Griess Reaction Research Articles

Melissa officinalis Regulates Lipopolysaccharide-Induced BV2 Microglial Activation via MAPK and Nrf2 Signaling.

Neuroinflammation and microglial activation play critical roles in neurodegenerative diseases such as Alzheimer's and Parkinson's disease. Modulating microglial activation may help prevent the progression of these disorders. This study aimed to investigate the effects and mechanisms of Melissa officinalis ethanol extract on lipopolysaccharide (LPS)-induced microglial activation in BV2 cells. Cell viability and nitric oxide (NO) production were assessed using MTT assay and Griess reagent, while inflammatory cytokine levels were measured by qPCR. Key inflammatory pathways, including MAPK, TLR4, and antioxidant biomarkers, were analyzed through western blot and immunofluorescence. Rosmarinic acid content in M. officinalis was determined using high-performance liquid chromatography (HPLC). The results demonstrated that M. officinalis ethanol extract significantly inhibited LPS-induced NO production and reduced inflammatory cytokine expression. Additionally, it downregulated inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), TLR4, NF-κB, and MAPK signaling pathways (p38, JNK, ERK), while increasing the expression of antioxidant markers, including Nrf2, HO-1, catalase, and SOD2. In conclusion, M. officinalis ethanol extract exerts neuroprotective effects by modulating inflammation and enhancing antioxidant defenses, suggesting its potential in the prevention and treatment of inflammation-related neurodegenerative diseases.

Acute Chikungunya Infection Induces Vascular Dysfunction by Directly Disrupting Redox Signaling in Endothelial Cells.

Chikungunya virus (CHIKV) infection is characterized by febrile illness, severe joint pain, myalgia, and cardiovascular complications. Given that CHIKV stimulates reactive oxygen species (ROS) and pro- and anti-inflammatory cytokines, events that disrupt vascular homeostasis, we hypothesized that CHIKV induces arterial dysfunction by directly impacting redox-related mechanisms in vascular cells. Wild-type (WT) and iNOS knockout (iNOS-/-) mice were administered either CHIKV (1.0 × 106 PFU/µL) or Mock vehicle via the intracaudal route. In vivo, CHIKV infection induced vascular dysfunction (assessed by a wire myograph), decreased systolic blood pressure (tail-cuff plethysmography), increased IL-6 and IFN-γ, but not TNF-α levels (determined by ELISA), and increased protein content by Western blot. Marked contractile hyporesponsiveness to phenylephrine was observed 48 h post-infection, which was restored by endothelium removal. L-NAME, 1400W, Tiron, and iNOS gene deletion prevented phenylephrine hyporesponsiveness. CHIKV infection increased vascular nitrite concentration (Griess reaction) and superoxide anion (O2•-) generation (lucigenin chemiluminescence), and decreased hydrogen peroxide (H2O2, by Amplex Red) levels 48 h post-infection, alongside increased TBARS levels. In vitro, CHIKV infected endothelial cells (EA.hy926) and upregulated ICAM-1 and iNOS protein expression (determined by Western blot). These data support the conclusion that CHIKV-induced alterations in vascular ROS/NF-kB/iNOS/NO signaling potentially contribute to cardiovascular events associated with Chikungunya infection.

Stachys byzantina K. Koch (Lamiaceae) as a potential ingredient for delaying skin ageing and treating hyperpigmentation disorders in pharmaceutical products.

This study aimed to investigate whether the plant species Stachys byzantina produces bioactives with the potential to delay the skin ageing process and treat hyperpigmentation conditions. The antioxidant action was assessed by 2,2-diphenyl-1-picrylhydrazylradical scavenging, Griess reaction, oxygen radical absorption capacity, and β-carotene bleaching assays. Inhibitory activities for tyrosinase, hyaluronidase, and elastase enzymes were tested. The antiglycation activity, the sun protection factor (SPF), and the toxicity to skin cells by MTT(3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide)assay were also evaluated. The ethanolic extract of S. byzantina aerial parts and all fractions obtained by solvent partition inhibited the tyrosinase enzyme at different levels. The dichloromethane fraction (DF) demonstrated the highest inhibition (IC50 = 63.5±10.9 µg/ml). DF also inhibited the hyaluronidase enzyme with IC50 = 369±11.64 μg/ml and elastase by 40% at 500 μg/ml. This fraction showed prominent antioxidant and antiglycation activities, high SPF, and no cytotoxicity at concentrations lower than 50 μg/ml. The phenolic and flavonoid contents were 116.30±6.7 (mgTAE/g) and 66.38±13.5 (mgQE/g), respectively. Chlorogenic acid (23.54±2.46mg/g) and verbascoside (203.97±19.8mg/g) were identified and quantified. Stachys byzantina is a potential source of cosmetic and therapeutic ingredients to reduce hyperpigmentation and the impacts caused by free radicals, advanced glycation end products, and sun radiation in skin ageing.

