Anti-inflammatory effect of paeoniflorin combined with baicalin in oral inflammatory diseases

Baicalin improves neurological outcomes in mice with ischemic stroke by inhibiting astrocyte activation and neuroinflammation

OBJECTIVE

The inflammatory response is integral to all stages of ischemic stroke. Unlike conventional reperfusion therapies, anti-inflammatory strategies offer a broader therapeutic window for treating ischemic stroke due to their capacity to attenuate inflammation. Astrocytes, once activated in ischemic conditions, significantly contribute to the production of inflammatory cytokines and exacerbate brain damage. While the neuroprotective effects of baicalin in post-stroke patients have been recognized, its role in modulating astrocyte activity and reducing inflammation remains under debate. This study aims to evaluate the impact of baicalin on astrocyte activation following ischemic stroke.

METHODS

A model of ischemia/reperfusion (I/R) injury was induced in wild-type mice through transient middle cerebral artery occlusion (tMCAO). Mice were randomized into groups receiving either baicalin or saline. The expression levels of inflammatory markers-interleukin (IL)-6, IL-1β, monocyte chemoattractant protein-1 (MCP-1), and tumor necrosis factor-alpha (TNF-α)-were quantified using enzyme-linked immunosorbent assay (ELISA). Additionally, western blot analysis was employed to assess glial fibrillary acidic protein (GFAP) expression.

RESULTS

Baicalin administration significantly mitigated neurological deficits in mice post-tMCAO. It reduced the activation of astrocytes and the production of pro-inflammatory cytokines such as IL-6, IL-1β, TNF-α, and MCP-1, observed both in vivo and in vitro. In vitro studies also indicated a suppression of NF-κB activation.

CONCLUSION

Baicalin effectively prevents ischemic brain damage by curtailing neuroinflammation and astrocyte activation. These findings advance the understanding of baicalin's mechanistic role in mitigating brain ischemia and support further investigation into its therapeutic potential.

Baicalin Decreases the LPS-Induced Intestine Inflammatory Responses by ROS/p-ERK/p-P38 Signal Pathways In Vivo and In Vitro

Background: This study aimed to investigate the role of ROS/MAPK signaling pathways and the effects of baicalin in LPS-induced inflammatory responses in mice and porcine intestinal epithelial cells (IPEC-J2). Methods: In vivo, 18 male C57BL/6J mice were randomly divided into three groups (n = 6): control, LPS (3.5 mg/kg LPS administered intraperitoneally [ip] on day 7), and baicalin (200 mg/kg orally for 7 days, with LPS ip on day 7). On day 8, mice were sacrificed, and jejunal tissues were collected for H&E staining. ROS levels in serum and cytokine protein expressions (TNF-α and IL-6) in the jejunum were measured via ELISA, while intestinal MAPK proteins were analyzed using Western blotting. In vitro, the study involved two experimental setups: NAC (a ROS scavenger) and baicalin. For the NAC experiment, IPEC-J2 cells were divided into three groups: control, LPS, and NAC. In the LPS group, cells were treated with LPS (40 μg/mL) for 1 h. In the NAC group, cells were pretreated with NAC prior to LPS exposure. For the baicalin experiment, IPEC-J2 cells were divided into five groups: control, LPS, and baicalin at low (10 μM), medium (20 μM), and high (40 μM) doses. Cells were pretreated with baicalin for 24 h before LPS exposure. ROS/LDH levels and cytokine expressions in the supernatant were determined via ELISA, and MAPK protein expressions were assessed using Western blotting. Results: In vivo, LPS-induced oxidative stress and inflammatory responses in the intestine, reduced the villus height-to-crypt ratio, and significantly increased protein expressions of p-ERK, p-P38, JNK, and p-JNK (p < 0.05). Baicalin treatment significantly inhibited serum ROS levels (p < 0.01), reduced jejunal cytokine expressions (TNF-α and IL-6, p < 0.05), improved intestinal structural damage, and decreased p-ERK, p-P38, and p-JNK protein expressions (p < 0.05). In vitro, NAC significantly reduced ROS levels (p < 0.01), cytokine expressions (TNF-α and IL-6), and MAPK activation (ERK, JNK, P38, and their phosphorylated forms, p < 0.05). Baicalin also significantly decreased ROS (p < 0.05), TNF-α (p < 0.05), IL-6 (p < 0.05), and MAPK protein expressions (ERK, p-ERK, and p-P38, p < 0.05). Molecular docking demonstrated that baicalin effectively bound to ERK and P38 proteins. Conclusions: Baicalin mitigated LPS-induced inflammatory responses via the ROS/p-ERK/p-P38 signaling pathway in vivo and in vitro.

