Synergistic antimicrobial potential of EGCG and fosfomycin against biofilms associated with endodontic infections

Abstract Objective This study aimed to evaluate the cytotoxicity and synergistic effect of epigallocatechin gallate (EGCG) and fosfomycin (FOSFO) on biofilms of oral bacteria associated with endodontic infections. Methodology This study determined minimum inhibitory and bactericidal concentration (MIC/MBC) and fractionated inhibitory concentration (FIC) of EGCG and FOSFO against Enterococcus faecalis, Actinomyces israelii, Streptococcus mutans, and Fusobacterium nucleatum. Monospecies and multispecies biofilms with those bacteria formed in polystyrene microplates and in radicular dentin blocks of bovine teeth were treated with the compounds and control chlorhexidine (CHX) and evaluated by bacterial counts and microscopy analysis. Toxicity effect of the compounds was determined on fibroblasts culture by methyl tetrazolium assays. Results The combination of EGCG + FOSFO demonstrated synergism against all bacterial species, with an FIC index ranging from 0.35 to 0.5. At the MIC/FIC concentrations, EGCG, FOSFO, and EGCG+FOSFO were not toxic to fibroblasts. EGCG+FOSFO significantly reduced monospecies biofilms of E. faecalis and A. israelli, whereas S. mutans and F. nucleatum biofilms were eliminated by all compounds. Scanning electron microscopy of multispecies biofilms treated with EGCG, EGCG+FOSFO, and CHX at 100x MIC showed evident biofilm disorganization and substantial reduction of extracellular matrix. Confocal microscopy observed a significant reduction of multispecies biofilms formed in dentin tubules with 84.85%, 78.49%, and 50.6% of dead cells for EGCG+FOSFO, EGCG, and CHX at 100x MIC, respectively. Conclusion EGCG and fosfomycin showed a synergistic effect against biofilms of oral pathogens related to root canal infections without causing cytotoxicity.

Preliminary study on high throughput screening small molecules targeting Gram-negative bacilli outer membrane protein BamA / 中华检验医学杂志

Objective:High-throughput screening to obtain small molecular compounds against Gram-negative bacilli by targeting BamA outer membrane protein.Methods:The sybyl-X2.1 software was used to perform high-throughput virtual screening of small molecular compounds in Chemdiv compound library based on the molecular docking. The top 150 hits by high-throughput screening were re-screened through in vitro biological experiments. The top 4 small molecules with obvious antibacterial activity were selected for in-depth molecular docking analysis, and the small molecule 8308-0401 with the highest docking score was selected for further experiments. The antibacterial effect of 8308-0401 combined with rifampicin was tested by checkerboard assay. Finally, the affinity between 8308-0401 and BamA was tested by plasma surface resonance assay. Results:The docking score of the top 150 hits calculated by high-throughput virtual screening had a mean value of 5.63. In vitro biological experiments showed that small molecules 8308-0401, 8365-1335, C066-2507 and L582-0346 exhibited strong antibacterial activity. Among those molecules, 8308-0401 showed the highest molecular docking score, and synergistic antibacterial activity against both types of strains and clinical isolates when combined with rifampicin. 8308-0401 has a strong affinity to BamA with binding a constant of 182 μmol/L. Conclusion:The small molecule 8308-0401 exerts antibacterial activity against Gram negative bacilli by targeting the outer membrane protein BamA.

Clinical effects of Jiakang Pingxiao prescription combined with methiimidazole on hyperthyroidism / 中国基层医药

Objective:To investigate the clinical effects of Jiakang Pingxiao prescription combined with methiimidazole on hyperthyroidism. Methods:A total of 100 patients with hyperthyroidism admitted to Shanxian Central Hospital from February 2018 to January 2021 were included in this study. They were randomly divided into a study group and a control group, with 50 patients in each group. The control group was treated with methiimidazole, and the study group was treated with Jiakang Pingxiao prescription combined with methiimidazole. Thyroid function, serum levels of osteocalcin (OCN), β-CTx, hypersensitive C-reactive protein, and interleukin-6 (IL-6) were compared between the two groups. Results:After treatment, serum levels of thyroid stimulating hormone (TSH), free triiodothyronine (FT3), free thyroxine (FT4) in the study group were (3.10 ± 1.36) mU/L, (5.76 ± 1.25) pmol/L, (15.22 ± 1.95) pmol/L, respectively, which were significantly lower than (4.88 ± 1.47) mU/L, (7.13 ± 1.32) pmol/L, (19.07 ± 2.02) pmol/L in the control group ( t = 5.27, 4.71, 6.29, all P < 0.05). Serum OCN, β-CTx, hS-CRP, and IL-6 in the study group were (17.36 ± 2.62) μg/L, (0.32 ± 0.04) μg/L, (4.07 ± 0.86) mg/L, and (1.38 ± 0.21) pg/L, respectively, which were significantly lower than (26.05 ± 2.88) μg/L, (0.51 ± 0.09) μg/L, (6.23 ± 0.91) mg/L, (1.89 ± 0.28) pg/L in the control group ( t = 12.37, 10.40, 7.39, 8.57, all P < 0.05). The incidence of adverse reactions in the study group was significantly lower than that in the control group [6.00% (3/50) vs. 12.00% (3/50), χ2 = 14.78, P < 0.05). Conclusion:Jikang Pingxiao prescription combined with methiimidazole can effectively reduce the inflammatory responses in patients with hyperthyroidism, inhibit the expression of OCN and β-CTX in the serum, and improve thyroid function. The combined method is scientific and reasonable, and is suitable for clinical application. It has good therapeutic effects on hyperthyroidism and is worthy of clinical promotion.