<i>Oroxylum indicum</i> Kurz (L) leaf extract exerted antioxidant and anti-inflammatory effects on LPS-stimulated BV2 microglial cells

Purpose: To investigate the antioxidant and anti-inflammatory effects of Oroxylum indicum (L.) Kurz leaf extract on lipopolysaccharide (LPS)-activated BV2 microglia. Methods: BV2 cells were treated with LPS for 24 h in the presence or absence of Oroxylum indicum (O. indicum) leaf extract. The levels of reactive oxygen species (ROS), nitric oxide (NO), and interleukin 6 (IL-6) were quantified with CM-H2DCFDA, Griess reagent assay, and enzyme-linked immunosorbent assay (ELISA) test, respectively. The antioxidant activity of O. indicum leaf extract was assessed in vitro using DPPH, ABTS and FRAP assays. Results: Treatment with LPS resulted in significant increases in the levels of ROS, NO, and IL-6, when compared to untreated cells. However, co-treatment with O. indicum leaf extract significantly suppressed the production of these inflammatory markers (p < 0.05). In addition, the leaf extract of O. indicum exhibited antioxidant activity in the DPPH, ABTS, and FRAP assays. The contents of flavonoids and phenolics in O. indicum leaf extract were 13.25 ± 0.163 mg QE/g of dried extract and 82.58 ± 1.772 mg QE/g of dried extract, respectively (p < 0.05). Conclusion: The leaf extract of O. indicum exhibits anti-inflammatory and antioxidant properties in LPS-activated BV2 cells. This finding indicates that the leaf extract of O. indicum has promising potentials as a new source of herbal medication with anti- inflammatory properties. However, there is a need for more studies to unravel the fundamental mechanisms of their actions.

Proteomics fingerprinting reveals importance of iron and oxidative stress in Streptomyces scabies-Solanum tuberosum interactions.

The Gram-positive actinobacterium Streptomyces scabies is the major causal agent of potato common scab. The main pathogenicity factor is thaxtomin A, a phytotoxin that causes atypical cell death, although other secondary metabolites have been described to play a role in S. scabies virulence. Despite this, many aspects of the interaction between S. scabies and its primary host Solanum tuberosum L. remain to be elucidated. Intracellular proteins of S. scabies EF-35 grown in the presence of in vitro produced tubers (microtubers) of the Russet Burbank and Yukon Gold potato cultivars were extracted and analysed by electrospray mass spectrometry (ES MS/MS). Based on the results of proteomic analysis, iron quantification by ICP-MS and nitrite quantification using Griess reagent in growth media as well as RT-qPCR analysis of the siderophore pyochelin gene expression were performed in the presence and absence of microtubers. Hydrogen peroxide accumulation was also determined in the nutrient medium used for co-cultivation of bacteria and potato microtubers. Potato microtubers caused an increase in the content of bacterial proteins involved in stress and defense, secondary metabolism, and cell differentiation, as well as secreted proteins. Co-cultivation with potato microtubers induced the accumulation of S. scabies proteins implicated in siderophore pyochelin biosynthesis, nitrite production and oxidative stress perception and response. The increase in the abundance of proteins related to pyochelin biosynthesis was consistent with a significant decrease in the iron content in the culture medium, as well as with induction of expression of pyochelin biosynthesis genes. Elevated nitrite/sulfite reductase protein levels were associated with increased nitrite excretion by S. scabies cells in the presence of host microtubers. The increase in the levels of proteins associated with signaling and oxidative stress response could have been caused by the accumulation of ROS, in particular hydrogen peroxide, detected in the studied system. These findings show that interactions of S. scabies with living potato microtubers induce the production of secondary metabolites, defense responses, and protection from oxidative stress. This study suggests the importance of iron during host - S. scabies interactions, resulting in competition between pathogen and its host.

Spermidine attenuates chondrocyte inflammation and cellular pyroptosis through the AhR/NF-κB axis and the NLRP3/caspase-1/GSDMD pathway.

