue homogenates by ELISA.

RESULTS

The PD + DM + Pae group had significantly less alveolar crest resorption when compared to the PD + DM group. There was also a significant difference between the PD + DM + Pae group compared to PD + DM group in trabecular thickness, BMD, and the number of trabeculae. Pae application led to a statistically significant decrease in IL-1β, IL-6, and TNF-α levels in diabetic periodontitis.

CONCLUSION

Systemic application of Pae suppressed inflammation caused by PD and DM, leading to reduced bone loss and enhanced bone quality.

Paeoniflorin inhibits proliferation and migration of psoriatic keratinocytes via the lncRNA NEAT1/miR-3194-5p/Galectin-7 axis

To investigate the mechanism underlying the effect of paeoniflorin (PF) on the proliferation and migration of psoriatic keratinocytes. The expressions of long noncoding RNA NEAT1, miR-3194-5p and Galectin-7 in skin tissues from psoriatic patients and healthy controls were detected. Psoriatic HaCat cells were used to investigate the function of NEAT1 and Galectin-7 as well as the effect and mechanism of PF in psoriasis. MTT, colony formation and scratch assays were used to assess the proliferation and migration of psoriatic HaCat cells. Dual-luciferase reporter assay was used to validate the interactions among NEAT1, miR-3194-5p and Galectin-7. NEAT1 and Galectin-7 were lowly expressed and miR-3194-5p was highly expressed in psoriatic patients. PF suppressed the proliferation and migration of psoriatic HaCat cells by elevating the expressions of NEAT1 and Galectin-7. NEAT1 positively mediated the expression of Galectin-7 by targeting miR-3194-5p. PF controls the proliferation and migration of psoriatic HaCat cells via the NEAT1/miR-3194-5p/Galectin-7 axis.

Gut and Vaginal Microbiomes in PCOS: Implications for Women's Health

PCOS is defined as a kind of endocrine and metabolic disorder which affects females at reproductive ages, is becoming much more common, nowadays. Microbiomes are known as microorganisms that inhabit the body to play a vital role in human health. In recent years, several basic and clinical studies have tried to investigate the correlation between the reproductive health/disorder and microbiomes (gut microbiomes and vaginal microbiomes). However, the mechanism is still unclear. In this review, we reviewed the relationship between PCOS and microbiomes, including gut/vaginal microbiomes compositions in PCOS, mechanism of microbiomes and PCOS, and then collectively focused on the recent findings on the influence of microbiomes on the novel insight regarding the therapeutic strategies for PCOS in the future clinical practice.

The monomer derivative of paeoniflorin inhibits macrophage pyroptosis via regulating TLR4/ NLRP3/ GSDMD signaling pathway in adjuvant arthritis rats

OBJECTIVE

This study was aimed to investigate the effect of monomer derivative of paeoniflorin (MDP) on macrophage pyroptosis mediated by TLR4/NLRP3/GSDMD signaling pathway in adjuvant arthritis (AA) rats.

METHOD

Wistar rats were divided into normal group, AA model group, MDP (50 mg/kg) group and MTX (0.5 mg/kg) group. The expression of TLR4, NLRP3 and GSDMD in macrophage were detected by immunofluorescence assay. The expression of TLR4 and the ratio of macrophage pyroptosis were analyzed by flow cytometry. Cell morphology was observed by scanning electron microscopy. The cytokine levels of IL-18 and IL-1β were detected by ELISA. The expressions of proteins related to macrophage pyroptosis were detected by western blot.

RESULTS

MDP has a therapeutic effect on rats AA by reducing the secondary inflammation and improving pathological changes. The results of X-ray imaging and ultrasound images showed that MDP could inhibit bone erosion, soft tissue swelling, and joint space narrowing. Macrophage pyroptosis was found in secondary inflammation of AA rats. The expressions of TLR4, MyD88, NLRP3, Caspase-1, ASC, and GSDMD-N in macrophage were increased, the levels of IL-18 and IL-1β were enhanced, and the morphology of pyroptosis could be observed. MDP could inhibit macrophage polarization and macrophage pyroptosis, and down-regulated the cytokine levels of IL-18 and IL-1β in AA rats. MDP could regulate the M1/M2 ratio, decreased the ratio of macrophage pyroptosis and down-regulated the expressions of TLR4, MyD88, NLRP3, Caspase-1, ASC, and GSDMD-N in vivo and in vitro.

CONCLUSION

Abnormal activation of TLR4/NLRP3/GSDMD signaling pathway may be involved in macrophage pyroptosis in AA rats. The therapeutic effect of MDP on AA rats is related to the inhibition of macrophage pyroptosis by regulating the TLR4/NLRP3/GSDMD signaling pathway.