A Review of Antifungal Activity of Combined Plant Extracts or Plant Exudates from Medicinal Plants either together or with Known Antifungal Agents

Medicinal plants provide humanity with important phytochemical compounds and extracts which are widely used in treatment of many diseases. Fungal infections are one of these diseases which are widely distributed especially in developing countries; medicinal plants are extensively used in developing countries. There are few antifungal agents, most of them are expensive and have many adverse effects, also there is high incidence of drug resistance among some available antifungal agents, hence for these mentioned reasons many people, especially in developing countries, use medicinal plants (either alone, combined together or combined with known antifungal drugs) in treatment of many fungal infections. This rise a new and important issue about plant(s) – plant(s) and plant(s) - drug interactions. The aim of this review is to try to fill the gap in understanding the interactions of plant(s) - plant(s) and plant(s) – drug(s) combinations by providing an overview of some evidence-based researches done in this field, so our review highlights many interactions between medicinal plants constituents with current available antifungal agents, these interactions may be synergistic, additive, indifferent or antagonistic, so, if there is any antagonistic effect, we recommend to avoid using the combination which caused this effect. We collected a lot of studies which studied the interactions between plant(s) (including extracts, isolated active constituents, essential oils, plants latexes and other phytochemicals) used either together or with conventional antifungal agents. This will not only bring about better understanding of both phytochemicals and antifungal activity, but also may help in searching and developing new safely and effective drugs, specially with those combinations which showed synergistic effect.

Evaluation of antihyperlipidemic activity of gugulipid alone and in combination with different dosage of atorvastatin in triton-induced hyperlipidemic rodent model: Exploring a possible synergistic activity

Background: Gugulipid obtained from Commiphora mukul carries a long history of safe and efficacious use in hyperlipidemia as per Ayurvedic literature. Statins like atorvastatin are a highly prescribed hypolipidemic drug but not free from potentially serious adverse effects. Aims and Objectives: The present study was designed to establish antihyperlipidemic activity of gugulipid in triton-induced hyperlipidemic rats in comparison to atorvastatin and simultaneously to explore the combination of gugulipid and atorvastatin for any synergistic activity. Materials and Methods: Male Wistar albino rats (20) were divided equally into vehicle (2% gum acacia) (Group I), gugulipid only 6.75 mg/kgbw (Group II), atorvastatin 7.2 mg/kgbw only (Group III), and gugulipid 6.75 mg/kgbw and atorvastatin in 7.2 mg/kgbw combination (Group IV) in Phase 1 study. In Phase 2, additional three groups were created with five rats in each receiving gugulipid 6.75 mg/kgbw with atorvastatin at 5.4 mg/kgbw, 3.6 mg/kgbw, and 1.8 mg/kgbw dosage, respectively (Groups V–VII). Hyperlipidemia was induced by single intraperitoneal injection (400 mg/kgbw) of triton after 7 days of feeding with respective agents dissolved in vehicle through oral route. Results: Regarding total cholesterol (TC), triglyceride (TG), and low-density lipoprotein (LDL), Gr II was found superior to Gr I but inferior to others (P < 0.01). Gr IV prevented the rise of TC and TG significantly in comparison to Gr V, VI, and VII (P < 0.01) whereas Groups V and VI having non-significant difference in between, both differed significantly (P < 0.01) with Gr VII. Groups IV, V, and VI prevented the rise of serum LDL significantly (P < 0.01) from Group VII. Conclusion: Gugulipid showed significant antihyperlipidemic activity and was found to be optimally efficacious and safe in combination with even reduced dose of atorvastatin.

Lime sulfur to control citrus flat mite and its interactions with the entomopathogenic fungus Lecanicillium muscarium

Lime sulfur is one of the few products indicated to control Brevipalpus yothersi in Brazilian organic citrus orchards. Other strategies, such as the use of entomopathogenic fungi should be evaluated, and Lecanicillium muscarium is one of the basic choices for pest management. Knowledge of the interactions between lime sulfur and this entomopathogen is critical for developing control strategies. With this goal, it was conducted the toxicological characterization of lime sulfur to B. yothersi and the compatibility evaluation with L. muscarium. Finally, the effects of L. muscarium and lime sulfur mixtures on B. yothersi control were evaluated. Product evaluation for B. yothersi was done through direct and residual contact bioassay, and different concentrations of lime sulfur mixed in potato dextrose agar culture medium were used to evaluate compatibility with L. muscarium. Lime sulfur was effective against adults of B. yothersi and caused eggs unviability of up to 71.0%, at a dose of 80 L per 2,000 L of H2O. The lethal concentration (LC50 and LC99) of lime sulfur estimated for mite adults were 246.62 and 858.5 µg of sulfur per mL of H2O (ppm a.i.). Lime sulfur concentrations of 180 to 560 ppm a.i. showed promise for use in combination with L. muscarium. However, concentrations of 1,000 and 5,600 ppm significantly reduced colony size and the number of spores/colony. The mixture of 100 and 180 ppm a.i. of lime sulfur with L. muscarium (108 conidia·mL­1) was not able to reduce the lethal time of entomopathogen on B. yothersi.

Current status of antimicrobial therapy for tuberculosis / 中国基层医药

Multidrug-resistant tuberculosis has a long treatment course and a low sputum-negative conversion rate, which have always been the treatment challenges. New drugs for multidrug-resistant tuberculosis have been constantly explored by scholars worldwide. Multiple antibacterial drugs have been found to have the therapeutic effects on multidrug-resistant tuberculosis. Treatment options that can shorten the duration of tuberculosis are also being explored. Addition of certain antibacterial drugs has been found to shorten the duration of tuberculosis. This paper reviews the effects of antibacterial drugs against tuberculosis.

