NKG2C+CD57+ natural killer with senescent features cells are induced in cutaneous leishmaniasis and accumulate in patients with lesional healing impairment.

Natural killer (NK) cells include different subsets with diverse effector capacities that are poorly understood in the context of parasitic diseases. Here, we investigated inhibitory and activating receptor expression on NK cells in patients with cutaneous leishmaniasis (CL) and explored their phenotypic and functional heterogeneity based on CD57 and NKG2C expression. The expression of CD57 identified NK cells that accumulated in CL patients and exhibited features of senescence. The CD57+ cells exhibited heightened levels of the activating receptor NKG2C and diminished expression of the inhibitory receptor NKG2A. RNA sequencing analyses based on NKG2C transcriptome have revealed two distinct profiles among CL patients associated with cytotoxic and functional genes. The CD57+NKG2C+ subset accumulated in the blood of patients and presented conspicuous features of senescence, including the expression of markers such as p16, yH2ax, and p38, as well as reduced proliferative capacity. In addition, they positively correlated with the number of days until lesion resolution. This study provides a broad understanding of the NK cell biology during Leishmania infection and reinforces the role of senescent cells in the adverse clinical outcomes of cutaneous leishmaniasis.

Salicylic Acid and Water Stress: Effects on Morphophysiology and Essential Oil Profile of Eryngium foetidum.

The exogenous application of bioregulators, such as salicylic acid (SA), has exhibited promising outcomes in alleviating drought stress. Nevertheless, its impact on culantro (Eryngium foetidum L.) remains unexplored. Thus, the aim of this study was to assess how SA impacts the growth, morphophysiology, and essential oil composition of culantro when subjected to drought. To achieve this, culantro plants were grown under three different watering regimes: well-watered, drought-stressed, and re-watered. Additionally, they were either treated with SA (100 µM) or left untreated, with water serving as the control. SA application did not mitigate the effects of drought in biomass production but increased biomass, leaf number, leaf area, and photosynthetic pigments under well-irrigated and re-watered conditions. After a drought period followed by re-watering, plants recovered membrane integrity independently of SA application. Water stress and the exogenous application of SA also modulated the profile of essential oils. This is the first report about SA and drought affecting growth and essential oil composition in culantro.

Outcomes of ventricular tachycardia ablation in patients with ischemic and non-ischemic cardiomyopathy: A propensity-score matched analysis.

INTRODUCTION AND OBJECTIVES: Catheter ablation (CA) is effective in the treatment of ventricular tachycardia (VT). Although some observational data suggest patients with non-ischemic cardiomyopathy (NICM) have less favorable outcomes when compared to those with an ischemic etiology (ICM), direct comparisons are rarely reported. We aimed to compare the outcomes of VT ablation in a propensity-score matched population of ICM or NICM patients. METHODS: Single-center retrospective study of consecutive patients undergoing VT ablation from 2012 to 2023. A propensity score (PS) was used to match ICM and NICM patients in a 1:1 fashion according to age, sex, left ventricular ejection fraction (LVEF), NYHA class, electrical storm (ES) at presentation, and previous endocardial ablation. The outcomes of interest were VT-free survival and all-cause mortality. RESULTS: The PS yielded two groups of 71 patients each (mean age 63±10 years, 92% male, mean LVEF 35±10%, 36% with ES at presentation, and 23% with previous ablation), well matched for baseline characteristics. During a median follow-up of 2.3 (interquartile range IQR 1.3-3.8) years, patients with NICM had a significantly lower VT-free survival (53.5% vs. 69.0%, log-rank p=0.037), although there were no differences regarding all-cause mortality (22.5% vs. 16.9%, log-rank p=0.245). Multivariate analysis identified NICM (HR 2.34 [95% CI 1.32-4.14], p=0.004), NYHA class III/IV (HR 2.11 [95% CI 1.11-4.04], p=0.024), and chronic kidney disease (HR 2.23 [95% CI 1.25-3.96], p=0.006), as independent predictors of VT recurrence. CONCLUSION: Non-ischemic cardiomyopathy patients were at increased risk of VT recurrence after ablation, although long-term mortality did not differ.

