Nanoemulsified Essential Oil of Melaleuca leucadendron Leaves for Topical Application: In Vitro Photoprotective, Antioxidant and Anti-Melanoma Activities.

Melanoma, primarily caused by solar ultraviolet (UV) radiation, can be prevented by the use of sunscreens. However, the use of synthetic sunscreens raises environmental concerns. Natural compounds with antioxidant photoprotective properties and cytotoxic effects against cancer cells can be promising for the prevention and treatment of melanoma with less environmental effect. This study focuses on Melaleuca leucadendron essential oil (EO) for photoprotection and antitumor applications. EO was hydrodistilled from M. leucadendron leaves with a 0.59% yield. Gas chromatography-mass spectrometry detected monoterpenes and sesquiterpenes. Nanoemulsions were prepared with (NE-EO) and without EO (NE-B) using the phase inversion method, showing good stability, spherical or oval morphology, and a pseudoplastic profile. Photoprotective activity assessed spectrophotometrically showed that the NE-EO was more effective than NE-B and free EO. Antioxidant activity evaluated by DPPH and ABTS methods indicated that pure and nanoemulsified EO mainly inhibited the ABTS radical, showing IC50 40.72 and 5.30 µg/mL, respectively. Cytotoxicity tests on L-929 mouse fibroblasts, NGM human melanocyte, B16-F10 melanoma, and MeWo human melanoma revealed that EO and NE-EO were more cytotoxic to melanoma cells than to non-tumor cells. The stable NE-EO demonstrates potential for melanoma prevention and treatment. Further research is required to gain a better understanding of these activities.

Protium spruceanum Extract Enhances Mupirocin Activity When Combined with Nanoemulsion-Based Hydrogel: A Multi-Target Strategy for Treating Skin and Soft Tissue Infections.

The treatment of skin and soft tissue infections (SSTIs) can be challenging due to bacterial resistance, particularly from strains like MRSA and biofilm formation. However, combining conventional antibiotics with natural products shows promise in treating SSTIs. The objective of this study is to develop a nanoemulsion-based hydrogel containing Protium spruceanum extract and mupirocin and evaluate its potential for the treatment of SSTIs. The nanoemulsion was obtained by phase inversion and subsequently characterized. The antibacterial activity was evaluated in vitro against S. aureus MRSA, including the synergism of the combination, changes in membrane permeability using flow cytometry, and the anti-biofilm effect. In addition, the irritative potential was evaluated by the HET-CAM assay. The combination exhibited synergistic antibacterial activity against S. aureus and MRSA due to the extract enhancing membrane permeability. The hydrogel demonstrated suitable physicochemical properties, inhibited biofilm formation, and exhibited low irritation. The formulation was nanometric (176.0 ± 1.656 nm) and monodisperse (polydispersity index 0.286 ± 0.011). It exhibited a controlled release profile at 48 h and high encapsulation efficacy (94.29 ± 4.54% for quercitrin and 94.20 ± 5.44% for mupirocin). Therefore, these findings suggest that the hydrogel developed could be a safe and effective option for treating SSTIs.

Silymarin inhibits the lipogenic pathway and reduces worsening of non-alcoholic fatty liver disease (NAFLD) in mice.

CONTEXT: The role of silymarin in hepatic lipid dysfunction and its possible mechanisms of action were investigated. OBJECTIVE: To evaluate the effects of silymarin on hepatic and metabolic profiles in mice fed with 30% fructose for 8 weeks. METHODS: We evaluated the antioxidant profile of silymarin; mice consumed 30% fructose and were treated with silymarin (120 mg/kg/day or 240 mg/kg/day). We performed biochemical, redox status, and histopathological assays. RT-qPCR was performed to detect ACC-1, ACC-2, FAS, and CS expression, and western blotting to detect PGC-1α levels. RESULTS: Silymarin contains high levels of phenolic compounds and flavonoids and exhibited significant antioxidant capacity in vitro. In vivo, the fructose-fed groups showed increased levels of AST, ALT, SOD/CAT, TBARS, hepatic TG, and cholesterol, as well as hypertriglyceridaemia, hypercholesterolaemia, and increased ACC-1 and FAS. Silymarin treatment reduced these parameters and increased mRNA levels and activity of hepatic citrate synthase. CONCLUSIONS: These results suggest that silymarin reduces worsening of NAFLD.