New possibilities for chromoblastomycosis and phaeohyphomycosis treatment: identification of two compounds from the MMV Pathogen Box® that present synergism with itraconazole

BACKGROUND Black fungi of the Herpotrichiellaceae family are agents of chromoblastomycosis and phaeohyphomycosis. There are few therapeutic options for these infections and it is common to associate antifungal drugs in their treatment. OBJECTIVES To investigate the Medicines for Malaria Venture (MMV) Pathogen Box® for possible compounds presenting synergism with antifungal drugs used to treat black fungal infections. METHODS An initial screening of the Pathogen Box® compounds was performed in combination with itraconazole or terbinafine at sub-inhibitory concentrations against Fonsecaea pedrosoi. Hits were further tested against eight Herpotrichiellaceae using the checkerboard method. FINDINGS No synergism was observed with terbinafine. MMV687273 (SQ109) and MMV688415 showed synergism with itraconazole against F. pedrosoi. Synergism of these compounds was confirmed with some black fungi by the checkerboard method. SQ109 and itraconazole presented synergism for Exophiala dermatitidis, F. pedrosoi, F. monophora and F. nubica, with fungicidal activity for F. pedrosoi and F. monophora. MMV688415 presented synergism with itraconazole only for F. pedrosoi, with fungicidal activity. The synergic compounds had high selectivity index values when combined with itraconazole. MAIN CONCLUSIONS These compounds in combination, particularly SQ109, are promising candidates to treat Fonsecaea spp. and E. dermatitidis infections, which account for most cases of chromoblastomycosis and phaeohyphomycosis.

Orofacial antinociceptive effects of perillyl alcohol associated with codeine and its possible modes of action

Abstract This study evaluated the orofacial antinociceptive effect of (S)-(-)-perillyl alcohol (PA) associated with codeine (C) and investigated the possible molecular anchorage mechanisms of PA. Mice (n = 5 per group) were treated with PA alone and associated with codeine and assigned to the following groups: 75.0 mg/kg PA; 75.0 mg/kg PA + C 30 mg/kg; PA 37.5 mg/kg + C 15.0 mg/kg; C 30.0 mg/kg; and control. Nociception was induced by formalin, capsaicin, and glutamate, and was quantified based on the duration (in seconds) of face grooming. The possible mechanisms of action were evaluated by molecular docking study. In the formalin test, PA75/C30 presented an effect in the neurogenic (p < 0.0001) and inflammatory (p < 0.005) phases. Mice treated with PA75 (p < 0.0001) and PA75/C30 (p < 0.0005) showed a reduced nociceptive behavior in the capsaicin test. Glutamate-induced nociception also was blocked by PA75 (p < 0.0005) and C30 (p < 0.0005). The molecular anchorage analysis indicated high negative binding energy values for the evaluated receptors, especially glutamate receptors (AMPA -79.57 Kcal/mol, mGLUR6 -71.25, and NMDA -66.33 Kcal/mol). PA associated with codeine showed orofacial antinociceptive activity, with theoretical evidence of interaction with glutamate receptors.

Efeitos sinérgicos antimicrobianos da combinação dos extratos de sálvia e alcaçuz sobre cepas clínicas de Enterococcus faecalis e Enterococcus faecium / Synergistic antimicrobial effects of the combination of sage and licorice extracts on clinical strains of Enterococcus faecalis and Enterococcus faecium

A crescente busca pelo conhecimento do potencial biológico presente nas plantas medicinais tem estimulado pesquisas, principalmente no que diz respeito ao potencial antimicrobiano dos extratos de plantas. Entretanto, mais estudos sobre os efeitos sinérgicos da combinação desses extratos são fundamentais para sua maior aplicação clínica. O objetivo desse estudo foi avaliar in vitro os efeitos sinérgicos antimicrobianos das associações dos extratos naturais de Salvia officinalis (S. officinalis) e Glycyrrhiza glabra (G. glabra). Foi realizada a análise antimicrobiana sobre três cepas clínicas de Enterococcus faecalis (E. faecalis), duas cepas clínicas de Enterococcus faecium (E. faecium) e uma cepa padrão de cada espécie. Foram determinadas as Concentração Inibitória Mínima (CIM) e Concentração Microbicida Mínima (CMM) por microdiluição em caldo com semeadura, e Índice de Concentração Inibitória Fracionada (ICIF) pela técnica checkerboard. Para avaliar o efeito combinado dos extratos sobre biofilme foram utilizadas duas combinações dos extratos sobre biofilme formado de E. faecalis e sobre biofilme formado de E. faecium, por dois períodos diferentes: 5 minutos e 24 h, e foram avaliados os valores médios de unidades formadoras de colônias por mililitro (UFC/mL). A análise estatística foi feita aplicando método ANOVA e teste de Tukey ou Kruskall-Wallis e Dunn (significância de 5%). Os extratos de S. officinalis e G. glabra apresentaram concentração microbicida para as cepas avaliadas. A combinação dos extratos apresentou valores indiferentes (ICIF ˃ 0,5 e ≤ 4) para as cepas de E. faecium, e valores indiferentes e sinérgicos (ICIF ≤0,5) para cepas de E. faecalis. Sobre biofilme as duas combinações apresentaram reduções estatisticamente significantes do grupo controle negativo (p < 0,05). Dessa forma concluiu-se que a combinação dos extratos de S. officinalis e G. glabra possui feito sinérgico antimicrobiano contra E. faecalis e atividade antibiofilme contra E. faecalis e E. faecium (AU)