Attainment of LDL-Cholesterol Goals in Patients with Previous Myocardial Infarction: A Real-World Cross-Sectional Analysis. / Atingimento das Metas de Colesterol LDL em Pacientes com Histórico de Infarto Agudo do Miocárdio: Estudo Transversal do Mundo Real.

BACKGROUND: The European Society of Cardiology guidelines recommend an LDL-cholesterol (LDL-C) < 55 mg/dL for patients with established cardiovascular disease. While the Friedewald equation to estimate LDL-C is still widely used, the newer Martin-Hopkins equation has shown greater accuracy. OBJECTIVES: We aimed to assess: A) the proportion of patients reaching LDL-C goal and the therapies used in a tertiary center; B) the impact of using the Martin-Hopkins method instead of Friedewald's on the proportion of controlled patients. METHODS: A single-center cross-sectional study including consecutive post-myocardial infarction patients followed by 20 cardiologists in a tertiary hospital. Data was collected retrospectively from clinical appointments that took place after April 2022. For each patient, the LDL-C levels and attainment of goals were estimated from an ambulatory lipid profile using both Friedewald and Martin-Hopkins equations. A two-tailed p-value of < 0.05 was considered statistically significant for all tests. RESULTS: Overall, 400 patients were included (aged 67 ± 13 years, 77% male). Using Friedewald's equation, the median LDL-C under therapy was 64 (50-81) mg/dL, and 31% had LDL-C within goals. High-intensity statins were used in 64% of patients, 37% were on ezetimibe, and 0.5% were under PCSK9 inhibitors. Combination therapy of high-intensity statin + ezetimibe was used in 102 patients (26%). Applying the Martin-Hopkins method would reclassify a total of 31 patients (7.8%). Among those deemed controlled by Friedewald's equation, 27 (21.6%) would have a Martin-Hopkins' LDL-C above goals. CONCLUSIONS: Less than one-third of post-myocardial infarction patients had LDL-C within the goal. Applying the Martin-Hopkins equation would reclassify one-fifth of presumably controlled patients into the non-controlled group.

FUNDAMENTO: As diretrizes da Sociedade Europeia de Cardiologia recomendam um nível de colesterol LDL (LDL-C) < 55 mg/dL para pacientes com doença cardiovascular estabelecida. Embora a fórmula de Friedewald ainda seja amplamente utilizada para estimar o LDL-C, a fórmula mais recente de Martin-Hopkins mostrou maior precisão. OBJETIVOS: Nosso objetivo foi avaliar: A) a proporção de pacientes que atingiram a meta de LDL-C e as terapias utilizadas em um centro terciário; B) o impacto da utilização do método de Martin-Hopkins em vez do método de Friedewald na proporção de pacientes controlados. MÉTODOS: Estudo transversal monocêntrico, incluindo pacientes consecutivos pós-infarto do miocárdio, acompanhados por 20 cardiologistas, em um hospital terciário. Os dados foram coletados retrospectivamente de consultas clínicas realizadas após abril de 2022. Para cada paciente, os níveis de LDL-C e o atingimento das metas foram estimados a partir de um perfil lipídico ambulatorial, utilizando as fórmulas de Friedewald e Martin-Hopkins. Um valor-p bicaudal < 0,05 foi considerado estatisticamente significativo para todos os testes. RESULTADOS: Foram incluídos 400 pacientes (com 67 ± 13 anos, 77% do sexo masculino). Utilizando a fórmula de Friedewald, a mediana de LDL-C sob terapia foi de 64 (50-81) mg/dL, e 31% tinham LDL-C dentro da meta. Estatinas de alta intensidade foram usadas em 64% dos pacientes, 37% estavam em uso de ezetimiba e 0,5% estavam em uso de inibidores de PCSK9. A terapia combinada de estatina de alta intensidade + ezetimiba foi utilizada em 102 pacientes (26%). A aplicação do método de Martin-Hopkins reclassificaria um total de 31 pacientes (7,8%). Entre aqueles considerados controlados pela fórmula de Friedewald, 27 (21,6%) teriam LDL-C estimado por Martin-Hopkins acima da meta. CONCLUSÕES: Menos de um terço dos pacientes pós-infarto do miocárdio apresentaram LDL-C dentro da meta. A aplicação da fórmula de Martin-Hopkins reclassificaria um quinto dos pacientes presumivelmente controlados no grupo de pacientes não controlados.