Effects of Psidium guajava L. leaves extract on blood pressure control and IL-10 production in salt-dependent hypertensive rats.

Psidium guajava (guava) leaves extract displays anti-hypertensive properties by mechanisms not yet fully understood. Here, we investigated whether sympathetic drive and immune signaling mechanisms are involved with the antihypertensive effect of the guava extract in a model of salt-dependent hypertension. Raw guava extract (rPsE) was characterized by colorimetric and UPLC-MS techniques. Two doses of rPsE (100 and 200 mg/kg) were evaluated for anti-hypertensive effect using a suspension system (PsE). Weaned male Wistar rats were put on a high-salt diet (HSD, 0.90 % Na+) for 16 weeks and received gavages of PsE for the last 4 weeks. Blood pressure (BP) was measured at the end of treatment in conscious rats. The neurogenic pressor effect was assessed by ganglionic blockade with hexamethonium. Autonomic modulation of heart rate was evaluated by spectral analysis. The effects of orally administered PsE on lumbar sympathetic nerve activity (LSNA) were assessed in anesthetized rats. Blood IL-10, IL-17A, and TNF were measured. The increased neurogenic pressor effect of HSD rats was reduced by PsE 100 mg/kg, but not by 200 mg/kg. PsE (200 mg/kg) administration in anesthetized rats produced a greater fall in BP of HSD rats compared to standard salt diet (SSD) rats. PsE hypotensive response elicited an unproportionable increase in LSNA of HSD rats compared to SSD rats. PsE (200 mg/kg) increased plasma concentrations of IL-10 but had no effect on TNF or IL-17A. Our data indicate that the antihypertensive effects of PsE may involve autonomic mechanisms and immunomodulation by overexpression of IL-10 in salt-dependent hypertensive rats.

Modulation of Long Non-coding RNAs by Different Classes of Secondary Metabolites from Plants: A Mini-review on Antitumor Effects.

The broad pharmacological spectrum of plants is related to their secondary metabolism, which is responsible for the synthesis of different compounds that have multiple effects on cellular physiology. Among the biological effects presented by phytochemicals, their use for the prevention and treatment of cancer can be highlighted. This occurs due to several mechanisms of antitumor action demonstrated by these compounds, including regulation of the cell signaling pathways and inhibition of tumor growth. In this way, long non-coding RNAs (lncRNAs) appear to be promising targets for the treatment of cancer. Their deregulation has already been related to a variety of clinicalpathological parameters. However, the effects of secondary metabolites on lncRNAs are still restricted. For this reason, the present review aimed to gather data on phytochemicals with action on lncRNAs in order to confirm their possible antitumor potential. According to the literature, terpenoid and flavonoid are the main examples of secondary metabolites involved with lncRNAs activity. In addition, the lncRNAs H19, CASC2, HOTAIR, NKILA, CCAT1, MALAT1, AFAP1-AS1, MEG3, and CDKN2B-AS1 can be highlighted as important targets in the search for new anti-tumor agents since they act as modulating pathways related to cell proliferation, cell cycle, apoptosis, cell migration and invasion. Finally, challenges for the use of natural products as a commercial drug were also discussed. The low yield, selectivity index and undesirable pharmacokinetic parameters were emphasized as a difficulty for obtaining these compounds on a large scale and for improving the potency of its biological effect. However, the synthesis and/or development of formulations were suggested as a possible approach to solve these problems. All of these data together confirm the potential of secondary metabolites as a source of new anti-tumor agents acting on lncRNAs.

Brazilian essential oils as source for the discovery of new anti-COVID-19 drug: a review guided by in silico study.