The growing search for knowledge of the biological potential present in medicinal plants has stimulated research, especially with regard to the effective antimicrobial potential of plant extracts, however, further studies on the synergistic effects of the combination of these extracts is essential for their greater clinical application. The aim of this study was to evaluate in vitro the synergistic antimicrobial effects of the association of natural extracts of Salvia officinalis (S. officinalis) and Glycyrrhiza glabra (G. glabra). Antimicrobial analysis was performed on three clinical strains of Enterococcus faecalis (E. faecalis), two clinical strains of Enterococcus faecium (E. faecium) and one standard strain of each species. The Minimum Inhibitory Concentration (MIC) and Minimum Microbicidal Concentration (MMC) were determined by microdilution in broth with seeding, and Fractional Inhibitory Concentration Index by the checkerboard technique. To evaluate the combined effect of extracts on biofilm, two combinations of extracts on biofilm formed by E. faecalis and on biofilm formed by E. faecium were used, for two different periods: 5 min and 24 h, and the mean values of units were evaluated. colony forming agents per milliliter (CFU/mL). Statistical analysis was performed using the ANOVA method and Tukey's or Kruskall-Wallis and Dunn's test (5% significance). The extracts of S. officinalis and G. glabra showed microbicidal concentration for the strains evaluated. The combination of extracts showed indifferent values (FICI ˃ 0.5 and ≤ 4) for E. faecium strains, and indifferent and synergistic values FICI ≤0.5) for E. faecalis strains. On biofilm, the two combinations showed statistically significant reductions compared to the negative control group (p < 0.05). Thus, it is concluded that the combination of extracts of S. officinalis and G. glabra has synergistic antimicrobial effect against E. faecalis and antibiofilm activity against E. faecalis and E. faecium (AU)

Mechanisms underlying synergistic induction and promotion of cutaneous squamous cell carcinoma in nude mice by ultraviolet light and human papillomavirus 16 E6 / 中华皮肤科杂志

Objective:To establish a xenograft model of cutaneous squamous cell carcinoma (CSCC) in nude mice, and to explore mechanisms underlying synergistic induction and promotion of CSCC in nude mice by ultraviolet radiation and human papillomavirus (HPV) infection.Methods:The human CSCC A431 cells were divided into 3 groups, namely HPV16 E6 overexpression group (LV-OE-HPV16 E6 group) transfected with adenovirus-mediated HPV16 E6 gene, empty vector group transfected with empty adenovirus vectors, and blank control group remaining untransfected. Using serum-free Dulbecco′s modified Eagle′s medium (DMEM) , A431 cells in the empty vector group and LV-OE-HPV16 E6 group were prepared into single-cell suspensions, which were subcutaneously inoculated into the left buttocks of SKH-1 nude mice separately, namely empty vector group ( n = 16) and LV-OE-HPV16 E6 group ( n = 16) . Tumor growth was observed and recorded for the mice every 3 days. When the tumor size reached 150 mm 3, the modeling was considered successful. After successful modeling, 8 mice in each group were irradiated with ultraviolet light at a dose of 1 440 mJ·cm -2·d -1 for 12 minutes each time, the other 8 mice in each group received no ultraviolet radiation, that is to say, all the 32 mice were divided into 4 groups: empty vector group, empty vector + UV group, LV-OE-HPV16 E6 group, and LV-OE-HPV16 E6 + UV group. After 4-week radiation, these nude mice were sacrificed, tumor weight and volume were measured, a tumor growth curve was drawn, immunohistochemistry study, Western blot analysis and real-time fluorescence-based quantitative PCR (qRT-PCR) were conducted to determine the protein and mRNA expression of Wnt1 and β-catenin in CSCC tissues collected from nude mice, respectively. For normally distributed measurement data, analysis of variance was used for intergroup comparisons, and least significant difference- t test for multiple comparisons; for non-normally distributed measurement data, rank sum test was used for intergroup comparisons. Results:Compared with the empty vector group (2.20 ± 0.24 g) , the tumor weight significantly increased in the empty vector + UV group (2.90 ± 0.36 g, t = 4.39, P < 0.001) , LV-OE-HPV16 E6 group (3.19 ± 0.32 g, t = 6.77, P < 0.001) , and LV-OE-HPV16 E6 + UV group (4.41 ± 0.18 g, t = 20.11, P < 0.001) ; the tumor volume was also significantly higher in the empty vector + UV group (1 033.12 ± 400.15 mm 3, t = 1.90, P < 0.001) , LV-OE-HPV16 E6 group (1 119.21 ± 447.57 mm 3, t = 2.21, P < 0.001) , and LV-OE-HPV16 E6 + UV group (1 464.29 ± 409.98 mm 3, t = 4.22, P < 0.001) than in the empty vector group (688.94 ± 319.31 mm 3) . Immunohistochemical study showed no significant difference in the protein expression of Wnt1 and β-catenin among the 4 groups ( F = 0.76, 0.71, respectively, both P > 0.05) ; Western blot analysis showed significant differences in the protein expression levels of Wnt1 and β-catenin among the 4 groups ( F = 16.74, 49.90, respectively, both P < 0.05) , which were significantly higher in the LV-OE-HPV16 E6 + UV group than in the empty vector group, empty vector + UV group and LV-OE-HPV16 E6 group (all P < 0.05) . qRT-PCR showed a significant difference in the mRNA expression of Wnt1 and β-catenin among the 4 groups ( F = 7.77, 8.38, respectively, both P<0.05) , and the LV-OE-HPV16 E6 + UV group showed significantly increased Wnt1 mRNA expression levels compared with the empty vector group, empty vector + UV group and LV-OE-HPV16 E6 group (all P < 0.05) . Conclusion:Ultraviolet radiation and HPV infection showed synergistic effect on the induction and promotion of CSCC.

