The Antioxidant and Anti-Inflammatory Effects of Flavonoids from Propolis via Nrf2 and NF-κB Pathways

Study on the interventional effect and molecular mechanism of HSP72 in regulating oxidative stress by watermelon seed peptide RDPEER

Molecular docking and dynamics simulation techniques were used to analyze the binding capacity and stability of watermelon seed oligopeptides with heat shock protein 72 (HSP72), as well as the signaling pathway and mechanisms through cellular experiments. Computational simulation results indicated these peptides could form stable complexes with HSP72 through hydrogen bonds and other interactions, with the lowest free energy binding to RDPEER (-60.83 kcal/mol). In addition, by reducing HSP72 expression, RDPEER enhanced the expression of nuclear factor erythroid 2-related factor 2 (Nrf2), heme oxygenase 1 (HO-1), and superoxide dismutase (SOD). Moreover, RDPEER decreased the levels of Kelch-like ECH-associated protein 1 (Keap1) and nuclear factor kappa B subunit p65 (NF-κBp65), tumor necrosis factor-alpha (TNF-α), lipid peroxides (MDA), and reactive oxygen species (ROS), increasing cell survival rate by 20 % compared to control. Therefore, this study demonstrates that watermelon seed peptides regulate the Nrf2/NF-κB signaling axis by targeting HSP72, thereby maintaining cellular homeostasis.

Study on the Mechanism of Galangin on Hyperuricemic Nephropathy Based on Metabolomics and Network Pharmacology

Galangin (GAL), a flavonol found in Alpinia officinarum and propolis, is a promising functional food. This study investigated the therapeutic effects and mechanisms of GAL in mice with hyperuricemic nephropathy (HN) by focusing on renal metabolomics and network pharmacology. In this study, we conducted untargeted metabolomic analysis and network pharmacology prediction. Subsequently, a compound-reaction-enzyme-gene network was constructed based on the results of metabolomics and network pharmacology to elucidate potential connections. The results demonstrated that GAL can improve renal interstitial fibrosis and inflammatory infiltration and reduce serum levels of uric acid (UA), urea nitrogen (UREA), and creatinine (CREA). Metabolome analysis indicated that GAL affected thiamine, pyrimidine, nicotinate, nicotinamide, pyruvate, glyoxylate, and dicarboxylate metabolism. Network pharmacology and experimental results showed that GAL reduced the key target expression of the tumor protein P53 (TP53), tumor necrosis factor (TNF), signal transducer and activator of transcription 3 (STAT3), heat shock protein 90 alpha family class A member 1 (HSP90aa1), albumin (ALB), and caspase-3 (CASP3). GAL also downregulated the expression of Janus kinase 2 (JAK2), phospho-JAK2 (P-JAK2), and phospho-STAT3 (P-STAT3). Furthermore, a joint analysis of the metabolome and network pharmacology showed that GAL can reverse HN through amino acid metabolism, nucleotide metabolism, energy metabolism, and endocrine system pathways. GAL can alleviate HN effectively and might play synergistic therapeutic roles through regulating metabolic profiles and the JAK2/STAT3 signaling pathway.

Effect of Propolis Extracts on OxLDL and LOX-1 Levels in ApoE Knockout Mice Fed a High Fat Diet

Atherosclerosis, which has important effects on the development of cardiovascular diseases, is a widespread health problem with the highest mortality rate globally. In this study, we aimed to assess the impact of water and ethanolic extracts of propolis on oxidized low-density lipoprotein (OxLDL) and lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) in the progression of the atherosclerotic process, which is characterized by oxidative stress, inflammation, and dyslipidemia. In our study, apolipoprotein E knockout (ApoE-/-) and C57BL/6J mice were used as study groups. Water (WEP) and ethanolic extracts (EEP) of propolis were administered intraperitoneally to ApoE-/- and C57BL/6J mice modeled with a high-fat diet. Under anesthesia, the animals were euthanized by decapitation, and serum, along with aortic tissues, was collected. Serum total cholesterol (TC), triglyceride (TG), OxLDL and LOX-1 levels, OxLDL levels in aortic tissue homogenate, and subendothelial lipid accumulation levels by histological staining were determined in mice and statistical analyses were performed. WEP and EEP supplementation significantly decreased serum TC, TG, OxLDL, LOX-1, and tissue OxLDL levels and reduced plaque burden in the aortic root, with statistically significant differences observed. Those results suggest that propolis extracts have a potential treatment option for atherosclerosis, as a food supplement or a complementary medical/functional food. However, further research is needed to elucidate their molecular mechanisms, evaluate clinical efficacy and safety, and explore possible synergistic effects with existing atherosclerosis treatments.

Antioxidant Therapies as Emerging Adjuncts in Rheumatoid Arthritis: Targeting Oxidative Stress to Enhance Treatment Outcomes

Rheumatoid arthritis (RA) is a chronic autoimmune disorder characterized by persistent inflammation and progressive joint destruction. Recent data underscore oxidative stress as a primary factor in the pathophysiology of rheumatoid arthritis, intensifying inflammatory processes and tissue damage via the overproduction of reactive oxygen species (ROS) and compromised antioxidant defenses. Current therapies, including disease-modifying antirheumatic drugs (DMARDs), primarily target immune dysregulation but fail to address oxidative stress, necessitating novel adjunctive treatment strategies. This review explores the potential of antioxidant-based therapies as complementary approaches to RA management. Natural compounds such as curcumin, resveratrol, sulforaphane, and propolis exhibit strong anti-inflammatory and antioxidative properties by modulating redox-sensitive pathways, including nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) and nuclear factor erythroid 2-related factor 2(Nrf2)/heme oxygenase (HO-1). N-acetylcysteine (NAC) replenishes intracellular glutathione, enhancing cellular resilience against oxidative stress. Additionally, molecular hydrogen (H2) selectively neutralizes harmful ROS, reducing oxidative damage and inflammation. The role of vitamin supplementation (D, B12, C, and K) in regulating immune responses and protecting joint structures is also discussed. This review aims to evaluate the efficacy and potential clinical applications of antioxidant therapies in RA, emphasizing their role in mitigating oxidative damage and improving treatment outcomes. While preliminary findings are promising, further clinical trials are needed to establish standardized dosing, long-term safety, and their integration into current RA treatment protocols.