Osteoarthritis (OA) is a prevalent chronic degenerative disease, marked by a complex interplay of mechanical stress, inflammation, and metabolic imbalances. Recent studies have highlighted the potential of spermidine (SPD), a naturally occurring polyamine known for its anti-inflammatory and antioxidant properties, as a promising therapeutic agent for OA. This study delves into the therapeutic efficacy and mechanistic pathways of SPD in mitigating OA symptoms. Forty Sprague-Dawley rats were randomly assigned to four groups, including the CG (sham operation), model (anterior cruciate ligament transection [ACLT], and treatment (ACLT + two different doses of SPD) groups. In vivo, correlations between OA severity and different interventions were assessed by ELISA, X-rays, CT imaging, histological staining, and immunohistochemistry. In vitro, IL-1β was used to trigger chondrocyte inflammation, and SPD's cytotoxicity was assessed in primary rat chondrocytes. Next, inflammatory markers, extracellular matrix (ECM) proteins, and pathway marker proteins were detected in chondrocytes administered IL-1β alone, SPD, or aryl hydrocarbon receptor (AhR) silencing, by qRT-PCR, Griess reaction, ELISA, Western blot, and immunofluorescence. Morphological alterations and pyroptosis in chondrocytes were examined by transmission electron microscopy (TEM) and flow cytometry. Our research reveals that SPD exerts significant anti-inflammatory and antipyroptotic effects on IL-1β-treated chondrocytes and in anterior cruciate ligament transection (ACLT) rat models of OA, primarily through interaction with the Aryl hydrocarbon receptor (AhR). Specifically, SPD's binding to AhR plays a crucial role in modulating the inflammatory response and cellular pyroptosis by inhibiting both the AhR/NF-κB and NLRP3/caspase-1/GSDMD signaling pathways. Furthermore, the knockdown of AhR was found to negate the beneficial effects of SPD, underscoring the centrality of the AhR pathway in SPD's action mechanism. Additionally, SPD was observed to promote the preservation of cartilage integrity and suppress ECM degradation, further supporting its potential as an effective intervention for OA. Collectively, our findings propose SPD as a novel therapeutic approach for OA treatment, targeting the AhR pathway to counteract the disease's progression and highlighting the need for further clinical evaluation to fully establish its therapeutic utility.

Chebulinic acid isolated from aqueous extracts of Terminalia chebula Retz inhibits Helicobacter pylori infection by potential binding to Cag A protein and regulating adhesion.

Terminalia chebula Retz, known as the King of Tibet, is considered a functional food in China, celebrated for its antioxidant, immune-modulating, antibacterial, and anti-inflammatory properties. Chebulinic acid, derived from aqueous extracts of Terminalia chebula Retz, is known for its anti-inflammatory properties. However, its potential as an anti-Helicobacter pylori (HP) agent has not been fully explored. Herein, we extracted the main compound from Terminalia chebula Retz using a semi-preparative liquid chromatography (LC) system and identified compound 5 as chebulinic acid through Ultra-high performance liquid chromatography-MS/MS (UPLC-MS/MS) and Nuclear Magnetic Resonance (NMR). To evaluate its role, we conducted minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) assays, scanning electron microscope (SEM) imaging, inhibiting kinetics curves, urea fast test, cell counting kit-8 (CCK-8) assay, western blot analysis, griess reagent system, and molecular docking. Our results showed that chebulinic acid effectively inhibited the growth of the HP strain ATCC 700392, damaged the HP structure, and exhibited selective antimicrobial activity without affecting normal epithelial cells GES-1. Importantly, it suppressed the expression of Cytotoxin-associated gene A (Cag A) protein, a crucial factor in HP infection. Molecular docking analysis predicted a strong affinity (-9.7 kcal/mol) between chebulinic acid and Cag A protein. Overall, our findings suggest that chebulinic acid acts as an anti-adhesive agent, disrupting the adhesion of HP to host cells, which is a critical step in HP infection. It also suppresses the Cag A protein. These results highlight the potential of chebulinic acid against HP infections.

Lignans of Schisandra chinensis (Turcz.) Baill inhibits Parkinson's disease progression through mediated neuroinflammation-TRPV1 expression in microglia

BackgroundSchisandra chinensis (Turcz.) Baill (S. chinensis), a member of the Magnoliaceae family, is renowned for its distinctive medicinal attributes and is commonly employed in the treatment of disorders affecting the CNS. PurposeThe potential therapeutic effects of a lignan-enriched extract derived from Schisandra chinensis (Turcz.) Baill (LSC) on PD is assessed, which focuses on its mechanisms of action in addressing neuroinflammation. MethodsThe LSC has been obtained by purifying the ethyl alcohol extract of S. chinensis. The Orbitrap-MS method has been employed to analyze the chemical composition of the LSC. In LPS-induced BV2 cells, LSC-induced changes in M1/M2 type inflammatory cytokines have been examined using the Griess reaction, Elisa, JC-1, flow cytometry, IF, and WB methods. A model of PD has been established by treatment of MPTP in C57BL/6 mice. The effect of LSC on behavioral changes, inflammatory factor levels, expression of TH and IBA-1, and production of autophagy in the midbrain has been investigated by TEM, immunohistochemistry, Elisa, and WB. ResultsLSC has relieved sports injuries and pathological damage, and targeted the TRPV1-AMPK-NLRP3 signaling pathway, which affected neuroinflammation and autophagy in vivo. Furthermore, in vitro investigations demonstrated that LSC has activated M1/M2 transformation, its related inflammatory factors, and protein expressions of the NLRP3-Caspase1 signaling pathway in LPS-BV2 cells. The research notably demonstrated that the LSC promoted autophagy and suppressed inflammation through targeting TRPV1. ConclusionIn the investigation, LSC focused on TRPV1 and controlled neuroinflammation-autophagy by regulating AMPK-NLRP3, which has been proven for the first time. The study has presented molecular data supporting the use of LSC in treating PD and offers references for developing drugs. Remarkably, LSC has the potential to be utilized as a therapeutic or health medication that could significantly decrease PD.

