Determination of in vitro antioxidant and UV-protecting activity of aqueous and ethanolic extracts from Galinsoga parviflora and Galinsoga quadriradiata herb

Plant Extracts as Skin Care and Therapeutic Agents

Natural ingredients have been used for centuries for skin treatment and care. Interest in the health effects of plants has recently increased due to their safety and applicability in the formulation of pharmaceuticals and cosmetics. Long-known plant materials as well as newly discovered ones are increasingly being used in natural products of plant origin. This review highlights the beneficial effects of plants and plant constituents on the skin, including moisturizing (e.g., Cannabis sativa, Hydrangea serrata, Pradosia mutisii and Carthamus tinctorius), anti-aging (e.g., Aegopodium podagraria, Euphorbia characias, Premna odorata and Warburgia salutaris), antimicrobial (e.g., Betula pendula and Epilobium angustifolium), antioxidant (e.g., Kadsura coccinea, Rosmarinus officinalis, Rubus idaeus and Spatholobus suberectus), anti-inflammatory (e.g., Antidesma thwaitesianum, Helianthus annuus, Oenanthe javanica, Penthorum chinense, Ranunculus bulumei and Zanthoxylum bungeanum), regenerative (e.g., Aloe vera, Angelica polymorpha, Digitaria ciliaris, Glycyrrihza glabra and Marantodes pumilum), wound healing (e.g., Agrimonia eupatoria, Astragalus floccosus, Bursera morelensis, Jatropha neopauciflora and Sapindus mukorossi), photoprotective (e.g., Astragalus gombiformis, Calea fruticose, Euphorbia characias and Posoqueria latifolia) and anti-tyrosinase activity (e.g., Aerva lanata, Bruguiera gymnorhiza, Dodonaea viscosa, Lonicera japonica and Schisandra chinensis), as well as their role as excipients in cosmetics (coloring (e.g., Beta vulgaris, Centaurea cyanus, Hibiscus sabdariffa and Rubia tinctiorum), protective and aromatic agents (e.g., Hyssopus officinalis, Melaleuca alternifolia, Pelargonium graveolens and Verbena officinalis)).

Galinsoga parviflora (Cav.): A comprehensive review on ethnomedicinal, phytochemical and pharmacological studies

Galinsoga parviflora (Cav.) is a member of the Asteraceae family traditionally used for treatment of various ailments such as malaria, flu, cold, colorectal cancer, liver problems and inflammation. The medicinal properties of G. parviflora are due to the presence of various secondary metabolites including flavonoids, saponins, terpenoids and tannins. The literature survey revealed that G. parviflora possesses several pharmacological properties such as antibacterial, antifungal, antioxidant and antidiabetic. This review systematically discusses the potential of G. parviflora for managing medical conditions. The information is collected from various online databases such as Google Scholar, ScienceDirect, Springer, Web of Science, Plant of the World Online and PubMed. Among other information provided in this review, ethnomedicinal uses, phytochemistry and pharmacological activities are discussed extensively. Additonally, the potential benefits, challenges and future opportunities are presented.

Plant Secondary Metabolites against Skin Photodamage: Mexican Plants, a Potential Source of UV-Radiation Protectant Molecules

Human skin works as a barrier against the adverse effects of environmental agents, including ultraviolet radiation (UVR). Exposure to UVR is associated with a variety of harmful effects on the skin, and it is one of the most common health concerns. Solar UVR constitutes the major etiological factor in the development of cutaneous malignancy. However, more than 90% of skin cancer cases could be avoided with appropriate preventive measures such as regular sunscreen use. Plants, constantly irradiated by sunlight, are able to synthesize specialized molecules to fight against UVR damage. Phenolic compounds, alkaloids and carotenoids constitute the major plant secondary metabolism compounds with relevant UVR protection activities. Hence, plants are an important source of molecules used to avoid UVR damage, reduce photoaging and prevent skin cancers and related illnesses. Due to its significance, we reviewed the main plant secondary metabolites related to UVR protection and its reported mechanisms. In addition, we summarized the research in Mexican plants related to UV protection. We presented the most studied Mexican plants and the photoprotective molecules found in them. Additionally, we analyzed the studies conducted to elucidate the mechanism of photoprotection of those molecules and their potential use as ingredients in sunscreen formulas.

