Glycyrrhizae radix et rhizoma processing ameliorates adverse reactions of polygalae radix in zebra fish and rabbit models.

ETHNOPHARMACOLOGICAL RELEVANCE: Polygala tenuifilia Willd (Polygalaceae), a traditional Chinese medicine, has been used for a long time to treat various illnesses with serious adverse reactions. Glycyrrhizae radix et rhizoma processing is generally used to reduce the adverse reactions. AIM OF THE STUDY: The aim of this study was to validate the irritation caused by raw Polygalaceae (RPA), to investigate whether processed Polygalaceae (PGA) was less irritating, and to screen and validate irritant properties of virgaureagenin G (polygala acid, PA), 3,6'-disinapoylsucrose (DSS), Tenuifolia (TEN) and polygalaxanthone III (POL), which had pharmacologically active in Polygalaceae. Zebrafish model, Draize test and High-Performance Liquid Chromatography (HPLC) were utilized to achieve the aim. MATERIALS AND METHODS: Scanning Electron Microscopy (SEM) and optical microscope were used to determine the presence of calcium oxalate needle crystal in RPA and PGA. Zebrafish egg spinning changes and zebrafish embryo behavior were used for irritation validation, irritation comparison and irritant screening. For additional evidence, the Draize test, HE staining of rabbit eyes and ELISA kit were used. Finally, changes in the composition of RPA and PGA were investigated using HPLC. RESULTS: SEM and optical microscopy revealed no calcium oxalate needle crystals in Polygalaceae. RPA, PGA, PA and DSS were able to accelerate the spinning of zebrafish eggs and the movement of embryos, while TEN and POL were not. RPA, PGA, DSS and PA may cause rabbit eyes to become hyperemic and swollen, resulting in damage to the iris, cornea and conjunctiva and increased levels of interleukin-6 (IL-6) and interleukin-10 (IL-10). Comparatively, the effects caused by PGA were less severe than those caused by RPA. In addition, compared to RPA, PGA had lower levels of DSS and PA. CONCLUSIONS: RPA, PGA, DSS, and PA were irritating. However, processing and curing could reduce the irritation by reducing the levels of DSS and PA. DSS and PA could be two potential irritants of Polygalaceae.

Skin irritation assessment and potential mechanism of Capparis spinosa L. fruits.

ETHNOPHARMACOLOGICAL RELEVANCE: In China, Capparis spinosa L. fruits (CSF) are often used topically in Uyghur folk medicine in treating rheumatic diseases with remarkable efficacy. However, it has noticed severe skin irritation after a short time application with high dose of CSF, which limited long-term clinical use. To date, there is almost no research related to skin irritation of CSF. AIM OF THE STUDY: This study was intended to perform the first systematic assessment of morphological and histological changes in skin after stimulation with CSF. Furthermore, potential irritant components in CSF and related mechanisms were explored by in vitro transdermal techniques, network pharmacology, molecular docking, and experimental validation. MATERIALS AND METHODS: Skin changes after single and multiple stimulations with CSF were observed and subjected to skin irritation response scoring, irritation strength assessment, and histopathological analysis. In addition, in vitro transdermal technology, liquid chromatography-mass spectrometry (LC-MS) method, network pharmacology, molecular docking, and experimental validation were used to further exploit underlying skin irritant components and possible mechanisms of action. RESULTS: CSF induced significant morphological (erythema and edema) and histological (epidermal thickening and inflammatory infiltration) changes in skin of mice, which were similar to the clinical presentation of irritation contact dermatitis (ICD). The ethyl acetate fraction of CSF (CFEAF) was the main source of CSF-induced skin irritation. Kaempferol, flazin, and gallic acid were potential major irritant compounds. Moreover, CFEAF, kaempferol, flazin, and gallic acid could increase the levels of pro-inflammatory cytokines tumor necrosis factor-alpha (TNF-α), intercellular adhesion molecule-1 (ICAM-1), and interleukin-17A (IL-17A) to promote skin inflammation. The potential mechanism of CSF-induced skin irritation may be activation of the nuclear factor kappa-B (NF-κB) signaling pathway, including phosphorylation of NF-κB p65 (p65) and nuclear factor-kappa B inhibitor alpha (IκBα). CONCLUSION: Kaempferol, flazin, and gallic acid are potential skin irritant components from CSF. Altogether, they induce skin irritation responses through promoting the release of the inflammatory factors TNF-α and ICAM-1, as well as activating the NF-κB signaling pathway. In addition, IL-17A may be an important pro-inflammatory factor in skin irritation.