Vascular interactions of Croton schiedeanus major flavonoids in isolated aortic rings from Wistar rats / Interacciones vasculares de los principales flavonoides de Croton schiedeanus en anillos aislados de aorta de ratas Wistar

Background: Ayanin (3,7,4'-Tri-O-methylquercetin) and 3,7-Di-O-methylquercetin (DMQ) are the main active metabolites isolated by bioguided fractionation from Croton schiedeanus, species known popularly in Colombia as "almizclillo", which has been studied in experimental models in rats, exerting vasodilator and antihypertensive effects. Also, when the effect of these flavonoids was studied separately, important vasodilation was observed. Objective:To evaluate whether flavonoids from Croton schiedeanus have synergistic vasodilator properties when different combinations are used in isolated aorta rings. Methods: Cumulative concentrations of ayanin (10-8 M - 6x10-5 M or 0.01 µM - 60 µM) were assayed in the absence and presence of an increasing concentration of 3,7-Di-O-methylquercetin (DMQ) (10-8 ­ 3x10-5M or 0.01­30 µM) in isolated rings from Wistar rats, pre-contracted with phenylephrine. The concentration-response curve with the maximal effect was compared with that obtained by Croton schiedeanus whole ethanolic extract (10-6 ­ 3x10-4 g/mL). Also, this combination was assayed in the presence of the nitric oxide synthetase inhibitor L-NAME (10-4 M) and the guanylate cyclase inhibitor methylene blue (10-4 M) to assess the role of the NO/cGMP pathway in this interaction. Results: Ayanin and DMQ display a dual interaction in vascular relaxant response: agonism at higher concentration ranges (10-6 ­ 3x10-5 M or 1­30 µM) and antagonism at lower concentration ranges (10-8 ­ 3x10-7 M or 0.01­0.3 µM). The efficacy at the highest concentration was greater than that obtained by the whole extract (Emax: 98.4% vs. 33.9%). This response was decreased but not reverted in the presence of L-NAME and methylene blue. Thus, the vasodilator effect of this combination does not depend entirely on the NO/cGMP cyclic pathway. Conclusion: The combined use of appropriate concentrations of these flavonoids could represent an advantage over Croton schiedeanus whole extract for vasodilator purposes

Antecedentes: Ayanina (3,7,4'-Tri-O-metilquercetina) y 3,7-Di-O-metilquercetina (DMQ) son los principales metabolitos activos aislados mediante fraccionamiento bioguiado, a partir de Croton schiedeanus, especie conocida popularmente en Colombia como "almizclillo", la cual ha sido estudiada en modelos experimentales en ratas, ejerciendo efectos antihipertensivos y vasodilatadores. Además, al estudiar por separado el efecto de los flavonoides, se observó importante vasodilatación. Objetivo:Evaluar si los principales flavonoides de Croton schiedeanus tienen propiedades vasodilatadoras sinérgicas al utilizar diferentes combinaciones de ellos en anillos de aorta aislados. Metodología: Se analizaron concentraciones acumulativas de ayanina (10-8 M - 6x10-5 M o 0,01 µM - 60 µM) en ausencia y en presencia de concentraciones crecientes de DMQ (10-8 M - 3x10-5 M o 0,01 µM ­ 30 µM) en anillos aislados de ratas Wistar, pre-contraídos con fenilefrina. La curva concentración respuesta obtenida con el efecto máximo, fue comparada con la obtenida con el extracto etanólico de Croton schiedeanus (10-6 - 3x10-4 g/mL). Adicionalmente, esta combinación fue ensayada en presencia del inhibidor de óxido nítrico sintetasa L-NAME (10-4 M) y el inhibidor de guanilato ciclasa, azul de metileno (10-4 M) para evaluar el papel de la vía NO/GMPc en esta interacción. Resultados: Ayanina y DMQ muestran una interacción dual en la respuesta vascular relajante: agonismo en el rango más alto (10-6 M ­ 3x10-5 M o 1 µM ­ 30 µM), y antagonismo en el rango más bajo (10-8 M ­ 3x10-7 M o 0.01 µM ­ 0,3 µM). A altas concentraciones, la eficacia de los flavonoides fue mayor que las obtenidas por el extracto completo (Emáx: 98,4% vs 33,9%). Esta respuesta disminuyó, pero no se revirtió en presencia de L-NAME y azul de metileno. Por lo tanto, el efecto vasodilatador de esta combinación no depende enteramente de la vía NO/GMPc. Conclusión: El uso combinado de las concentraciones apropiadas de estos flavonoides podría representar una ventaja sobre el extracto de Croton schiedeanus, con propósitos vasodilatadores

ASIC2 Synergizes with TRPV1 in the Mechano-Electrical Transduction of Arterial Baroreceptors / 神经科学通报·英文版

Mechanosensitive ion channels (MSCs) are key molecules in the mechano-electrical transduction of arterial baroreceptors. Among them, acid-sensing ion channel 2 (ASIC2) and transient receptor potential vanilloid subfamily member 1 (TRPV1) have been studied extensively and documented to play important roles. In this study, experiments using aortic arch–aortic nerve preparations isolated from rats revealed that both ASIC2 and TRPV1 are functionally necessary, as blocking either abrogated nearly all pressure-dependent neural discharge. However, whether ASIC2 and TRPV1 work in coordination remained unclear. So we carried out cell-attached patch-clamp recordings in HEK293T cells co-expressing ASIC2 and TRPV1 and found that inhibition of ASIC2 completely blocked stretch-activated currents while inhibition of TRPV1 only partially blocked these currents. Immunofluorescence staining of aortic arch–aortic adventitia from rats showed that ASIC2 and TRPV1 are co-localized in the aortic nerve endings, and co-immunoprecipitation assays confirmed that the two proteins form a compact complex in HEK293T cells and in baroreceptors. Moreover, protein modeling analysis, exogenous co-immunoprecipitation assays, and biotin pull-down assays indicated that ASIC2 and TRPV1 interact directly. In summary, our research suggests that ASIC2 and TRPV1 form a compact complex and function synergistically in the mechano-electrical transduction of arterial baroreceptors. The model of synergism between MSCs may have important biological significance beyond ASIC2 and TRPV1.

