Phenol-induced in vivo oxidative stress in skin: evidence for enhanced free radical generation, thiol oxidation, and antioxidant depletion

Phytochemical fingerprinting of phytotoxins as a cutting-edge approach for unveiling nature's secrets in forensic science

The integration of phytochemistry into forensic science has emerged as a groundbreaking frontier, providing unprecedented insights into nature's secrets through the precise application of phytochemical fingerprinting of phytotoxins as a cutting-edge approach. This study explores the dynamic intersection of phytochemistry and forensic science, highlighting how the unique phytochemical profiles of toxic plants and their secondary metabolites, serve as distinctive markers for forensic investigations. By utilizing advanced techniques such as Ultra-High-Performance Liquid Chromatography (UHPLC) and High-Resolution Mass Spectrometry (HRMS), the detection and quantification of plant-derived are made more accurate in forensic contexts. Real-world case studies are presented to demonstrate the critical role of plant toxins in forensic outcomes and legal proceedings. The challenges, potential, and future prospects of integrating phytochemical fingerprinting of plant toxins into forensic science were discussed. This review aims to illuminate phytochemical fingerprinting of plant toxins as a promising tool to enhance the precision and depth of forensic analyses, offering new insights into the complex stories embedded in plant toxins.

Stachys byzantina K. Koch in the Treatment of Skin Inflammation: A Comprehensive Evaluation of Its Therapeutic Properties

Stachys byzantina is a plant widely cultivated for food and medicinal purposes. Stachys species have been reported as anti-inflammatory, antibacterial, anxiolytic, and antinephritic agents. This study aimed to evaluate the anti-inflammatory potential of the ethanolic extract (EE) from the aerial parts of S. byzantina and its most promising fraction in models of acute and chronic inflammation, including a psoriasis-like mouse model. The EE was fractionated into hexane (HF), dichloromethane (DF), ethyl acetate (AF), and hydroalcoholic (HD) fractions. Screening for anti-inflammatory activity based on nitric oxide inhibition (IC50 μg/mL: HF 24.29 ± 5.87, EE 176.45 ± 18.65), hydroxyl radical scavenging (HF 3.89 ± 0.61, EE 6.38 ± 2.25), β-carotene/linoleic acid assay (HF 10.13 ± 3.81, EE 25.64 ± 2.12), and ORAC identified HF as the most active fraction. Topical application of HF effectively reduced croton oil- and phenol-induced ear edema in mice, with no statistical difference to the reference drugs. A formulation containing HF showed significant activity in the imiquimod-induced psoriasis model, reducing pro-inflammatory cytokines and nitric oxide production in macrophages, with no cytotoxicity to skin cells. Phytochemical analysis of HF revealed the presence of terpenes, steroids (491.68 ± 4.75 mg/g), phenols (34.30 ± 4.96 mg/g), flavonoids (151.77 ± 6.66 mg/g), and α-tocopherol, which was identified and quantified by HPLC-UV analysis (10.56 ± 0.97 mg/g of HF). These findings highlight the therapeutic potential of S. byzantina for skin inflammation, particularly contact dermatitis and psoriasis, encouraging further studies, including in human volunteers.

Exposure to phenols reduces melanogenesis in B16F10 cells and zebrafish

Phenols, ubiquitous environmental contaminants found in water, soil, and air, pose risks to organisms even at minimal concentrations, and many are classified as hazardous pollutants. Skin pigmentation is a natural shield against ultraviolet-induced DNA damage and oxidative stress, pivotal in reducing skin cancer incidences. Studies on B16F10 melanoma cells and zebrafish offer valuable insights into potential therapeutic avenues for melanoma in the context of phenol exposure. Upon phenol treatment, there was a marked decrease in melanin content and melanogenesis-associated protein expression, such as tyrosinase and the microphthalmia-associated transcription factor (MITF) in these melanoma cells. Additionally, phenols led to diminished p38 phosphorylation, amplified extracellular signal-regulated kinase (ERK) phosphorylation, and curtailed melanin expression in zebrafish. These observations underscore the detrimental impact of phenols on melanogenesis and propose a mechanism of action centered on the ERK/p38 signaling pathway. Consequently, our data spotlight the adverse effects of phenols on melanogenesis."

Ochratoxin A-The Current Knowledge Concerning Hepatotoxicity, Mode of Action and Possible Prevention

Ochratoxin A (OTA) is considered as the most toxic of the other ochratoxins synthesized by various fungal species belonging to the Aspergillus and Penicillium families. OTA commonly contaminates food and beverages, resulting in animal and human health issues. The toxicity of OTA is known to cause liver damage and is still being researched. However, current findings do not provide clear insights into the toxin mechanism of action. The current studies focusing on the use of potentially protective compounds against the effects of the toxin are insufficient as they are mainly conducted on animals. Further research is required to fill the existing gaps in both fields (namely the exact OTA molecular mechanism and the prevention of its toxicity in the human liver). This review article is a summary of the so far obtained results of studies focusing on the OTA hepatotoxicity, its mode of action, and the known approaches of liver cells protection, which may be the base for expanding other research in near future.

Baccharis dracunculifolia DC (Asteraceae) Root Extract and Its Triterpene Baccharis Oxide Display Topical Anti-Inflammatory Effects on Different Mice Ear Edema Models

B. dracunculifolia is popularly used to treat skin diseases. This work aimed to evaluate the topical anti-inflammatory properties of B. dracunculifolia root extract (BdR) and its major compound baccharis oxide (BOx) on mice ear edema models. BdR was analyzed by GC-MS, and BOx was isolated by chromatographic fractionation. Topical anti-inflammatory activities were determined by using the croton oil, capsaicin, histamine, and phenol-induced mouse ear edema models. N-acetyl-β-D- glucosaminidase (NAG) and myeloperoxidase (MPO) activities, as well as NO dosage and histopathological analyses, were also evaluated. Phytochemical analysis of BdR showed BOx as one of the major constituents. BdR and BOx (both at 0.1, 0.5, and 1.0 mg/ear) significantly reduced croton oil, histamine, and phenol-induced ear edema, while only BOx was effective in reducing capsaicin-induced edema. MPO and NAG activities, as well as NO production, were significantly inhibited by BdR and BOx. Histopathological analysis confirmed the topical anti-inflammatory properties of BdR and BOx. Our findings showed that BdR and BOx demonstrated significant topical anti-inflammatory effects in mouse ear edema induced by different agents, suggesting their possible application on skin inflammatory diseases.