Antioxidant Activity of Spiranthes sinensis and Its Protective Effect against UVB-Induced Skin Fibroblast Damage

Spiranthes sinensis (S. sinensis), a species of orchid, is a well-known herb medicine used to treat disorders such as stomachache, diabetes, shingles, and certain inflammatory diseases. Presently, the antioxidant activity of S. sinensis as well as its protective effect on UVB-induced skin injury are unclear. In this study, S. sinensis was extracted with boiling water or 75% (v/v) ethanol, and then its antioxidant composition and antioxidant activity were determined. The protective effects of S. sinensis against UVB-induced damage in human skin fibroblasts (CCD-966SK) were also investigated. Our data showed that the extraction yield of boiling water was higher than that of 75% ethanol. However, compared to the aqueous extracts, the ethanol extracts not only had higher phenolic, flavonoid, and condensed tannin contents, but also exhibited higher free radical scavenging activity, higher reducing power, and higher ferrous ion-chelating capacity. When fibroblasts were pre-cultured with the water or ethanol extracts of S. sinensis (1500 μg/mL) for 24 h before applying UVB irradiation, the S. sinensis extracts restored 17% to 27% of cell viability compared to a control only irradiated with UVB. Overall, our study suggests that S. sinensis extracts can be used as effective antioxidants and have the potential to protect skin fibroblasts from UVB irradiation.

Ultraviolet A protective potential of plant extracts and phytochemicals

Chronic exposure to solar radiation is related to an increased incidence of various skin disorders, including premature skin aging and melanoma and non-melanoma skin cancers. Ultraviolet (UV) photons in particular are responsible for skin damage. Solar UV photons mainly belong to UVA wavebands, however UVA radiation has been mostly ignored for a long time. At the cellular level, UVA photons mainly provoke indirect oxidative damage to biomolecules via the massive generation of unstable and highly reactive compounds. Human skin has several effective mechanisms that forestall, repair and eliminate damage caused by solar radiation. Regardless, some damage persists and can accumulate with chronic exposure. Therefore, conscious protection against solar radiation (UVB+UVA) is necessary. Besides traditional types of photoprotection such as sunscreen use, new strategies are being searched for and developed. One very popular protective strategy is the application of phytochemicals as active ingredients of photoprotection preparations instead of synthetic chemicals. Phytochemicals usually possess additional biological activities besides absorbing the energy of photons, and those properties (e.g. antioxidant, anti-inflammatory) magnify the protective potential of phytochemicals and extracts. Therefore, compounds of natural origin are in the interest of researchers as well as developers. In this review, only studies on UVA protection with well-documented experimental conditions are summarized. This article includes 17 well standardized plant extracts (Camellia sinensis (L.) Kuntze, Silybum marianum L. Gaertn., Punica granatum L., Polypodium aureum L., Vaccinium myrtillus L., Lonicera caerulea L., Thymus vulgaris L., Opuntia ficus-indica (L.) Mill., Morinda citrifolia L., Aloe vera (L.) Burm.f., Oenothera paradoxa Hudziok, Galinsoga parviflora Cav., Galinsoga quadriradiata Ruiz et Pavón, Hippophae rhamnoides L., Cola acuminata Schott & Endl., Theobroma cacao L. and Amaranthus cruentus L.) and 26 phytochemicals.

