Anti-inflammatory activity of Cymbopogon citratus leaves infusion via proteasome and nuclear factor-κB pathway inhibition: contribution of chlorogenic acid

Effect of black mulberry (Morus nigra) extract treatment on cognitive impairment and oxidative stress status of D-galactose-induced aging mice

CONTEXT

Morus nigra L. (Moraceae) has various uses in traditional medicine. However, the effect of M. nigra on cognitive impairment has not been investigated yet.

OBJECTIVE

The objective of this study is to determine the phenolic acid content and DNA damage protection potential of M. nigra leaf extract and to investigate the extract effect on cognitive impairment and oxidative stress in aging mice.

MATERIALS AND METHODS

Phenolic acid content was determined by quantitative chromatographic analysis. DNA damage protection potential was evaluated on pBR322 plasmid DNA. Thirty-two Balb-C mice were randomly divided into four groups (control, d-galactose, d-galactose + M. nigra 50, and d-galactose + M. nigra 100). Mice were administered d-galactose (100 mg/kg, subcutaneous) and M. nigra (50 or 100 mg/kg, orally) daily for 8 weeks. Behavioral responses were evaluated with Morris water maze. Activities of antioxidant enzymes and levels of malondialdehyde (MDA) were assayed in serum, brain, and liver.

RESULTS

In extract, vanillic (632.093 μg/g) and chlorogenic acids (555.0 μg/g) were determined. The extract between 0.02 and 0.05 mg/mL effectively protected all DNA bands against the hazardous effect of UV and H2O2. Morus nigra significantly improved learning dysfunctions (p < 0.01), increased memory retention (p < 0.01), reduced MDA levels (p < 0.05), and elevated SOD, GPx, and CAT activities (p < 0.05) compared with the d-galactose group.

DISCUSSION AND CONCLUSION

These results show that M. nigra has the potential in improving cognitive deficits in mice and that M. nigra may be useful to suppress aging, partially due to its scavenging activity of free radicals and high antioxidant capacity.

Preventive and therapeutic effects of blueberry (Vaccinium corymbosum) extract against DSS-induced ulcerative colitis by regulation of antioxidant and inflammatory mediators

Inflammatory bowel disease (IBD) is an inflammatory disorder caused by hyperactivation of effector immune cells that produce high levels of proinflammatory cytokines. The aims of our study were to determine whether orally administered blueberry extract (BE) could attenuate or prevent the development of experimental colitis in mice and to elucidate the mechanism of action. Female Balb/C mice (n=7) were randomized into groups differing in treatment conditions (prevention and treatment) and dose of BE (50 mg/kg body weight). Acute ulcerative colitis was induced by oral administration of 3% dextran sodium sulfate for 7 days in drinking water. Colonic mucosal injury was assessed by clinical, macroscopic, biochemical and histopathological examinations. BE significantly decreased disease activity index and improved the macroscopic and histological score of colons when compared to the colitis group (P<.05). BE markedly attenuated myeloperoxidase accumulation (colitis group 54.97±2.78 nmol/mg, treatment group 30.78±1.33 nmol/mg) and malondialdehyde in colon and prostaglandin E2 level in serum while increasing the levels of superoxide dismutase and catalase (colitis group 11.94±1.16 U/ml, BE treatment group 16.49±0.39 U/ml) compared with the colitis group (P<.05). mRNA levels of the cyclooxygenase (COX)-2, interferon-γ, interleukin (IL)-1β and inducible nitric oxide synthase cytokines were determined by reverse transcriptase polymerase chain reaction. Immunohistochemical analysis showed that BE attenuates the expression of COX-2 and IL-1β in colonic tissue. Moreover, BE reduced the nuclear translocation of nuclear transcription factor kappa B (NF-κB) by immunofluorescence analysis. Thus, the anti-inflammatory effect of BE at colorectal sites is a result of a number of mechanisms: antioxidation, down-regulation of the expression of inflammatory mediators and inhibition of the nuclear translocation of NF-κB.

