Pomegranate supplementation attenuates inflammation, joint dysfunction via inhibition of NF-κB signaling pathway in experimental models of rheumatoid arthritis

The power of Punica granatum: A natural remedy for oxidative stress and inflammation; a narrative review

ETHNOPHARMACOLOGICAL RELEVANCE

Pomegranate 'Punica granatum' offers multiple health benefits, including managing hypertension, dyslipidemia, hyperglycemia, insulin resistance, and enhancing wound healing and infection resistance, thanks to its potent antioxidant and anti-inflammatory properties. It has been symbolized by life, health, femininity, fecundity, and spirituality.

AIM OF THE STUDY

Although laboratory and animal studies have been conducted on the healing effects of pomegranate, there needs to be a comprehensive review on its anti-oxidative and anti-inflammatory effects in chronic disorders. We aim to provide a comprehensive review of these effects based on in-vitro, in-vivo, and clinical studies conducted in managing various disorders.

MATERIALS AND METHODS

A comprehensive search of in-vitro, in-vivo, and clinical findings of pomegranate and its derivatives focusing on the highly qualified original studies and systematic reviews are carried out in valid international web databases, including Web of Science, PubMed, Scopus, and Cochrane Library.

RESULTS

Relevant studies have demonstrated that pomegranate and its derivatives can modulate the expression and activity of several genes, enzymes, and receptors through influencing oxidative stress and inflammation pathways. Different parts of pomegranate; roots, bark, blossoms, fruits, and leaves contain various bioactive compounds, such as polyphenols, flavonoids, anthocyanins, and ellagitannins, that have preventive and therapeutic effects against many disorders such as cardiovascular diseases, diabetes, neurological diseases, and cancers without any serious adverse effects.

CONCLUSIONS

Most recent scientific evidence indicates that all parts of the pomegranate can be helpful in treating a wide range of chronic disorders due to its anti-oxidative and anti-inflammatory activities. Since the safety of pomegranate fruit, juice, and extracts is established, further investigations can be designed by targeting its active antioxidant and anti-inflammatory constituents to discover new drugs.

Deciphering the therapeutic potential of trimetazidine in rheumatoid arthritis via targeting mi-RNA128a, TLR4 signaling pathway, and adenosine-induced FADD-microvesicular shedding: In vivo and in silico study

Rheumatoid arthritis (RA) is a debilitating autoimmune condition characterized by chronic synovitis, joint damage, and inflammation, leading to impaired joint functionality. Existing RA treatments, although effective to some extent, are not without side effects, prompting a search for more potent therapies. Recent research has revealed the critical role of FAS-associated death domain protein (FADD) microvesicular shedding in RA pathogenesis, expanding its scope beyond apoptosis to include inflammatory and immune pathways. This study aimed to investigate the intricate relationship between mi-RNA 128a, autoimmune and inflammatory pathways, and adenosine levels in modulating FADD expression and microvesicular shedding in a Freund's complete adjuvant (FCA) induced RA rat model and further explore the antirheumatoid potency of trimetazidine (TMZ). The FCA treated model exhibited significantly elevated levels of serum fibrogenic, inflammatory, immunological and rheumatological diagnostic markers, confirming successful RA induction. Our results revealed that the FCA-induced RA model showed a significant reduction in the expression of FADD in paw tissue and increased microvesicular FADD shedding in synovial fluid, which was attributed to the significant increase in the expression of the epigenetic miRNA 128a gene in addition to the downregulation of adenosine levels. These findings were further supported by the significant activation of the TLR4/MYD88 pathway and its downstream inflammatory IkB/NFB markers. Interestingly, TMZ administration significantly improved, with a potency similar to methotrexate (MTX), the deterioration effect of FCA treatment, as evidenced by a significant attenuation of fibrogenic, inflammatory, immunological, and rheumatological markers. Our investigations indicated that TMZ uniquely acted by targeting epigenetic miRNA128a expression and elevating adenosine levels in paw tissue, leading to increased expression of FADD of paw tissue and mitigated FADD microvesicular shedding in synovial fluid. Furthermore, the group treated with TMZ showed significant downregulation of TLR4/MYD88 and their downstream TRAF6, IRAK and NF-kB. Together, our study unveils the significant potential of TMZ as an antirheumatoid candidate, offering anti-inflammatory effects through various mechanisms, including modulation of the FADD-epigenetic regulator mi-RNA 128a, adenosine levels, and the TLR4 signaling pathway in joint tissue, but also attenuation of FADD microvesicular shedding in synovial fluid. These findings further highlight the synergistic administration of TMZ and MTX as a potential approach to reduce adverse effects of MTX while improving therapeutic efficacy.