The frontline of alternatives to animal testing: novel in vitro skin model application in drug development and evaluation.

The FDA Modernization Act 2.0 has brought nonclinical drug evaluation into a new era. In vitro models are widely used and play an important role in modern drug development and evaluation, including early candidate drug screening and preclinical drug efficacy and toxicity assessment. Driven by regulatory steering and facilitated by well-defined physiology, novel in vitro skin models are emerging rapidly, becoming the most advanced area in alternative testing research. The revolutionary technologies bring us many in vitro skin models, either laboratory-developed or commercially available, which were all built to emulate the structure of the natural skin to recapitulate the skin's physiological function and particular skin pathology. During the model development, how to achieve balance among complexity, accessibility, capability, and cost-effectiveness remains the core challenge for researchers. This review attempts to introduce the existing in vitro skin models, align them on different dimensions, such as structural complexity, functional maturity, and screening throughput, and provide an update on their current application in various scenarios within the scope of chemical testing and drug development, including testing in genotoxicity, phototoxicity, skin sensitization, corrosion/irritation. Overall, the review will summarize a general strategy for in vitro skin model to enhance future model invention, application, and translation in drug development and evaluation.

Perceptions of skincare ingredients and product labels in pediatric eczema care.

Educating pediatric eczema patients and caregivers on appropriate product selection and avoidance of common irritants or allergens is a crucial aspect of eczema management. This study surveyed 80 pediatric caregivers in an academic pediatric dermatology clinic to assess influential factors in caregivers' selection of pediatric eczema-care products and identify ways to improve patient counseling on appropriate product selection and avoidance of common irritants or allergens. Caregivers frequently reported positive perceptions of commonly recommended ingredients for eczema but had inconsistent perceptions of fragrant plant oils and extracts, regardless of previous counseling on fragrance avoidance. These findings demonstrate uncertainty and misperceptions perpetuated by product labeling and a need for improved counseling strategies for avoiding fragrance and excessive product costs.

Effect of acetone fraction of Ottelia alismoides on the G2/M cell cycle arrest and apoptosis in the human carcinoma cell lines.

ETHNOPHARMACOLOGICAL RELEVANCE: The North-eastern parts of India have immense therapeutic floras, Ottelia alismoides is an aquatic plant that has been in use for a long time in traditional medicine for treating diseases like cancer, tuberculosis, diabetes, febrifuge, hemorrhoids, and rubefacient. In lung and skin carcinoma cells with a high rate of proliferation and metastasis including drug resistance and non-specific target activity, generates important challenges towards their treatment strategy. Thus, finding novel therapeutic targets to treat lung and skin cancer progression is essential to enhance the patients' survival with treatment. AIM OF THE STUDY: The purpose of this study was to evaluate the apoptotic potential of acetone extract of O. alismoides (L.) Pers. (OA-AC) and to identify the compounds responsible for this effect, HRLC-MS-QTOF analysis of the extract has been undertaken along with in-silico molecular docking analysis of the identified compounds. MATERIALS AND METHODS: A549 and A431 cells were treated with acetone extract of O. alismoides (OA-AC) at 24 h and 48 h exposure and cell cycle phase distribution was evaluated and also apoptosis induction activity was evaluated by OA-EtBr staining and Mitochondrial outer membrane potential assay. Western blotting was performed for the evaluation of apoptotic protein expression. At last, the HR-LCMS of OA-AC was analyzed to identify the compounds responsible for the apoptotic activity of the extract. RESULTS: The cell cycle phase distribution analysis in A549 and A431 cells at 24hrs exposure with 10 µg/mL and 25 µg/mL of OA-AC showed a potent arrest or blockage at the G2/M phase of the cell cycle with reduced expression of cyclin B and p-Cdc2. At 48 h exposure, apoptosis was observed in these cancer cells with elevated expression of Bax, p21 and cleaved caspase 3 and reduced expression of the Bcl2. CONCLUSION: AO-EtBr staining of these cancer cells reveals that the death induced by OA-AC was apoptotic in nature with depolarization of mitochondrial membrane due to loss or damage of the mitochondrial membrane. The HRLC-MS-QTOF analysis of OA-AC depicted 14 major isolable compounds and molecular docking analysis displayed 4 compounds that might act as an inhibitor of cyclin B for G2/M phase arrest that leads to apoptotic induction in the cells.