Paeoniflorin inhibits IgE-mediated allergic reactions by suppressing the degranulation of mast cells though binding with FcϵRI alpha subunits

Paeoniflorin (PF), a monoterpene glycoside isolated from the aqueous extract of the Chinese herb Radix Paeoniae Alba, has been used for treating various inflammatory diseases. In this study, we aimed to investigate the anti-allergic activities of PF. The anti-anaphylactic activity of PF was investigated using mast cell (MC) degranulation assay as well as Ca²⁺ influx in vitro and skin swelling and extravasation assays in vivo. The results showed that PF inhibited MC degranulation (histamine release from 74.5 ± 4.95 ng/ml to 58.7 ± 6.06 ng/ml) and Ca²⁺ influx challenged by DNP-BSA in vitro. In addition, PF reduced the degree of swelling and Evans blue exudation in mice paws. Furthermore, PF dose-dependently reduced serum inflammatory mediator release in mice sensitized with ovalbumin for 48 h by inhibiting MC degranulation. Molecular docking study revealed that PF bound better with the α subunit of FcϵRI than with the β subunit. SPR revealed that PF had a strong affinity interaction with FcϵRI α subunit and the K_D value was (7.08 ± 0.97) e-6 M. Our findings revealed that PF inhibited anaphylactic responses in vivo and in vitro, and it can be considered a novel FcϵRI inhibitor for preventing MC-related allergic diseases.

Anti-inflammatory and immunoregulatory effects of paeoniflorin and total glucosides of paeony

As a Traditional Chinese Medicine, Paeonia lactiflora Pallas has been used to treat pain, inflammation and immune disorders for more than 1000 years in China. Total glycoside of paeony (TGP) is extracted from the dried root of Paeonia lactiflora Pallas. Paeoniflorin (Pae) is the major active component of TGP. Our research group has done a lot of work in the pharmacological mechanisms of Pae and found that Pae possessed extensive anti-inflammatory and immune regulatory effects. Pae could inhibit inflammation in the animal models of autoimmune diseases, such as experimental arthritis, psoriatic mice and experimental autoimmune encephalomyelitis, and so on. Pae modulates the functions and activation of immune cells, decreases inflammatory medium production, and restores abnormal signal pathway. Pae could balance the subsets of immune cells through inhibiting abnormal activated cell subsets and restoring regulatory cell subsets. Pae could regulate signaling pathways (GPCR pathway, MAPKs /NF-κB patway, PI3K /Akt /mTOR pathway, JAK2 /STAT3 pathway, TGFβ /Smads, and etc.). TGP is composed of Pae, hydroxyl-paeoniflorin, paeonin, albiflorin and benzoylpaeoniflorin etc. Pae accounts for more than 40% of TGP. Like Pae, TGP has anti-inflammatory and immune regulatory effects. TGP has been widely used to treat autoimmune diseases, including rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), psoriasis, allergic contact dermatitis, and etc. in China. Furthermore, TGP has some superior features with immune regulation, gentle effect, many indications and few adverse drug reactions. These findings suggest that TGP may be a promising anti-inflammatory and immune drug with soft regulation and has more superiority in the treatment of AIDs. Currently, TGP is used for the treatment of RA, SLE and other AIDs in more than 1000 hospitals in China, which obtained great social and economic benefits.

Scutellarin suppresses cartilage destruction in osteoarthritis mouse model by inhibiting the NF-κB and PI3K/AKT signaling pathways

Osteoarthritis (OA), a common and severe disease, is predominantly characterized by cartilage destruction, which results in the degeneration of joint surfaces. Nowadays, it is accepted that TNFα plays a critical role in OA. Scutellarin, the main bioactive flavonoid glycoside extracted form Erigeron breviscapus, has been reported to exert positive effects on anti-inflammatory reactions. However, the effect of scutellarin in OA is still unknown. In this study, we isolated and cultured primary murine chondrocytes, stimulating TNF-α, in the presence or absence of scutellarin treatment. We found that the inflammatory response stimulated by TNF-α was significantly inhibited by the addition of scutellarin. Moreover, we established OA mouse models induced by surgery. In this mouse model, both inflammatory reaction and cartilage degeneration were markedly inhibited by oral administration of scutellarin. Furthermore, the cellular mechanism underlying the protective effect of scutellarin in OA was clearly associated with the NF-κB and PI3K/AKT signaling pathways. Collectively, this study proposes scutellarin as a potential therapeutic to treat joint degenerative diseases, including OA.

A review for the anti-inflammatory effects of paeoniflorin in inflammatory disorders

Inflammatory disorders result from abnormal immune response and their incidence has increased recently. Thus, there is an urgent need to discover new treatments for inflammatory disorders. In recent years, the natural products contained in Chinese herbs have attracted much attention worldwide owing to their anti-inflammatory effects. Paeoniflorin (PF) is a bioactive compound purified from the Chinese herb Paeonia lactiflora and reports have recently emerged suggesting the great potential of P. lactiflora as an agent to counter inflammatory disorders. The anti-inflammatory effects of PF have been revealed by in vitro studies and in vivo animal experiments of different inflammatory disorders, including rheumatoid arthritis, inflammatory bowel disease, psoriasis, and asthma. This review systematically describes the recent progress of studies on the mechanism of PF and its therapeutic potential in inflammatory disorders.