Structure-activity relationship for antiinflammatory effect of luteolin and its derived glycosides

Luteolin for neurodegenerative diseases: a review

Neurodegenerative diseases such as Parkinson's disease, Alzheimer's disease, Huntington's disease, and multiple sclerosis affect millions of people around the world. In addition to age, which is a key factor contributing to the development of all neurodegenerative diseases, genetic and environmental components are also important risk factors. Current methods of treating neurodegenerative diseases are mostly symptomatic and do not eliminate the cause of the disease. Many studies focus on searching for natural substances with neuroprotective properties that could be used as an adjuvant therapy in the inhibition of the neurodegeneration process. These compounds include flavonoids, such as luteolin, showing significant anti-inflammatory, antioxidant, and neuroprotective activity. Increasing evidence suggests that luteolin may confer protection against neurodegeneration. In this review, we summarize the scientific reports from preclinical in vitro and in vivo studies regarding the beneficial effects of luteolin in neurodegenerative diseases. Luteolin was studied most extensively in various models of Alzheimer's disease but there are also several reports showing its neuroprotective effects in models of Parkinson's disease. Though very limited, studies on possible protective effects of luteolin against Huntington's disease and multiple sclerosis are also discussed here. Overall, although preclinical studies show the potential benefits of luteolin in neurodegenerative disorders, clinical evidence on its therapeutic efficacy is still deficient.

Chemical profile, in vitro pharmacological activity and Satureja cuneifolia Ten. evaluation of essential oil based on distillation time

The medicinal plant Satureja cuneifolia Ten. was widely utilized as spice, tea and traditional medicine. The objective of the current study was to examine the chemical composition and in vitro biological activities (LOX, MMP-1, and MMP-12 enzyme inhibition activity and cytotoxicity on A549 cell line) of Satureja cuneifolia extracts and essential oils. The essential oils of the flowering aerial parts were hydro-distilled at four different distillation times (5, 30, 60, and 180 min) using the Clevenger apparatus. The total essential oil and four fragments were compared in terms of the major component, yield, and distillation time. Volatile compounds of the infusion were extracted by using HS-SPME. Ethanolic extract had the strongest inhibition activity on the LOX enzyme (84.50%), while the essential oils exhibited more cytotoxic activity on the A549 cell line than the extracts. The oils and the infusion were analyzed using GC-MS and the primary chemicals identified by LC-MS/MS.

Luteolin as a potential hepatoprotective drug: Molecular mechanisms and treatment strategies

Luteolin is a flavonoid widely present in various traditional Chinese medicines. In recent years, luteolin has received more attention due to its impressive liver protective effect, such as metabolic associated fatty liver disease, hepatic fibrosis and hepatoma. This article summarizes the pharmacological effects, pharmacokinetic characteristics, and toxicity of luteolin against liver diseases, and provides prospect. The results indicate that luteolin improves liver lesions through various mechanisms, including inhibiting inflammatory factors, reducing oxidative stress, regulating lipid balance, slowing down excessive aggregation of extracellular matrix, inducing apoptosis and autophagy of liver cancer cells. Pharmacokinetics research manifested that due to metabolic effects, the bioavailability of luteolin is relatively low. It is worth noting that appropriate modification, new delivery systems, and derivatives can enhance its bioavailability. Although many studies have shown that the toxicity of luteolin is minimal, strict toxicity experiments are still needed to evaluate its safety and promote its reasonable development. In addition, this study also discussed the clinical applications related to luteolin, indicating that it is a key component of commonly used liver protective drugs in clinical practice. In view of its excellent pharmacological effects, luteolin is expected to become a potential drug for the treatment of various liver diseases.

Effects and Mechanisms of Kaempferol in the Management of Cancers through Modulation of Inflammation and Signal Transduction Pathways

Cancer is the principal cause of death and its incidence is increasing continuously worldwide. Various treatment approaches are in practice to treat cancer, but these treatment strategies may be associated with severe side effects and also produce drug resistance. However, natural compounds have established their role in cancer management with minimal side effects. In this vista, kaempferol, a natural polyphenol, mainly found in vegetables and fruits, has been revealed to have many health-promoting effects. Besides its health-promoting potential, its anti-cancer potential has also been described in in vivo as well as in in vitro studies. The anti-cancer potential of kaempferol has been proven through modulation of cell signaling pathways in addition to the induction of apoptosis and cell cycle arrest in cancer cells. It leads to the activation of tumor suppressor genes, inhibition of angiogenesis, PI3K/AKT pathways, STAT3, transcription factor AP-1, Nrf2 and other cell signaling molecules. Poor bioavailability of this compound is one of the major limitations for its proper and effective disease management actions. Recently, some novel nanoparticle-based formulations have been used to overcome these limitations. The aim of this review is to provide a clear picture regarding the mechanism of action of kaempferol in different cancers through the modulation of cell signaling molecules. Besides this, strategies to improve the efficacy and synergistic effects of this compound have also been described. However, more studies are needed based on clinical trials to fully explore the therapeutic role of this compound, especially in cancer treatment.

Pharmacological activities and effective substances of the component-based Chinese medicine of Ginkgo biloba leaves based on serum pharmacochemistry, metabonomics and network pharmacology

As a potential drug candidate for the treatment of hypertension and complications, it is speculated that the component-based Chinese medicine of Ginkgo biloba leaves (GBCCM) which mainly composed of flavonoid aglycones (FAs) and terpene lactones (TLs) may have different pharmacological effects at different doses or ratios. Taking the normal mice as the study object, metabonomics was conducted by giving different doses of GBCCM. Based on the components of GBCCM absorbed into the blood, the network pharmacological prediction was carried out. By integrating the results of metabonomics and network pharmacology, predict the possible pharmacological effects of GBCCM and conduct experimental verification. It was found that eight of the 19 compounds in GBCCM could be absorbed into the blood. GBCCM mainly affected the signal pathways of unsaturated fatty acid, pyruvate, bile acid, melanin and stem cells. It was speculated that GBCCM might have activities such as lowering blood pressure, regulating stem cell proliferation and melanogenesis. By establishing the models of mushroom tyrosinase, rat bone marrow mesenchymal stem cells (BMSCs) and spontaneously hypertensive rats (SHRs), we found that FAs and TLs showed synergistic effect in hypertension and tyrosinase models, and the optimal ratio was 3:2 (4.4 mg/kg) and 1:1 (0.4 mg/ml), respectively. As effective substances, FAs significantly promoted the proliferation of rat BMSCs on the third and fifth days at the concentration of 0.2 μg/ml (p < 0.05). GBCCM showed a variety of pharmacological effects at different doses and ratios, which provided an important reference for the druggability of GBCCM.

Interactions between phenolic constituents of Scutellaria salviifolia and key targets associated with inflammation: network pharmacology, molecular docking analysis and in vitro assays

Scutellaria salviifolia Benth. (SS), an endemic plant for Turkey, is used for gastric ailments as folk medicine. In this study, we aimed to uncover the underlying molecular mechanisms with the help of network pharmacology and molecular docking analysis in the inflammation processes of gastric ailments. Gene enrichment analysis and target screening were carried out. Experimental validation was performed via cytokines of nitric oxide (NO) and interleukin-6 (IL-6) in LPS stimulated RAW 264.7 cells. Furthermore, antioxidant activity studies were performed by radical scavenging effects on different radicals. A total of 144 targets were listed for the isolated compounds where 26 of them were related to selected inflammation targets. According to the gene enrichment analysis, HIF1 signaling pathway and TNF signaling pathway were found to be involved in inflammation. We also defined AKT1, TNF, EGFR, and COX2 as key targets due to the protein-protein interactions of 26 common targets. The extract inhibited NO and IL-6 production at 100 and 200 µg/mL, while flavonoid-rich fraction possessed significant anti-inflammatory activity at the concentration of 50 and 100 µg/mL via NO and IL-6 production, respectively. It is thought that the anti-inflammatory effects of extracts, fractions and pure compounds were achieved by reducing NO and IL-6 levels via regulating the NF-κB pathway or reducing NO production by suppressing iNOS through the HIF-1 pathway when evaluated together with the results of network analysis and literature. Anti-inflammatory activities of the extract and fractions were promising and comparably with S. baicalensis, commonly used for its anti-inflammatory activity.

