Ação antifúngica e potencial antibiofilme de diferentes terapias alternativas frente a leveduras do gênero candida / Antifungal action and antibiofilm potential of different alternative therapies against yeasts of the genus candida

As candidoses usualmente são tratadas com antifúngicos. No entanto, o efeito desses fármacos é usualmente comprometido pela resistência microbiana e pelos efeitos adversos ocasionados. Nesse sentido, o aumento da prevalência e a complexidade de microrganismos multirresistentes a antimicrobianos têm incitado a busca por terapias complementares e alternativas capazes de atuar efetivamente frente à resistência emergente aos medicamentos. Diante disso, o objetivo desse trabalho foi avaliar comparativamente a ação antimicrobiana e o potencial antibiofilme, in vitro, entre a terapia fotodinâmica antimirobiana (TFDA) com azul de metileno, a fitoterapia, utilizando o extrato hidroetanólico de Spondias mombin L (EHSM), e o probiótico Lactobacillus rhamnosus (PLR) no controle de leveduras do gênero Candida, sendo elas: Candida albicans, Candida tropicalis e Candida parapsilosis. Trata-se de um estudo experimental, in vitro, analítico e quantitativo, em que foram investigadas, em triplicata, a atividade inibidora do crescimento microbiano e a atividade antibiofilme das seguintes terapias alternativas: TFDA, EHSM e PLR, utilizando como controle positivo a Nistatina 100.000UI/mL. Quanto à análise estatística, além da interpretação descritiva, foi aplicado o teste Two-Way ANOVA e o Teste de Tukey. Dessa forma, observou-se que todas as terapias testadas exibiram atividades antifúngica e antibiofilme. Todavia, quando comparadas tais atividades entre elas e ainda com a Nistatina, verificou-se que: a TFDA apresentou a maior atividade inibitória de crescimento microbiano (p<0,05), semelhante a Nistatina, seguida pelo EHSM, exibindo o PLR a menor atividade antifúngica e a TFDA juntamente com o EHSM representaram as terapias com maior atividade antibiofilme (p<0,0001), atuando ambas de forma semelhante a Nistatina. Nesse sentido, foi possível concluir que todas as terapias estudadas possuem atividades antifúngica e antibiofilme frente às cepas do gênero Candida testadas, com destaque para a atividade inibidora de crescimento microbiano da TFDA e a atividade antibiofilme da TFDA e do EHSM, sendo tais atividades semelhantes às atividades da Nistatina (AU).

Candidoses are usually treated with antifungals. However, the effect of these drugs is usually compromised by microbial resistance and adverse effects. In this sense, the increase in the prevalence and complexity of multidrug-resistant microorganisms to antimicrobials have incited the search for complementary and alternative therapies capable of acting effectively against the emerging resistance to medicines. Therefore, the objective of this study was to comparatively evaluate the antimicrobial action and antibiofilm potential, in vitro, between antimyrobial photodynamic therapy (PDT) with methylene blue, phytotherapy, using hydroethanolic extract of Spondias mombin L (EHSM)and the probiotic Lactobacillus rhamnosus (PLR) in the control of yeasts of the genus Candida: Candida albicans, Candida tropicalis and Candida parapsilosis. This is an experimental, in vitro, analytical and quantitative study in which the inhibitory activity of microbial growth and antibiofilm activity of the following alternative therapies were investigated in triplicate: TFDA, EHSM and PLR, using 100.000UI/mL as positive control. Regarding the statistical analysis, in addition to the descriptive interpretation, the Two-Way ANOVA test and the Tukey test were applied. Thus, it was observed that all therapies tested exhibited antifungal and antibiofilm activities. However, when comparing these activities between them and still with Nystatin, it was found that: TFDA showed the highest inhibitory activity of microbial growth (p <0.05), similar to Nystatin, followed by the EHSM, exhibiting the PLR the lowest antifungal activity and the TFDA together with the EHSM represented the therapies with higher antibiofilm activity (p <0.0001), acting both similarly to Nystatin. In this sense, it was possible to conclude that all the therapies studied have antifungal and antibiofilm activities against the strains of the genus Candida tested, especially the inhibitory activity of microbial growth of TFDA and the antibiofilm activity of TFDA and EHSM, similar to the activities of Nistatina (AU).

