Anti-inflammatory activities of essential oil isolated from the calyx of Hibiscus sabdariffa L

Potential Application of the Plant-Derived Essential Oils for Atherosclerosis Treatment: Molecular Mechanisms and Therapeutic Potential

Essential oils (EOs) are complex secondary metabolites identified in many plant species. Plant-derived EOs have been widely used in traditional medicine for centuries for their health-beneficial effects. Some EOs and their active ingredients have been reported to improve the cardiovascular system, in particular to provide an anti-atherosclerotic effect. The objective of this review is to highlight the recent research investigating the anti-inflammatory, anti-oxidative and lipid-lowering properties of plant-derived EOs and discuss their mechanisms of action. Also, recent clinical trials exploring anti-inflammatory and anti-oxidative activities of EOs are discussed. Future research on EOs has the potential to identify new bioactive compounds and invent new effective agents for treatment of atherosclerosis and related diseases such as diabetes, metabolic syndrome and obesity.

The Management of Diabetes Mellitus Using Medicinal Plants and Vitamins

Diabetes mellitus (DM) is a serious chronic metabolic disease that is associated with hyperglycemia and several complications including cardiovascular disease and chronic kidney disease. DM is caused by high levels of blood sugar in the body associated with the disruption of insulin metabolism and homeostasis. Over time, DM can induce life-threatening health problems such as blindness, heart disease, kidney damage, and stroke. Although the cure of DM has improved over the past decades, its morbidity and mortality rates remain high. Hence, new therapeutic strategies are needed to overcome the burden of this disease. One such prevention and treatment strategy that is easily accessible to diabetic patients at low cost is the use of medicinal plants, vitamins, and essential elements. The research objective of this review article is to study DM and explore its treatment modalities based on medicinal plants and vitamins. To achieve our objective, we searched scientific databases of ongoing trials in PubMed Central, Medline databases, and Google Scholar websites. We also searched databases on World Health Organization International Clinical Trials Registry Platform to collect relevant papers. Results of numerous scientific investigations revealed that phytochemicals present in medicinal plants (Allium sativum, Momordica charantia, Hibiscus sabdariffa L., and Zingiber officinale) possess anti-hypoglycemic activities and show promise for the prevention and/or control of DM. Results also revealed that intake of vitamins C, D, E, or their combination improves the health of diabetes patients by reducing blood glucose, inflammation, lipid peroxidation, and blood pressure levels. However, very limited studies have addressed the health benefits of medicinal plants and vitamins as chemo-therapeutic/preventive agents for the management of DM. This review paper aims at addressing this knowledge gap by studying DM and highlighting the biomedical significance of the most potent medicinal plants and vitamins with hypoglycemic properties that show a great potential to prevent and/or treat DM.

Green Alternatives as Antimicrobial Agents in Mitigating Periodontal Diseases: A Narrative Review

Periodontal diseases and dental caries are the most common infectious oral diseases impacting oral health globally. Oral cavity health is crucial for enhancing life quality since it serves as the entranceway to general health. The oral microbiome and oral infectious diseases are strongly correlated. Gram-negative anaerobic bacteria have been associated with periodontal diseases. Due to the shortcomings of several antimicrobial medications frequently applied in dentistry, the lack of resources in developing countries, the prevalence of oral inflammatory conditions, and the rise in bacterial antibiotic resistance, there is a need for reliable, efficient, and affordable alternative solutions for the prevention and treatment of periodontal diseases. Several accessible chemical agents can alter the oral microbiota, although these substances also have unfavorable symptoms such as vomiting, diarrhea, and tooth discoloration. Natural phytochemicals generated from plants that have historically been used as medicines are categorized as prospective alternatives due to the ongoing quest for substitute products. This review concentrated on phytochemicals or herbal extracts that impact periodontal diseases by decreasing the formation of dental biofilms and plaques, preventing the proliferation of oral pathogens, and inhibiting bacterial adhesion to surfaces. Investigations examining the effectiveness and safety of plant-based medicines have also been presented, including those conducted over the past decade.

Molecular mechanism of the anti-inflammatory effects of plant essential oils: A systematic review

ETHNOPHARMACOLOGICAL RELEVANCE

Plant essential oils (PEOs) extracted from aromatic compounds of the plant contain complex mixtures of volatile and lipophilic bioactive compounds. In ancient Egypt, Arabia, Greece, and China, PEOs were traditional used in aromatherapy for various health disorders, including pain and inflammation.

AIM OF THE STUDY

In this review, we provide an overview of the anti-inflammatory effects of PEOs and the underlying mechanisms associated with anti-inflammatory effects using in vitro and in vivo models. Further, clinical trials associated with PEOs were explored.

MATERIALS AND METHODS

The literature search was performed using various web-based tools and databases like Google Scholar, Web of Science, PubMed, CNKI and SCOPUS. The keywords used for conducting the literature review were general terms like "essential oils" followed by (AND) the subject of interest like "in vitro and/or in vivo anti-inflammatory models," "inflammatory response," "inflammatory indicators," "pro-inflammatory cytokines," "signaling pathway," "anti-inflammatory mechanism," "toxicology and side effects" and "clinical trials." The articles selected were published between 2017 and 2022. The articles prior to 2017 were only considered if they were associated with molecular mechanisms or signaling pathways involved in the inflammatory responses.

RESULTS

In vitro and in vivo inflammation models have been used to study the anti-inflammatory effects of 48 PEOs. Studies have reported that PEOs targets and inhibit multiple dysregulated signaling pathways associated with inflammation, including Toll-like receptors, nuclear transcription factor-κ B, mitogen-activated protein kinases, Nod-like receptor family pyrin domain containing 3, and auxiliary pathways like the nuclear factor erythroid 2-related factor 2/antioxidant response element and Janus kinase/signal transducers and activators of transcription) signaling pathways.