Structural characteristics of polysaccharide isolated from Potentilla anserina L. and its mitigating effect on Zearalenone-induced oxidative stress in Sertoli cells

The present study aims to characterize the structural features of a natural polysaccharide called PAP-1b extracted from the roots of Potentilla anserina L. and to evaluate its antioxidant activity. Structural characterization indicated that PAP-1b with a molecular weight of 1.22 × 104 Da was primarily composed of glucose and galactose. Methylation and NMR analyses showed that PAP-1b mainly consisted of →4)-α-D-Glcp-(1→, →4,6)-β-D-Glcp-(1→, →3,4)-α-Glcp-(1→ and α-D-Glcp-(1→). Subsequently, we evaluated the antioxidant activity of PAP-1b using zearalenone (ZEA)-induced oxidative stress in porcine Sertoli cells (SCs) as a model. Cellular experiments revealed that PAP-1b significantly attenuated ZEA-induced oxidative stress in SCs via the mitochondrial pathway, as evidenced by the increase in cell viability, the enhancement of antioxidant enzyme activities, and the reduction of reactive oxygen species (ROS), lactate dehydrogenase (LDH) and malondialdehyde (MDA) levels, as well as stabilization of the mitochondrial membrane potential and the reduction of apoptosis rate. These results suggest that Potentilla anserina L. polysaccharides can serve as a promising natural antioxidant for applications in the field of functional foods.

Pinocembrin reduces pyroptosis to improve flap survival by modulating the TLR4/NF-κB/NLRP3 signaling pathway

BACKGROUND

Pinocembrin has been widely utilized in clinical settings as a topical treatment for detoxification, inflammation reduction, and healing dermal conditions such as cracked skin and burns.

METHODS

In this study, pinocembrin was administered to hypoxia-reoxygenation model in human umbilical vein endothelial cells and 36 rats for 7 days using the McFarlane flap model. Neovascularization was then assessed using Doppler and lead oxide gelatin angiography. Neutrophil infiltration and mean microvessel density were assessed through hematoxylin and eosin staining. Immunofluorescence was employed to assess neovascularization and inflammation by detecting vascular endothelial growth factor, interleukin-1β, interleukin-6, and tumor necrosis factor-α. Pyroptosis was evaluated using western blot analysis.

RESULTS

Compared with the control group, the experimental groups exhibited a significant increase in flap survival area with the promotion of neovascularization, mitigation of oxidative stress, and suppression of pyroptosis and inflammation.

CONCLUSION

Pinocembrin enhanced flap survival, promoted neovascularization, mitigated oxidative stress, and suppressed pyroptosis and inflammation by downregulating the TLR4/NF-κB/NLRP3 signaling pathway.

Associations of composite dietary antioxidant index with premature death and all-cause mortality: a cohort study

Although previous evidence indicates that the composite dietary antioxidant index (CDAI) is negatively associated with health outcomes, no studies have explored the association between CDAI and premature death. This research utilized a cohort study design with 37,301 participants from the National Health and Nutrition Examination Survey (NHANES) from 2003 to 2018. Cox proportional hazard regression was employed to analyze the association between CDAI and premature death and all-cause mortality. Restricted cubic spline (RCS) analysis was performed to examine the nonlinear relationship between variables, and Kaplan-Meier analysis was used to evaluate survival outcomes over time. Sensitivity and subgroup analyses were conducted to assess the reliability of the findings. During a median follow-up period of 8.25 years, 4487 deaths were recorded, with 1671 classified as premature. The study revealed a negative correlation between CDAI and premature death (Per-SD hazard ratio [HR] 0.91, 95% CI 0.85-0.97; quartiles [Q4:Q1] HR 0.83, 95% CI: 0.70, 0.98) as well as all-cause mortality (Per-SD HR 0.96, 95% CI 0.92-1.00; quartiles [Q4:Q1] HR 0.91, 95%CI: 0.82, 1.01). The RCS analyses indicated a 'U' shaped relationship between CDAI and premature death and all-cause mortality. The threshold effect analysis pinpointed the inflection points for CDAI relative to premature death and all-cause mortality at 1.42 and 1.48, respectively. Kaplan-Meier curves illustrated that the likelihood of individual survival increases with higher CDAI quartiles. The results highlight the significance of dietary antioxidant intake in enhancing extending lifespan. Further research is needed to investigate the underlying mechanisms and determine optimal intake levels for improving health outcomes.

The role of Juniperus Macrocarpa extract as anti-inflammatory and antioxidant on methotrexate-induced acute liver injury in rat model

Background

Methotrexate (MTX) is an antifolate medication indicated to treat an array of tumors and autoinflammatory maladies. MTX may exhibit harmful impacts on multiple organs, especially liver injury and cirrhosis. Juniperus macrocarpa is a medicinal herb enriched with polyphenols and flavonoids featuring robust anti-inflammatory and antioxidative benefits.