Glycyrrhizin alleviates the toxicity of hydroxychloroquine in treating oral lichen planus by occupying heat shock protein 90 alpha

BACKGROUND

Oral lichen planus (OLP) is a common chronic inflammatory disease with the potential of malignant transformation. Hydroxychloroquine (HCQ), derived from quinine originating from Cinchona spp. bark, is a commonly prescribed off-label for OLP. However, it lacks robust evidence-based medicine practice, as well as theoretical guidance for its pharmacodynamic targets and for mitigating adverse reactions.

PURPOSE

To compare the efficacy of HCQ with first-line treatment prednisone for treating severe erosive OLP and to identify compatible phytomedicine that is reasonably available based on elucidating the molecular targets related to clinical benefits and adverse reactions.

METHODS

We performed a single-center, randomized, investigator-blinded, positive-controlled, non-inferiority trial. Patients who met the enrollment criteria were randomly allocated (1:1) to receive either HCQ or prednisone therapy for 4 weeks and follow-up for 3 months. The primary outcome measures included reductions in the erosion area and pain level. Potential targets of HCQ and associated toxic effects in treating OLP were identified through in silico analysis and validated through histological evaluation. Common hepatoprotective agents, including glycyrrhizin and total glucosides of peony, were analyzed for their potential targets. Then tri-molecular docking study was performed to screen available phytomedicine agent for alleviating adverse reaction of HCQ. Finally, in vitro experiments were performed to validate these targeted effects.

RESULTS

A total of 62 patients were enrolled from January 2021 to August 2023. After a 4-week treatment, there's no significant difference between patients receiving HCQ and PDN in the reduction of erosion area (median, 44 vs 58.5; HCQ - PDN difference: -11; 95 % CI, -39 to 13; p = 0.438) or pain level (median, 3 vs 3; HCQ - PDN difference: 0; 95 % CI, -1 to 1; p = 0.925). Heat shock protein 90 (HSP90) alpha and beta were identified as potential therapeutic targets of HCQ for treating OLP, while HSP90α is also associated with the adverse reactions of HCQ. The expressions of HSP90α and HSP90β in OLP tissue were significantly reduced compared to normal tissue. The phytomedicine glycyrrhizin was selected due to its specific interaction with the GLY-181 site of HSP90α, same as HCQ's toxic targets. HCQ exerted pro-proliferative and anti-inflammatory effects in vitro. And both HCQ and glycyrrhizin treatment restore the expression of HSP90β, while HCQ treatment also restored the expression of HSP90α.

CONCLUSIONS

HCQ was not inferior to prednisone for treating severe erosive OLP, suggesting it as an alternative to first-line treatment. Integrating phytopreparation glycyrrhizin into conventional HCQ treatment in OLP can help detoxify by occupying the HSP90α binding site.

Comparison between hangeshashinto and dexamethasone for IL-1α and β-defensin 1 production by human oral keratinocytes

OBJECTIVE

Human β-defensin 1 (hBD-1) is a antimicrobial peptide that is constantly secreted by oral tissues. Hangeshashinto (HST), a traditional Japanese medicine, has been reported to be effective against stomatitis. This study aimed to clarify the profile of HST by comparing the system of production of interleukin-1α (IL-1α) and hBD-1 in human oral mucosal epithelial cells with dexamethasone (DEX), a steroid used for the treatment of stomatitis.