CONCLUSION

PEOs extracted from different plant materials had varied qualitative and quantitative compositions of biologically active compounds. Different anti-inflammatory potentials and different molecular signal transduction have been attributed to PEOs-derived bioactive compounds with different chemical structures. The data on therapeutic efficacy and the long-term side effects of PEOs as an anti-inflammatory drug are still unknown due to the lack of clinical trials on PEOs. There is still insufficient evidence to draw conclusions on anti-inflammatory properties of PEOs without promising outcomes from clinical trials.

Heliotropium ramosissimum metabolic profiling, in silico and in vitro evaluation with potent selective cytotoxicity against colorectal carcinoma

Heliotropium is a genus of the Boraginaceae family. Its members are used in many traditional and folklore medicines to treat several ailments. Despite this widespread usage, only a few evidence-based scientific studies investigated and identified its phytoconstituents. Herein, we documented the chemical profile of the Heliotropium ramosissimum methanolic extract using gas chromatography-mass spectrometry (GC–MS) and liquid chromatography-tandem mass spectrometry (LC–ESI–MS/MS) and assessed its antioxidant and cytotoxic effects. The methanolic extract exhibited high phenolic content (179.74 ± 0.58 µg/mL) and high flavonoid content (53.18 ± 0.60 µg/mL). The GC–MS analysis of the lipoidal matter allowed us to identify 41 compounds with high percentages of 1,2-benzenedicarboxylic acid, bis(2-methoxyethyl) ester (23.91%), and 6,10,14-trimethylpentadecan-2-one (18.74%). Thirty-two phytomolecules were tentatively identified from the methanolic extract of H. ramosissimum using LC–MS/MS. These compounds belonged to several phytochemical classes such as phenolic acids, alkaloids, coumarins, and flavonoids. Furthermore, we assessed the antioxidant activity of the methanolic extract by DPPH assay and oxygen radical absorbance capacity assay, which yielded IC₅₀ values of 414.30 µg/mL and 170.03 ± 44.40 µM TE/equivalent, respectively. We also assessed the cytotoxicity of the methanolic extract on seven different cell lines; Colo-205, A-375, HeLa, HepG-2, H-460, and OEC showed that it selectively killed cancer cells with particularly potent cytotoxicity against Colo-205 without affecting normal cells. Further studies revealed that the extract induced apoptosis and/or necrosis on Colo-205 cell line at an IC₅₀ of 18.60 µg/mL. Finally, we conducted molecular docking on the LC–ESI–MS/MS-identified compounds against colon cancer antigen 10 to find potentially cytotoxic compounds. Binding score energy analysis showed that isochlorogenic acid and orientin had the highest affinity for the colon cancer antigen 10 protein, with binding scores of (− 13.2001) and (− 13.5655) kcal/mol, respectively. These findings suggest that Heliotropium ramosissimum contains potent therapeutic candidates for colorectal cancer treatment.

GC-MS Profiling, Anti-Helicobacter pylori, and Anti-Inflammatory Activities of Three Apiaceous Fruits' Essential Oils

Eradication of Helicobacter pylori is a challenge due to rising antibiotic resistance and GIT-related disorders. Cuminum cyminum, Pimpinella anisum, and Carum carvi are fruits belonging to the Apiaceae family. Their essential oils were extracted, analyzed using GC-MS, tested for anti-H. pylori activity by a micro-well dilution technique, identified for potential anti-H. pylori inhibitors by an in-silico study, and investigated for anti-inflammatory activity using a COX-2 inhibition assay. Results showed that the main components of C. cyminum, P. anisum, and C. carvi were cumaldehyde (41.26%), anethole (92.41%), and carvone (51.38%), respectively. Essential oil of C. cyminum exhibited the greatest anti-H. pylori activity (3.9 µg/mL) followed by P. anisum (15.63 µg/mL), while C. carvi showed the lowest activity (62.5 µg/mL). The in-silico study showed that cumaldehyde in C. cyminum has the best fitting energy to inhibit H. pylori.C. cyminum essential oil showed the maximum ability to reduce the production of Cox-2 expression approaching celecoxib with IC₅₀ = 1.8 ± 0.41 µg/mL, followed by the C. carvi oil IC₅₀ = 7.3 ± 0.35 µg/mL and then oil of P. anisum IC₅₀ = 10.7±0.63 µg/mL. The investigated phytochemicals in this study can be used as potential adjunct therapies with conventional antibiotics against H. pylori.

The effect of roselle leaf (Hibiscus sabdariffa L.) extract gel on wound healing

Roselle (Hibiscus sabdariffa L.) belongs to the genus Hibiscus with proven anti-inflammatory, antioxidant, and antimicrobial properties. Scientific evidence associated roselle content with bioactive compounds, such as phenolic acids, flavonoids, and anthocyanin. Most studies focused on their petals, while research on leaf extract on wound healing has never been done. This study aimed to assess the effect of roselle leaf extract on wound healing in rats. This was an experimental laboratory study with a posttest-only control group design. There were 30 rats divided into 5 groups: negative control, 5%, 10%, and 15% roselle leaf extract, and positive control (bioplacenton). The parameters assessed in this research were wound size and histological assessment. The data were analyzed using ANOVA. P<0.05 was considered statistically significant. Wound healing percentage and epithelial thickness in the 15% group were the largest (84.17%; 64.69 µm). The lowest value was recorded in placebo (64%; 36.33 µm). Meanwhile, wound healing percentage and epithelial thickness of rats in the 5% and 10% groups were 68.53%, 43,57 µm, and 78.11%, 56.49 µm, respectively. Finally, positive control had a 77.44% wound healing percentage and 49.7 µm epithelial thickness. There were no significant differences in wound healing and epithelial thickness among the groups. Roselle leaf extract at 15% concentration showed greater wound healing properties based on clinical and histological assessment. Although there were no statistically significant differences, roselle leaf showed an opportunity to be further investigated as a potential wound healing therapy.

