Anti-inflammatory Effect of Methyl Gallate on Experimental Arthritis: Inhibition of Neutrophil Recruitment, Production of Inflammatory Mediators, and Activation of Macrophages

Co-administration of Ayurvedic medicines Arshogrit and Jatyadi Ghrit, attenuate croton oil-induced hemorrhoids in rat model of recto-anal inflammation by modulating TNF-α and IL-1β levels

OBJECTIVE

To study the efficacy of co-administration of Arshogrit (AG) and Jatyadi Ghrit (JG), two herb-based Ayurvedic medicines, in rat model of croton oil-induced hemorrhoids.

SIGNIFICANCE

Hemorrhoids refer to a pathological condition affecting the recto-anal region causing pain, swelling, bleeding and protrusion. The available therapies for hemorrhoids are symptomatic or invasive but are expensive and associated with adverse effects. Hence, there exists a need for efficacious and safer pharmacotherapies.

METHODS

Ultra high performance liquid chromatography detected nine phytocompounds in AG and seven in JG. Seven fatty acids were additionally identified in JG by Gas Chromatography-Mass Spectrometry analysis. The in-vivo efficacy of the co-administration of AG, which was administered orally at the doses of 20, 60 and 200 mg/kg/day and JG, which was topically applied (100 mg/animal/day) was evaluated in Wistar rats by inducing hemorrhoids development with the application of croton oil preparation (COP) in the recto-anal area. Prednisolone was employed as the standard drug and was administered orally at the dose of 1 mg/kg/day.

RESULTS

AG and JG were able to attenuate the croton oil-induced macro and microscopic anomalies. Gross pathological observation demonstrated remarkable decrease in croton oil-induced swelling, hemorrhage and formation of pseudomembrane, with the escalating doses of AG. Microscopic observation revealed alleviation in the histopathological lesions (necrosis, inflammation, hemorrhage/congestion, degeneration and dilatation of blood vessels). AG and JG additionally reduced COP-induced increase in the serum levels of pro-inflammatory cytokines.

CONCLUSION

This study convincingly demonstrates that co-administration of AG and JG is a potential therapy against hemorrhoids, warranting further investigations.

Biochemical and biological studies of irradiated and non-irradiated extracts of Solanum aculeastrum Dunal fruit

This study explores the impact of γ-irradiation on ethanolic extracts of Solanum aculeastrum Dunal. The anti-cancer and antimicrobial properties were investigated. The obtained results revealed that total phenol (TP) and total flavonoid (TF) of total ethanol extract (100%) (FTE) were higher than 70% ethanol extract (SE), and these contents increased after gamma radiation with 5 kGy. The results of minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the Solanum aculeastrum extracts suggested that FTE and 5 kGy-irradiated FTE can be used to control and prevent skin infections caused by MRSA and endocarditis, urinary tract infections, and prostatitis caused by Enterococcus faecalis. The FTE sample irradiated at 5 kGy showed cytotoxicity for A431 and Hct-116 cell lines similar to the control sample and higher than the toxicity revealed by the samples irradiated at 10 kGy. In normal cells (Bj-1), the toxicity was decreased after irradiation (IC50 = 31 μg/ml) compared to the non-irradiated extract (IC50 = 26.1 μg/ml). Molecular docking suggested Sortase A to play a role in chlorogenic acid antibacterial activity towards Staphylococcus aureus. In conclusion, γ-irradiation can be used to enhance the phytoconstituents of Solanum aculeastrum fruit extracts and, consequently, its biological properties.

Phytochemical screening, antibacterial, antioxidant, and cytotoxic activities of Geranium pusillum leaves

Traditional medicinal plants play an important role in primary health care worldwide. The phytochemical screening and activities of Geranium pusillum were investigated in this research. The dried plant leaves were extracted with ethanol, n-hexane, chloroform, dichloromethane, methanol, acetone, and aqueous solvents. These extracts were qualitatively analyzed, GC-MS, antimicrobial activities by using the disc diffusion method, antioxidant activity was determined by 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) radical scavenging, and cytotoxic activity was analyzed by the hemolytic activity of human red blood cells. The results showed phytochemicals such as flavonoids, terpenoids, steroids, phenols, saponins, tannins, and cardiac glycosides were detected in plant leaves. The ethanol extract at a concentration of 10 mg/mL showed a maximum inhibition zone 17.5 ± 0.09, 15.6 ± 0.11, 14.2 ± 0.17, 18.4 ± 0.11, 16.6 ± 0.15, 12.5 ± 0.13, 15.9 ± 0.10, and 13.1 ± 0.11 mm, and at 15 mg/mL showed 24.5 ± 0.09, 27.2 ± 0.12, 26.3 ± 0.17, 28.4 ± 0.10, 27.9 ± 0.16, 22.5 ± 0.13, 27.1 ± 0.10, and 24.1 ± 0.16 mm against Escherichia coli, Pasturella multocida (gram-negative), Staphylococcus aureus, Bacillus subtilus (gram-positive), Rhizopus solani, Aspergillus flavus, Aspergillus niger, and Alternaria alternate (fungal strain), respectively, and dichloromethane showed a minimum inhibition zone as compared to other extracts against bacterial as well as fungal strains. Chloroform extract had maximum antioxidant activity (45.00 ± 0.08%) and minimum in dichloromethane (12.20 ± 0.04%). Cytotoxic activity was found maximum in acetone extract (19.83 ± 0.07%) and minimum in ethanol extract (4.72 ± 0.04%). It is concluded that phytochemicals like phenols, flavonoids, and others may be responsible for these activities, which is why this plant is used for traditional medicine. RESEARCH HIGHLIGHTS: Geranium pusillum has therapeutic properties that exhibit various biological activities beneficial for human health. G. pusillum has significant inhibitory effects against bacterial and fungal strains. Chloroform solvent extract indicates potential free radical scavenging abilities. Acetone extract exhibits notable effects on human red blood cells and demonstrates significant cytotoxic activity.

Methyl gallate: Review of pharmacological activity

Methyl gallate (MG) is a polyphenolic compound widely found in natural plants. MG has been shown to have a variety of biological functions, including anti-tumor, anti-inflammatory, anti-oxidant, neuroprotective, hepatoprotective and anti-microbial activities, and has broad research and development prospects. A total of 88 articles related to MG were searched using the PubMed, Science Direct, and Google Scholar databases, systematically investigating the pharmacological activity and molecular mechanisms of MG. There were no restrictions on the publication years, and the last search was conducted on June 5, 2023. MG can exert pharmacological effects through multiple pathways and targets, such as PI3K/Akt, ERK1/2, Caspase, AMPK/NF-κB, Wnt/β-catenin, TLR4/NF-κB, MAPK, p53, NLRP3, ROS, EMT. According to the literature, MG has the potential to be a prospective adjuvant for anticancer therapy and deserves further study.