The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in China and its spread worldwide has become one of the biggest health problem due to the lack of knowledge about an effective chemotherapy. Based on the current reality of the SARS-CoV-2 pandemic, this study aimed to make a review literature about potential anti-coronavirus natural compounds guided by an in silico study. In the first step, essential oils from native species found in the Brazilian herbal medicine market and Brazilian species that have already shown antiviral potential were used as source for the literature search and compounds selection. Among these compounds, 184 showed high antiviral potential against rhinovirus or picornavirus by quantitative structure-activity relationship analysis. (E)-α-atlantone; 14-hydroxy-α-muurolene; allo-aromadendrene epoxide; amorpha-4,9-dien-2-ol; aristochene; azulenol; germacrene A; guaia-6,9-diene; hedycaryol; humulene epoxide II; α-amorphene; α-cadinene; α-calacorene and α-muurolene showed by a molecular docking study the best result for four target proteins that are essential for SARS-CoV-2 lifecycle. In addition, other parameters obtained for the selected compounds indicated low toxicity and showed good probability to achieve cell permeability and be used as a drug. These results guided the second literature search which included other species in addition to native Brazilian plants. The majority presence of any of these compounds was reported for essential oils from 45 species. In view of the few studies relating essential oils and antiviral activity, this review is important for future assays against the new coronavirus. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s11101-021-09754-4.

In silico pharmacological prediction and cytotoxicity of flavonoids glycosides identified by UPLC-DAD-ESI-MS/MS in extracts of Humulus lupulus leaves cultivated in Brazil.

Ethanolic (EB) extract and hexanic (SH) and hydromethanolic (SEM) sub-extracts of Humulus lupulus leaves were submitted to cytotoxicity evaluation and to phytochemical methods. The effect of EB and SEM on cellular cycle was evaluated by propidium iodide method and the phases were quantified through flow cytometry. The cytotoxicity assessment was done using T24 and MRC5 cells, with EB and SEM (25-1200 µg/mL). By means of UPLC-DAD-MS/MS data were identified the flavonoids astragaline, nicotiflorin, kaempferol-7-O-rutinoside, robinin, hyperin, rutin, quercetin-7-O-rutinoside and manghaslin. EB (800 µg/mL) and SEM (1200 µg/mL) reduces the T24 cell viability. These extracts at 25 µg/mL stimulate the growth of MRC5 cells, evidencing a selective cytotoxicity. After 24 h of the treatment with extracts was not observed cycle arrest of T24 cells. The bioactivity prediction of the flavonoids was evaluated in silico through in house Active-IT software and PASSonline which indicated potential activity as antitumoral, cytotoxic, anti-inflammatory, antiparasitic, antimicrobial, antiviral and others.

Preparation of glass-ionomer cement containing ethanolic Brazilian pepper extract (Schinus terebinthifolius Raddi) fruits: chemical and biological assays.

Plants may contain beneficial or potentially dangerous substances to humans. This study aimed to prepare and evaluate a new drug delivery system based on a glass-ionomer-Brazilian pepper extract composite, to check for its activity against pathogenic microorganisms of the oral cavity, along with its in vitro biocompatibility. The ethanolic Brazilian pepper extract (BPE), the glass-ionomer cement (GIC) and the composite GIC-BPE were characterized by scanning electron microscopy, attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), and thermal analysis. The BPE compounds were identified by UPLC-QTOF-MS/MS. The release profile of flavonoids and the mechanical properties of the GIC-BPE composite were assessed. The flavonoids were released through a linear mechanism governing the diffusion for the first 48 h, as evidenced by the Mt/M∞ relatively to [Formula: see text], at a diffusion coefficient of 1.406 × 10-6 cm2 s-1. The ATR-FTIR analysis indicated that a chemical bond between the GIC and BPE components may have occurred, but the compressive strength of GIC-BPE does not differ significantly from that of this glass-ionomer. The GIC-BPE sample revealed an ample bacterial activity at non-cytotoxic concentrations for the human fibroblast MRC-5 cells. These results suggest that the prepared composite may represent an alternative agent for endodontic treatment.

Salt-dependent hypertension and inflammation: targeting the gut-brain axis and the immune system with Brazilian green propolis.