METHODS

Human oral keratinocytes (HOK) were treated with HST, DEX, or HST components (baicalein, baicalin, berberine, and glycyrrhizin) for 24 h, and subsequently cultured for 24 h with or without Pam3CSK4 or lipopolysaccharide (LPS). The cell supernatants, total RNA, and intracellular proteins were collected, and changes in IL-1α and hBD-1 protein production and gene expression were evaluated using ELISA and RT-PCR. The phosphorylation of NF-kB and the cell proliferative ability of HOK were evaluated by western blotting and XTT assay, respectively.

RESULTS

DEX (0.01-10 μM) significantly suppressed IL-1α and hBD-1 production induced by either Pam3CSK4 or LPS, and also decreased cell growth. In contrast, HST inhibited Pam3CSK4- and LPS-induced IL-1α production at a concentration range of 12.5-100 μg/mL without affecting the cell proliferative capacity and hBD-1 production of HOK. Baicalein and baicalin, which are flavonoid ingredients of HST, showed anti-IL-1α production.

CONCLUSION

HST may be useful as a therapeutic agent for stomatitis and other inflammatory diseases of the oral cavity.

New Monoterpene Glycoside Paeoniflorin Derivatives as NO and IL-1β Inhibitors: Synthesis and Biological Evaluation

Several monoterpene glycoside compounds were extracted from Paeonia lactiflora Pall. Among them, paeoniflorin, a water-soluble monoterpene glycoside found in the root of Paeonia lactiflora Pall, exhibits excellent antioxidant pharmacological functions. Initially, Sc(CF3SO3)3 was employed as the catalyst for paeoniflorin's dehydration and rearrangement reactions with alcohols. Subsequently, structural modifications were performed on paeoniflorin through a series of responses, including acetylation, deacetylation, and debenzoylation, ultimately yielding 46 monoterpene glycoside derivatives. The potential inhibitory effects on the pro-inflammatory mediators interleukin-1 beta (IL-1β) and nitric oxide (NO) were assessed in vitro. The results revealed that compounds 29 and 31 demonstrated notable inhibition of NO production, while eight derivatives (3, 8, 18, 20, 21, 29, 34, and 40) displayed substantial inhibitory effects on the secretion of IL-1β. Computational research was also undertaken to investigate the binding affinity of the ligands with the target proteins. Interactions between the proteins and substrates were elucidated, and corresponding binding energies were calculated accordingly. The findings of this study could provide valuable insights into the design and development of novel anti-inflammatory agents with enhanced pharmacological properties.

Upregulation of IL-37 in epithelial cells: A potential new mechanism of T cell inhibition induced by tacrolimus

Oral lichen planus (OLP) is a chronic T cell-mediated mucocutaneous disease characterized by T cell infiltration at the connective tissue-epithelium interface. Traditionally, topical corticosteroids are used as the first-line drugs to treat OLP. However, long-term use of corticosteroids may lead to drug tolerance, secondary candidiasis, and autoimmune adrenal insufficiency. Although topical tacrolimus has often been recommended for short-term use in corticosteroid-refractory OLP, the precise role of tacrolimus in epithelial cells remains elusive. This study showed that tacrolimus could directly upregulate the expression of IL-37 in human gingival epithelial cells by promoting the TGF-βRI/Smad3 pathway independently of calcineurin inhibition and MAPKs. In contrast, dexamethasone, one of the corticosteroids, did not have the same effect. Moreover, IL-37 could inhibit the proliferation of activated T cells and the secretion of effector cytokines and alleviate epithelial cell apoptosis and death caused by activated T cells ina co-culturesystem. Furthermore, compared with healthy controls, IL-37 and p-Smad3 levels significantly increased in the oral mucosa affected by OLP, especially in the epithelium. IL-37 might have mediated a negative feedback mechanism to curb excessive inflammation in OLP. However, the expression of IL-37 was not associated with the infiltration of CD8+ T cells and Tregs in OLP, implying that IL-37 might mostly affect T cell activation rather than T cell differentiation and migration. Overall, this study discovered a potential novel mechanism by which tacrolimus might indirectly inhibit T cell-mediated immune damage by upregulating IL-37 in human gingival epithelial cells.