Natural history of three late-diagnosed classic Galactosemia patients.

The authors report the natural history of three patients with late-diagnosed Classic Galactosemia (CG) (at 16, 19 and 28 years). This was due to a combination of factors: absence of neonatal screening, absence of some typical acute neonatal symptoms, and negative galactosemia screening. This report underlines the value of neonatal screening and the importance of further diagnostic testing in case of late-onset manifestations.

Assessment of myocardial strain patterns in patients with left bundle branch block using cardiac magnetic resonance.

Recently, a classification with four types of septal longitudinal strain patterns was described using echocardiography, suggesting a pathophysiological continuum of left bundle branch block (LBBB)-induced left ventricle (LV) remodeling. The aim of this study was to assess the feasibility of classifying these strain patterns using cardiovascular magnetic resonance (CMR), and to evaluate their association with LV remodeling and myocardial scar. Single center registry included LBBB patients with septal flash (SF) referred to CMR to assess the cause of LV systolic dysfunction. Semi-automated feature-tracking cardiac resonance (FT-CMR) was used to quantify myocardial strain and detect the four strain patterns. A total of 115 patients were studied (age 66 ± 11 years, 57% men, 28% with ischemic heart disease). In longitudinal strain analysis, 23 patients (20%) were classified in stage LBBB-1, 37 (32.1%) in LBBB-2, 25 (21.7%) in LBBB-3, and 30 (26%) in LBBB-4. Patients at higher stages had more prominent septal flash, higher LV volumes, lower LV ejection fraction, and lower absolute strain values (p < 0.05 for all). Late gadolinium enhancement (LGE) was found in 55% of the patients (n = 63). No differences were found between the strain patterns regarding the presence, distribution or location of LGE. Among patients with LBBB, there was a good association between strain patterns assessed by FT-CMR analysis and the degree of LV remodeling and LV dysfunction. This association seems to be independent from the presence and distribution of LGE.

Vitamin D3 inhibits p38 MAPK and senescence-associated inflammatory mediator secretion by senescent fibroblasts that impacts immune responses during ageing.

Vitamin D3 replacement in older insufficient adults significantly improves their antigen-specific varicella zoster virus (VZV) cutaneous immunity. However, the mechanisms involved in this enhancement of cutaneous immunity are not known. Here, we show for the first time that vitamin D3 blocks the senescence-associated secretory phenotype (SASP) production by senescent fibroblasts by partially inhibiting the p38 MAPK pathway. Furthermore, transcriptomic analysis of skin biopsies from older subjects after vitamin D3 supplementation shows that vitamin D3 inhibits the same inflammatory pathways in response to saline as the specific p38 inhibitor, losmapimod, which also enhances immunity in the skin of older subjects. Vitamin D3 supplementation therefore may enhance immunity during ageing in part by blocking p38 MAPK signalling and in turn inhibit SASP production from senescent cells in vivo.

Obesogenic polystyrene microplastic exposures disrupt the gut-liver-adipose axis.