Systemic arterial hypertension (SAH) is a major health problem around the world and its development has been associated with exceeding salt consumption by the modern society. The mechanisms by which salt consumption increase blood pressure (BP) involve several homeostatic systems but many details have not yet been fully elucidated. Evidences accumulated over the last 60 decades raised the involvement of the immune system in the hypertension development and opened a range of possibilities for new therapeutic targets. Green propolis is a promising natural product with potent anti-inflammatory properties acting on specific targets, most of them participating in the gut-brain axis of the sodium-dependent hypertension. New anti-hypertensive products reinforce the therapeutic arsenal improving the corollary of choices, especially in those cases where patients are resistant or refractory to conventional therapy. This review sought to bring the newest advances in the field articulating evidences that show a cross-talking between inflammation and the central mechanisms involved with the sodium-dependent hypertension as well as the stablished actions of green propolis and some of its biologically active compounds on the immune cells and cytokines that would be involved with its anti-hypertensive properties.

Herbal medicines to the treatment of skin and soft tissue infections: advantages of the multi-targets action.

The research for new treatments of skin and soft tissue infections (SSTIs) is important due to their high prevalence and number of hospitalizations. The purpose of this review is to address the pathophysiology of SSTIs to highlight the advantages of herbal medicines to their treatment, showing examples of species and compounds with multi-targets action. SSTIs have a complex physiopathology involving the microorganism, as well as inflammation and difficult healing. Therefore, antimicrobial, anti-inflammatory, antioxidant and healing activities are an approach possible for their treatment. Herbal medicines have a wide diversity of biological compounds, mainly phenolic compounds that may act on different targets and also have synergism between them. Therefore, a single medicine may have the four key activities that allied allow eliminating the infection, control the inflammation process and accelerating the healing process, preventing complications with chronic infections.

Anti-inflammatory activity of Protium spruceanum (Benth.) Engler is associated to immunomodulation and enzymes inhibition.

ETHNOPHARMACOLOGICAL RELEVANCE: Protium spruceanum (Burseraceae) is used in Brazilian traditional medicine as anti-inflammatory, but the factors involved in this activity were not yet characterized. AIMS OF THE STUDY: analyze the aspects involved in the anti-inflammatory activity of polar fractions obtained from extracts of leaves and branches. MATERIALS AND METHODS: Hydromethanolic fraction was obtained by liquid-liquid partition from crude ethanolic extract and its compounds were identified by LC-DAD-MS. Activity tests were performed using LPS + IFN-γ stimulated J774A.1 macrophages. Cytokines were evaluated by CBA kit, NO by Griess method, ROS by DCFH-DA, N-acetylglucosaminidase (NAG) activity by spectrophotometric method, matrix-metalloproteinase (MMP-9) activity by zymography, inducible nitric oxide synthase (iNOS) expression by immunofluorescence and cyclooxygenase (COX-2) expression by Western blot. RESULTS: Fractions induced an increase of IL-6 and IL-10 which leads to the control of pro-inflammatory cytokines levels. The treatment with the fractions also reduced NO production at all concentrations tested in all evaluated periods. ROS production by the macrophages was inhibited by the treatment and the leaves fraction showed the best results with a lower concentration than that observed for the branches. The enzymes assays showed that leaves fraction inhibited NAG and MMP-9 activities, as well as, iNOS and COX-2 expression. These activities can be associated with the presence of procyanidin, catechin, rutin, quercitrin, isoquercitrin and kaempferol-3-O-rhamnoside, major compounds that were identified in the fraction. CONCLUSIONS: Anti-inflammatory activity of P. spruceanum is associated to an immunomodulatory effect that leads to inhibition of ROS, NO, NAG, MMP-9, COX-2 and iNOS.

Development of propolis nanoemulsion with antioxidant and antimicrobial activity for use as a potential natural preservative.

