Inhibition Of NO Production Research Articles

Four new phenolic constituents from root barks of Paeonia ostii

The Paeonia ostii, also known as "Feng Dan" have a crucial role in folk medicine to treat lumbar muscles strain, knee osteoarthritis and cervical spondylosis. In this study, four new phenolic compounds, specifically Paeoniaostiph A–E (1–4) phenolic compounds were characterised through spectroscopic techniques, including 1D and 2D NMR, HRESIMS, UV, IR, and electronic circular dichroism computations to explore their structures. Cytotoxicity and NO production inhibition of the new phenolic compounds were also studied. The results of the cytotoxicity experiment showed that compound 1 is cytotoxic to two human cancer cell lines with IC50 values ranging from 13.3 to 13.5 μM. Compounds 1 and 2 showed certain inhibitory activity on NO production. This is the first report on isolating the components from natural sources.

Anti-Inflammatory, Antidiabetic, and Antioxidant Properties of Extracts Prepared from Pinot Noir Grape Marc, Free and Incorporated in Porous Silica-Based Supports.

This study presents properties of hydroethanolic extracts prepared from Pinot Noir (PN) grape pomace through conventional, ultrasound-assisted or solvothermal extraction. The components of the extracts were identified by HPLC. The total content of polyphenols, flavonoids, anthocyanins, and condensed tannins, as well as antioxidant activity and α-glucosidase inhibitory activity of extracts were evaluated using UV-vis spectroscopy. All extracts were rich in phenolic compounds, proving a good radical scavenging activity. The extract obtained by conventional extraction at 80 °C showed the best α-glucosidase inhibitory activity close to that of (-)-epigallocatechin gallate. To improve the chemical stability of polyphenols, the chosen extract was incorporated in porous silica-based supports: amine functionalized silica (MCM-NH2), fucoidan-coated amine functionalized silica (MCM-NH2-Fuc), MCM-41, and diatomite. The PN extract exhibited moderate activity against Gram-positive S. aureus (MIC = 156.25 μg/mL) better than against Gram-negative E. coli (MIC = 312.5 μg/mL). The biocompatibility of PN extract, free and incorporated in MCM-NH2 and MCM-NH2-Fuc, was assessed on RAW 264.7 mouse macrophage cells, and the samples showcased a good cytocompatibility at 10 µg/mL concentration. At this concentration, PN and PN@MCM-NH2-Fuc reduced the inflammation by inhibiting NO production. The anti-inflammatory potential against COX and LOX enzymes of selected samples was evaluated and compared with that of Indomethacin and Zileuton, respectively. The best anti-inflammatory activity was observed when PN extract was loaded on MCM-NH2-Fuc support.

Preparation, typical structural characteristics and relieving effects on osteoarthritis of squid cartilage type II collagen peptides

The promoting effects of collagen and its derivatives on bone health have been uncovered. However, the structure and effects of type II collagen peptides from squid cartilage (SCIIP) on osteoarthritis still need to be clarified. In this study, SCIIP was prepared from squid throat cartilage with pretreatment by 0.2 mol/L NaOH at a liquid–solid ratio of 10:1 for 18 h and hydrolyzation using alkaline protease and flavourzyme at 50 °C for 4 h. The structure of SCIIP was characterized as a molecular weight lower than 5 kDa (accounting for 87.7 %), a high glycine level of 35.0 %, typical FTIR and CD features of collagen peptides, and a repetitive sequence of Gly–X–Y. GP(Hyp)GPD and GPAGP(Hyp)GD were separated and identified from SCIIP, and their binding energies with TLR4/MD-2 were − 8.4 and − 8.0 kcal/mol, respectively. SCIIP effectively inhibited NO production in RAW264.7 macrophages and alleviated osteoarthritis in rats through the TLR4/NF-κB pathway. Therefore, SCIIP exhibited the potential for application as an anti-osteoarthritis supplement.