Hypersensitivity Reactions to Homemade Topical Preparations.

Homemade topical preparations are becoming increasingly popular due to the widespread belief that herbal and natural products are a safer and better option in the treatment of various conditions. However, homemade topical preparations can precipitate allergic and irritant reactions, depending on the herbal composition of the preparation. Hypersensitivity reactions to such preparations range from contact allergic dermatitis, contact irritant dermatitis, contact urticaria, toxic reaction, photosensitivity, and phototoxic reaction. In Europe, and especially in the Mediterranean area, medicinal herbs from the Compositae family and aromatic Mediterranean herbs are most frequently used in the formulation of topical preparations. Although plants are regarded as strong sensitizers, the number of reported cases of hypersensitivity reactions is relatively small. The problems are limitations in diagnostics due to the lack of necessary patch test substances and the danger of active sensitization during testing. Caution is required in patients prone to allergies and those with existing dermatoses, who should be advised to use registered preparations. The first step in management is cessation of exposure, followed by implementation of topical corticosteroids. Systemic corticosteroid therapy is reserved for more severe cases.

Treatment of sensitive skin by short-wave radiofrequency combined with intense pulsed light.

BACKGROUND: Sensitive skin is a widespread dermatologic condition, and no optimal treatments have been established so far. OBJECTIVE: To investigated the efficacy and safety of the combined therapy of short-wave radiofrequency (SWRF) and intense pulsed light (IPL) in improving transepidermal water loss (TEWL) and facial erythema in sensitive skin patients. METHODS: Twenty-two patients with sensitive skin received the SWRF treatment once per week for 4 weeks and IPL treatment once. Digital photographs and three-dimensional images were taken at each follow-up. The clinical efficacy was evaluated by the improvement of sensitive scale-10 including irritant symptoms and facial erythema. In addition, erythema area and TEWL values were measured. RESULTS: All patients showed subjective and objective improvement in irritant sensations and facial erythema after treatment. The TEWL values decreased from 20.29 ± 5.97 g·h-1 ·m-2 at baseline to 14.70 ± 6.02 g·h-1 ·m-2 after SWRF treatment and 13.78 ± 4.70 g·h-1 ·m-2 after combined therapy (p = 0.000). The clearance of the erythema area was statistically significant, with 14.05% ± 5.71% at baseline, 9.38% ± 4.08% after SWRF treatment, and 5.73% ± 2.79% after combined therapy (p = 0.000). No adverse events were observed. CONCLUSIONS: The combination of SWRF with IPL was effective in relieving skin irritant sensations and facial erythema of sensitive skin by repairing skin barrier function.

[Irritant toxicity and lectin content of different processed products of Pinelliae Rhizoma].

The present study aims to investigate the correlation between irritant toxicity variation and lectin content variation during the processing of Pinelliae Rhizoma products and to explore the feasibility of Western blot as a method for the detection of lectin. We processed Pinelliae Rhizoma Praeparatum Cum Alumine, Pinelliae Rhizoma Praeparatum, and Pinelliae Rhizoma Praeparatumcum Zingibere et Alumine to different degrees and then analyzed their irritant toxicity via Draize rabbit eye test. Western blot was employed to determine the lectin content in Pinelliae Rhizoma products processed with different methods. The correlation between toxicity variation and lectin content variation was then analyzed. Different decoction pieces of Pinelliae Rhizoma were collected for the determination of lectin content. The three processed products of Pinelliae Rhizoma showed gradually decreased toxicity and lectin content as the processing continued. The decreasing trend of lectin content was consistent with that of irritant toxicity during processing, which indicated that the change in lectin content could reflect the trend of irritant toxicity. No band of lectin appeared in the Western blot of processed products of Pinelliae Rhizoma, which suggested that western blotting can be used for the detection of toxic lectin in the processed products of Pinelliae Rhizoma. Lectin should not be detected in the Pinelliae Rhizoma products processed according to the methods in the Chinese Pharmacopoeia.