Microplastics (MP) derived from the weathering of polymers, or synthesized in this size range, have become widespread environmental contaminants and have found their way into water supplies and the food chain. Despite this awareness, little is known about the health consequences of MP ingestion. We have previously shown that the consumption of polystyrene (PS) beads was associated with intestinal dysbiosis and diabetes and obesity in mice. To further evaluate the systemic metabolic effects of PS on the gut-liver-adipose tissue axis, we supplied C57BL/6J mice with normal water or that containing 2 sizes of PS beads (0.5 and 5 µm) at a concentration of 1 µg/ml. After 13 weeks, we evaluated indices of metabolism and liver function. As observed previously, mice drinking the PS-containing water had a potentiated weight gain and adipose expansion. Here we found that this was associated with an increased abundance of adipose F4/80+ macrophages. These exposures did not cause nonalcoholic fatty liver disease but were associated with decreased liver:body weight ratios and an enrichment in hepatic farnesoid X receptor and liver X receptor signaling. PS also increased hepatic cholesterol and altered both hepatic and cecal bile acids. Mice consuming PS beads and treated with the berry anthocyanin, delphinidin, demonstrated an attenuated weight gain compared with those mice receiving a control intervention and also exhibited a downregulation of cyclic adenosine monophosphate (cAMP) and peroxisome proliferator-activated receptor (PPAR) signaling pathways. This study highlights the obesogenic role of PS in perturbing the gut-liver-adipose axis and altering nuclear receptor signaling and intermediary metabolism. Dietary interventions may limit the adverse metabolic effects of PS consumption.

The Mediating Role of Self-Esteem in the Relationship Between Perceived Ethnic Discrimination and Continuance Commitment of Migrant Workers.

This study aims to examine the relationship between perceived ethnic discrimination by migrant workers (applicants for international protection) and continuance commitment, and to analyze whether this relationship is mediated by self-esteem. In addition, it aims to contribute to the literature on the organizational outcomes of perceived ethnic discrimination. This research was conducted through a questionnaire survey of 411 migrants who applied for international protection in Turkey. As a result of the study, perceived ethnic discrimination was found to be a predictor of continuance commitment and self-esteem. In addition, it was observed that self-esteem has a mediating role in the relationship between perceived ethnic discrimination and continuance commitment. The results offer important implications for organizations and organization managers on how migrant workers should be managed and which issues require specific attention. The application of the study on migrant workers and the examination of these variables provide important contributions and practical implications to the literature. In addition, this is a rare study that examines the mediator model with the variables specified in the model using social identity theory, which has not yet been widely covered in existing literature.

Atingimento das Metas de Colesterol LDL em Pacientes com Histórico de Infarto Agudo do Miocárdio: Estudo Transversal do Mundo Real / Attainment of LDL-Cholesterol Goals in Patients with Previous Myocardial Infarction: A Real-World Cross-Sectional Analysis

Resumo Fundamento: As diretrizes da Sociedade Europeia de Cardiologia recomendam um nível de colesterol LDL (LDL-C) < 55 mg/dL para pacientes com doença cardiovascular estabelecida. Embora a fórmula de Friedewald ainda seja amplamente utilizada para estimar o LDL-C, a fórmula mais recente de Martin-Hopkins mostrou maior precisão. Objetivos: Nosso objetivo foi avaliar: A) a proporção de pacientes que atingiram a meta de LDL-C e as terapias utilizadas em um centro terciário; B) o impacto da utilização do método de Martin-Hopkins em vez do método de Friedewald na proporção de pacientes controlados. Métodos: Estudo transversal monocêntrico, incluindo pacientes consecutivos pós-infarto do miocárdio, acompanhados por 20 cardiologistas, em um hospital terciário. Os dados foram coletados retrospectivamente de consultas clínicas realizadas após abril de 2022. Para cada paciente, os níveis de LDL-C e o atingimento das metas foram estimados a partir de um perfil lipídico ambulatorial, utilizando as fórmulas de Friedewald e Martin-Hopkins. Um valor-p bicaudal < 0,05 foi considerado estatisticamente significativo para todos os testes. Resultados: Foram incluídos 400 pacientes (com 67 ± 13 anos, 77% do sexo masculino). Utilizando a fórmula de Friedewald, a mediana de LDL-C sob terapia foi de 64 (50-81) mg/dL, e 31% tinham LDL-C dentro da meta. Estatinas de alta intensidade foram usadas em 64% dos pacientes, 37% estavam em uso de ezetimiba e 0,5% estavam em uso de inibidores de PCSK9. A terapia combinada de estatina de alta intensidade + ezetimiba foi utilizada em 102 pacientes (26%). A aplicação do método de Martin-Hopkins reclassificaria um total de 31 pacientes (7,8%). Entre aqueles considerados controlados pela fórmula de Friedewald, 27 (21,6%) teriam LDL-C estimado por Martin-Hopkins acima da meta. Conclusões: Menos de um terço dos pacientes pós-infarto do miocárdio apresentaram LDL-C dentro da meta. A aplicação da fórmula de Martin-Hopkins reclassificaria um quinto dos pacientes presumivelmente controlados no grupo de pacientes não controlados.