Lipoxygenase inhibitory synthetic derivatives of methyl gallate regulate gene expressions of COX-2 and cytokines to reduce animal model arthritis

Mammalian lipoxygenases (LOXs) are involved in the biosynthesis of mediators of anaphylactic reactions and have been implicated in cell maturation, the pathogenesis of bronchial asthma, atherosclerosis, rheumatoid arthritis, cardiovascular diseases, Alzheimer's disease and osteoporosis. Hence LOX inhibition in chronic conditions can lead to reducing the disease progression, which can be a good target for treating these diseases. The present study deals with designing methyl gallate derivatives and their anti-inflammatory effect by in silico, in vitro and in vivo methods. Designed derivatives were docked against LOX enzyme, and molecular dynamic simulations were carried out. Following the synthesis of derivatives, in vitro LOX inhibition assay, enzyme kinetics and fluorescence quenching studies were performed. One of the derivatives of methyl gallate (MGSD 1) was demonstrated as an anti-inflammatory agent for the treatment of rheumatoid arthritis in the animal model. Amelioration of Freund's complete adjuvant (FCA)-induced arthritis by methyl gallate and its derivative with a concentration of 10-40 mg.kg-1 has been assessed in vivo in a 28-day-long study. TNF-α and COX-2 gene expression were also studied. Methyl gallate synthetic derivatives (MGSDs) inhibited LOX with an IC50 of 100 nM, 304 nM, and 226 nM for MGSD 1, MGSD 2, and MGSD 3, respectively. Fluorescence quenching methods also prove their binding characteristics, and 200 ns simulations studies showed that the RMSDs for the entire complex were less than 2.8 Å. The in vivo results showed that methyl gallate was required approximately five times diclofenac for the same level of effect, and the synthesised (MGSD 1) compound required only approximately 1/12 of diclofenac for the same level of effect in in-vivo studies. The preeminent expression of COX-2 and TNF-α genes was significantly decreased after the treatment of the methyl gallate derivative. Hence, the in vivo results showed that the referenced synthetic derivative might have more arthritis-reducing properties than the parent compound methyl gallate and is more potent than the standard drug diclofenac, with no apparent induced toxicity.

Methyl gallate nanomicelles impairs neutrophil accumulated in zymosan-induced arthritis

Arthritis is a chronic disease that affects, approximately, 1 % of the total global population. It is characterized by chronic inflammation, accompanied in most of the cases of motor disability and sever pain. The main therapies available have high risk of failure and advanced treatments are scarce and highly cost. In this scenario, search for effective, safe and low-cost treatments is quite desirable. Methyl gallate (MG) is a plant-derived phenolic compound described to present remarkable anti-inflammatory effect in experimental models of arthritis. Thus, in this study we formulated nanomicelles of MG using Pluronic (F-127) as matrix and evaluated in vivo the pharmacokinetic, biodistribution and its effect in the mice model of zymosan-induced arthritis. The nanomicelles were formed with a size 126 nm. The biodistribution showed a ubiquitous tissue deposition with a renal excretion. The pharmacokinetics showed elimination half-life of 1.72 h and a clearance of 0.006 L/h. The oral pretreatment with nanomicelles containing MG (3.5 or 7 mg/kg) demonstrated a reduction in total leukocytes, neutrophils, and mononuclear cells from the inflammation site. The data supports the use of methyl gallate nanomicelles as an alternative drug for arthritis. DATA AVAILABILITY: All the data of this study are transparent.

Effects of Leea indica leaf extracts and its phytoconstituents on natural killer cell-mediated cytotoxicity in human ovarian cancer

BACKGROUND

The rich biodiversity of medicinal plants and their importance as sources of novel therapeutics and lead compounds warrant further research. Despite advances in debulking surgery and chemotherapy, the risks of recurrence of ovarian cancer and resistance to therapy are significant and the clinical outcomes of ovarian cancer remain poor or even incurable.

OBJECTIVE

This study aims to investigate the effects of leaf extracts from a medicinal plant Leea indica and its selected phytoconstituents on human ovarian cancer cells and in combination with oxaliplatin and natural killer (NK) cells.

METHODS

Fresh, healthy leaves of L. indica were harvested and extracted in 70% methanol by maceration. The crude extract was partitioned with n-hexane, dichloromethane and ethyl acetate. Selected extracts and compounds were analyzed for their effects on cell viability of human ovarian cancer cells, NK cell cytotoxicity, and stress ligands expression for NK cell receptors. They were also evaluated for their effects on TNF-α and IL-1β production by enzyme-linked immunosorbent assay in lipopolysaccharide-stimulated human U937 macrophages.

RESULTS

Leaf extracts of L. indica increased the susceptibility of human ovarian tumor cells to NK cell-mediated cytotoxicity. Treatment of cancer cells with methyl gallate but not gallic acid upregulated the expression of stress ligands. Tumor cells pretreated with combination of methyl gallate and low concentration of oxaliplatin displayed increased levels of stress ligands expression and concomitantly enhanced susceptibility to NK cell-mediated cytolysis. Further, NK cells completely abrogated the growth of methyl gallate-pretreated ovarian cancer cells. The leaf extracts suppressed TNF-α and IL-1β production in human U937 macrophages. Methyl gallate was more potent than gallic acid in down-regulating these cytokine levels.

CONCLUSIONS

We demonstrated for the first time that leaf extracts of L. indica and its phytoconstituent methyl gallate enhanced the susceptibility of ovarian tumor cells to NK cell cytolysis. These results suggest that the combined effect of methyl gallate, oxaliplatin and NK cells in ovarian cancer cells warrants further investigation, for example for refractory ovarian cancer. Our work is a step towards better scientific understanding of the traditional anticancer use of L. indica.

Chemical composition and effects of ethanolic extract and gel of Cochlospermum regium (Schrank) Pilg. Leaves on inflammation, pain, and wounds

ETHNOPHARMACOLOGICAL RELEVANCE

Cochlospermum regium is well-known as "Algodãozinho do cerrado" in folk Brazilian medicine, and is used to fight infections, inflammation and skin disorders.

AIM OF THE STUDY

To identify the phytochemical constituents and the effects of the ethanolic extract of C. regium leaves (EECR) on inflammation and pain, and the effects of C. regium gel (GEECR) on wound healing.

MATERIALS AND METHODS

Animals were treated with EECR (30-300 mg/kg) or GEECR (1.25 and 2.5%) and studies were conducted using carrageenan-induced pleurisy and paw edema tests, formalin-induced pain model, and excision wound model.

RESULTS

In total, 25 compounds, including quercitrin, methyl gallate, and 1,2,3,4,6-pentagalloylhexose, with highest detectability were identified. The treatments reduced leukocyte migration, nitric oxide production, protein extravasation, edema, mechanical hyperalgesia, pain in both phases (neurogenic and inflammatory), cold hypersensitivity, and improved wound closure and tissue regeneration.

CONCLUSIONS

The present findings established the anti-inflammatory, anti-nociceptive, and wound healing potential of the leaves of C. regium, confirming the potential therapeutic effect of this plant.

Development and Application of Whole-Cell Biosensors for the Detection of Gallic Acid

Gallic acid is a prevalent secondary plant metabolite distinguished as one of the most effective free-radical scavengers among phenolic acids. This compound is also known for its cytotoxic, anti-inflammatory, and antimicrobial activities. Bulk quantities of gallic acid are conventionally produced by acid hydrolysis of tannins, a costly and environmentally hazardous process. With the aim to develop more sustainable approaches, microbial bioproduction strategies have been attempted recently. To advance synthetic biology and metabolic engineering of microorganisms for gallic acid production, we characterize here a transcription factor-based inducible system PpGalR/P_{PP_RS13150} that responds to the extracellular gallic acid in a dose-dependent manner in Pseudomonas putida KT2440. Surprisingly, this compound does not mediate induction when PpGalR/P_{PP_RS13150} is used in non-native host background. We show that the activation of the inducible system requires gallate dioxygenase activity encoded by galA gene. The 4-oxalomesaconic acid, an intermediate of gallic acid-metabolism, is identified as the effector molecule that interacts with the transcription factor GalR mediating activation of gene expression. Introduction of galA gene along galR enables development of biosensors suitable for detection and monitoring of gallic acid extracellularly using non-native hosts such as E. coli and C. necator. Moreover, the P. putida-based biosensor's applicability is demonstrated by detecting and measuring gallic acid in extracts of Camellia sinensis leaves. This study reports the strategy, which can be applied for developing gallic acid biosensors using bacterial species outside Pseudomonas genus.