The user safety assessment of a selenized yeast feed additive.

Purpose: Of the several selenized yeasts authorised for use as feed additives in the EU, Saccharomyces cerevisiae CNCM I-3060 inactivated' (Sel-Plex®), was the first to be approved for use, in 2006. The additive has a concentration of selenium between 2000 and 2400 mg/kg and a selenomethionine content greater than 63%. Previous toxicological and safety studies have shown Sel-Plex® to be safe for use for target animal species, consumers, users and the environment. A new formulation of Sel-Plex® was recently developed however, with a minimum selenium content of 3000 mg/kg. The increase in selenium in this product, Sel-Plex® 3000, presented the need to assess the risk for workers and users and to establish if there would be any eye and/or skin irritancy and skin sensitisation effects associated with the product. The purpose of this paper is to present the methodology and results of the user safety skin and eye studies performed on Sel-Plex® 3000.Materials & Methods: In vitro skin and eye models were used to assess skin and eye irritancy, while skin sensitisation was examined using an in vivo method. The acute eye irritation was evaluated using a Reconstructed human Cornea-like Epithelium (RhCE) model, which followed the OECD guideline 492. The skin irritation was assessed based on its ability to induce cell death in a commercial reconstructed human epidermis (RhE) model (EPISKIN™) according to the OECD Guideline No. 439. The skin sensitising potential was evaluated in the Guinea pig in line with OECD Guideline 406, and measured the extent and degree of skin reaction to a challenge exposure following previous topical exposure of a substance on the skin.Results: The skin and eye irritation test results showed that Sel-Plex® 3000 was a non-irritant in both cases. The skin sensitisation study showed that the additive did not generate a sensitisation response in the guinea pig and should not be considered a skin sensitiser.Conclusion: These results indicate that Sel-Plex® 3000 is safe to use for workers in an industrial setting when handling the product and the studies may be further used to support regulatory compliance in respective markets.

Vitamin D supplementation in patients with atopic dermatitis, chronic urticaria and contact irritant and allergic dermatitis - possible improvement without risk.

Abstract.

Enhanced Excito-Repellency of Binary Mixtures of Plant-Based Mosquito Repellents Against Culex quinquefasciatus Say (Diptera: Culicidae), a Night Biting Mosquito Species.

Efficacies of essential oils (EOs) of Vetiveria zizanioides (L.) Nash. (Poales: Poaceae) (VZ EO), Cananga odorata (Lam) Hook. F. & Thomson (Magnoliales: Annonaceae) (CO EO), and crude extract (CE) of Andrographis paniculata (Burm.F.) Wall ex. Nees (Lamiales: Acanthaceae) (AP CE), against laboratory (lab) and field strains of Culex quinquefasciatus Say were investigated. Irritant and repellent activities of individual and binary mixtures of plant extracts were compared with N,N-diethyl-m-toluamide (DEET) using an excito-repellency system. The irritant activity (direct tarsal contact), the mean percent escape response of VZ EO (91.67%, 83.33%), and CO EO (80%, 88.33%) were not significantly different compared with DEET (88.33%, 95%) against lab and field strains, respectively. Similarly, irritant responses in combinations (1:1 and 1:2, v:v) of either VZ EO or CO EO with AP CE were not significantly different from DEET against both strains (P > 0.001). The repellent activity (no tarsal contact), the mean percent escape response of VZ EO (68.33%), CO EO (61.67%), and VZ EO+AP CE (1:1, v:v) (81.67%) against lab strain and CO EO (85%) against field strain were not significantly different from that of DEET (P > 0.001). Interestingly, the greatest contact irritancy of VZ EO+AP CE (1:1, v:v) (96.67%) (P = 0.0026) and a stronger repellency response of CO EO (85%) (P = 0.0055) produced significantly different patterns of escape response compared with DEET against both lab and field strains, respectively. The EOs of VZ EO and CO EO or their mixture with AP CE showed potential as plant-based active ingredients for mosquito repellents. In addition, the major chemical constituents of VZ EO were ß-vetivone (6.4%), khusimol (2.96%), and α-vetivone (2.94%) by gas chromatograpy-mass spectrometry.