A Paradigm Shift in the Development of Anti-Candida Drugs.

BACKGROUND: The considerable increase in the incidence of Candida infection in recent times has prompted the use of numerous antifungal agents, which has resulted in the development of resistance towards various antifungal agents. With rising Candida infections, the need for design and development of novel antifungal agents is in great demand. However, new therapeutic approaches are very essential in preventing the mortality rate and improving the patient outcome in those suffering from Candida infections. OBJECTIVE: The present review objective is to describe the burden, types of Candidiasis, mechanism of action of antifungal agents and its resistance and the current novel approaches used to combat candidiasis. METHODS: We have collected and analyzed 135 different peer-reviewed literature studies pertinent to candidiasis. In this review, we have compiled the major findings from these studies. RESULTS AND CONCLUSION: The review describes the concerns related to candidiasis, its current treatment strategy, resistance mechanisms and imminent ways to tackle the problem. The review explored that natural plant extracts and essential oils could act as sources of newer therapeutic agents, however, the focus was on novel strategies, such as combinational therapy, new antibodies, utilization of photodynamic therapy and adaptive transfer primed immune cells with emphasis on the development of effective vaccination.

Enhanced Killing of Candida krusei by Polymorphonuclear Leucocytes in the Presence of Subinhibitory Concentrations of Melaleuca alternifolia and "Mentha of Pancalieri" Essential Oils.

The aim of this study was to evaluate the influence of tea tree oil (TTO) and "Mentha of Pancalieri" essential oil (MPP) on intracellular killing of Candida krusei, often resistant to conventional drugs, by polymorphonuclear leucocytes (PMNs). Intracellular killing was investigated by incubating yeasts and PMNs with essential oils (EOs) at 1/4 and 1/8 × MIC (Minimal Inhibitory Concentration), in comparison with anidulafungin, used as a reference drug. Killing values were expressed as Survival Index (SI) values. The cytotoxicity of EOs was evaluated by 3-[4,-5-dimethylthiazole-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay. Both EOs were more efficaceous at 1/8 × MIC than 1/4 × MIC, with killing values higher than observed in EO-free systems and in presence of anidulafungin, indicating that the decreasing concentrations did not cause lower candidacidal activity. This better activity at 1/8 × MIC is probably due to the EOs' toxicity at 1/4 × MIC, suggesting that at higher concentrations EOs might interfere with PMNs functionality. TTO and MPP at 1/8 × MIC significantly increased intracellular killing by PMNs through their direct action on the yeasts (both EOs) or on phagocytic cells (MPP), suggesting a positive interaction between EOs and PMNs to eradicate intracellular C. krusei. These data showed a promising potential application of TTO and "Mentha of Pancalieri" EO as natural adjuvants in C. krusei infection management.

Are new variants of psoriasis therapy (IL-17 inhibitors) safe?

Psoriasis is a chronic, recurrent, inflammatory, and proliferative skin disease. Its etiology has not yet been fully assessed, but undoubtedly it is a multifaceted disease. The key role in its pathomechanism is played by genetic, immunologic, and environmental factors and stress. If traditional methods of psoriasis treatment (phototherapy, methotrexate, retinoids, cyclosporine A) fail, we reach for the following biopharmaceuticals - infliximab, etanercept, adalimumab, or ustekinumab. However, genetic engineering progress discovers new possibilities - the pending clinical trials involve IL-17, IL-23 antagonists, PDE4 and -3 and -1. Psoriasis etiopathogenesis mainly involves the IL-17A, IL-17F, and IL-17A/F subtypes, which affect the keratinocytes. The biological therapy molecularly oriented with the antagonists of interleukin 17 is based mainly on the influence onto the cytokine in the manner that prevents it from binding with the receptor. Three biopharmaceuticals are currently under third phase studies: two fully humanized antibodies neutralizing IL-17 - ixekizumab and secukinumab, and one human monoclonal antibody, brodalumab. The below work will be devoted to the analysis of possible undesirable symptoms, which were observed during the studies. We will try to review the latest literature concerning the most important clinical trials conducted in many centers.

