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Lamium album and Lamium purpureum are species belonging to the genus Lamium. Aerial parts of the two species and roots of Lamium album have applications in human and veterinary traditional medicine. Haemostatic properties of butanolic extracts of Lamium species were investigated by two experimental models in Wistar rats: haemostatic test by tail bleeding time determination and acenocoumarolcarrageenan test. Results of the haemostatic test by tail bleeding determination demonstrated haemostatic activity of both extracts. In the acenocoumarol-carrageenan test, only the Lamium album extract showed haemostatic activity, comparable to that of vitamin K. Based on the qualitative chemical data on iridoid glycosides (HPTLC), 8-acetylshanzhiside methyl ester might be assumed to be responsible for haemostatic activity. Based on the acute toxicity test, none of the extracts showed toxicity.

This work was aimed at testing gastroprotective effects of Centaurea cyanus L. (herba) polysaccharides (P) and polyphenols (A) fractions on stress-induced rat ulcer model. Studies evaluating acute toxicity in rats and antioxidant (chemiluminescence method) and antimicrobial (on Staphylococcus aureus ATCC6538 and Escherichia coli ATCC8739 strains) activities of Centaurea cyanus L. (herba) product, which combined polysaccharides and polyphenols fractions (PA), have also been done. Accordingly, in vivo pharmacological studies revealed high influence of PA product (500 mg kg-1 of body weight) on deep, moderate and superficial gastric mucosal lesions, greater than that of chemical reference, Ranitidine. P product was proven more effective than Ranitidine in opposing the emergence of deep necrotic lesions only, suggesting the ability of polysaccharides compounds to consolidate gastric mucous layer as well as their certain tendency for cooperation with polyphenols fractions. The acute toxicity study indicated the lack of toxicity of PA product and maximum tolerated doses greater than 1875 mg kg-1 of body weight. PA product provided augmented scavenger activity and week antimicrobial activity on Staphylococcus aureus ATCC6538 and Escherichia coli ATCC8739 strains, resulting in better opportunities for valorisation of the aerial part of Centaurea cyanus L. species in order to obtain new and effective natural medicines.

Context: Verbascum phlomoides L. (Scrophulariaceae) (mullein) used in the European folk medicine due to its anti-inflammatory and soothing action on the respiratory tract is thoroughly documented in handbooks and scientific literature. Nevertheless, information regarding the influence of the polyphenol content on pharmacological activity is scarce. Objective: This study explored the antioxidant and anti-inflammatory potential of V. phlomoides polyphenol-rich extract. Materials and methods: Dried mullein flowers (200 g) were subjected to water extraction (60 °C, 2 h, herb/solvent ratio = 1/10 m/v) and further to n-butanol partition. Total phenolics were spectrophotometrically determined and specific compounds were evaluated by HPLC. The antioxidant activity was assessed by the 2,2-di(4- tert-octylphenyl)-1-picrylhydrazyl (DPPH) assay. The anti-inflammatory potential of the extract (50-200 μg/mL) was evaluated in vitro by ELISA measurement of ICAM-1 expression in TNF-α-stimulated endothelial cells and in vivo by the rat paw edema assay. Results: The mullein extract contained 4.18% total polyphenols expressed as gallic acid. The main components identified by HPLC were: rosmarinic acid (14.93 mg/g), caffeic acid (39.96 mg/g), ferulic acid (29.61 mg/g) and quercetin (17.29 mg/g). Acteoside was not detected; aucubin was detected in traces (0.028 mg/g). Depending on concentration, the extract exerted scavenging activity on DPPH radical (EC50 7.09 mg/mL), significantly inhibited TNF-α-induced ICAM-1 expression by 55-58.8% on human umbilical vein endothelial cells at 100 and 200 μg/mL, but failed to reduce egg-white-induced rat paw edema. Discussion and conclusion: Mullein polyphenols play an important role in exerting the antioxidant effect but have a weak influence on anti-inflammatory activity that is correlated, probably, to a higher content of iridoids and phenylethanoids. [ABSTRACT FROM AUTHOR]

High-mobility group box protein 1 (HMGB1) is an intracellular protein that may be released actively from monocytes and macrophages or passively from necrotic or damaged cells. Its inhibition in animal experiments, even in the late phase of septic shock, significantly enhanced the survival rate of rodents. The aim of our study was to investigate the effect of a vegetal fraction isolated and highly purified from Helleborus purpurascens regarding the modulation of HMGB1 release either from tumor cells or human blood mononuclear cells. Our results showed that the vegetal fraction was able to down-regulate the release of HMGB1 from activated human blood mononuclear cells (PBMCs) and tumor cells. By combining the purified fraction with Cyclophosphamide the release of HMGB1 from tumor cells was strongly decreased. This synergism was not noticed when the ve getal product was associated with Doxorubicin. We also studied the effect of the purified fraction in mice with septic shock induced by cecal ligation and puncture (CLP) method. The tested vegetal product increased significantly the survival rate of animals compared to the mice not treated with it. Our data suggest that the purified vegetal fraction may modulate inflammation by down-regulating the HMGB1, which can also explain its efficacy in septic shock in mice.