HPLC Analysis of Polyphenolic Compounds and Antioxidant Activity inNasturtium officinale

The hydroalcoholic extract of Nasturtium officinale reduces oxidative stress markers and increases total antioxidant capacity in patients with asthma

ETHNOPHARMACOLOGICAL RELEVANCE

Asthma is a common chronic disease characterized by inflammation of the airways. One of the most devastating consequences of this inflammatory process is the production of reactive oxygen species responsible for oxidative stress. Nasturtium officinale commonly known as watercress has traditionally been applied in Iranian folk medicine to treat respiratory disorders and diseases mainly bronchitis and asthma. In accordance with these ethnopharmacological reports, through our previous in vivo experiment, we have confirmed significant effect of its hydroalcoholic extract in reducing lung inflammation and oxidative stress in an ovalbumin-induced asthmatic rat model.

AIM OF THE STUDY

The aim of the present study was to investigate the anti-inflammatory and antioxidant effects of N. officinale hydroalcoholic extract (NOE) in patients with asthma, in order to confirm our findings of the previous performed in vivo study.

MATERIAL AND METHODS

The NOE capsules (500 mg) were treated twice daily for 4 weeks as a supplementary treatment in a randomized, double-blind, and placebo-controlled trial in asthmatics. The primary outcome was Asthma Control Test score. The blood samples were taken at the beginning and end of the study. Then, the level of inflammatory markers, oxidative stress markers and antioxidant enzyme activity were measured.

RESULTS

Treatment with NOE for one month caused a reduction in the levels of MDA, PCO and NO metabolite markers compared to the placebo group. In addition, FRAP levels as an indicator of total antioxidant capacity in the intervention group was significantly increased at the end of the treatment period compared to pre-treatment values.

CONCLUSION

Findings demonstrated that NOE may have a therapeutic effect on asthma by improving oxidative stress. However, more studies are required to support these results. Moreover, bio-assay guided fractionation and isolation approach can be conducted to identify major bioactive compound/s.

GC-MS and HPLC supported phytochemical analysis of watercress and the protective role against paraben toxicity

In this study, the phytochemical content of Nasturtium officinale R. Br. (watercress) leaf extract (Noex) and its protective effects against paraben toxicity were investigated. GC-MS and HPLC analyses were performed to determine the phytochemical content. Paraben toxicity and protective properties of Noex were investigated with the Allium test, and 6 different groups were formed for this purpose. Toxicity in each group was investigated by using physiological, cytogenetic, biochemical, and anatomical parameters. DNA-paraben interaction was investigated with spectroscopic analysis for the genotoxicity mechanism. As a result of the study, paraben (500 mM) caused a regression in the physiological parameters related to germination in Allium cepa L. bulbs. Paraben caused a 43.3% reduction in mitotic index (MI) rates compared to control, which is likely the reason for the decrease in germination-related parameters. With the application of paraben in root tip cells, the frequency of micronucleus (MN) and chromosomal aberrations (CAs) increased and a high genotoxic effect was observed. Paraben promoted CAs such as fragment, sticky chromosome, bridge, unequal distribution of chromatin, and irregular mitosis. It also caused anatomical damage in the form of epidermis cell damage, flattened cell nucleus, cortex cell damage, cortex cell walls thickening, and unclear vascular tissue in root tip meristem cells. Paraben-DNA interaction was caused by bathochromic and hypochromic shifts in the UV spectrum of DNA, indicating the intercalation mode of interaction. Paraben also caused an increase in malondialdehyde (MDA) levels, a decrease in glutathione (GSH) levels, and abnormalities in antioxidant enzyme levels (superoxide dismutase = SOD and catalase = CAT), thereby disrupting the antioxidant/oxidant dynamics in the cell. The basis of physiological, cytological, and genetic abnormalities was attributed to the oxidative stress in the cell. Administration of Noex produced a dose-dependent incremental improvement in paraben-induced abnormalities. The increase in GSH levels and the decrease in MDA levels observed as a result of the Noex application contributed to the restoration of antioxidant/oxidant balance, and this improvement was also reflected in other parameters. Application of 200 mg/L Noex provided a 24.2% improvement in the MI rate reduced by paraben, and accordingly, an increase in germination parameters was observed. Similarly, the frequencies of MN and CAs, which are signs of genotoxicity, decreased with the Noex application. As a result of the phytochemical analysis of Noex with HPLC and GC-MS, the presence of strong antioxidant and antimutagenic substances such as rutin, coumaric acid, ferrulic acid, L-serine, L-proline, and phytol were determined in Noex structure. The curative effects of Noex against paraben toxicity can be attributed to these active ingredients.