Effect of the main constituents of Pistacia lentiscus leaves against the DPPH radical and xanthine oxidase: experimental and theoretical study

The aim of this work is to study the content of phenolic compounds in P lentiscus leaves and their antioxidant effect. After extracting the phenolic compounds, fractionation by liquid/liquid partition with increasing polarity gives five extracts. Three of them (ButF, AqF and ButA) were found to have good antioxidant activity. Their IC_50s for the inhibition of the free radical formation of DPPH are 1.76 µg/mL, 1.307 µg/ml, and 1.77 µg/mL, respectively. These values are very interesting, considering the effect of the powerful flavonoid quercetin, whose IC₅₀ against DPPH is 1.53 µg/mL. These extracts are also active against xanthine oxidase (XO). The IC_50s measured are 0.14 mg/mL, 0.186 mg/mL and 0.33 mg/mL for ButF, Aq F and ButAq F extract respectively, in comparison with allopurinol (0.44 mg/mL). A phytochemical analysis by LC/ESI-MS-MS was performed to explain the observed activities. The results show 22 peaks representing: flavanols, namely catechin, d-Gallocatechin, and gallocatechin gallate. The only flavone detected in the studied extracts was luteolin glucuronide and was found to be in higher amounts in butanolic extract (2,71mg/mL). The phenolic acids and derivatives were also identified in the extracts. A theoretical study was performed to deduce the specificity of the binding between the major compounds identified in the P. lentiscus extract and the xanthine oxidase enzyme using Schrödinger software. The docking procedure was validated using the extraction of ligands from the binding site. Their re-anchoring to the xanthine oxidase structure using quercetin and allopurinol was considered reference molecules. After docking, post-docking minimization was performed to achieve the best scoring poses with the MM-GBSA approach. The dGBind energy of MM-GBSA representing the binding energy of the receptor and the ligand was calculated based on molecular mechanics. Results reveal that β-Glucogallin compounds such as Digalloylquinic acid, Gallocatechin, and Myricetin-3-O rhamnoside are more active than allopurinol, with stronger Docking score (Gscore) and MM-GBSA dGBind.Communicated by Ramaswamy H. Sarma.

Phenethyl Ester of Gallic Acid Ameliorates Experimental Autoimmune Encephalomyelitis

Gallic acid is a phenolic acid present in various plants, nuts, and fruits. It is well known for its anti-oxidative and anti-inflammatory properties. The phenethyl ester of gallic acid (PEGA) was synthesized with the aim of increasing the bioavailability of gallic acid, and thus its pharmacological potential. Here, the effects of PEGA on encephalitogenic cells were examined, and PEGA was found to modulate the inflammatory activities of T cells and macrophages/microglia. Specifically, PEGA reduced the release of interleukin (IL)-17 and interferon (IFN)-γ from T cells, as well as NO, and IL-6 from macrophages/microglia. Importantly, PEGA ameliorated experimental autoimmune encephalomyelitis, an animal model of chronic inflammatory disease of the central nervous system (CNS)-multiple sclerosis. Thus, PEGA is a potent anti-inflammatory compound with a perspective to be further explored in the context of CNS autoimmunity and other chronic inflammatory disorders.

Herbo-mineral formulation, Divya-Swasari-Vati averts SARS-CoV-2 pseudovirus entry into human alveolar epithelial cells by interfering with spike protein-ACE 2 interaction and IL-6/TNF-α /NF-κB signaling

The herbo-mineral formulation, Divya-Swasari-Vati (DSV), is a well-known Ayurvedic medication for respiratory ailments. In a recent pre-clinical study, DSV rescued humanized zebrafish from SARS-CoV-2 S-protein-induced pathologies. This merited for an independent evaluation of DSV as a SARS-CoV-2 entry inhibitor in the human host cell and its effectiveness in ameliorating associated cytokine production. The ELISA-based protein-protein interaction study showed that DSV inhibited the interactions of recombinant human ACE 2 with three different variants of S proteins, namely, Smut 1 (the first reported variant), Smut 2 (W436R variant) and Smut 3 (D614G variant). Entry of recombinant vesicular stomatitis SARS-CoV-2 (VSVppSARS-2S) pseudovirus, having firefly luciferase and EGFP reporters, was assessed through luciferase assay and fluorescent microscopy. DSV exhibited dose-dependent inhibition of VSVppSARS-2S pseudovirus entry into human lung epithelial A549 cells and also suppressed elevated levels of secreted pro-inflammatory cytokines such as interleukin-6 (IL-6), interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) induced by viral infection mimicking Poly I:C-, S-protein- and VSVppSARS-2S pseudovirus. In human immune cells, DSV also moderated TNF-α-mediated NF-κB induction, in a dose-dependent manner. The observed anti-viral effect of DSV against SARS-CoV-2 is attributable to the presence of different metabolites Summarily, the observations from this study biochemically demonstrated that DSV interfered with the interaction between SARS-CoV-2 S-protein and human ACE 2 receptor which consequently, inhibited viral entry into the host cells and concomitant induction of inflammatory response.

Phragmanthera austroarabica A.G.Mill. and J.A.Nyberg Triggers Apoptosis in MDA-MB-231 Cells In Vitro and In Vivo Assays: Simultaneous Determination of Selected Constituents

Phragmanthera austroarabica (Loranthaceae), a semi-parasitic plant, is well known for its high content of polyphenols that are responsible for its antioxidant and anti-inflammatory activities. Gallic acid, catechin, and methyl gallate are bioactive metabolites of common occurrence in the family of Loranthaceae. Herein, the concentrations of these bioactive metabolites were assessed using high-performance thin layer chromatography (HPTLC). Methyl gallate, catechin, and gallic acid were scanned at 280 nm. Their concentrations were assessed as 14.5, 6.5 and 43.6 mg/g of plant dry extract, respectively. Phragmanthera austroarabica extract as well as the three pure compounds were evaluated regarding the cytotoxic activity. The plant extract exhibited promising cytotoxic activity against MDA-MB-231 breast cells with the IC₅₀ value of 19.8 μg/mL while the tested pure compounds displayed IC₅₀ values in the range of 21.26–29.6 μg/mL. For apoptosis investigation, P. austroarabica induced apoptotic cell death by 111-fold change and necrosis by 9.31-fold change. It also activated the proapoptotic genes markers and inhibited the antiapoptotic gene, validating the apoptosis mechanism. Moreover, in vivo studies revealed a significant reduction in the breast tumor volume and weight in solid Ehrlich carcinoma (SEC) mice. The treatment of SEC mice with P. austroarabica extract improved both hematological and biochemical parameters with amelioration in the liver and kidney histopathology to near normal. Taken together, P. austroarabica extract exhibited promising anti-cancer activity through an apoptosis-induction.

Inflammation Modulating Activity of the Hydroethanol Stem Bark Extract of Bombax costatum in Murine Models

Bombax costatum (Bombacaceae) is traditionally used as a decoction of the leaves, stem, and root to treat headaches, fever, and oedema that may be associated with inflammatory conditions. Thus, the aim of this study was to evaluate the effect of 70%^v/_v ethanolic extract of the stem bark of Bombax costatum on acute and chronic inflammation. The effect of Bombax costatum extract (10, 50, 100 mg kg^-1, p.o) was studied in prostaglandin E₂-induced paw oedema in Sprague-Dawley rats (n = 5). Subsequently, the effect of the extract on clonidine and haloperidol-induced catalepsy was also investigated in ICR mice (n = 5). Finally, the ability of the extract to inhibit chronic inflammation was studied using a rat adjuvant-induced arthritis model. Pre-emptive and therapeutic administration of the extract at all doses significantly suppressed the formation of oedema following prostaglandin E ₂ administration. As a measure of indirect antihistaminic effect, treatment with the extract suppressed clonidine-induced catalepsy but not haloperidol-induced catalepsy. Moreover, Bombax costatum extract significantly inhibited joint inflammation and damage following injection of complete Freund's adjuvant. Treatment with the extract also inhibited the onset of polyarthritis; thus, suppressing the systemic spread of joint inflammation from ipsilateral limbs to contralateral limbs. In conclusion, the hydroethanol extract of the stem bark of Bombax costatum inhibits both acute and chronic inflammation.