Natural sources, biological effects, and pharmacological properties of cynaroside

Cynaroside is a flavonoid, isolated from several species belonging to the Apiaceae, Poaceae, Lamiaceae, Solanaceae, Zingiberaceae, Compositae and other families and it can be extracted from seeds, roots, stems, leaves, barks, flowers, fruits, aerial parts, and the whole plant of these species. This paper discloses the current state of knowledge on the biological/pharmacological effects and mode of action to better understand the numerous health benefits of cynaroside. Several research works revealed that cynaroside could have beneficial effects on various human pathologies. Indeed, this flavonoid exerts antibacterial, antifungal, antileishmanial, antioxidant, hepatoprotective, antidiabetic, anti-inflammatory, and anticancer effects. Additionally, cynaroside exhibits its anticancer effects by blocking MET/AKT/mTOR axis by decreasing the phosphorylation level of AKT, mTOR, and P70S6K. For antibacterial activity, cynaroside reduces biofilm development of Pseudomonas aeruginosa and Staphylococcus aureus. Moreover, the incidence of mutations leading to ciprofloxacin resistance in Salmonella typhimurium was reduced after the treatment with cynaroside. In addition, cynaroside inhibited the production of reactive oxygen species (ROS), which reduced the damage to mitochondrial membrane potential caused by hydrogen peroxide (H₂O₂). It also enhanced the expression of the anti-apoptotic protein Bcl-2 and lowered that of the pro-apoptotic protein Bax. Cynaroside abrogated the up-regulation of c-Jun N-terminal kinase (JNK) and p53 protein expression triggered by H₂O₂. All these findings suggest that cynaroside could be used to prevent certain human diseases.

Biological Activities of the Fruit Essential Oil, Fruit, and Root Extracts of Ferula drudeana Korovin, the Putative Anatolian Ecotype of the Silphion Plant

In the present study, preliminary phytochemical investigations were performed on the fruit essential oil and antioxidant-rich methanolic extracts of the fruits and roots of Ferula drudeana, the putative Anatolian ecotype of the Silphion plant, to corroborate its medicinal plant potential and identify its unique characteristics amongst other Ferula species. The essential oil from the fruits of the endemic species Ferula drudeana collected from Aksaray was analyzed by GC and GC/MS. The main components of the oil were determined as shyobunone (44.2%) and 6-epishyobunone (12.6%). The essential oil of the fruits and various solvent extracts of the fruits and roots of F. drudeana were evaluated for their antibacterial and anticandidal activity using microbroth dilution methods. The essential oil of the fruits, methanol, and methylene chloride extracts of the fruits and roots showed weak to moderate inhibitory activity against all tested microorganisms with MIC values of 78-2000 µg/mL. However, the petroleum ether extract of the roots showed remarkable inhibitory activity against Candida krusei and Candida utilis with MIC values of 19.5 and 9.75 µg/mL, respectively. Furthermore, all the samples were tested for their antioxidant activities using DPPH^• TLC spot testing, online HPLC-ABTS screening, and DPPH/ABTS radical scavenging activity assessment assays. Methanolic extracts of the fruits and roots showed strong antioxidant activity in both systems.

Semi-Synthesis of Flavonoid Glycosides and Their Anti-Inflammatory and Antitumor Activities towards Triple Negative Breast Cancer

BACKGROUND

Flavonoid glycosides are known to possess diverse bioactivities including antitumor and anti-inflammatory properties. Hesperetin is abundant in nature and can be used to synthesize bioactive flavonoids. This has the advantages of low cost, short synthetic steps, simple operation, and good yields.

OBJECTIVE

In this study, we aimed to synthesize bioactive flavonoids and flavonoid glycosides from hesperetin and evaluate the antitumor and anti-inflammatory activities of these compounds.

METHODS

A series of flavonoids and their derivatives were synthesized by methoxylation, oxidative dehydrogenation, benzylation, debenzylation, and deacetylation as well as using a modified peroxyacetone method and a glycoside condensation reaction. Their anti-inflammatory activities were evaluated for their inhibitory effects on nitric oxide (NO), tumor necrosis factor (TNF-α), and interleukin-6 (IL-6) production in LPS-induced RAW264.7 mouse macrophages. Their structures were characterized by HRMS, ¹ H-NMR, and ¹³ C-NMR, and their cytotoxicity on the human triple-negative breast cancer cell (TNBC) line, SUM 149, was tested by using the MST assay.

RESULTS

Most of the compounds markedly reduced NO production in LPS-stimulated murine macrophages at the tested concentrations in a dose-dependent manner. Among these, compounds 1, 7, 9, and 17 showed significant anti-inflammatory activities against NO production in LPS-induced RAW264.7 mouse macrophages. In addition, they could also reduce the release of TNF-α and IL-6 in a concentration-dependent manner. Most of the tested compounds showed remarkable anti-human TNBC activities. Compounds 1b-1m, 1, and 3 showed a certain degree of growth inhibition effect on the human TNBC cell lines and their IC₅₀ values were all below 16.61 μM. In addition, compound 1l was the most cytotoxic with IC₅₀ values of 1.38±0.31 μM, while the other compounds were inactive with inhibition rates <50 % at the highest concentration tested (20 μM).

CONCLUSIONS

A novel series of flavonoids were synthesized from the natural flavonoid, hesperetin, including 17 new compounds. Screening tests indicated that most of these compounds reduced NO production in LPS-stimulated murine macrophages at concentrations of 15 to 60 μM, and the inhibition generally increased in a dose-dependent manner. Some compounds showed different degrees of cytotoxicity on the human TBNC cell lines, SUM 149.

Exploring the bacterial community succession and metabolic profiles of Lonicera japonica Thunb. residues during anaerobic fermentation

Discarding Lonicera japonica Thunb. (LJT) residues containing many active metabolites create tremendous waste. This study aimed to effectively use LJT residues by anaerobic fermentation. Fermentation significantly decreased the pH values and reduced the abundance of undesirable bacteria (potential pathogenic and biofilm-forming) while increasing Lactobacillus abundance. Compound additive use further improved fermentation quality (significantly increased the lactic acid (LA) content and decreased the pH values and ammonia nitrogen (a-N) content) and nutrient quality (significantly decreased the acid detergent fiber (ADF) content and increased the water-soluble carbohydrate (WSC) content) and optimized the microbial community (increased the Lactobacillus abundance). Fermentation also altered the flavonoids, alkaloids and phenols contents in the residues with minor effects on the functional metabolites amounts. The LJT residues metabolic profile was mainly attributed to its epiphytic bacteria, with a small contribution from the compound additive. Thus, compound additives may improve anaerobic LJT residue fermentation without functionally impairing the metabolites.

Phenolic Profile and the Antioxidant, Anti-Inflammatory, and Antimicrobial Properties of Açaí (Euterpe oleracea) Meal: A Prospective Study

The mechanical extraction of oils from Brazilian açaí (Euterpe oleracea Mart) produces significant amounts of a byproduct known as "meal", which is frequently discarded in the environment as waste material. Nevertheless, plant byproducts, especially those from oil extraction, may contain residual polyphenols in their composition and be a rich source of natural bioactive compounds. In this study, the phenolic composition and in vitro biological properties of a hydroethanolic açaí meal extract were elucidated. The major compounds tentatively identified in the extract by high-resolution mass spectrometry were anthocyanins, flavones, and flavonoids. Furthermore, rhamnocitrin is reported in an açaí byproduct for the first time. The extract showed reducing power and was effective in scavenging the ABTS radical cation (820.0 µmol Trolox equivalent∙g^-1) and peroxyl radical (975.7 µmol Trolox equivalent∙g^-1). NF-κB activation was inhibited at 10 or 100 µg∙mL^-1 and TNF-α levels were reduced at 100 µg∙mL^-1. However, the antibacterial effects against ESKAPE pathogens was not promising due to the high concentration needed (1250 or 2500 µg∙mL^-1). These findings can be related to the diverse polyphenol-rich extract composition. To conclude, the polyphenol-rich extract obtained from açaí meal showed relevant biological activities that may have great applicability in the food and nutraceutical industries.

Potential metabolites of Arecaceae family for the natural anti-osteoarthritis medicine: A review

Osteoarthritis (OA) is a chronic inflammatory disorder of the joints caused by fluid and cartilage matrix component reduction. This disease results in symptoms of pain, deformity, and limitation of movement. In general, OA is treated with anti-inflammatory drugs and chondroprotection compounds, includes natural nutraceutical ingredients, which are expected to be effective and have minimal side effects. Arecaceae plants are widely spread worldwide, especially in tropical areas. The objective of this review is to collect information about the Arecaceae family as anti-OA agents, with the main study focusing on the primary and secondary metabolites of plants of the Arecaceae family, i.e., sugar palm (Arenga pinnata), nipa palm (Nypa fruticans), palmyra palm (Borassus flabellifer), date palm (Phoenix dactylifera), and betel nut (Areca catechu) have potential as anti-OA agents. The Arecaceae's metabolites that show anti-inflammatory and chondroprotective effects are galactomannan, fatty acids (linoleic and linolenic acids), flavonoids (quercetin, luteolin, isorhamnetin), phenolics (coumaric acid, ferulic acid), polyphenols (epicatechin), and steroids (stigmasterol, campesterol, spirostane). Based on the reports, the Arecaceae family plants become worthy of being explored and developed into natural anti-OA products, such as supplements or nutraceuticals.