Impacts of elicitors on metabolite production and on antioxidant potential and tyrosinase inhibition in watercress microshoot cultures

The study has proved the stimulating effects of different strategies of treatments with elicitors on the production of glucosinolates (GSLs), flavonoids, polyphenols, saccharides, and photosynthetic pigments in watercress (Nasturtium officinale) microshoot cultures. The study also assessed antioxidant and anti-melanin activities. The following elicitors were tested: ethephon (ETH), methyl jasmonate (MeJA), sodium salicylate (NaSA), and yeast extract (YeE) and were added on day 10 of the growth period. Cultures not treated with the elicitor were used as control. The total GSL content estimations and UHPLC-DAD-MS/MS analyses showed that elicitation influenced the qualitative and quantitative profiles of GSLs. MeJA stimulated the production of gluconasturtiin (68.34 mg/100 g dried weight (DW)) and glucobrassicin (65.95 mg/100 g DW). The elicitation also increased flavonoid accumulation (max. 1131.33 mg/100 g DW, for 100 μM NaSA, collection after 24 h). The elicitors did not boost the total polyphenol content. NaSA at 100 μM increased the production of total chlorophyll a and b (5.7 times after 24 h of treatment), and 50 μM NaSA caused a 6.5 times higher production of carotenoids after 8 days of treatment. The antioxidant potential (assessed with the CUPRAC FRAP and DPPH assays) increased most after 24 h of treatment with 100 μM MeJA. The assessment of anti-melanin activities showed that the microshoot extracts were able to cause inhibition of tyrosinase (max. 27.84% for 1250 µg/mL). KEY POINTS: • Elicitation stimulated of the metabolite production in N. officinale microshoots. • High production of pro-health glucosinolates and polyphenols was obtained. • N. officinale microshoots have got tyrosinase inhibition potential. • The antioxidant potential of N. officinale microshoots was evaluated.

Precursor-Boosted Production of Metabolites in Nasturtium officinale Microshoots Grown in Plantform Bioreactors, and Antioxidant and Antimicrobial Activities of Biomass Extracts

The study demonstrated the effects of precursor feeding on the production of glucosinolates (GSLs), flavonoids, polyphenols, saccharides, and photosynthetic pigments in Nasturtium officinale microshoot cultures grown in Plantform bioreactors. It also evaluated the antioxidant and antimicrobial activities of extracts. L-phenylalanine (Phe) and L-tryptophan (Trp) as precursors were tested at 0.05, 0.1, 0.5, 1.0, and 3.0 mM. They were added at the beginning (day 0) or on day 10 of the culture. Microshoots were harvested after 20 days. Microshoots treated with 3.0 mM Phe (day 0) had the highest total GSL content (269.20 mg/100 g DW). The qualitative and quantitative profiles of the GSLs (UHPLC-DAD-MS/MS) were influenced by precursor feeding. Phe at 3.0 mM stimulated the best production of 4-methoxyglucobrassicin (149.99 mg/100 g DW) and gluconasturtiin (36.17 mg/100 g DW). Total flavonoids increased to a maximum of 1364.38 mg/100 g DW with 3.0 mM Phe (day 0), and polyphenols to a maximum of 1062.76 mg/100 g DW with 3.0 mM Trp (day 0). The precursors also increased the amounts of p-coumaric and ferulic acids, and rutoside, and generally increased the production of active photosynthetic pigments. Antioxidant potential increased the most with 0.1 mM Phe (day 0) (CUPRAC, FRAP), and with 0.5 mM Trp (day 10) (DPPH). The extracts of microshoots treated with 3.0 mM Phe (day 0) showed the most promising bacteriostatic activity against microaerobic Gram-positive acne strains (MIC 250–500 µg/mL, 20–21 mm inhibition zones). No extract was cytotoxic to normal human fibroblasts over the tested concentration range (up to 250 μg/mL).

The Effect of the Hydroalcoholic Extract of Watercress on the Levels of Protein Carbonyl, Inflammatory Markers, and Vitamin E in Chronic Hemodialysis Patients

Introduction

Chronic kidney disorder is a main public health concern. Inflammatory processes and oxidative stress are common in end-stage renal disease patients. We aimed to evaluate the effect of the hydroalcoholic extract of watercress (WC) on the inflammatory cytokines and protein carbonyl (PCO) contents in chronic hemodialysis patients.