Abstract Background: The European Society of Cardiology guidelines recommend an LDL-cholesterol (LDL-C) < 55 mg/dL for patients with established cardiovascular disease. While the Friedewald equation to estimate LDL-C is still widely used, the newer Martin-Hopkins equation has shown greater accuracy. Objectives: We aimed to assess: A) the proportion of patients reaching LDL-C goal and the therapies used in a tertiary center; B) the impact of using the Martin-Hopkins method instead of Friedewald's on the proportion of controlled patients. Methods: A single-center cross-sectional study including consecutive post-myocardial infarction patients followed by 20 cardiologists in a tertiary hospital. Data was collected retrospectively from clinical appointments that took place after April 2022. For each patient, the LDL-C levels and attainment of goals were estimated from an ambulatory lipid profile using both Friedewald and Martin-Hopkins equations. A two-tailed p-value of < 0.05 was considered statistically significant for all tests. Results: Overall, 400 patients were included (aged 67 ± 13 years, 77% male). Using Friedewald's equation, the median LDL-C under therapy was 64 (50-81) mg/dL, and 31% had LDL-C within goals. High-intensity statins were used in 64% of patients, 37% were on ezetimibe, and 0.5% were under PCSK9 inhibitors. Combination therapy of high-intensity statin + ezetimibe was used in 102 patients (26%). Applying the Martin-Hopkins method would reclassify a total of 31 patients (7.8%). Among those deemed controlled by Friedewald's equation, 27 (21.6%) would have a Martin-Hopkins' LDL-C above goals. Conclusions: Less than one-third of post-myocardial infarction patients had LDL-C within the goal. Applying the Martin-Hopkins equation would reclassify one-fifth of presumably controlled patients into the non-controlled group.

Intranasal delivery of LaAg vaccine improves immunity of aged mice against visceral Leishmaniasis.

There are no approved vaccines yet for human visceral leishmaniasis (VL), the most severe form of the leishmaniasis clinical manifestations that is fatal in over 95 % of untreated cases. It is well-accepted that immunological changes during aging have deleterious impact on the efficacy of vaccines and response to infections. In this work, we compared the response of young and aged mice to intranasal vaccination with killed Leishmania amazonensis promastigote antigens (LaAg) that were then challenged with L. infantum infection, a species that causes visceral leishmaniasis. Intranasal vaccination with LaAg induced a similar reduction in parasitism and hepatosplenomegaly in both young and aged mice compared to their unvaccinated counterparts. Following infection, there was also a less prominent inflammatory profile particularly in the vaccinated aged group, with lower production of TNF-α and nitrite compared to the respective unvaccinated group. Interestingly, the LaAg intranasal vaccination promoted increased production of IFN-γ that was observed in both young- and aged vaccinated groups. Additionally, CD4+ and CD8+T cells from both vaccinated groups presented decreased expression of the inhibitory receptors PD-1 and KLRG1 compared to their unvaccinated controls. Interestingly, a strong positive correlation was observed between the expression of both inhibitory receptors PD-1 and KLRG1 and parasitism, which was more conspicuous in the unvaccinated-aged mice than in the others. Overall, this study helps define new strategies to improve vaccine effectiveness and provides a perspective for prophylactic alternatives against leishmaniasis.

Association Between the Magnitude of Glycemic Control and Body Weight Loss With GLP-1 Receptor Agonists and Risk of Atherosclerotic Cardiovascular Disease: A Systematic Review and Meta-analyses of Randomized Diabetes Cardiovascular Outcomes Trials.