Flavonoids as Antidiabetic and Anti-Inflammatory Agents: A Review on Structural Activity Relationship-Based Studies and Meta-Analysis

Flavonoids are a group of naturally occurring polyphenolic secondary metabolites which have been reported to demonstrate a wide range of pharmacological properties, most importantly, antidiabetic and anti-inflammatory effects. The relationship between hyperglycaemia and inflammation and vascular complications in diabetes is now well established. Flavonoids possessing antidiabetic properties may alleviate inflammation by reducing hyperglycaemia through different mechanisms of action. It has been suggested that the flavonoids’ biochemical properties are structure-dependent; however, they are yet to be thoroughly grasped. Hence, the main aim of this review is to understand the antidiabetic and anti-inflammatory properties of various structurally diverse flavonoids and to identify key positions responsible for the effects, their correlation, and the effect of different substitutions on both antidiabetic and anti-inflammatory properties. The general requirement of flavonoids for exerting both anti-inflammatory and antidiabetic effects is found to be the presence of a C2–C3 double bond (C-ring) and hydroxyl groups at the C3’, C4’, C5, and C7 positions of both rings A and B of a flavonoid skeleton. Furthermore, it has been demonstrated that substitution at the C3 position of a C-ring decreases the anti-inflammatory action of flavonoids while enhancing their antidiabetic activity. Correlation is discussed at length to support flavonoids possessing essential pharmacophores to demonstrate equipotent effects. The consideration of these structural features may play an important role in synthesizing better flavonoid-based drugs possessing dual antidiabetic and anti-inflammatory effects. A meta-analysis further established the role of flavonoids as antidiabetic and anti-inflammatory agents.

In Vitro Induction of Apoptosis in Isolated Acute Myeloid Leukemia Cells: The Role of Anastatica hierochuntica Methanolic Extract

Anastatica hierochuntica L. (Cruciferae) has been known in Egyptian folk medicine as a remedy for gastrointestinal disorders, diabetes and heart diseases. Despite the wide usage, A. hierochuntica research provides insufficient data to support its traditional practice. The cytotoxicity of A. hierochuntica methanolic extract was investigated on acute myeloid leukemia blasts (AML) and normal human peripheral leucocytes (NHPL). The phytochemical identification of bioactive compounds using ¹H-NMR and LC-ESI-MS was also performed. A. hierochuntica extract caused non-significant cytotoxicity on NHPL, while the cytotoxicity on AML was significant (IC₅₀: 0.38 ± 0.02 μg/mL). The negative expression of p53, upregulation of Caspase-3 and increase in the BAX/BCL-2 ratio were reported at the protein and mRNA levels. The results suggest that A. hierochuntica extract induced AML cell death via the p53-independent mitochondrial intrinsic pathway and further attention should be paid to this plant as a promising natural anticancer agent.

Preparation of a new component group of Ginkgo biloba leaves and investigation of the antihypertensive effects in spontaneously hypertensive rats

Ginkgo (Ginkgo biloba L.) is a traditional economic tree species in China. Ginkgo biloba extract (GBE) is widely used in combination to treat hypertension and complications in clinical practice. However, the antihypertensive effect of GBE alone is weak and it is also difficult to study the mechanism because of its complex composition. This study was to prepare a new component group of Ginkgo biloba leaves (GBLCG) with clear chemical structures, and to investigate its effect on reducing blood pressure and improving myocardial hypertrophy in spontaneously hypertensive rats with GBE and amlodipine as positive controls. The results showed that total flavonoid aglycones (TFAs) of GBLCG was mainly composed of quercetin (QCT), kaempferol (KMF) and isorhamnetin (ISR); Total terpenoid lactones (TTLs) of GBLCG might be a novel cocrystal composed of Ginkgolide A (GA), Ginkgolide B (GB) Ginkgolide C (GC), Ginkgolide J (GJ) and bilobalide (BB). The hypotensive activity of GBLCG (4.4 mg/kg) group was better than that of GBE group (p < 0.05), and the effect of improving myocardial hypertrophy was better than that of amlodipine besylate group (p < 0.01). GBLCG might reduce blood pressure and improve myocardial hypertrophy by promoting the synthesis and release of NO in endothelial cells, reducing oxidative stress, inhibiting platelet aggregation and promoting lesion circulation. Eventually, we hope to introduce GBLCG as a new drug for hypertension.

Deciphering the Underlying Mechanisms of Formula Le-Cao-Shi Against Liver Injuries by Integrating Network Pharmacology, Metabonomics, and Experimental Validation

Le-Cao-Shi (LCS) has long been used as a folk traditional Chinese medicine formula against liver injuries, whereas its pharmacological mechanisms remain elusive. Our study aims to investigate the underlying mechanism of LCS in treating liver injuries via integrated network pharmacology, metabonomics, and experimental validation. By network pharmacology, 57 compounds were screened as candidate compounds based on ADME parameters from the LCS compound bank (213 compounds collected from the literature of three single herbs). According to online compound–target databases, the aforementioned candidate compounds were predicted to target 87 potential targets related to liver injuries. More than 15 pathways connected with these potential targets were considered vital pathways in collectively modulating liver injuries, which were found to be relevant to cancer, xenobiotic metabolism by cytochrome P450 enzymes, bile secretion, inflammation, and antioxidation. Metabonomics analysis by using the supernatant of the rat liver homogenate with UPLC-Q-TOF/MS demonstrated that 18 potential biomarkers could be regulated by LCS, which was closely related to linoleic acid metabolism, glutathione metabolism, cysteine and methionine metabolism, and glycerophospholipid metabolism pathways. Linoleic acid metabolism and glutathione metabolism pathways were two key common pathways in both network pharmacology and metabonomics analysis. In ELISA experiments with the CCl₄-induced rat liver injury model, LCS was found to significantly reduce the levels of inflammatory parameters, decrease liver malondialdehyde (MDA) levels, and enhance the activities of hepatic antioxidant enzymes, which validated that LCS could inhibit liver injuries through anti-inflammatory property and by suppressing lipid peroxidation and improving the antioxidant defense system. Our work could provide new insights into the underlying pharmacological mechanisms of LCS against liver injuries, which is beneficial for its further investigation and modernization.

Capsicum Leaves under Stress: Using Multi-Omics Analysis to Detect Abiotic Stress Network of Secondary Metabolism in Two Species

The plant kingdom contains an enormous diversity of bioactive compounds which regulate plant growth and defends against biotic and abiotic stress. Some of these compounds, like flavonoids, have properties which are health supporting and relevant for industrial use. Many of these valuable compounds are synthesized in various pepper (Capsicum sp.) tissues. Further, a huge amount of biomass residual remains from pepper production after harvest, which provides an important opportunity to extract these metabolites and optimize the utilization of crops. Moreover, abiotic stresses induce the synthesis of such metabolites as a defense mechanism. Two different Capsicum species were therefore exposed to chilling temperature (24/18 ℃ vs. 18/12 ℃), to salinity (200 mM NaCl), or a combination thereof for 1, 7 and 14 days to investigate the effect of these stresses on the metabolome and transcriptome profiles of their leaves. Both profiles in both species responded to all stresses with an increase over time. All stresses resulted in repression of photosynthesis genes. Stress involving chilling temperature induced secondary metabolism whereas stresses involving salt repressed cell wall modification and solute transport. The metabolome analysis annotated putatively many health stimulating flavonoids (apigetrin, rutin, kaempferol, luteolin and quercetin) in the Capsicum biomass residuals, which were induced in response to salinity, chilling temperature or a combination thereof, and supported by related structural genes of the secondary metabolism in the network analysis.