Objective

To evaluate the hepatoprotective effects of Juniperus macrocarpa aqueous extract on MTX-aggravated liver toxicity.

Methods

The study involved 20 male middle-aged albino rats, arbitrarily allocated into 4 groups of 5 animals each. Group 1 (control) were given distilled water (DW) once daily for two weeks. Group 2 (MTX) got an intraperitoneal single dose of MTX (20 mg/kg) for two weeks. Rats in groups 3 and 4 were given daily dosages of 100 mg and 200 mg of Juniperus macrocarpa aqueous extract, respectively, for two weeks before receiving a single intraperitoneal MTX injection.

Results

Juniperus macrocarpa extracts at both low and high doses substantially alleviated the MTX-provoked biochemical alterations, as evidenced by decreased levels of inflammatory parameters including TNF-α and IL-6 and hepatic enzymes including ALT, AST, and ALP. Juniperus macrocarpa also significantly boosted levels of the anti-oxidant enzymes like SOD and GPX. Moreover, Juniperus macrocarpa extract attenuated congestive and degenerative hepatic changes, as indicated by improved histopathological findings.

Conclusion

The anti-oxidative and anti-inflammatory activities of Juniperus macrocarpa extract are a promising approach for ameliorating MTX-aggravated hepatotoxicity.

Chrysin Attenuates Gentamicin-Induced Renal Injury in Rats Through Modulation of Oxidative Damage and Inflammation via Regulation of Nrf2/AKT and NF-kB/KIM-1 Pathways

BACKGROUND

Gentamicin (GM) is extensively used as an antibiotic for the treatment of infections caused by Gram-negative bacteria. Oxidative stress and proinflammatory cytokines are implicated in GM-induced renal damage. Chrysin (CH), also known as 5,7-dihydroxyflavone, has been used in traditional medicine to treat various kidney disorders. The aim of this study was to investigate the antioxidant, anti-apoptotic, and anti-inflammatory effects of CH against nephrotoxicity induced by GM.

METHODS

Male rats were separated into four equal groups: a negative control group (NC), a CH-treated group (100 mg/kg/day per os), a group treated with GM (100 mg/kg/day IM), and a group treated with both GM and CH (100 mg/kg/day), for 10 days. Blood and urine renal markers were investigated.

RESULTS

GM caused increases in the serum creatinine and urea levels and decreases in creatinine clearance, urine flow, and urine volume in the GM-treated rats. Moreover, there were increases in the levels of IL-1β, TNF-α, IL-18, and MDA in the renal tissues, with an augmented expression of NF-κB/KIM-1, as well as decreases in antioxidant marker (GSH, GPx, CAT, and SOD) activities and decreased expressions of the anti-inflammatory transcription factors Nrf2 and AKT. The simultaneous treatment with CH in the GM-treated group protected renal tissues against the nephrotoxicity induced by GM, as demonstrated by the normalization of renal markers and improvement in histopathological damage.

CONCLUSIONS

This study reveals that CH may attenuate GM-induced renal toxicity in rats.

Apitherapy for diabetes mellitus: mechanisms and clinical implications

INTRODUCTION

Diabetes mellitus is a complex disease in terms of its causes and pathophysiological processes, it produces a significant impact on health and leads to complications that are difficult to manage.

CONTENT

This review summarizes and analyzes recent advances in the understanding of the mechanisms of diabetes mellitus and how apitherapy affects them. Also present the available clinical evidence on its application.

SUMMARY

Apitherapy (complementary-integral use of beehive products) is a potentially useful therapeutic system with a significant level of evidence. This review shows and analyzes the preclinical and clinical evidence on the use of apitherapy in diabetes mellitus.

OUTLOOK

Apitherapy shows significant effects on epigenetics, chronic inflammation, oxidative stress, metabolic control, dysbiosis, premature cell death and tissue remodeling. Clinical evidence shows an impact on these mechanisms. Apitherapy is a very useful complementary medicine in the treatment of diabetes mellitus.

Psoralen and Isopsoralen Activate Nuclear Factor Erythroid 2-Related Factor 2 Through Interaction With Kelch-Like ECH-Associated Protein 1

As natural furocoumarins, psoralen and its isomer isopsoralen are widely distributed in various fruits including Ficus carica L., vegetables including celery, and medicinal herbs including Psoralea corylifolia L. Although psoralen and isopsoralen have been used as dietary supplements because of their bioactivities such as antibacterial and anti-inflammatory properties; however, the potential mechanisms underlying the antioxidant activities of these two furocoumarins still need to be explored. Hence, the aims of this work were to examine the activation of nuclear factor erythroid 2-related factor 2 (Nrf2) by psoralen and isopsoralen, as well as the binding interaction of Kelch-like ECH-associated protein 1 (Keap1) with these two furocoumarins. Interestingly, both psoralen and isopsoralen induced Nrf2 nuclear translocation in a dose-dependent manner in HEK293T cells. These two furanocoumarins also activated antioxidant response element (ARE)-driven luciferase activity. The mRNA expression of GCLM, HO-1, and NQO1 genes was significantly upregulated by treatment of HEK293T cells with psoralen and isopsoralen, respectively. Similarly, the expression of proteins can be promoted. Both psoralen and isopsoralen were located in the top of the central pocket of the Keap1 Kelch domain, suggesting that they were natural ligands of Keap1. In conclusion, both psoralen and isopsoralen activate Nrf2 through interaction with Keap1, thereby serving as natural antioxidants.