The Ameliorative Role of Hibiscetin against High-Fat Diets and Streptozotocin-Induced Diabetes in Rodents via Inhibiting Tumor Necrosis Factor-α, Interleukin-1β, and Malondialdehyde Level

Hibiscetin, as one of the main bioactive constituents of Hibiscus sabdariffa, has many pharmacological activities, but its antihyperglycemic activity has not been fully interpreted yet. The current research was developed from this perspective. The study intended to appraise the antidiabetic capability of hibiscetin in a high-fat diet (HFD) and streptozotocin (STZ; 50 mg/kg, intraperitoneally)-induced diabetes in an experimental animal. The efficiency of hibiscetin at 10 mg/kg in an “HFD/STZ model” remedy in rats with experimentally caused diabetes was explored for 42 days. The efficacy of hibiscetin was observed on several diabetes parameters. The average body weight and an array of biochemical markers were determined, including blood glucose, insulin, total protein (TP), lipid profile, aspartate aminotransferase (AST), alanine aminotransferase (ALT), IL-6, IL-1β, tumor necrosis factor-α (TNF-α), adiponectin, leptin, resistin, malondialdehyde (MDA), catalase (CAT), glutathione (GSH), and superoxide dismutase (SOD). The antidiabetic benefits of hibiscetin were proven by a substantial reduction in blood glucose, lipid profile (TC and TG), total protein, IL-6, IL-1β, MDA, TNF-α, leptin, adiponectin, ALT, and AST in the therapy group compared to the diabetic disease standard. Furthermore, hibiscetin therapy also reversed the lowered levels of insulin, resistin, GSH, SOD, and CAT in diabetic rats. It was determined that hibiscetin may be beneficial in terms of reducing diabetes problems due to its effects on both oxidative stress and inflammation and that more research for this design should be conducted.

Two new isoquinolines from Corydalis saxicola

Two new isoquinolines (1 and 3), along with 4 known isoquinolines were obtained from the ethanol extract of Corydalis saxicola Bunting. Their structures were elucidated based on detailed spectroscopic data (NMR, HR-ESIMS) and comparison with literature data. The absolute configurations of the new compounds were assigned by comparing computed electronic circular dichroism (ECD). The anti-inflammatory effects of the isolates were assessed by inhibiting NO production in LPS-induced RAW264.7 macrophage cells, and the results showed that compounds 1-6 exhibited anti-inflammatory activities, with IC₅₀ values ranged from 44.24 ± 1.16 to 69.00 ± 5.41 µM.

Cinnamon and Eucalyptus Oils Suppress the Inflammation Induced by Lipopolysaccharide In Vivo

Inflammation caused by bacterial lipopolysaccharide (LPS) disrupts epithelial homeostasis and threatens both human and animal health. Therefore, the discovery and development of new anti-inflammatory drugs is urgently required. Plant-derived essential oils (EOs) have good antioxidant and anti-inflammatory activities. Thus, this study aims to screen and evaluate the effects of cinnamon oil and eucalyptus oil on anti-inflammatory activities. The associated evaluation indicators include body weight gain, visceral edema coefficient, superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), malondialdehyde (MDA), nitrogen monoxide (NO), interleukin-6 (IL-6), interleukin-10 (IL-10), tumor necrosis factor alpha (TNF-α), Urea, Crea, ALT, TLR4, MyD88, NF-κB, IκB-α, iNOS, and Mn-SOD. In addition, tissue injury was determined by H&E staining. The results revealed that cinnamon oil and eucalyptus oil suppressed inflammation by decreasing SOD, TNF-α, and NF-κB levels. We also found that cinnamon oil increased the level of GSH-Px, MDA, and Mn-SOD, as well as the visceral edema coefficient of the kidney and liver. Altogether, these findings illustrated that cinnamon oil and eucalyptus oil exhibited wide antioxidant and anti-inflammatory activities against LPS-induced inflammation.

Trigonella foenum-graecum Seeds Oil Attenuated Inflammation and Angiogenesis in vivo through Down-Regulation of TNF-α

INTRODUCTION

Inflammation is a vital reaction of the natural immune system that protects against encroaching agents. However, uncontrolled inflammation can lead to complications. Trigonella foenumgraecum is traditionally used as an anti-inflammatory herb.

OBJECTIVES

The current study was conducted to explore the antioxidant, anti-inflammatory, and antiangiogenic potentials of Trigonella foenum-graecum seeds oil.

METHODS

Oil was extracted from seeds of Trigonella foenum-graecum by cold press method and labelled as TgSO. Phytochemical (GC-MS, Folin-Ciocalteu method) and metal analyses were conducted to evaluate the metalo-chemical profile of TgSO. In vitro antioxidant assays (2,2-diphenyl-1-picrylhydrazyl, 2,2'-azino-bis-3- ethylbenzothiazoline-6-sulfonic acid and ferric reducing antioxidant power) were performed to assess its antioxidant potential. In vitro antimicrobial activity was evaluated using agar disc diffusion method and the safety profile of TgSO was assessed in acute toxicological studies following OECD 425 guidelines. In vivo antiinflammatory activities of TgSO were assessed in carrageenan, serotonin, histamine, formalin, and cotton pelletinduced oedema models. Serum TNF-α, Superoxide Dismutase (SOD) and, Catalases (CAT) levels were assessed by ELISA kits. In vivo antiangiogenic activity of TgSO was screened in chick Chorioallantoic Membrane (CAM) assay. Histopathological studies using excised paws were conducted to observe the effects of TgSO treatment at the tissue level. In silico docking studies were conducted to screen the binding potentials of identified compounds with TNF-α.