Methods

This was a double-blind randomized clinical trial performed on 46 hemodialysis patients. The participants were randomly divided into two groups: intervention group (500 mg hydroalcoholic extract of WC every day for 4 weeks) and control group (500 mg of white flour every night for 4 weeks). The blood samples were taken to determine the levels of vitamin E, PCO, and inflammatory cytokines at baseline and the end of treatment.

Results

Forty-five patients completed the study (22 patients in the intervention group and 23 patients in the control group). There was a significant reduction in the PCO level (20.33 ± 4.40 vs. 15.06 ± 6.41, P=0.001) in the intervention group; also, this change was statistically significant relative to the control group. Furthermore, there were significant reductions in hs-CRP (8953.30 ± 5588.06 vs. 7249.86 ± 5091.62, P=0.007) and IL-6 (60.10 (55.99, 73.10) vs. 55.21 (53.39, 60.48), P=0.050) in the intervention group, but these changes were not significant in comparison with the control group.

Conclusion

We conclude that the hydroalcoholic extract of WC reduced the PCO content in hemodialysis patients via inhibition of protein oxidation. Although WC administration had caused a significant reduction in IL-6 and CRP levels, these differences were not statistically significant relative to the control group. Further research is needed to identify the antioxidant and anti-inflammatory effects of WC in hemodialysis patients.

A Narrative Review on Therapeutic Potentials of Watercress in Human Disorders

Watercress (WC) is an aquatic vegetable that belongs to the Brassicaceae family, and it often grows near water. In traditional medicine, WC is a known remedy for hypercholesterolemia, hyperglycemia, hypertension, arthritis, bronchitis, diuresis, odontalgia, and scurvy. It also acts as an antiestrogenic and can be used as a nutritional supplement. It has been reported that these therapeutic effects are due to primary metabolites such as isothiocyanates, glucosinolates, polyphenols (flavonoids, phenolic acids, and proanthocyanidins), vitamins (B₁, B₂, B₃, B₆, E, and C), terpenes (including carotenoids), and bioelements which exist in this plant. Many pharmacological studies confirm the antioxidant, antibacterial, anticancer, antipsoriatic, anti-inflammatory, cardioprotective, renoprotective, hepatoprotective, and antigenotoxicity effects of WC. The consumption of WC extract can be useful in reducing the complications of hypercholesterolemia and hyperglycemia. Furthermore, the extract of WC could markedly augment the antioxidant enzymes such as superoxide dismutase and catalase activity. Interestingly, consumption of food rich in polyphenols such as WC extract can help reduce oxidative stress, DNA damage, and cancer susceptibility. Several studies also showed that WC extract significantly reduced liver injury as a result of cholestatic hepatic injury, gamma radiation, arsenic, and acetaminophen-induced hepatotoxicity. In this review, the researchers focus on the phytochemical and biochemical characterizations of WC and its therapeutic effects in the treatment of human diseases.

Effects of Nasturtium officinale Extract on Antioxidant and Biochemical Parameters in Hemodialysis Patients: A Randomized Double-Blind Clinical Trial

Background

Increased oxidative stress play an important role in the risk of cardiovascular disease, mortality, and mortality patients undergoing dialysis. Nasturtium officinale (watercress) contains numerous phytochemical compounds that act as an antioxidant by preventing oxidative damage to biomolecules. Therefore, this research aimed to explore the effect of the ethanolic extract of Nasturtium officinale (EENO) on antioxidant and biochemical markers of hemodialysis patients.

Methods

In this double-blind, placebo-controlled trial, 46 hemodialysis patients were randomly recruited to consume either 500 mg/day EENO (n = 23) or placebo capsule (n = 23) for 4 weeks, at Shahid Beheshti Hospital, Yasuj, Iran, in 2019. Biomarkers of oxidative stress including glutathione peroxidase (GPX), superoxide dismutase (SOD), malondialdehyde (MDA), total oxidant status (TOS), total antioxidant capacity (TAC), and total sulfhydryl protein (T-SH) and biochemical parameters such as BUN, Hb, WBC, PLT, Ca, Ph, K, ALB, TChol, TG, LDL, and HDL were evaluated on days 0 and 28.

Results

The serum levels of MDA and BUN significantly decreased after taking EENO supplementation (P < 0.001); however, SOD activity increased during the same period (P < 0.001). The serum levels of TAC remained constant in the intervention group, while it significantly declined in the placebo group (P < 0.09). The extract also prevented elevation in the serum levels of LDL and TG compared to the placebo group, although it was not statistically significant.

