Differential effects of chlorogenic acid on various immunological parameters relevant to rheumatoid arthritis

The application prospects of sacha inchi (Plukenetia volubilis linneo) in rheumatoid arthritis

Sacha Inchi (Plukenetia volubilis L) (SI) is a traditional natural medicine from tropical rainforests of Amazon region in South America. As a raw material for edible oil, it has various pharmacological effects such as antioxidant, anti-inflammatory, hypolipidemia, and blood pressure lowering, which have attracted increasing attentions of pharmacists. This has prompted researchers to explore its pharmacological effects for potential applications in certain diseases. Among these, the study of its anti-inflammatory effects has become a particularly interesting topic, especially in rheumatoid arthritis (RA). RA is a systemic autoimmune disease, and often accompanied by chronic inflammatory reactions. Despite significant progress in its treatment, there is still an urgent need to find effective anti-RA drugs in regard to safety. This review summarizes the potential therapeutic effects of SI on RA by modulating gut microbiota, targeting inflammatory cells and pathways, and mimicking biologic antibody drugs, predicting the application prospects of SI in RA, and providing references for research aimed at using SI to treat RA.

A chlorogenic acid-conjugated nanomicelle attenuates disease severity in experimental arthritis

Rheumatoid arthritis (RA) is a systemic immune disorder marked by synovitis, bone damage, and cartilage erosion, leading to increased socio-economic burdens and reduced quality of life. Despite its unknown cause, advancements in understanding its pathophysiology have facilitated novel therapeutic approaches. Current treatments, including disease-modifying anti-rheumatic drugs (DMARDs) and biologics, often result in low efficacy and unnecessary side effects. To address the limitations of these drugs, carrier-based drug delivery systems, such as nanomicelles, have emerged as a promising solution. In this study, nanomicelles were synthesised utilizing PLGA (poly(lactic-co-glycolic acid)) as a backbone; this backbone is conjugated with chlorogenic acid (CGA), which is known for suppressing inflammation, and incorporates methotrexate (MTX), a model drug that is established for RA treatment. The nanomicelles were extensively characterized in terms of size, charge, drug loading, and drug-release behaviour. The in vivo assessment of MTX-PLGA-b-CGA nanomicelles in a collagen-induced arthritis model demonstrated a remarkable reduction in joint swelling, cartilage erosion, and disease severity. Furthermore, histological findings confirmed cartilage integrity and reduced expression of key pro-inflammatory markers, including receptor activator of nuclear factor kappa beta ligand (RANKL) and tumor necrosis factor (TNF-α). The approach based on the MTX-PLGA-b-CGA nanomicelles presents a biocompatible and potentially effective therapeutic strategy for management of the severity and progression of RA, providing a hopeful alternative for RA treatment.

Chlorogenic acid co-administration alleviates cisplatin-induced peripheral neuropathy in rats

BACKGROUND

Chemotherapy-induced peripheral neuropathy (CIPN) is still an unresolved problem in cisplatin (CIS) use.

OBJECTIVES

This study investigates possible anti-neuropathic effect of chlorogenic acid (CGA) against CIS-induced CIPN in rats while also investigating the contribution of nitric oxide (NO) to this phenomenon.

METHODS

Initially, CGA (250-1000 μM) was tested by MTT assay on primary DRG neurons. Subsequently, CIPN was induced in Sprague-Dawley rats by 3 mg/kg intraperitoneal injections of CIS once/week for 5 weeks. CGA (100 mg/kg) was co-administered with CIS, both alone and in combination with l-arginine (LARG) or l-nitro-arginine-methyl-ester (LNAME), to elucidate the contribution of nitrergic system to anti-neuropathic effects. Mechanical allodynia, thermal hyperalgesia, and cold plate tests were performed to test CIPN. Rotarod, footprint analysis, and activitymeter were used to evaluate motor coordination and performance. Tumor necrosis factor alpha (TNF-α) was measured as a marker of inflammation. Histological evaluations of DRG and sciatic nerves (SNs) were performed utilizing toluidine blue staining. Two-way analysis of variance and Kruskal-Wallis following Tukey's test were used as statistical analysis.

RESULTS

Higher concentration of CGA (1000 μM) exhibited protective effect against in vitro neurotoxicity. Neither LARG nor LNAME exerted significant change in this effect. Co-administration of CGA alleviated histological abnormalities and neuropathic effects induced by CIS. Ameliorative effect of CGA was not changed in mechanical allodynia but attenuated in cold allodynia, and motor activity/coordination tests by LARG and LNAME. Neuropathic effects of CIS remained unchanged with LARG and LNAME in behavioral experiments.

CONCLUSION

The study identified CGA as candidate agent in mitigating CIPN. NO seems to play a modulatory role in this effect.

Osteogenic mechanism of chlorogenic acid and its application in clinical practice

Natural polyphenols may have a role in counteracting oxidative stress, which is associated with aging and several bone-related diseases. Chlorogenic acid (CGA) is a naturally occurring polyphenolic compound formed by the esterification of caffeic and quininic acids with osteogenic, antioxidant, and anti-inflammatory properties. This review discusses the potential of CGA to enhance osteogenesis by increasing the osteogenic capacity of mesenchymal stem cells (MSCs), osteoblast survival, proliferation, differentiation, and mineralization, as well as its ability to attenuate osteoclastogenesis by enhancing osteoclast apoptosis and impeding osteoclast regeneration. CGA can be involved in bone remodeling by acting directly on pro-osteoclasts/osteoblasts or indirectly on osteoclasts by activating the nuclear factor kB (RANK)/RANK ligand (RANKL)/acting osteoprotegerin (OPG) system. Finally, we provide perspectives for using CGA to treat bone diseases.

Anti-Atherosclerotic Properties of Aronia melanocarpa Extracts Influenced by Their Chemical Composition Associated with the Ripening Stage of the Berries

The high content of bioactive compounds in Aronia melanocarpa fruit offers health benefits. In this study, the anti-atherosclerotic effect of Aronia extracts was assessed. The impact on the level of adhesion molecules and the inflammatory response of human umbilical vein endothelial cells (HUVECs) was shown in relation to the chemical composition and the stage of ripening of the fruits. Samples were collected between May (green, unripe) and October (red, overripe) on two farms in Poland, which differed in climate. The content of chlorogenic acids, anthocyanins, and carbohydrates in the extracts was determined using HPLC-DAD/RI. The surface expression of ICAM-1 and VCAM-1 in HUVECs was determined by flow cytometry. The mRNA levels of VCAM-1, ICAM-1, IL-6, and MCP-1 were assessed using the quantitative real-time PCR method. The farms' geographical location was associated with the quantity of active compounds in berries and their anti-atherosclerotic properties. Confirmed activity for green fruits was linked to their high chlorogenic acid content.