Evaluation of antioxidant and anti-inflammatory properties, bioactive compound profiling, and molecular mechanisms of a multicomponent Thai herbal formulation

BackgroundMedicinal plants have long been used as dietary supplements to reduce the risk of chronic diseases, inflammation, cancer, and metabolic syndromes. Traditional remedies possess therapeutic properties, making them promising candidates for further investigation and potential pharmaceutical development. Aim of the studyThis study aimed to evaluate the efficacy of Belog Plus (BP), a polyherbal product containing five Thai medicinal plants: Citrus aurantifolia, Cannabis sativa, Tiliacora triandra, Alpinia galanga, and Piper nigrum, combined with safflower seed oil. This study focused on quantifying the total phenolic content (TPC) and total flavonoid content (TFC), and identifying key herbal biomarkers that contribute to its therapeutic properties. In addition to assessing the antioxidant and anti-inflammatory potential of the plant extracts, the study explored the molecular mechanisms underlying their anti-inflammatory activity, offering a comprehensive understanding of BP's efficacy. MethodsThe ethanolic extract of BP and its components were assessed for antioxidant potential using DPPH, FRAP, and H2O2 induced oxidative stress. The anti-inflammatory activity was evaluated using the Griess reaction assay, and the mechanisms were explored through mRNA and protein expression analysis. The TPC and TFC were measured using the Folin–Ciocalteu (F–C) assay and the aluminium chloride colorimetric assay, respectively, while herbal biomarkers were identified using LC-MS/MS analysis. ResultsThe results revealed that the ethanolic extract of BP (6.25-100 µg/ml) exhibited a potent anti-inflammatory effect through nitric oxide inhibition (IC50 24.4 μg/ml) and significantly reducing the expression of inflammatory genes iNOS, COX-2, IL-6, and TNF-α. Additionally, it significantly reduced the expression of inflammatory proteins iNOS and COX-2 at concentrations of 6.25-25 µg/ml. Among the individual components, C. aurantifolia, A. galanga, and P. nigrum showed potent anti-inflammatory effects with IC50 values of 35.7, 6.5, and 23.3 μg/ml, respectively. The TPC and TFC results demonstrated significant levels of phenolic (80.6 µg GAE/mg) and flavonoid (47.4 µg catechin/mg) compounds. Additionally, the LC-MS/MS analysis identified a variety of bioactive compounds known for their anti-inflammatory properties. ConclusionThese findings support BP's potential use as a dietary supplement to mitigate the risk of chronic inflammatory diseases, with its ethanolic extract containing bioactive phenolic and flavonoid compounds that significantly suppress iNOS and COX-2 protein expressions.

Isatidis Folium Represses Dextran Sulfate Sodium-Induced Colitis and Suppresses the Inflammatory Response by Inhibiting Inflammasome Activation

Background/Objectives: Isatidis Folium (IF) has been used in traditional medicine for various ailments, and recent research highlights its anti-inflammatory, antiviral, and detoxifying properties. This study investigated the anti-inflammatory effects of a hydroethanolic extract of IF (EIF) on inflammasomes and colitis. Methods: Dextran sulfate sodium (DSS)-induced colitis model C57BL/6 mice were treated with DSS, mesalamine, or EIF (200 mg/kg). Parameters such as daily disease activity index (DAI), spleen weight, colon length, and histopathology were evaluated. Intestinal fibrosis, mucin, and tight junction proteins were assessed using Masson’s trichrome, periodic acid–Schiff, and immunohistochemistry staining. RAW264.7 and J774a.1 macrophages were treated with EIF and lipopolysaccharide, with cell viability assessed via the cell counting kit-8 assay, nitric oxide (NO) production with Griess reagent, and cytokine levels with the enzyme-linked immunosorbent assay. NF-κB inhibition was analyzed using the luciferase assay, and phytochemical analysis was performed using UPLC-MS/MS. Results: EIF mitigated weight loss, reduced DAI scores, prevented colon shortening, and attenuated mucosal damage, fibrosis, and goblet cell loss while enhancing the tight junction protein occludin. The anti-inflammatory effects of EIF in RAW264.7 cells included reduced NO production, pro-inflammatory cytokines, and NF-κB activity, along with inhibition of NLRP3 inflammasome responses in J774a.1 cells. The key constituents identified were tryptanthrin, indigo, and indirubin. Conclusions: Animal studies demonstrated the efficacy of EIF in alleviating colitis, suggesting its potential for treating inflammatory diseases.