Plectranthus ecklonii Benth: A Comprehensive Review Into its Phytochemistry and Exerted Biological Activities

Ethnopharmacological Relevance: Plectranthus genus (Lamiaceae family) contain several species with acknowledged ethnopharmacological uses, such as, for gastrointestinal and respiratory-related problems, due to their anti-inflammatory, antibacterial and antifungal properties. The bioactivity of isolated medicinal compounds from this genus justifies the increased interest in recent times for species of Plectranthus, placing them in the spotlight for natural product drug development. Aim of the study: To the best of our knowledge, this is the first review on the biological activities of Plectranthus ecklonii Benth. As such, the aim of this review was three-fold: 1) to summarize the chemical compounds isolated from P. ecklonii; 2) to collate the biological activities and mechanisms of action of these compounds from in vitro studies; and 3) to evaluate the documented uses and potential applications of this species, in order to postulate on the direction of pharmaceutical uses of this species. Materials and methods: An extensive database retrieval was performed using the electronic databases Web of Science, PubMed, Google Scholar and ScienceDirect. The search criteria consisted of the keywords "Plectranthus ecklonii", "Plectranthus ecklonii + review", "Plectranthus ecklonii + diterpenes" or "Plectranthus ecklonii + abietanes", "ecklonii + parviflorone D", searched individually and as combinations. Eligibility criteria were set out and titles in English, Portuguese and Spanish were reviewed, with all references included dating from 1970 to 2021. A total of 169 papers were selected and included. Chemical structures were drawn using ChemDraw 20.0, CID numbers were searched in PubChem and the PRISMA diagram was created using PowerPoint 2012. Results: To date, a total of 28 compounds have been isolated from P. ecklonii, including diterpenes, triterpenes, flavonoids, and hydroxycinnamic acids. Most focused on the antimicrobial action of its constituents, although compounds have demonstrated other bioactivities, namely antioxidant, anti-inflammatory and antitumor. The most recent studies emphasize the diterpenoids, particularly parviflorone D, with the help of nanotechnology. Conclusions: The widespread ethnobotanical and traditional uses of P. ecklonii can be scientifically justified by a range of biological activities, demonstrated by isolated secondary metabolites. These bioactivities showcase the potential of this species in the development of economically important active pharmaceutical ingredients, particularly in anticancer therapy.

A Catalog of Natural Products Occurring in Watermelon-Citrullus lanatus

Sweet dessert watermelon (Citrullus lanatus) is one of the most important vegetable crops consumed throughout the world. The chemical composition of watermelon provides both high nutritional value and various health benefits. The present manuscript introduces a catalog of 1,679 small molecules occurring in the watermelon and their cheminformatics analysis for diverse features. In this catalog, the phytochemicals are associated with the literature describing their presence in the watermelon plant, and when possible, concentration values in various plant parts (flesh, seeds, leaves, roots, rind). Also cataloged are the chemical classes, molecular weight and formula, chemical structure, and certain physical and chemical properties for each phytochemical. In our view, knowing precisely what is in what we eat, as this catalog does for watermelon, supports both the rationale for certain controlled feeding studies in the field of precision nutrition, and plant breeding efforts for the development of new varieties with enhanced concentrations of specific phytochemicals. Additionally, improved and comprehensive collections of natural products accessible to the public will be especially useful to researchers in nutrition, cheminformatics, bioinformatics, and drug development, among other disciplines.

Luteolin and apigenin derived glycosides from Alphonsea elliptica abrogate LPS-induced inflammatory responses in human plasma

ETHNOPHARMACOLOGICAL RELEVANCE

Numerous Alphonsea species including Alphonsea elliptica (mempisang) leaves and fruits are indigenously used in inflammatory conditions such as postpartum swelling and rheumatism in southeast Asian countries. In our previous in-vitro findings, A. elliptica methanol extract exhibited platelet-activating factor inhibition, suggesting the presence of phyto-constituents with anti-inflammatory potential.

AIM OF THE STUDY

However, so far there is no literature available on the anti-inflammatory activity of this species. Henceforth, based on the above background and our previous laboratory findings, we hypothesize that phytoconstituents of A. elliptica could possess anti-inflammatory potential against inflammatory mediators including prostaglandin-E₂ (PGE₂), cyclooxegenase-2 (COX-2) and cytokines (IL-1β and IL-6).

MATERIALS AND METHODS

Vacuum and column chromatography techniques were employed for the isolation of phytoconstituents. The structure elucidation was carried out using HRESI-MS, ¹H and ¹³C-NMR analysis and compared with the published literature. For cytotoxicity analysis, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay was performed on peripheral blood mononuclear cells. In-vitro anti-inflammatory activities were evaluated against the levels of PGE₂, COX-2, IL-1β and IL-6 in lipopolysaccharide (LPS)-induced human plasma using enzyme-linked immunosorbent assay and radioimmunoassay.

RESULTS

Unprecedentedly, chromatographic purification of methanolic leaves extract afforded five flavones namely vitexin, isovitexin, orientin, isoorientin, schaftoside with three flavanols; kaempferol, myricetin and rutin from A elliptica. In cell viability analysis, isolates did not present cytotoxicity up to 50 μM. In anti-inflammatory evaluation, orientin and isoorientin exhibited strong (≥70%), while isovitexin and vitexin produced strong to moderate (50-69%) PGE₂, COX-2, IL-1β and IL-6 inhibition at 25 and 50 μM. Isoorientin, orientin, isovitexin, and vitexin showed significant (p < 0.05) and concentration-dependent PGE₂ inhibition with IC₅₀ values (μM) of 11.40, 14.71, 17.70 and 20.58 against indomethacin (8.80). Furthermore, isoorientin, orientin, isovitexin, and vitexin produced significant concentration-dependent inhibition with IC₅₀ values (μM) of COX-2: 7.13, 9.51, 12.81, 16.61; IL-1β 4.80, 6.20, 10.85, 14.51; IL-6: 4.01, 5.90, 11.51 and 14.88 as compared to dexamethasone: 5.29, 2.93, 3.72, respectively (p < 0.05).

CONCLUSION

Conclusively, isolated phytoconstituents are reported for the first time from the A. elliptica. Moreover, isovitexin, vitexin orientin and isoorientin abrogated LPS-induced inflammatory responses in human plasma at non-cytotoxic concentrations.

Cynaroside prevents macrophage polarization into pro-inflammatory phenotype and alleviates cecal ligation and puncture-induced liver injury by targeting PKM2/HIF-1α axis

The treatment of sepsis is still challenging and the liver is an important target of sepsis-related injury. Macrophages are important innate immune cells in liver, and modulation of macrophages M1/M2 polarization may be a promising strategy for septic liver injury treatment. Macrophage polarization and inflammation of liver tissue has been shown regulated by pyruvate kinase M2 (PKM2)-mediated aerobic glycolysis and immune inflammatory pathways. Therefore, modulating PKM2-mediated immunometabolic reprogramming presents a novel strategy for inflammation-associated diseases. In this study, cynaroside, a flavonoid compound, promoted macrophage phenotypic transition from pro-inflammatory M1 to anti-inflammatory M2, and mitigated sepsis-associated liver inflammatory damage. We established that cynaroside reduced binding of PKM2 to hypoxia-inducible factor-1α (HIF-1α) by abolishing translocation of PKM2 to the nucleus and promoting PKM2 tetramer formation, as well as suppressing phosphorylation of PKM2 at Y105 in vivo and in vitro. Moreover, cynaroside restored pyruvate kinase activity, inhibited glycolysis-related proteins including PFKFB3, HK2 and HIF-1α, and inhibited glycolysis-related hyperacetylation of HMGB1 in septic liver. Therefore, this study reports a novel function of cynaroside in hepatic macrophage polarization, and cecum ligation and puncture-induced liver injury in septic mice. The findings provide crucial information with regard to therapeutic efficacy of cynaroside in the treatment of sepsis.

Effects of Aloe vera Flower Extract and Its Active Constituent Isoorientin on Skin Moisturization via Regulating Involucrin Expression: In Vitro and Molecular Docking Studies

Skin moisturization is very crucial for maintaining the flexibility, viscoelasticity, and differentiation of the epidermis and its deprivation causes several diseases from dry skin to dermatitis. Aloe vera, a miracle plant having diverse medicinal properties including skin moisturization effects. This study investigated for the first time the molecular mechanism targeting skin moisturization effects of the Aloe vera flower and its major active constituent. By treating human epidermal keratinocytes (HaCaT cells) with Aloe vera flower water extract (AFWE), we found that AFWE upregulated epidermal involucrin by activating the expression of protein kinase C, p38, and ERK 1/2. Additionally, it modulated filaggrin, increased aquaporin expression, and hyaluronan synthesis via a balanced regulation of HAS1 and HYAL1 protein. Similarly, it was able to protect UVB-induced photodamage. Western blot analysis, ELISA, and qRT- PCR were performed to evaluate various epidermal differentiation markers and moisturization-related factors on human epidermal keratinocytes (HaCaT cells). TLC and HPLC were used to detect and analyze the chemical constituents. Among them, we found that an active component of Aloe vera flower, isoorientin (IO) has a high binding affinity to all of its targeted proteins such as involucrin, PKC, P38, etc. through molecular docking assay. This study indicated that the Aloe vera flower and its active constituent, IO can be used as a prominent ingredient to enhance skin barrier function and improve its related pathologies.