Cymbopogon citratus industrial waste as a potential source of bioactive compounds

BACKGROUND

Cymbopogon citratus (Cc), commonly known as lemongrass, is a very important crop worldwide, being grown in tropical countries. It is widely used in the food, pharmaceutical, cosmetic and perfumery industries for its essential oil. Cc aqueous extracts are also used in traditional medicine. They contain high levels of polyphenols, which are known for their antioxidant and anti-inflammatory properties. Hydrodistillation of lemongrass essential oil produces an aqueous waste (CcHD) which is discarded. Therefore a comparative study between CcHD and Cc infusion (CcI) was performed to characterize its phytochemical profile and to research its antioxidant and anti-inflammatory potential.

RESULTS

HPLC-PDA/ESI-MS(n) analysis showed that CcI and CcHD have similar phenolic profiles, with CcHD presenting a higher amount of polyphenols. Additionally, both CcI and CcHD showed antioxidant activity against DPPH (EC50 of 41.72 ± 0.05 and 42.29 ± 0.05 µg mL(-1) respectively) and strong anti-inflammatory properties, by reducing NO production and iNOS expression in macrophages and through their NO-scavenging activity, in a dose-dependent manner. Furthermore, no cytotoxicity was observed.

CONCLUSION

The data of this study encourage considering the aqueous solution from Cc leaf hydrodistillation as a source of bioactive compounds, which may add great industrial value to this crop.

Gastroprotective effect of Cymbopogon citratus infusion on acute ethanol-induced gastric lesions in rats

ETHNOPHARMACOLOGICAL RELEVANCE

Treatment of gastric ulcers with medicinal plants is quite common in traditional medicine worldwide. Cymbopogon citratus (DC) Stapf. leaves infusion has been used in folk medicine of many tropical and subtropical regions to treat gastric disturbances. The aim of this study was to assess the potential gastroprotective activity of an essential oil-free infusion from C. citratus leaves in acute gastric lesions induced by ethanol in rat.

MATERIALS AND METHODS

The study was performed on adult male Wistar rats (234.0±22.7g) fasted for 24h but with free access to water. The extract was given orally before (prevention) or after (treatment) intragastric administration of absolute ethanol. Effects of dose (28 or 56mg/kg of body weight) and time of contact of the extract with gastric mucosa (1 or 2h) were also assessed. Animals were sacrificed, being the stomachs removed and the lesions were assessed by macroscopic observation and histopathology.

RESULTS

C. citratus extract, given orally before or after ethanol, significantly (P<0.01) reduced gastric mucosal injury compared with control group (vehicle+ethanol). The effect does not appear to be dose-dependent. Results also suggested that the extract is more effective when the time of contact with gastric mucosa increases.

CONCLUSIONS

The results of this assay confirm the gastroprotective activity of C. citratus extract on experimental gastric lesions induced by ethanol, contributing for the pharmacological validation of its traditional use.

Quantification of major compounds from Ixeris dentata, Ixeris dentata Var. albiflora, and Ixeris sonchifolia and their comparative anti-inflammatory activity in lipopolysaccharide-stimulated RAW 264.7 cells

The aim of the present study was to evaluate the comparative anti-inflammatory activities of Ixeris dentata (ID), Ixeris dentata var. albiflora (IDA), and Ixeris sonchifolia (IS) and to identify the main compounds present in extracts. The anti-inflammatory activity was evaluated through lipopolysaccharide (LPS)-induced nitric oxide (NO) production in RAW 264.7 murine macrophages. Five main compounds consisting of chlorogenic acid, caffeic acid, luteolin 7-O-glucoside, luteolin 7-O-glucuronide, and luteolin were used for simultaneous high-performance liquid chromatography quantification. The total phenolic content present in ID (30 mg/g GAE), IDA (35.33 mg/g GAE), and IS (43.79 mg/g GAE) was correlated to the corresponding LPS-induced NO production inhibitory effect in RAW 264.7 cells as expressed with IC(50) values 26.19, 21.43, and 7.59 μg/mL, respectively. Luteolin 7-O-glucoside was found as the major compound in ID (8.76 mg/g dry weight) and IDA (10.35 mg/g dry weight) and luteolin 7-O-glucuronide was the major compound in IS (34.66 mg/g dry weight). Luteolin 7-O-glucoside and luteolin 7-O-glucuronide inhibited LPS-induced NO production with IC(50) values of 30 and 4.5 μM, respectively. Furthermore, luteolin, luteolin 7-O-glucoside, and luteolin 7-O-glucuronide suppressed the expression of iNOS and COX-2, and t-BHP-induced ROS generation in LPS-stimulated RAW 264.7 cells. These results clearly showed that the anti-inflammatory potential of ID, IDA, and IS extract are primarily due to their contents of luteolin 7-O-glucoside and luteolin 7-O-glucuronide, respectively.