Conclusions

The data indicated that the consumption of EENO improved some of the antioxidant parameters and minimizes the change in TG and LDL in hemodialysis patients. Therefore, due to the role of these factors in mortality and morbidity of dialysis patients, EENO can improve the condition of dialysis patients. However, more studies with longer intervention times and different doses of EENO are recommended.

Phytochemical and Biological Activity Studies on Nasturtium officinale (Watercress) Microshoot Cultures Grown in RITA® Temporary Immersion Systems

The main compounds in both extracts were gluconasturtiin, 4-methoxyglucobrassicin and rutoside, the amounts of which were, respectively, determined as 182.93, 58.86 and 23.24 mg/100 g dry weight (DW) in biomass extracts and 640.94, 23.47 and 7.20 mg/100 g DW in plant herb extracts. The antioxidant potential of all the studied extracts evaluated using CUPRAC (CUPric Reducing Antioxidant Activity), FRAP (Ferric Reducing Ability of Plasma), and DPPH (1,1-diphenyl-2-picrylhydrazyl) assays was comparable. The anti-inflammatory activity of the extracts was tested based on the inhibition of 15-lipoxygenase, cyclooxygenase-1, cyclooxygenase-2 (COX-2), and phospholipase A₂. The results demonstrate significantly higher inhibition of COX-2 for in vitro cultured biomass compared with the herb extracts (75.4 and 41.1%, respectively). Moreover, all the studied extracts showed almost similar antibacterial and antifungal potential. Based on these findings, and due to the fact that the growth of in vitro microshoots is independent of environmental conditions and unaffected by environmental pollution, we propose that biomass that can be rapidly grown in RITA^® bioreactors can serve as an alternative source of bioactive compounds with valuable biological properties.

The Influence of Nasturtium officinale R. Br. Agar and Agitated Microshoot Culture Media on Glucosinolate and Phenolic Acid Production, and Antioxidant Activity

This paper presents an optimization of conditions for microshoot cultures of Nasturtium officinale R. Br. (watercress). Variants of the Murashige and Skoog (MS) medium containing different plant growth regulators (PGRs): cytokinins—BA (6-benzyladenine), 2iP (6-γ,γ-dimethylallylaminopurine), KIN (kinetin), Zea (zeatin), and auxins—IAA (3-indoleacetic acid), IBA (indole-3-butyric acid), 2,4-d (2,4-dichlorophenoxyacetic acid), IPA (indole-3-pyruvic acid), NAA (naphthalene-1-acetic acid), total 27 MS variants, were tested in agar and agitated cultures. Growth cycles were tested for 10, 20, or 30 days in the agar cultures, and 10 or 20 days in the agitated cultures. Glucosinolate and phenolic acid production, total phenolic content and antioxidant potential were evaluated. The total amounts of glucosinolates ranged from 100.23 to 194.77 mg/100 g dry weight of biomass (DW) in agar cultures, and from 78.09 to 182.80 mg/100 g DW in agitated cultures. The total phenolic acid content varied from 15.89 to 237.52 mg/100 g DW for the agar cultures, and from 70.80 to 236.74 mg/100 g DW for the agitated cultures. Extracts of the cultured biomass contained higher total amounts of phenolic acids, lower total amounts of glucosinolates, a higher total phenolic content and similar antioxidant potentials compared to plant material. The analyses performed confirmed for the first time the explicit influence on secondary metabolite production and on the antioxidant potential. The significance was statistically estimated in a complex manner.

Protective effect of Nasturtium officinale R. Br and quercetin against cyclophosphamide-induced hepatotoxicity in rats

Cyclophosphamide (CPA) is used in the management of autoimmune conditions and malignant illnesses. However, its therapeutic use is limited because of its severe side effects, especially hepatotoxicity attributed to oxidative stress. Nasturtium officinale R. Br (watercress or WC) has pharmacological properties, such as anti-inflammation, and antioxidant activities. Therefore, the present study was design to assess effects of WC or its active ingredient, quercetin (QE), against CPA-induced hepatotoxicity. For this study, 49 male Wistar rats (200-250 g) were randomly selected and categorized into seven equal groups. The animals were pre- and post-treated with both hydroalcoholic extract of WC (500 mg/kg) and quercetin (75 mg/kg) for 10 consecutive days, and intraperitoneal administration of CPA (200 mg/kg) was performed on only day 10, one hour before the last dose of WC or quercetin. On day 11, all the animals were sacrificed, and their blood and liver were gathered for evaluation of the liver enzyme, hepatic oxidative stress markers, antioxidant enzymes activity, and hematoxylin and eosin staining. CPA significantly increased malondialdehyde (MDA), protein carbonyl (PCO) and nitric oxide (NO) levels and liver biomarkers. Otherwise, hepatic catalase (CAT), reduced glutathione (GSH), total thiol content (tSH), and ferric reducing antioxidant power (FRAP) were considerably lower than the control group. Results showed that WC has the ability to reduce the changes (MDA, PCO, FRAP, CAT, ALT and AST) and QE (MDA, PCO, AST) induced by CPA (p < 0.05). Histopathological finding confirmed the indicated results. These findings propose that WC and QE have protective effect against the CPA-induced hepatotoxicity by decreasing oxidative stress.