Ethnopharmacology, Phytochemistry and Biological Activities of Native Chilean Plants

The native flora of Chile has unique characteristics due to the geographical situation of the country, with the vast desert in the North, Patagonia in the South, the Andean Mountains on the east and the Pacific Ocean on the west. This exclusivity is reflected in high concentrations of phytochemicals in the fruits and leaves of its native plants. Some examples are Aristotelia chilensis (Molina), Stuntz (maqui), Berberis microphylla G. Forst. (calafate), Peumus boldus Molina (boldo), Ribes magellanicum Poir. (Magellan currant), Ugni molinae Turcz. (murtilla), Rubus geoides Sm. (miñe miñe), Drimys winteri J.R.Forst. & G.Forst. (canelo), Luma apiculata (DC.) Burret (arrayán) distributed throughout the entire Chilean territory. Some of these Chilean plants have been used for centuries in the country's traditional medicine. The most recent studies of phytochemical characterization of parts of Chilean plants show a wide spectrum of antioxidant compounds, phenolic components, terpenoids and alkaloids, which have shown biological activity in both in vitro and in vivo studies. This manuscript covers the entire Chilean territory characterizing the phytochemical profile and reporting some of its biological properties, focusing mainly on antioxidant, anti-inflammatory, antimicrobial, chemopreventive and cytotoxic activity, and potential against diabetes, metabolic syndrome and gastrointestinal disorders.

Role of luteolin in overcoming Parkinson's disease

Parkinson's disease (PD) is the second most common neurodegenerative disorder affecting elderly people (>60 years old) worldwide. There is no permanent cure for the disease but the symptomatic relief can be obtained by using dopamine agonists besides L-dopa therapy. The longer use of the drugs is associated with several side effects. Hence, the researchers have made a considerable attention toward the development of neuroprotective agents from plants. A number of phytochemicals have been demonstrated for their protective effects in various in vitro, in vivo, and clinical studies. In this context, luteolin, a flavone which is present in fruits and vegetables has been attributed to a number of pharmacological properties including neuroprotective. The present review demonstrates the bioavailability, oral absorption, and mechanism of action against PD.

Cynaroside inhibits Leishmania donovani UDP-galactopyranose mutase and induces reactive oxygen species to exert antileishmanial response

Cynaroside, a flavonoid, has been shown to have antibacterial, antifungal and anticancer activities. Here, we evaluated its antileishmanial properties and its mechanism of action through different in silico and in vitro assays. Cynaroside exhibited antileishmanial activity in time- and dose-dependent manner with 50% of inhibitory concentration (IC₅₀) value of 49.49 ± 3.515 µM in vitro. It inhibited the growth of parasite significantly at only 20 µM concentration when used in combination with miltefosine, a standard drug which has very high toxicity. It also inhibited the intra-macrophagic parasite significantly at low doses when used in combination with miltefosine. It showed less toxicity than the existing antileishmanial drug, miltefosine at similar doses. Propidium iodide staining showed that cynaroside inhibited the parasites in G₀/G₁ phase of cell cycle. 2,7-dichloro dihydro fluorescein diacetate (H₂DCFDA) staining showed cynaroside induced antileishmanial activity through reactive oxygen species (ROS) generation in parasites. Molecular-docking studies with key drug targets of Leishmania donovani showed significant inhibition. Out of these targets, cynaroside showed strongest affinity with uridine diphosphate (UDP)-galactopyranose mutase with −10.4 kcal/mol which was further validated by molecular dynamics (MD) simulation. The bioactivity, ADMET (absorption, distribution, metabolism, excretion and toxicity) properties, Organisation for Economic Co-operation and Development (OECD) chemical classification and toxicity risk prediction showed cynaroside as an enzyme inhibitor having sufficient solubility and non-toxic properties. In conclusion, cynaroside may be used alone or in combination with existing drug, miltefosine to control leishmaniasis with less cytotoxicity.

Next Chapter in the Legend of Silphion: Preliminary Morphological, Chemical, Biological and Pharmacological Evaluations, Initial Conservation Studies, and Reassessment of the Regional Extinction Event

Silphion was an ancient medicinal gum-resin; most likely obtained from a Ferula species growing in the Cyrene region of Libya ca. 2500 years ago. Due to its therapeutic properties and culinary value, silphion became the main economic commodity of the Cyrene region. It is generally believed that the source of silphion became extinct in the first century AD. However, there are a few references in the literature about the cultivated silphion plant and its existence up to the fifth century. Recently, a rare and endemic Ferula species that produces a pleasant-smelling gum-resin was found in three locations near formerly Greek villages in Anatolia. Morphologic features of this species closely resemble silphion, as it appears in the numismatic figures of antique Cyrenaic coins, and conform to descriptions by ancient authors. Initial chemical and pharmacological investigations of this species have confirmed the medicinal and spice-like quality of its gum-resin supporting a connection with the long-lost silphion. A preliminary conservation study has been initiated at the growth site of this rare endemic Ferula species. The results of this study and their implications on the regional extinction event, and future development of this species will be discussed.

Isoorientin: A dietary flavone with the potential to ameliorate diverse metabolic complications

Isoorientin is a natural C-glucosyl flavone that is generating a lot of interest due to its multiple pharmacological activities. Increasing experimental data have shown that the robust antioxidant and anti-inflammatory properties of isoorientin remain important in ameliorating a number of metabolic complications. In fact, plants rich in isoorientin have demonstrated strong ameliorative properties against complications such as hyperglycemia, hyperlipidemia, and insulin resistance. However, while such evidence is accumulating, it has not been reviewed to better inform on the therapeutic potential of this flavone in improving human health. This review examines and extrapolates available literature on the potential beneficial or detrimental effects associated with the use of isoorientin in mitigating metabolic diseases, with a specific focus on diabetes, obesity, and insulin resistance, including associated complications. The discussion includes effective doses in various experimental settings and proposed molecular mechanisms by which isoorientin may exert its therapeutic effects. In addition, the protective effects of extracts of a number of isoorientin-rich plants against metabolic complications will be highlighted.

Phenolic Composition of the Leaves of Pyrola rotundifolia L. and Their Antioxidant and Cytotoxic Activity

The leaves of Pyrola rotundifolia L. were extracted in the mixed solvent of methanol/acetone/water (2:2:1, v/v/v) and investigated for their phytochemical analysis and biological activity. Total phenolic and flavonoid contents were determined spectrophotometrically. A high content of phenols (208.35 mg GAE/g of dry extract), flavonoids (38.90 mg QE/g of dry extract) and gallotannins (722.91 GAE/g of dry extract) was obtained. Ultra-high performance liquid chromatography diode array detector tandem mass spectrometry (UHPLC-DAD-MS) allowed for the detection of 23 major peaks at 254 nm. The extract was analyzed for its antioxidant capacity using 2,2-diphenyl-1-picryl-hydrazyl (DPPH^•) and 2,2'-azinobis[3-ethylbenzthiazoline]-6-sulfonic acid (ABTS^•+) radical scavenging, metal chelating power and β-carotene-linoleic acid bleaching assays. The examined extract showed moderate radical scavenging and chelating activity, and good inhibiting ability of linoleic acid oxidation (EC₅₀ = 0.05 mg/mL) in comparison to standards. The cytotoxic effect in increasing concentration on five types of leukemic cell lines was also investigated using trypan blue vital staining. It was found that the analyzed extract induced the apoptosis of all the tested cell lines. Our findings suggest that the leaves of P. rotundifolia are a source of valuable compounds providing protection against oxidative damage, hence their use in traditional medicine is justified.