Propolis extract nanoparticles alleviate diabetes-induced reproductive dysfunction in male rats: antidiabetic, antioxidant, and steroidogenesis modulatory role

Diabetes can affect male fertility via oxidative stress and endocrine system disruption. Nanomedicine based on natural products is employed to address diabetes complications. The current study aims to investigate the potential beneficial effect of propolis extract nanoparticles against diabetes-induced testicular damage in male rats. Sixty male rats were randomly allocated to six groups (n = 10). The first group served as a control group. The second and third received propolis extract (Pr) and propolis extract nanoparticles (PrNPs). The fourth group is the diabetic group that received streptozotocin (STZ) (55 mg kg/bwt) single-dose i/p. The fifth and sixth groups are diabetic rats treated with Pr and PrNPs. Both Pr and PrNPs were received at a dose (100 mg/kg bwt) orally. After 60 days, animals were euthanized, then pancreatic and testicular tissues were collected for redox status evaluation, gene expression analysis, and histopathological examination. Also, hormonal analysis (Insulin, total testosterone, and luteinizing hormone (LH) ) along with semen quality evaluation were done. Results showed that the induction of diabetes led to testicular and pancreatic redox status deterioration showing a reduction in reduced glutathione (GSH) as well as elevation of malondialdehyde (MDA), and nitric oxide (NO) levels. Also, relative transcript levels of testicular cytochrome P450 family 11 subfamily A member 1 (CYP11A1), 3β-Hydroxysteroid dehydrogenase (HSD-3β), and nuclear factor (erythroid-derived 2)-like 2 (NFE2L2) were significantly down-regulated, While the advanced glycation end-product receptor (AGER) relative gene expression was significantly upregulated. Furthermore, hormonal and semen analysis disturbances were observed. Upon treatment with Pr and PrNPs,  a marked upregulation of testicular gene expression of CYP11A1, HSD-3β, and NFE2L2 as well as a downregulation of AGER, was observed. Hormones and semen analysis were improved. In addition, the testicular and pancreatic redox status was enhanced. Results were confirmed via histopathological investigations. PrNPs outperformed Pr in terms of steroidogenesis pathway improvement, testicular antioxidant defense mechanism augmentation, and prospective antidiabetic activity.

Engineering an Escherichia coli strain for enhanced production of flavonoids derived from pinocembrin

BACKGROUND

Flavonoids are a structurally diverse group of secondary metabolites, predominantly produced by plants, which include a range of compounds with pharmacological importance. Pinocembrin is a key branch point intermediate in the biosynthesis of a wide range of flavonoid subclasses. However, replicating the biosynthesis of these structurally diverse molecules in heterologous microbial cell factories has encountered challenges, in particular the modest pinocembrin titres achieved to date. In this study, we combined genome engineering and enzyme candidate screening to significantly enhance the production of pinocembrin and its derivatives, including chrysin, pinostrobin, pinobanksin, and galangin, in Escherichia coli.

RESULTS

By implementing a combination of established strain engineering strategies aimed at enhancing the supply of the building blocks phenylalanine and malonyl-CoA, we constructed an E. coli chassis capable of accumulating 353 ± 19 mg/L pinocembrin from glycerol, without the need for precursor supplementation or the fatty acid biosynthesis inhibitor cerulenin. This chassis was subsequently employed for the production of chrysin, pinostrobin, pinobanksin, and galangin. Through an enzyme candidate screening process involving eight type-1 and five type-2 flavone synthases (FNS), we identified Petroselinum crispum FNSI as the top candidate, producing 82 ± 5 mg/L chrysin. Similarly, from a panel of five flavonoid 7-O-methyltransferases (7-OMT), we found pinocembrin 7-OMT from Eucalyptus nitida to yield 153 ± 10 mg/L pinostrobin. To produce pinobanksin, we screened seven enzyme candidates exhibiting flavanone 3-hydroxylase (F3H) or F3H/flavonol synthase (FLS) activity, with the bifunctional F3H/FLS enzyme from Glycine max being the top performer, achieving a pinobanksin titre of 12.6 ± 1.8 mg/L. Lastly, by utilising a combinatorial library of plasmids encoding G. max F3H and Citrus unshiu FLS, we obtained a maximum galangin titre of 18.2 ± 5.3 mg/L.

CONCLUSION

Through the integration of microbial chassis engineering and screening of enzyme candidates, we considerably increased the production levels of microbially synthesised pinocembrin, chrysin, pinostrobin, pinobanksin, and galangin. With the introduction of additional chassis modifications geared towards improving cofactor supply and regeneration, as well as alleviating potential toxic effects of intermediates and end products, we anticipate further enhancements in the yields of these pinocembrin derivatives, potentially enabling greater diversification in microbial hosts.

Synthesis and Bioevaluation of New Stable Derivatives of Chrysin-8-C-Glucoside That Modulate the Antioxidant Keap1/Nrf2/HO-1 Pathway in Human Macrophages