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.

Chitosan-based hydrogel wound dressing: From mechanism to applications, a review

As promising biomaterials, hydrogels are widely used in the medical engineering field, especially in wound repairing. Compared with traditional wound dressings, such as gauze and bandage, hydrogel could absorb and retain more water without dissolving or losing its three-dimensional structure, thus avoiding secondary injury and promoting wound healing. Chitosan and its derivatives have become hot research topics for hydrogel wound dressing production due to their unique molecular structure and diverse biological activities. In this review, the mechanism of wound healing was introduced systematically. The mechanism of action of chitosan in the first three stages of wound repair (hemostasis, antimicrobial properties and progranulation), the effect of chitosan deacetylation and the molecular weight on its performance are analyzed. Additionally, the recent progress in intelligent and drug-loaded chitosan-based hydrogels and the features and advantages of chitosan were discussed. Finally, the challenges and prospects for the future development of chitosan-based hydrogels were discussed.

Phytochemicals in the treatment of inflammation-associated diseases: the journey from preclinical trials to clinical practice

Advances in biomedical research have demonstrated that inflammation and its related diseases are the greatest threat to public health. Inflammatory action is the pathological response of the body towards the external stimuli such as infections, environmental factors, and autoimmune conditions to reduce tissue damage and improve patient comfort. However, when detrimental signal-transduction pathways are activated and inflammatory mediators are released over an extended period of time, the inflammatory process continues and a mild but persistent pro-inflammatory state may develop. Numerous degenerative disorders and chronic health issues including arthritis, diabetes, obesity, cancer, and cardiovascular diseases, among others, are associated with the emergence of a low-grade inflammatory state. Though, anti-inflammatory steroidal, as well as non-steroidal drugs, are extensively used against different inflammatory conditions, they show undesirable side effects upon long-term exposure, at times, leading to life-threatening consequences. Thus, drugs targeting chronic inflammation need to be developed to achieve better therapeutic management without or with a fewer side effects. Plants have been well known for their medicinal use for thousands of years due to their pharmacologically active phytochemicals belonging to diverse chemical classes with a number of these demonstrating potent anti-inflammatory activity. Some typical examples include colchicine (alkaloid), escin (triterpenoid saponin), capsaicin (methoxy phenol), bicyclol (lignan), borneol (monoterpene), and quercetin (flavonoid). These phytochemicals often act via regulating molecular mechanisms that synergize the anti-inflammatory pathways such as increased production of anti-inflammatory cytokines or interfere with the inflammatory pathways such as to reduce the production of pro-inflammatory cytokines and other modulators to improve the underlying pathological condition. This review describes the anti-inflammatory properties of a number of biologically active compounds derived from medicinal plants, and their mechanisms of pharmacological intervention to alleviate inflammation-associated diseases. The emphasis is given to information on anti-inflammatory phytochemicals that have been evaluated at the preclinical and clinical levels. Recent trends and gaps in the development of phytochemical-based anti-inflammatory drugs have also been included.

Efficacy identification and active compounds screening of topically administration of Scutellaria Radix in oral ulcer

Scutellaria Radix (SR) is often added to various preparations for the treatment of oral ulcer, but its own efficacy and active compounds are still unknown while topically administration for oral ulcer, bring obstacles in further research. We expected to demonstrate the anti-oral ulcer effect of SR and find out its hallmark compounds, so as to provide reference for its material basis research. In this study, in vivo and in vitro models were used to prove the efficacy of SR, and spectrum-effect analysis was used to figure out the active compounds. In oral ulcer rats, SR significantly reduced TNF-α and IL-8 level, raised IL-2 level in both serum and mucosa, enhanced SOD activity and decreased MDA level of serum, reduced inflammatory reaction and showed good therapeutic effect. As for in vitro models, SR increased the survival rates of H₂O₂ damaged HOK, inhibited the release of IL-1β and NO of LPS induced HOK and LPS induced RAW 264.7, demonstrating good efficacy on oral ulcer. Subsequently, fingerprints and cellular pharmacodynamic data for 18 batches of SR were acquired, and spectrum-effect analysis were carried out by grey correlation analysis (GRA), partial least squares regression (PLSR) and "spider-web" mode. Five potential compounds were screened out and validated by comparing with SR activity, and baicalin, baicalein, and wogonoside were finally identified as active compounds of SR. These results explained the material basis of SR in treating oral ulcer and provided a scientific evidence for the clinical application of SR in oral administration.