Antifungal effect of sesame medicinal herb on Candida Species: original study and mini-review

The aim of this study was to evaluate the antifungal susceptibility patterns of three antifungals, methanolic extracts and N-hexane oil of sesame seeds on C. albicans and C. glabrata, isolated from oral cavity of liver transplant recipients. The results were compared with other reports to develop a mini review as well. Candida species were isolated from liver transplant recipients. To evaluate the antifungal activity of sesame seed oil and methanolic extract, fluconazole, caspofungin and nystatin, the corresponding minimum inhibitory concentrations were determined by CLSI M27-A3 standard method. Minimum fungicidal concentration was also evaluated. The most prevalent species was C. albicans, followed by C. glabrata. Findings indicated sensitivity to antifungal agents and resistance to methanolic extract and N-hexane oil for all C. albicans and C. glabrata isolates. The rate of Candida colonization in the oral cavity of liver transplant recipients was high. Our results revealed that the methanolic and N-hexan extracts of sesame seeds are not effective on C. albicans and C. glabrata species, isolated from the patients. The sesame seed oil pulling and mouthwash cannot effectively cleanse and remove the Candida species in the mouth. Investigation of other medicinal plants or other parts of sesame like leaves and roots are suggested.

Future therapies targeted towards eliminating Candida biofilms and associated infections.

INTRODUCTION: Candida species are common human commensals and cause either superficial or invasive opportunistic infections. The biofilm form of candida as opposed to its suspended, planktonic form, is predominantly associated with these infections. Alternative or adjunctive therapies are urgently needed to manage Candida infections as the currently available short arsenal of antifungal drugs has been compromised due to their systemic toxicity, cross-reactivity with other drugs, and above all, by the emergence of drug-resistant Candida species due to irrational drug use. Areas covered: Combination anti-Candida therapies, antifungal lock therapy, denture cleansers, and mouth rinses have all been proposed as alternatives for disrupting candidal biofilms on different substrates. Other suggested approaches for the management of candidiasis include the use of natural compounds, such as probiotics, plants extracts and oils, antifungal quorum sensing molecules, anti-Candida antibodies and vaccines, cytokine therapy, transfer of primed immune cells, photodynamic therapy, and nanoparticles. Expert commentary: The sparsity of currently available antifungals and the plethora of proposed anti-candidal therapies is a distinct indication of the urgent necessity to develop efficacious therapies for candidal infections. Alternative drug delivery approaches, such as probiotics, reviewed here is likely to be a reality in clinical settings in the not too distant future.

Systems biology of host-fungus interactions: turning complexity into simplicity.

Modeling interactions between fungi and their hosts at the systems level requires a molecular understanding both of how the host orchestrates immune surveillance and tolerance, and how this activation, in turn, affects fungal adaptation and survival. The transition from the commensal to pathogenic state, and the co-evolution of fungal strains within their hosts, necessitates the molecular dissection of fungal traits responsible for these interactions. There has been a dramatic increase in publically available genome-wide resources addressing fungal pathophysiology and host-fungal immunology. The integration of these existing data and emerging large-scale technologies addressing host-pathogen interactions requires novel tools to connect genome-wide data sets and theoretical approaches with experimental validation so as to identify inherent and emerging properties of host-pathogen relationships and to obtain a holistic view of infectious processes. If successful, a better understanding of the immune response in health and microbial diseases will eventually emerge and pave the way for improved therapies.

Characterization of blood beta-1,3-glucan and anti-beta-glucan antibody in hemodialysis patients using culinary-medicinal Royal Sun Agaricus, Agaricus brasiliensis S. Wasser et al. (Agaricomycetideae).