Biostimulation of tomato growth and biocontrol of Fusarium wilt disease using certain endophytic fungi

BACKGROUND

Tomato plant (Solanum lycopersicum L.) suffers from numerous fungal pathogens that cause damage to yeild production qualitatively and quantitatively. One of the most destructive disease of tomato is Fusarium wilt that caused by soil borne fungus called F. oxysporum.

METHODS

In this study, the anti-Fusarium capabilities of the foliar application of fungal endophytes extracts have been investigated on tomato under Fusarium challenges. Antifungal assay, inhibition of conidial germination, disease severity, photosynthetic pigments, osmolytes, secondary metabolites, oxidative stress, peroxidase (POD) and polyphenol oxidases (PPO) isozymes were tested for potential resistance of tomato growing under Fusarium infection.

RESULTS

Ethyl acetate extracts of A. flavus MZ045563, A. fumigatus MZ045562 and A. nidulans MZ045561 exhibited antifungal activity toward F. oxysporum where inhibition zone diameters were 15, 12 and 20 mm, respectively. Moreover, extracts of all fungal isolates at concentration 7.5 mg/mL reduced conidia germination from 94.4 to 100%. Fusarium infection caused a destructive effects on tomato plant, high severity desiese index 84.37%, reduction in growth parameters, photosynthetic pigments, and soluble protein. However, contents of proline, total phenol, malondialdehyde (MDA), hydrogen peroxide (H₂O₂) and antioxidant enzymes activity were increased in tomato plants grown under Fusarium wilt. Treatment of healthy or infected tomato plants by ethyl acetate fungal extracts showed improvements in morphological traits, photosynthetic pigments, osmolytes, total phenol and antioxidant enzymes activity. Besides, the harmful impacts of Fusarium wilt disease on tomato plants have also been reduced by lowering MDA and H₂O₂ levels. Also, treated tomato plants showed different responses in number and density of POD and PPO isozymes.

CONCLUSION

It could be suggested that application of ethyl acetate extracts of tested fungal endophytes especially combination of A. flavus, A. nidulans and A. fumigatus could be commercially used as safe biostimulation of tomato plants as well as biofungicide against tomato Fusarium wilt disease.

Traditional Uses of Animals in the Himalayan Region of Azad Jammu and Kashmir

Background: The use of animals and animal-derived products in ethnopharmacological applications is an ancient human practice that continues in many regions today. The local people of the Himalayan region harbor rich traditional knowledge used to treat a variety of human ailments. The present study was intended with the aim of examining animal-based traditional medicine utilized by the population of the Himalayan region of Azad Jammu and Kashmir.

Methods: Data were collected from 2017 to 2019 through individual and group interviews. Data on traditional uses of animal products were analyzed, utilizing following indices such as the frequency of citation, use value, relative importance, similarity index, principal component analysis, and cluster analysis to find the highly preferred species in the area.

Results: Ethnomedicinal uses of 62 species of vertebrates and invertebrates were documented. Flesh, fat, bone, whole body, milk, skin, egg, head, feathers, bile, blood, and honey were all used in these applications. The uses of 25 animals are reported here for the first time from the study area (mainly insects and birds, including iconic species like the kalij pheasant, Lophura leucomelanos; Himalayan monal, L. impejanus; and western tragopon, Tragopan melanocephalus). The diversity and range of animal-based medicines utilized in these communities are indications of their strong connections with local ecosystems.

Conclusion: Our results provide baseline data valuable for the conservation of vertebrate and invertebrate diversity in the region of Himalayan of Azad Jammu and Kashmir. It is possible that screening this fauna for medicinally active chemicals could contribute to the development of new animal-based drugs.

Transcriptional responses of Daphnia magna exposed to Akaki river water

Pollution of the aquatic environment is a global problem, with industrial waste, farming effluents, sewage, and wastewater as the main contributors. Many pollutants are biologically active at low concentrations, resulting in sublethal effects, which makes it a highly complex situation and difficult to assess. In many places, such as the Akaki river in Ethiopia, the pollution situation has resulted in streams with minimal presence of invertebrates or vertebrates. As it is difficult to perform a complete chemical analysis of the waters, the present study focused on using gene expression analysis as a biological end point to determine the effects of Akaki river contaminants. The present study was conducted using the small planktonic crustacean Daphnia magna with toxicogenomic molecular markers. Daphnia magna neonates were exposed to Akaki water samples collected from two different sites on the river and analyzed for mortality and expression of genes involved in different biological pathways. Despite the poor quality of Akaki river water, 48 h acute toxicity tests showed no mortality. Interestingly, analysis of sublethal toxicogenomic responses showed that exposure to Akaki water altered the expression of 25 out of 37 genes involved in metal regulation, immune response, oxidative stress, respiration, reproduction, and development. The toxicogenomic data gives insight into the mechanisms involved in causing potential adverse effects to aquatic biota harboring the Akaki river system.

Benchmark dose and the adverse effects of exposure to pendimethalin at low dose in female rats

Pendimethalin (PND) is a dinitroaniline herbicide widely used to control broadleaf and annual grasses. Although the acute oral toxicity of PND is >5 g/kg b.wt. in humans (LD₅₀ for rats >5000 g/kg b.wt.), it has been classified as a possible human carcinogen. It is still used in agriculture so, agricultural workers and their families, as well as consumers, can be exposed to this herbicide. The present study is the first report investigating the dose-response effect using the benchmark dose (BMD) and the adverse effects of exposure to PND at low dose via apoptosis responses linked to the expression of tumor necrosis factor-α (TNF-α), FAS, and BAX proteins; oxidative stress; and DNA and liver damage in female rats. The rats were exposed to PND via drinking water at doses equivalent to no-observed-adverse-effect level (NOAEL = 100 mg/kg b.wt.), 200, and 400 mg/kg b.wt. for 28 days. PND caused the overexpression of Tnf-α, Fas, and Bax; increased the levels of serum liver biomarkers; and increased oxidative stress in the liver and erythrocytes. Furthermore, it induced DNA and liver damage in a dose-dependent manner. The BMD showed that serum alkaline phosphatase (ALP) and total antioxidant capacity (78.4 and 30.1 mg/kg b.wt./day, respectively), lipid peroxidation in liver tissue (30.9 mg/kg b.wt./day), catalase in erythrocytes (14.0 mg/kg b.wt./day), and FAS expression in liver tissue (6.89 mg/kg b.wt./day) were highly sensitive biomarkers of PND toxicity. Our findings suggest the generation of reactive oxygen species as a possible mechanism of PND-induced gene overexpression of tumor necrosis factor-α (TNF-α), FAS, and BAX proteins, oxidative stress, and DNA and liver damage in female rats.