Iron chelating, antioxidant, and anti-inflammatory properties of brazilin from Caesalpinia sappan Linn

BackgroundIron overload and inflammation are severe conditions that can lead to various chronic diseases. However, the current iron chelator drugs have their limitations. The phytochemical compounds from herbals, such as brazilin, the major active compound in Caesalpinia sappan Linn., have significant therapeutic potential in various chronic diseases. Our study was designed to examine the effect of brazilin on iron chelating properties, antioxidant activity in hepatocytes, and anti-inflammatory potential in macrophages. MethodsThis study focused on the isolation, purification, and evaluation of brazilin, the principal bioactive constituent found in C. sappan wood. Brazilin was extracted via methanol maceration followed by column chromatography purification. The purified compound was characterized using high-performance liquid chromatography (HPLC), nuclear magnetic resonance (NMR) spectroscopy, and mass spectrometry (MS). The antioxidant potential of brazilin was assessed by in vitro assays, including 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azinobis-(3-ethylbenzthiazolin-6-sulfonic acid (ABTS), and ferric-reducing antioxidant power (FRAP). Furthermore, its cellular antioxidant activity was evaluated using hydrogen peroxide-induced oxidative stress in the hepatocellular carcinoma cell line (Huh-7). The iron-chelating capacity of brazilin was determined spectrophotometrically, and Job's plot method was used to elucidated the stoichiometry of the iron-brazilin complex formation. The anti-inflammatory properties of brazilin were investigated in lipopolysaccharide (LPS)-stimulated macrophages (RAW 264.7). Nitric oxide (NO) inhibition was quantified using the Griess reagent, while the expression levels of pro-inflammatory cytokines, interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α), were evaluated by RT-qPCR. ResultsThe results demonstrated that brazilin exhibited potent antioxidant activity in vitro and hepatocytes in a concentration-dependent manner. It also showed anti-inflammatory activity, in which NO production was significantly reduced and IL-6 and TNF-α expression in LPS-induced macrophages were repressed. Furthermore, it can bind ferric and ferrous ions. Brazilin acts as a bidentate iron chelator that forms a complex with iron in a 2:1 ratio, and two water molecules are used as additional chelators in this complex. ConclusionsOur findings have significant implications. Brazilin can potentially alleviate the harmful effects of iron-induced oxidative stress and inflammatory disorders.

Evaluation of Anti-Inflammatory Activity of the New Cardiotonic Steroid γ-Benzylidene Digoxin 8 (BD-8) in Mice.

Cardiotonic steroids are known to bind to Na+/K+-ATPase and regulate several biological processes, including the immune response. The synthetic cardiotonic steroid γ-Benzylidene Digoxin 8 (BD-8) is emerging as a promising immunomodulatory molecule, although it has remained largely unexplored. Therefore, we tested the immunomodulatory potential of BD-8 both in vitro and in vivo. Hence, primary mouse macrophages were incubated with combinations of BD-8 and the pro-inflammatory fungal protein zymosan (ZYM). Nitric oxide (NO) production was determined by Griess reagent and cytokines production was assessed by enzyme-linked immunosorbent assay. Inducible nitric oxide synthase (iNOS), reactive oxygen species (ROS), p-nuclear factor kappa B p65 (NF-κB p65), p-extracellular signal-regulated kinase (p-ERK), and p-p38 were evaluated by flow cytometry. Macrophages exposed to BD-8 displayed reduced phagocytic activity, NO levels, and production of the proinflammatory cytokine IL-1β induced by ZYM. Furthermore, BD-8 diminished the expression of iNOS and phosphorylation of NF-κB p65, ERK, and p38. Additionally, BD-8 exhibited anti-inflammatory capacity in vivo in a carrageenan-induced mouse paw edema model. Taken together, these findings demonstrate the anti-inflammatory activity of BD-8 and further reinforce the potential of cardiotonic steroids and their derivatives as immunomodulatory molecules.

CpG Oligodeoxynucleotide-Coated Chitosan Nanoparticles Enhance Macrophage Proinflammatory Phenotype In Vitro.