Lonicerae japonicae flos and Lonicerae flos: a systematic review of ethnopharmacology, phytochemistry and pharmacology

Lonicerae japonicae flos (called Jinyinhua, JYH in Chinese), flowers or flower buds of Lonicera japonica Thunberg, is an extremely used traditional edible-medicinal herb. Pharmacological studies have already proved JYH ideal clinical therapeutic effects on inflammation and infectious diseases and prominent effects on multiple targets in vitro and in vivo, such as pro-inflammatory protein inducible nitric oxide synthase, toll-like receptor 4, interleukin-1 receptor. JYH and Lonicerae flos [called Shanyinhua, SYH in Chinese, flowers or flower buds of Lonicera hypoglauca Miquel, Lonicera confusa De Candolle or Lonicera macrantha (D.Don) Spreng] which belongs to the same family of JYH were once recorded as same herb in multiple versions of Chinese Pharmacopoeia (ChP). However, they were listed as two different herbs in 2005 Edition ChP, leading to endless controversy since they have close proximity on plant species, appearances and functions, together with traditional applications. In the past decades, there has no literature regarding to systematical comparison on the similarity concerning research achievements of the two herbs. This review comprehensively presents similarities and differences between JYH and SYH retrospectively, particularly proposing them the marked differences in botanies, phytochemistry and pharmacological activities which can be used as evidence of separate list of JYH and SYH. Furthermore, deficiencies on present studies have also been discussed so as to further research could use for reference.

Antagonistic Efficacy of Luteolin against Lead Acetate Exposure-Associated with Hepatotoxicity is Mediated via Antioxidant, Anti-Inflammatory, and Anti-Apoptotic Activities

The abundant use of lead (Pb; toxic heavy metal) worldwide has increased occupational and ecosystem exposure, with subsequent negative health effects. The flavonoid luteolin (LUT) found in many natural foodstuffs possesses antioxidant and anti-inflammatory properties. Herein, we hypothesized that LUT could mitigate liver damage induced by exposure to lead acetate (PbAc). Male Wistar rats were allocated to four groups: control group received normal saline, LUT-treated group (50 mg/kg, oral, daily), PbAc-treated group (20 mg/kg, i.p., daily), and LUT+PbAc-treated group (received the aforementioned doses via the respective routes of administration); the rats were treated for 7 days. The results revealed that PbAc exposure significantly increased hepatic Pb residue and serum activities of aspartate aminotransferase (AST), alanine aminotransferase (ALT), and total bilirubin value. Oxidative reactions were observed in the liver tissue following PbAc intoxication, characterized by the depletion and downregulation of antioxidant proteins (glutathione, glutathione reductase, glutathione peroxidase, superoxide dismutase, catalase, nuclear factor erythroid 2-related factor 2, and heme oxygenase-1), and an increase in oxidants (malondialdehyde and nitric oxide). Additionally, PbAc increased the release and expression of the pro-inflammatory cytokines (tumor necrosis factor alpha and interleukin-1 beta), inducible nitric oxide synthase, and nuclear factor kappa B. Moreover, PbAc enhanced hepatocyte loss by increasing the expression of pro-apoptotic proteins (Bax and caspase-3) and downregulating the anti-apoptotic protein (Bcl-2). The changes in the aforementioned parameters were further confirmed by noticeable histopathological lesions. LUT supplementation significantly reversed all of the tested parameters in comparison with the PbAc-exposed group. In conclusion, our findings describe the potential mechanisms involved in the alleviation of PbAc-induced liver injury by luteolin via its potent anti-inflammatory, antioxidant, and anti-apoptotic properties.

Luteolin improves heart preservation through inhibiting hypoxia-dependent L-type calcium channels in cardiomyocytes

The current study aimed to evaluate whether luteolin could improve long-term heart preservation; this was achieved by evaluating the heart following long-term storage in University of Wisconsin solution (the control group) and in solutions containing three luteolin concentrations. The effects of different preservation methods were evaluated with respect to cardiac function while hearts were in custom-made ex vivo Langendorff perfusion systems. Different preservation methods were evaluated with respect to the histology, ultrastructure and apoptosis rate of the hearts, and the function of cardiomyocytes. In the presence of luteolin, the rate pressure product of the left ventricle was increased within 60 min of reperfusion following a 12-h preservation, coronary flow was higher within 30 min of reperfusion, cardiac contractile function was higher throughout reperfusion following 12- and 18-h preservations, and the left ventricle peak systolic pressure was significantly higher compared with the control group (all P<0.05). The expression levels of apoptosis regulator Bax and apoptosis regulator Bcl-2 in the luteolin groups were significantly decreased and increased, respectively. Lactate dehydrogenase, creatine kinase and malondialdehyde enzymatic activity was increased following long-term storage, while the activity of superoxide dismutase was significantly decreased. Furthermore, luteolin inhibited L-type calcium currents in ventricular myocytes under hypoxia conditions. Thus, luteolin demonstrated protective effects during long-term heart preservation in what appeared to be a dose-dependent manner, which may be accomplished through inhibiting hypoxia-dependent L-type calcium channels.

Recent advances in topical delivery of flavonoids: A review

Flavonoids are one of the vital classes of bioactive chemicals, abundantly found in plants. These are natural polyphenolic compounds derived from plant metabolites. Their lipophilic nature and poor solubility lead to variable and limited oral bioavailability. The substantial pharmacological properties of flavonoids include antioxidant, anti-inflammatory, antiproliferative, photoprotective, depigmentation, anti-aging which are very promising in the treatment of several skin disorders. Thus, various topical delivery systems of flavonoids have been extensively studied. Mostly, colloidal carriers of flavonoids were reported which are very efficient for topical route with good encapsulation potential, reduced toxicity, and overcome the limitations of conventional dosage forms. This review focuses on various formulations aspects, in vitro characterization and in vivo studies of different classes of flavonoids administered by topical route. Although flavonoids offer tremendous potential in healing the skin conditions categorically, its clinical translation needs in depth safety and efficacy data, meeting established regulatory standards.

Complexation of luteolin with lead (II): Spectroscopy characterization and theoretical researches

The interactions of (CH₃COO)₂Pb·3H₂O (lead acetate trihydrate) with luteolin, 5,7,3',4'-tetrahydroxyflavone, were investigated in methanol solution. The spectroscopy (UV-Vis, FT-IR, HPLC-MS, ¹H NMR) and elemental analysis were adopted to assess the interaction of luteolin and Pb(II). The results show that luteolin reacts with Pb(II) through the chelating sites of 4‑carbonyl and 5-hydroxy in two luteolin molecules. The structures, energies, CDA (charge decomposition analysis) and orbitals analysis of the ligand and complex have been analyzed according to quantum-chemical calculation, which is further proofed that luteolin molecule can effectively chelate Pb(II) by 5-hydroxyl-4-oxo chelating site. It is speculated that luteolin has a high potential of becoming a health care product to eliminate lead cation in the future.

Biophenols: Enzymes (β-secretase, Cholinesterases, histone deacetylase and tyrosinase) inhibitors from olive (Olea europaea L.)

The focus of this study was on inhibition of enzymes involved in the pathogenesis Alzheimer's disease (AD) including prime amyloid beta (Aβ) producing enzyme (β-secretase: BACE-1) and disease progression enzymes including acetylcholinesterase (AChE), butyrylcholinesterase (BChE), histone deacetylase (HDAC), and tyrosinase along with the catecholamine L-DOPA, by using olive biophenols. Here we report the strongest inhibition of BACE-1 from rutin (IC₅₀: 3.8 nM) followed by verbascoside (IC₅₀: 6.3 nM) and olive fruit extract (IC₅₀: 18 ng), respectively. Olive biophenol, quercetin exhibited strongest enzyme inhibitory activity against tyrosinase (IC₅₀: 10.73 μM), BChE (IC₅₀: 19.08 μM), AChE (IC₅₀: 55.44 μM), and HDAC (IC₅₀: 105.1 μM) enzymes. Furthermore, olive biophenol verbascoside (IC₅₀: 188.6 μM), and hydroxytyrosol extreme extract (IC₅₀: 66.22 μg) were showed the highest levels of inhibition against the HDAC enzyme. Neuroprotective capacity against levodopa-induced toxicity in neuroblastoma (SH-SY5Y) cells of olive biophenols were assessed, where rutin indicated the highest neuroprotection (74%), followed by caffeic acid (73%), and extract hydroxytyrosol extreme (97%), respectively. To the best of our knowledge, this is the first in vitro report on the enzymes inhibitory activity of olive biophenols. Taken together, our in vitro results data suggest that olive biophenols could be a promising natural inhibitor, which may reduce the enzyme-induced toxicity associated with the oxidative stress involved in the progression of AD.