Beta-glucan is a major component of fungal cell walls and shows various immunopharmacological activities including antitumor activity. Previously, we detected anti-beta-glucan antibody in human sera. Anti-beta-glucan antibody participates in the immune response to fungal cell wall beta-glucan. Patients on dialysis are at high risk of infection including fungal infections. We examined the plasma beta-glucan level and the titer of anti-beta-glucan antibody in dialysis patients. We measured plasma beta-1,3-glucan concentrations with the limulus G test and anti-beta-glucan antibody titers by ELISA with Candida beta-glucan-coated plates. We also examined the influence of the period of dialysis and the kind of dialysis membrane. The patients were positive for beta-1,3-glucan in their plasma. The anti-beta-glucan antibody titer was lower in the dialysis patients than in healthy volunteers. Long-term dialysis patients showed lower anti-beta-glucan antibody titers than short-term dialysis patients. No significant difference was found between the kinds of dialysis membrane. The titer of anti-beta-glucan antibody as recognition molecule of beta-glucan was low in dialysis patients compared with healthy volunteers. This is likely to be one factor explaining the sensitivity to infection of the dialysis patients. An appropriate application of culinary-medicinal mushroom such as Agaricus brasiliensis has potential for the prevention of fungal infection in dialysis patients.

Associations of age and birth cohort with total and specific IgE antibody levels.

BACKGROUND: Total and antigen-specific IgE levels vary greatly with age; however, it is unclear whether they are more closely related to patient age or birth cohort. OBJECTIVE: To determine whether birth cohort or age was more strongly correlated with total and specific IgE levels. METHODS: We retrospectively examined the medical records of 5136 asthma patients who were treated at the Niigata Allergic Disease Research Institute Outpatient Clinic during the period from 1997 to 2005. The subjects were divided into four birth cohorts based on their year of birth: the first cohort was born in 1935 or earlier, the second in 1936-1955, the third in 1956-1975, and the fourth in 1976 or later. Their total IgE level and mite-, cedar-, and Candida albicans (Candida)-specific IgE levels were measured using the CAP RAST fluoroenzyme immunoassay test. RESULTS: Univariate analysis revealed that total IgE level and mite-, cedar-, and Candida-specific IgE levels significantly decreased (p < .001) with advancing age. In addition, there were significantly higher IgE levels in later birth cohorts (p < .01). On multivariate analysis, there were associations of total IgE level and mite- and cedar-specific IgE levels with both age and birth cohort. However, there was no significant association between Candida-specific IgE antibody level and either age or birth cohort. CONCLUSIONS: The associations of total and specific IgE levels with age and birth cohort were different. Thus, in comparing the results of IgE antibody testing done in different years, even for patients of the same age, the possibility of a birth cohort effect on IgE levels should be considered.

Atividade antifúngica in vitro do extrato da Uncaria Tomentosa L. (unha de gato) sobre cepas do gênero Candida / In vitro antifungic activity of Uncaria Tomentosa L. (cat's claw) against Candida

Objetivo: O objetivo deste estudo foi avaliar in vitro a ação antifúngica do extrato hidroalcóolico da Uncaria tomentosa L. (unha de gato) sobre cepas padrão de Candida albicans ATCC 36.232, Candida guilliermondii ATCC 6.260, Candida krusei ATCC 34.135 e Candida tropicalis ATCC 13.803, responsáveis por afecções bucais conhecidas por candidíases, ou candioses. Métodos: O material botânico utilizado para os testes foram o micropulverizado do caule da Uncaria tomentosa L., que em seguida foi submetido ao processo de maceração para preparação do extrato. Foram utilizadas linhagens padronizadas de microrganismos Candida (ATCC), obtidas mediante solicitação na Fundação Oswaldo Cruz, Rio de Janeiro. A atividade antimicrobiana e determinação da Concentração Inibitória Mínima (CIM) do extrato da Uncaria tomentosa L. foi determinada através da técnica de ágar-difusão em placas de Petri, meio sólido Agar Mueller Hington - DIFCO. Os mesmos procedimentos foram realizados com a clorexidina em concentração 0,12%, um anti-séptico oral utilizado como controle positivo nos experimentos. Resultados: Todas as espécies avaliadas apresentaram-se sensíveis ao extrato da Uncaria tomentosa L., atuando de forma semelhante à ação da clorexidina (controle positivo). As cepas apresentaram halos de inibição de crescimento até a diluição de 1:16 do extrato. Candida albicans foi o microorganismo que apresentou maior sensibilidade ao extrato da Uncaria tomentosa L., seguido de Candida guilliermondii, Candida krusei e Candida tropicalis. Conclusão: Os resultados deste estudo demonstram que a Uncaria tomentosa L., conhecida popularmente como unha de gato, possui compostos bioativos com atividade antimicrobiana sobre fungos do gênero candida, responsáveis pelas manifestações de candidíase bucal.