Background/Objectives: The beneficial effects of the flavonoid chrysin can be reduced by its poor oral bioavailability. It has been shown that chrysin-8-C-glucoside (1) has a better absorption capability. The aim of this study was to evaluate the antioxidant and anti-inflammatory activity of this glucoside, as well as the respective hexa-acetate derivative 1a and the hexa-ethyl carbonate derivative 1b since the inclusion of moieties in bioactive molecules may increase or modify their biological effects. Methods: THP-1 macrophages were used to determine the viability in the presence of chrysin derivatives, and non-cytotoxic concentrations were selected. Subsequently, lipopolysaccharide (LPS)-induced reactive oxygen species (ROS) production and inflammatory mediators were examined. The involvement of chrysin derivatives with the Keap1 and Nrf2 antioxidant system was determined by docking and Western blotting studies. Results: Our data demonstrated, for the first time, that pretreatment with the three compounds caused a significant reduction in LPS-induced reactive oxygen species (ROS) production and pro-inflammatory cytokines tumor necrosis factor alpha (TNF-α) and interleukin 1β (IL-1β) levels, as well as in cyclooxygenase 2 (COX-2) expression. The mechanisms underlying these protective effects were related, at least in part, to the competitive molecular interactions of these phenolic compounds with Kelch-like ECH-associated protein 1 (Keap1)-nuclear factor erythroid 2-related factor 2 (Nrf2), which would allow the dissociation of Nrf2 and its translocation into the nucleus and the subsequent up-regulation of hemo-oxygenase 1 (HO-1) expression. Conclusions: Compared to the 8-C-glucoside parent chrysin, compound 1a exhibited the strongest antioxidant and anti-inflammatory activity. We hypothesized that the incorporation of an acetate group (1a) may reduce its polarity and, thus, increase membrane permeability, leading to better pharmacological activity. These findings support the potential use of these phenolic compounds as Nrf2 activators against oxidative-stress-related inflammatory diseases.

Rapid Analysis of Colonic Metabolomics in High-Fat Diet Mice by Extraction Electrospray Ionization Mass Spectrometry (EESI-MS)

Propolis exhibits significant anti-inflammatory, antidiabetic, and antiobesity properties in both mouse models and clinical applications. However, the underlying metabolic mechanisms remain poorly understood. Traditional metabolomic methods that rely on chromatographic separation require complex preprocessing steps and extended detection periods. In this study, we employed extraction electrospray ionization mass spectrometry combined with multivariate analysis to directly profile metabolites in the colon tissue of mice. Our findings demonstrate the efficacy of ethanol extract of propolis (EEP) in mitigating weight gain, reducing inflammatory cytokines, and improving insulin resistance induced by a high-fat diet. Additionally, EEP enhanced glucose tolerance. Through collision-induced dissociation experiments, we identified 26 metabolites, with 4-hydroxyphenylacetic acid, protocatechuic acid, caffeic acid, ferulic acid, hippuric acid, histidine, and tryptophan emerging as potential biomarkers. Notably, tryptophan exhibited the highest content at 8.25 mg/g. Our research facilitates rapid profiling of colon metabolites, underscoring its significant potential for broader applications in animal metabolomic studies.

Galangin: A Promising Flavonoid for the Treatment of Rheumatoid Arthritis-Mechanisms, Evidence, and Therapeutic Potential

Rheumatoid Arthritis (RA) is a chronic autoimmune disease characterized by progressive joint inflammation and damage. Oxidative stress plays a critical role in the onset and progression of RA, significantly contributing to the disease's symptoms. The complex nature of RA and the role of oxidative stress make it particularly challenging to treat effectively. This article presents a comprehensive review of RA's development, progression, and the emergence of novel treatments, introducing Galangin (GAL), a natural flavonoid compound sourced from various plants, as a promising candidate. The bioactive properties of GAL, including its anti-inflammatory, antioxidant, and immunomodulatory effects, are discussed in detail. The review elucidates GAL's mechanisms of action, focusing on its interactions with key targets such as inflammatory cytokines (e.g., TNF-α, IL-6), enzymes (e.g., SOD, MMPs), and signaling pathways (e.g., NF-κB, MAPK), which impact inflammatory responses, immune cell activation, and joint damage. The review also addresses the lack of comprehensive understanding of potential treatment options for RA, particularly in relation to the role of GAL as a therapeutic candidate. It highlights the need for further research and clinical studies to ascertain the effectiveness of GAL in RA treatment and to elucidate its mechanisms of action. Overall, this review provides valuable insights into the potential of GAL as a therapeutic option for RA, shedding light on its multifaceted pharmacological properties and mechanisms of action, while suggesting avenues for future research and clinical applications.

Astragalin from Thesium chinense: A Novel Anti-Aging and Antioxidant Agent Targeting IGFR/CD38/Sirtuins

Astragalin (AG), a typical flavonoid found in Thesium chinense Turcz (T. chinense), is abundant in various edible plants and possesses high nutritional value, as well as antioxidant and antibacterial effects. In this study, we initially predicted the mechanism of action of AG with two anti-aging and antioxidant-related protein targets (CD38 and IGFR) by molecular docking and molecular dynamics simulation techniques. Subsequently, we examined the anti-aging effects of AG in Caenorhabditis elegans (C. elegans), the antioxidant effects in zebrafish, and verified the related molecular mechanisms. In C. elegans, AG synergistically extended the lifespan of C. elegans by up-regulating the expression of daf-16 through inhibiting the expression of daf-2/IGFR and also activating the AMPK and MAPK pathways to up-regulate the expression of sir-2.1, sir-2.4, and skn-1. In oxidatively damaged zebrafish embryos, AG demonstrated a synergistic effect in augmenting the resistance of zebrafish embryos to oxidative stress by up-regulating the expression levels of SIRT1 and SIRT6 within the zebrafish embryos system via the suppression of CD38 enzymatic activity and then inhibiting the expression of IGFR through high levels of SIRT6. These findings highlight the antioxidant and anti-aging properties of AG and indicate its potential application as a supplementary ingredient in aquaculture for enhancing fish health and growth.