RESULTS

Extraction by cold press method yielded 16% of TgSO. Phytochemical analysis of TgSO through GCMS showed the presence of eugenol, dihydrocoumairn, heptadecanoic acid, tri- and tetradecanoic acid, and hexadecanoic acid, respectively. Total phenolic contents of TgSO were found to be 0.30±0.01mg/g gallic acid equivalent in Folin-Ciocalteu method. Metal analysis indicated the presence of different metals in TgSO. Findings of antioxidant models showed the moderate antioxidant potential of TgSO. Findings of antimicrobial assays showed that TgSO was active against bacterial (S. aureus, S. epidermidis) and fungal (C. albicans, and A. niger) strains. In vivo toxicity study data showed that TgSO was safe up to the dose of 5000 mg/kg. Data of oedema models showed a significant (p<0.05) reduction in oedema development in TgSO treated animals in both acute and chronic models. Histopathological evaluations of paws showed minimum tissue infiltration with inflammatory cells in TgSO-treated animals. Treatment with TgSO also significantly (p<0.05) down-regulated TNF-α in serum while levels of SOD and CAT were up-regulated. Findings of the CAM assay revealed the antiangiogenic activity of TgSO. Findings of in silico docking studies showed that identified phytoconstituents can bind with culprit cytokine (TNF-α).

CONCLUSION

Data obtained from the current study conclude that TgSO has antioxidant, anti-inflammatory, and antiangiogenic effects that validate its traditional uses. Synergistic actions of different phytoconstituents are proposed to be responsible for the observed effects.

Immunomodulatory and Mechanistic Considerations of Hibiscus sabdariffa (HS) in Dysfunctional Immune Responses: A Systematic Review

Hibiscus sabdariffa calyx (HS) water decoction extract is a commonly consumed beverage with various pharmacological properties. This systematic review examines the possible effect of HS intake on immune mediators. The Scopus and PUBMED databases were searched for all human and animal studies that investigated the effect of HS administration on immune related biomarkers. For each of the immune biomarkers, the mean, standard deviation and number of subjects were extracted for both the HS treated and untreated group. These values were used in the computation of standardized mean difference (SMD). Statistical analysis and forest plot were done with R statistical software (version 3.6.1). Twenty seven (27) studies met the eligibility criteria. Twenty two (22) of the studies were used for the meta-analysis which included a total of 1211 subjects. The meta-analysis showed that HS administration significantly lowered the levels of TNF-α (n=10; pooled SMD: -1.55; 95% CI: -2.43, -0.67; P < 0.01), IL-6 (n=11; pooled SMD:-1.09; 95% CI: -1.77, -0.40; P < 0.01), IL-1β (n=7; pooled SMD:-0.62; 95% CI: -1.25, 0.00; P = 0.05), Edema formation (n=4; pooled SMD: -2.29; 95% CI: -4.47, -0.11; P = 0.04), Monocyte Chemoattractant Protein -1 (n=4; pooled SMD: -1.17; 95% CI: -1.78, -0.57; P < 0.01) and Angiotensin converting enzyme cascade (n=6; pooled SMD: -0.91; 95% CI: -1.57, -0.25; P < 0.01). The levels of IL-10 (n=4; pooled SMD: -0.38; 95% CI: -1.67, 0.91; P = 0.56), Interleukin 8 (n=2; pooled SMD:-0.12; 95% CI: -0.76, 0.51; P = 0.71), iNOS (n=2; pooled SMD:-0.69; 95% CI: -1.60, 0.23 P = 0.14) and C- Reactive Protein (n=4; pooled SMD: 0.05; 95% CI: -0.26, 0.36; P = 0.75), were not significantly changed by HS administration. Some of the results had high statistical heterogeneity. HS may be promising in the management of disorders involving hyperactive immune system or chronic inflammation.

Chemical Profile and Phytotoxic Action of Hibiscus trionum Essential Oil

The chemical profile and phytotoxic action of Hibiscus trionum essential oil (EO) was studied. In total 17 compounds were identified via GC/MS, representing 94.18 % of the entire oil, with phytol (40.37 %) being the dominant constituent. Bioassay revealed that the EO inhibited root elongation of Medicago sativa and Amaranthus retroflexus by 32.66 % and 61.86 % at 5 mg/mL, respectively; meanwhile, the major component phytol also exhibited significant phytotoxic activity, suppressing radical elongation of Pennisetum alopecuroides, M. sativa and A. retroflexus by 26.08 %, 27.55 % and 43.96 % at 1 mg/mL, respectively. The fact that the EO showed weaker activity than phytol implied that some constituents might trigger antagonistic action to decrease the oil's activity. Our study is the first on the chemical profile and phytotoxic effect of H. trionum EO.