This study aimed to investigate the effects of CpG Oligodeoxynucleotide (CpG ODNs)-Coated Chitosan Nanoparticles (CNP) on the phenotype of murine macrophages and their pro-inflammatory cytokine profile in vitro. CNP-CpG ODNs loaded with FITC-scrambled siRNA were prepared using the ionotropic gelation method. Peritoneal macrophages were isolated and exposed to CNP-CpG ODNs. Treated macrophages were assessed for uptake capacity. Flow cytometry was used to evaluate the expression levels of MHC-II, CD40, and CD86 costimulatory molecules in treated macrophages. Furthermore, the secretion levels of proinflammatory cytokines (TNF-α and IL-6) and the release of nitric oxide (NO) were measured in the culture supernatant of treated macrophages using sandwich ELISA and the Griess reaction, respectively. These in vitro studies showed that CNP-CpG ODNs had no cytotoxic effect on macrophages and were efficiently taken up by them. Additionally, CNP-CpG ODNs significantly increased the production of TNF-α, IL-6, and NO in the culture supernatant compared to CNP alone. Moreover, CNP-CpG ODNs enhanced the expression of MHC-II, CD40, and CD86 costimulatory molecules on macrophages. These findings indicate that incorporating CpG ODNs into CNPs promotes macrophage maturation and a proinflammatory phenotype. Therefore, CNP-CpG ODNs may serve as an effective system for targeted gene delivery to macrophages, enhancing immune responses.

Modulation of M1/M2 Cytokines and Inflammatory Enzymes by Persicaria Species Leaf Extracts in Lipopolysaccharide-stimulated RAW 264.7 Cell Macrophages.

Investigating the impacts of plant-based substances on the regulation of pro-inflammatory M1 and anti-inflammatory M2 cytokines could have significant implications for immune-related health conditions. Seven Persicaria plant species from sub-Saharan Africa were specifically selected for analysis, based on their traditional use in treating inflammation. To investigate the inhibitory effects of methanol leaf extracts from selected plants on enzymes involved in chronic inflammation. The inhibition of nitric oxide production, acetylcholinesterase activity, and 15-lipoxygenase activity was assessed using the Griess reagent method, Ellman's colorimetric method, and the ferrous oxidation-xylenol orange assay. The quantity of M1/M2 cytokines released was quantified using a flow cytometer. At a concentration of 50 µg/mL, the methanol extracts of P. limbata exhibited the highest NO inhibition (97.67%), followed by P. nepalensis (93.06%) and P. setosula (92.78%). The NO inhibition caused by the plant extracts was correlated directly with the decrease in NO release by the LPS-stimulated macrophages. Furthermore, the pro-inflammatory enzyme assays indicated that the methanol extracts of P. setosula exhibited the highest enzyme inhibitory activity (LOX 89.59%, AChE 72.12 %). This was followed by P. limbata (with 92.76% for LOX and 56.93% for AChE) and P. nepalensis (with 88.16% for LOX and 47.17% for AChE). Cytokine assays revealed that the extracts of P. limbata had significant dose-dependent suppressive effects on IFN-γ and TNF-α expression while promoting the secretion of IL-2, IL-4, IL-6, and IL-10. Extracts of P. limbata contain immunomodulatory compounds that could be further explored as potential remedies to target the molecular drivers of chronic inflammation.

Potential active fractions and constituents in the flowers of Trollius chinensis Bunge responsible for treating acute pharyngitis