In vitro antimicrobial and synergistic effect of essential oil from the red macroalgae Centroceras clavulatum (C. Agardh) Montagne with conventional antibiotics

Objective: To study the chemical profile, antimicrobial properties, and synergistic effect with known antibiotics of essential oil extracted from the marine red macroalgae Centroceras clavulatum (C. Agardh) Montagne, collected in Morocco. Methods: The chemical composition of the oil was analyzed by gas chromatography-mass spectrometry. The oil was evaluated for antibacterial (Pseudomonas aeruginosa, Escherichia coli, Bacillus subtilis, Micrococcus luteus, Staphylococcus aureus, and Klebsiella pneumoniae), and antifungal activity (Candida albicans, Candida glabrata, Candida krusei, and Candida parapsilosis), by the disc diffusion method. The minimum inhibitory and minimum microbicidal concentrations of the oil were determined, as well as the synergistic effects of its application combined with the antibiotics ciprofloxacin and fluconazole, by the checkerboard method. Results: Thirty molecules were identified in the essential oil, comprising 96.27% of the total oil composition. Monoterpenes such as carvacrol (36.06%) were the most abundant compounds, followed by caryophyllene (14.67%), endo-borneol (9.04%), pyroterebic acid (3.23%) and caryophyllene oxide (3.13%). The oil exhibited a moderate antimicrobial activity with inhibition zone diameters ranging from 9.0 to 15.0 mm. The minimum inhibitory concentration values varied between 0.9 and 14.7 mg/mL, and Bacillus subtilis and Escherichia coli were the more sensitive bacteria with 0.9 and 1.9 mg/mL, respectively. The minimum microbicidal concentration values ranged from 0.4 to 14.7 mg/mL. A significant synergic action was observed when the oil was applied in combination with ciprofloxacin and fluconazole, with fractional inhibitory concentration index values ranging from 0.31 to 0.50. Synergy was found in 80% of the combinations and a 2 to 16-fold reduction of antibiotics MIC was observed. Conclusions: Our findings suggest that the essential oil of Centroceras clavulatum should be further appraised for its potential use in the management of multi-drug resistant microorganisms, with the purpose to restore the activity of standard antimicrobial drugs.

Isobolographic analysis reveals antinociceptive synergism between Ph1 recombinant toxin and morphine in a model of cancer pain in C57BL/6J mice

Abstract Background: Phoneutria nigriventer venom contains Ph1. This toxin and its recombinant form have a remarkable analgesic potential that is associated with blockage of voltage-gated calcium channels and TRPA1 receptors. Although morphine is a mainstay drug to treat moderate and severe pain related to cancer, it has serious and dose-limiting side effects. Combining recombinant Ph1 and morphine to treat pain is an interesting approach that has been gaining attention. Therefore, a quantitative and reliable method to establish the strength of the antinociceptive interaction between these two substances is necessary. The present study was designed to investigate the nature of the functional antinociceptive (analgesic) interaction between Ph1 recombinant toxin and morphine in a model of cancer pain. Methods: Melanoma was produced by intraplantar inoculation of B16-F10 cells into the right paw of C57BL/6J mice. Von Frey filaments measured the paw-withdrawal threshold after intrathecal administration of morphine, recombinant Ph1, and their combination. Thermal hyperalgesia was assessed using Hargreaves apparatus. The degree of interaction was evaluated using isobolographic analysis. Spontaneous and forced motor performance was assessed with the open-field and rotarod tests, respectively. Results: Co-administration of recombinant Ph1 and morphine synergistically reverses the melanoma-induced mechanical hyperalgesia. The potency of the mixture, measured as the effective dose to reach 50% of maximum possible effect (MPE) in ameliorating mechanical hyperalgesia, was about twice fold higher than expected if the interaction between morphine and recombinant Ph1 was merely additive. Treatment with the combination at doses necessary to reach 50% of MPE caused no spontaneous nor forced motor alterations. Conclusion: The combinatorial use of recombinant Ph1 and morphine allows significant and effective dose reduction of both agents, which has translational potential for opioid-sparing approaches in pain management related to cancer.