Hofmeister Effect-Assistant Fabrication of All-Natural Protein-based Porous Materials Templated from Pickering Emulsions

Porous materials derived from natural and biodegradable polymers have received growing interest. We demonstrate here an attractive method for the preparation of protein-based porous materials using emulsions stabilized by gliadin-chitosan hybrid particles (GCHPs) as the template, with the addition of gelatin and kosmotropic ions to improve the mechanical strength. The microstructure, mechanical properties, cytotoxicity, and fluid absorption behavior of porous materials were systematically investigated. This strategy facilitated the formation of porous materials with highly open and interconnected pore structure, which can be manipulated by altering the mass ratio of hexane or gelatin in the matrix. The Hofmeister effect resulted from kosmotropic ions greatly enhanced the Young's modulus and the compressive stress at 40% strain of porous materials from 0.56 to 6.84 MPa and 0.26 to 1.11 MPa, respectively. The developed all-natural porous materials were nontoxic to HaCaT cells; they also had excellent liquid (i.e., simulated body fluid and rabbit blood) absorption performance and advantages in resisting stress and maintaining geometry shape. The effects of different concentration amounts and type of salts in the Hofmeister series on the formation and performance of porous materials were also explored. Mechanical strength of porous materials was gradually enhanced when the (NH₄)₂SO₄ concentration increased from 0 to 35 wt %, and the other four kosmotropic salts, including Na₂S₂O₃, Na₂CO₃, NaH₂PO₄, and Na₂SO₄, also showed positive effects. This work opens a simple and feasible way to produce nontoxic and biodegradable porous materials with favorable mechanical strength and controllable pore structure. These materials have broad potential application in many fields involving biomedical and material science, such as cell culture, (bio)catalysis, and wound or bone defect healing.

The Impact of Herbal Infusion Consumption on Oxidative Stress and Cancer: The Good, the Bad, the Misunderstood

The release of reactive oxygen species (ROS) and oxidative stress is associated with the development of many ailments, including cardiovascular diseases, diabetes and cancer. The causal link between oxidative stress and cancer is well established and antioxidants are suggested as a protective mechanism against cancer development. Recently, an increase in the consumption of antioxidant supplements was observed globally. The main sources of these antioxidants include fruits, vegetables, and beverage. Herbal infusions are highly popular beverages consumed daily for different reasons. Studies showed the potent antioxidant effects of plants used in the preparation of some herbal infusions. Such herbal infusions represent an important source of antioxidants and can be used as a dietary protection against cancer. However, uncontrolled consumption of herbal infusions may cause toxicity and reduced antioxidant activity. In this review, eleven widely consumed herbal infusions were evaluated for their antioxidant capacities, anticancer potential and possible toxicity. These herbal infusions are highly popular and consumed as daily drinks in different countries. Studies discussed in this review will provide a solid ground for researchers to have better understanding of the use of herbal infusions to reduce oxidative stress and as protective supplements against cancer development.

3,4-seco-Dammarane Triterpenoid Saponins with Anti-Inflammatory Activity Isolated from the Leaves of Cyclocarya paliurus

Cyclocarya paliurus is commonly used for the prevention and treatment of hypertension, diabetes, and inflammation in South China. Although research on the anti-inflammatory effects of C. paliurus leaves has been reported, no active anti-inflammatory compounds have been identified. In the present study, RAW 264.7 cells were used to establish a bioactivity-guided identification model to verify the inhibitory effects of C. paliurus leaves on inflammation and identify the anti-inflammatory constituents. The active fraction was isolated to yield 18 dammarane triterpenoid saponins, including 11 new 3,4-seco-dammarane triterpenoid saponins (1-11), the structures of which were identified on the basis of analyses of nuclear magnetic resonance (NMR) spectroscopy and mass spectrometry (MS) and comparison with literature data. Compounds 7, 8, 10, and 11 showed strong inhibition on nitric oxide (NO) productions, with IC50 values ranging from 8.23 to 11.23 μM. These four compounds significantly decreased the secretion of tumor necrosis factor-alpha (TNF-α), prostaglandin E2 (PGE2), and interleukin 6 (IL-6) in lipopolysaccharide-activated RAW 264.7 cells. Furthermore, compound 7 decreased the expression of the proteins cyclooxygenase-2 (COX-2), inducible nitric-oxide synthase (iNOS), and nuclear factor kappa-B (NF-κB/p65). In addition, the structure-activity relationships of the isolates were investigated. The results suggest that 3,4-seco-dammarane triterpenoid saponins may be used as potential anti-inflammatory drugs and warrant further investigation.

Pleiotropic Biological Effects of Dietary Phenolic Compounds and their Metabolites on Energy Metabolism, Inflammation and Aging

Dietary phenolic compounds are considered as bioactive compounds that have effects in different chronic disorders related to oxidative stress, inflammation process, or aging. These compounds, coming from a wide range of natural sources, have shown a pleiotropic behavior on key proteins that act as regulators. In this sense, this review aims to compile information on the effect exerted by the phenolic compounds and their metabolites on the main metabolic pathways involved in energy metabolism, inflammatory response, aging and their relationship with the biological properties reported in high prevalence chronic diseases. Numerous in vitro and in vivo studies have demonstrated their pleiotropic molecular mechanisms of action and these findings raise the possibility that phenolic compounds have a wide variety of roles in different targets.

Essential oil from halophyte Lobularia maritima: protective effects against CCl4-induced hepatic oxidative damage in rats and inhibition of the production of proinflammatory gene expression by lipopolysaccharide-stimulated RAW 264.7 macrophages

The present study evaluates the chemical profiling of the essential oil of a halophyte, L. maritima (LmEO), and its protective potential against CCl4-induced oxidative stress in rats. Forty compounds have been identified in LmEO. The major components are α-pinene (3.51%), benzyl alcohol (8.65%), linalool (22.43%), pulegone (3.33%), 1-phenyl butanone (7.33%), globulol (4.32%), γ-terpinene (6.15%), terpinen-4-ol (4.31%), α-terpineol (3.9%), ledol (3.59%), epi-α-cadinol (3.05%) and α-cadinol (4.91%). In comparison with the CCl4-intoxicated group, LmEO treatment resulted in decreased liver serum marker enzymes, decreased lipid peroxidation and increased antioxidant enzyme levels, with overall further amelioration of oxidative stress. The administration of LmEO to CCl4-treated rats at a dose of 250 mg kg-1 body weight significantly reduced the toxic effects and the oxidative stress on the liver, thus validating the traditional medicinal claim of this plant. Moreover, the anti-inflammatory activity of LmEO was evaluated in lipopolysaccharide-stimulated murine RAW 264.7 cells. Our oil could modulate the inflammatory mode of the macrophages by causing reduction in iNOS and COX2 enzymes as well as in IL-1β, IL-6, and TNF-α cytokine levels. These findings suggest that LmEO exerts anti-inflammatory effects by regulating the expression of inflammatory cytokines.