IN VITRO AND IN SILICO INHIBITORY ACTIVITY OF ANGIOTENSIN-CONVERTING ENZYME II AND ANTI-INFLAMMATORY EFFECTS OF NATURAL COMPOUNDS FROM RHEUM OFFICINALE ROOTS

Rhubarb roots (Rheum officinale), a common medicinal plant in folk remedies, and their chemical compositions were investigated for their inhibitory activity of angiotensin-converting enzyme II and anti-inflammatory effects by inhibiting NO production and IL-6 expression. Four natural compounds, including two anthraquinones, chrysophanol (2) and emodin (3), and two stilbenes, rhapontigenin (1) and trans-piceatannol (4), were isolated from the roots of Rhubarb. The results showed that rhapontigenin (1) exhibited an inhibitory effect on the ACE-2 enzyme with an IC50 value of 132 mM. In an in silico study, rhapotigenin (1) had a binding energy value of -9.32 kcal/mol, lower than MLN-4760, on ACE-2. Both rhapontigenin (1) and emodin (3) exhibited inhibitory activity on NO production in primary cultures of macrophages RAW264.7, with IC50 values ranging from 5.65 to 32.3 µg/mL. This is the first study of the anti-ACE-2 and anti-inflammatory activity of Rhubarb root extract and its constituents.

Pipersarmenoids, new amide alkaloids from Piper sarmentosum

A chemical investigation of the aerial parts of Piper sarmentosum resulted in the isolation and identification of 14 amide alkaloids, including three new amide alkaloids, pipersarmenoids A − C (1–3), three new natural amide alkaloids, pipersarmenoids D − F (4–6), and 8 known analogues, N-p-coumaroyltyramine (7), piperlotine C (8), piperlotine D (9), pellitorine (10), sarmentine (11), aurantiamide acetate (12), 1-cinnamoyl pyrrolidine (13) and sarmentamide B (14). Their structures were determined by spectroscopic analysis including HRESIMS and 1D and 2D NMR. The cytotoxicity, neuroinflammation-inhibiting and acetylcholinesterase (AChE) inhibitory activities of those compounds were tested. Compounds 1, 2 and 12 inhibited NO production induced by LPS in BV2 cells with IC50 values of 9.36, 12.53 and 10.77 μM, respectively. Moreover, 1, 2, 7 and 11 showed moderate inhibitory activity on AChE with IC50 values ranging from 37.56 to 48.84 μM.

Phytochemical profiling and therapeutic potential of Baliospermum montanum: A promising inhibitor of COX-2/15-LOX enzymes and NO production in LPS-stimulated RAW 264.7 macrophages

IntroductionBaliospermum montanum (BM) is traditionally used to treat various ailments such as inflammation, rheumatoid arthritis, pain, etc. The root part of BM is well documented for its anti-inflammatory activity. However, the present study evaluates the multitargeted anti-inflammatory activity of the less explored BM leaf part. This is the first study investigating the COX-2, 15-LOX dual inhibiting potential and NO production inhibition of BM leaf extracts, fractions and compounds. MethodsThe BM leaf's water, ethanol, and hydroethanolic extracts were evaluated for anti-inflammatory activity by assessing the inhibition of COX-2, 15-LOX, and NO production. Additionally, the antioxidant potential of the extracts was determined through DPPH, ABTS, and FRAP assays. The most active ethanol extract was fractionated into 12 fractions and tested for anti-inflammatory, antioxidant, phenol and flavonoid content. Compounds were isolated from the most active fractions and identified using NMR techniques. The isolated compounds were checked for their anti-inflammatory activity. In addition, HPLC analysis of ethanol extract, fractions, and isolated compounds was carried out. ResultsThe ethanol extract exhibited higher inhibition of COX-2, 15-LOX enzymes and NO production (IC50 35.75 ± 1.95 μg/mL) in LPS-treated RAW 264.7 cells. It also showed higher antioxidant activity. Following the fractionation of the ethanol extract using different solvents, only the ethyl acetate fractions demonstrated inhibition of COX-2, 15-LOX enzymes, and NO production. The ethyl acetate and acetone fractions are excellent sources of antioxidants, phenolic and flavonoid compounds. An effort to find the active principles from these ethyl acetate fractions resulted in the isolation and identification of four potent anti-inflammatory agents, namely, (-)-epiafzelechin, afzelechin-(4α→8)-afzelechin, afzelechin-(4α→8)-epiafzelechin and β-sitosterol-d-glycoside. The first three compounds were reported for the first time from this plant and afzelechin-(4α→8)-afzelechin was found to be a potent inhibitor of the COX-2/15 LOX enzyme as well as NO production (IC50 = 5.9 ± 1.09 µM). ConclusionBased on these findings, we conclude that ethanol extract, fractions, and isolated compounds exert anti-inflammatory activity through multiple therapeutic mechanisms. The present study scientifically supports the traditional use of plant BM for treating inflammation and other related disorders.