Characterization of the complete chloroplast genome sequence of Galinsoga parviflora and its phylogenetic implications

Galinsoga parviflora is an invasive weed in southwest of Chinese agricultural systems and commonly used as medicine and food. In this study, the complete chloroplast genome of the G. parviflora was assembled from the whole genome Illumina sequencing data. The circular genome is 151,811 bp in size, which composed of one large single-copy (LSC) and one small single-copy (SSC) regions of 83,594 bp and 18,141 bp, respectively, and separated by a pair of inverted repeat (IR) regions of 25,038 bp each. It encodes a total of 113 gene species (80 protein-coding, 29 tRNA, and four rRNA species), in which 19 of them with double copies. The overall GC content is 37.7% while the GC content of the LSC, SSC, and IR regions are 35.8%, 31.3%, and 43.1%, separately. Phylogenetic analysis indicated that Galinsoga parviflora was closely related to Galinsoga quadriradiata.

Caffeic acid derivatives isolated from Galinsoga parviflora herb protected human dermal fibroblasts from UVA-radiation

BACKGROUND

Among solar radiation, ultraviolet light is the most harmful for the skin, because of intracellular reactive oxygen species formation, leading to oxidative stress, cell damage and apoptosis. Crucial role in skin protection against oxidative stress play antioxidant enzymes regulated by Nrf2 transcription factor. Some plant-derived polyphenols are known to protect skin fibroblasts against UV through induction of Nrf2-dependent antioxidant genes expression.

PURPOSE

We previously found out that water extracts from Galinsoga sp. herb protected human dermal fibroblasts against UVA-induced oxidative stress and apoptosis. However, which compounds were responsible for such protective action remained unclear. Here, we investigated photoprotective potential and mechanism of action of two main isolated compounds, 2,3,5(2,4,5)-tricaffeoylaltraric acid and 2,4(3,5)-dicaffeoylglucaric acid, on human dermal fibroblasts (NHDF).

STUDY DESIGN/METHODS

NHDF cells were pretreated with tested compounds (6.25-50 µM) and irradiated with UVA (25 J/cm²). Intracellular ROS and GSH level, cell viability, cell membrane integrity and apoptosis were measured. HO-1 protein expression and Nrf2 transcription factor activation were also assessed.

RESULTS

Cells pretreated with tested compounds prior to UVA showed inhibition of intracellular ROS formation and increase of GSH level. Significant increase of cell viability was also observed, as well as decrease of LDH release and a the rate of apoptotic cells in comparison to untreated cells. Furthermore, tested compounds increased HO-1 expression and activated the Nrf2 transcription factor in NHDF cells.

CONCLUSION

Present study demonstrated that caffeic acid derivatives present in Galinsoga parviflora herb, in particular tricaffeoylaltraric acid may protect dermal fibroblasts against UVA-induced oxidative stress through activation of intracellular antioxidative system. Such caffeic acid derivatives are bioactive compounds which might prevent UV-induced photoageing and photocarcinogenesis.

Defense potential of secondary metabolites in medicinal plants under UV-B stress

Ultraviolet-B (UV-B) radiation has, for many decades now, been widely studied with respect to its consequences on plant and animal health. Though according to NASA, the ozone hole is on its way to recovery, it will still be a considerable time before UV-B levels reach pre-industrial limits. Thus, for the present, excessive UV-B reaching the Earth is a cause for concern, and UV-B related human ailments are on the rise. Plants produce various secondary metabolites as one of the defense strategies under UV-B. They provide photoprotection via their UV-B screening effects and by quenching the reactive oxygen- and nitrogen species produced under UV-B influence. These properties of plant secondary metabolites (PSMs) are being increasingly recognized and made use of in sunscreens and cosmetics, and pharma- and nutraceuticals are gradually becoming a part of the regular diet. Secondary metabolites derived from medicinal plants (alkaloids, terpenoids, and phenolics) are a source of pharmaceuticals, nutraceuticals, as well as more rigorously tested and regulated drugs. These metabolites have been implicated in providing protection not only to plants under the influence of UV-B, but also to animals/animal cell lines, when the innate defenses in the latter are not adequate under UV-B-induced damage. The present review focuses on the defense potential of secondary metabolites derived from medicinal plants in both plants and animals. In plants, the concentrations of the alkaloids, terpenes/terpenoids, and phenolics have been discussed under UV-B irradiation as well as the fate of the genes and enzymes involved in their biosynthetic pathways. Their role in providing protection to animal models subjected to UV-B has been subsequently elucidated. Finally, we discuss the possible futuristic scenarios and implications for plant, animal, and human health pertaining to the defense potential of these secondary metabolites under UV-B radiation-mediated damages.