Chlorogenic Acid: A Systematic Review on the Biological Functions, Mechanistic Actions, and Therapeutic Potentials

Chlorogenic acid (CGA) is a type of polyphenol compound found in rich concentrations in many plants such as green coffee beans. As an active natural substance, CGA exerts diverse therapeutic effects in response to a variety of pathological challenges, particularly conditions associated with chronic metabolic diseases and age-related disorders. It shows multidimensional functions, including neuroprotection for neurodegenerative disorders and diabetic peripheral neuropathy, anti-inflammation, anti-oxidation, anti-pathogens, mitigation of cardiovascular disorders, skin diseases, diabetes mellitus, liver and kidney injuries, and anti-tumor activities. Mechanistically, its integrative functions act through the modulation of anti-inflammation/oxidation and metabolic homeostasis. It can thwart inflammatory constituents at multiple levels such as curtailing NF-kB pathways to neutralize primitive inflammatory factors, hindering inflammatory propagation, and alleviating inflammation-related tissue injury. It concurrently raises pivotal antioxidants by activating the Nrf2 pathway, thus scavenging excessive cellular free radicals. It elevates AMPK pathways for the maintenance and restoration of metabolic homeostasis of glucose and lipids. Additionally, CGA shows functions of neuromodulation by targeting neuroreceptors and ion channels. In this review, we systematically recapitulate CGA's pharmacological activities, medicinal properties, and mechanistic actions as a potential therapeutic agent. Further studies for defining its specific targeting molecules, improving its bioavailability, and validating its clinical efficacy are required to corroborate the therapeutic effects of CGA.

Recent Updates on the Therapeutics Benefits, Clinical Trials, and Novel Delivery Systems of Chlorogenic Acid for the Management of Diseases with a Special Emphasis on Ulcerative Colitis

Ulcerative colitis (UC) is a multifactorial disorder of the large intestine, especially the colon, and has become a challenge globally. Allopathic medicines are primarily available for the treatment and prevention of UC. However, their uses are limited due to several side effects. Hence, an alternative therapy is of utmost importance in this regard. Herbal medicines are considered safe and effective for managing human health problems. Chlorogenic acid (CGA), the herbal-derived bioactive, has been reported for pharmacological effects like antiinflammatory, immunomodulatory, antimicrobial, hepatoprotective, antioxidant, anticancer, etc. This review aims to understand the antiinflammatory and chemopreventive potential of CGA against UC. Apart from its excellent therapeutic potential, it has been associated with low absorption and poor oral bioavailability. In this context, colon-specific novel drug delivery systems (NDDS)are pioneering to overcome these problems. The pertinent literature was compiled from a thorough search on various databases such as ScienceDirect, PubMed, Google Scholar, etc., utilizing numerous keywords, including ulcerative colitis, herbal drugs, CGA, pharmacological activities, mechanism of actions, nanoformulations, clinical updates, and many others. Relevant publications accessed till now were chosen, whereas non-relevant papers, unpublished data, and non-original articles were excluded. The present review comprises recent studies on pharmacological activities and novel drug delivery systems of CGA for managing UC. In addition, the clinical trials of CGA against UC have been discussed.

Xuelian injection ameliorates complete Freund's adjuvant-induced acute arthritis in rats via inhibiting TLR4 signaling

Background

Xuelian injection (XI), a classic preparation extracted from Saussureae Involucratae Herba, has been clinically used to manage rheumatoid arthritis (RA) for nearly twenty years in China. However, the underlying anti-RA mechanism of XI remains unclear. In this study, complete Freund's adjuvant (CFA)-induced acute arthritic model was used to examine the anti-RA effects of XI in vivo. The molecular mechanisms of this action were further investigated using lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages.

Methods

XI and XI freeze dried powder were characterized by UPLC analysis. CD68 and TLR4 expression in the ankle joints was measured by immunohistochemistry. The secretion of inflammatory mediators was detected by ELISA. The expression levels of TLR4 involved components were measured by Western blotting. The localization of transcription factors was measured by immunofluorescence assay.

Results

XI treatment ameliorated arthritic symptoms induced by CFA in the ankle joints of rats. The serum levels of inflammatory mediators, including TNF-α, MCP-1, and Rantes were decreased by XI treatment. The elevation of CD68 and TLR4 levels in ankle joints caused by CFA was suppressed by XI treatment. Moreover, XI treatment inhibited the secretion of nitric oxide and prostaglandin E2 in LPS-treated RAW264.7 macrophages. The expression of their enzymes iNOS and COX-2 was also decreased after XI treatment. The production of inflammatory mediators, including TNF-α, IL-6, IL-1β, MCP-1, MIP-1α, and Rantes was reduced by XI treatment in LPS-stimulated RAW264.7 cells. The phosphorylation of p38, JNK, ERK, TBK1, IKKα/β, IκB, p65, c-Jun, and IRF3 was reduced after XI treatment. Additionally, the expression levels of nuclear proteins of p65, c-Jun, and IRF3 were inhibited by XI treatment.

Conclusions

Taken together, XI possesses potential anti-RA effect and the underlying mechanism may be closely associated with the inhibition of TLR4 signaling. Our findings provide further pharmacological justifications for the clinical use of XI in RA treatment.

Impact of Chlorogenic Acid on Peripheral Blood Mononuclear Cell Proliferation, Oxidative Stress, and Inflammatory Responses in Racehorses during Exercise

Green coffee extract is currently of great interest to researchers due to its high concentration of chlorogenic acid (CGA) and its potential health benefits. CGA constitutes 6 to 10% of the dry weight of the extract and, due to its anti-inflammatory properties, is a promising natural supplement and agent with therapeutic applications. The purpose of our study was to discover the effects of CGA on peripheral blood mononuclear cell proliferation, and the production of pro- and anti-inflammatory cytokines as well as reactive oxidative species (ROS) in horses during exercise. According to the findings, CGA can affect the proliferation of T helper cells. In addition, at a dose of 50 g/mL, CGA increased the activation of CD4+FoxP3+ and CD8+FoxP3+ regulatory cells. Physical activity decreases ROS production in CD5+ monocytes, but this effect depends on the concentration of CGA, and the effect of exercise on oxidative stress was lower in CD14+ than in CD5+ cells. Regardless of CGA content, CGA significantly increased the release of the anti-inflammatory cytokine IL-10. Moreover, the production of IL-17 was greater in cells treated with 50 g/mL of CGA from beginners compared to the control and advanced groups of horses. Our findings suggest that CGA may have immune-enhancing properties. This opens new avenues of research into the mechanisms of action of CGA and possible applications in prevention and health promotion in sport animals.