Naturally occurring benzophenones and xanthones from Garcinia smeathmannii (Planch. & Triana) Oliv. displayed anti-inflammatory effects by modulating the activities of inflammatory mediators in LPS-stimulated RAW 264.7 macrophages.

Introduction: There is a growing interest in studying natural products for the identification of novel lead compounds for drug development for treating inflammatory diseases. Although some studies have focused anti-inflammatory activity of benzophenones and xanthones, exploring additional targets such as enzymes and cytokines, involved in their inflammatory response could provide more comprehensive understanding of the compounds' anti-inflammatory effects. In this study, four xanthones ananixanthone (1), smeathxanthone A (2), smeathxanthone B (3), and 1,3,5,8-tetrahydroxy-2-(3-methybut-2-enyl)-4-(3,7-dimethyloct-2,6-dienyl) xanthone (4); and three benzophenones guttiferone O (5), guttiferone M (6), and aristophenone A (7) from Garcinia smeathmannii (Planch. & Triana) Oliv. were investigated for their effect on nitric oxide production, cyclooxygenase, lipoxygenase inhibition, and Th1/Th2 cytokines production in activated RAW 264.7 macrophages. Methods: The Griess reagent method and the ferrous oxidation-xylenol orange assay were used to evaluate the inhibition of NO production and the 15-lipoxygenase activity respectively. Cyclooxygenase activity was assessed using the fluorometric COX activity assay kit and measurement of Th1/Th2 cytokines was performed using a flow cytometer. Results: All the tested compounds exhibited a dose-dependent inhibition of NO production with varying degrees of inhibitory effects on 15-LOX activity. Compound (6), displays the best inhibitory effect on COX-1/COX-2 activity. A general trend of the tested compounds on cytokines profiles revealed that compound (5) showed a pronounced enhancement of anti-inflammatory cytokines (IL-4 and IL-10). Conclusion: This observation supports future exploration of ananixanthone (1), guttiferone O (5), and guttiferone (6) as potential candidates for the development of anti-inflammatory drugs.

Undescribed steroidal alkaloids from the bulbs of Fritillaria ussuriensis Maxim and their anti-inflammatory activities

In total, 16 undescribed steroidal alkaloids (1–16), along with nine known ones (17–25), were isolated from the bulbs of Fritillaria ussuriensis Maxim. Among the undescribed compounds mentioned, compounds 1–6, 8 bearing an 16β-hydroxy substituent, as well as compounds 13 and 14 exhibited an unusual seven-membered skeleton. Their structures were established based on extensive spectroscopic analyses, including HRESIMS and NMR (1D and 2D), and comparison with the data reported in the literature. Furthermore, all the compounds were evaluated for their anti-inflammatory effect on the NO production of LPS-stimulated RAW264.7 cells. Compounds 1, 4, 11, 15, 22 and 24 could significantly inhibit NO production with IC50 values below 10 μM.

Tetrahydroxanthene-1,3(2H)-diones and Oxidized Hexadiene Derivatives from Uvaria leptopoda and Their Biological Activities.

The first phytochemical investigation of the twig extract of Uvaria leptopoda resulted in the isolation and identification of three new tetrahydroxanthene-1,3(2H)-diones, uvarialeptones A-C, two new oxidized hexadiene derivatives, uvarialeptols A and B, together with ten known compounds. Their structures were elucidated by spectroscopic techniques and mass spectrometry. Uvarialeptones A and B were unprecedented tetrahydroxanthene-1,3(2H)-dione dimers which exhibited a cyclobutane ring via [2 + 2] cycloaddition from uvarialeptone C and 9a-O-methyloxymitrone, respectively. The structure of uvarialeptone A was confirmed by X-ray diffraction analysis using Mo Kα radiation. Compound 3 inhibited NO production at an IC50 value of 6.7 ± 0.1 μM.