High efficacy of (Z)-γ-bisabolene from the essential oil of Galinsoga parviflora (Asteraceae) as larvicide and oviposition deterrent against six mosquito vectors

The eco-friendly management of mosquitoes with novel and effective larvicides and oviposition deterrents is a crucial challenge to prevent outbreaks of mosquito-borne diseases. However, most of the herbal formulations tested in these years showed LC₅₀ values higher of 40 ppm, and significant oviposition deterrent activity only when tested at relatively higher doses (> 50 μg/ml). Herein, we studied the chemical composition of the Galinsoga parviflora essential oil (EO). This plant is an annual herb native to South America naturalized all over the world. We tested the EO larvicidal and oviposition deterrent action on 6 mosquito species. Totally 37 compounds were identified in the EO of G. parviflora by GC and GC-MS analyses. The major constituent was (Z)-γ-bisabolene (38.9%). The G. parviflora EO and (Z)-γ-bisabolene showed acute toxicity on An. stephensi (LC₅₀ = 31.04 and 2.04 μg/ml, respectively), Ae. aegypti (LC₅₀ = 34.22 and 2.26 μg/ml, respectively), Cx. quinquefasciatus (LC₅₀ = 37.10 and 2.47 μg/ml, respectively), An. subpictus (LC₅₀ = 40.97 and 4.09 μg/ml, respectively), Ae. albopictus (LC₅₀ = 45.55 and 4.50 μg/ml, respectively) and Cx. tritaeniorhynchus (LC₅₀ = 49.56 and 4.87 μg/ml, respectively) larvae. Furthermore, the oviposition deterrent potential of the G. parviflora EO and (Z)-γ-bisabolene was studied on six mosquito vectors, showing that 25 μg/ml of (Z)-γ-bisabolene led to an Oviposition Activity Index lower of - 0.79 in all tested mosquito vectors. Overall, all larvicidal LC₅₀ values estimated for (Z)-γ-bisabolene were lower than 5 μg/ml. This result far encompasses current evidences of toxicity reported for the large majority of botanical products currently tested against mosquito young instars, allowing us to propose this compound as an highly effective mosquito larvicide and oviposition deterrent.

Herbal extracts, lichens and biomolecules as natural photo-protection alternatives to synthetic UV filters. A systematic review

Besides the unquestionable positive effects of solar exposure for human health, UV rays have been widely investigated for toxicology aspects related to excessive UVB and UVA doses, which involve sunburns, skin aging, DNA skin damage and tumorigenesis. At present, synthetic and mineral sunscreens are used to protect against these damages but several natural molecules can provide UV protection, including also synergic effect or enhanced photo stability. Although a large number of herbal extracts and plant origin molecules can deserve potential applications, most of the study reported utilizes different method and different strategies of investigation, making thus difficult to understand the real versus claimed potential. This is possibly one of the reasons why, beside the large body of literature there are no officially approved natural commercial sun-filter but a consistent number of commercially available solar products (sunscreen) on the market that contain herbal derivatives. In this review we have evaluated the papers appeared in the last 15years and we have critically collected the most significant data. Several databases, namely Scifinder, Pubmed, Google Scholar, ISI-Web of Science and Scopus, were used as literature sources; excluding patents and symposium or congress papers. Only articles in the English language have been selected. New formulation, new skin delivery systems, skin penetration enhancers and boosters are most likely the next frontier of investigation in order to better understand the role of whole herbal extracts in exerting their photo protective activity.