Effect of 5-caffeoylquinic acid on the NF-κB signaling pathway, peroxisome proliferator-activated receptor gamma 2, and macrophage infiltration in high-fat diet-fed Sprague-Dawley rat adipose tissue

Obesity, considered as a consequence of overnutrition, sustains a low-degree inflammatory state and results in insulin-resistance and type 2 diabetes. Here, we investigated the anti-inflammatory effects of 5-caffeoylquinic acid (5-CQA) in high-fat diet-induced obese rats. Serum interleukin (IL)-6, monocyte chemotactic protein 1 (MCP-1), tumor necrosis factor-alpha (TNF-α), total cholesterol (TC), triglyceride (TG), and free fatty acid (FFA) levels were determined. Expression of genes related to TG metabolism, macrophage biomarkers, and inflammation was assessed by real-time PCR. Protein expression of NF-κB, PPARγ2, and phosphorylated IκBα was evaluated by western blotting, and the histology of adipose tissue was examined. Supplementation of the rat diet with 5-CQA reduced obesity development, macrophage infiltration, and steatosis. Additionally, 5-CQA decreased the expression of NF-κB and downstream inflammatory cytokines, but increased the expression of PPARγ2, in a dose-dependent manner. Thus, 5-CQA improved obesity and obesity-related metabolic disturbances via PPARγ2 and the NF-κB signaling pathway.

Scientific validation of synergistic antioxidant effects in commercialised mixtures of Cymbopogon citratus and Pterospartum tridentatum or Gomphrena globosa for infusions preparation

Pterospartum tridentatum (L.) Willk., Gomphrena globosa L. and Cymbopogon citratus (DC) Stapf. are examples of medicinal plants with antioxidant properties on their own, but that can be improved when mixed. In the present work, the antioxidant activity and phenolic compounds were determined in the infusions prepared from the individual plants, and from mixtures of these plants in different proportions. P. tridentatum > C. citratus > G. globosa was the order observed for antioxidant efficacy, which can be related to their different composition in phenolic compounds. Synergism was the main effect observed among the tested mixtures, mainly for the infusions prepared from the plants in proportion 40%:60% (either P. tridentatum and C. citratus; or G. globosa and C. citratus). The infusion obtained with 40% of P. tridentatum and 60% of C. citratus gave the highest antioxidant properties. The present study validates the commercialisation of the studied plants combined in specific proportions.

Experimental colitis in mice is attenuated by topical administration of chlorogenic acid

Epidemiological data suggest that the consumption of polyphenol-rich foods reduces the incidence of cancer, coronary heart disease, and inflammation. Chlorogenic acid (CGA), an ester of caffeic and quinic acids, is one of the most abundant polyphenol compounds in human diet with proven biological effectiveness both in vitro and in vivo. The aim of the study is to investigate the possible anti-inflammatory effect of CGA in the gastrointestinal (GI) tract and its mechanism of action. We used a well-established model of colitis, induced by intracolonic (i.c.) administration of trinitrobenzenesulfonic acid (TNBS) in mice. The anti-inflammatory effect of CGA in the colon was evaluated based on the clinical and macroscopic and microscopic parameters. To investigate the mechanism of protective action of CGA, myeloperoxidase (MPO), H2O2, and NF-κB levels were assessed in the colon tissue. CGA administered i.c. at the dose of 20 mg/kg (two times daily) protected against TNBS-induced colitis more effectively than the same dose administered orally (p.o.), as evidenced by significantly lower macroscopic and ulcer scores. Furthermore, CGA (20 mg/kg, i.c.) reduced neutrophil infiltration, as demonstrated by decreased MPO activity. Moreover, CGA suppressed activation of NF-κB, as evidenced by lower levels of phospho-NF-κB/NF-κB ratio in the tissue. CGA did not affect the oxidative stress pathways. CGA exhibits anti-inflammatory properties through reduction of neutrophil infiltration and inhibition of NF-κB-dependent pathways. Our results suggest that CGA may have the potential to become a valuable supplement in the treatment of GI diseases.