Chemistry and immunostimulatory activity of a polysaccharide from Undaria pinnatifida

An immunologically active polysaccharide named as UPP-2 (1035.52 kDa) was isolated from Undaria pinnatifida using traditional water extraction followed by DEAE Sepharose fast flow chromatography. UPP-2 was proven to be a low sulfated polysaccharide with relatively abundant uronic acid (13.08 ± 0.67%). UPP-2 mainly consisted of xylose (64.55%), glucose (23.81%), arabinose (5.90%) and mannose (4.26%), and its main glycosidic linkage types included →2)-α-D-Xylp-(1→, →4)-α-D-Glcp-(1→, α-D-Xylp-(1→ and →2,4)-β-D-Xylp-(1 → . Results indicated that UPP-2 significantly promoted the proliferation and pinocytic capacity of RAW264.7 cells, and upregulated the mRNA expressions of iNOS, TNF-α, IL-6 and IL-1β at 100-600 μg/mL with a maximum of 195, 42, 768 and 539 times of those of the negative control, respectively. Moreover, UPP-2 significantly increased the secretions of nitric oxide, TNF-α and IL-6 at 100-600 μg/mL (8.0, 73.1 and 188.7 times compared to those of the negative control, respectively), as well as promoted the production of IL-1β obviously at 600 μg/mL. Overall, UPP-2 could be served as a potential dietary supplement or functional food based on its immunostimulatory activity.

Potential anti-inflammatory and antioxidant effects of Citrus aurantium essential oil against carbon tetrachloride-mediated hepatotoxicity: A biochemical, molecular and histopathological changes in adult rats

The present study aimed (1) to investigate the chemical composition as well as the anti-inflammatory properties and in vitro antioxidant activity of Citrus aurantium peel essential oil (pEOCa) and (2) to evaluate its potential effect in vivo. The main results showed that the major components of pEOCa are Limonene and Linalool. Additionally, DPPH scavenging ability and β-carotene bleaching inhibition tests confirmed the antioxidant capacity of pEOCa. Our oil reduced the production of NO by LPS-stimulated RAW264,7 macrophages in a concentration-dependent. This inhibition occurred at a transcriptional level. pEOCa in CCl₄ treated rats alleviated hepatotoxicity as monitored by the improvement of hepatic oxidative stress biomarkers levels plasma biochemical parameters, and DNA molecule aspect. Furthermore, the mRNA gene expression of Cu-Zn SOD, CAT, and GPx increased under CCl₄ + pEOCa exposure to reach the same value to the control. Similarly, antioxidant activities of these three enzymes changed in accordance with the mRNA levels. These results were confirmed by the histological results. It seems obvious that the treatment with pEOCa prevented liver damage induced by CCl₄ , thus preventing the harmful effects of free radicals.

Essential Oils and Their Major Compounds in the Treatment of Chronic Inflammation: A Review of Antioxidant Potential in Preclinical Studies and Molecular Mechanisms

Inflammatory diseases result from the body's response to tissue damage, and if the resolution is not adequate or the stimulus persists, there will be progression from acute inflammation to chronic inflammation, leading to the development of cancer and neurodegenerative and autoimmune diseases. Due to the complexity of events that occur in inflammation associated with the adverse effects of drugs used in clinical practice, it is necessary to search for new biologically active compounds with anti-inflammatory activity. Among natural products, essential oils (EOs) present promising results in preclinical studies, with action in the main mechanisms involved in the pathology of inflammation. The present systematic review summarizes the pharmacological effects of EOs and their compounds in in vitro and in vivo models for inflammation. The research was conducted in the following databases: PubMed, Scopus, BIREME, Scielo, Open Grey, and Science Direct. Based on the inclusion criteria, 30 articles were selected and discussed in this review. The studies listed revealed a potential activity of EOs and their compounds for the treatment of inflammatory diseases, especially in chronic inflammatory conditions, with the main mechanism involving reduction of reactive oxygen and nitrogen species associated with an elevation of antioxidant enzymes as well as the reduction of the nuclear factor kappa B (NF-κB), reducing the expression of proinflammatory cytokines. Thus, this review suggests that EOs and their major compounds are promising tools for the treatment of chronic inflammation.

Dingchuan tang essential oil inhibits the production of inflammatory mediators via suppressing the IRAK/NF-κB, IRAK/AP-1, and TBK1/IRF3 pathways in lipopolysaccharide-stimulated RAW264.7 cells

Background

Dingchuan tang (asthma-relieving decoction), a formula of nine herbs, has been used for treating respiratory inflammatory diseases for >400 years in the People’s Republic of China. However, the mechanisms underlying the anti-inflammatory action of dingchuan tang is not fully understood. This study aims to investigate the effects of Dingchuan tang essential oil (DCEO) on inflammatory mediators and the underlying mechanism of action.