Preparation of triamcinolone acetonide-loaded chitosan/fucoidan hydrogel and its potential application as an oral mucosa patch

Oral inflammatory diseases (OIDs) are among the most common lesions in the oral cavity, affecting the quality of human life and even causing oral cancer. However, most of the current oral mucosa patches still have some limitations, particularly instant, poor mechanical strength and conformability, low adhesion to tissue, and foreign body sensation. Herein, triamcinolone acetonide (TA)-loaded chitosan/fucoidan (CF) composite hydrogels were prepared via chemical crosslinking. The macro/microscopic morphologies and (bio)physicochemical properties of composite hydrogels were investigated. Incorporating fucoidan in chitosan hydrogels greatly enhanced their swelling behavior, mechanical strength, and adhesion properties. Further, the addition of TA in CF hydrogels improved their elastic feature, inhibited inflammatory response, and promoted the formation of mature and well-organized collagen fibers. The developed composite hydrogels displayed not only good antibacterial properties but also good cytocompatibility and histocompatibility. Thus, the designed hydrogels allow the development of oral mucosa patches as a potential treatment for OIDs.

Inflammatory and immune-related factor Caspase 1 contributes to the development of oral lichen planus

OBJECTIVE

In this study, we aimed at underlying the potential regulatory mechanism and overall biological functions of caspase 1 (CASP1) in oral lichen planus (OLP).

DESIGN

Buccal mucosa tissue samples were gained from healthy subjects or patients diagnosed with OLP. Immunochemical staining was applied to detect CASP1 in OLP tissues. Lipopolysaccharide (LPS) was used to construct OLP in vitro models. Cell counting kit-8 (CCK-8) and flow cytometry assay were applied to detecte cell viability and apoptosis.

RESULTS

The upregulation of CASP1 in OLP has been identified through comprehensive bioinformatics analysis and verified in clinical samples. In OLP tissues, inflammation-related factors, including tumor necrosis factor alpha (TNF-α), interleukin (IL)-1β, IL-6, and IL-18, were elevated and positively correlated with CASP1. In HaCaT cells, LPS stimulation induced CASP1 upregulation, suppressed cell viability, facilitated cell apoptosis, and elevated the levels of TNF-α, IL-1β, IL-6, and IL-18; silencing of CASP1 attenuated LPS-induced damages to HaCaT cells. Pearson's correlation analysis identified that 45 immune-related genes were positively correlated with CASP1; these 45 genes were enriched in the immune system process, associated with combined immunodeficiency, and spleen-specific and CD56 + NK cell-specific. PPI network among CASP1 and correlated immune-related factors was constructed, and CASP1 was positively correlated with RAC2, CYBB, and ARHGDIB. In HaCaT cells, LPS stimulation induced RAC2, CYBB, and ARHGDIB expression, whereas knocking down CASP1 attenuated LPS-induced increases in RAC2, CYBB, and ARHGDIB.

CONCLUSION

CASP1 is upregulated in OLP tissues. Knockdown of CASP1 in HaCaT cells could protect HaCaT cells from LPS-induced inflammatory injury. Comprehensive bioinformatics indicates that the interaction of CASP1 with RAC2, CYBB, and ARHGDIB, might be the potential molecular mechanism.