Mechanisms of action of coffee bioactive compounds - a key to unveil the coffee paradox

The knowledge of the relationship between the chemical structure of food components with their mechanisms of action is crucial for the understanding of diet health benefits. This review relates the chemical variability present in coffee beverages with the mechanisms involved in key physiological events, supporting coffee as a polyvalent functional food. Coffee intake has been related with several health-promoting properties such as neuroprotective (caffeine, chlorogenic acids and melanoidins), anti-inflammatory (caffeine, chlorogenic acids, melanoidins, diterpenes), microbiota modulation (polysaccharides, melanoidins, chlorogenic acids), immunostimulatory (polysaccharides), antidiabetic (trigonelline, chlorogenic acids), antihypertensive (chlorogenic acids) and hypocholesterolemic (polysaccharides, chlorogenic acids, lipids). Nevertheless, caffeine and diterpenes are coffee components with ambivalent effects on health. Additionally, a large range of potentially harmful compounds, including acrylamide, hydroxymethylfurfural, furan, and advanced glycation end products, are formed during the roasting of coffee and are present in the beverages. However, coffee beverages are part of the daily human dietary healthy habits, configuring a coffee paradox.

Epimedii Herba: An ancient Chinese herbal medicine in the prevention and treatment of rheumatoid arthritis

Rheumatoid arthritis (RA) is a chronic, progressive inflammatory and systemic autoimmune disease resulting in severe joint destruction, lifelong suffering and considerable disability. Diverse prescriptions of traditional Chinese medicine (TCM) containing Epimedii Herba (EH) achieve greatly curative effects against RA. The present review aims to systemically summarize the therapeutic effect, pharmacological mechanism, bioavailability and safety assessment of EH to provide a novel insight for subsequent studies. The search terms included were "Epimedii Herba", "yinyanghuo", "arthritis, rheumatoid" and "Rheumatoid Arthritis", and relevant literatures were collected on the database such as Google Scholar, Pubmed, Web of Science and CNKI. In this review, 15 compounds from EH for the treatment of RA were summarized from the aspects of anti-inflammatory, immunoregulatory, cartilage and bone protective, antiangiogenic and antioxidant activities. Although EH has been frequently used to treat RA in clinical practice, studies on mechanisms of these activities are still scarce. Various compounds of EH have the multifunctional traits in the treatment of RA, so EH may be a great complementary medicine option and it is necessary to pay more attention to further research and development.

Chlorogenic Acid Relieves the Lupus Erythematosus-like Skin Lesions and Arthritis in MRL/lpr Mice

Chlorogenic acid (CGA) is a phenylpropyl substance synthesized through the shikimic acid pathway. In addition to its anti-tumor, anti-inflammatory, and antioxidant abilities, CGA also has immunomodulatory effects. The aim of the present study is to investigate the therapeutic effects of CGA on the skin damage and arthritis caused by systemic lupus erythematosus (SLE) in an MRL/lpr mouse model. In the SLE model, female MRL/lpr mice at the age of 10 weeks old were treated with CGA daily or cyclophosphamide (CTX) weekly via intraperitoneal injection for three months. After treatment, CGA can significantly alleviate the skin and mucous membrane damage caused by SLE and has a certain improvement effect on arthritis. CGA could inhibit dsDNA expression to a certain extent but has no obvious regulation on ANA concentration. The ELISA and BioMAP results indicated that CGA might play an anti-inflammatory role by down-regulating the interleukin (IL)-17 level. In conclusion, our study demonstrates that CGA can alleviate multiorgan damage in MRL/lpr mice by reducing IL-17.

Effects of Caffeine and 5-Caffeoylquinic Acid on Blood Cell In Vitro Cytokine Production in Response to Lipopolysaccharide Stimulation

Previous in vitro studies the have suggested anti-inflammatory properties of caffeine. Coffee is also rich in phenolic acids with several potential health benefits (chlorogenic acids), mainly 5-caffeoylquinic acid (5-CQA). The aim of the present study was to determine the effect of caffeine and 5-CQA, using concentrations comparable to typical human consumption, on LPS-induced cytokine production in whole blood in vitro cultures. Whole blood samples (n = 10) were stimulated for 24 h with LPS in the presence of caffeine or 5-CQA. The concentrations of various cytokines, malondialdehyde (MDA) and adenosine-3′,5′-cyclic monophosphate (cAMP) were determined in the culture media. Significant effects of caffeine were found only for the stimulated production of TNF-α (p = 0.014) and cAMP (p = 0.001). However, only the highest caffeine concentration (50 μM) induced lower TNF-α (p = 0.016) and higher cAMP (p = 0.006) levels in comparison to the control. The 5-CQA only influenced the stimulated production of IL-6 (p = 0.002), with lower values for the highest 5-CQA concentrations (2 μM: p = 0.012; 20 μM: p < 0.001). Neither caffeine (p = 0.227) nor 5-CQA (p = 0.259) influenced MDA concentrations. In conclusion, both caffeine and 5-CQA exerted limited in vitro anti-inflammatory effects. For caffeine, these effects were attained with high physiological concentrations. However, for 5-CQA, supraphysiological concentrations were needed.

Association Between Rheumatoid Arthritis and Risk of Parkinson's Disease: A Meta-Analysis and Systematic Review

Background

Rheumatoid arthritis (RA) and Parkinson's disease (PD) are two common chronic diseases worldwide, and any potential link between the two would significantly impact public health practice. Considering the current inconsistent evidence, we conducted a meta-analysis and systematic review to examine the risk of PD in patients with RA.

Methods

Two investigators (DL and XH) conducted a comprehensive search of PubMed, Embase, and Web of Science using medical subject headings terms combined with free words to identify relevant papers published from inception through December 31, 2021. All studies that explored the relationship between RA and PD were included for quantitative analysis and qualitative review. Random- and fixed-effects models were used to pool the risk ratios (RRs) of PD in patients with RA. The Newcastle-Ottawa scale was used to assess the quality of included studies. This study followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA 2020) guideline.