Materials and methods

DCEO was extracted by steam distillation. Lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages were used as the cell model. Production of nitric oxide (NO) was determined by the Griess test. Protein secretion and mRNA levels of inflammatory mediators were measured by the enzyme-linked immunosorbent assay (ELISA) and quantitative real-time polymerase chain reaction (qRT-PCR), respectively. Protein levels were examined by Western blot. Nuclear localization of nuclear factor-kappa B (NF-κB) was detected using immunofluorescence analyses.

Results

DCEO significantly reduced LPS-triggered production of NO and prostaglandin E2 (PGE2) and decreased protein and mRNA levels of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2). LPS induced upregulation of protein and mRNA levels of cytokines (interleukin-1β [IL-1β], interleukin-6 [IL-6], tumor necrosis factor-α [TNF-α]), and chemokines (monocyte chemoattractant protein-1 [MCP-1], chemokine [C-C motif] ligand 5 [CCL-5], and macrophage inflammatory protein [MIP]-1α) were suppressed by DCEO treatment. Phosphorylation and nuclear protein levels of transcription factors (activator protein-1 [AP-1], NF-κB, interferon regulatory factor 3 [IRF3]) were decreased by DCEO. Protein levels of phosphorylated IκB-α, IκB kinase α/β (IKKα/β), phosphatidylinositol 3-kinase (PI3K), protein kinase B (Akt), TGF β-activated kinase 1 (TAK1), TANK-binding kinase 1 (TBK1), extracellular signal-regulated kinase (ERK), p38 mitogen-activated protein kinase (p38), and c-Jun N-terminal kinase (JNK) were lowered by DCEO. Moreover, degradation of interleukin-1 receptor-associated kinase 1 (IRAK1) and IRAK4 induced by LPS was inhibited by DCEO treatment.

Conclusion

Suppression of the interleukin-1 receptor-associated kinase (IRAK)/NF-κB, IRAK/AP-1 and TBK1/IRF3 pathways was associated with the inhibitory effects of DCEO on inflammatory mediators in LPS-stimulated RAW264.7 macrophages. This study provides a pharmacological justification for the use of dingchuan tang in managing inflammatory disorders.

Enhancement of Anti-Inflammatory Properties of Nobiletin in Macrophages by a Nano-Emulsion Preparation

Lots of active substances are hydrophobic materials at ambient and body temperatures, decreasing their bioavailability and posing great challenges to successful incorporation into medication and functional foods. The goal of this research was to develop a nanoemulsion delivery system containing a hydrophobic crystalline bioactive component (nobiletin) to improve the anti-inflammatory activity. Nobiletin was incorporated into the oily phase, and the nanoemulsions were fabricated using high-speed and high-pressure homogenization. Particle size, polydispersity index (PDI), and zeta potential were evaluated by a commercial laser light scattering instrument. The anti-inflammatory activities were performed in LPS-stimulated RAW 264.7 cells. The developed nobiletin nanoemulsion had an average droplet size of 168.6 ± 3.8 nm and a PDI of 0.168, while the average diameter of the blank nanoemulsion was 157.3 ± 1.9 nm and its PDI was 0.161. The zeta potential values of nobiletin nanoemulsion and blank nanoemulsion were -68.45 ± 0.64 and -62.75 ± 0.21 mV, respectively. All obtained nanoemulsions kept physically stable during storage at 4, 25, and 37 °C. A nobiletin-loaded nanoemulsion showed an enhanced anti-inflammatory activity in LPS-induced macrophages, with a decrease in pro-inflammatory mediators and cytokines. The findings suggested that the nanoemulsion would be used as an effective delivery system for nobiletin to improve its anti-inflammatory activity.

Polyphenols from Blossoms of Citrus aurantium L. var. amara Engl. Show Significant Anti-Complement and Anti-Inflammatory Effects

Citrus aurantium L. var. amara Engl. (CAVA) was traditionally used as a digestant or expectorant in China. Crude polyphenols (CAVAP-W) extracted from blossoms of CAVA were mainly composed of eriocitrin/neoeriocitrin, eriocitrin/neoeriocitrin, rhoifolin, hesperidin, naringin, rutin, veronicastroside, neohesperidin, and hesperetin by LC-MS analysis. CAVAP-W showed significant anticomplement and anti-inflammatory effects. Due to the close relationship between anticomplement and anti-inflammatory activity, the anti-inflammatory effect was further investigated and the results showed that CAVAP-W significantly suppressed production of interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), interleukin-1beta (IL-1β), and mRNA expression of inducible nitric oxide synthase (iNOS), IL-6, TNF-α, IL-1β, and cyclooxygenase-2 (COX-2) in lipopolysaccharides-stimulated RAW264.7 cells. Furthermore, CAVAP-W inhibited mitogen-activated protein kinase (MAPK) phosphorylation and NF-κB activation through suppressing nuclear translocation of nuclear factor-kappa B (NF-κB) P65, degradation and phosphorylation of IκBα, phosphorylation of IκKα/ß, c-Jun N-terminal kinase (JNK), and P38, and activation of COX-2, thereby exerting the anti-inflammatory effects.