Antibacterial activity of berry juices, an in vitro study

OBJECTIVE

The aim of the present study was to evaluate in vitro antibacterial activities of blackcurrant and sea buckthorn juices on bacteria associated with gingival inflammation.

MATERIALS AND METHODS

The growth of selected bacteria (Streptococcus mitis, Streptococcus mutans, Streptococcus sanguinis, Streptococcus gordonii, Staphylococcus aureus, Staphylococcus epidermidis and Pseudomonas aeruginosa) was studied in vitro on agar plates. The content of phenols in the different extracts was measured with HPLC-ESI-MS.

RESULTS

The spectrometric analysis identified that the highest level of the single phenols studied was found for ferulic acid (113 μg/ml) in blackcurrant juice. Sea buckthorn contained low levels of selected phenols. Total bacterial inhibition for all bacterial species studied was found at 20% berry juice concentration with pH varying between 4.1-5.4.

CONCLUSIONS

The present study identified that in vitro bacterial growth on agar plates was inhibited by blackcurrant and sea buckthorn juices and that low juice pH explains bacterial in vitro growth. This may have clinical implications in biofilm development, reducing the risks for both tooth decay and gingivitis.

Scientific evaluation of medicinal plants used for the treatment of abnormal uterine bleeding by Avicenna

PURPOSE

Abnormal uterine bleeding (AUB) is one of the prevalent gynecological disorders that cause considerable morbidity and management of that plays an important role in protecting women's health. This review focuses on medicinal plants mentioned by Avicenna, a great Iranian philosopher and physician (A.D. 980-1037), in his book Canon for treatment of AUB.

METHODS

Medicinal plants mentioned in Canon for treatment of AUB were elicited and searched in electronic databases including PubMed, Scopus, Google Scholar and Cochrane library to find studies that confirmed their efficacy. Data were collected for the years 1980-2014.

RESULTS

The findings included 23 plants belonging to 18 families. Scientific findings have revealed that these plants control AUB through four mechanisms of action including inhibition of inflammatory process, inhibition of prostaglandins production, antiproliferative activity on human cervical cancer cells (HeLa), and estrogenic activity. All of the plants exhibited anti-inflammatory activity in vitro and/or in vivo. Cuscuta chinensis and Portulaca oleracea exhibited estrogenic activity. Boswellia carteri, Lens culinaris, Myrtus communis, Polygonum aviculare, Pistacia lentiscus, and Punica granatum have revealed inhibitory activity on biosynthesis of prostaglandins. Some of the mentioned plants including: Ceratonia siliqua, Cuscuta chinensis, Cuscuta epithymum, Cydonia oblonga, Paeonia sp., Portulaca oleracea, Solanum nigrum, Rumex acetosa and Onopordum acanthium have shown antiproliferative activity on HeLa cells.

CONCLUSION

Investigation of traditional Iranian medicine literatures can lead to the identification of effective natural medicines for the management of AUB; however, conclusive confirmation of the efficacy and safety of these treatments needs more evaluations.

Design and formulation of a topical hydrogel integrating lemongrass-loaded nanosponges with an enhanced antifungal effect: in vitro/in vivo evaluation

Lemongrass oil (LGO) is a volatile oil extracted from the leaves of Cymbopogon citratus that has become one of the most important natural oils in the pharmaceutical industry because of its diverse pharmacologic and clinical effects. However, LGO suffers from low aqueous solubility, which could lead to a reduced effect. Moreover, the instability of its major active constituent, citral, could lead to volatilization, reaction with other formulation ingredients, and consequently, skin irritation. To surmount these problems, this research aims to formulate lemongrass-loaded ethyl cellulose nanosponges with a topical hydrogel with an enhanced antifungal effect and decreased irritation. The minimal inhibitory concentration and minimal fungicidal concentration of LGO against Candida albicans strain ATC 100231, determined using the broth macrodilution method, were found to be 2 and 8 μL/mL, respectively. The emulsion solvent evaporation technique was used for the preparation of the nanosponges. The nanosponge dispersions were then integrated into carbopol hydrogels (0.4%). Nine formulations were prepared based on a 32 full factorial design employing the ethyl cellulose:polyvinyl alcohol ratio and stirring rate as independent variables. The prepared formulations were evaluated for particle size, citral content, and in vitro release. Results revealed that all the nanosponge dispersions were nanosized, with satisfactory citral content and sustained release profiles. Statistical analysis revealed that both ethyl cellulose:polyvinyl alcohol ratio and stirring rate have significant effects on particle size and percentage released after 6 hours; however, the effect of the stirring rate was more prominent on both responses. The selected hydrogel formulation, F9, was subjected to surface morphological investigations, using scanning and transmission electron microscopy, where results showed that the nanosponges possess a spherical uniform shape with a spongy structure, the integrity of which was not affected by integration into the hydrogel. Furthermore, the selected formulation, F9, was tested for skin irritation and antifungal activity against C. albicans, where results confirmed the nonirritancy and the effective antifungal activity of the prepared hydrogel.