Results

Four population-based studies involving 353,246 patients and one Mendelian randomized study were included in our study. The pooled result showed a significantly reduced risk of PD in patients with RA than in the general population (RR = 0.74, 95% CI: 0.56-0.98, P = 0.034). No apparent effects of gender, age, region, follow-up time, or study design on PD risk were observed. Sensitivity analysis showed that pooled results were relatively stable, and no publication bias was detected. The Mendelian randomization study indicated a significant inverse association between RA and PD (genetic correlation: −0.10, P = 0.0033) and that each one standard deviation increase in the risk of RA was significantly associated with a lower risk of PD. Of note, the current study is limited by the relatively small number of included studies and unmeasured confounding factors, especially for RA-related anti-inflammatory agents.

Conclusions

This study supports that people with RA had a lower PD risk than those without RA. Further studies are needed to explore the underlying molecular mechanisms of the interaction between the two diseases.

DNA Methylation of T Lymphocytes as a Therapeutic Target: Implications for Rheumatoid Arthritis Etiology

Rheumatoid arthritis (RA) is an autoimmune disease that can cause joint damage and disability. Epigenetic variation, especially DNA methylation, has been shown to be involved in almost all the stages of the pathology of RA, from autoantibody production to various self-effector T cells and the defects of protective T cells that can lead to chronic inflammation and erosion of bones and joints. Given the critical role of T cells in the pathology of RA, the regulatory functions of DNA methylation in T cell biology remain unclear. In this review, we elaborate on the relationship between RA pathogenesis and DNA methylation in the context of different T cell populations. We summarize the relevant methylation events in T cell development, differentiation, and T cell-related genes in disease prediction and drug efficacy. Understanding the epigenetic regulation of T cells has the potential to profoundly translate preclinical results into clinical practice and provide a framework for the development of novel, individualized RA therapeutics.

Lamiaceae in Mexican Species, a Great but Scarcely Explored Source of Secondary Metabolites with Potential Pharmacological Effects in Pain Relief

The search for molecules that contribute to the relief of pain is a field of research in constant development. Lamiaceae is one of the most recognized families world-wide for its use in traditional medicine to treat diseases that include pain and inflammation. Mexico can be considered one of the most important centers of diversification, and due to the high endemism of this family, it is crucial for the in situ conservation of this family. Information about the most common genera and species found in this country and their uses in folk medicine are scarcely reported in the literature. After an extensive inspection in bibliographic databases, mainly Sciencedirect, Pubmed and Springer, almost 1200 articles describing aspects of Lamiaceae were found; however, 217 articles were selected because they recognize the Mexican genera and species with antinociceptive and/or anti-inflammatory potential to relieve pain, such as Salvia and Agastache. The bioactive constituents of these genera were mainly terpenes (volatile and non-volatile) and phenolic compounds such as flavonoids (glycosides and aglycone). The aim of this review is to analyze important aspects of Mexican genera of Lamiaceae, scarcely explored as a potential source of secondary metabolites responsible for the analgesic and anti-inflammatory properties of these species. In addition, we point out the possible mechanisms of action involved and the modulatory pathways investigated in different experimental models. As a result of this review, it is important to mention that scarce information has been reported regarding species of this family from Mexican genera. In fact, despite Calosphace being one of the largest subgenera of Salvia in the world, found mainly in Mexico, it has been barely investigated regarding its potential biological activities and recognized bioactive constituents. The scientific evidence regarding the different bioactive constituents found in species of Lamiaceae demonstrates that several species require further investigation in preclinical studies, and of course also in controlled clinical trials evaluating the efficacy and safety of these natural products to support their therapeutic potential in pain relief and/or inflammation, among other health conditions. Since Mexico is one of the most important centers of diversification, and due to the high endemism of species of this family, it is crucial their rescue, in situ conservation, and investigation of their health benefits.

Pharmacological Insights into Halophyte Bioactive Extract Action on Anti-Inflammatory, Pain Relief and Antibiotics-Type Mechanisms

The pharmacological activities in bioactive plant extracts play an increasing role in sustainable resources for valorization and biomedical applications. Bioactive phytochemicals, including natural compounds, secondary metabolites and their derivatives, have attracted significant attention for use in both medicinal products and cosmetic products. Our review highlights the pharmacological mode-of-action and current biomedical applications of key bioactive compounds applied as anti-inflammatory, bactericidal with antibiotics effects, and pain relief purposes in controlled clinical studies or preclinical studies. In this systematic review, the availability of bioactive compounds from several salt-tolerant plant species, mainly focusing on the three promising species Aster tripolium, Crithmum maritimum and Salicornia europaea, are summarized and discussed. All three of them have been widely used in natural folk medicines and are now in the focus for future nutraceutical and pharmacological applications.

Chlorogenic Acid Promotes Autophagy and Alleviates Salmonella Typhimurium Infection Through the lncRNAGAS5/miR-23a/PTEN Axis and the p38 MAPK Pathway

Background

Salmonella typhimurium (ST) causes several intestinal diseases. Polyphenols including chlorogenic acid (CGA) inhibit pathogenesis.

Objective

This study aimed to investigate the mechanisms of CGA in ST infection.

Methods

The intestinal pathological changes and survival rate of ST-infected mice were measured to verify the protection of CGA on ST infection. The antibacterial effects of CGA in vitro on the invasion to intestinal epithelial cells and autophagy was evaluated. The relationships among GAS5, miR-23a, and PTEN were verified. Expression of inflammation- and autophagy-related proteins was detected.

Results

CGA treatment alleviated pathological damage, improved the secretion disturbance of intestinal cytokines caused by ST infection, and reduced the mortality of mice. Intestinal GAS5 was upregulated after CGA treatment. LncRNA GAS5 competitively bound to miR-23a to upregulate PTEN and inhibit the p38 MAPK pathway. CGA regulated the p38 MAPK pathway through lncRNA GAS5/miR-23a/PTEN axis to promote autophagy in ST infection. The functional rescue experiments of miR-23a and PTEN further identified these effects.

Conclusion

CGA promotes autophagy and inhibits ST infection through the GAS5/miR-23a/PTEN axis and the p38 MAPK pathway.