Novel trifluoromethyl ketone derivatives as oral cPLA2/COX-2 dual inhibitors for resolution of inflammation in rheumatoid arthritis

Thirty-five trifluoromethyl hydrazones and seventeen trifluoromethyl oxime esters were designed and synthesized via molecular hybridization. All the target compounds were initially screened for in vitro anti-inflammatory activity by assessing their inhibitory effect on NO release in LPS-stimulated RAW264.7 cells, and the optimal compound was finally identified as 2-(3-Methoxyphenyl)-N'-((6Z,9Z,12Z,15Z)-1,1,1-trifluorohenicosa-6,9,12,15-tetraen-2-ylidene)acetohydrazide (F26, IC50 = 4.55 ± 0.92 μM) with no cytotoxicity. Moreover, F26 potently reduced the production of PGE2 in LPS-stimulated RAW264.7 cells compared to indomethacin. The interaction of F26 with COX-2 and cPLA2 was directly verified by the CETSA technique. F26 was found to modulate the phosphorylation levels of p38 MAPK and NF-κB p65, as well as the protein expression of IκB, cPLA2, COX-2, and iNOS in LPS-stimulated rat peritoneal macrophages. Additionally, F26 was observed to prevent the nuclear translocation of NF-κB p65 in LPS-stimulated rat peritoneal macrophages by immunofluorescence localization. Therefore, the aforementioned in vitro experiments demonstrated that F26 blocked the p38 MAPK and NF-κB pathways by binding to COX-2 and cPLA2. In the adjuvant-induced arthritis model, F26 demonstrated a significant effect in preventing arthritis symptoms and inflammatory status in rats, exerting an immunomodulatory role by regulating the homeostasis between Th17 and Treg through inhibition of the p38 MAPK/cPLA2/COX-2/PGE2 and NF-κB pathways. Encouragingly, F26 caused less acute ulcerogenicity in rats at a dose of 50 mg/kg compared to indomethacin. Overall, F26 is a promising candidate worthy of further investigation for treating inflammation and associated pain with lesser gastrointestinal irritation, as well as other symptoms in which cPLA2 and COX-2 are implicated in the pathophysiology.

Pomegranate attenuates kidney injury in cyclosporine-induced nephrotoxicity in rats by suppressing oxidative stress

To investigate the effect of pomegranate juice (PJ) on the cyclosporine (CsA)-induced nephrotoxicity in rats, 80 rats were divided into four groups. The first group was regarded a negative control group, and the others were as follows: group 2 (CsA group) received CsA in a dose of 25 mg/kg/day orally, group 3 (treated group) received CsA in a dose of 25 mg/kg/day plus 2.5 mL/day of PJ, and group 4 (PJ group) received 2.5 mL of PJ daily. By the end of the 21st day, plasma creatinine, blood urea nitrogen (BUN), creatinine clearance, urinary KIM-1, and NGAL were determined. Histopathological investigation and the determination of malondialdehyde and antioxidant enzymes were analyzed in kidney tissues. The results show that plasma creatinine, BUN, creatinine clearance, and kidney injury molecule-1 and neutrophil gelatinase-associated lipocalin were significantly altered in the CsA group. The supplement of PJ attenuated the alteration in these parameters. The treatment with PJ also prohibits the CsA-induced alteration in the histopathology, lipid peroxidation, and antioxidant enzymes. We can conclude that PJ protects against CsA-induced nephrotoxicity due to its antioxidant effects.

Efficacy and safety of dietary polyphenols in rheumatoid arthritis: A systematic review and meta-analysis of 47 randomized controlled trials

OBJECTIVE

To evaluate safety and efficacy of dietary polyphenols in the treatment of rheumatoid arthritis (RA).