Phenoxyethanol-Based Embalming for Anatomy Teaching: An 18 Years' Experience with Crosado Embalming at the University of Otago in New Zealand

Embalming fixatives such as formaldehyde and phenol have been associated with occupational health hazards. While anatomists aim at replacing these chemicals, this seems presently unfeasible in particular for formaldehyde. Furthermore, fixation protocols usually require well-equipped facilities with highly experienced staff to achieve good fixation results in spite of only a minimal use of formaldehyde. Combining these aspects, a technique robust enough to be carried out by morticians is presented, resulting in durable tissues with minimal formaldehyde use. An embalming protocol involving phenoxyethanol was established, using concentrations of 7 and 1.5 Vol% of phenoxyethanol in the fixative and the conservation fluid, respectively. Visual, haptic, histological, and biomechanical properties and their perceived potential to positively influence student learning outcomes were compared to standard embalming techniques. The phenoxyethanol technique provides esthetic, durable, and odorless tissues. Bleaching is less pronounced compared to ethanol- or formaldehyde-based protocols. The tissues remain pliable following the phenoxyethanol-based embalming and can be used for biomechanical experiments to some extent. Phenoxyethanol-fixed tissues are well suited for undergraduate teaching with perceived positive learning outcomes and partly for postgraduate training. Phenoxyethanol tissues provide the option to obtain well-preserved histology samples, similar to those derived from formaldehyde. The provided protocol helps replace the use of phenol and formaldehyde for conservation purposes and minimizes the use of formaldehyde for the initial injection fixation. Phenoxyethanol-based embalming forms an effective alternative to standard embalming techniques for human cadavers. It is simple to use, allowing fixation procedures to be carried out in less sophisticated facilities with non-anatomy staff.

Solidagenone from Solidago chilensis Meyen inhibits skin inflammation in experimental models

Solidagenone (SOL) is a labdane-type diterpenoid found in Solidago chilensis, a plant traditionally used to treat skin diseases, kidney pain and ovarian inflammation. In this study, the topical anti-inflammatory activity of SOL was evaluated using in vivo and in silico assays. Croton oil-, arachidonic acid (AA)- and phenol-induced ear oedema mouse models were applied in the in vivo studies. Myeloperoxidase (MPO) and N-acetyl-β-D-glucosaminidase (NAG) activities and tumour necrosis factor alpha (TNF-α), interleukin-6 (IL-6) and nitric oxide (NO) levels were determined, as well as histopathological analyses were conducted. Interaction profiles between SOL and cyclooxygenase-1 (COX-1), cyclooxygenase-2 (COX-2), glucocorticoid receptor, estradiol-17-β-dehydrogenase and prostaglandin-E(2)-9-reductase were established using molecular docking. SOL significantly inhibited croton oil-, AA- and phenol-induced ear oedema (P < .001) at doses of 0.1, 0.5 and 1.0 mg/ear. The MPO and NAG activities and TNF-α, IL-6 and NO levels were decreased (P < .001). The histopathological data revealed that inflammatory parameters (oedema thickness, leucocyte infiltration and vasodilatation) were reduced by treatment with SOL at doses of 0.1, 0.5 and 1.0 mg/ear. The docking study showed that SOL interacts with COX-1 and prostaglandin-E(2)-9-reductase through hydrogen bonding, inhibiting these enzymes. These results indicate that SOL may be a promising compound for the treatment of cutaneous inflammatory disorders and has potential as a topical anti-inflammatory agent.

Expanding the anti-inflammatory potential of Moringa oleifera: topical effect of seed oil on skin inflammation and hyperproliferation

ETHNOPHARMACOLOGICAL RELEVANCE

Popularly used in India and sub-Hymalaian region, Moringa oleifera (Moringaceae) is associated with healing properties demonstrated in its use as treatment of acute and chronic skin diseases. Our study aimed at investigating the effects of M. oleifera seed oil (MOSO) in animal models for inflammatory and hyperproliferative skin conditions.

MATERIALS AND METHODS

MOSO was analyzed using gas chromatography/mass spectrometry. The anti-inflammatory and anti-hyperproliferative effects of treatment with either MOSO or oleic acid (OA), its main constituent, was evaluated. Acute and chronic inflammation was induced by applying 12-O-Tetradecanoylphorbol-13-acetate (TPA) and acute inflammation with either Arachidonic Acid (AA) or Phenol onto the ear of Swiss mice. Systemic activity and the influence of glucocorticoid receptors (GC) was also evaluated.

RESULTS

Topical application of MOSO and OA inhibited ear edema caused by TPA, and Phenol. Only MOSO inhibited ear edema induced by AA. Neutrophil migration was also inhibited by treatment with MOSO. Topical application of MOSO, but not OA, significantly reduced chronic skin inflammation and epidermal hypertrophy induced by multiple TPA applications. Pre-treatment with GC antagonist mifepristone reversed the anti-inflammatory effect of MOSO and OA on the TPA model. Repeated administration of MOSO show a similar effect to dexamethasone on thymus weight, though MOSO did not present any influence on skin thickness, as well as in the weight of the spleen, adrenal gland and lymph node.

CONCLUSION

The results suggest that MOSO is effective as a treatment for skin diseases that rely on keratinocyte hyperproliferation. OA is also effective in acute inflammation. Both MOSO and OA depend on GC activation for anti-inflammatory effect but do not exhibit the same adverse effects seen in topical treatment with dexamethasone. We hereby evidence the use of MOSO as a topical anti-inflammatory agent in inflammatory skin diseases, thus, expanding its therapeutic potential.