Pharmacologic Overview of Chlorogenic Acid and its Metabolites in Chronic Pain and Inflammation

BACKGROUND

Natural phenolic compounds in medicinal herbs and dietary plants are antioxidants which play therapeutic or preventive roles in different pathological situations, such as oxidative stress and inflammation. One of the most studied phenolic compounds in the last decade is chlorogenic acid (CGA), which is a potent antioxidant found in certain foods and drinks.

OBJECTIVE

This review focuses on the anti-inflammatory and antinociceptive bioactivities of CGA, and the putative mechanisms of action are described. Ethnopharmacological reports related to these bioactivities are also reviewed.

MATERIALS AND METHODS

An electronic literature search was conducted by authors up to October 2019. Original articles were selected.

RESULTS

CGA has been shown to reduce inflammation and modulate inflammatory and neuropathic pain in animal models.

CONCLUSION

The consensus of the literature search was that systemic CGA may facilitate pain management via bolstering antioxidant defenses against inflammatory insults.

Chlorogenic Acid Alleviates Allergic Inflammatory Responses Through Regulating Th1/Th2 Balance in Ovalbumin-Induced Allergic Rhinitis Mice

BACKGROUND Allergic rhinitis (AR) is a prevalent atopic disorder caused by immune imbalance. Chlorogenic acid (CGA) has antibacterial, antiviral, antioxidative and immunoregulatory effects, but its role in anaphylactic disease remains unclear. The current study aimed to investigate the function of CGA in AR. MATERIAL AND METHODS AR mice models were induced with ovalbumin (OVA) by orally administrating the mice with 50 mg/kg (L-CGA), 100 mg/kg (M-CGA), or 200 mg/kg (H-CGA) of CGA. The number of nasal rubbings and sneezes was recorded. Afterward, the mice were sacrificed for the collection of blood, nasal lavage fluid (NALF), and nasal tissues. The cells in NALF were counted by hemocytometer and stained by Diff-Quick. Nasal mucosa was observed by H&E staining. ELISA testing was conducted for detecting the levels of anti-OVA antibodies and Th1/Th2-related cytokine. Quantitative real-time polymerase chain reaction experiments were conducted to determine mRNA expressions of Th1/Th2-related cytokines. RESULTS In the OVA-induced AR mice, CGA treatment reduced nasal rubbing and sneezing, and also suppressed the number of total cells, eosinophils, neutrophils, lymphocytes, macrophages, and epithelial cells in NALF. OVA-induced up-regulation of nasal mucosa thickness was inhibited by CGA, and the effects of OVA on IgE, IgG1, and IgG2a were reversed by CGA. The regulatory effects of OVA on mRNA expressions and levels of Th1/Th2-related cytokines were abolished by CGA treatment in AR mice. CONCLUSIONS CGA can alleviate allergic inflammatory responses through regulating Th1/Th2 balance in OVA-induced allergic rhinitis mice.

The sources and mechanisms of bioactive ingredients in coffee

Coffee bioactive components include caffeine, chlorogenic acids (CGAs), trigonelline, tryptophan alkaloids, diterpenes and other secondary metabolites. During roasting, coffee metabolites undergo complex Maillard reactions, producing melanoidins and other degradation products, the most controversial among which is acrylamide, an ingredient widely found in baked food and listed as a second class carcinogen. Green and roasted coffee ingredients have good biological activities for the prevention of cardiovascular disease, and antibacterial, anti-diabetic, neuroprotection, and anti-cancer activities. To better understand the relationship between coffee ingredients and human health, and to effectively use the active ingredients, it is essential to understand the sources of coffee active ingredients and their mechanisms of action in the organism. This paper systematizes the available information and provides a critical overview of the sources of coffee active ingredients and the mechanisms of action in vivo or in vitro, and their combined effects on common human diseases.

Chlorogenic Acid Inhibits BAFF Expression in Collagen-Induced Arthritis and Human Synoviocyte MH7A Cells by Modulating the Activation of the NF-κB Signaling Pathway

B cell activating factor (BAFF), a member of the tumor necrosis factor (TNF) family, plays a critical role in the pathogenesis and progression of rheumatoid arthritis (RA). Chlorogenic acid (CGA) is a phenolic compound and exerts antiarthritic activities in arthritis. However, it is not clear whether the anti-inflammatory property of CGA is associated with the regulation of BAFF expression. In this study, we found that treatment of the collagen-induced arthritis (CIA) mice with CGA significantly attenuated arthritis progression and markedly inhibited BAFF production in serum as well as the production of serum TNF-α. Furthermore, CGA inhibits TNF-α-induced BAFF expression in a dose-dependent manner and apoptosis in MH7A cells. Mechanistically, we found the DNA-binding site for the transcription factor NF-κB in the BAFF promoter region is required for this regulation. Moreover, CGA reduces the DNA-binding activity of NF-κB to the BAFF promoter region and suppresses BAFF expression through the NF-κB pathway in TNF-α-stimulated MH7A cells. These results suggest that CGA may serve as a novel therapeutic agent for the treatment of RA by targeting BAFF.

Yerba mate aqueous extract improves the oxidative and inflammatory states of rats with adjuvant-induced arthritis

Healthy and adjuvant-induced arthritic rats were treated for 23 days with daily doses of 400 and 800 mg kg⁻¹Ilex paraguariensisextract.

Mansoa alliacea extract presents antinociceptive effect in a chronic inflammatory pain model in mice through opioid mechanisms

In some chronic disorders, as in arthritis, the inflammatory pain persists beyond the inflammation control becoming pathological. Its treatment shows limited efficacy and adverse effects which compromises patients' quality of life. Mansoa alliacea, known as 'cipo alho', is popularly used as analgesic and others species of this genus show anti-inflammatory actions. We investigated the anti-inflammatory and antinociceptive potential of M. alliacea extract in an inflammatory pain model which presents inflammatory characteristics similar to those caused by arthritis, through of the intraplantar injection of complete Freund's adjuvant (CFA) in mice. The extract chromatographic analysis revealed the presence of ρ-coumaric, ferulic and chlorogenic acids, luteolin, and apigenin. The treatment with M. alliacea prevented and reversed the CFA-induced mechanical allodynia with maximum inhibition (I_max) of 100% and 90 ± 10%, respectively. The co-administration of M. alliacea extract plus morphine enhanced the anti-allodynic effect with I_max of 100%. The M. alliacea extract also reverted the CFA-induced thermal hyperalgesia with I_max of 3.6 times greater compared to the vehicle and reduced the thermal threshold under physiological conditions. However, M. alliacea extract did not reduce the CFA-induced edema and myeloperoxidase activity. Additionally, non-selective and δ-selective opioid receptor antagonists, but not κ-opioid, prevented extract anti-allodynic effect with I_max of 98 ± 2% and 93 ± 2%, respectively. Moreover, M. alliacea extract did not induce adverse effects commonly caused by opioids and other analgesic drugs, at least in the tested pharmacological doses after the acute treatment. M. alliacea extract presents antinociceptive activity in an inflammatory pain model, which presents inflammatory characteristics similar to those arthritis-induced, without causing adverse effects in tested pharmacological doses. These effects seem to be mediated mainly via δ-opioid receptors.