Objective: The aim of this study was to evaluate in vitro the antifungal effect of the hydroalcoholic extract of Uncaria tomentosa L. (Cat's Claw) on strains of Candida albicans ATCC 36232, Candida guilliermondii ATCC 6260, Candida krusei ATCC 34135 and Candida tropicalis ATCC 13 803, responsible for oral diseases known as candidiasis or candioses. Methods: The botanical material used in the tests were sputtered from the stem of Uncaria tomentosa L., which was then subjected to the maceration process for preparing the extract. We used standardized strains of Candida microorganisms (ATCC), obtained upon request at the Oswaldo Cruz Foundation, Rio de Janeiro. The antimicrobial activity and determination of Minimum Inhibitory Concentration (MIC) of the extract of Uncaria tomentosa L. was determined by agar-diffusion technique in Petri dishes, solid Mueller Hinton Agar - DIFCO. The same procedures were performed with the 0.12% chlorhexidine, an antiseptic used as positive control in the experiments. Results: All species evaluated were sensitive to the extract of Uncaria tomentosa L., operating similarly to the action of chlorhexidine (positive control). The strains showed inhibition zones of growth until the 1:16 dilution of the extract. Candida albicans was the microorganism that showed greater sensitivity to the extract of Uncaria tomentosa L., followed by Candida guilliermondii, Candida krusei and Candida tropicalis. Conclusion: The results of this study show that Uncaria tomentosa L., popularly known as cat's claw, has bioactive compounds with antimicrobial activity against fungi of the genus Candida are responsible for the manifestations of oral candidiasis.

Veronate (Inhibitex).

Inhibitex, under license from BioResearch, is developing Veronate, an antibody-based immunotherapy for the potential prevention of Staphylococcus epidermidis, Staphylococcus aureus and Candida infections in very-low-birth-weight infants. Phase III clinical trials of Veronate are ongoing.

Atividade antifúngica in vitro da casca do anacardium occidentale linn. sobre leveduras do gênero candida / In vitro antifungal activity of anacardium occidentale linn. bark upon leavens of the candida gender

Os fungos fazem parte da microbiota normal da boca e variações qualitativas e quantitativas destes são encontrados em indivíduos saudáveis. A candidose é uma infecção endógena de ocorrência bastante comum na cavidade bucal provocada por parasitismo ocasional desenvolvido por leveduras do gênero Candida. A utilização das plantas pela medicina popular, seu uso na odontologia e a divulgação dos êxitos conduziram a exploração científica, proporcionando um conhecimento químico-farmacológico de milhares de plantas...

The effect of zinc-supplemented bread consumption on school children with asymptomatic zinc deficiency.

BACKGROUND: Zinc deficiency has been seen in developing countries in which grain-based vegetable protein is consumed more often than animal protein. This study was done to emphasize the importance of zinc-fortified foods and to investigate bioavailability of zinc in zinc-fortified bread. METHODS: Serum zinc concentrations in healthy 7- to 11-year-old school children were determined. In 24 of 101 children serum zinc concentrations were below 65 micrograms/ul. These 24 children with asymptomatic zinc deficiency were divided into two equal groups. The 12 children with low serum zinc concentrations received the zinc-fortified bread providing 2 mg/kg/day elemental zinc acetate for 90 days (zinc-supplemented group), whereas the other 12 children received the same quality bread with no zinc fortification (control group). RESULTS: By the end of the period, the zinc-supplemented group had significantly higher serum and leukocyte zinc concentrations (p < 0.01) and the weight, serum albumin levels, and alkaline phosphatase increased (p < 0.01). Immune functions improved, evidenced by conversion of delayed hypersensitivity skin reactions. Zinc-fortified bread (2 mg/kg/day) caused no side effects or manifestations of zinc toxicity. CONCLUSIONS: The results indicate that the bioavailability of zinc in the bread is satisfactory. The use of zinc-fortified bread was found to be an economical and readily accessible method to eliminate zinc deficiency and to prevent further occurrence.