Fish oil preparation inhibits leukocyte recruitment and bands that characterize inflamed tissue in a model of phenol-induced skin inflammation: percutaneous penetration of a topically applied preparation demonstrated by photoacoustic spectroscopy

Fish oil (FO) is a natural source of omega-3 fatty acids, with well-established beneficial effects in inflammatory diseases when FO is orally administered. This study investigated the effects of a topically applied FO preparation (FOP) on phenol-induced ear edema and evaluated the percutaneous penetration of FOP in ear tissue. After applying phenol, groups of mice received FOP on the ear. After 1 h, ear tissue was collected to determine the percent inhibition of edema, myeloperoxidase activity, and to perform photoacoustic spectroscopy (PAS). Treatment with FOP did not reduce edema, but reduced myeloperoxidase activity. The FOP decreased the area of bands that characterize inflamed tissue and penetrated into the tissue. These results indicated an inhibitory effect of FOP on leukocyte recruitment in phenol-induced ear edema. These data support the applicability of PAS as a non-destructive method for evaluating the inflammatory response, percutaneous penetration and antiinflammatory activity of compounds.

Topical Anti-Inflammatory and Analgesic Activities of Citrullus colocynthis Extract Cream in Rats

Background and objectives:Citrullus colocynthis (CC), known as bitter apple, is used to treat diabetes in Iranian traditional medicine. The aim of this study is to evaluate the anti-inflammatory and analgesic activities of CC cream in rats. Materials and Methods: The carrageenan-induced edema in a rat hind paw was carried out to evaluate the topical anti-inflammatory effect of the CC fruit extract cream (2–8%) and the tissue levels of IL-6 and TNF-α were estimated by using a commercial ELISA kit. The topical antinociceptive activity of CC cream (2–8%) was evaluated in the rat formalin test. To determine the role of opioid receptors in the local antinociceptive effect of the CC cream, naloxone (20 μg/paw, i.pl.), a non-selective opioid antagonist, was used. Results: The results showed that the CC cream (2–8%) dose-dependently reduced the carrageenan-induced paw edema and reversed the changes in the level of TNF-α and IL-6 due to carrageenan-induced edema (p < 0.01). The anti-inflammatory effect of CC cream 8% was comparable to that of hydrocortisone ointment 1%. Furthermore, the application of CC cream (2–8%) dose-dependently inhibited both first and second phases of the formalin test (p < 0.05). The antinociceptive effect of the CC cream (8%) was comparable to that of methyl salicylate cream 30%. Moreover, the administration of naloxone significantly reversed the topical antinociceptive effect of the CC cream (p < 0.05). Conclusions: For the first time, this study indicated that the topical application of CC cream possesses significant anti-inflammatory and antinociceptive activities in animal models, which were probably mediated by opioid receptors and the suppression of pro-inflammatory cytokines (TNF-α and IL-6). Thus, the CC cream can be used to treat inflammatory pain and inflammatory diseases.

Anti-Inflammatory Activity of Babassu Oil and Development of a Microemulsion System for Topical Delivery

Babassu oil extraction is the main income source in nut breakers communities in northeast of Brazil. Among these communities, babassu oil is used for cooking but also medically to treat skin wounds and inflammation, and vulvovaginitis. This study aimed to evaluate the anti-inflammatory activity of babassu oil and develop a microemulsion system with babassu oil for topical delivery. Topical anti-inflammatory activity was evaluated in mice ear edema using PMA, arachidonic acid, ethyl phenylpropiolate, phenol, and capsaicin as phlogistic agents. A microemulsion system was successfully developed using a Span® 80/Kolliphor® EL ratio of 6 : 4 as the surfactant system (S), propylene glycol and water (3 : 1) as the aqueous phase (A), and babassu oil as the oil phase (O), and analyzed through conductivity, SAXS, DSC, TEM, and rheological assays. Babassu oil and lauric acid showed anti-inflammatory activity in mice ear edema, through inhibition of eicosanoid pathway and bioactive amines. The developed formulation (39% A, 12.2% O, and 48.8% S) was classified as a bicontinuous to o/w transition microemulsion that showed a Newtonian profile. The topical anti-inflammatory activity of microemulsified babassu oil was markedly increased. A new delivery system of babassu microemulsion droplet clusters was designed to enhance the therapeutic efficacy of vegetable oil.

Evidence of Bioactive Compounds from Vernonia polyanthes Leaves with Topical Anti-Inflammatory Potential

Vernonia polyanthes Less. (Asteraceae), popularly known as "assa-peixe", is a plant species used in Brazilian traditional medicine for the treatment of cutaneous damage, cicatrization, inflammation, and rheumatism. Based on these ethnopharmacological findings, the current study evaluated the topical anti-inflammatory effects of the hexane (HEVP) and ethyl acetate (EAEVP) extracts from V. polyanthes leaves in experimental models of skin inflammation. Chemical characterization was carried out by HPLC-UV/DAD analysis. Anti-inflammatory activity was evaluated using Croton oil-, arachidonic acid (AA)-, phenol-, ethyl phenylpropiolate (EPP)-, and capsaicin-induced ear edema models in mice. Histopathological evaluation and measurements of myeloperoxidase (MPO) and N-acetyl-β-d-glucosaminidase (NAG) enzymes were also performed. Rutin, luteolin, and apigenin were identified in EAEVP. Topically applied HEVP and EAEVP significantly (p < 0.05, p < 0.01 or p < 0.001) reduced edema induced by five different irritants at the doses tested (0.1, 0.5 and 1.0 mg/ear). Histopathological analysis revealed a reduction of edema, inflammatory cell infiltration, and vasodilation. In addition, the enzymes activity (MPO and NAG) in the ear tissues was reduced by the topical treatment of HEVP and EAEVP (p < 0.05, p < 0.01 or p < 0.001). The results suggest that V. polyanthes leaves are effective against cutaneous damage, which support its traditional use and open up new possibilities for the treatment of skin disorders.

Ochratoxin A: Molecular Interactions, Mechanisms of Toxicity and Prevention at the Molecular Level

Ochratoxin A (OTA) is a widely-spread mycotoxin all over the world causing major health risks. The focus of the present review is on the molecular and cellular interactions of OTA. In order to get better insight into the mechanism of its toxicity and on the several attempts made for prevention or attenuation of its toxic action, a detailed description is given on chemistry and toxicokinetics of this mycotoxin. The mode of action of OTA is not clearly understood yet, and seems to be very complex. Inhibition of protein synthesis and energy production, induction of oxidative stress, DNA adduct formation, as well as apoptosis/necrosis and cell cycle arrest are possibly involved in its toxic action. Since OTA binds very strongly to human and animal albumin, a major emphasis is done regarding OTA-albumin interaction. Displacement of OTA from albumin by drugs and by natural flavonoids are discussed in detail, hypothesizing their potentially beneficial effect in order to prevent or attenuate the OTA-induced toxic consequences.