PURPOSE: Reduction of major atherosclerotic cardiovascular events (MACE) has not been consistent among different glucagon-like peptide-1 receptor agonists (GLP-1 RAs) in patients with type 2 diabetes mellitus (T2DM). The aim of this study was to assess the association between the magnitude of glycemic control, body weight loss, and reductions in systolic blood pressure (SBP) and low-density lipoprotein cholesterol (LDL-C) achieved through GLP-1 RA therapy and MACE. METHODS: Electronic databases (MEDLINE, CENTRAL, SCOPUS) were searched through March 2023. Studies were eligible if they were cardiovascular outcome trials (CVOTs) comparing GLP-1 RAs versus placebo in T2DM patients. The outcome of interest was 3-point MACE - cardiovascular death, myocardial infarction, or stroke. Random-effects meta-regression analyses evaluated the associations between reductions of HbA1c, body weight, SBP and LDL-C and reduction of MACE. RESULTS: Overall, 8 CVOTs were included (60079 patients, 30693 with GLP-1 RAs). Reductions of HbA1C were associated with the reduction of 3P-MACE (Log RR -0.290 [95% CI -0.515;-0.064], p = 0.012), with an estimated RR reduction of 25% for each 1% absolute reduction in HbA1C levels. Body weight loss was associated with the reduction of 3P-MACE (Log RR -0.068 [95% CI -0.135;-0.001], p = 0.047), with an estimated RR reduction of 7% for each 1 kg reduction in body weight. Reductions of SBP (Log RR -0.058 [95% CI -0.192;0.076], p = 0.396) and LDL-C (Log RR -0.602 [95% CI -4.157;2.953], p = 0.740) were not associated with the reduction of 3P-MACE. CONCLUSIONS: In T2DM patients, more potent GLP-1 RAs in reducing HbA1c and body weight were associated with greater reductions of MACE.

The management and clinical outcomes of pregnancies in women with urea cycle disorders: A review of the literature and results of an international survey.

An increasing number of women with urea cycle disorders (UCDs) are reaching child-bearing age and becoming pregnant. Improved diagnostics and increased awareness of inherited metabolic diseases has also led to more previously undetected women being diagnosed with a UCD during or shortly after pregnancy. Pregnancy increases the risk of acute metabolic decompensation with hyperammonemia-which can occur in any trimester, and/or the postpartum period, and may lead to encephalopathy, psychosis, coma, and even death, if not diagnosed promptly and treated appropriately. There are also (theoretical) concerns that a maternal UCD, or its treatment, may cause potential risks for the unborn child. Currently evidence on management and outcome of pregnancies in UCDs is limited to case reports and there are no clear guidelines. In order to inform management and investigate outcomes of pregnancies in women with a UCD, we performed a retrospective review of published cases and analyzed data collected from an international online survey. We conclude that, although risk during the intra- and postpartum period exists, multidisciplinary management by an experienced team and a prospective plan usually result in successful pregnancy, labor, delivery, and postpartum period. No deaths were reported in mothers managed accordingly. With the exception of male neonates with Ornithine Transcarbamylase deficiency, the clinical outcome of children born to mothers with UCDs appears positive, although follow-up is limited. The outcome for women presenting with a first acute metabolic decompensation during pregnancy or postpartum is less favorable. Deaths were associated with diagnostic delay/late management of hyperammonemia in previously undiagnosed women.

Follow-up of Patients with Hereditary Metabolic Diseases during the 3 Years of the Pandemic in the Reference Center for Hereditary Metabolism Diseases of the Centro Hospitalar Universitário Lisboa Norte.