METHODS

CNKI, Pubmed, Cochrane library, Embase were searched to collect randomized controlled trials (RCTs) of dietary polyphenols in the treatment of RA. The databases were searched from the time of their establishment to November 8nd, 2022. After 2 reviewers independently screened the literature, extracted data, and assessed the risk of bias of the included studies, Meta-analysis was performed using RevMan5.4 software.

RESULTS

A total of 49 records (47 RCTs) were finally included, involving 3852 participants and 15 types of dietary polyphenols (Cinnamon extract, Cranberry extract, Crocus sativus L. extract, Curcumin, Garlic extract, Ginger extract, Hesperidin, Olive oil, Pomegranate extract, Puerarin, Quercetin, Resveratrol, Sesamin, Tea polyphenols, Total glucosides of paeony). Pomegranate extract, Resveratrol, Garlic extract, Puerarin, Hesperidin, Ginger extract, Cinnamon extract, Sesamin only involve in 1 RCT. Cranberry extract, Crocus sativus L. extract, Olive oil, Quercetin, Tea polyphenols involve in 2 RCTs. Total glucosides of paeony and Curcumin involve in more than 3 RCTs. These RCTs showed that these dietary polyphenols could improve disease activity score for 28 joints (DAS28), inflammation levels or oxidative stress levels in RA. The addition of dietary polyphenols did not increase adverse events.

CONCLUSION

Dietary polyphenols may improve DAS28, reduce C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR), and improve oxidative stress, etc. However, more RCTs are needed to verify or modify the efficacy and safety of dietary polyphenols.

SYSTEMATIC REVIEW REGISTRATION

https://www.crd.york.ac.uk/prospero/, identifier CRD42022315645.

Potential profound fluctuation in tacrolimus concentration on consumption of pomegranate rind extract: A Pharmacokinetic Experiment

Background: Presently, varied case reports demonstrated an increase or decrease in blood concentration of diverse conventional drugs, often co-administered with edible fruits, spices, or vegetables. The overarching aim of this research is to elucidate the fluctuations in tacrolimus (TAC) blood concentration on the consumption of pomegranate rind extract (PRE). Methods: A pharmacokinetic (PK) study was conducted with two groups, vis-a-vis PRE + TAC (3 mg/kg) and TAC (3 mg/kg) alone groups. An experimental study was conducted in three different manners: Single-dose (S) PRE (200 mg/kg), 7-day repetitive (7-R) PRE (200 mg/kg) dosing, and multiple (M) PRE doses (100, 200, 400, and 800 mg/kg). All the blood samples (approximately 300 μl) were drawn at different time intervals, i.e., 30 min, 1, 2, 4, 8, and 12 h after oral administration of TAC (3 mg/kg). The estimation of TAC in rat plasma was done using the hyphenated technique LC-MS/MS where the mass spectrometer used was a triple-stage quadrupole in multiple-reaction monitoring (MRM) mode. Results: The findings depict that in comparison with the TAC (3 mg/kg) alone group with the 7-day repetitive (7-R) PRE (200 mg/kg) dosing, the Cmax was found to be 9.03 ± 1.21 ng/ml; AUC from time zero to infinity (AUC0-∞), 61.91 ± 17.37 ngh/ml, while the TAC (3 mg/kg) + PRE group exhibited an increase in PK parameters of TAC (Cmax 22.48 ± 3.07 ng/ml; AUC0-∞ 153.08 ± 13.24 ng h/ml). The authors further investigated in what manner the PRE affects the PK of TAC in animals. For this, docking studies with major phytoconstituents present in the PRE with CYP3A4 isoenzyme were carried out. Ellagitannins (dock score, -11.64) and punicalagin (dock score, -10.68) were again used for molecular simulation studies with TAC. To validate our findings, a CYP3A4 inhibitory in vitro assay was conducted. Conclusion: Based on the integrated in vivo and in silico studies, we concluded that pomegranate rind extract interacts strongly with CYP isoenzyme and is therefore responsible for the altered PK profile of TAC.