Obesity and colorectal cancer: molecular features of adipose tissue

The huge part of population in developed countries is overweight or obese. Obesity is often determined by body mass index (BMI) but new accurate methods and ratios have recently appeared to measure body fat or fat located in the intestines. Early diagnosis of obesity is crucial since it is considered an increasing colorectal cancer risk factor. On the one hand, colorectal cancer has been strongly associated with lifestyle factors. A diet rich in red and processed meats may increase colorectal cancer risk; however, high-fiber diets (grains, cereals and fruits) have been associated with a decreased risk of colorectal cancer. Other life-style factors associated with obesity that also increase colorectal cancer risk are physical inactivity, smoking and high alcohol intake. Cutting-edge studies reported that high-risk transformation ability of adipose tissue is due to production of different pro-inflammatory cytokines like IL-8, IL-6 or IL-2 and other enzymes like lactate dehydrogenase (LDH) and tumour necrosis factor alpha (TNFα). Furthermore, oxidative stress produces fatty-acid peroxidation whose metabolites possess very high toxicities and mutagenic properties. 4-hydroxy-2-nonenal (4-HNE) is an active compounds that upregulates prostaglandin E2 which is directly associated with high proliferative colorectal cancer. Moreover, 4-HNE deregulates cell proliferation, cell survival, differentiation, autophagy, senescence, apoptosis and necrosis via mitogen-activated protein kinase (MAPK), phosphoinositide 3-kinase (PIK3CA)—AKT and protein kinase C pathways. Other product of lipid peroxidation is malondialdehyde (MDA) being able to regulate insulin through WNT-pathway as well as having demonstrated its mutagenic capability. Accumulation of point mutation enables genomic evolution of colorectal cancer described in the model of Fearon and Vogelstein. In this review, we will summarize different determination methods and techniques to assess a truthfully diagnosis and we will explain some of the capabilities that performs adipocytes as the largest endocrine organ.

Pereskia aculeata Miller leaves present in vivo topical anti-inflammatory activity in models of acute and chronic dermatitis

ETHNOPHARMACOLOGICAL RELEVANCE

The leaves of Pereskia aculeata Miller (Cactaceae), known as Barbados gooseberry, are used in Brazilian traditional medicine as emollients and to treat skin wounds and inflammation. This study investigated the topical anti-inflammatory activity of the hexane fraction (HF) obtained from the methanol extract of the leaves of this species in models of acute and chronic ear dermatitis in mice.

MATERIAL AND METHODS

Mice ear edema was induced by topical application of croton oil, arachidonic acid, capsaicin, ethyl-phenylpropiolate and phenol; and by subcutaneous injection of histamine. Ear biopsies were obtained to determine the levels of IL-1β, IL-6 and TNF-α cytokines by ELISA assay. Histopathological analysis was also performed to evaluate the HF activity in croton oil multiple application test. In addition, acute dermal irritation/corrosion test in rats was accomplished. HF chemical characterization was performed by GC-MS analysis.

RESULTS

HF intensively reduced the inflammatory process induced by all irritant agents used, except for arachidonic acid. This activity is related, at least in part, to the reduction of IL-6 and TNF-α cytokines levels. Moreover, when the glucocorticoid receptor antagonist mifepristone was used, HF failed to respond to the croton oil application.The results strongly suggested a glucocorticoid-like effect, which was reinforced by the presence of considerable amounts of sterol compounds identified in HF. The acute dermal irritaton/corrosion test showed no signs of toxicity.

CONCLUSIONS

This study showed that the acute and chronic anti-inflammatory activity of P. aculeata leaves is very promising, and corroborates to better understand their ethnopharmacological applications.

Topical application of the hexane fraction of Lacistema pubescens reduces skin inflammation and cytokine production in animal model

OBJECTIVES

The aim of this study was to investigate the acute topical anti-inflammatory effect of the hexane fraction (HLP) of Lacistema pubescens in mice.

METHODS

Ear oedema models induced by croton oil, arachidonic acid, phenol, histamine, ethyl phenyl propiolate and capsaicin. Histopathological analyses of ear tissue samples sensitized with croton oil were performed. Myeloperoxidase activity (MPO), the pro-inflammatory cytokine-inhibitory effect and dermatoxicity were also evaluated.

KEY FINDINGS

HLP (1, 0.5 and 0.1 mg/ear) resulted in a substantial reduction in skin thickness or tissue weight on all models tested, except for capsaicin-induced ear oedema, similar to dexamethasone (0.1 mg/ear) and/or indomethacin (0.5 mg/ear). Histopathological analyses and neutrophil-mediated MPO activity confirmed the topical anti-inflammatory effect of HLP. In addition, HLP reduced IL-1β, IL-6 and tumour necrosis factor-α cytokine levels. Sitosterol-rich fraction (SRF), obtained from HLP fractionation, reduced ear oedema on croton oil and phenol models at the same dose of dexamethasone (0.1 mg/ear). No dermotoxicity was observed.

CONCLUSIONS

The mechanism of action of HLP was associated with the inhibition of several pro-inflammatory mediators, including cytokines, arachidonic acid metabolites and histamine, which suggested a glucocorticoid-like effect, reinforced by the presence of the steroid sitosterol. This is the first report on anti-inflammatory activity of L. pubescens leaves.

Comparison of modified Thiel embalming and ethanol-glycerin fixation in an anatomy environment: Potentials and limitations of two complementary techniques

Thiel-fixed specimens have outstandingly lifelike visual and haptic properties. However, the original Thiel method is expensive and requires an elaborate setup. It is therefore of principal interest to modify the Thiel method in order to make it available to a broader user group. A modified Thiel embalming method will be described in detail and compared to ethanol-glycerin fixation with the help of illustrative examples. The visual properties, haptic properties, the usability for performing histological investigations, costs and potential health aspects will be considered. Tissues fixed with the modified Thiel technique gave results similar to the original method, providing more realistic visual and haptic properties than ethanol-glycerin embalming. However, Thiel fixation is significantly more expensive and requires more precautions to minimize potential health hazards than ethanol-glycerin-fixed tissues. In contrast to ethanol-glycerin-fixed specimens, the Thiel-fixed specimens are not suitable for histological investigations. Both modes of fixation are inappropriate for biomechanical testing. Modified Thiel embalming simplifies the availability of body donors with lifelike properties and has cost-saving advantages to the original technique. Thiel-embalmed body donors are ideally suited for clinical workshops but have restrictions for student dissection courses in facilities with limited storage space, air circulation or technical staff. Vice versa, ethanol-glycerin-fixed body donors are well suited for student dissection courses in such an environment but are limited in their use for clinical workshops. Modified Thiel embalming therefore ideally complements ethanol-glycerin fixation in order to provide customized solutions for clinical workshops and student dissection courses in a wide range of applications.