Anti-inflammatory Effect of Essential Oil from Citrus aurantium L. var. amara Engl

Essential oil has been popularly used as an alternative for the treatment of inflammation. The bioactivities of essential oil from blossoms of Citrus aurantium L. var. amara Engl (CAVAO) showed greater anti-inflammation potential than that of antioxidant, anticancer, and 3T3-L1 proliferation inhibition. CAVAO (250 μg/mL) significantly inhibited production of nitric oxide (NO) (99.54 ± 2.81%), interleukin-6 (IL-6) (98.11 ± 1.62%), tumor necrosis factor-α (TNF-α) (41.84 ± 1.52%), and interleukin-1β (IL-1β) (56.09 ± 2.21%) as well as their gene expression level. CAVAO also markedly decreased the expression levels of cyclooxygenase-2 (COX-2) gene and protein. Furthermore, CAVAO inhibited nuclear factor-κB (NF-κB) activation, which was justified by the inhibitory effect on NF-κB nuclear translocation, IκBα phosphorylation and degradation, and phosphorylation-dependent IκB kinase activation in RAW264.7 cells stimulated with lipopolysaccharides. CAVAO also suppressed the phosphorylation of c-Jun N-terminal kinase (JNK) and p38, indicating that mitogen-activated protein kinase (MAPK) signaling pathways were also blocked. The major constituents of CAVAO were characterized as linalool (64.6 ± 0.04%), α-terpineol (7.61 ± 0.03%), (R)-limonene (6.15 ± 0.04%), and linalyl acetate (5.02 ± 0.03%), which might be responsible for its observed anti-inflammation activity. It is concluded that CAVAO has great potential to be developed into a functional food for the treatment of inflammatory-associated diseases.

Determination of Volatile Flavour Profiles of Citrus spp. Fruits by SDE-GC-MS and Enantiomeric Composition of Chiral Compounds by MDGC-MS

INTRODUCTION

Citrus fruits are known to have characteristic enantiomeric key compounds biosynthesised by highly stereoselective enzymatic mechanisms. In the past, evaluation of the enantiomeric ratios of chiral compounds in fruits has been applied as an effective indicator of adulteration by the addition of synthetic compounds or natural components of different botanical origin.

OBJECTIVE

To analyse the volatile flavour compounds of Citrus junos Sieb. ex Tanaka (yuzu), Citrus limon BURM. f. (lemon) and Citrus aurantifolia Christm. Swingle (lime), and determine the enantiomeric ratios of their chiral compounds for discrimination and authentication of extracted oils.

METHODOLOGY

Volatile flavour compounds of the fruits of the three Citrus species were extracted by simultaneous distillation extraction and analysed by gas chromatography-mass spectrometry. The enantiomeric composition (ee%) of chiral camphene, sabinene, limonene and β-phellandrene was analysed by heart-cutting multidimensional gas chromatography-mass spectrometry.

RESULTS

Sixty-seven (C. junos), 77 (C. limon) and 110 (C. aurantifolia) volatile compounds were identified with limonene, γ-terpinene and linalool as the major compounds. Stereochemical analysis (ee%) revealed 1S,4R-(-) camphene (94.74, 98.67, 98.82), R-(+)-limonene (90.53, 92.97, 99.85) and S-(+)-β-phellandrene (98.69, 97.15, 92.13) in oil samples from all three species; R-(+)-sabinene (88.08) in C. junos; and S-(-)-sabinene (81.99, 79.74) in C. limon and C. aurantifolia, respectively.

CONCLUSION

The enantiomeric composition and excess ratios of the chiral compounds could be used as reliable indicators of genuineness and quality assurance of the oils derived from the Citrus fruit species. Copyright © 2017 John Wiley & Sons, Ltd.

Various Antioxidant Effects Were Attributed to Different Components in the Dried Blossoms of Citrus aurantium L. var. amara Engl

Citrus aurantium L. var. amara Engl. (CAVA) was traditionally used as an edible and medicinal material in China. Total flavonoids (CAVAF), alkaloids (CAVAA), polysaccharides (CAVAP), coumarins (CAVAC), and neroli (CAVAO) were extracted from CAVA. Hesperidin, naringin, and neohesperidin composed 83.94% of CAVAF, and synephrine represented 50.56% of CAVAA. On the basis of 1,1-diphenyl-2-picrylhydrazyl radical (DPPH^•), 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt radical cation (ABTS^• +), hydroxyl radical (^•OH), ferric-reducing antioxidant power (FRAP), and reducing power assays, the antioxidant activities of five components were comprehensively and comparatively investigated. CAVAF had a stronger DPPH^• scavenging effect and FRAP and reducing power. CAVAP and CAVAA exhibited comparable ^•OH scavenging effects to vitamin C. CAVAA showed the highest ABTS^• + scavenging activity. In conclusion, different constituents varied significantly toward different sources of free radicals and other oxidants. It is obvious that CAVA has various antioxidant effects, which are attributed to different components.

Extraction of antioxidant and antiproliferative ingredients from fruits of Rubus chingii Hu by active tracking guidance

Rubus chingii Hu, namely "Fu-pen-zi" in Chinese, has been used as a functional food in China for a long time. This study aims to identify its bioactive constituents with antioxidant and anti-tumor properties. R. chingii was extracted with 95% ethanol and then partitioned into four fractions: petroleum ether fraction, ethyl acetate fraction, n-butanol fraction, and water fraction. Results showed that the ethyl acetate fraction had the strongest antioxidant activity and cytotoxicity against human cancer cell lines (HepG-2, Bel-7402, A549 and MCF-7). Therefore, four compounds were isolated from the ethyl acetate fraction, and they were identified as ent-16α,17-dihydroxy-kauran-19-oic acid, tormentic acid, oleanolic acid and β-daucosterol, the first two of which were isolated and identified from R. chingii for the first time. In particular, tormentic acid exhibited excellent cytotoxicity activities against human tumor cell lines. The results obtained in this work might contribute to the understanding of biological activities of R. chingii and further investigation on its potential application is valued for food and drugs.

Immune enhancement effects and extraction optimization of polysaccharides from Citrus aurantium L. var. amara Engl

The crude polysaccharides ofCitrus aurantiumL. var.amaraEngl (CAVAPs) were extracted and their bioactivities including DPPH radical scavenging activity, cytotoxicity to human breast cancer cells, MCF-7, as well as lung cancer cells, HCC827, and their immune-enhancement activity were evaluated.