Interaction of acetyl-CoA carboxylase enzyme inhibiting herbicides with auxin herbicides on ryegrass / Interação de herbicidas inibidores da enzima acetil-CoA carboxilase com herbicidas auxínicos sobre azevém

ABSTRACT: This study aimed to evaluate the antagonistic effect of the mixture ofacetyl coenzyme-A carboxylase (ACCase) enzyme inhibiting herbicides and auxin herbicides in Lolium multiflorum and to determine mechanisms to mitigate this possible effect. The first experiments were conducted by associating the herbicide clethodim (108 g a.i. ha−1), quizalofop-p-ethyl (54 g a.i. ha−1), and clethodim + quizalofop-p-ethyl (108+54 g a.i. ha−1) with 2,4-D (1005 g a.e. ha−1) or triclopyr (720 g a.e. ha−1), in addition to the sole application of the respective graminicides. Another experiment included clethodim (54; 81; 108; 162; 216 g a.i. ha−1), quizalofop-p-ethyl (27; 40.5; 54; 81; 108 g a.i. ha−1), and clethodim + quizalofop-p-ethyl (54+27; 81+40.5; 108+54; 162+81; 216+108 g a.i. ha−1) mixed with 2,4-D (1005 g a.e. ha−1), or triclopyr (720 g a.e. ha−1), in addition to the control treatments without herbicide application. In the second experiment, herbicides clethodim (108 g a.i. ha−1), quizalofop-p-ethyl (54 g a.i. ha−1), and clethodim + quizalofop-p-ethyl (108+54 g a.i. ha−1) in combination with the herbicides 2,4-D (1005 g a.e. ha−1) or triclopyr (720 g a.e. ha−1)had malathion (1000 g a.i. ha−1) or glyphosate (720 g a.e. ha−1) mixed, in addition to the sole applications of the graminicides. The herbicide clethodim + quizalofop-p-ethyl did not present an antagonistic interaction with the auxin herbicides, and obtained 85% weed control. To obtain control similar to the sole application of this graminicide, the dose of the herbicide clethodim needs to be increased by 20%. However, the mixture of the herbicide quizalofop-p-ethyl with 2,4-D and triclopyr affects the ryegrass control. The use of strategies that increase the absorption of ACCase herbicides or the inhibition of P450 enzymes are ways to mitigate the antagonistic effect caused by the association of the two auxin herbicides.

RESUMO: O objetivo do trabalho foi avaliar o efeito antagônico da mistura de herbicidas inibidores da enzima ACCase e herbicidas auxínicos em Lolium multiflorum e determinar mecanismos de mitigação deste possível efeito. No primeiro momento foram conduzidos experimentos associando o herbicida clethodim (108 g i.a. ha-1), quizalofop-p-ethyl (54 g i.a. ha-1) e clethodim + quizalofop-p-ethyl (108 + 54 g i.a. ha-1) com 2,4-D (1005 g e.a. ha-1) ou triclopyr (720 g e.a. ha-1), além da aplicação isolada dos respectivos graminicidas. Outro experimento contou com clethodim (54; 81; 108; 162; 216 g i.a ha-1), quizalofop-p-ethyl (27; 40,50; 54; 81; 108 g i.a ha-1) e clethodim + quizalofop-p-ethyl (54 + 27; 81 + 40,50; 108 +54; 162 +81; 216 + 108 g i.a ha-1) em mistura com 2,4-D (1005 g e.a ha-1) ou triclopyr (720 g e.a. ha-1), além das testemunhas sem aplicação herbicida. No segundo momento os herbicidas clethodim (108 g i.a. ha-1), quizalofop-p-ethyl (54 g i.a. ha-1) e clethodim + quizalofop-p-ethyl (108 + 54 g i.a. ha-1) em associação com os herbicidas 2,4-D (1005 g e.a ha-1) ou triclopyr (720 g e.a. ha-1), contaram com adição de malathion (1000 g i.a. ha-1) ou glyphosate (720 g e.a. ha-1), além das aplicações isoladas dos graminicidas. O herbicida clethodim + quizalofop-p-ethyl não apresentou interação antagônica com os herbicidas auxínicos, obtendo controle de 85%. Já para o herbicida clethodim é necessário o aumento de dose em 20 % é capaz de obter controle similar a aplicação isolada deste graminicida. Porém para o herbicida quizalofop-p-ethyl a mistura com os herbicidas 2,4-D e triclopyr repercute na diminuição do controle do azevém. O uso de estratégias que aumente a absorção do herbicida inibidor de ACCase ou a inibição das enzimas P450 são formas de mitigar o efeito antagônico causado pela associação destes dois tipos de herbicidas.

Atividades farmacológicas da manteiga de bacuri (Platonia insignis Mart): revisão integrativa / Pharmacological actions of bacuri butter (Platonia insignis Mart): an integrative review

RESUMO Objetivo identificar as atividades farmacológicas da manteiga de bacuri (Platonia insignis Mart.). Métodos revisão integrativa, realizada nas bases de dados Literatura Latino-americana e do Caribe em Ciências da Saúde, Cumulative Index to Nursing and Allied Health Literature, EMBASE, MEDLINE/PubMed, Web of Science, Cochrane Library e SCOPUS, sem delimitação temporal e de idioma. A seleção se constituiu de 13 ensaios pré-clínicos. A avaliação das informações ocorreu de forma descritiva, confrontando com os achados pertinentes. Resultados observou-se que 50,0% das publicações foram indexadas na MEDLINE/PubMed, maioria das publicações ocorreram na Inglaterra (61,5%), seguidas do Brasil e dos Estados Unidos, ambos com 13,3%. Destaca-se que 100,0% dos artigos foram ensaios pré-clínicos; atividades farmacológicas para antioxidante (38,4%) e antileishmanicidas (30,7%). Registrou-se que 38,4% dos ensaios apresentaram testes de toxicidade. Conclusão a manteiga de bacuri (Platonia insignis Mart.) apresentou atividades farmacológicas em ensaios pré-clínicos, como antioxidantes, antileshimaniose, anticonvulsivante e cicatrização de feridas.