Preventive effect of Ligularia fischerion inhibition of nitric oxide in lipopolysaccharide-stimulated RAW 264.7 macrophages depending on cooking method

BACKGROUND

Ligularia fischeri (common name Gomchwi) is known for its pharmaceutical properties and used in the treatment of jaundice, scarlet-fever, rheumatoidal arthritis, and hepatic diseases; however, little is known about its anti-inflammatory effect. In this study the influence of blanching and pan-frying on the anti-inflammatory activity of Ligularia fischeri (LF) was evaluated.

RESULTS

Fresh LF and cooked LF showed no significant effect on the viability of macrophages after 24 h incubation. Fresh LF was found to be the most potent inhibitor of nitric oxide (NO) production at 100 μg/ml, while pan-fried LF showed little inhibitory effect on lipoloysaccharide (LPS) stimulated murine machrophage RAW264.7 cells. In contrast with its effect on NO production, pan-fried LF showed significant attenuation of the expression of inducible nitiric oxide synthase (iNOS) compared with fresh LF. In the cooking method of LF, PGE2 production was not affected in the LPS-induced RAW 264.7 cells. In LPS-induced RAW 264.7 cells, pretreatment by fresh and cooked LF increased COX2 mRNA expression. The 3-O-caffeoylquinic acid content of blanching and pan-frying LF increased by 4.92 and 9.7 fold with blanching and pan-frying respectively in comparison with uncooked LF.

CONCLUSIONS

Regardless of the cooking method, Ligularia fischeri exhibited potent inhibition of NO production through expression of iNOS in LPS-induced RAW264.7 cells.

HPLC-Profiles of Tocopherols, Sugars, and Organic Acids in Three Medicinal Plants Consumed as Infusions

Pterospartum tridentatum (L.) Willk, Gomphrena globosa L., and Cymbopogon citratus (DC.) Stapf are medicinal plants that require a more detailed chemical characterization, given the importance of their consumption as infusions. Therefore, the individual profiles in tocopherols, free sugars, and organic acids were obtained by high performance liquid chromatography (HPLC) coupled to different detectors (fluorescence, refraction index, and photodiode array, resp.). C. citratus revealed the highest content of α-, and total tocopherols, glucose, sucrose, succinic, and ascorbic acids. P. tridentatum presented the highest fructose and total sugars content. Otherwise, G. globosa showed the highest organic acids concentration. As far as we know, this is the first study reporting the mentioned chemical compounds in G. globosa and C. citratus.

Shuang-Huang-Lian exerts anti-inflammatory and anti-oxidative activities in lipopolysaccharide-stimulated murine alveolar macrophages

Shuang-Huang-Lian (SHL) is a traditional Chinese compound formula prepared from Lonicerae Japonicae Flos, Scutellariae Radix and Fructus Forsythiae. In this study, we demonstrate the anti-inflammatory and anti-oxidative activities of SHL in lipopolysaccharide (LPS)-stimulated murine alveolar macrophages (MH-S). SHL significantly reduces the transcriptional and translational levels of iNOS and COX-2 as well as the production of NO and prostaglandin E2 (PGE2). It also suppresses the transcription and translation of inflammatory cytokines production, such as TNF-α, IL-1β and IL-6. These inhibitory effects mainly act via ERK1/2- and p38-mediated AP-1 rather than the NF-κB pathway. In parallel with the anti-inflammatory activity, SHL suppresses LPS-induced intracellular total ROS levels by weakening NADPH oxidase activity, enhancing SOD activity and increasing GSH content. In addition, SHL directly scavenges OH and O2(-). Thus, our study elucidates the anti-inflammatory and anti-oxidative mechanisms of SHL in LPS-stimulated MH-S.