Phenolic excipients of insulin formulations induce cell death, pro-inflammatory signaling and MCP-1 release

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Insulin formulations are cytotoxic in vitro.

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Toxicity is caused by the excipients phenol and m-cresol.

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Phenolic excipients activate stress kinases and attenuate AKT phosphorylation.

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Phenolic excipients induce pro-inflammatory responses and MCP-1 release.

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The toxic effects of excipients might explain inflammation of infusion sites in vivo.

Skin reactions at the infusion site are a common side effect of continuous subcutaneous insulin infusion therapy. We hypothesized that local skin complications are caused by components of commercial insulin formulations that contain phenol or m-cresol as excipients. The toxic potential of insulin solutions and the mechanisms leading to skin reactions were explored in cultured cells.

The toxicity of insulin formulations (Apidra, Humalog, NovoRapid, Insuman), excipient-free insulin, phenol and m-cresol was investigated in L929 cells, human adipocytes and monocytic THP-1 cells. The cells were incubated with the test compounds dose- and time-dependently. Cell viability, kinase signaling pathways, monocyte activation and the release of pro-inflammatory cytokines were analyzed.

Insulin formulations were cytotoxic in all cell-types and the pure excipients phenol and m-cresol were toxic to the same extent. P38 and JNK signaling pathways were activated by phenolic compounds, whereas AKT phosphorylation was attenuated. THP-1 cells incubated with sub-toxic levels of the test compounds showed increased expression of the activation markers CD54, CD11b and CD14 and secreted the chemokine MCP-1 indicating a pro-inflammatory response.

Insulin solutions displayed cytotoxic and pro-inflammatory potential caused by phenol or m-cresol. We speculate that during insulin pump therapy phenol and m-cresol might induce cell death and inflammatory reactions at the infusion site in vivo. Inflammation is perpetuated by release of MCP-1 by activated monocytic cells leading to enhanced recruitment of inflammatory cells. To minimize acute skin complications caused by phenol/m-cresol accumulation, a frequent change of infusion sets and rotation of the infusion site is recommended.

Anti-inflammatory effects of Bryophyllum pinnatum (Lam.) Oken ethanol extract in acute and chronic cutaneous inflammation

ETHNOPHARMACOLOGICAL RELEVANCE

Bryophyllum pinnatum (Lam.) Oken (Crassulaceae), popularly known in Brazil as "folha-da-fortuna", is a plant species used in folk medicine for the external and internal treatment of inflammation, infection, wound, burn, boil, ulcers and gastritis, and several other diseases. The present study aimed to perform the chemical characterization and the evaluation of the topical anti-inflammatory effect of the ethanol extract of Bryophyllum pinnatum leaves (EEBP) in acute and chronic mice ear edema models induced by different irritant agents.

MATERIALS AND METHODS

The EEBP chemical characterization was performed by HPLC-UV DAD. Ear edema on Swiss mice was induced by the topical application of Croton oil (single and multiple applications), arachidonic acid, phenol, capsaicin and ethyl phenylpropiolate (EPP). The topical anti-inflammatory effect of EEBP was evaluated by measuring the ear weight (acute inflammation models) and thickness (chronic inflammation model). Histopathological analyses of ear tissue samples sensitized with Croton oil (single and multiple applications) were also performed.

RESULTS

The flavonoids rutin, quercetin, luteolin and luteolin7-O-β-d-glucoside were detected in EEBP. Topical application of EEBP significantly (P<0.001) inhibited the ear edema induced by Croton oil single application (inhibition of 57%), arachidonic acid (inhibition of 67%), phenol (inhibition of 80%), capsaicin (inhibition of 72%), EPP (inhibition of 75%) and Croton oil multiple application (55% after 9 days). Histopathological analyses confirmed the topical anti-inflammatory effect of EEBP since it was observed reduction of edema, epidermal hyperplasia, inflammatory cells infiltration and vasodilation.

CONCLUSIONS

The results suggest that EEBP is effective as a topical anti-inflammatory agent in acute and chronic inflammatory processes possibly due to inhibition of arachidonic acid pathway, which justify the traditional use of Bryophyllum pinnatum as a remedy for skin disorders.

Cecropia pachystachya: a species with expressive in vivo topical anti-inflammatory and in vitro antioxidant effects

Cecropia pachystachya is a species traditionally used in Brazil to treat inflammation. This work aims to evaluate the topical anti-inflammatory and antioxidant activities of the methanolic extract of C. pachystachya (CPM) and to perform its chemical fingerprint by HPLC-DAD. The topical anti-inflammatory activity was evaluated using the mouse models of acute ear inflammation induced by croton oil, arachidonic acid, capsaicin, EPP, phenol, and chronic inflammation induced by multiple application of croton oil. The in vitro antioxidant effect of CPM was investigated using DPPH, reducing power, β-carotene bleaching, and TBARS assays. HPLC analysis was performed to quantify the antioxidant phenolics orientin, isoorientin, and chlorogenic acid previously identified in CPM. CPM exhibited significant anti-inflammatory effect in the acute models, in some cases comparable to the reference drugs. Histopathological analysis showed a moderate chronic skin anti-inflammatory effect with decrease in vasodilation, edema, cell infiltration, and epidermal hyperproliferation. It also showed strong in vitro antioxidant activity. The contents of orientin, isoorientin, and chlorogenic acid were 66.5 ± 1.8, 118.8 ± 0.7, and 5.4 ± 0.2 µg/mg extract, respectively. The topical anti-inflammatory activity of CPM could be based on its antioxidant properties, although other effects are probably involved, including COX inhibition and other mechanisms.