Hydrolyzable Tannins in the Management of Th1, Th2 and Th17 Inflammatory-Related Diseases

Plants rich in hydrolyzable tannins were traditionally used all over the world for a variety of chronic inflammatory disorders, including arthritis, colitis, and dermatitis. However, the knowledge of their immunological targets is still limited though fundamental for their rational use in phytotherapy. The recent advances regarding the pathogenesis of inflammatory-based diseases represent an opportunity to elucidate the pharmacological mechanism of plant-derived metabolites with immunomodulatory activity. This review collects recent articles regarding the role of hydrolyzable tannins and their gut metabolites in Th1, Th2, and Th17 inflammatory responses. In line with the traditional use, rheumatoid arthritis (RA), inflammatory bowel diseases (IBDs), psoriasis, atopic dermatitis (AD), and asthma were the most investigated diseases. A substantial body of in vivo studies suggests that, beside innate response, hydrolyzable tannins may reduce the levels of Th-derived cytokines, including IFN-γ, IL-17, and IL-4, following oral administration. The mode of action is multitarget and may involve the impairment of inflammatory transcription factors (NF-κB, NFAT, STAT), enzymes (MAPKs, COX-2, iNOS), and ion channels. However, their potential impact on pathways with renewed interest for inflammation, such as JAK/STAT, or the modulation of the gut microbiota demands dedicate studies.

Traditional Tibetan medicine: therapeutic potential in rheumatoid arthritis

Rheumatoid arthritis (RA) is a severe inflammatory autoimmune disease characterized by the failed spontaneous resolution of inflammation. The induction of immune regulation and resolution of inflammatory pathways are effective in alleviating inflammation in RA. As the oldest medical system in the world, traditional Tibetan medicine (TTM) has a long history of preventing and treating RA. This review provides a comprehensive overview of medicinal plants with anti-RA activity in the TTM system, using classic books of Tibetan medicine, modern research literature, and drug standards. A total of 27 species have been found to be effective in treating RA, including Tinospora sinensis (Lour.) Merr., Terminalia chehula Retz., P. hookeri (C. B. Clarke) Hock.), and Aconitum pendulum Busch. Alkaloids, flavonoids, polyphenols, and terpenoids have turned out to be the major bioactive components for RA treatment. The inhibition of pro-inflammatory cytokine expression by mediating the NF-κB, MAPK, and JAK/STAT pathways is the core mechanism in RA treatment. In conclusion, this review provides key information and research perspectives for further research on the anti-RA effects of TTM.

Macrophage-Targeted Punicalagin Nanoengineering to Alleviate Methotrexate-Induced Neutropenia: A Molecular Docking, DFT, and MD Simulation Analysis

Punicalagin is the most bioactive pomegranate polyphenol with high antioxidant and free-radical scavenging activity and can potentially cure different ailments related to the cardiovascular system. The current research work was envisioned to predict the targeting efficiency of punicalagin (PG) nanoparticles to the macrophages, more specifically to bone marrow macrophages. For this, we selected mannose-decorated PLGA-punicalagin nanoparticles (Mn-PLGA-PG), and before formulating this nanocarrier in laboratory settings, we predicted the targeting efficiency of this nanocarrier by in silico analysis. The analysis proceeded with macrophage mannose receptors to be acquainted with the binding affinity and punicalagin-based nanocarrier interactions with this receptor. In silico docking studies of macrophage mannose receptors and punicalagin showed binding interactions on its surface. PG interacted with hydrogen bonds to the charged residue ASP668 and GLY666 and polar residue GLN760 of the Mn receptor. Mannose with a docking score of −5.811 Kcal/mol interacted with four hydrogen bonds and the mannose receptor of macrophage, and in PLGA, it showed a −4.334 Kcal/mol docking score. Further, the analysis proceeded with density functional theory analysis (DFT) and HOMO–LUMO analysis, followed by an extensive 100 ns molecular dynamics simulation to analyse the trajectories showing the slightest deviation and fluctuation. While analysing the ligand and protein interaction, a wonderful interaction was found among the atoms of the ligand and protein residues. This computational study confirms that this nanocarrier could be a promising lead molecule to regulate the incidence of drug-induced neutropenia. Furthermore, experimental validation is required before this can be stated with complete confidence or before human use.

