Contribution of C-glucosidic ellagitannins to Lythrum salicaria L. influence on pro-inflammatory functions of human neutrophils

Therapeutic Effects of Oral Application of Menthol and Extracts from Tormentil (Potentilla erecta), Raspberry Leaves (Rubus idaeus), and Loosestrife (Lythrum salicaria) during Acute Murine Campylobacteriosis

Human food-borne infections with the enteropathogen Campylobacter jejuni are becoming increasingly prevalent worldwide. Since antibiotics are usually not indicated in campylobacteriosis, alternative treatment regimens are important. We here investigated potential disease-alleviating effects of menthol and of extracts from tormentil, raspberry leaves, and loosestrife in acute murine campylobacteriosis. Therefore, C. jejuni-infected microbiota-depleted IL-10-/- mice were orally treated with the compounds alone or all in combination from day 2 until day 6 post-infection. Whereas neither treatment regimen affected gastrointestinal pathogen loads, the combination of compounds alleviated C. jejuni-induced diarrheal symptoms in diseased mice on day 6 post-infection. Furthermore, the therapeutic application of tormentil and menthol alone and the combination of the four compounds resulted in lower colonic T cell numbers in infected mice when compared to placebo counterparts. Notably, pro-inflammatory cytokines measured in mesenteric lymph nodes taken from C. jejuni-infected mice following tormentil, menthol, and combination treatment did not differ from basal concentrations. However, neither treatment regimen could dampen extra-intestinal immune responses, including systemic pro-inflammatory cytokine secretion on day 6 post-infection. In conclusion, the combination of menthol and of extracts from tormentil, raspberry leaves, and loosestrife constitutes an antibiotic-independent approach to alleviate campylobacteriosis symptoms.

Infusion from Miconia albicans (Melastomataceae) leaves exhibits anti-inflammatory and anti-hyperalgesic activities without toxicity

ETHNOPHARMACOLOGICAL RELEVANCE

The leaves of Miconia albicans have been extensively used as a traditional medicine to treat inflammation, infection, arthritis, joint pain, and analgesia, which can be purchased easily. Nevertheless, the scientific evidence of chemical profile identification and toxicity investigation is meager.

AIM OF THE STUDY

This study aimed to determine the chemical profile of Miconia albicans aqueous extract (MAAE), to investigate its anti-inflammatory and hyperalgesic effects, and toxicity (acute and repeated-dose oral) in vivo studies.

MATERIALS AND METHODS

MAAE was obtained by infusion method and its chemical constituents were analyzed and annotated by LC-DAD-MS. The in vivo tests were performed with male and female Swiss mice. Toxicity studies were examined by acute (2000 mg/kg) and repeated-dose oral assays (51.2; 256; 1280 mg/kg); anti-inflammatory evaluation was performed by paw edema and leukocyte migration, and anti-hyperalgesic properties were analyzed by abdominal writhing induced by acetic acid and formalin. The animals were treated by oral means with 51.2, 256, and 1280 mg/kg of MAAE.

RESULTS

Twenty-four compounds were annotated from MAAE by LC-DAD-MS, such as ellagitannins, ellagic acid derivatives, flavan-3-ol, and O-glycosylated compounds, including flavonols, triterpenes, and megastigmanes. MAAE induced no significant toxicological effects in the acute and repeated-dose oral assays at lower doses and no histological changes were observed. Hematological and biochemical showed no significant alterations. The oral administration of MAAE 256 mg/kg inhibited the edematogenic effect and reduced the leukocyte migration. In addition, MAAE decreased the abdominal writhings induced by acetic acid and the paw-licking time by formalin assay.

CONCLUSION

MAAE showed a significant reduction in inflammatory levels and leukocyte migration, revealing anti-hyperalgesic properties. Additionally, MAAE revealed no acute and repeated-doses toxicities.

Salicylate and Procyanidin-Rich Stem Extracts of Gaultheria procumbens L. Inhibit Pro-Inflammatory Enzymes and Suppress Pro-Inflammatory and Pro-Oxidant Functions of Human Neutrophils Ex Vivo

Salicylate-rich plants are an attractive alternative to synthetic anti-inflammatory drugs due to a better safety profile and the advantage of complementary anti-inflammatory and antioxidant effects of the co-occurring non-salicylate phytochemicals. Here, the phytochemical value and biological effects in vitro and ex vivo of the stems of one of such plants, Gaultheria procumbens L., were evaluated. The best extrahent for effective recovery of the active stem molecules was established in comparative studies of five extracts. The UHPLC-PDA-ESI-MS³, HPLC-PDA, and UV-photometric assays revealed that the selected acetone extract (AE) accumulates a rich polyphenolic fraction (35 identified constituents; total content 427.2 mg/g dw), mainly flavanols (catechins and proanthocyanidins; 201.3 mg/g dw) and methyl salicylate glycosides (199.9 mg/g dw). The extract and its model components were effective cyclooxygenase-2, lipoxygenase, and hyaluronidase inhibitors; exhibited strong antioxidant capacity in six non-cellular in vitro models (AE and procyanidins); and also significantly and dose-dependently reduced the levels of reactive oxygen species (ROS), and the release of cytokines (IL-1β, IL-8, TNF-α) and proteinases (elastase-2, metalloproteinase-9) in human neutrophils stimulated ex vivo by lipopolysaccharide (LPS) and N-formyl-L-methionyl-L-leucyl-L-phenylalanine (fMLP). The cellular safety of AE was demonstrated by flow cytometry. The results support the application of the plant in traditional medicine and encourage the use of AE for development of new therapeutic agents.