Three new phenols and one new lignan from Clematis terniflora var. manshurica (Rupr.) Ohwi with their anti-inflammatory activity

Three undescribed phenols, mandshusica C-E (1–3) and a new lignan, mandshusica F (5), along with six known compounds (4, 6–10) were isolated from the roots and rhizomes of Clematis terniflora var. manshurica (Rupr.) Ohwi. Their structures were elucidated by extensive spectroscopic analysis as well as NMR and ECD calculations. Moreover, the possible biosynthetic pathways of compounds 1–3 were also discussed. All compounds were evaluated for their anti-inflammatory activities in LPS-induced RAW 264.7 cells. Compounds 1, 3, 4 significantly reduced the levels of NO and TNF-α, while compounds 2 and 8 significantly inhibited NO production in LPS-induced RAW264.7 cells.

“Bang Chang”, Thai Cultivar Chili Pepper (Capsicum annuum var. acuminatum) Extract in Rice Bran Oil and its Biological Activities

The Thai cultivar Capsicum, namely “Bang Chang chili pepper” (C. annuum var. acuminatum), is originally planted in Samut Songkhram, Thailand. Rice bran oil (RBO) is a healthy oil for preventing cardiovascular diseases. The study aimed to extract this chili pepper using RBO maceration, which was deemed safer. Capsicum extract was determined for capsaicin and β-carotene contents as bioactives of Capsicum and γ-oryzanol and γ-tocopherol as bioactives of RBO. Total phenolic content (TPC) was also monitored. The extract was further evaluated for in vitro biological activities, including antioxidant, anti-inflammatory, anti-obesity and anti-diabetic properties. Capsaicin contained in the extract was 0.002±0.0 mg/100 g non-pungent (0-700 SHU). Therefore, β-carotene was 3,489.5±15.2 μg/100 g, higher than dried chili pepper. γ-oryzanol and α-tocopherol contained in the extract were 4,939.6±11.0 mg/kg and 20,090±45.3 μg/100 g, which may affect its biological activities. However, TPC was a low amount (1.05±0.05 mg GAE/g). Capsicum extract moderately scavenged DPPH radicals (IC50 = 72.46±8.8 mg/mL) and preferred anti-inflammatory activity by inhibiting albumin degradation (IC50 = 1.09±0.04 mg/mL) and inhibiting NO production from macrophage cells (21.31±4.26%, at 0.1 mg/mL). Capsicum extract exerted in vitro anti-diabetic activity by inhibiting α-amylase and α-glucosidase (IC50 = 1.35±0.26 and greater than 1,000 mg/mL), while there was a lack of anti-lipase. Capsicum extract (0.0001-1.0 mg/mL) was non-toxic against human fibroblast cells. In conclusion, the simple extraction of this Capsicum within RBO contained bioactive compounds with non-pungency and exhibited biological properties for health benefits with non-toxicity that can be applied for external medicinal use and food seasoning.

Synthesis and anti-inflammatory activity of mogrol derivatives modified at C24 site

Mogrol, the aglycone of well-known sweeter mogrosides, shows potent anti-inflammatory activity. In this study, forty-two mogrol derivatives bearing various pharmacophores with oxygen or nitrogen atoms were designed and synthesized via structural modification at C24 site, and their anti-inflammatory activity were screened against lipopolysaccharide (LPS)-induced RAW264.7 cells. Compared with mogrol, most of derivatives exhibited stronger inhibition of NO production without cytotoxicity. In particular, compound B5 that contained an indole motif effectively suppressed the secretion of inflammatory mediators including TNF-α and IL-6, and inhibited the expression levels of TLR4, p-p65 and iNOS proteins. Molecular docking showed that the active B5 interacted with amino acid residues of iNOS protein through π-π stacking and hydrophobic interactions with binding affinity value of −12.1 kcal/mol, which was much stronger than mogrol (−8.9 kcal/mol). These results suggest that derivative B5 is a promising anti-inflammatory molecule and the strategy of hybridizing indole skeleton on mogrol is worthy for further attention.