Comparative Studies of Different Extracts from Eucommia ulmoides Oliv. against Rheumatoid Arthritis in CIA Rats

To compare efficacy of different extracts from Eucommia ulmoides Oliv. with both immune inflammation and joint destruction in collagen induced arthritis (CIA) rat model. Rats were divided into normal group (Nor), control group (CIA), TG group (treated with tripterygium glycoside), E70 group (treated with 70% ethanol extract from Eucommia ulmoides Oliv.), EA group (treated with ethyl acetate fraction from E70), and EN group (treated with n-butyl alcohol fraction from E70). All extracts from Eucommia ulmoides Oliv. could significantly inhibit ankle swelling, pathological manifestations, and cytokine levels in serum and spleen, by using foot volume measurement, H&E staining, ELISA, and RT-QPCR methods, respectively. All extracts could significantly inhibit rough joint surface and marginal osteophytes, improve RANKL/OPG ratio, and decrease MMP-9 expression, by using micro-CT and immunohistochemical staining. The activation of IKK/NF-κB signaling pathway was also inhibited by all extracts. In addition, ethyl acetate fraction from E70 presented better effect on RANKL/OPG system. This study identified effective extracts from Eucommia ulmoides Oliv. relieving immune inflammation and maintaining structural integrity of joints in CIA rats.

The potential effects of chlorogenic acid, the main phenolic components in coffee, on health: a comprehensive review of the literature

Chlorogenic acid (CGA), an important biologically active dietary polyphenol, is produced by certain plant species and is a major component of coffee. Reduction in the risk of a variety of diseases following CGA consumption has been mentioned in recent basic and clinical research studies. This systematic review discusses in vivo animal and human studies of the physiological and biochemical effects of chlorogenic acids (CGAs) on biomarkers of chronic disease. We searched PubMed, Embase, Amed and Scopus using the following search terms: ("chlorogenic acid" OR "green coffee bean extract") AND (human OR animal) (last performed on April 1st, 2015) for relevant literature on the in vivo effects of CGAs in animal and human models, including clinical trials on cardiovascular, metabolic, cancerogenic, neurological and other functions. After exclusion of editorials and letters, uncontrolled observations, duplicate and not relevant publications the remaining 94 studies have been reviewed. The biological properties of CGA in addition to its antioxidant and anti-inflammatory effects have recently been reported. It is postulated that CGA is able to exert pivotal roles on glucose and lipid metabolism regulation and on the related disorders, e.g. diabetes, cardiovascular disease (CVD), obesity, cancer, and hepatic steatosis. The wide range of potential health benefits of CGA, including its anti-diabetic, anti-carcinogenic, anti-inflammatory and anti-obesity impacts, may provide a non-pharmacological and non-invasive approach for treatment or prevention of some chronic diseases. In this study, the effects of CGAs on different aspects of health by reviewing the related literatures have been discussed.

The Extract of Chrysanthemum zawadskii var. latilobum Ameliorates Collagen-Induced Arthritis in Mice

Chrysanthemum zawadskii var. latilobum (CZ) has been used for beverage or tea and also as folk medicine for the remedy of diverse inflammatory diseases. Nevertheless, the therapeutic effect of CZ on arthritis remains to be unknown. In this paper we aim to investigate the CZ's antiarthritic effect and mechanism of action both in vitro and in vivo. To assess CZ's antiarthritic effect, mouse models of type II collagen-induced arthritis (CIA) were used. Mice were used to gauge clinical arthritis index and histopathological changes. Reverse transcriptase-polymerase chain reaction (RT-PCR), western blotting, electrophoretic mobility shift assay (EMSA), and other biological methods were adopted to measure CZ's effect on arthritis and to understand the veiled mechanism of action. CZ greatly suppressed CIA, histopathological score, bone erosion, and osteoclast differentiation. Mechanistically, CZ inhibited the production of various inflammatory and arthritic mediators like inflammatory cytokines, matrix metalloproteinases (MMPs), and chemokines. Of note, CZ significantly suppressed the activation of the NF-κB pathway in vivo. CZ exerted an antiarthritic effect in CIA mice by curbing the production of crucial inflammatory and arthritis mediators. This study warrants further investigation of CZ for the use in human rheumatoid arthritis (RA).

An update on dietary phenolic compounds in the prevention and management of rheumatoid arthritis

Certain nutritional components influence the cellular metabolism and interfere in the pathological inflammatory process, so that they may act as a coadjuvant in the treatment of many chronic inflammatory diseases, including rheumatoid arthritis (RA).

Role of Chlorogenic Acids in Controlling Oxidative and Inflammatory Stress Conditions

Chlorogenic acids (CGAs) are esters formed between caffeic and quinic acids, and represent an abundant group of plant polyphenols present in the human diet. CGAs have different subgroups that include caffeoylquinic, p-coumaroylquinic, and feruloyquinic acids. Results of epidemiological studies suggest that the consumption of beverages such as coffee, tea, wine, different herbal infusions, and also some fruit juices are linked to reduced risks of developing different chronic diseases. These beverages contain CGAs present in different concentrations and isomeric mixtures. The underlying mechanism(s) for specific health benefits attributed to CGAs involves mitigating oxidative stress, and hence the related adverse effects associated with an unbalanced intracellular redox state. There is also evidence to show that CGAs exhibit anti-inflammatory activities by modulating a number of important metabolic pathways. This review will focus on three specific aspects of the relevance of CGAs in coffee beverages; namely: (1) the relative composition of different CGA isomers present in coffee beverages; (2) analysis of in vitro and in vivo evidence that CGAs and individual isomers can mitigate oxidative and inflammatory stresses; and (3) description of the molecular mechanisms that have a key role in the cell signaling activity that underlines important functions.