Propolis as an autophagy modulator in relation to its roles in redox balance and inflammation regulation

Autophagy is a degradation process that is evolutionarily conserved and is essential in maintaining cellular and physiological homeostasis through lysosomal removal and elimination of damaged peptides, proteins and cellular organelles. The dysregulation of autophagy is implicated in various diseases and disorders, including cancers, infection-related, and metabolic syndrome-related diseases. Propolis has been demonstrated in various studies including many human clinical trials to have antimicrobial, antioxidant, anti-inflammatory, immune-modulator, neuro-protective, and anti-cancer. Nevertheless, the autophagy modulation properties of propolis have not been extensively studied and explored. The role of propolis and its bioactive compounds in modulating cellular autophagy is possibly due to their dual role in redox balance and inflammation. The present review attempts to discuss the activities of propolis as an autophagy modulator in biological models in relation to various diseases/disorders which has implications in the development of propolis-based nutraceuticals, functional foods, and complementary therapies.

Physicochemical Characterization, Antioxidant, and Proliferative Activity of Colombian Propolis Extracts: A Comparative Study

Propolis extracts have been widely studied due to their popularity in traditional medicine, presenting incredible biodiversity. This study aimed to analyze propolis extracts' phytochemical, physicochemical, and biological activities from four different biogeographic zones of the Huila region (Colombia). The raw material samples were collected by the scraping method and the ethanolic extracts (EEPs) were obtained by cold maceration with ethanol (96%). The physicochemical and sensory characterization was carried out according to the protocols recommended by the Brazilian Ministry of Agriculture and the main components of the EEPs were identified by LC-HRMS analysis. The determination of total phenols and flavonoids was carried out using colorimetric techniques. The antioxidant activity, cytotoxicity, and cell cycle regulation analyses in L929 and HGnF cells were evaluated using DPPH, Alamar Blue, and 7-amino actinomycin D (7-AAD) assays. The propolis samples presented an average yield of 33.1%, humidity between 1.6 and 2.8%, melting point between 54 and 62 °C, ashes between 1.40 and 2.19%, and waxes of 6.6-17.9%, respectively. The sensory characteristics of all samples were heterogeneous, complying with the quality specifications established by international standards. The polyphenolic and total flavonoid content was representative in the samples from Quebradon (255.9 ± 9.2 mg GAE/g, 543.1 ± 8.4 mg QE/g) and Arcadia (543.1 ± 8.4 mg GAE/g, 32.5 ± 1.18 g QE/g) (p < 0.05) that correlated with high antioxidant activity (Quebradon: 37.2 ± 1.2 µmol/g, Arcadia: 38.19 ± 0.7 µmol/g). In the chemical composition analysis, 19 compounds were characterized as phenolic acids and flavonoids, the most representative being chrysoeriol-O-methyl-ether, ellagic acid, and 3,4-O-dimethylcaffeic acid. Regarding biological activity, Quebradon and Arcadia propolis presented low toxicity with IC50 of 2.83 ± 2.3 mg/mL and 4.28 ± 1.4 mg/mL in HGnF cells, respectively, and an arrest of the cell cycle in the G2/M phase of 71.6% and 50.8% compared to the control (11.9%) (p < 0.05). In general, the results of this study contribute to the identification of valid quality criteria to evaluate Colombian propolis, contributing to its study and chemical and biological characterization as a source of raw material for industrial and pharmaceutical use. In addition, Quebradon and Arcadia propolis can be important sources of bioactive molecules for the development of new drugs.

Advances in Flavonoid Research: Sources, Biological Activities, and Developmental Prospectives

At present, the occurrence of a large number of infectious and non-communicable diseases poses a serious threat to human health as well as to drug development for the treatment of these diseases. One of the most significant challenges is finding new drug candidates that are therapeutically effective and have few or no side effects. In this respect, the active compounds in medicinal plants, especially flavonoids, are potentially useful compounds with a wide range of pharmacological activities. They are naturally present in nature and valuable in the treatment of many infectious and non-communicable diseases. Flavonoids are divided into fourteen categories and are mainly derived from plant extraction, chemical synthesis and structural modification, and biosynthesis. The structural modification of flavonoids is an important way to discover new drugs, but biosynthesis is currently considered the most promising research direction with the potential to revolutionize the new production pipeline in the synthesis of flavonoids. However, relevant problems such as metabolic pathway analyses and cell synthesis protocols for flavonoids need to be addressed on an urgent basis. In the present review, new research techniques for assessing the biological activities of flavonoids and the mechanisms of their biological activities are elucidated and their modes of interaction with other drugs are described. Moreover, novel drug delivery systems, such as nanoparticles, bioparticles, colloidals, etc., are gradually becoming new means of addressing the issues of poor hydrophilicity, lipophilicity, poor chemical stability, and low bioavailability of flavonoids. The present review summarizes the latest research progress on flavonoids, existing problems with their therapeutic efficacy, and how these issues can be solved with the research on flavonoids.

The Antioxidant and Anti-Inflammatory Effects of the Main Carotenoids from Tomatoes via Nrf2 and NF-κB Signaling Pathways

Oxidative stress and inflammation are crucial factors in the development of cardiovascular diseases. In previous research, the oxidative stress and inflammation models have frequently been explored independently. In the current study, we investigated the antioxidant and anti-inflammatory effects of tomato extract and its two main carotenoids (lutein and lycopene) with various concentrations using a rat cardiomyocyte model of co-existing oxidative stress and persistent chronic inflammation. It was discovered that the antioxidant effects of 0.5-5 μM lutein, 0.5-5 μM lycopene, and 50-200 μg/mL tomato extract increased in a dose-dependent manner. However, the pro-oxidation effects emerged by measuring the antioxidant-related indices, including the levels of ROS, SOD, and GPX in H9c2 cells as concentrations exceeded those mentioned above. The anti-inflammatory effects of lutein, lycopene, and tomato extract were simultaneously strengthened with higher concentrations, potentially due to the suppression of the NF-κB signaling pathway. Furthermore, high concentrations of lutein, lycopene, and tomato extract potentially regulated Nrf2/HO-1 and NF-κB signaling pathways dependent on TGF-1β and IL-10 to demonstrate high concentrations of pro-oxidation and anti-inflammation effects. Our findings indicate that the dose-effect regulatory mechanisms of antioxidant and anti-inflammatory properties among lutein, lycopene, and tomato extract will be advantageous in developing more effective therapeutic strategies to prevent cardiovascular diseases.