Jiegeng decoction ameliorated acute pharyngitis through suppressing NF-κB and MAPK signaling pathways

Ethnopharmacological relevanceJiegeng decoction (JGD), consisting of Glycyrrhizae Radix et Rhizoma and Platycodonis Radix at the ratio of 2:1, is a classical Chinese medicine prescription firstly recorded in “Treatise on Febrile Diseases”. JGD has been extensively utilized to treat sore throat and lung diseases for thousands of years in China. However, the pharmacological effect and mechanism of JGD on acute pharyngitis (AP) remain unclear. Aim of the studyOur research aimed to reveal the pharmacological effect of JGD on AP and its potential mechanisms. Materials and methodsThe chemical components of JGD were analyzed based on the UPLC-MS analysis. The anti-inflammatory effect of JGD was evaluated by NO production using the Griess assay in RAW 264.7 cells. The mRNA expression of iNOS, IL-1β, IL-10, TNF-α, IL-6 and MCP-1 was determined by qRT-PCR in vitro. A 15% ammonia-induced AP model was established. The histopathology, the inflammatory cytokines IL-6 and MCP-1 in serum and the apoptosis-related genes caspease-8 and caspease-3 were determined by H&E staining, ELISA and qRT-PCR, respectively. The expression levels of p-p65, p65, p-JNK, JNK, p-p38, p38, p-ERK1/2, ERK1/2, and COX2 were measured through western blotting. ResultsNine compounds, including liquiritin, liquiritin apiosde, liquiritigenin, platycodin D, platycoside A, licorice saponin J2, licorice saponin G2, glycyrrhizic acid, and licochalcone A, were identified. JGD significantly inhibited NO production and regulated the mRNA expression levels of cytokines in LPS-stimulated RAW 264.7 cells. The results of in vivo experiments confirmed that JGD ameliorated AP through improving the pathological state of pharyngeal tissue, decreasing the serum levels of IL-6 and MCP-1 and preventing the tissue mRNA expression of caspease-8 and caspease-3. Furthermore, JGD also inhibited the NF-κB and MAPK pathways in the AP model. ConclusionsThis study suggested that JGD could alleviate AP through its anti-inflammation via NF-κB and MAPK pathways, which supported the traditional application of JGD for the treatment of throat diseases.

Taking advantage of the interaction between the sulfoxide and heme cofactor to develop indoleamine 2, 3-dioxygenase 1 inhibitors

Taking advantage of key interactions between sulfoxide and heme cofactor, we used the sulfoxide as the anchor functional group to develop two series of indoleamine 2, 3-dioxygenase 1 (IDO1) inhibitors: 2-benzylsulfinylbenzoxazoles (series 1) and 2-phenylsulfinylbenzoxazoles (series 2). In vitro enzymatic screening shows that both series can inhibit the activity of IDO1 in low micromolar (series 1) or nanomolar (series 2) levels. They also show inhibitory selectivity between IDO1 and tryptophan 2, 3-dioxygenase 2. Interestingly, although series 1 is less potent IDO1 inhibitors of these two series, it exhibited stronger inhibitory activity toward kynurenine production in interferon-γ stimulated BxPC-3 cells. Enzyme kinetics and binding studies demonstrated that 2-sulfinylbenzoxazoles are non-competitive inhibitors of tryptophan, and they interact with the ferrous form of heme. These results demonstrated 2-sulfinylbenzoxazoles as type II IDO1 inhibitors. Furthermore, molecular docking studies supports the sulfoxide being of the key functional group that interacts with the heme cofactor. Compound 22 (series 1) can inhibit NO production in a concentration dependent manner in lipopolysaccharides (LPS) stimulated RAW264.7 cells, and can relieve pulmonary edema and lung injury in LPS induced mouse acute lung injury models.