Ethnopharmacological relevanceTrollius chinensis Bunge has a long history of use in China as traditional Chinese medicine and functional tea for the treatment of respiratory infections, such as pharyngitis, tonsillitis and bronchitis. Pharyngitis can impact the entire throat and adjacent lymphoid tissues, and may lead to significant systemic complications. However, the active components and mechanism of Trollius chinensis Bunge for treating acute pharyngitis remains unclear. Aim of the studyTrollius chinensis Bunge is recognized in China both as a medicinal herb and a functional tea. Research into its properties aimed to establish its effectiveness against pharyngitis and to pinpoint the active components and mechanism. Materials and methodsA 70% ethanol extract from the herb was prepared, which was refined using chromatography through a column containing D101 macroporous resin and varying ethanol solutions. The efficacy of the initial and refined extracts was tested using a rat model of ammonia-induced acute pharyngitis. Pathological examination, HE staining and ELISA were applied to screen activity fraction. The compounds were isolated by silica gel, sephadex LH-20 column chromatography and semi-preparative HPLC chromatography from active fraction. All of the isolated compounds were assessed for anti-inflammatory activity by acting on LPS-induced RAW 264.7 macrophage cells in vitro. Cytotoxicity of compounds was detected by CCK-8 assay. The Griess reaction was applied to evaluate the inhibitory effects of isolated compounds on NO production in RAW 264.7 cells induced by LPS. TNF-α, IL-6, IL-1β and PGE2 levels in macrophage supernatant were detected by ELISA. Molecular docking and western blot analysis were applied to study the anti-inflammatory mechanism of active compound. ResultsThe fraction extracted with 30% ethanol proved particularly effective, significantly reducing pharyngitis symptoms. This was evidenced by decreased levels of cytokines (TNF-α, IL-6, IL-1β and PGE2) and visible improvements in the pharyngeal tissue histology. In pursuit of pharyngitis treatments, 23 phenolic acids and 13 flavonoids were isolated from the 30% ethanol fraction and identified using spectral analysis. Of these, three were newly discovered compounds and eight were first-time isolates from the Trollius genus. These compounds were further investigated for their ability to suppress nitric oxide production in RAW 264.7 cells triggered by lipopolysaccharide. Compounds 3, 19, and 26 exhibited strong anti-inflammatory properties. HPLC analysis of the 30% ethanol fraction revealed that orientin was the predominant component, accounting for 44.4% of this fraction. Western blot analysis demonstrated that orientin reduced the expression levels of the protein p-p65 relative to p65, p-IκBα relative to IκBα and iNOS, indicating an anti-inflammatory effect potentially through the modulation of the NF-κB signaling pathway. ConclusionThe finding of this study provided strong support for the use of T. chinensis as a potential functional food for treating pharyngitis.

Phytochemical-Based Nanoantioxidants Stabilized with Polyvinylpyrrolidone for Enhanced Antibacterial, Antioxidant, and Anti-Inflammatory Activities.

Despite the inhibitory effect of phytoncide (Pht) on food-borne pathogenic bacterial growth, the hydrophobic nature and susceptibility to biodegradation under physiological conditions limits its applications. Here, we developed Pht-loaded polyvinylpyrrolidone (PVP) micelles (Pht@PVP MC) via micelle packing. Pht was solubilized using different types of PVP as micellar vehicles. The as-prepared Pht@PVP MCs were characterized using dynamic light scattering and transmission electron microscopy. The sizes of the Pht@PVP MCs were controlled from 301 ± 51 to 80 ± 3 nm by adjusting the PVP content. The polydispersity index of Pht@PVP MC was between 0.21 ± 0.03 and 0.16 ± 0.04, indicating homogeneous size. A colony-counting method was employed to evaluate the improvement in antibacterial activity after Pht encapsulation in PVP micelles. The reactive oxygen species (ROS)-scavenging activity and anti-inflammatory efficacy of Pht@PVP MC were analyzed in a concentration range of 10-100 μg/mL by evaluating in vitro ROS and nitric oxide levels using DCFDA and Griess reagents. PVP with both hydrophobic and hydrophilic moieties improved the aqueous solubility of Pht and stabilized it via steric hindrance. Higher-molecular-weight PVP at higher concentrations resulted in a smaller hydrodynamic diameter of Pht@PVP MC with uniform size distribution. The spherical Pht@PVP MC maintained its size and polydispersity index in a biological buffer for 2 weeks. Pht@PVP MC exhibited enhanced antibacterial activity compared to bare Pht. The growth of Staphylococcus aureus was effectively inhibited by Pht@PVP MC treatment. Furthermore, biocompatible Pht@PVP MC exhibited dose-dependent antioxidant and anti-inflammatory activities in vitro. Overall, Pht@PVP MC is an effective alternative to synthetic antibacterial, antioxidant, and anti-inflammatory chemicals.

Total Phenolic and Flavonoid Contents, Antioxidant, Antibacterial and Anti-Inflammatory Activities and Toxicities of Ethanol Extracts from Curcuma Mangga, Zingiber Officinale and Zingiber Montanum

The objectives of this study were to determine and to compare total phenolic and flavonoid contents (TPC and TFC), antioxidant, antibacterial and anti-inflammatory activities and toxicities of ethanol extracts from Curcuma mangga, Zingiber officinale and Zingiber montanum. The study was performed by determinations of 1) TPC using Folin-Ciocalteu reagent method and TFC using colorimetric method of aluminum chloride, 2) antioxidant activities using DPPH, ABTS and FRAP assay, 3) antibacterial activities through evaluation inhibition of bacterial growth, MIC and MBC against Bacillus cereus, Bacillus subtilis, Escherichia coli, and Staphylococcus aureus, 4) anti-inflammatory activity using Griess reaction to measure nitric oxide (NO) production in LPS-stimulated RAW 264.7 macrophage cells and 5) toxicities using lethality assay in brine shrimps and MTT assay in the RAW 264.7 cells. The results revealed that all the extracts possess TPC and TFC, antioxidant, antibacterial and anti-inflammatory activities which the highest TPC and TFC and strongest activities were found in the Z. montanum extract. However, the extracts showed mildly to moderately toxic to brine shrimps, consider to Artemia salina nauplii, and nontoxic to the RAW 264.7 cells. And also, the results confirm the utilization of these extracts for the treatment and/or management of diseases that related to antioxidant, antibacterial and anti-inflammatory activities.