Ascorbic acid specifically reduces the misclassification of nonirritating reactive chemicals in the OptiSafe™ macromolecular eye irritation test.

Recently, we showed that the addition of physiological concentrations of ascorbic acid, a tear antioxidant, to the OptiSafe™ macromolecular eye irritation test reduced the false-positive (FP) rate for chemicals that had reactive chemistries, leading to the formation of reactive oxygen species (ROS) and molecular crosslinking. The purpose of the current study was to 1) increase the number of chemicals tested to comprehensibly determine whether the antioxidant-associated reduction in OD is specific to FP chemicals associated with ROS chemistries and 2) determine whether the addition of antioxidants interferes with the detection of true positive (TP) and true negative (TN) ocular irritants. We report that when ascorbic acid is added to the test reagents, retesting of FP chemicals with reactive chemistries show significantly reduced OD values (P < 0.05). Importantly, ascorbic acid had no significant effect on the OD values of TP or TN chemicals regardless of chemical reactivity. These findings suggest that supplementation of ascorbic acid in alternative ocular irritation tests may help improve the detection of TN for those commonly misclassified reactive chemicals.

Contact Dermatitis of the Hands: Is It Irritant or Allergic?

Hand contact dermatitis is common, and irritant contact dermatitis (ICD) is more likely than allergic contact dermatitis (ACD) in both occupational and nonoccupational settings. Irritant contact dermatitis can have acute and chronic presentations, and hand hygiene products can contribute. The most common relevant hand contact allergens in North American patch test populations are methylisothiazolinone (MI), nickel, formaldehyde, quaternium-15, and fragrance mix I. In health care workers, rubber accelerators often are relevant as potential contact allergens. Clinically, it can be difficult to differentiate between ICD and ACD, and patch testing often is required for definitive diagnosis. When patch testing is indicated, supplemental allergen series in addition to a screening series often are needed. Management of hand contact dermatitis requires gentle skin care, avoidance of irritants and/ or allergens when appropriate, and prescription topical or systemic therapies or phototherapy when indicated.

Distribution, Ecology, Chemistry and Toxicology of Plant Stinging Hairs.

Plant stinging hairs have fascinated humans for time immemorial. True stinging hairs are highly specialized plant structures that are able to inject a physiologically active liquid into the skin and can be differentiated from irritant hairs (causing mechanical damage only). Stinging hairs can be classified into two basic types: Urtica-type stinging hairs with the classical "hypodermic syringe" mechanism expelling only liquid, and Tragia-type stinging hairs expelling a liquid together with a sharp crystal. In total, there are some 650 plant species with stinging hairs across five remotely related plant families (i.e., belonging to different plant orders). The family Urticaceae (order Rosales) includes a total of ca. 150 stinging representatives, amongst them the well-known stinging nettles (genus Urtica). There are also some 200 stinging species in Loasaceae (order Cornales), ca. 250 stinging species in Euphorbiaceae (order Malphigiales), a handful of species in Namaceae (order Boraginales), and one in Caricaceae (order Brassicales). Stinging hairs are commonly found on most aerial parts of the plants, especially the stem and leaves, but sometimes also on flowers and fruits. The ecological role of stinging hairs in plants seems to be essentially defense against mammalian herbivores, while they appear to be essentially inefficient against invertebrate pests. Stinging plants are therefore frequent pasture weeds across different taxa and geographical zones. Stinging hairs are usually combined with additional chemical and/or mechanical defenses in plants and are not a standalone mechanism. The physiological effects of stinging hairs on humans vary widely between stinging plants and range from a slight itch, skin rash (urticaria), and oedema to sharp pain and even serious neurological disorders such as neuropathy. Numerous studies have attempted to elucidate the chemical basis of the physiological effects. Since the middle of the 20th century, neurotransmitters (acetylcholine, histamine, serotonin) have been repeatedly detected in stinging hairs of Urticaceae, but recent analyses of Loasaceae stinging hair fluids revealed high variability in their composition and content of neurotransmitters. These substances can explain some of the physiological effects of stinging hairs, but fail to completely explain neuropathic effects, pointing to some yet unidentified neurotoxin. Inorganic ions (e.g., potassium) are detected in stinging hairs and could have synergistic effects. Very recently, ultrastable miniproteins dubbed "gympietides" have been reported from two species of Dendrocnide, arguably the most violently stinging plant. Gympietides are shown to be highly neurotoxic, providing a convincing explanation for Dendrocnide toxicity. For the roughly 648 remaining stinging plant species, similarly convincing data on toxicity are still lacking.