LC-MS/MS profiling of Tipuana tipu flower, HPLC-DAD quantification of its bioactive components, and interrelationships with antioxidant, and anti-inflammatory activity: in vitro and in silico approaches

BackgroundFabaceae plays a crucial role in African traditional medicine as a source of large number of important folk medication, agriculture and food plants. In a search of potential antioxidant and anti-inflammatory candidates derived from locally cultivated plants, the flowers of Tipuana tipu (Benth.) Lillo growing in Egypt were subjected to extensive biological and phytochemical studies. The impact of the extraction technique on the estimated biological activities was investigated.MethodsThe flowers were extracted using different solvents (aqueous, methanol, water/methanol (1:1), methanol/methylene chloride (1:1), and methylene chloride). The different extracts were subjected to antioxidant (DPPH, ABTS, and FRAP) and anti-inflammatory (COX-2 and 5-LOX) assays. The methanol extract was assessed for its inhibitory activity against iNOS, NO production, and pro-inflammatory cytokines (NF-KB, TNF-R2, TNF-α, IL-1β, and IL-6) in LPS-activated RAW 264.7 macrophages. The composition-activity relationship of the active methanol extract was further investigated using a comprehensive LC–QTOF-MS/MS analysis. The major identified phenolic compounds were further quantified using HPLC-DAD technique. The affinity of representative compounds to iNOS, COX-2, and 5-LOX target active sites was investigated using molecular docking and molecular dynamics simulations.ResultsThe methanol extract exhibited the highest radical scavenging capacity and enzyme inhibitory activities against COX-2 and 5-LOX enzymes with IC50 values of 10.6 ± 0.4 and 14.4 ± 1.0 µg/mL, respectively. It also inhibited iNOS enzyme activity, suppressed NO production, and decreased the secretion of pro-inflammatory cytokines. In total, 62 compounds were identified in the extract including flavonoids, coumarins, organic, phenolic, and fatty acids. Among them 18 phenolic compounds were quantified by HPLC-DAD. The highest docking scores were achieved by kaempferol-3-glucoside and orientin. Additionally, molecular dynamics simulations supported the docking findings.ConclusionThe flower could be considered a potentially valuable component in herbal medicines owing to its unique composition and promising bioactivities. These findings encourage increased propagation of T. tipu or even tissue culturing of its flowers for bioprospecting of novel anti-inflammatory drugs. Such applications could be adopted as future approaches that benefit the biomedical field.

A Characterization of Biological Activities and Bioactive Phenolics from the Non-Volatile Fraction of the Edible and Medicinal Halophyte Sea Fennel (Crithmum maritimum L.).

Although the biochemical composition and biological properties of the volatile fraction of the halophyte sea fennel (Crithmum maritimum L.) have been largely described, little is known about its polar constituents and bioactivities. Here, a hydromethanolic extract of Crithmum maritimum (L.) leaves was fractionated, and the fractions were evaluated in vitro for antioxidant (using DPPH, ABTS, and FRAP bioassays), anti-inflammatory (inhibition of NO production in RAW 264.7 macrophages), antidiabetic (alpha-glucosidase inhibition), neuroprotective (inhibition of acetylcholinesterase), and skin-protective (tyrosinase and melanogenesis inhibitions) activities. Polar fractions of the extract were rich in phenolics and, correlatively, displayed a strong antioxidant power. Moreover, fractions eluted with MeOH20 and MeOH80 exhibited a marked inhibition of alpha-glucosidase (IC50 = 0.02 and 0.04 mg/mL, respectively), MeOH60 fractions showed a strong capacity to reduce NO production in macrophages (IC50 = 6.4 μg/mL), and MeOH80 and MeOH100 fractions had strong anti-tyrosinase activities (630 mgKAE/gDW). NMR analyses revealed the predominance of chlorogenic acid in MeOH20 fractions, 3,5-dicaffeoylquinic acid in MeOH40 fractions, and 3-O-rutinoside, 3-O-glucoside, 3-O-galactoside, and 3-O-robinobioside derivatives of quercetin in MeOH60 fractions. These compounds likely account for the strong antidiabetic, antioxidant, and anti-inflammatory properties of sea-fennel polar extract, respectively. Overall, our results make sea fennel a valuable source of medicinal or nutraceutical agents to prevent diabetes, inflammation processes, and oxidative damage.

New eremophilane-type sesquiterpenes from Synotis solidaginea

Eleven new highly oxygenated eremophilane-type sesquiterpenoids were isolated from the whole plant of Synotis solidaginea, including two pairs of C-8 S/R epimers. The structures of the new compounds were elucidated on the basis of detailed spectroscopic analysis and the absolute configurations of 1 and 9 were confirmed by single-crystal X-ray crystallography using Cu Kα radiation. All the isolates were tested for the inhibition of LPS-stimulated NO production in macrophage-like mouse monocytic leukemia RAW264.7 cells. Compound 1 exhibited weak inhibitory effects with an IC50 of 71.2 μM.