Antinociceptive Synergism of Pomegranate Peel Extract and Acetylsalicylic Acid in an Animal Pain Model

Several modern drugs, which are derived from traditional herbal medicine are used in contemporary pharmacotherapy. Currently, the study of drug–plant interactions in pain has increased in recent years, looking for greater efficacy of the drug and reduce side effects. The antinociception induced by intragastric co-administration of the combination of pomegranate peel extract (PoPEx) and acetylsalicylic acid (ASA) was assessed using the isobolographic analysis in formalin test (nociceptive and inflammatory pain). The effective dose that produced 30% of antinociception (ED₃₀) was calculated for both drugs from the logarithmic dose–response curves, subsequently generating a curve with the combination on fixed proportions (1:1) of PoPEx and ASA. Through isobolographic analysis, this experimental ED₃₀ was compared with the calculated theoretical additive ED₃₀. The result was a synergistic interaction, the experimental ED₃₀ was significantly smaller (p < 0.05) than the theoretical ED₃₀. The antinociceptive mechanism of the PoPEx-ASA combination involves the l-Arginine/NO/cGMP pathway, antioxidant capacity, and high content of total phenols. These findings suggest that an interaction between PoPEx and ASA could be a novel treatment for inflammatory and nociceptive pain, also diminish the secondary reactions of ASA.

Tropical Fruits and Their Co-Products as Bioactive Compounds and Their Health Effects: A Review

Tropical and subtropical fruits are recognized as a source of a high content of bioactive compounds and health promoting properties due to their nutritional composition. These beneficial health effects are related to the content of several of these bioactive compounds, mainly flavonoids and non-flavonoid phenolics. Many of these compounds are common in different tropical fruits, such as epicatechin in mango, pineapple, and banana, or catechin in pineapple, cocoa or avocado. Many studies of tropical fruits had been carried out, but in this work an examination is made in the current literature of the flavonoids and non-flavonoid phenolics content of some tropical fruits and their coproducts, comparing the content in the same units, as well as examining the role that these compounds play in health benefits.

Potential effects of pomegranate (Punica granatum) on rheumatoid arthritis: A systematic review

BACKGROUND

Taking into account the adverse impact of the drug therapy on rheumatoid arthritis (RA), adjuvant therapies without such undesirable effects have recently gained increasing interest. Several studies have examined the potential properties of pomegranate on RA with some uncertain mechanisms suggested. This review aimed to systematically review the available evidence in this regard.

METHODS

Electronic databases including PubMed, WOS, Cochrane Library, Scopus, Embase and a search engine Google Scholar were searched until March 2020 and search alert services have been applied to identify related articles published after the initial search. There was no limitation regarding language or publication date. Relevant clinical, animal and in vitro studies were chosen. Review papers, conference abstracts, book chapters and articles regarding the effects of pomegranate in combination with other plants as well as articles regarding the effects of pomegranate on other illnesses were deleted.

RESULTS

Twelve papers were considered in current systematic review. Human, animal and in vitro studies indicated the beneficial effects of pomegranate on clinical symptoms, inflammatory and oxidative factors in RA. Pomegranate is capable to manage RA complications by reducing the inflammation and oxidative stress. No critical unfavourable results following pomegranate consumption were reported.

CONCLUSION

This paper gives compelling evidence regarding the efficacy of pomegranate in RA and justifies the significance of further clinical researches.

Euphorbia prostata Exerts Potent Anti-Inflammatory and Anti-Arthritic Activity in Downregulating the Increased Expression of Pro-Inflammatory Cytokines

Background: Euphorbia prostrata constitutes a herbal medication widely used to cure numerous inflammatory diseases occurring either alone or in conjunction with other herbal formulations. The research conducted was devised with the aim of determining the effect of Euphorbia prostrata hydroalcoholic leaf extract on paw swelling, joint destruction, and the formation of inflammation-producing cytokines in animal models of rheumatoid arthritis. Methods: Hydroalcoholic Euphorbia prostrata extract and a reference drug (indomethacin 3mg/kg), were both administered orally on a daily basis at varying doses; low (50 mg/kg), medium (100 mg/kg), and high (200 mg/kg) for a period of 21 days. Other parameters affecting the functional components of bone include joint diameter measurements and histopathological investigations. Immunohistochemical analysis of Interleukin (IL-1, IL-6) and Nuclear Factor(NF-κB)in ankle joint tissue was performed. Results: The research findings indicated that a significant (p<0.05) dose-dependent reduction in inflammation results from the administering of Euphorbia prostrata at varying doses. A 200mg/kg dose of Euphorbia prostrata with a significance of p<0.001 produced a marked reduction in both inflammation and joint dysfunction. It was concluded, therefore, that such a dose attenuates paw oedema and inflammation, while also reversing bone damage through the inhibition of activated pro-inflammatory mediators and, specifically, NF-κB-mediated production of cytokines. Conclusion: The research presented here concludes that Euphorbia prostrata hydroalcoholic extract can be potentially employed in the treatment and management of rheumatoid arthritis since it reduces symptoms of inflammation, inhibits macrophage activity and modulates IL-1, IL-6 and NF-κB.

