Overview of the phytomedicine approaches against Helicobacter pylori

Helicobacter pylori(H.pylori)successfully colonizes thehuman stomach of the majority of the human popula-tion.This infection always causes chronic gastritis,butmay evolve to serious outcomes,such as peptic ulcer,gastric carcinoma or mucosa-associated lymphoid tis-sue lymphoma.H.pylori first line therapy recommend-ed by the Maastricht-4 Consensus Report comprises theuse of two antibiotics and a proton-pomp inhibitor,butin some regions failure associated with this treatmentis already undesirable high.Indeed,treatment failure isone of the major problems associated with H.pylori in-fection and is mainly associated with bacterial antibioticresistance.In order to counteract this situation,someeffort has been allocated during the last years in theinvestigation of therapeutic alternatives beyond antibi-otics.These include vaccines,probiotics,photodynamic inactivation and phage therapy,which are briefly revis-ited in this review.A particular focus on phytomedicine,also described as herbal therapy and botanical therapy,which consists in the use of plant extracts for medicinal purposes,is specifically addressed,namely considering its history,category of performed studies,tested com-pounds,active principle and mode of action.The herbs already experienced are highly diverse and usually selected from products with a long history of employ-ment against diseases associated with H.pylori infec-tion from each country own folk medicine.The studies demonstrated that many phytomedicine products have an anti-H.pylori activity and gastroprotective action.Al-though the mechanism of action is far from being com-pletely understood,current knowledge correlates the beneficial action of herbs with inhibition of essential H.pylori enzymes,modulation of the host immune system and with attenuation of inflammation.

Animal models of acute gastric mucosal injury: Macroscopic and microscopic evaluation

Acute gastric mucosal injury is a common disorder of the gastrointestinal tract and the search for new therapeutics is ongoing. The aim of this study is to update and expand the information related to the most widely used rat models of acute gastric ulcer, the ethanol‐induced ulcer and the indomethacin‐induced ulcer. These two models are compared in terms of macroscopic and microscopic features. Experimentally, ethanol was given orally in a single dose and indomethacin was subcutaneously injected into male Wistar rats. After ulcerative challenges, the stomachs were removed and visually inspected. Anti‐ulcerative drugs were used to validate the models. Histological analysis of the stomachs determined the microscopic score. The methodology used for model evaluation applied to macroscopic and microscopic gastric lesions. With these methods it was possible to induce lesions in the gastric mucosa. Microscopic evaluation permitted assessment of the inflammatory and apoptotic impact in the mucosa not observable by macroscopic evaluation. Groups of animals were treated with two standard drugs: sulcralfate suspension or lansoprazole solution. Both drugs reduced macroscopic and microscopic lesions, particularly the hemorrhagic ones. Both models induced acute gastric mucosal injury and no single evaluation method can address all the aspects of the pathology of gastric lesions. As a complement to macroscopic evaluation, microscopy appears to be a relevant tool to selectively identify specific aspects of the development of mucosal injury, quantify the extent of lesions, and contribute to an appropriate interpretation of results. The score systems established here offer a reliable method for testing antiulcer drugs.

Food,polyphenols and neuroprotection

Neuron loss and neurodegeneration are the common denom- inators of what are known as neurodegenerative diseases. Although the clinical manifestations of some neurodegenerative diseases are mainly associated with ageing, it is believed that onset of disease and neuronal death occurs progressively through life, well betore the first symptoms appear. So, one of the main dilemmas regarding neurodegenerative disease ther-apies is that treatment often starts long after the neurodegeneration has occurred, when a great number of neurons have already been lost. Furthermore,

Green Tea(Camellia sinensis):Hypocholesterolemic Effects in Humans and Anti-Inflammatory Effects in Animals

In its essence, tea is an infusion of Camellia sinensis leaves and it is the most widely consumed beverage in the world, aside water. Animal and epidemiological studies have associated green tea consumption with several health benefits, which include hypocholesterolemic effect and anti-in-flammatory activity. In this study catechins levels of green tea and its effect on the lipid profile of humans were evaluated as well as the protective effects against H2O2-mediated damage in human fibroblasts and anti-inflammatory activity of (–)-epigallocatechingallate (EGCG). The daily consumption of 1200 mL of green tea for 30 days by 15 human volunteers promoted the decrease of cholesterol and LDL levels after 15 days, but this effect was not persistent after 30 days. No changes were observed in lipid profile after the consumption of green tea capsules. EGCG, a major green tea catechin, demonstrated an anti-inflammatory action in rats and an antioxidant effect in cultured human fibroblasts.

Skin models of cutaneous toxicity,transdermal transport and wound repair

Skin is widely used as a drug delivery route due to its easy access and the possibility of using relatively painless methods for the administration of bioactive molecules.However,the barrier properties of the skin,along with its multilayer structure,impose severe restrictions on drug transport and bioavailability.Thus,bioengineered models aimed at emulating the skin have been developed not only for optimizing the transdermal transport of different drugs and testing the safety and toxicity of substances but also for understanding the biological processes behind skin wounds.Even though in vivo research is often preferred to study biological processes involving the skin,in vitro and ex vivo strategies have been gaining increasing relevance in recent years.Indeed,there is a noticeably increasing adoption of in vitro and ex vivo methods by internationally accepted guidelines.Furthermore,microfluidic organ-on-a-chip devices are nowadays emerging as valuable tools for functional and behavioural skin emulation.Challenges in miniaturization,automation and reliability still need to be addressed in order to create skin models that can predict skin behaviour in a robust,high-throughput manner,while being compliant with regulatory issues,standards and guidelines.In this review,skin models for transdermal transport,wound repair and cutaneous toxicity will be discussed with a focus on high-throughput strategies.Novel microfluidic strategies driven by advancements in microfabrication technologies will also be revised as a way to improve the efficiency of existing models,both in terms of complexity and throughput.

Roots and rhizomes of wild Asparagus:Nutritional composition,bioactivity and nanoencapsulation of the most potent extract

The nutritional composition and bioactive properties of roots and rhizomes of Asparagus stipularis were evaluated.Antioxidant activity of extracts obtained by infusion was evaluated using free radicals scavenging and reducing power methods.Porcine liver primary cell was used to check the hepatotoxicity of infusions.Results revealed that Asparagus samples are likely a source of nutrients,such as dietary fibre and essential fatty acids.HPLC-DAD-ESI/MS characterization of infusions allowed the identification and quantitation of 7 phenolic compounds,all hydroxycinnamoyl derivatives,with caffeic acid as the most abundant.Roots infusion contained the highest amounts of these compounds.It also exhibited the highest antioxidant activity in all assays,with EC_(50) values of 0.44±0.01,0.98±0.03 and 0.64±0.01 mg/mL for DPPH,ABTS and FRAP assays,respectively,with no toxicity towards PLP2 primary cell cultures(GI_(50)>400μg/mL).PLGA nanoparticles loaded with root extract were prepared using solvent-evaporation double emulsion method.Nanoparticles size was about 260 nm and a polydispersity index around 0.1,with a zeta potential of about-36 mV,as well as a good encapsulation efficiency of approximately 83%.Their morphology was analysed by SEM and spherical polymeric nanoparticles with a smooth surface were observed.FTIR and DSC were also performed,which allowed corroborating the efficacy of the encapsulation and to confirm the production of a stable and robust system to load Asparagus extracts.The developed nanoparticles are expected to be used as delivery systems for bioactive compounds of A.stipularis and they could be used as an innovative dietary supplement.