The therapeutic effect of chlorogenic acid against Staphylococcus aureus infection through sortase A inhibition

The emergence and wide spread of multi-drug resistant Staphylococcus aureus (S. aureus) requires the development of new therapeutic agents with alternative modes of action. Anti-virulence strategies are hoped to meet that need. Sortase A (SrtA) has attracted great interest as a potential drug target to treat infections caused by S. aureus, as many of the surface proteins displayed by SrtA function as virulence factors by mediating bacterial adhesion to specific organ tissues, invasion of host cells, and evasion of the host-immune responses. It has been suggested that inhibitors of SrtA might be promising candidates for the treatment and/or prevention of S. aureus infections. In this study, we report that chlorogenic acid (CHA), a natural compound that lacks significant anti-S. aureus activity, inhibit the activity of SrtA in vitro (IC50 = 33.86 ± 5.55 μg/ml) and the binding of S. aureus to fibrinogen (Fg). Using molecular dynamics simulations and mutagenesis assays, we further demonstrate that CHA binds to the binding sites of C184 and G192 in the SrtA. In vivo studies demonstrated that CHA prevent mice from S. aureus-induced renal abscess, resulting in a significant survival advantage. These findings indicate that CHA is a promising therapeutic compound against SrtA during S. aureus infections.

Rhodiola rosea suppresses thymus T-lymphocyte apoptosis by downregulating tumor necrosis factor-α-induced protein 8-like-2 in septic rats

In recent years, several studies have shown that Rhodiola rosea can enhance cellular immunity and humoral immune function in mice, and thus, it has become a research hotspot. However, its underlying mechanism of action has remained elusive. The present study investigated whether Rhodiola rosea was able to downregulate the expression of tumor necrosis factor-α-inducible protein 8-like 2 (TIPE2), thereby inhibiting the expression of apoptotic genes, attenuating T-lymphocyte apoptosis and improving immunity in septic mice. A mouse model of caecal ligation and puncture (CLP)-induced sepsis was established, and animals in the treatment group were pre-treated with an intraperitoneal injection of Rhodiola rosea extract, while animals in the control group and sham-operated group were injected with an equivalent amount of normal saline. TIPE2, B-cell lymphoma 2 (Bcl-2), Fas and Fas ligand (FasL) mRNA and protein levels in thymic T cells were determined using reverse transcription quantitative polymerase chain reaction and western blot analysis, respectively. Furthermore, the thymus T-lymphocyte apoptosis rate, thymus T-lymphocyte count and thymus T-lymphocyte sub-sets were assessed using flow cytometry. Levels of T-helper cell type 1 (Th1) cytokines [Interleukin (IL)-2, IL-12 and interferon (IFN)-γ] and Th2 cytokines (IL-4 and IL-10) were determined using ELISA. The results showed that, compared to that in the CLP group, the expression of TIPE2, Fas and FasL in the treatment group was significantly decreased, while the expression of Bcl-2 was increased (P<0.05). The thymus lymphocyte count in the CLP group was significantly higher compared with that in the treatment group (P<0.05). Furthermore, the apoptotic rate of thymus T-lymphocytes in the treatment group was significantly lower than that in the CLP group (P<0.05). In addition, treatment with Rhodiola rosea rescued decreased in the counts of the CD3⁺ T and CD4⁺ T sub-sets of thymus T lymphocytes in the CLP group (P<0.05), while not affecting the increased levels of Th2 cytokines (IL-4 and IL-10) in the CLP group compared with those in the control groups. In addition, the Th1 cytokines (IL-12, IL-2 and IFN-γ) were significantly increased (P<0.05) in the CLP group, and treatment with Rhodiola rosea led to further increases. The thymus index of septic mice treated with Rhodiola rosea as well as their survival rate were improved as compared with those in the CLP group. These findings suggested that Rhodiola rosea has protective effects against sepsis by decreasing apoptosis, increasing Th1 cytokines and enhancing the host’s immunity via the regulation of TIPE2 expression.

IRAK4 as a Molecular Target in the Amelioration of Innate Immunity–Related Endotoxic Shock and Acute Liver Injury by Chlorogenic Acid

Mice lacking the IL-1R–associated kinase 4 (IRAK4) are completely resistant to LPS-induced endotoxic disorder or the TLR9 agonist CpG DNA plus d-galactosamine–induced acute liver injury (ALI), whereas wild-type strains succumb. However, translational drugs against sepsis or ALI remain elusive. Lonicerae flos extract is undergoing the clinical trial phase I in LPS-injected healthy human volunteers for sepsis treatment. In the current study, chlorogenic acid (CGA), a major anti-inflammatory constituent of lonicerae flos extract, rescued endotoxic mortality of LPS-intoxicated C57BL/6 mice, as well as ameliorated ALI of LPS/d-galactosamine–challenged C57BL/6 mice. As a mechanism, CGA inhibited various TLR agonist–, IL-1α–, or high-mobility group box-1–stimulated autophosphorylation (activation) of IRAK4 in peritoneal macrophages from C57BL/6 or C3H/HeJ mice via directly affecting the kinase activity of IRAK4, a proximal signal transducer in the MyD88-mediated innate immunity that enhances transcriptional activity of NF-κB or AP-1. CGA consequently attenuated protein or mRNA levels of NF-κB/AP-1 target genes encoding TNF-α, IL-1α, IL-6, and high-mobility group box-1 in vivo under endotoxemia or ALI. Finally, this study suggests IRAK4 as a molecular target of CGA in the treatment of innate immunity–related shock and organ dysfunction following insult of various TLR pathogens from bacteria and viruses.

Chlorogenic acid alters the voltage-gated potassium channel currents of trigeminal ganglion neurons

Chlorogenic acid (5-caffeoylquinic acid, CGA) is a phenolic compound that is found ubiquitously in plants, fruits and vegetables and is formed via the esterification of caffeic acid and quinic acid. In addition to its notable biological functions against cardiovascular diseases, type-2 diabetes and inflammatory conditions, CGA was recently hypothesized to be an alternative for the treatment of neurological diseases such as Alzheimer's disease and neuropathic pain disorders. However, its mechanism of action is unclear. Voltage-gated potassium channel (Kv) is a crucial factor in the electro-physiological processes of sensory neurons. Kv has also been identified as a potential therapeutic target for inflammation and neuropathic pain disorders. In this study, we analysed the effects of CGA on the two main subtypes of Kv in trigeminal ganglion neurons, namely, the I_K,A and I_K,V channels. Trigeminal ganglion (TRG) neurons were acutely disassociated from the rat TRG, and two different doses of CGA (0.2 and 1 mmol⋅L⁻¹) were applied to the cells. Whole-cell patch-clamp recordings were performed to observe alterations in the activation and inactivation properties of the I_K,A and I_K,V channels. The results demonstrated that 0.2 mmol⋅L⁻¹ CGA decreased the peak current density of I_K,A. Both 0.2 mmol⋅L⁻¹ and 1 mmol⋅L⁻¹ CGA also caused a significant reduction in the activation and inactivation thresholds of I_K,A and I_K,V. CGA exhibited a strong effect on the activation and inactivation velocities of I_K,A and I_K,V. These findings provide novel evidence explaining the biological effects of CGA, especially regarding its neurological effects.