New dimer and trimer of chalcone derivatives from anti-inflammatory and antinociceptive extracts of Schinopsis brasiliensis roots

ETHNOPHARMACOLOGY RELEVANCE

Schinopsis brasiliensis Engl. is an endemic tree of the Brazilian semi-arid regions belonging to the Anacardiaceae family. It is the main representative of the genus Schinopsis, mostly native to Brazil and popularly known as "braúna" or "baraúna". Different parts of this plant are employed in Brazilian folk medicines to treat inflammation in general, sexual impotence, cough, and influenza.

AIM OF THE STUDY

This work describes the antinociceptive (acetic acid-induced writhing and formalin-induced nociception) and anti-inflammatory (paw edema and neutrophil migration) activities of the extract of the root of S. brasiliensis. Besides, the evaluation of total phenolic compounds and antioxidant, antimicrobial (including MRSA bacteria), and acetylcholinesterase inhibition activities were also determined.

MATERIAL AND METHODS

The pure compounds were isolated by different chromatographic techniques and their chemical structures have been unambiguously elucidated based on extensive spectroscopic methods, including 1D (¹H, ¹³C, DEPT, and NOEdiff) and 2D (HSQC, HMBC, and NOESY) NMR experiments, MS data, and comparison with the literature data of similar compounds. The antinociceptive and anti-inflammatory activities were evaluated by acid acetic writhing test, formalin paw edema, and by the investigation of neutrophil migration to the peritoneal cavities of mice. For antimicrobial evaluation were determined MIC and MBC, antioxidant activities were obtained by TPC and DPPH tests, and AChE inhibition by Elmann's methodology.

RESULTS

The extracts showed antinociceptive and anti-inflammatory activities and two unusual new compounds, a cyclobutanyl chalcone trimer (schinopsone A) and a cyclohexene-containing chalcone dimer (schinopsone B), with six known compounds were isolated from the active extracts. Additionally, the acetylcholinesterase inhibitory activity for isolated compounds was reported for the first time in this study. Molecular docking studies indicated that the isolated compounds are responsible for the interaction with anti-inflammatory targets (COX 1 and 2 and LOX) with variable binding affinities, indicating a possible mechanism of action of these compounds.

CONCLUSIONS

These findings indicate for the first time the correlation between the anti-inflammatory activity different enriched polyphenol-organic soluble fractions of S. brasiliensis, and it contributes to the understanding of the anti-inflammatory potential of S. brasiliensis.

The Isopropyl Gallate Counteracts Cyclophosphamide-Induced Hemorrhagic Cystitis in Mice

Hemorrhagic cystitis is the main adverse effect associated with the clinical use of oxazaphosphorine, resulting in increased oxidative stress and proinflammatory cytokines, which culminate in injury of the bladder tissue. The aim of this study was to evaluate the protective effect of isopropyl gallate (IPG) against ifosfamide (IFOS)-induced hemorrhagic cystitis in mice. The induction of the hemorrhagic cystitis model was carried out using a single dose of IFOS (400 mg/kg, i.p.) four hours after oral pretreatment with IPG (6.25, 12.5, 25, and 50 mg/kg) or saline (vehicle). Mesna (positive control; 80 mg/kg, i.p.) was administered four hours before and eight hours after induction of cystitis. In the present study, IPG 25 mg/kg significantly decreased edema and hemorrhage, with a reduction of the bladder wet weight (36.86%), hemoglobin content (54.55%), and peritoneal vascular permeability (42.94%) in urinary bladders of mice. Interestingly, IPG increased SOD activity (89.27%) and reduced MDA levels (35.53%), as well as displayed anti-inflammatory activity by decreasing TNF-α (88.77%), IL-1β (62.87%), and C-reactive protein (56.41%) levels. Our findings demonstrate that IPG has a substantial protective role against IFOS-induced hemorrhagic cystitis in mice by enhancing antioxidant activity and proinflammatory mechanisms. Thus, IPG represents a promising co-adjuvant agent in oxazaphosphorine-based chemotherapy treatments.

Protective effect of methyl gallate on murine antigen-induced arthritis by inhibiting inflammatory process and bone erosion

Methyl gallate (MG) is a plant-derived phenolic compound known to present remarkable anti-inflammatory effect in different experimental models, such as paw oedema, pleurisy, zymosan-induced arthritis and colitis. Herein we investigated the effect of MG in the mice model of antigen-induced arthritis (AIA), a model with complex inflammatory response, driven primally by immune process and that cause bone and cartilage erosion similarly found in rheumatoid arthritis. Arthritis was induced by intra-articular injection of albumin methylated from bovine serum (mBSA) in C57BL/6 male mice previously immunized. The dose-response analysis of MG (0.7-70 mg/kg; p.o) showed that maximum inhibition was reached with the dose of 7 mg/kg on paw oedema and cell infiltration induced by AIA at 7 h. Treatment with MG (7 mg/kg; p.o) or with the positive control, dexamethasone (Dexa, 10 mg/kg, ip) reduced AIA oedema formation, leukocyte infiltration, release of extracellular DNA and cytokine production 7 and 24 h (acute response). Mice treated daily with MG for 7 days showed no significant weight loss or liver and kidney toxicity contrary to dexamethasone that induced some degree of toxicity. Prolonged treatment with MG inhibited the late inflammatory response (28 days) reducing oedema formation, cell infiltration, synovial hyperplasia, pannus formation and cartilage degradation as observed in histopathological analyses. Ultimately, MG reduced bone resorption as evidenced by a decrease in tartrate-resistant acid phosphate (TRAP)-positive cells number in femur histology. Altogether, we demonstrate that MG ameliorates the inflammatory reaction driven primarily by the immune process, suggesting a potential therapeutic application in arthritis treatment.

Methyl Gallate Improves Hyperuricemia Nephropathy Mice Through Inhibiting NLRP3 Pathway

Hyperuricemia nephropathy (HN) is a form of chronic tubulointerstitial inflammation, caused by the deposition of monosodium urate crystals (MSU) in the distal collecting duct and medullary interstitium, associated with a secondary inflammatory reaction. Numerous published reports indicated that NLRP3 inflammasome pathway play crucial roles in HN symptoms. The present study aims to investigate the protective effects of methyl gallate on HN mice and the underlying mechanisms. An HN model was established by intraperitoneal injection of potassium oxide (PO) to assess the effect of methyl gallate on renal histopathological changes, renal function, cytokine levels and expressions of NLRP3-related protein in HN mice. Moreover, in vitro models of lipopolysaccharide (LPS)-stimulated bone marrow-derived macrophages (BMDMs) and human peripheral blood mononuclear cells (PBMCs) were established to explore the mechanism of methyl gallate on NLRP3 inflammasome activation. The results showed that methyl gallate significantly ameliorated HN by inhibiting uric acid production and promoting uric acid excretion as well as ameliorating renal injury induced by NLRP3 activation. Mechanistically, methyl gallate is a direct NLRP3 inhibitor that inhibits NLRP3 inflammasome activation but has no effect on the activation of AIM2 or NLRC4 inflammasomes in macrophages. Furthermore, methyl gallate inhibited the assembly of NLRP3 inflammasomes by blocking the ROS over-generation and oligomerization of NLRP3. Methyl gallate was also active ex vivo against ATP-treated PBMCs and synovial fluid mononuclear cells from patients with gout. In conclusion, methyl gallate has a nephroprotective effect against PO-induced HN through blocking the oligomerization of NLRP3 and then exerting anti-inflammatory activity in the NLRP3-driven diseases.