INTRODUCTION: The adult unit of the Reference Center for Hereditary Metabolism Diseases of the Centro Hospitalar Universitário Lisboa Norte was created in 2002. The team that supports this unit is made up of several specialists, including 2 Internal Medicine Doctors and 2 Nutritionists. The unit carries out its activity mainly in an outpatient clinic on Fridays. Between March 2020 and December 2022, the team adapted the support given to this unit, transforming some external appointments into non-face-to-face appointments in order to maintain contact with patients and reduce the deslocation to the CHULN. METHODS: The analysis reported below reflects the activity in face-to-face and non-face-to-face appointment of the medical team and nutrition team in the critical period. RESULTS/CASE REPORT: A total of 220 patients were evaluated, 56.4% female and 43.6% male. Regarding the evaluated pathologies, these were divided into 3 groups: aminoacidopathies - 40%, organic aciduria - 6.5% and other metabolic diseases - 53.5%. During these three years a total of 580 nutrition appointments were scheduled, 457 face-to-face and 123 non-face-to-face. 32% of patients scheduled did not attend the appointments or it was not possible to make telephone contact. This percentage is divided into 90% face-to-face appointments and 10% nonface- to-face appointments. Regarding medical appointments, the total was 797, 667 of which were face-to-face and 130 non-face-to-face. 16.8% of absences were registered in face-to-face and non-face-to-face appointments. 98.5% of absences concern non-face-to-face appointments. CONCLUSION: Despite the troubled period worldwide, support for these patients was always ensured, both by the Medical team and the Nutrition team. Despite the solutions found to keep patients safe, in this specific period, the % of absences from the outpatient clinic is quite high, and one of the main justifications presented by the patients is related to the fact that they are afraid to go to the hospital. With regard to absences recorded in non-face-to-face appointments, there were several situations in which patients reported not being able to answer the phone during their working hours.

Crosslinked chitosan microparticles as a safe and efficient DNA carrier for intranasal vaccination against cutaneous leishmaniasis.

Intranasal (i.n.) vaccination with adjuvant-free plasmid DNA encoding the leishmanial antigen LACK (LACK DNA) has shown to induce protective immunity against both cutaneous and visceral leishmaniasis in rodents. In the present work, we sought to evaluate the safety and effectiveness of d,l-glyceraldehyde cross-linked chitosan microparticles (CCM) as a LACK DNA non-intumescent mucoadhesive delivery system. CCM with 5 µm of diameter was prepared and adsorbed with a maximum of 2.4 % (w/w) of DNA with no volume alteration. Histological analysis of mouse nostrils instilled with LACK DNA / CCM showed microparticles to be not only mucoadherent but also mucopenetrant, inducing no local inflammation. Systemic safeness was confirmed by the observation that two nasal instillations one week apart did not alter the numbers of bronchoalveolar cells or blood eosinophils; did not alter ALT, AST and creatinine serum levels; and did not induce cutaneous hypersensitivity. When challenged in the footpad with Leishmania amazonensis, mice developed significantly lower parasite loads as compared with animals given naked LACK DNA or CCM alone. That was accompanied by increased stimulation of Th1-biased responses, as seen by the higher T-bet / GATA-3 ratio and IFN-γ levels. Together, these results demonstrate that CCM is a safe and effective mucopenetrating carrier that can increase the efficacy of i.n. LACK DNA vaccination against cutaneous leishmaniasis.

In vitro effect of alpha-bisabolol and its synthetic derivatives on macrophages, promastigotes, and amastigotes of Leishmania amazonensis and Leishmania infantum.

Cutaneous and visceral leishmaniasis are public health problems in Africa, Asia, Europe, and America. The treatment has a high cost and toxicity. Thus, this work aims to evaluate the leishmanicidal activity of alpha-bisabolol and its three synthetic derivatives, P1, P2, and P3, on the promastigotes and amastigotes Leishmania infantum and L. amazonensis forms. Alpha-bisabolol showed the lowest IC50 with 3.43 for L. amazonensis promastigotes, while P1 was the most toxic for L. infantum with an IC50 of 9.10. The derivative P3 was better for the amastigote form, with an IC50 of 3.39 for L. amazonensis. All the compounds effectively decreased the intracellular load of amastigote and its ability to turn promastigote again. Thus, alpha-bisabolol and its three synthetic derivatives were effective in their leishmanicidal activity. Therefore, it can be an option for developing new treatments against leishmaniasis.