Inhibition of acid-sensing ion channels by chlorogenic acid in rat dorsal root ganglion neurons

Chlorogenic acid (CGA) is one of the most abundant polyphenol compounds in the human diet. Recently, it is demonstrated to have potent antinociceptive effect. However, little is understood about the mechanism underlying CGA analgesia. Here, we have found that CGA can exert an inhibitory effect on the functional activity of native acid-sensing ion channels (ASICs) in rat dorsal root ganglion (DRG) neurons. First, CGA decreased the peak amplitude of proton-gated currents mediated by ASICs in a concentration-dependent manner. Second, CGA shifted the proton concentration-response curve downward, with a decrease of 41.76 ± 8.65% in the maximum current response to protons but with no significant change in the pH0.5 value. Third, CGA altered acidosis-evoked membrane excitability of rat DRG neurons and caused a significant decrease in the amplitude of the depolarization and the number of action potentials induced by acid stimuli. Finally, peripheral administered CGA attenuated nociceptive response to intraplantar injection of acetic acid in rats. ASICs are distributed in peripheral sensory neurons and participate in nociception. Our findings CGA inhibition of native ASICs indicated that CGA may exert analgesic action by modulating ASICs in the primary afferent neurons, which revealed a novel cellular and molecular mechanism underlying CGA analgesia.

Inhibition of IRAK-4 activity for rescuing endotoxin LPS-induced septic mortality in mice by lonicerae flos extract

Lonicerae flos extract (HS-23) is a clinical candidate currently undergoing Phase I trial in lipopolysaccharide (LPS)-injected healthy human volunteers, but its molecular basis remains to be defined. Here, we investigated protective effects of HS-23 or its major constituents on Escherichia coli LPS-induced septic mortality in mice. Intravenous treatment with HS-23 rescued LPS-intoxicated C57BL/6J mice under septic conditions, and decreased the levels of cytokines such as tumor necrosis factor α (TNF-α), interleukin (IL)-1β and high-mobility group box-1 (HMGB-1) in the blood. Chlorogenic acid (CGA) and its isomers were assigned as major constituents of HS-23 in the protection against endotoxemia. As a molecular mechanism, HS-23 or CGA isomers inhibited endotoxin LPS-induced autophosphorylation of the IL-1 receptor-associated kinase 4 (IRAK-4) in mouse peritoneal macrophages as well as the kinase activity of IRAK-4 in cell-free reactions. HS-23 consequently suppressed downstream pathways critical for LPS-induced activation of nuclear factor (NF)-κB or activating protein 1 (AP-1) in the peritoneal macrophages. HS-23 also inhibited various toll-like receptor agonists-induced nitric oxide (NO) production, and down-regulated LPS-induced expression of NF-κB/AP-1-target inflammatory genes in the cells. Taken together, HS-23 or CGA isomers exhibited anti-inflammatory therapy against LPS-induced septic mortality in mice, at least in part, mediated through the inhibition of IRAK-4.

Chlorogenic acid administered intrathecally alleviates mechanical and cold hyperalgesia in a rat neuropathic pain model

Chlorogenic acid (CGA), one of the most abundant dietary polyphenols, is known to have various physiological properties. Although CGA is reported to have an antinociceptive effect on acute and inflammatory pain, little is known about its effect on neuropathic pain or its action site. The aim of the present study was to determine whether intrathecally administered CGA can ameliorate hyperalgesia in a neuropathic pain model. Chronic constriction injury to the sciatic nerve was induced in male Sprague-Dawley rats. CGA (0.5, 1, or 2mg) was administered intrathecally to examine the effects on mechanical, thermal, and cold hyperalgesia using the electronic von Frey test, plantar test, and cold plate test, respectively. A rotarod test was also performed to assess motor function. To identify the neurotransmitter pathway involved in the spinal action of CGA, the present study examined the effect of intrathecal pretreatment with several antagonists of spinal pain processing receptors on the action of CGA in the electronic von Frey test and cold plate test. Spinally applied CGA dose-dependently alleviated mechanical and cold hyperalgesia. Conversely, CGA had no effect on thermal hyperalgesia. At the highest dose, CGA affected motor performance. The antihyperalgesic action of CGA was partially reversed by bicuculline, an γ-aminobutyric acidA (GABAA) receptor antagonist, at a dose that did not affect baseline behavioral responses. These findings suggest that CGA ameliorates mechanical and cold hyperalgesia partly by activating GABAergic transmission in the spinal cord, and that CGA may be useful for novel treatments for neuropathic pain.

Antihyperalgesic activity of chlorogenic acid in experimental neuropathic pain

Chlorogenic acid (CGA) is a natural organic phenolic compound that is found in many plants, fruits and vegetables. CGA has beneficial bioactivities and strong therapeutic effects in inflammatory processes. CGA-rich fractions have analgesic activity but CGA has not been tested previously in neuropathic pain, which results from tissue damage, inflammation or injury of the nervous system. Chronic constrictive nerve injury (CCI) is a peripheral neuropathic pain model which initiates an inflammatory cascade. We aimed to determine possible antihyperalgesic effects of CGA in neuropathic pain. Our study showed for the first time that CGA [50, 100 and 200 mg/kg; intraperitoneally (i.p.)] produced significant dose- and time-dependent antihyperalgesic activity in CCI-induced neuropathic pain. In addition, chronic administration of CGA (100 mg/kg/day; i.p. for 14 days) prevented the development of mechanical hyperalgesia and attenuated CCI-induced histopathological changes. On the other hand, CGA (200 mg/kg) did not affect falling latencies of rats in the rota rod test. Hence, CGA might represent a novel potential therapeutic option for the management of neuropathic pain.