Nanoparticle conjugated with aptamer anti-MUC1/Y for inflammatory arthritis

Aptamers may form well-defined three-dimensional structures binding with high affinity and stability to a specific receptor. The aptamer anti-MUC1 isoform Y is one the most used due the affinity to MUC1, which is overexpressed in several types of cancer and inflammation process. In this study we have developed, characterized, in vitro as in vivo evaluated a nanoaptamer (anti-MUC1/Y) as a nanoagent for rheumatoid arthritis treatment. The results showed that a nanoaptamer with a size range of 241 nm was produced. The entrapment efficacy was 90% with a biodistribution showing a high hepatic uptake (>98%). The results in vivo showed a potent effect in arthritis experimental model, especially in low doses. The results corroborate the applicability of this nanosystem for RA treatment.

Intra-articular use of radium dichloride ([223Ra] RaCl2) showed relevant anti-inflammatory response on experimental arthritis model

Rheumatoid arthritis (RA) is an inflammatory chronic autoimmune disease. The treatment of RA is difficult and, in many cases, ineffective, and the arsenal of drugs is limited. Due the longevity of the disease, RA may cause extreme musculoskeletal disorders with a high impact on quality of life. Also, RA is related with severe comorbidities decreasing the life expectancy. Finally, RA has been reported to impact in economy and healthy public. In this direction, the necessity to discover new strategies to efficiently treat RA is immediate. In this direction, we have reported the use of low doses of [223Ra] RaCl2 (radium dichloride) as intra-articular injection to treat RA. Mice were post-treated with [223Ra] RaCl2 (1.48 µCi; i.a.) 24 h after zymosan stimulus. Zymosan-induced arthrithis is responsible for leucocyte recruitment (total leukocytes, neutrophils, and mononuclear cells), which were inhibited by intra-articular injection of [223Ra] RaCl2 (69%, 77%, and 66%, respectively).

Gallincin ameliorates colitis-associated inflammation and barrier function in mice based on network pharmacology prediction

Objective

To explore potential mechanisms and effects of gallincin on a mouse model of colitis induced by dextran sulfate sodium (DSS).

Methods

Network pharmacology analysis was used to predict the molecular mechanism of action of gallincin for treatment of colitis. Gallincin was administered orally to mice with DSS-induced colitis. Expression of tumor necrosis factor α (TNF-α), D-lactate, and interleukin-1β (IL-1β) and myeloperoxidase activity were assessed with real-time quantitative PCR and an enzyme-linked immunoassay, respectively. Expression of occludin, zonula occludens 1 (ZO-1), and phosphorylated extracellular signal-regulated protein kinase1/2 (p-ERK1/2) was analyzed with immunohistochemical staining and/or western blot assays.

Results

Using a network pharmacology approach, 12 mapping targets between gallincin and colitis were obtained, including ERK/mitogen-activated protein kinase. Further investigations in an experimental colitis mouse model showed that gallincin significantly ameliorated experimental colitis, reduced D-lactate levels, and remarkably increased occludin and ZO-1 expression, possibly in part by decreasing IL-1β, TNF-α, and p-ERK1/2 levels and inhibiting leukocyte penetration.

Conclusions

Gallincin regulated colonic barrier function and reduced colitis-associated inflammation, suggesting it is a promising drug for the treatment of ulcerative colitis.

In vitro antibacterial activity of Loxostylis alata extracts and isolated compounds against Salmonella species

Background

Owing to antibiotic resistance, alternative antimicrobials from medicinal plants are receiving attention as leads for anti-infective agents. This study aimed to investigate selected tree species and their constituents for activity against bacterial foodborne pathogens, particularly Salmonella serovars.

Methods

Antibacterial activity of ten plant species was determined by serial microdilution against bacteria implicated in causing gastrointestinal ailments. Active compounds were isolated from Loxostylis alata using bioassay-guided fractionation. Antioxidant activity was determined using free-radical scavenging assays. Cytotoxicity and genotoxicity of the extracts was ascertained on Vero cells, and using the Ames assay respectively.

Results

Extracts had low to moderate MIC values from 0.04 to 2.5 mg/mL. Protorhus longifolia and Loxostylis alata were most active and L. alata had the highest selectivity index value (2.51) against Salmonella Typhimurium, as well as high antioxidant activity. Cytotoxicity values ranged from 0.02 to 0.47 mg/mL, while tested extracts were not genotoxic. Bioactive compounds isolated from L. alata included delicaflavone and a polymethoxyflavone.

Conclusions

The Loxostylis alata leaf extract had strong activity against Salmonella serovars but isolated compounds were less active, indicating likely synergistic effects. Extracts of L. alata are promising candidates for development of antimicrobial preparations or food additives against microbial contamination.

Local administration of p-coumaric acid decreases lipopolysaccharide-induced acute lung injury in mice: In vitro and in silico studies

Acute lung injury (ALI) remains to cause a high rate of mortality in critically ill patients. It is known that inflammation is a key factor in the pathogenesis of lipopolysaccharide (LPS)-induced ALI, which makes it a relevant approach to the treatment of ALI. In this study, we evaluated the potential of nasally instilled p-coumaric acid to prevent LPS-induced ALI in mice, by evaluating its effects on cellular and molecular targets involved in inflammatory response via in vitro and in silico approaches. Our results demonstrated that p-coumaric acid reduced both neutrophil accumulation and pro-inflammatory cytokine abundance, and simultaneously increased IL-10 production at the site of inflammation, potentially contributing to protection against LPS-induced ALI in mice. In the in vitro experiments, we observed inhibitory effects of p-coumaric acid against IL-6 and IL-8 production in stimulated A549 cells, as well as reactive oxygen species generation by neutrophils. In addition, p-coumaric acid treatment decreased neutrophil adhesion on the TNF-α-stimulated endothelial cells. According to the in silico predictions, p-coumaric acid reached stable interactions with both the ATP-binding site of IKKβ as well as the regions within LFA-1, critical for interaction with ICAM-1, thereby suppressing the production of proinflammatory mediators and hindering the neutrophil infiltration, respectively. Collectively, these findings indicate that p-coumaric acid is a promising anti-inflammatory agent that can be used for developing a pharmaceutical drug for the treatment of ALI and other inflammatory disorders.

Calcio-Herbal Medicine Divya-Swasari-Vati Ameliorates SARS-CoV-2 Spike Protein-Induced Pathological Features and Inflammation in Humanized Zebrafish Model by Moderating IL-6 and TNF-α Cytokines

PURPOSE

Severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) infection has grown into a pandemic and without a specific cure, disease management is the need of the hour through symptomatic interventions. Studies with severe acute respiratory syndrome-coronavirus (SARS-CoV) have highlighted the role of herbal medicines either in combination with antiviral drugs or by themselves in curtailing the severity of infection and associated inflammation. Divya-Swasari-Vati is an Indian ayurvedic formulation used in the treatment of chronic cough and lung inflammation, which is one of the first symptoms of SARS-CoV-2 infections.

METHODS

In this study, we used a A549 cell xenotransplant in the swim bladder of zebrafish and modeled the SARS-CoV-2 infection by injecting the fish with a recombinant spike protein. The different groups were given normal feed or feed mixed with either dexamethasone (as the control drug) or Divya-Swasari-Vati. The changes in behavioral fever, infiltration of pro-inflammatory cells in the swim bladder, degeneration or presence of necrotic cells in the kidney, and gene expression of pro-inflammatory cytokines were studied to determine the rescue of the diseased phenotype.