Characterization of pomegranate peel extracts obtained using different solvents and their effects on cell cycle and apoptosis in leukemia cells

Pomegranate (Punica granatum L.) has been used in traditional herbal medicine by several cultures as an anti-inflammatory, antioxidant, antihyperglycemic, and for treatment and prevention of cancer and other diseases. Different parts of the fruit, extraction methods, and solvents can define the chemical profile of the obtained extracts and their biological activities. This study aimed to characterize the chemical profile of peel extracts collected using different extraction solvents and their biological effects on the cell cycle and apoptosis of THP-1 leukemic cells. Aqueous extract presented the highest content of punicalagins (α pun = 562.26 ± 47.14 mg/L and β pun = 1,251.13 ± 22.21 mg/L) and the lowest content of ellagic acid (66.38 ± 0.21 mg/L), and it promoted a significant impairment of the cell cycle S phase. In fact, punicalagin-enriched fraction, but not an ellagic acid-enriched fraction, caused an S phase cell cycle arrest. All extracts increased the number of apoptotic cells. Punicalagin-enriched fraction increased the percentage of cells with fragmented DNA, which was intensified by ellagic acid combination. The treatment combining punicalagin and ellagic acid fractions increased the apoptotic cleaved PARP1 protein and reduced the activation of the growth-related mTOR pathway. Thus, these results evidence that solvent choice is critical for the phenolic compounds profile of pomegranate peel extracts and their biological activities.

Pomegranate as a Potential Alternative of Pain Management: A Review

The use of complementary medicine has recently increased in an attempt to find effective alternative therapies that reduce the adverse effects of drugs. Punica granatum L. (pomegranate) has been used in traditional medicine for different kinds of pain. This review aims to explore the scientific evidence about the antinociceptive effect of pomegranate. A selection of original scientific articles that accomplished the inclusion criteria was carried out. It was found that different parts of pomegranate showed an antinociceptive effect; this effect can be due mainly by the presence of polyphenols, flavonoids, or fatty acids. It is suggested in the literature that the mechanisms of action may be related to the activation of the L-arginine / NO pathway, members of the TRP superfamily (TRPA1 or TRPV1) and the opioid system. The implications for the field are to know the mechanisms of action by which this effect is generated and thus be able to create alternative treatments for specific types of pain, which help alleviate it and reduce the adverse effects produced by drugs. The results propose that pomegranate and secondary metabolites could be considered in the treatment of inflammatory, nociceptive, and neuropathic pain.

Wogonin ameliorate complete Freund's adjuvant induced rheumatoid arthritis via targeting NF-κB/MAPK signaling pathway

Rheumatoid arthritis (RA) is a chronic and accelerated autoimmune illness with proliferative and damaging synovitis, resulting in joint death and cartilage and bone erosion. This study focused on the potential therapeutic effect of wogonin on complete Freund's adjuvant (CFA) induced RA in rats and the underlying mechanisms. Arthritis was experimentally caused in rats by subcutaneously injecting 0.1 mL of CFA into the subplantar area of the left hind paw under moderate anesthesia on day zero. The regular oral doses of indomethacin/wogonin began on day zero and proceeded after injection to day 35. Wogonin reduced arthritic score considerably, enhanced body weight, and reduced paw thickness. Wogonin also boosted red blood cell considerably along with hemoglobin and reduced white blood cell count and erythrocyte sedimentation rate. Wogonin substantially improved an altered level of oxidative stress markers, antioxidant proteins, and inflammatory cytokines in a dose-dependent way. Wogonin inhibited p38 phosphorylation triggered by CFA and p65 nuclear translocation.