Eriodictyol attenuates osteoarthritis progression through inhibiting inflammation via the PI3K/AKT/NF-κB signaling pathway

Eriodictyol, a flavonoid distributed in citrus fruits, has been known to exhibit anti-inflammatory activity. In this study, destabilized medial meniscus (DMM)-induced OA model was used to investigate the protective role of eriodictyol on OA. Meanwhile, we used an IL-1β-stimulated human osteoarthritis chondrocytes model to investigate the anti-inflammatory mechanism of eriodictyol on OA. The production of nitric oxide was detected by Griess reaction. The productions of MMP1, MMP3, and PGE2 were detected by ELISA. The expression of LXRα, ABCA1, PI3K, AKT, and NF-κB were measured by western blot analysis. The results demonstrated that eriodictyol could alleviate DMM-induced OA in mice. In vitro, eriodictyol inhibited IL-1β-induced NO, PGE2, MMP1, and MMP3 production in human osteoarthritis chondrocytes. Eriodictyol also suppressed the phosphorylation of PI3K, AKT, NF-κB p65, and IκBα induced by IL-1β. Meanwhile, eriodictyol significantly increased the expression of LXRα and ABCA1. Furthermore, eriodictyol disrupted lipid rafts formation through reducing the cholesterol content. And cholesterol replenishment experiment showed that adding water-soluble cholesterol could reverse the anti-inflammatory effect of eriodictyol. In conclusion, the results indicated eriodictyol inhibited IL-1β-induced inflammation in human osteoarthritis chondrocytes through suppressing lipid rafts formation, which subsequently inhibiting PI3K/AKT/NF-κB signaling pathway.

Development of a simple and rapid dipstick paper-based test strip for colorimetric determination of nitrate and nitrite in water and foodstuffs

A rapid user-friendly paper-based test strip using zinc microparticles in conjugation with Griess reagent was developed for nitrite and nitrate detection. Test strips were fabricated using a simple and fast method of step-by-step immersion into reagents so that each strip contained a single detection pad for nitrite detection and another separate pad for nitrate detection. To reduce nitrate to nitrite, zinc microparticles suspended in ethanolic solution of polyvinylpyrrolidone (PVP) were uniformly immobilized on the paper strips that were previously impregnated in the Griess reagent and dried. The Griess reagent components were optimized to reach the highest color intensity. The optimized test strip was able to determine both nitrite and nitrate with respective detection limits of 0.43 and 9.43 mg/kg and a detection time of 60 s. The performance of the new test strips was evaluated for the simultaneous colorimetric detection of nitrite and nitrate in water and different food samples.

Reduction with zinc — Impact on the determination of nitrite and nitrate ions using microfluidic paper-based analytical devices

We used a microfluidic paper-based analytical device (μPAD) to investigate the influence that zinc reduction exerts on the determination of nitrite and nitrate ions in natural water samples. The μPAD consists of layered channels for the reduction of nitrate to nitrite with zinc powder and the subsequent detection of nitrite with Griess reagent. The amount of zinc, number of layers, and reaction time for the reduction were optimized to obtain an intense signal for nitrate. Initially, the sensitivity to nitrate corresponded to 55% that of nitrite, which implied an incomplete reduction. We found, however, that zinc decreased the sensitivity to nitrite in both the μPAD and spectrophotometry. The sensitivity to nitrite was decreased by 48% in spectrophotometry and 68% in the μPAD following the reaction with zinc. One of the reasons for the decreased sensitivity is attributed to the production of ammonia, as we elucidated that both nitrite and nitrate produced ammonia via the reaction with zinc. The results suggest that the total concentration of nitrite and nitrate must be corrected by constructing a calibration curve for nitrite with zinc, in addition to developing curves for nitrate with zinc and for nitrite without zinc. Using these calibration curves, the absorbance at different concentration ratios of nitrite and nitrate ions could be reproduced via calculation using the calibration curves with zinc for nitrite and nitrate. Eventually, the developed μPAD was applied to the determination of nitrite and nitrate ions in natural water samples, and the results were compared with those using a conventional spectrophotometric method. The results of the μPAD are in good agreement with those of conventional spectrophotometry, which suggests that the μPAD is reliable for the measurement of nitrite and nitrate ions in natural water samples.