Propolis has demonstrated potential use as food preservative but it presents strong and unpleasant flavor that alters the sensory characteristics foods. A nanoemulsion was proposed to carry the Brazilian propolis extracts for use as natural food preservative. Antimicrobial and antioxidant activities and chemical constituents of the extracts were investigated. The latter were made by sequential extraction using different solvents (hexane, ethyl acetate and ethanol). Antimicrobial activity was evaluated by agar diffusion and microdilution methods and antioxidant activity by DPPH and ABTS assays. Extracts showed antibacterial and antioxidant activity, highlighting the ethanolic which contained artepillin-C, kaempferide, drupanin and p-coumaric acid as main compounds by LC-MS analysis. The nanoemulsion developed by phase inversion method was characterized and stable under thermal-stress and centrifugation conditions. Biological properties evaluated were effectively maintained by the formulation. It was concluded that the nanoemulsion can be used as a food preservative, preventing degradation and masking the propolis off-flavor.

Anti-Inflammatory and Antioxidant Properties of Black Mulberry (Morus nigra L.) in a Model of LPS-Induced Sepsis.

Sepsis is a complex disease and is the cause of many deaths worldwide. Sepsis pathogenesis involves a dysregulated inflammatory response with consequent production of inflammatory mediators and reactive species. The production and excessive release of these substances into the systemic circulation trigger various cellular and metabolic alterations that are observed during the disease evolution. Thus, more studies have been carried out to investigate the therapeutic potential of plants such as Morus nigra L., popularly known as black mulberry. Studies have shown that plants belonging to the Morus genus are rich in secondary metabolites such as flavonoids which are associated with important biological activities as antioxidant and anti-inflammatory actions. Based on this context, the objective of our study was to evaluate the anti-inflammatory and antioxidant properties of Morus nigra L. in a sepsis model induced by LPS. Male C57BL/6 mice were distributed in four groups: control, sepsis, sepsis treated with leaf extract of mulberry, and sepsis treated with mulberry pulp. The animals were treated with 100 µL of their respective treatments for twenty-one days. Sepsis was induced at the 21st day with lipopolysaccharide (LPS) by intraperitoneal injection. The animals were euthanized 24 hours after receiving the LPS injection. The data obtained were analyzed in GraphPad Prism 6.0 software. Our results showed that treatment with either extract significantly decreased the number of leukocytes in the bronchoalveolar lavage fluid and serum levels of TNF in septic animals. Regarding the redox status, the treatments significantly decreased the antioxidant activity of the enzyme glutathione peroxidase. Regarding metalloproteinase type 2, it was observed that the treatment with black mulberry pulp was able to significantly reduce the activity of this enzyme concerning the sepsis group. Finally, these results together promoted an increase in the animal's survival that received the black mulberry leaf or pulp extract.

Morus nigra leaf extract improves glycemic response and redox profile in the liver of diabetic rats.

Diabetes mellitus (DM) is a chronic metabolic disorder characterized by hyperglycemia and alterations in the carbohydrate, lipid, and protein metabolism. DM is associated with increased oxidative stress and pancreatic beta cell damage, which impair the production of insulin and the maintenance of normoglycemia. Inhibiting oxidative damage and controlling hyperglycemia are two important strategies for the prevention of diabetes. The pulp and leaf extracts of mulberry (Morus nigra L.) have abundant total phenolics and flavonoids, and its antioxidant potential may be an important factor for modulating oxidative stress induced by diabetes. In this study, DM was induced by intraperitoneal injection of alloxan monohydrate (135 mg kg(-1)). Female Fischer rats were divided into four groups: control, diabetic, diabetic pulp, and diabetic leaf extract. Animals in the diabetic pulp and diabetic leaf extract groups were treated for 30 days with M. nigra L. pulp or leaf extracts, respectively. At the end of treatment, animals were euthanized and, liver and blood samples were collected for analysis of biochemical and metabolic parameters. Our study demonstrated that treatment of diabetic rats with leaf extracts decreased the superoxide dismutase (SOD)/catalase (CAT) ratio and carbonylated protein levels by reducing oxidative stress. Moreover, the leaf extract of M. nigra L. decreased the matrix metalloproteinase (MMP)-2 activity, increased insulinemia, and alleviated hyperglycemia-induced diabetes. In conclusion, our study found that the leaf extract of M. nigra L. improved oxidative stress and complications in diabetic rats, suggesting the utility of this herbal remedy in the prevention and treatment of DM.

Protective effect of Baccharis trimera extract on acute hepatic injury in a model of inflammation induced by acetaminophen.

