Arnica L. genus (Asteraceae) comprises perennial herbs native to the temperate and boreal parts of the northern hemisphere. Arnica montana is the main species. It shows different biological activities, such as antioxidant, anti-inflammatory, antibacterial, antifungal, and antitumor effects. The Arnica formulations are mainly used for pain management. This systematic review is aimed at summarizing the studies focusing on the use of Arnica products on pain and inflammatory signs due to traumatic injuries related to sport and surgical interventions as well as to arthritis and other inflammatory conditions. Both phytotherapeutic and homeopathic formulations are taken into account. This paper only includes manuscripts published in mainstream journals. A literature search from Scopus, Web of Science, and PubMed databases has been carried out using a combination of the keywords “Arnica”, “trauma”, “sport”, “injury”, “injuries”, and “pain”. According to the search strategy and inclusion criteria for this study, 42 eligible papers, focusing on both Arnica alone and formulations containing a mixture of plant extracts, have been finally selected. This review critically discusses the in vitro, in vivo, and clinical studies dealing with Arnica products, reporting both positive and negative outcomes, thus providing perspectives for future research on the plant pharmacological potential.

Inflammatory bowel disease (IBD) is a group of complex chronic inflammatory conditions affecting the gastrointestinal tract. It is linked to a number of genetic and environmental factors able to perturb the immune-microbiome axis. Diet is the most investigated variable both for its role in the etiology of IBD and for its beneficial potential in the treatment of the symptoms. Dietary products may influence intestinal inflammation through different mechanisms of action, such as the modulation of inflammatory mediators, the alteration of gene expression, changes in gut permeability, and modifications in enteric flora composition. A consisting number of studies deal with the link between nutrition and microbial community, and particular attention is paid to plant-based foods. The effects of the dietary intake of different fruits have been investigated so far. This review aims to present the most recent studies concerning the beneficial potential of fruit consumption on human gut microbiota. Investigated plant species are described, and obtained results are presented and discussed in order to provide an overview of both in vitro and in vivo effects of fruits, their juices, and freeze-dried powders.

A lamellar lyotropic liquid crystal genistein-based formulation (LLC-Gen) was prepared in order to increase the aqueous solubility of the lipophilic phytocompound genistein. The formulation was applied locally, in a murine model of melanoma, with or without electroporation. The results demonstrated that, when the formulation was applied by electroporation, the tumors appeared later. During the 21 days of the experiment, the LLC-Gen formulation decreased the tumor volume, the amount of melanin and the degree of erythema, but when electroporation was applied, all these parameters indicated a better prognosis even (lower tumor volume, amount of melanin and degree of erythema). Although hematoxylin–eosin (HE) staining confirmed the above events, application of the LLC-Gen formulation by electroporation did not lead to a significant effect in terms of the serum concentrations of the protein S100B and serum neuron specific enolase (NSE), or the tissue expression of the platelet-derived growth factor receptor β (PDGFRβ) antibody.

Stilbenoids, a group of phytoalexin polyphenols produced by plants as a defence mechanism in response to stress conditions, are known for their anti-inflammatory potential. Pinosylvin, a naturally occurring molecule traditionally found in pinus trees, was here identified in Pinus nigra subsp. laricio var. calabrica from Southern Italy through HPLC analysis. Both this molecule and its well-known analogue resveratrol, the most famous wine polyphenol, were compared for their in vitro potential anti-inflammatory activity. Pinosylvin significantly inhibited the release of pro-inflammatory cytokines (TNF-α and IL-6) and NO mediator in LPS-stimulated RAW 264.7 cells. Moreover, its ability to inhibit the JAK/STAT signaling pathway was assessed: Western blot analyses showed a downregulation of both phosphorylated JAK2 and STAT3 proteins. Finally, in order to verify whether this biological activity could be attributed to a direct interaction of pinosylvin with JAK2, a molecular docking study was performed, confirming the capability of pinosylvin to bind the active site of the protein.

Glycyrrhiza glabra L. is a species widely spread all over the world, with a long tradition of use in folk medicine. Here, raw and hydrolyzed extracts obtained from roots collected in different geographical areas belonging to the Mediterranean basin were standardized as regards the amount of three main compounds: glycyrrhizin, the most abundant triterpene saponin of licorice, the 18β-glycyrrhetinic acid and the chalcone isoliquiritigenin. Raw and hydrolyzed extracts, as well as their pure single compounds, were investigated for their potential anti-inflammatory properties. The hydrolyzed extracts significantly reduced the production of pro-inflammatory cytokines such as TNF-α, IL-6, NO mediator in LPS-stimulated RAW 264.7 cells. Moreover, they were able to inhibit JAK2 and STAT3 phosphorylated proteins more than pure single standards tested at the same final concentrations, displaying a strength synergism of action. These findings suggest that G. glabra extracts and, more specifically, the hydrolyzed ones could represent interesting sources of potential anti-inflammatory agents able to inhibit the JAK/STAT signaling pathway.

Allium genus (Amaryllidaceae) is widely distributed in the Northern hemisphere. Some species, including garlic and onion, have been used since ancient times as both food ingredients and medicinal plants. Many reviews deal with the chemical constituents, particularly the typical sulfur compounds, as well as with Allium pharmacological properties, such as antimicrobial, anti-inflammatory, antioxidant, and cytotoxic activities. The bibliographic search performed in this review is mainly focused on the potential role of Allium species in inhibiting melanogenesis, which has been mainly assessed through the evaluation of the inhibitory properties on tyrosinase, the key enzyme in melanin biosynthesis. Two well established models for identifying potential skin-whitening agents have been used to assess the anti-melanogenic effects of Allium species, the mushroom tyrosinase and the murine melanoma B16 cell line. Here, a literature search from Scopus, Web of Science, and PubMed databases has been performed using the keywords “Allium”, “tyrosinase”, “anti-melanogenic”, and “melanogenesis”, combined by means of Boolean operators. Based on selected inclusion criteria, 32 eligible papers have been selected. The aim of this systematic review is to offer an overview of the species for which the ability to affect melanogenesis has been demonstrated to date, highlighting a new and emerging perspective on the potential therapeutic use of Allium species. The biological properties of isolated pure compounds and the negative outcomes have been also considered.