Effects of Extraction Methods on the Physicochemical Properties and Biological Activities of heteroglycans from Hibiscus sabdariffa calyx

The hot-water extraction method has been employed to enhance the diffusion rate of heteroglycans, thereby augmenting the extraction efficiency. This study investigates the antioxidant activities and immunological properties of water-soluble polysaccharides derived from the Hibiscus sabdariffa calyx (HWPF and LWPF). These polysaccharides were isolated through two distinct extraction methods involving hot water followed by ethanol precipitation. The physicochemical characterization was conducted through a series of experiments encompassing monosaccharide composition, ultraviolet-visible spectrum analysis, and Fourier-transform infrared (FT-IR) spectroscopy. The evaluation of antioxidative properties employed various techniques, including DPPH and ABTS radical scavenging activities, Ferric Reducing Antioxidant Power, ferrous chelating power, total reducing power, and protection against DNA damage. The assessment of anti-inflammatory potential involved the inhibition of hemolytic activity induced by a hypotonic solution and heat. Furthermore, the impact of the polysaccharides on the production of pro-inflammatory cytokines was analyzed through Luminex assay and RTPCR assay in PBMCs and LPS-stimulated RAW 264.7 cells, respectively. The findings revealed that heteroglycans (LWPF and HWPF) exhibit a content of Ara-Man-Rha-GluA-GalA (41.2:17.2:15.7:9.2:8.8) and Ara-Glu-Rha-Xyl-GluA-Man (31.5:23.8:12.16:10.4:7:6) with molecular weights of approximately 4.5 KDa and 41.3 KDa, respectively. HWPF demonstrated robust metal chelating and scavenging activities. Additionally, each fraction exhibited substantial protection of DNA against damage induced by H2O2. LWPF was observed to significantly down-regulate the expression of pro-inflammatory cytokines IL-6 and COX-2 at both transcriptional and translational levels, along with inhibiting NO production. In summary, these results indicate that the choice of extraction methods influences both the structure and biological activities of heteroglycans, providing valuable insights into the structure-activity relationship.
 Keywords: Hibiscus sabdariffa, heteroglycans, hot water extraction, physicochemical properties, Antioxidant activity, Pro-inflammatory cytokines.

1H NMR guided isolation of 3-arylisoquinoline alkaloids from Hypecoum erectum L. and their anti-inflammation activity

Nine 3-arylisoquinoline alkaloids including five undescribed ones, hypectumines A-E (1–5), were isolated from the whole herb of Hypecoum erectum L. with the guidance of 1H-NMR. Their structures were established by a combination of 1D, 2D NMR, and HRESIMS spectrometry. Among them, hypectumines A and B possessed rare urea moieties while hypectumines C and D were characterized by 3-(methylamino)propanoic acid scaffolds. Biological assay demonstrated that alkaloids hypectumine B and 2,3-dimethoxy-N-formylcorydamine had anti-inflammatory effects by inhibiting NO production on LPS-induced RAW264.7 cells with IC50 values of 24.4 and 44.2 μM, respectively. Furthermore, hypectumine B could reduce the expression of pro-inflammatory cytokines TNF-α and IL-6, suggesting it might be a potential candidate for treating inflammatory disease.

Anti-Inflammatory Salicin Derivatives from the Barks of Salix tetrasperma.

The genus Salix L. is traditionally used in folk medicine to alleviate pain caused by various kinds of inflammation. In the present study, 10 undescribed salicin derivatives along with 5 known congeners were isolated from the barks of Salix tetrasperma, and their structures were elucidated by spectroscopic analyses, single-crystal X-ray diffraction, electronic circular dichroism (ECD) calculations, and chemical conversions. Compounds 4-6 significantly inhibited NO production in lipopolysaccharide (LPS)-induced RAW 264.7 macrophages, and the most active 4 obviously suppressed the production of IL-1β and IL-6 and decreased iNOS and COX-2 expression in a dose-dependent manner. Further Western blotting analysis revealed that the anti-inflammatory mechanism of 4 is possibly mediated through the MAPK and NF-κB signaling pathways.