Topical hydrogel containing Achyrocline satureioides oily extract (free and nanocapsule) has anti-inflammatory effects and thereby minimizes irritant contact dermatitis.

Inflammatory dermatoses are prevalent worldwide, with impacts on the quality of life of patients and their families. The aim of this study was to determine the anti-inflammatory effects of Achyrocline satureioides oily extracts and nanocapsules on the skin using a mouse model of irritant contact dermatitis induced by croton oil, and a skin inflammation model induced by ultraviolet B (UVB) radiation. The mice were treated with 15 mg/ear oily extract (HG-OLAS) or nanocapsules (HG-NCAS) of A. satureioides incorporated into Carbopol® 940 hydrogels. We found that HG-OLAS and HG-NCAS formulations reduced ear edema in croton oil-induced lesions with maximum inhibitions of 54±7% and 74±3%, respectively. HG-OLAS and HG-NCAS formulations decreased ear edema induced by UVB radiation (0.5 J/cm2), with maximum inhibitions of 68±6% and 76±2% compared to the UVB radiation group, respectively. HG-OLAS and HG-NCAS modulated myeloperoxidase (MPO) activity after croton oil induction. Furthermore, croton oil and UVB radiation for 6 and 24 h, respectively, stimulated polymorphonuclear cells infiltration. The topical treatments reduced inflammatory processes, as shown by histological analysis. Together, the data suggest that topical application of A. satureioides oily extracts and nanocapsules produced antiedematogenic and anti-inflammatory effects. They constitute a compelling alternative for treatment of skin injuries.

The safety profile of Bald's eyesalve for the treatment of bacterial infections.

The rise in antimicrobial resistance has prompted the development of alternatives to combat bacterial infections. Bald's eyesalve, a remedy used in the Early Medieval period, has previously been shown to have efficacy against Staphylococcus aureus in in vitro and in vivo models of chronic wounds. However, the safety profile of Bald's eyesalve has not yet been demonstrated, and this is vital before testing in humans. Here, we determined the safety potential of Bald's eyesalve using in vitro, ex vivo, and in vivo models representative of skin or eye infections. We also confirmed that Bald's eyesalve is active against an important eye pathogen, Neisseria gonorrhoeae. Low levels of cytotoxicity were observed in eyesalve-treated cell lines representative of skin and immune cells. Results from a bovine corneal opacity and permeability test demonstrated slight irritation to the cornea that resolved within 10 min. The slug mucosal irritation assay revealed that a low level of mucus was secreted by slugs indicating moderate mucosal irritation. We obtained promising results from mouse wound closure experiments; no visible signs of irritation or inflammation were observed. Our results suggest that Bald's eyesalve could be tested further on human volunteers to assess safety for topical application against bacterial infections.

Nutraceuticals as potential therapeutics for vesicant-induced pulmonary fibrosis.

Exposure to vesicants, including sulfur mustard and nitrogen mustard, causes damage to the epithelia of the respiratory tract and the lung. With time, this progresses to chronic disease, most notably, pulmonary fibrosis. The pathogenic process involves persistent inflammation and the release of cytotoxic oxidants, cytokines, chemokines, and profibrotic growth factors, which leads to the collapse of lung architecture, with fibrotic involution of the lung parenchyma. At present, there are no effective treatments available to combat this pathological process. Recently, much interest has focused on nutraceuticals, substances derived from plants, herbs, and fruits, that exert pleiotropic effects on inflammatory cells and parenchymal cells that may be useful in reducing fibrogenesis. Some promising results have been obtained with nutraceuticals in experimental animal models of inflammation-driven fibrosis. This review summarizes the current knowledge on the putative preventive/therapeutic efficacy of nutraceuticals in progressive pulmonary fibrosis, with a focus on their activity against inflammatory reactions and profibrotic cell differentiation.