ABSTRACT Objective to identify the pharmacological activities of bacuri butter (Platonia insignis Mart.). Methods an integrative review, carried out in the databases of Latin American and Caribbean Literature in Health Sciences, Cumulative Index to Nursing and Allied Health Literature, EMBASE, MEDLINE/PubMed, Web of Science, Cochrane Library and SCOPUS, without the time and language restriction. The selection consisted of 13 pre-clinical trials. The information assessment descriptively took place, comparing with the pertinent findings. Results it was observed that 50.0% of the publications were indexed in MEDLINE/PubMed, most publications were from England (61.5%), followed by Brazil and the United States, both with 13.3%. It is noteworthy that 100.0% of the articles were pre-clinical trials; pharmacological activities for antioxidants (38.4%) and antileishmanicides (30.7%). It was found that 38.4% of the trials presented toxicity tests. Conclusion bacuri butter (Platonia insignis Mart.) Showed pharmacological activities in pre-clinical trials, such as antioxidants, antileshimaniasis, anticonvulsant and wound healing.

Self-assembly performance of triterpene natural small molecules and their application in synergistic antitumor chemotherapy / 药学学报

Natural biocompatible nanomaterials such as self-assembled triterpene natural small molecule products with favorable anticancer activity show great potential for biomedical application. However, the mechanisms of their molecular self-assembled structures have not been investigated systematically, while there are still few reports of the natural active carrier for drug delivery. Herein, in this work, we further explored the molecular assembly mechanism and common regularity of tetracyclic triterpenes ergosterol, stigmasterol as well as pentacyclic triterpenes glycyrrhetinic acid and ursolic acid, which suggested that the coplanarity and orderliness of molecular arrangements which are speculated to be responsible for their self-assembly into the spherical, rod-like or lamellar nanostructure. Besides, ergosterol (ET) with better anticancer activity was chosen as a representative substance for construction of the synergistic antitumor nanodrug. By intermolecular hydrogen bonding and π-π stacking, chemotherapeutic drug paclitaxel (PTX) was encapsulated into ET-PTX NPs successfully. Then, the anti-cancer efficacy of the tumor-bearing mice was evaluated according to the protocol approved by the Experimental Animal Research Center of Harbin Medical University. The resulting nanodrug exhibited excellent biosafety and enhanced in vivo anticancer activity efficiency of 52.3%, higher than free PTX (29.4%) or ET NPs (32.5%) alone, further verifying the potential medical application value of triterpene natural products. This work provides not only a theoretical basis for exploring the self-assembly behavior of small molecule natural products, but also a promising perspective for the fabrication of active natural biocompatible nanodrug delivery systems for synergistic antitumor therapy and other biomedical applications.

ASIC2 Synergizes with TRPV1 in the Mechano-Electrical Transduction of Arterial Baroreceptors / 神经科学通报·英文版

Mechanosensitive ion channels (MSCs) are key molecules in the mechano-electrical transduction of arterial baroreceptors. Among them, acid-sensing ion channel 2 (ASIC2) and transient receptor potential vanilloid subfamily member 1 (TRPV1) have been studied extensively and documented to play important roles. In this study, experiments using aortic arch-aortic nerve preparations isolated from rats revealed that both ASIC2 and TRPV1 are functionally necessary, as blocking either abrogated nearly all pressure-dependent neural discharge. However, whether ASIC2 and TRPV1 work in coordination remained unclear. So we carried out cell-attached patch-clamp recordings in HEK293T cells co-expressing ASIC2 and TRPV1 and found that inhibition of ASIC2 completely blocked stretch-activated currents while inhibition of TRPV1 only partially blocked these currents. Immunofluorescence staining of aortic arch-aortic adventitia from rats showed that ASIC2 and TRPV1 are co-localized in the aortic nerve endings, and co-immunoprecipitation assays confirmed that the two proteins form a compact complex in HEK293T cells and in baroreceptors. Moreover, protein modeling analysis, exogenous co-immunoprecipitation assays, and biotin pull-down assays indicated that ASIC2 and TRPV1 interact directly. In summary, our research suggests that ASIC2 and TRPV1 form a compact complex and function synergistically in the mechano-electrical transduction of arterial baroreceptors. The model of synergism between MSCs may have important biological significance beyond ASIC2 and TRPV1.

Cognition of traditional Chinese medicine properties and thinking of clinical rational use of drug / 中国中药杂志

This paper discusses the rational use of traditional Chinese medicine based on chemical composition, body state and biological effect. The essence and connotations of traditional Chinese medicine are explained by modern scientific theory and technical means, and the mechanism of traditional Chinese medicine in the treatment of diseases is defined in modern medicine language, which is conducive to promoting rational and safe clinical use of drugs. Based on the chemical composition of traditional Chinese medicine,the selected genuine medicinal materials were collected and processed in a standardized way, and then used in the combination with other traditional Chinese medicines, with the aim to improve the efficacy of traditional Chinese medicine in clinical indications, increase the advantages, eliminate the disadvantages, and adapt to flexible and safe clinical drug demands. Based on the body state elements, clinical diagnosis and treatment shall be patient-centered, and doctors shall distinguish the differences of pathogenesis, symptoms and diseases, and consider the drug contraindications of special groups. According to the " dose-effect-toxicity" relationship, doctors shall select the appropriate dosage form, control the drug dosage, balance the benefits and risks of drugs, and carry out appropriate medical treatment. Based on the biological effect elements and the regulatory mechanism of traditional Chinese medicine on the target and pathway of disease, traditional Chinese medicine shall strengthen the precise positioning, provide accurate treatment; evaluate the safety of traditional Chinese medicine combination, explore the adverse reaction mechanism, strengthen the clinical safety monitoring of traditional Chinese medicine, and guide the clinical rational use of drugs, in the expectation of ensuring the safe use of traditional Chinese medicine and maximize the clinical efficacy of traditional Chinese medicine.