Croton campestris A. St.-Hill Methanolic Fraction in a Chlorpyrifos-Induced Toxicity Model in Drosophila melanogaster: Protective Role of Gallic Acid

Croton campestris A. St-Hill popularly known as "velame do campo" is a native species of the savannah from northeastern Brazil, being used in folk medicine due to its beneficial effects in the treatment of many diseases, inflammation, detoxification, gastritis, and syphilis; however, its potential use as an antidote against organophosphorus compound poisoning has not yet been shown. Here, the protective effect of the methanolic fraction of C. campestris A. St.-Hill (MFCC) in Drosophila melanogaster exposed to chlorpyrifos (CP) was investigated. Flies were exposed to CP and MFCC during 48 h through the diet. Following the treatments, parameters such as mortality, locomotor behavior, and oxidative stress markers were evaluated. Exposure of flies to CP induced significant impairments in survival and locomotor performance. In parallel, increased reactive oxygen species and lipoperoxidation occurred. In addition, the activity of acetylcholinesterase was inhibited by CP, and superoxide dismutase and glutathione S-transferase activity was induced. Treatment with MFCC resulted in a blockage of all CP-induced effects, with the exception of glutathione S-transferase. Among the major compounds found in MFCC, only gallic acid (GA) showed a protective role against CP while quercetin and caffeic acid alone were ineffective. When in combination, these compounds avoided the toxicity of CP at the same level as GA. As far as we know, this is the first study reporting the protective effect of MFCC against organophosphate toxicity in vivo and highlights the biotechnological potential of this fraction attributing a major role in mediating the observed effects to GA. Therefore, MFCC may be considered a promising source for the development of new therapeutic agents for the treatment of organophosphate intoxications.

Nasturtium officinale R. Br. effectively reduces the skin inflammation induced by croton oil via glucocorticoid receptor-dependent and NF-κB pathways without causing toxicological effects in mice

ETHNOPHARMACOLOGICAL RELEVANCE

Inflammatory skin diseases treatments currently used cause adverse effects. Nasturtium officinale (watercress) is used popularly as an anti-inflammatory. However, until now, no study proved its effectiveness as a topical treatment to inflammatory skin diseases. The topical anti-inflammatory activity of N. officinale crude extract leaves (NoE) on an irritant contact dermatitis (ICD) model croton oil-induced in mice was investigated.

MATERIALS AND METHODS

ICD models were induced by a single (1 mg/ear; acute) or repeated (0.4 mg/ear; chronic; 9 days total) croton oil application. NoE and dexamethasone solutions' (diluted in acetone; 20 μL/ear) or NoE gel, dexamethasone gel and base gel (15 mg/ear) were topically applied immediately after croton oil application. The NoE topical anti-inflammatory effect was evaluated for inflammatory parameters (ear edema, inflammatory cells infiltration, and inflammatory cytokines levels). NoE topical anti-inflammatory mechanism (NF-κB pathway and effect glucocorticoid-like) were assessed by western blot and ear edema analyses, respectively. UHPLC-MS/MS chromatography, gels accelerated stability and preliminary study of adverse effects was also performed.