Phytochemicals from Anneslea fragrans Wall. and Their Hepatoprotective and Anti-Inflammatory Activities

Anneslea fragrans Wall., popularly known as "Pangpo tea", is an edible, medicinal, and ornamental plant of the Family Theaceae. The leaves of A. fragrans were historically applied for the treatment of liver and intestinal inflammatory diseases in China. This study aimed to explore the hepatoprotective agents from A. fragrans leaves through hepatoprotective and anti-inflammatory assessment. The phytochemical investigation of the leaves of A. fragrans resulted in the isolation and identification of a total of 18 chemical compounds, including triterpenoids, aliphatic alcohol, dihydrochalcones, chalcones, flavanols, phenolic glycoside, and lignans. Compounds 1-2, 4-6, 11-12, and 16-18 were identified from A. fragrans for the first time. Compounds 7 and 14 could significantly alleviate hepatocellular damage by decreasing the contents of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) and inhibit the hepatocellular apoptosis in the HepG2 cells induced by N-acetyl-p-aminophenol (APAP). In addition, compounds 7 and 14 inhibited reactive oxygen species (ROS) and malondialdehyde (MDA) contents and increased the catalase (CAT) superoxide dismutase (SOD), and glutathione (GSH) levels for suppressing APAP-induced oxidative stress. Additionally, compounds 7, 13, and 14 also had significant anti-inflammatory effects by inhibiting interleukin-6 (IL-6), interleukin-1β (IL-1β), and tumor necrosis factor-α (TNF-α) productions on LPS-induced RAW246.7 cells.

Anti-Inflammatory Potential of Seasonal Sonoran Propolis Extracts and Some of Their Main Constituents

Biological properties of Sonoran propolis (SP) are influenced by harvest time. Caborca propolis showed cellular protective capacity against reactive oxygen species, which might be implicated in anti-inflammatory effects. However, the anti-inflammatory activity of SP has not been investigated so far. This study investigated the anti-inflammatory activity of previously characterized seasonal SP extracts (SPE) and some of their main constituents (SPC). The anti-inflammatory activity of SPE and SPC was evaluated by measuring nitric oxide (NO) production, protein denaturation inhibition, heat-induced hemolysis inhibition, and hypotonicity-induced hemolysis inhibition. SPE from spring, autumn, and winter showed a higher cytotoxic effect on RAW 264.7 cells (IC₅₀: 26.6 to 30.2 µg/mL) compared with summer extract (IC₅₀: 49.4 µg/mL). SPE from spring reduced the NO secretion to basal levels at the lowest concentration tested (5 µg/mL). SPE inhibited the protein denaturation by 79% to 100%, and autumn showed the highest inhibitory activity. SPE stabilized erythrocyte membrane against heat-induced and hypotonicity-induced hemolysis in a concentration-dependent manner. Results indicate that the flavonoids chrysin, galangin, and pinocembrin could contribute to the anti-inflammatory activity of SPE and that the harvest time influences such a property. This study presents evidence of SPE pharmacological potential and some of their constituents.

Propolis consumption by asymptomatic HIV-individuals: Better redox state? A prospective, randomized, double-blind, placebo-controlled trial

Propolis is a natural product has many biological properties of clinical interest, such as anti-inflammatory and antioxidant. Considering that people living with HIV/aids (PLWHA) on effective combined antiretroviral therapy (cART) present early aging due to an intense immune activation, inflammation, and redox imbalance, propolis consumption could offer a benefit to such patients. This double-blind longitudinal study evaluated whether Brazilian green propolis pills intake (500 mg/day for three months) would decrease the oxidative stress of virological suppressed HIV-individuals. To compare each group (propolis, n = 20 versus placebo, n = 20) in both moments (M0, before and M1, after the intervention), the following markers were assessed: plasma malondialdehyde (MDA), carbonylation, total oxide nitric, total antioxidant capacity (TAP), superoxide dismutase, catalase, and NFkB and NRF2 gene expression. Data were analyzed using Poisson, Gamma distribution and ANOVA followed by Tukey-Kramer. The groups were homogeneous regarding age, gender, time of diagnosis/ treatment, cART scheme, CD4⁺ T cell count, and no changes were observed in the diet food, or patients' lifestyles. A decreased MDA concentration was seen in the propolis group (M0 = 0.24 ± 0.13, M1 = 0.20 ± 0.10 protein nmol/mg; p = 0.005) as well as a slight but non-significant increase of TAP (M0 = 49.07 ± 13.26, M1 = 52.27 ± 14.86%; p = 0.06). One may conclude that propolis promoted a lower lipid peroxidation and improved the antioxidant system, suggesting that its use may be beneficial to PLWHA in an attempt to contain the intense inflammatory and oxidant activity.