RESULTS

Challenge with the spike protein caused changes in the swim bladder cytology with infiltrating pro-inflammatory cells, skin hemorrhage, and increase in behavioral fever. This was also accompanied by increased mortality of the disease control fish. Treatment with Divya-Swasari-Vati reversed most of the disease symptoms including damage to the kidney glomerulocytes, and complete reversal of behavioral fever. Dexamethasone, used as a comparator, was only able to partly rescue the behavioral fever phenotype. Divya-Swasari-Vati also suppressed the pro-inflammatory cytokines, IL-6 and TNF-α, levels in a dose-dependent manner, under in vivo and in vitro conditions.

CONCLUSION

The study showed that the A549 xenotransplanted zebrafish injected with the recombinant spike protein of SARS-CoV-2 is an efficient model for the disease; and treatment with Divya-Swasari-Vati medicine rescued most of the inflammatory damage caused by the viral spike protein while increasing survival of the experimental fish.

Bilberry (Vaccinium myrtillus L.) Extracts Comparative Analysis Regarding Their Phytonutrient Profiles, Antioxidant Capacity along with the In Vivo Rescue Effects Tested on a Drosophila melanogaster High-Sugar Diet Model

Bilberries (Vaccinium myrtillus L.) have been reported to hold a plentitude of health-promoting properties beyond basic nutrition, mainly attributed to their anthocyanin content and antioxidant activity. In this article, we built the phytochemical profile of three wild bilberry fruit extract formulations (aqueous, methanolic, and hydro-methanolic) using UHPLC-ESI-MS/MS putative analysis, identifying 88 individual phytochemicals, mainly flavonoids (total content 8.41 ± 0.11 mg QE/g dw), free amino acids, polyphenols (total content 21.68 ± 0.19 mg GAE/g dw), carboxylic acids, and vitamins. Furthermore, the antioxidant activity of the extract was assessed, reaching 78.03 ± 0.16% DPPH free radical scavenging activity, comparable to literature values determined for bilberry extracts of other origin. Due to the increased prevalence of metabolic syndrome and based on the reviewed benefits of bilberries, we tested the most potent formulation of our bilberry extracts in this biological context. The in vivo rescue effect of a bilberry extract supplemented diet on Drosophila melanogaster was assessed by monitoring biochemical and genomic markers. Hemolymph trehalose levels were halved upon addition of 3% hydro-methanolic bilberry extract to a high-sugar (1.5 M sucrose) diet, as compared to the non-supplemented high-sugar diet. Noteworthy, the rescue seen for flies kept on the bilberry extract supplemented high-sugar diet appeared to parallel the trehalose levels observed in the case of the control diet (50 mM sucrose) flies. Moreover, next to the trehalose-lowering type of in vivo effects, other gene expression related rescues were also detected for genes such as InR, Akh, AstA, AstC, Irk, Npc2g, and CCHa2 upon supplementation of the high-sugar diet with our hydro-methanolic bilberry fruit extract. Our findings suggest that such a bilberry fruit extract could generate physiological and genomic type of compensatory mechanisms so that further translational approaches would advance the understanding of some human specific pathological conditions.

Bioactive components, antioxidant and antimicrobial activities of Paeonia rockii fruit during development

In last ten years, much attention focused on tree peony fruit (TPF) for edible oil production despite other potential utilization. The present study identified and quantified 29 bioactive components by liquid chromatography-electrospray ionization-triple quadrupole-mass spectrometry (LC-ESI-QqQ-MS) targeted approach during the development of TPF. Trans-resveratrol, benzoic acid, luteolin, and methyl gallate were selected as predominant chemical markers between seeds and pods through principal component analysis (PCA) and orthogonal partial least square-discriminant analysis (OPLS-DA). Extremely high levels of paeoniflorin (1893 mg/100 g) and trans-resveratrol (1793 mg/100 g) were observed at stage 2 (S2) and S6 in seeds, respectively. Antioxidant activities determined by ABTS^+•, DPPH^•, and FRAP assays showed significant correlations with total phenolic content (TPC) and total flavonoid content (TFC). The strongest antibacterial effects of pod and seed against Staphylococcus aureus and Proteus vulgaris occurred at initial stages and maturation stages. TPF could be a potential source of bioactive compounds with functional properties.

Methyl gallate attenuates inflammation induced by Toll-like receptor ligands by inhibiting MAPK and NF-Κb signaling pathways

OBJECTIVE AND DESIGN

Methyl gallate (MG) is a prevalent polyphenol in the plant kingdom, which may be related to the effects of several medicinal plants. Although it is widely reported that polyphenols have therapeutic effects, there are few studies demonstrating that MG has anti-inflammatory action. This study aimed to investigate the molecular mechanism behind the anti-inflammatory activity of MG and its effect on hyperalgesia.

METHODS

Swiss mice were pretreated orally with different doses of MG and subjected to i.pl. injection of zymosan to induce paw edema. RAW264.7 macrophages and BMDMs stimulated with different TLR agonists such as zymosan, LPS, or Pam3CSK₄ were used to investigate the molecular mechanisms of MG RESULTS: MG inhibits zymosan-induced paw edema and hyperalgesia and modulates molecular pathways crucial for inflammation development. Pretreatment with MG inhibited cytokines production and NF-κB activity by RAW 264.7 cells stimulated with zymosan, Pam3CSK₄ or LPS, but not with PMA. Moreover, pretreatment with MG decreased IκB degradation, nuclear translocation of NF-κBp65, c-jun and c-fos and ERK1/2, p38 and JNK phosphorylation.

CONCLUSION

Thus, the results of this study demonstrate that MG has a promising anti-inflammatory effect and suggests an explanation of its mechanism of action through the inhibition of NF-κB signaling and the MAPK pathway.

Medicinal plants used against various inflammatory biomarkers for the management of rheumatoid arthritis

OBJECTIVES

Rheumatoid arthritis is a chronic autoimmune disease manifested clinically by polyarthralgia associated with joint dysfunction triggering the antibodies targeting against the self-neoepitopes determined by autoimmune responses associated with chronic arthritic attacks. The activation of macrophages and other defence cells in response to self-epitopes as biomarkers in RA provides a better understanding of pathogenesis of disease and has led to the development of novel therapeutic approaches acting as potent inhibitors of these cells.

KEY FINDINGS

The current review retrieved the various medicinal plants possessing an active phytoconstituents with anti-inflammatory and antioxidant properties, which tends to be effective alternative approach over the synthetic drugs concerned with high toxic effects. The current available literature provided an evident data concluding that the active constituents like fatty acids, flavonoids, terpenes and sesquiterpene lactones attenuate the RA symptoms by targeting the inflammatory biomarkers involved in the pathogenesis of RA.

SUMMARY

Despite the various synthetic treatment approaches targeting immune cells, cytokines improved the quality of life but still the drug management is challenging due to toxic and chronic teratogenic effects with anti-arthritic drugs. The current review has elaborated the selected traditionally used herbal medicinal plants with phytoconstituents possessing anti-inflammatory activity by suppressing the inflammatory biomarkers with lesser side effects and providing the future exploration of natural drug therapy for rheumatoid arthritis.