RESULTS

UHPLC-MS/MS of the NoE revealed the presence of coumaric acid, rutin, and ferulic acid. NoE gels stability study showed no relevant changes at low temperature. NoE, dexamethasone, NoE gel and dexamethasone gel inhibited the ear edema croton oil-induced by 82 ± 6% (1 mg/ear), 99 ± 1% (0.1 mg/ear), 81 ± 8% (3%) and 70 ± 6% (0.5%) for the acute model, and 49 ± 7% (1 mg/ear), 80 ± 4% (0.1 mg/ear), 41 ± 8% (3%) and 46 ± 14% (0.5%) for the chronic model, respectively. The same treatments also reduced the inflammatory cells infiltration by 62 ± 3% (1 mg/ear), 97 ± 2% (0.1 mg/ear), 60 ± 3% (3%) and 66 ± 6% (0.5%) for the acute model, respectively, and 25 ± 8% (1 mg/ear) to NoE and 83 ± 13% to dexamethasone to the chronic model. NoE and NoE gel reduced the pro-inflammatory cytokines levels (acute ICD model) by 62 ± 5% and 71 ± 3% (MIP-2) and 32 ± 3% and 44 ± 4% (IL-1β), while dexamethasone solution's and gel reduced by 79 ± 7% and 44 ± 4% to MIP-2 and 98 ± 2% and 83 ± 9% to IL-1β, respectively. NoE' and dexamethasone' solutions inhibited the reduction of IkB-α protein expression induced by croton oil by 100% and 80 ± 14%, respectively. Besides, the mifepristone (glucocorticoid receptor antagonist) pre-treatment prevented the topical anti-edematogenic effect of NoE' and dexamethasone' solutions by 61 ± 5% to NoE and 78 ± 16% to dexamethasone. The repeated topical application of NoE did not cause adverse effects.

CONCLUSION

Our results suggest the N. officinale use in the cutaneous inflammatory process treatment and demonstrate the NoE potential to develop a promising topical anti-inflammatory agent to treat inflammatory disorders.

Chemical composition, traditional and professional use in medicine, application in environmental protection, position in food and cosmetics industries, and biotechnological studies of Nasturtium officinale (watercress) - a review

The herb of Nasturtium officinale is a raw material that has long been used in the traditional medicine of Iran, Azerbaijan, Morocco and Mauritius. Nowadays, this raw material is the object of numerous professional pharmacological studies that have demonstrated its antioxidant, anticancer, antibacterial, anti-inflammatory and cardioprotective properties. These therapeutic effects are caused by glucosinolates present in the plant, isothiocyanates, polyphenols (flavonoids, phenolic acids, proanthocyanidins), terpenes (including carotenoids), vitamins (B₁, B₂, B₃, B₆, E, C) and bioelements. The article presents the current state of phytochemical research on the generative and vegetative organs of the plant. A special spotlight is put on the main N. officinale secondary metabolites - glucosinolates. Attention is drawn to the important position of N. officinale in the production of healthy foods and in the production of cosmetics. A large part of the article is devoted to the importance of this species in phytoremediation processes used in the protection of soil environments and water reservoirs. The biotechnological research on this species has also been reviewed. Those studies are of particular importance not only due to the attractiveness of this species in phytotherapy and cosmetology, but also due to the deteriorating natural state of this species and the threat of extinction. The aim of this review is to promote N. officinale as a very valuable species, not yet fully discovered by global medicine.

In vivo anti-inflammatory properties of aerial parts of Nasturtium officinale

CONTEXT

Nasturtium officinale R. Br. (watercress) has long been used in Iranian folk medicine to treat hypertension, hyperglycemia, and renal colic. Moreover, anticancer, antioxidant, and hepatoprotective properties of N. officinale have been reported.

OBJECTIVE

In this study, anti-inflammatory activity of the hydro-alcoholic extract from aerial parts of N. officinale was investigated.

MATERIALS AND METHODS

Oral administration of the hydro-alcoholic extract of N. officinale (250, 500 and 750 mg kg(-1)) was investigated on two well-characterized animal models of inflammation, including carrageenan- or formalin-induced paw edema in rats. Then, the topical anti-inflammatory effect of N. officinale (2 and 5 mg/ear) was studied on 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced mouse ear edema. Finally, biopsy of the paw or ear was performed for pathological evaluation.

RESULTS

Acute toxicity tests of N. officinale in rats established an oral LD50 of >5 g kg(-1). The extract of watercress (250, 500 and 750 mg kg(-1)) significantly inhibited carrageenan-induced paw edema 1, 2, 3 and 4 h after carrageenan challenge (p < 0.001). The extract (500 mg kg(-1)) also showed considerable activity against formalin-evoked paw edema over a period of 24 h (p < 0.001). Furthermore, topical application of N. officinale (5 mg/ear) reduced TPA-induced ear edema (p < 0.05). Histopathologically, the extract decreased swelling and the tissue damage induced by carrageenan or TPA.

DISCUSSION AND CONCLUSION

Our findings indicate potent anti-inflammatory activity of N. officinale in systemic and topical application and propose its potential as an anti-inflammatory agent for treatment of inflammatory conditions.