BACKGROUND: Acetaminophen (APAP) is a commonly used analgesic and antipyretic. When administered in high doses, APAP is a clinical problem in the US and Europe, often resulting in severe liver injury and potentially acute liver failure. Studies have demonstrated that antioxidants and anti-inflammatory agents effectively protect against the acute hepatotoxicity induced by APAP overdose. METHODS: The present study attempted to investigate the protective effect of B. trimera against APAP-induced hepatic damage in rats. The liver-function markers ALT and AST, biomarkers of oxidative stress, antioxidant parameters, and histopathological changes were examined. RESULTS: The pretreatment with B. trimera attenuated serum activities of ALT and AST that were enhanced by administration of APAP. Furthermore, pretreatment with the extract decreases the activity of the enzyme SOD and increases the activity of catalase and the concentration of total glutathione. Histopathological analysis confirmed the alleviation of liver damage and reduced lesions caused by APAP. CONCLUSIONS: The hepatoprotective action of B. trimera extract may rely on its effect on reducing the oxidative stress caused by APAP-induced hepatic damage in a rat model. General Significance. These results make the extract of B. trimera a potential candidate drug capable of protecting the liver against damage caused by APAP overdose.

A non-michaelian behavior of the in vitro metabolism of the pentacyclic triterpene alfa and beta amyrins by employing rat liver microsomes.

Pharmacological studies employing alpha and beta amyrin have demonstrated potential application in several biological activities suggesting their application as promising drugs. In the early drug development, metabolism studies may give important parameters regarding the efficacy and safety of the drug candidate. Therefore, the aim of this work was to determine the enzymatic kinetic parameters of these pentacyclic triterpenes. Chromatographic analyzes were performed using a Shimadzu GC-MS system. The resolution of amyrins was achieved with a DB5-MS column of 0.25 µM film thickness, 30.0 cm length and 0.25 mm diameter. At this condition, the retention times of beta- and alpha-amyrin were 21.3 and 20.2 min, respectively. The proposed method showed to be linear over the concentration range of 0.16-42.18 µM for beta amyrin and 0.11-28.12 µM for alpha amyrin. The lowest concentration quantified by the validated method was 0.16 µM for beta and 0.11 µM for alpha amyrin. The stability study showed that amyrins were stable at room temperature for 12h and at 37°C for 1h. The absolute recovery of the amyrin isomers from the rat microsome was 54.3-59.2%. The enzymatic kinetics presented sigmoidal plots. It was observed a Vmax=0.698 ± 0.022 µmol/mg protein/min, S50=4.4 µM and Hill coefficient of 2.7 ± 0.17 for alpha amyrin and a Vmax=0.775 ± 0.034 µmol/mg protein/min, S50=7.0 µM and Hill coefficient of 2.5 ± 0.21 for beta amyrin. The obtained results give the first clues regarding amyrin metabolism and suggests a more detailed study conducted employing isolated CYP isoforms.

Genotoxic effects of (-)-cubebin in somatic cells of mice.

(-)-Cubebin belongs to the dibenzylbutyrolactone lignan group, which is widely distributed in the plant kingdom. Because this compound shows interesting biological activities, it is extremely important to evaluate its possible genotoxic activity to allow its safe use in humans. Thus, the present study was performed to investigate the genotoxicity potential activity of (-)-cubebin assessed by two assays: micronucleus in bone marrow cells and comet test in peripheral blood leukocytes of Swiss mice. In the (-)-cubebin dose range-finding assays, the maximum tolerated dose was greater than 2000 mg kg(-1) . The compound was administered by an oral route at single doses of 250, 500 and 2000 mg kg(-1) body weight. Cytotoxicity was assessed by scoring 200 consecutive total polychromatic (PCE) and normochromatic (NCE) erythrocytes (PCE/NCE ratio). Under our experimental conditions, micronucleus and comet assays, respectively, showed that (-)-cubebin caused dose-related clastogenic and genotoxic effects in the somatic cells investigated. PCE/NCE ratio showed no cytotoxicity for the three doses of the compound. The data suggest caution in the ingestion of (-)-cubebin by humans, especially at high doses.