CHEMICAL COMPOUNDS USED IN THE STUDY

Acetylthiocholine iodide (PubChem CID: 74629); S-Butyrylthiocholine chloride (PubChem CID: 3015121); Caffeic acid (PubChem CID: 689043); Dimethyl sulfoxide (DMSO) (PubChem: 679); L-3,4-Dihydroxyphenylalanine (L-DOPA) (PubChem CID: 6047); 5,5'-Dithiobis (2-nitrobenzoic acid) (DTNB) (PubChem CID: 6254); Epigallocatechin gallate (EGCG) (PubChem CID: 65064); Ethylenediamine tetraacetic acid (EDTA) (PubChem CID: 6049); Galantamine hydrobromide (PubChem CID: 121587); l-Glutamine (PubChem CID: 5961); Hydroxytyrosol (PubChem CID: 82755); Kojic acid (PubChem CID: 3840); Luteolin (PubChem CID: 5280445); Oleuropein (PubChem CID: 5281544); Penicillin-streptomycin (PubChem CID: 131715954); Quercetin (PubChem CID: 5280343); Rutin (PubChem CID: 5280805); Tris-HCl buffer (PubChem: 93573); Trypan blue (PubChem: 9562061).

The mutagenic and antimutagenic activity of Sutherlandia frutescens extracts and marker compounds

BACKGROUND

Sutherlandia frutescens (L.) R. Br is endemic to Southern Africa where it has been traditionally used for cancer and diabetes. In recent times it has been marketed for its reputed (but not proven) anticancer, antidiabetic and anti-HIV properties. Little is known about the mutagenic and antimutagenic potential of extracts and common marker compounds of Sutherlandia frutescens. Therefore this study aimed to investigate the putative efficacy and possible long-term adverse effects of using this herb.

METHODS

Ethylacetate (EA) and 50% Methanol (MeOH) extracts were screened for mutagenic and antimutagenic activity using the Ames assay utilising TA97a, TA98, TA100 and TA102 in the presence and absence of metabolic activation. Four compounds, L-arginine, L-canavanine, GABA and D-pinitol known to occur in sutherlandia were also included. The total polyphenolic content of the both extracts was determined using the Folin-Ciocalteau method and FRAP and ABTS were used to determine the anti-oxidant potential of the extracts.

RESULTS

The extracts and the standards did not show any cytotoxicity except in TA97a. The EA extract exhibited antimutagenicity against all the bacterial strains at all concentrations tested. The MeOH extract showed both pro-mutagenic and antimutagenic activities with 2-acetamidofluorene and aflatoxin B1 in the presence of metabolic activation of TA98 and TA100, respectively. All compounds, except L-canavanine exhibited antimutagenic activity against all strains. L-canavanine, on the other hand showed co-mutagenicity with 9-aminoacridine on TA97a, at all test concentrations. The extracts and pure compounds exhibited their antimutagenic activity in a dose response manner. L-arginine and GABA showed an some antimutagenic response. EA extract had three times the total phenolic content (12.56 μg GE / mg) observed in the MeOH extract. There was correlation between total phenolic content, antioxidant potential and antimutagenicity.

CONCLUSION

Both extracts exhibited a protective effect, with the EA extract exhibiting greater potency. L-canavanine acted as a co-mutagen in a dose response manner without metabolic activation. It is suggested that the EA extract be priotized for future development work as it showed a better risk profile and activity.

Analytical Methods of Phytochemicals from the Genus Gentiana

The genus Gentiana comprises approximately 400 species. Many species have a wide range of pharmacological activities and have been used therapeutically for thousands of years. To provide comprehensive guidance, utilization and quality control of Gentiana species, this review presents updated information concerning the recent application and progress of chemical analysis including phytochemical analysis, sample preparation and chemometrics. Detailed and comprehensive data including number of analytes, extraction/separation methods, analytical techniques and chemometrics are shown as corresponding tables. These data illustrate that the development of newly discovered compounds and therapeutic uses, understanding of the structure-activity relationship and establishment of harmonious and effective medicinal herb standards are the direction of advancement in future research.

Hyperglycemia-induced oxidative stress and heart disease-cardioprotective effects of rooibos flavonoids and phenylpyruvic acid-2-O-β-D-glucoside

Diabetic patients are at an increased risk of developing heart failure when compared to their non-diabetic counter parts. Accumulative evidence suggests chronic hyperglycemia to be central in the development of myocardial infarction in these patients. At present, there are limited therapies aimed at specifically protecting the diabetic heart at risk from hyperglycemia-induced injury. Oxidative stress, through over production of free radical species, has been hypothesized to alter mitochondrial function and abnormally augment the activity of the NADPH oxidase enzyme system resulting in accelerated myocardial injury within a diabetic state. This has led to a dramatic increase in the exploration of plant-derived materials known to possess antioxidative properties. Several edible plants contain various natural constituents, including polyphenols that may counteract oxidative-induced tissue damage through their modulatory effects of intracellular signaling pathways. Rooibos, an indigenous South African plant, well-known for its use as herbal tea, is increasingly studied for its metabolic benefits. Prospective studies linking diet rich in polyphenols from rooibos to reduced diabetes associated cardiovascular complications have not been extensively assessed. Aspalathin, a flavonoid, and phenylpyruvic acid-2-O-β-D-glucoside, a phenolic precursor, are some of the major compounds found in rooibos that can ameliorate hyperglycemia-induced cardiomyocyte damage in vitro. While the latter has demonstrated potential to protect against cell apoptosis, the proposed mechanism of action of aspalathin is linked to its capacity to enhance the expression of nuclear factor (erythroid-derived 2)-like 2 (Nrf2) expression, an intracellular antioxidant response element. Thus, here we review literature on the potential cardioprotective properties of flavonoids and a phenylpropenoic acid found in rooibos against diabetes-induced oxidative injury.

Antioxidant and anti-inflammatory activities of the major phenolics from Zygophyllum simplex L

ETHNOPHARMACOLOGICAL RELEVANCE

Zygophyllum simplex L. is a halophyte plant that follows Zygophyllaceae. The plant is growing in arid and semiarid regions. It has been used traditionally in Arabic region to treat gout, asthma and inflammation.

AIM OF STUDY

Although ant-inflammatory activity has been reported for this plant, this study aimed to isolate and identify the major constituents of Zygophyllum simplex L., as well as assessing their antioxidant and anti-inflammatory activities in-vitro. In this study, the mechanism of anti-inflammatory activity of the isolated compounds was assessed.

MATERIALS AND METHODS

Defatted fraction of the total methanol extract of the aerial parts of Z. simplex was repeatedly chromatographed on Diaion HP-20, polyamide, and RP₁₈ columns to give five major phenolic compounds. The identity of the purified compounds was established by NMR experiments and comparing with previously known analogs. Moreover, the antioxidant and anti-inflammatory activities of the purified phenolics were investigated in-vitro through measuring of NFκB, PGE₂, IL-6, IL-1β and TNF-α levels in human peripheral blood mononuclear cells (PBMC) stimulated with phytohaemagglutinin (PHA).

RESULTS

Phytochemical investigation of the flowering aerial parts of Z. simplex resulted in isolation of five major metabolites identified as isorhamnetin-3-O-β-D-rutinoside (1), myricitrin (2), luteolin-7- O-β-D-glucoside (3), isorhamnetin-3-O-β-D-glucoside(4), and isorhamnetin (5). It is noteworthy to report that compounds 1-3 were isolated from the plant for the first time. It was reported that NFκB represents an important linkage between oxidative stress and inflammation. Compounds 2 and 3 have exhibited the highest antioxidant activity and showed the most efficient in decreasing NFκB p65 at the lowest concentration (1µM). Moreover; at 1µM concentrations, only compounds 2 and 3 significantly decreased IL-6, IL-1β and TNF-α levels from PHA treatment. Nevertheless, at 100µM, all isolated metabolites significantly decreased IL-6 compared to PHA treatment.

CONCLUSION

Five major phenolic compounds were isolated from Z. simplex. Anti-inflammatory activity exhibited by the isolated compounds augment the traditional use of this plant as anti-inflammatory. The effect was mediated via inhibition of NFκB through antioxidant mechanism and subsequent inhibition to other inflammatory mediators like TNF-α, IL-1β and IL-6.