Effect of Fagonia arabica on thrombin induced release of t-PA and complex of PAI-1 tPA in cultured HUVE cells

Fagonia arabica (FA) possesses a thrombolytic property which has been earlier reported in our laboratory. Current study was undertaken to investigate the effect of aqueous extract of FA on thrombin-induced tissue plasminogen activator (t-PA) and plasminogen activator inhibitor-1 (PAI-1) release from cultured human umbilical vein endothelial cell line (HUVE) for studying its clot lytic activity. For this, establishment of cell line model has been done by isolating the cells from human umbilical cord. Cell toxicity was evaluated using XTT assay. Estimation of t-PA and PAI-1 t-PA complex were done using ELISA technique. Thrombin treatment induces the t-PA and PAI-1 release from HUVE cell line, and FA treatment was found to antagonize the thrombin induced t-PA and PAI-1 release. Our preliminary results suggest that FA may be used as an alternative to thrombolytic drug. However, study demands further experiments using animal model of thrombosis to establish the role of FA as a novel thrombolytic drug.

Herbs as an antioxidant arsenal for periodontal diseases

Herbal medicines have long been used as a traditional mode of therapy for various ailments in India. They are being used increasingly as dietary supplements to ward off common diseases. Periodontal diseases are highly prevalent and can affect up to 90% of the world population. Gingivitis is the mild form whereas periodontitis results in an irreversible loss of supporting structures of the teeth. Even though periodontal pathogens form a crucial component in the etiopathogenesis of periodontitis, there is a growing body of evidence suggesting oxidative stress playing a pivotal role in the disease initiation and progression. Studies have shown a direct correlation between increased levels of biomarkers for tissue damage induced by reactive oxygen species (ROS) to the severity of periodontal disease. Thus, the focus of attention has revolved back to herbal medicines due to their wide spectrum of biological and medicinal activities, lower costs, and higher safety margin. Internet databases Pubmed and Google Scholar were searched, and the most relevant articles were considered for review. This review briefly describes the various herbs with antioxidant capacity and their potency in the treating periodontal disease.

Ellagitannins modulate the inflammatory response of human neutrophils ex vivo

BACKGROUND

Tannin-rich plant materials are commonly used in the traditional medicine as external anti-inflammatory, antioxidant and antimicrobial agents. Plant extracts containing significant quantities of tannins are often used in the prevention and treatment of oral cavity diseases such as periodontosis or gingivitis. The contribution of pure ellagitannins to the observed anti-inflammatory activity of tannin-rich remedies is still not resolved.

PURPOSE

The aim of the present study the study was to establish if ellagitannins and their precursor - pentagalloylglucose (1) can modulate the inflammatory response of ex-vivo stimulated neutrophils.

METHODS

Human neutrophils were isolated from the buffy coats obtained from healthy volunteers. Neutrophils were cultivated with or without tested compounds. The influence of ellagitannins and 1 on the production and release of pro-inflammatory factors such as elastase, reactive oxygen species, interleukin-8, tumour necrosis factor alpha (TNF-α) and metalloproteinase-9 was evaluated using ELISA sets or chemical methods. The effect on surface expression of toll like receptor 4 (TLR-4) and apoptosis was also checked using flow cytometry.

RESULTS

The results showed that ellgitannins modulate the inflammatory response of human neutrophils by the inhibition of production and release of chosen cytokines and pro-inflammatory enzymes. By the induction of TNF-α ellagitannins enhance neutrophil apoptosis, which is of interest in the case of chronic inflammation within oral cavity. Ellagitannins also decrease the surface expression of TLR-4 in activated neutrophils.

CONCLUSION

The results support the traditional use of tannin-rich products in the prevention and treatment of oral cavity diseases. The present study proves the substantial contribution of ellagitannins to the anti-inflammatory activity of tannin-rich medicinal plant materials.

Lythrum salicaria L.-Underestimated medicinal plant from European traditional medicine. A review

ETHNOPHARMACOLOGICAL RELEVANCE

Purple loosestrife-Lythrum salicaria L. is a herbaceous perennial plant belonging to the Lythraceae family. It has been used for centuries in European traditional medicine. Despite Lythri herba being a pharmacopoeial plant material (Ph. Eur.), L. salicaria popularity as a medicinal plant has recently declined. The aim of the paper is to recall a traditional and historical use of L. salicaria and juxtapose it with comprehensive view on the current knowledge about its chemical composition and documented biological activities in order to bring back the interest into this valuable plant and indicate reasonable directions of future research and possible applications.

MATERIALS AND METHODS

Systematic survey of historical and ethnopharmacological literature was carried out using sources of European and American libraries. Pharmacological and phytochemical literature research was performed using Scopus, PubMed, Web of Science and Reaxys databases.

RESULTS

The review of historical sources from ancient times till 20th century revealed an outstanding position of L. salicaria in traditional medicine. The main applications indicated were gastrointestinal tract ailments (mainly dysentery and diarrhea) as well as different skin and mucosa affections. The current phytochemical studies have shown that polyphenols (C-glucosidic ellagitannins and C-glucosidic flavonoids) as well as heteropolysaccharides are dominating constituents, which probably determine the observed pharmacological effects. The extracts and some isolated compounds were shown to possess antidiarrheal, antimicrobial, anti-oxidant, anti-inflammatory and anti-diabetic activities.

CONCLUSIONS

The intrinsic literature overview conclusively demonstrates that L. salicaria L. used to be considered as an exceptionally effective remedy in European traditional medicine. Despite its unquestionable important position from unknown reasons its popularity has been weakened during the past few decades. Unfortunately the contemporary pharmacological research is still insufficient to support its thoroughly described traditional uses. The necessity of complex studies regarding modes of action, which would directly refer to L. salicaria main traditional applications-gastrointestinal tract ailments, is strongly underlined.