Propolis Ethanolic Extract Attenuates D-gal-induced C2C12 Cell Injury by Modulating Nrf2/HO-1 and p38/p53 Signaling Pathways

Previous study has shown that propolis ethanolic extract (PEE) has a protective effect on aging skeletal muscle atrophy. However, the exact molecular mechanism remains unclear. This study aimed to investigate the effect of PEE on D-galactose (D-gal)-induced damage in mouse C2C12 cells. The results revealed that PEE increased the viability of senescent C2C12 cells, decreased the number of senescence-associated β-galactosidase (SA-β-Gal)-positive cells and promoted the differentiation of C2C12 cells. PEE resisted oxidative stress caused by D-gal by activating the Nrf2/HO-1 signaling pathway and maintained the differentiation ability of C2C12 cells. PEE inhibited apoptosis by suppressing p38 phosphorylation and reducing p53 expression. In summary, our findings reveal the molecular mechanism by which PEE protects D-gal-induced C2C12 cells, providing a theoretical basis for the development of PEE for the alleviation of muscle atrophy.

Chrysin protects against cerebral ischemia-reperfusion injury in hippocampus via restraining oxidative stress and transition elements

Chrysin is a natural flavonoid compound that has antioxidant and neuroprotective effects. Cerebral ischemia reperfusion (CIR) is closely connected with increased oxidative stress in the hippocampal CA1 region and homeostasis disorder of transition elements such as iron (Fe), copper (Cu) and zinc (Zn). This exploration was conducted to elucidate the antioxidant and neuroprotective effects of chrysin based on transient middle cerebral artery occlusion (tMCAO) in rats. Experimentally, sham group, model group, chrysin (50.0 mg/kg) group, Ginaton (21.6 mg/kg) group, Dimethyloxallyl Glycine (DMOG, 20.0 mg/kg) + chrysin group and DMOG group were devised. The rats in each group were performed to behavioral evaluation, histological staining, biochemical kit detection, and molecular biological detection. The results indicated that chrysin restrained oxidative stress and the rise of transition element levels, and regulated transition element transporter levels in tMCAO rats. DMOG activated hypoxia-inducible factor-1 subunit alpha (HIF-1α), reversed the antioxidant and neuroprotective effects of chrysin, and increased transition element levels. In a word, our findings emphasize that chrysin plays a critical role in protecting CIR injury via inhibiting HIF-1α against enhancive oxidative stress and raised transition metal levels.

The protective activity of natural flavonoids against osteoarthritis by targeting NF-κB signaling pathway

Osteoarthritis (OA) is a typical joint disease associated with chronic inflammation. The nuclear factor-kappaB (NF-κB) pathway plays an important role in inflammatory activity and inhibiting NF-κB-mediated inflammation can be a potential strategy for treating OA. Flavonoids are a class of naturally occurring polyphenols with anti-inflammatory properties. Structurally, natural flavonoids can be divided into several sub-groups, including flavonols, flavones, flavanols/catechins, flavanones, anthocyanins, and isoflavones. Increasing evidence demonstrates that natural flavonoids exhibit protective activity against the pathological changes of OA by inhibiting the NF-κB signaling pathway. Potentially, natural flavonoids may suppress NF-κB signaling-mediated inflammatory responses, ECM degradation, and chondrocyte apoptosis. The different biological actions of natural flavonoids against the NF-κB signaling pathway in OA chondrocytes might be associated with the differentially substituted groups on the structures. In this review, the efficacy and action mechanism of natural flavonoids against the development of OA are discussed by targeting the NF-κB signaling pathway. Potentially, flavonoids could become useful inhibitors of the NF-κB signaling pathway for the therapeutic management of OA.

Evaluation of Chemical Composition, Sun Protection Factor and Antioxidant Activity of Lithuanian Propolis and Its Plant Precursors

The growing interest in polyphenols of natural origin and their plant sources encourages the study of their chemical composition and biological activity. Propolis is widely used as a source of phenolic compounds. The aim of this study is to evaluate and compare the chemical composition, antioxidant activity and sun protection factor (SPF) of the ethanolic extracts of the poplar buds, birch buds and pine buds of propolis plant precursors collected in Lithuania. The IC50 concentration of the extracts was evaluated using DPPH and ABTS methods. Extracts of poplar buds, birch buds and propolis showed a lower IC50 concentration by ABTS and DPPH methods compared with pine buds extracts. Poplar buds and propolis extracts showed the highest SPF value, while birch and pine buds extracts showed a lower SPF value. High-performance liquid chromatography (HPLC) analysis results showed that phenolic acids, such as p-coumaric acid and cinnamic acid, and flavonoids, such as pinobanksin and pinocembrin, were identified in all the tested extracts. Salicin has been identified only in poplar buds extracts. The results of antioxidant activity showed that propolis poplar and birch buds are a promising source of biologically active polyphenols.

Citrus junos Tanaka Peel Extract Ameliorates HDM-Induced Lung Inflammation and Immune Responses In Vivo

In the wake of the COVID-19 pandemic, lung disorders have become a major health concern for humans. Allergic asthma is the most prevalent form of asthma, and its treatments target the inflammation process. Despite significant developments in the diagnosis and management of allergic asthma, side effects are a major concern. Additionally, its extreme heterogeneity impedes the efficacy of the majority of treatments. Thus, newer, safer therapeutic substances, such as natural products, are desired. Citrus junos Tanaka has traditionally been utilized as an anti-inflammatory, sedative, antipyretic, and antitoxic substance. In this study, the protective effects of Citrus junos Tanaka peel extract (B215) against lung inflammation were examined, and efforts were made to understand the underlying protective mechanism using an HDM-induced lung inflammation murine model. The administration of B215 reduced immune cell infiltration in the lungs, plasma IgE levels, airway resistance, mucus hypersecretions, and cytokine production. These favorable effects alleviated HDM-induced lung inflammation by modulating the NF-κB signaling pathway. Hence, B215 might be a promising functional food to treat lung inflammation without adverse effects.