Anti-Inflammatory Principles from Tamarix aphylla L.: A Bioassay-Guided Fractionation Study

Natural products have served as primary remedies since ancient times due to their cultural acceptance and outstanding biodiversity. To investigate whether Tamarix aphylla L. modulates an inflammatory process, we carried out bioassay-guided isolation where the extracts and isolated compounds were tested for their modulatory effects on several inflammatory indicators, such as nitric oxide (NO), reactive oxygen species (ROS), proinflammatory cytokine; tumour necrosis factor (TNF-α), as well as the proliferation of the lymphocyte T-cells. The aqueous ethanolic extract of the plant inhibited the intracellular ROS production, NO generation, and T-cell proliferation. The aqueous ethanolic crude extract was partitioned by liquid-liquid fractionation using n-hexane (n-C₆H₆), dichloromethane (DCM), ethyl acetate (EtOAc), n-butanol (n-BuOH), and water (H₂O). The DCM and n-BuOH extracts showed the highest activity against most inflammatory indicators and were further purified to obtain compounds 1-4. The structures of 3,5-dihydroxy-4',7-dimethoxyflavone (1) and 3,5-dihydroxy-4-methoxybenzoic acid methyl ester (2) from the DCM extracts; and kaempferol (3), and 3-hydroxy-4-methoxy-(E)-cinnamic acid (4) from the n-BuOH extract were elucidated by different spectroscopic tools, including MS, NMR, UV, and IR. Compound 2 inhibited the production of ROS and TNF-α, whereas compound 3 showed inhibitory activity against all the tested mediators. A better understanding of the potential aspect of Tamarix aphylla L. derivatives as anti-inflammatory agents could open the door for the development of advanced anti-inflammatory entities.

Evaluation of the pharmacokinetic-pharmacodynamic integration of marbofloxacin in combination with methyl gallate against Salmonella Typhimurium in rats

Fluoroquinolone resistance in Salmonella Typhimurium is becoming a major concern. Hence, an intervention to limit the growth in resistance is inevitable. One way to combat this challenge is through combination therapy. The combination of antibiotics with phytochemicals has become an ideal means of preventing antimicrobial resistance. Recently, in an in vitro study, the combination of methyl gallate (MG) with marbofloxacin (MAR) has shown to prevent Salmonella Typhimurium invasion. It is also worth to study the effects of plant extracts on the pharmacokinetics of antibiotics. Hence, the objective of this study was to determine the effect of MG on the pharmacokinetics of MAR and pharmacokinetics/pharmacodynamics integration of MG and MAR. The micro-broth dilution method was used to obtain the minimum inhibitory concentration (MIC), and fractional inhibitory concentration (FIC) of MAR and MG. Whereas, the pharmacokinetic was conducted in rats by administering either MAR alone or combined with MG through oral and/or intravenous routes. The results indicated that the MIC of MAR and MG against standard strain Salmonella Typhimurium (ATCC 14028) was 0.031 and 500 μg/mL, respectively. The FIC_index of the combination of MAR and MG was 0.5. For orally administered drugs, the C_max and AUC_24h of MAR were 1.04 and 0.78 μg/mL and 5.98 and 6.11 h.μg/mL when MAR was given alone and in combination with MG, respectively. The intravenous administration of MAR showed a half-life of 3.8 and 3.9 h; a clearance rate of 1.1 and 0.73 L/h/kg and a volume of distribution of 5.98 and 4.13 L/kg for MAR alone and in combination with MG, respectively. The AUC₂₄/MIC for MAR alone and in combination with MG was 192.8 and 381.9 h, respectively. In conclusion, MG has shown to increase the antimicrobial activity of MAR in vitro and ex vivo experiments without affecting the pharmacokinetics of MAR in rats.

Anti-Inflammatory Derivatives with Dual Mechanism of Action from the Metabolomic Screening of Poincianella pluviosa

Metabolomics approaches have become fundamental strategies for the analysis of complex mixtures, guiding the isolation of target compounds by focusing on unpublished or promising pharmacological properties. The discovery of novel anti-inflammatory agents is important due to several limitations regarding their potency, efficacy, and adverse effects. Thus, novel anti-inflammatory candidates are essential, aiming to find agents with better mechanisms of action. In this context, extracts from Poincianella pluviosa var. peltophoroides demonstrated significant in vivo anti-inflammatory potential. Thus, metabolomics analysis based on UHPLC-UV-HRFTMS data was performed for the identification of biomarkers with anti-inflammatory properties. Metabolomics-guided chromatographic process led to the isolation of novel compounds 4‴-methoxycaesalpinioflavone and 7-methoxycaesalpinioflavone, as well as known derivatives rhuschalcone VI and caesalpinioflavone. Isolated compounds caused edema inhibition and neutrophil recruitment. Two of them showed better efficacy than reference drugs (indomethacin and dexamethasone). Results of in vivo experiments corroborated those obtained through metabolomics and statistical analyses guiding the isolation of substances of interest.

Antinociceptive compounds and LC-DAD-ESIMSn profile from Dictyoloma vandellianum leaves

Limonoids, quinolone alkaloids and chromones have been reported as constituents of Dictyoloma vandellianum Adr. Juss. (Rutaceae). Although those compounds are known for their biological activities, only the anti-inflammatory activity of chromones isolated from the underground parts has been evaluated. There are no studies of the pharmacological properties of the aerial parts of D. vandellianum. The present study was carried out to determine the phytochemical profile and antinociceptive activity of the methanol extract, fractions and isolated compounds of leaves of D. vandellianum. The phytochemical profile was performed by HLPC-DAD-ESIMSⁿ and pure substances obtained were characterized by MS and NMR spectroscopy. The antinociceptive activity was assessed using the formalin assay in mice, and the motor function in the rotarod test. ME and all the fractions obtained from ME produced antinociceptive effects. Among them, the ethyl ether fraction was the most active. Data from HPLC-DAD-ESIMSⁿ showed that the ethyl ether fraction presented 42 compounds. The major compounds isolated from this fraction—gallic acid, methyl gallate and 1,2,6-tri-O-galloyl-β-d-glucopyranose–were tested and produced antinociceptive effects. Gallic acid, methyl gallate and 1,2,6-tri-O-galloyl-β-d-glucopyranose at antinociceptive doses did not affect the motor performance in mice in the rotarod test. This work is the first report of the occurrence of gallotanins in D. vandellianum. In addition, the pharmacological study showed that D. vandellianum leaves present antinociceptive activity, probably induced by gallic acid, methyl gallate and 1,2,6-tri-O-galloyl-β-d-glucopyranose.

Green synthesis of methyl gallate conjugated silver nanoparticles: a colorimetric probe for gentamicin

A highly efficient colorimetric sensor for gentamicin is proposed based on methyl gallate conjugated silver nanoparticles.

Phenolic Compounds in Organic and Aqueous Extracts from Acacia farnesiana Pods Analyzed by ULPS-ESI-Q-oa/TOF-MS. In Vitro Antioxidant Activity and Anti-Inflammatory Response in CD-1 Mice

BACKGROUND

Acacia farnesiana (AF) pods have been traditionally used to treat dyspepsia, diarrhea and topically for dermal inflammation. Main objectives: (1) investigate the antioxidant activity and protection against oxidative-induced damage of six extracts from AF pods and (2) their capacity to curb the inflammation process as well as to down-regulate the pro-inflammatory mediators.

METHODS

Five organic extracts (chloroformic, hexanic, ketonic, methanolic, methanolic:aqueous and one aqueous extract) were obtained and analyzed by UPLC-ESI-Q-oa/TOF-MS. Antioxidant activity (DPPH•, ORAC and FRAP assays) and lipid peroxidation (TBARS assay) were performed. Assessment of anti-inflammatory properties was made by the ear edema induced model in CD-1 mice and MPO activity assay. Likewise, histological analysis, IL-1β, IL-6, IL-10, TNF-α, COX measurements plus nitrite and immunohistochemistry analysis were carried out.

RESULTS

Methyl gallate, gallic acid, galloyl glucose isomer 1, galloyl glucose isomer 2, galloyl glucose isomer 3, digalloyl glucose isomer 1, digalloyl glucose isomer 2, digalloyl glucose isomer 3, digalloyl glucose isomer 4, hydroxytyrosol acetate, quinic acid, and caffeoylmalic acid were identified. Both organic and aqueous extracts displayed antioxidant activity. All extracts exhibited a positive effect on the interleukins, COX and immunohistochemistry assays.