Effect of experimental selenium deficiency and its supplementation on the candidacidal activity of neutrophils in albino rats.

The role of selenium in the diet of rats has been examined with respect to the neutrophil functions. Feeding of Se-deficient diet for 75 days resulted in reduction in candidacidal activity, superoxide production, oxygen consumption, glucose utilisation and glutathione peroxidase activity. Supplementing the diet with Se for 30 days resulted in partial restoration of all the activities.

Effects of diets of high sulphur content and varied concentrations of copper, molybdenum and thiamine on in vitro phagocytic and candidacidal activity of neutrophils in sheep.

Candidacidal and phagocytic tests were performed on 34 female sheep fed high sulphur diets containing varied concentrations of thiamine, copper, and molybdenum for 14 weeks. Tests were conducted at weekly intervals for five weeks during the latter half of the experiment. The ability of polymorphonuclear leucocytes from sheep on diets unsupplemented with thiamine to kill phagocytosed Candida albicans was lower than those on diets supplemented with thiamine. The ability of polymorphonuclear leucocytes to phagocytose C albicans was lower in animals on low copper diets than in animals on high copper diets. Factorial analysis showed that thiamine supplementation significantly increased (P less than 0.0001) candidacidal but not phagocytic activity. By contrast, copper supplementation significantly increased (P less than 0.0005) the phagocytic activity with no effect on candidacidal activity. The observed detrimental effect of high sulphur intake on in vitro polymorphonuclear leucocyte function can mean that ruminants in areas where large quantities of sulphur are taken in with water and feed have compromised immune function due to lower copper and thiamine status and hence are at risk of increased susceptibility to infections.

Estudo da atividade antimicrobiana de extrato de folha de Aristolochia gigantea Mart e Zucc / Study of the antimycrobial activity of extracts from the leaves of Aristolochia gigantea Mart and Zucc

Foram investigadas as atividades antibacteriana e antifúngica dos extratos éter de petróleo e alcaloídico de folhas de Aristolochia gigantea Mart e Zucc, pelo método de difusäo em agar. O extrato éter de petróleo mostrou atividade contra uma bactéria Gram-positiva. O extrato alcaloídico apresentou atividade contra duas bactérias Gram-positivas. Uma Gram-negativa, näo apresentando qualquer atividade antifúngica.

Plasma zinc levels throughout pregnancy: a study in Jamaican women, with relevant aspects of nutrition

In a prospective study plasma zinc levels were determined by atomic absorption spectrophotometry in 135 Jamaican women over a two year period. A total of 1237 such determinations were made at fixed intervals throughout pregnancy. Each patient was investigated at 15, 20, 25, 30, 35 and 38 weeks gestation, in labour, and once in the early and in the late puerperium. Zinc being an essential trace element with a wide physiological role in many aspects of metabolism, supplementary studies on the relationship between zinc, folic acid, vitamin A, dietary intake in general, taste acuity and weight gain in pregnancy were undertaken. Results show that plasma zinc levels are lowered during pregnancy, moreso during the second trimester. The levels rise significantly during labour and then fall rapidly towards normal during the puerperium. Daily dietary zinc intake was of the order of 8-10 mg/day (the RDA for pregnancy being 15 mg/day) while protein intake averaged 67 g/day (the RDA being 80-90 g/day). Average weight gain in pregnancy was 12 kg. Plasma vitamin A and red cell folate levels were within normal range in all patients, indicating that there was no state of zinc deficiency interfering with the absorption of these vitamins. Clinical observations and laboratory investigations revealed no signs of any dietary deficiency among the patients. Viewed together, all the facets of this study suggest that the pattern of fall of plasma zinc in pregnancy is a normal physiological change not related to socio-economic status, parity or age. It is concluded that the lowered plasma zinc observed in pregnancy does not reflect a state of true zinc deficiency nor even a state of inadequate dietary zinc intake; it is most likely due to the heavy demand for zinc in the developing fetal tissues and by the expanding maternal blood volume (AU)