Analysis and Construction of a Competitive Endogenous RNA Regulatory Network of Baicalin-Induced Apoptosis in Human Osteosarcoma Cells

BACKGROUND

Baicalin is an extract from the traditional Chinese herb Scutellaria baicalensis and has the potential to treat osteosarcoma (OS). However, the transcriptome-level mechanism of baicalin-mediated antitumor effects in OS has not yet been investigated. The aim of this study was to analyze the competitive endogenous RNA (ceRNA) regulatory network involved in baicalin-induced apoptosis of OS cells.

METHODS

In this study, CCK-8 and flow cytometry assays were used to detect the antitumor effects of baicalin on human OS MG63 cells. Furthermore, transcriptome sequencing was employed to establish the long noncoding RNA (lncRNA), microRNA (miRNA), and mRNA profiles.

RESULTS

Baicalin inhibited MG63 cell proliferation and induced apoptosis. Totals of 58 lncRNAs, 31 miRNAs, and 2136 mRNAs in the baicalin-treated MG63 cells were identified as differentially expressed RNAs compared to those in control cells. Of these, 2 lncRNAs, 3 miRNAs, and 18 mRNAs were included in the ceRNA regulatory network. The differentially expressed RNAs were confirmed by quantitative real-time PCR (qRT-PCR).

CONCLUSIONS

By identifying the ceRNA network, our results provide new information about the possible molecular basis of baicalin, which has potential applications in OS treatment.

Kuijieyuan Decoction Improved Intestinal Barrier Injury of Ulcerative Colitis by Affecting TLR4-Dependent PI3K/AKT/NF-κB Oxidative and Inflammatory Signaling and Gut Microbiota

Ethnopharmacological Relevance

In Traditional Chinese medicine (TCM) theory, ulcerative colitis (UC) is associated with damp-heat, blood stasis, and intestinal vascular ischemia. Kuijieyuan decoction (KD) is a traditional Chinese medicine based on the above theory and used clinically to alleviate UC injury.

Methods

The main components of KD were analyzed by using high-pressure liquid chromatography (HPLC) and confirmed by UPLC-MS/MS. A UC model was established in rats by using dextran sulfate sodium (DSS) and dead rats (caused by DSS) were excluded from the study. Forty-eight rats were divided into 6 groups, health control (CG), UC model (UG), sulfasalazine (SG), low-dose KD (LG), middle-dose KD (MG), and high-dose KD (HG) groups. UC damage was assessed by hematoxylin and eosin staining and scan electron microscopy. We measured Toll-like receptor 4 (TLR4), p-phosphatidylinositol 3-kinase (PI3K), PI3K, p-Protein kinase B (AKT), AKT, p-nuclear factor kappa B (NF-κB), NF-κB, oxidative stress marker (superoxidase dismutase (SOD), catalase (CAT), glutathione peroxidases (GPx), and malondialdehyde) and inflammatory markers (tumor necrosis factor α (TNFα), interleukin (IL)-1, IL-6 and IL-10) in UC tissues. Gut microbiota was analyzed through16S rRNA sequencing.

Results

The main components of KD consist of gallic acid, paeoniflorin, emodin, berberine, coptisine, palmatine, jatrorrhizine, baicalein and baicalin. The UC model was successfully established by causing intestinal barrier injury with the loss of intestinal villi and destructed mitochondria of intestinal epithelial cells. Both sulfasalazine and KD treatment repaired UC injury, reduced the levels of malondialdehyde, TNFα, IL-1, IL-6, TLR4, p-PI3K, p-AKT, and p-NF-κB, and increased the levels of SOD, GPx, CAT, and IL-10. KD showed a protective function for the UC model in a dose-dependent way. The serum levels of paeoniflorin and baicalin had a strong relationship with the levels of inflammatory and oxidative stress biomarkers. KD treatment increased the proportion of Alloprevotella, Treponema, Prevotellaceae, and Prevotella, and reduced the proportion of Escherichia_Shigella and Desulfovibrio in gut microbiota.

Conclusions

KD improved intestinal barrier injury of ulcerative colitis, antioxidant and anti-inflammatory properties by affecting TLR4-dependent PI3K/AKT/NF-κB signaling possibly through the combination of its main compounds, and improving gut microbiota.

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.