CONCLUSION

All AF pod extracts can be effective as antioxidant and topical anti-inflammatory agents.

Advances in extraction and analysis of phenolic compounds from plant materials

Phenolic compounds, the most abundant secondary metabolites in plants, have received more and more attention in recent years because of their distinct bioactivities. This review summarizes different types of phenolic compounds and their extraction and analytical methods used in the recent reports, involving 59 phenolic compounds from 52 kinds of plants. The extraction methods include solid-liquid extraction, ultrasound-assisted extractions, microwave-assisted extractions, supercritical fluid extraction, and other methods. The analysis methods include spectrophotometry, gas chromatography, liquid chromatography, thin-layer chromatography, capillary electrophoresis, and near-infrared spectroscopy. After illustrating the specific conditions of the analytical methods, the advantages and disadvantages of each method are also summarized, pointing out their respective suitability. This review provides valuable reference for identification and/or quantification of phenolic compounds from natural products.

Potential usefulness of methyl gallate in the treatment of experimental colitis

Methyl gallate is a gallotannin widely distributed in nature. Previous studies have demonstrated its antioxidant, anti-inflammatory, antimicrobial and anti-tumor activities. In the present study, the activity of methyl gallate on experimental models of inflammatory bowel disease has been investigated. Experimental colitis was induced in Sprague-Dawley rats through the intracolonic instillation of an acetic acid solution (2 mL, 4% v/v). Methyl gallate (100 and 300 mg/kg, p.o.) and the reference drug mesalazine (100 mg/kg, p.o.) were tested. Methyl gallate induced a significant reduction in the colon weight/length ratio and macroscopic lesion score. Besides, the malondialdehyde content and the GSSG/GSH ratio were remarkably decreased. Furthermore, the administration of methyl gallate reduced the expression of COX₂, IL-6, TNFα and the severity of microscopic tissue damage induced by acetic acid, while the mean goblet cell density was significantly higher in both the group treated with methyl gallate and the one treated with mesalazine, in comparison with untreated animals. The Na⁺K⁺ATPase pump activity was recovered in treated groups (control: 827.2 ± 59.6, colitis: 311.6 ± 54.8, methyl gallate 100 mg/kg: 642.2 ± 175.0, methyl gallate 300 mg/kg: 809.7 ± 100.6, mesalazine: 525.3 ± 81.7). Methyl gallate was also found to induce a significant reduction in the castor oil-induced intestinal motility in Swiss mice, decreasing the peristalsis by 74.5 and 58.82% at 100 and 300 mg/kg p.o., respectively. This compound also antagonized the jejunum contractions induced by Ach and CaCl₂. This study demonstrates that methyl gallate exerts beneficial effects in a preclinical model of intestinal disorders.

The flavonoid quercetin inhibits titanium dioxide (TiO2)-induced chronic arthritis in mice

Titanium dioxide (TiO₂) is a common component of orthopedic prosthesis. However, prosthesis wear releases TiO₂, which induces inflammation and osteolysis in peri-prosthetic tissues. Quercetin is a flavonoid widely present in human diet, which presents biological activities such as antinociceptive, anti-inflammatory and antioxidant effects. Therefore, the effect of intraperitoneal treatment with quercetin in TiO₂-induced arthritis model was evaluated. In the first set of experiments, mice received injection of TiO₂ (0.1-3 mg/knee joint) and articular mechanical hyperalgesia, edema and histopathology analysis were performed in a 30 days protocol. The dose of 3 mg of TiO₂ showed the most harmful effect, and was chosen to the following experiments. Subsequently, mice received 3 mg of TiO₂ followed by post-treatment with quercetin during 30 days. Quercetin (10-100 mg/kg) inhibited in a dose-dependent manner TiO₂-induced knee joint mechanical hyperalgesia, edema and leukocyte recruitment and did not induce damage in major organs such as liver, kidney and stomach. The dose of 30 mg/kg was chosen for the subsequent analysis, and reduced histopathological changes such as leukocyte infiltration, vascular proliferation and synovial hyperplasia (pannus formation) on day 30 after TiO₂ challenge. The protective analgesic and anti-inflammatory mechanisms of quercetin included the inhibition of TiO₂-induced neutrophil and macrophage recruitment, proteoglycan degradation, oxidative stress, cytokine production (TNF-α, IL-1β, IL-6, and IL-10), COX-2 mRNA expression, and bone resorption as well as activation of Nrf2/HO-1 signaling pathway. These results demonstrate the potential therapeutic applicability of the dietary flavonoid quercetin to reduce pain and inflammatory damages associated with prosthesis wear process-induced arthritis.

Chemical composition and diuretic, natriuretic and kaliuretic effects of extracts of Mimosa bimucronata (DC.) Kuntze leaves and its majority constituent methyl gallate in rats

Objectives

Some species of the genus Mimosa showed promising results in previous investigations, which include diuretic effect; however, no chemical analyses or animal model has been conducted so far to evaluate the biological properties of M. bimucronata.

Methods

Male Wistar rats received the oral treatment with vehicle; hydrochlorothiazide; methanolic extract from M. bimucronata (MEMB), dichloromethane (DCM) and ethyl acetate (EA) fractions or methyl gallate (MG). The cumulative urine volume, electrolytes excretion, pH and osmolality were determined at the end of the experiment.

Key findings

The chemical studies demonstrated that the phenolic compounds are the majorities in the plant, with the MG being the main substance identified. We showed that MEMB and EA fraction, but not DCM, exhibited diuretic and saluretic effects. Similarly, the MG also revealed diuretic, natriuretic and kaliuretic properties to both normotensive and spontaneously hypertensive rats. Atropine, a muscarinic receptor antagonist, fully prevented MG-induced diuresis and saluresis. In addition, MG did not alter the viability of A7r5 and L929 cell lines and neither stimulated nitric oxide generation.

Conclusions

These findings suggest that M. bimucronata extracts and its majority compound MG present diuretic, natriuretic and kaliuretic properties, which was dependent on the activation of muscarinic acetylcholine receptor.

Wnt/β-catenin signaling plays a distinct role in methyl gallate-mediated inhibition of adipogenesis

The canonical Wnt/β-catenin signaling not only features in many developmental processes but also recently emerged as an attractive negative regulator of differentiation of preadipocytes into adipocytes. Here, we show that β-catenin signaling plays a distinct role in methyl gallate (MG)-mediated inhibition of 3T3-L1 adipocytes differentiation. We found that the expression of β-catenin decreased after adipogenic hormonal induction, whereas incubation of the differentiating cells with a physiological concentration of MG during adipogenic hormonal induction significantly prevented β-catenin degradation by activating Wnt signaling components such as Wnt1, Wnt10b, Fzd1, Fzd2, Lrp5, Lrp6, Dvl1, and Dvl2. Mechanistic experiments revealed that MG treatment during early adipocytic differentiation specifically inhibited degradation of β-catenin caused by phosphorylation at serine-33. In addition, MG treatment led to phosphorylation of GSK3β, which is one of β-catenin-degrading enzymes. Consequently, MG treatment facilitated translocation of the stabilized β-catenin from the cytoplasm to nucleus, and activates its target genes cyclin D1 and c-Myc. Furthermore, MG-induced stabilization of β-catenin suppresses PPARγ expression. Moreover, pharmacological activation or inhibition of β-catenin signaling during adipocytes differentiation decreased and increased, respectively, the level of the key adipogenic marker, PPARγ, and of its downstream targets, aP2 and adiponectin while MG treatment effectively reversed their expression level. Collectively, our data suggest that MG is a novel pharmacological stimulator of canonical Wnt/β-catenin signaling, and therefore represents a promising therapeutic agent in obesity.