Topical anti-inflammatory potential of standardized pomegranate rind extract and ellagic acid in contact dermatitis

The present study evaluated the topical anti-inflammatory potential of a standardized pomegranate rind extracts (SPRE) in parallel with its marker compound ellagic acid (EA, 13% w/w) against a mouse model of contact dermatitis. In the phenol-induced mouse ear edema, topical application of SPRE (5, 2.5, and 1 mg/ear) and EA (0.65, 0.325, and 0.13 mg/ear, equivalent to its content in SPRE) dose-dependently reduced the ear edema with the maximal inhibition of 79.12% and 73.63%, respectively. Triamcinolone (0.1 mg/ear) and diclofenac (1 mg/ear) as reference drugs inhibited the edema by 73.63% and 37.91%. Myeloperoxidase (MPO) activity in the mouse ear was also decreased by SPRE and EA up to 69.68% and 68.79%, respectively. Triamcinolone and diclofenac decreased the MPO activity by 76.66% and 80.14% similarly. The results indicated that topical application of SPRE and EA is promising for use in the treatment of inflammatory skin disorders.

Ethanol-glycerin fixation with thymol conservation: a potential alternative to formaldehyde and phenol embalming

Anatomical fixation and conservation are required to prevent specimens from undergoing autolysis and decomposition. While fixation is the primary arrest of the structures responsible for autolysis and decomposition, conservation preserves the state of fixation. Although commonly used, formaldehyde has been classified as carcinogenic to humans. For this reason, an adequate substitute was developed. Ethanol-glycerin fixation and thymol conservation are described and compared with formaldehyde and phenol in this technical report. The setup, tissue qualities, financial aspects, and health concerns of this method are discussed. Ethanol-glycerin fixation and thymol conservation provide outstanding haptic and optic tissue qualities. Typical formaldehyde and phenol effects, such as skin, airway, and eye irritation, as well as carcinogenic effects, can be circumvented by using ethanol-glycerin and thymol instead. Ethanol-glycerin fixation is more expensive than formaldehyde and requires an explosion-proof facility. However, the absence of health effects and its convincing tissue qualities balance these higher costs. Therefore, ethanol-glycerin fixation and thymol conservation provide a potential alternative and complement established fixation techniques. The use of carcinogenic formaldehyde and toxic phenol can be effectively restricted through the use of the described method.

Glutathione homeostasis and functions: potential targets for medical interventions

Glutathione (GSH) is a tripeptide, which has many biological roles including protection against reactive oxygen and nitrogen species. The primary goal of this paper is to characterize the principal mechanisms of the protective role of GSH against reactive species and electrophiles. The ancillary goals are to provide up-to-date knowledge of GSH biosynthesis, hydrolysis, and utilization; intracellular compartmentalization and interorgan transfer; elimination of endogenously produced toxicants; involvement in metal homeostasis; glutathione-related enzymes and their regulation; glutathionylation of sulfhydryls. Individual sections are devoted to the relationships between GSH homeostasis and pathologies as well as to developed research tools and pharmacological approaches to manipulating GSH levels. Special attention is paid to compounds mainly of a natural origin (phytochemicals) which affect GSH-related processes. The paper provides starting points for development of novel tools and provides a hypothesis for investigation of the physiology and biochemistry of glutathione with a focus on human and animal health.

Structure-activity relationships imply different mechanisms of action for ochratoxin A-mediated cytotoxicity and genotoxicity

Ochratoxin A (OTA) is a fungal toxin that is classified as a possible human carcinogen based on sufficient evidence for carcinogenicity in animal studies. The toxin is known to promote oxidative DNA damage through production of reactive oxygen species (ROS). The toxin also generates covalent DNA adducts, and it has been difficult to separate the biological effects caused by DNA adduction from that of ROS generation. In the current study, we have derived structure-activity relationships (SAR) for the role of the C5 substituent of OTA (C5-X = Cl) by first comparing the ability of OTA, OTBr (C5-X = Br), OTB (C5-X = H), and OTHQ (C5-X = OH) to photochemically react with GSH and 2'-deoxyguanosine (dG). OTA, OTBr, and OTHQ react covalently with GSH and dG following photoirradiation, while the nonchlorinated OTB does not react photochemically with GSH and dG. These findings correlate with their ability to generate covalent DNA adducts (direct genotoxicity) in human bronchial epithelial cells (WI26) and human kidney (HK2) cells, as evidenced by the (32)P-postlabeling technique. OTB lacks direct genotoxicity, while OTA, OTBr, and OTHQ act as direct genotoxins. In contrast, their cytotoxicity in opossum kidney epithelial cells (OK) and WI26 cells did not show a correlation with photoreactivity. In OK and WI26 cells, OTA, OTBr, and OTB are cytotoxic, while the hydroquinone OTHQ failed to exhibit cytotoxicity. Overall, our data show that the C5-Cl atom of OTA is critical for direct genotoxicity but plays a lesser role in OTA-mediated cytotoxicity. These SARs suggest different mechanisms of action (MOA) for OTA genotoxicity and cytotoxicity and are consistent with recent findings showing OTA mutagenicity to stem from direct genotoxicity, while cytotoxicity is derived from oxidative DNA damage.

An update on direct genotoxicity as a molecular mechanism of ochratoxin a carcinogenicity

Ochratoxin A (OTA) is a naturally occurring chlorophenolic fungal toxin that contaminates a wide range of food products and poses a cancer threat to humans. The mechanism of action (MOA) for OTA renal carcinogenicity is a controversial issue. In 2005, direct genotoxicity (covalent DNA adduct formation) was proposed as a MOA for OTA-mediated carcinogenicity [ Manderville , R. A. ( 2005 ) Chem. Res. Toxicol. 18 , 1091 - 1097 ]. At that time, inconsistent results had been published on OTA genotoxicity/mutagenicity, and conclusive evidence for OTA-mediated DNA adduction had been lacking. In this update, published data from the past 6-7 years are presented that provide new hypotheses for the MOA of OTA-mediated carcinogenicity. While direct genotoxicity remains a controversial issue for OTA, new findings from the Umemura and Nohmi laboratories provide definitive results for the mutagenicity of OTA in the target tissue (outer medulla) of male rat kidney that rules out oxidative DNA damage. These findings, coupled with our own efforts that provide new structural evidence for DNA adduction by OTA, has strengthened the argument for involvement of direct genotoxicity in OTA-mediated renal carcinogenesis. This MOA should be taken into consideration for OTA human risk assessment.