Assessment of Phenolic Compounds and Anti-Inflammatory Activity of Ethyl Acetate Phase of Anacardium occidentale L. Bark

The bark of A. occidentale L. is rich in tannins. Studies have described various biological activities of the plant, including antimicrobial, antioxidant, antiulcerogenic and antiinflammatory actions. The objective of this study was to assess the activity of the ethyl acetate phase (EtOAc) of A. occidentale on acute inflammation and to identify and quantify its phenolic compounds by HPLC. The method was validated and shown to be linear, precise and accurate for catechin, epicatechin, epigallocatechin and gallic acid. Swiss albino mice (Mus musculus) were treated with saline, Carrageenan (2.5%), Indomethacin (10 mg/kg), Bradykinin (6 nmol) and Prostaglandine E2 (5 µg) at different concentrations of EtOAc - A. occidentale (12.5; 25; 50; and 100 mg/kg/weight p.o.) for the paw edema test. Challenge was performed with carrageenan (500 µg/mL i.p.) for the doses 50 and 100 mg/kg of EtOAc. Levels of cytokines IL-1, TNF-α, IL-6 and IL-10 were also measured. All EtOAc - A. occidentale concentrations reduced the edema. At 50 and 100 mg/kg, an anti-inflammatory response of the EtOAc was observed. Carrageenan stimulus produced a neutrophil count of 28.6% while 50 and 100 mg/kg of the phase reduced this to 14.5% and 9.1%, respectively. The EtOAc extract reduced levels of IL-1 and TNF-α. These results suggest that the EtOAc plays a modulatory role in the inflammatory response. The chromatographic method can be used for the analysis of the phenolic compounds of the EtOAc phase.

The ethyl acetate fraction from Physalis alkekengi inhibits LPS-induced pro-inflammatory mediators in BV2 cells and inflammatory pain in mice

ETHNOPHARMACOLOGICAL RELEVANCE

Physalis alkekengi is an edible herb whose fruit and calyx are traditionally used to treat a wide range of diseases including inflammation, toothache, and rheumatism. However, the effects of Physalis alkekengi fruit along with its calyx (PAF) on neuroinflammation and inflammatory pain behavior have not been reported yet.

AIM OF THE STUDY

This study evaluated the anti-inflammatory effect of PAF on lipopolysaccharide (LPS)-induced neuroinflammation and several in vivo model of inflammatory pain in mice.

MATERIALS AND METHODS

Here, first we studied the effects of PAF fractions on the production of pro-inflammatory mediators in LPS-treated BV2 microglial cells using enzyme-linked immunosorbent assay. The translocation of nuclear factor-kappa B (NF-κB) and the involvements of Akt and mitogen-activated protein (MAP) kinases in ethyl acetate fraction of PAF (PAF-EA)-mediated anti-inflammatory effect were measured using Western blotting. In in vivo experiments, the efficacy of PAF-EA was evaluated at the doses of 100 and 200mg/kg using several chemical-induced models of inflammatory pain such as acetic acid-induced writhing, formalin-induced paw licking and edema.

RESULTS

We found that compared to other fractions, the PAF-EA more potently inhibited the LPS-induced generation of nitric oxide, tumor necrosis factor-α, interleukin-6 and reactive oxygen species. It also inhibited LPS-induced nuclear translocation of NF-κB. These actions of EA fraction were found to be associated with a disruption of Akt and MAP kinases signaling pathways. The EA fraction also significantly inhibited acetic acid-induced writhing, formalin-induced licking time and edema in mice.

CONCLUSIONS

Our findings support the ethnopharmacological use of P. alkekengi fruit along with its calyx as an anti-inflammatory agent and suggest that the EA fraction of PAF may serve as a potential candidate to treat different neurological disorders and pain associated with inflammation.

Phenolic Profile and In vitro Antioxidant Activity of Endemic Bulgarian Carduus Species

Background:

Plant species from genus Carduus are widely distributed in the world and represented in Bulgaria by 14 species. Previous investigations on this genus demonstrated a strong antioxidant potential of extract from some Bulgarian Carduus species.

Objective:

The present study investigates the phenolic profile and the antioxidant potential of different extracts obtained from four endemic Compositae herbs, growing wild in Bulgaria: Carduus armatus Boiss and Heldr., Carduus candicans Waldst. et Kit ssp. globifer (Velen.) Kazmi., Carduus rhodopaeus Velen. and Carduus thracicus (Velen.) Hayek.

Materials and Methods:

Antioxidant capacity of the obtained extracts was estimated with 2,2-diphenyl-1-picrylhydrazyl, 2,2’-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid), and ferric reducing antioxidant power and copper reduction antioxidant assays. Phenolic profile was estimated by high performance liquid chromatography.

Results:

Eleven phenolic acids and eight flavonoids were quantified in the inflorescences. Sinapic (2760.72 ± 15.68 μg/g dry weight [dw]), chlorogenic (2564.50 ± 19.73 μg/g dw) and ferulic acids (1648.71 ± 19.57 μg/g dw), as well as luteolin (2345.45 ± 18.61 μg/g dw) and apigenin (1332.75 ± 12.05 μg/g dw) were found to be the predominant compounds. The above contents are the highest values found in C. candicans ssp. globifer. The highest established antioxidant activity (AOA) was in favor of the ethanolic extracts, and the extract of C. rhodopaeus affirmed with the highest AOA among the investigated plant species.

Conclusion:

All identified phenolic compounds were reported for the 1^st time in the studied endemic Carduus species, as well as their antioxidant capacities. The present study revealed that these plant species could be used as sources of antioxidants with potential medicinal properties.

SUMMARY

Phenolic acids and flavonoid profiles of four endemic compositae herbs, growing wild in Bulgaria: Carduus armatus, Carduus candicans ssp. globifer, Carduus rhodopaeus and Carduus thracicus, were quantified for the first time by high performance liquid chromatography (HPLC). Eleven phenolic acids and eight flavonoids were determined in the inflorescences. Sinapic, chlorogenic and ferulic acids, as well as luteolin and apigenin were found to be the predominant compounds. The highest values of established phenolic compounds were found in C. candicans ssp. globifer. The studied plant extracts of Carduus species possessed antioxidant activity in favor of C. rhodopaeus and results confirmed 70 % ethanol as more appropriate solvent. The present study revealed that these plant species could be used as sources of antioxidants with potential medicinal properties.

Bitter Gentian Teas: Nutritional and Phytochemical Profiles, Polysaccharide Characterisation and Bioactivity

As a result of the wide distribution of herbal teas the data on nutritional characterisation, chemical profile and biological activity of these products are required. The decoctions of Gentiana algida, G. decumbens, G. macrophylla and G. triflora herb teas were nutritionally characterized with respect to their macronutrients, demonstrating the predominance of polysaccharides and low lipid content. Gentian decoctions were also submitted to a microcolumn RP-HPLC-UV analysis of phytochemicals demonstrating a high content of iridoids (177.18-641.04 μg/mL) and flavonoids (89.15-405.71 μg/mL). Additionally, mangiferin was detected in samples of G. triflora tea (19.89 μg/mL). Five free sugars (fructose, glucose, sucrose, gentiobiose, gentianose) were identified in all gentian teas studied, as well as six organic acids (malic, citric, tartaric, oxalic, succinic, quinic). Pectic polysaccharides with a high content of rhamnogalacturonans and arabinogalactans were also identified and characterized in gentian decoctions for the first time. Gentian tea decoctions and their specific compounds (gentiopicroside, loganic acid-6'-O-β-d-glucoside, isoorientin, isoorientin-4'-O-β-d-glucoside, mangiferin, water-soluble polysaccharides) showed a promising antimicrobial, anti-inflammatory and antioxidant potentials. Evidences obtained indicate the prospective use of gentian herb teas as food products and medicines.

Anti-inflammatory and antipyretic properties of Kang 601 heji, a traditional Chinese oral liquid dosage form

Objective

To evaluate the scientific basis for the use of Kang 601 heji (K-601) as an anti-inflammatory and antipyretic agent using appropriate animal models.

Methods

Carrageenan-induced rat paw and xylene-induced ear oedemas were models used to investigate anti-inflammatory actions of K-601. Lipopolysaccharide-induced pyrexia model was used to evaluate antipyretic activity in Wistar rats. The anti-inflammatory and antipyretic mechanisms were evaluated by detecting prostaglandins E₂, nitric oxide, interleukin-1β and tumour necrosis factor-α levels using appropriate reagents and ELISA kits.

Results

The results revealed that K-601 reduced the level of inflammations in both anti-inflammatory models in a dose-dependent manner. The same was true for the antipyretic model. The possible mechanisms of actions were through the inhibition of prostaglandins E₂, interleukin-1β, tumour necrosis factor-α and nitric oxide.

Conclusions

K-601 has proven anti-inflammatory and antipyretic actions. The findings provide a scientific basis for the use of K-601 as anti-inflammatory and antipyretic agent in traditional Chinese medicinal practice.