Fluorescent properties and conformational preferences of C-linked phenolic-DNA adducts

Phenolic toxins and mutagenic diazoquinones generate C-linked adducts at the C8 site of 2'-deoxyguanosine (dG) through the intermediacy of radical species. We have previously reported the site-specific incorporation of these adducts into oligonucleotides using a postsynthetic palladium-catalyzed cross-coupling strategy [Omumi (2011 ) J. Am. Chem. Soc. 133 , 42 - 50 ]. We report here the structural impact of these lesions within two decanucleotide sequences containing either 5'- and 3'-flanking pyrimidines or purines. In the complementary strands, the base opposite (N) the C-linked adduct was varied to determine the possibility of mismatch stabilization by the modified nucleobases. The resulting adducted duplex structures were characterized using UV thermal denaturation studies, circular dichroism, fluorescence spectroscopy, and molecular dynamics (MD) simulations. The experimental data showed the C-linked adducts to destabilize the duplex when base paired with its normal partner C but to increase duplex stability within a G:G mismatch. The stabilization within the G:G mismatch was sequence dependent, with flanking purine bases playing a key role in the stabilizing influence of the adduct. MD simulations showed no large structural changes to the B form double helix, regardless of the (anti/syn) adduct preference. Consideration of H-bonding and stacking interactions derived from the MD simulations together with the thermal melting data and changes in fluorescent emission of the adducts upon hybridization to the complementary strands implied that the C-linked phenolic adducts preferentially adopt the syn-conformation within both duplexes regardless of the opposite base N. Given that biological outcome in terms of mutagenicity appears to be strongly correlated to the conformational preference of the corresponding N-linked C8-dG adducts, the potential biological implications of phenolic C-linked adducts are discussed.

Topical anti-inflammatory effect of Caryocar coriaceum Wittm. (Caryocaraceae) fruit pulp fixed oil on mice ear edema induced by different irritant agents

AIM OF THE STUDY

Caryocar coriaceum Wittm. fruit pulp fixed oil (CCFO) has been widely employed by communities from Brazil Northeastern in the treatment of skin inflammation, respiratory affections, wound healing and muscle pain. In this study, we evaluated the topical effect of CCFO against different irritant agents in vivo, in order to verify its antiedematous effect as well to unravel its tentative mechanisms of action.

MATERIALS AND METHODS

CCFO was obtained from Caryocar coriaceum fruits using ethyl acetate as solvent. Ear edema provoked by the application of Croton oil (single and multiple applications), arachidonic acid (AA), capsaicin, phenol and histamine to Swiss mice was used to evaluate the topical anti-inflammatory effect of CCFO. Histological analysis from mice ears sensitized with Croton oil and AA single application was also performed.

RESULTS

Crude CCFO (20μL/ear) demonstrated significant topical antiedematous effect against Croton oil single (inhibition of 32.0%; P<0.05) and multiple (41.4% after 9 days, P<0.001) applications, AA (inhibition of 49.7%; P<0.01) and phenol (inhibition of 38.8%; P<0.001). In contrast, CCFO did not antagonize the edema caused by topical treatment with capsaicin and histamine when compared to control group (P>0.05). Histological analysis also revealed that CCFO was able to reduce the edema and the influx of inflammatory cells in mice ears sensitized with Croton oil and AA.

CONCLUSIONS

CCFO exhibited a similar profile of topical anti-inflammatory activity to that of drugs that classically modulate the production of arachidonic acid metabolites. The study also indicates the potential application of CCFO as an important herbal medicine to be used against skin inflammatory diseases.

Topical anti-inflammatory activity of body fat from the lizard Tupinambis merianae

AIM OF THE STUDY

Tupinambis merianae is one of the most frequently used animals in traditional medicine in Brazil as its body fat has many different therapeutic indications as a folk remedy. The present study evaluated the topical anti-inflammatory activity of Tupinambis merianae fat in treating ear edema in an animal model.

MATERIALS AND METHODS

Oil (OTM) was extracted from body fat located in the ventral region of Tupinambis merianae using hexane as a solvent. Ear edema provoked by the application of croton oil (single and multiple application), arachidonic acid, phenol and capsaicin to Swiss mice was used to evaluate the potential anti-inflammatory value of the topical use of OTM. Topical applications of these irritants were made to the right ears of animals that were pre-treated with a acetone (control), dexamethasone, or OTM.

RESULTS

Our results indicate that Tupinambis merianae fat demonstrates significant topical antiinflammatory activity that reduces inflammation related to ear edema caused by croton oil (single and multiple application), arachidonic acid, phenol. While the inflammation caused by capsaicin, OTM did not significantly reduce the edema.

CONCLUSION

This represents the first evidence of anti-inflammatory activity of Tupinambis merianae fat in in vivo models, confirming its usefulness in traditional medicine as a remedy for skin diseases (dermatitis). The fatty acids present in OTM most likely inhibit the response pathway of arachidonic acid and its metabolites, thus reducing the production of pro-inflammatory mediators.

Oxidative stress and sodium methyldithiocarbamate-induced modulation of the macrophage response to lipopolysaccharide in vivo

Sodium methyldithiocarbamate (SMD) is the third most abundantly used conventional pesticide in the United States, and hundreds of thousands of persons are exposed to this compound or its major breakdown product, methylisothiocyanate, at levels greater than recommended by the Environmental Protection Agency. A previous study suggests three mechanisms of action involved to some degree in the inhibition of inflammation and decreased resistance to infection caused by exposure of mice to the compound. One of these mechanisms is oxidative stress. The purpose of the present study was to confirm that this mechanism is involved in the effects of SMD on cytokine production by peritoneal macrophages and to further characterize its role in altered cytokine production. Results indicated that SMD significantly decreased the intracellular concentration of reduced glutathione (GSH), suggesting oxidative stress. This was further indicated by the upregulation of genes involved in the "response to oxidative stress" as determined by microarray analysis. These effects were associated with the inhibition of lipopolysaccharide (LPS)-induced production of several proinflammatory cytokines. Experimental depletion of GSH with buthionine sulfoximine (BSO) partially prevented the decrease in LPS-induced interleukin (IL)-6 production caused by SMD and completely prevented the decrease in IL-12. In contrast, BSO plus SMD substantially enhanced the production of IL-10. These results along with results from a previous study are consistent with the hypothesis that SMD causes oxidative stress, which contributes to modulation of cytokine production. However, oxidative stress alone cannot explain the increased IL-10 production caused by SMD.