918 resultados para reverse-phase high-performance liquid chromatography


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An active, solvent-free solid sampler was developed for the collection of 1,6-hexamethylene diisocyanate (HDI) aerosol and prepolymers. The sampler was made of a filter impregnated with 1-(2-methoxyphenyl)piperazine contained in a filter holder. Interferences with HDI were observed when a set of cellulose acetate filters and a polystyrene filter holder were used; a glass fiber filter and polypropylene filter cassette gave better results. The applicability of the sampling and analytical procedure was validated with a test chamber, constructed for the dynamic generation of HDI aerosol and prepolymers in commercial two-component spray paints (Desmodur(R) N75) used in car refinishing. The particle size distribution, temporal stability, and spatial uniformity of the simulated aerosol were established in order to test the sample. The monitoring of aerosol concentrations was conducted with the solid sampler paired to the reference impinger technique (impinger flasks contained 10 mL of 0.5 mg/mL 1-(2-methoxyphenyl)piperazine in toluene) under a controlled atmosphere in the test chamber. Analyses of derivatized HDI and prepolymers were carried out by using high-performance liquid chromatography and ultraviolet detection. The correlation between the solvent-free and the impinger techniques appeared fairly good (Y = 0.979X - 0.161; R = 0.978), when the tests were conducted in the range of 0.1 to 10 times the threshold limit value (TLV) for HDI monomer and up to 60-mu-g/m3 (3 U.K. TLVs) for total -N = C = O groups.

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A two-step high-performance liquid chromatography method is described, using a CN column and an alpha 1-acid glycoprotein column, which allows the measurement of the enantiomers of the hydroxy metabolites of trimipramine in plasma of trimipramine-treated patients. Of the four patients analyzed, three showed approximately equimolar concentrations of the (D)- and (L)-enantiomers of the hydroxy metabolites (2-hydroxy-trimipramine and 2-hydroxy desmethyltrimipramine), and one was found to have roughly twice as much of the (L)-form and of the (D)-form of 2-hydroxy trimipramine and 2-hydroxy desmethyltrimipramine. From the data available on the pharmacological effects of the enantiomers of trimipramine, it is postulated that this interindividual variability in its pharmacokinetics is another factor that could contribute to the interindividual variability in its pharmacodynamics.

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The new angiotensin-converting enzyme (ACE) inhibitor idrapril acts by binding the catalytically important zinc ion to a hydroxamic group. We investigated its pharmacodynamic and pharmacokinetic properties in 8 healthy men: Increasing doses of 1, 5, and 25 mg idrapril as well as placebo or 5 mg captopril were administered intravenously (i.v.) at 1-week intervals. Six of the subjects received 100 mg idrapril orally (p.o.) last, and two ingested oral placebo as a double-blind control. Blood pressure (BP) and heart rate (HR) remained unchanged. No serious side effects were observed. ACE inhibition in vivo was evaluated by changes in the ratio of specifically measured plasma angiotensin II (AngII) and AngI concentrations determined by high-performance liquid chromatography/radioimmunoassay (HPLC/RIA) techniques. Plasma ACE activity in vitro was estimated by radioenzymatic assay; it was suppressed by > or = 93% at 15 min after injection of 25 mg idrapril or 5 mg captopril and by 96% 2 h after idrapril intake. Mean AngII levels were decreased dose dependently at 15 min after idrapril injections. At the same time, plasma renin activity (PRA) and AngI increased according to the doses. The AngII/AngI ratio was clearly related to plasma idrapril levels (r = -0.88, n = 60). Oral idrapril inhibited ACE maximally at 1-4 h after dosing, when < 7% of initial ACE activity was observed in vitro and in vivo. Idrapril is a safe and efficient ACE inhibitor in human subjects. It is well absorbed orally. Besides having a slightly slower onset of action, idrapril has pharmacodynamic effects comparable to those of captopril.

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BACKGROUND:HIV-1-infected patients vary considerably by their response to antiretroviral treatment, drug concentrations in plasma, toxic events, and rate of immune recovery. This variability could have a genetic basis. We did a pharmacogenetics study to analyse the association between response to antiretroviral treatment and allelic variants of several genes. METHODS:In 123 patients, we did PCR analyses of the gene for the multidrug-resistance transporter (MDR1), which codes for P-glycoprotein, of genes coding for isoenzymes of cytochrome P450, CYP3A4, CYP3A5, CYP2D6, and CYP2C19, and of the gene for the chemokine receptor CCR5. We measured concentrations in plasma of the antiretroviral agents efavirenz and nelfinavir by high-performance liquid-chromatography, and measured levels of P-glycoprotein expression, CD4-cell count, and HIV-1 viraemia. FINDINGS: Median drug concentrations in patients with the MDR1 3435 TT, CT, and CC genotypes were at the 30th, 50th, and 75th percentiles, respectively (p=0.0001). In patients with CYP2D6 extensive-metaboliser or poor-metaboliser alleles, median drug concentrations were at percentiles 45 and 62.5, respectively (p=0.04). Patients with the MDR1 TT genotype 6 months after starting treatment had a greater rise in CD4-cell count (257 cells/microL) than patients with the CT (165 cells/microL) and CC (121 cells/microL) genotype (p=0.0048), and the best recovery of naïve CD4-cells. INTERPRETATION:The polymorphism MDR1 3435 C/T predicts immune recovery after initiation of antiretroviral treatment. This finding suggests that P-glycoprotein has an important role in admittance of antiretroviral drugs to restricted compartments in vivo.

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OBJECTIVE: To genetically and phenotypically describe a new ADAM9 homozygous mutation in a consanguineous family from Egypt with autosomal recessive cone-rod dystrophy (arCRD), anterior polar and posterior subcapsular cataract. DESIGN, SETTING AND PARTICIPANTS: The parents and their six children were included. They underwent a complete ophthalmic examination with fundus photography and optical coherence tomography (OCT). INTERVENTION: DNA was extracted from peripheral blood from all family members. Screening for mutations in genes known to be implicated in retinal disorders was done with the IROme, an in-solution enrichment array, followed by high-throughput sequencing. Validation of the results was done by bidirectional Sanger sequencing of ADAM9 exon 14, including exon-intron junctions. Screening of normal controls was done by denaturing high-performance liquid chromatography. RESULTS: arCRD was diagnosed in the mother and two of her children. Bilateral anterior polar and posterior subcapsular cataract was observed in the mother and bilateral dot cataract was diagnosed in three of the four children not affected with arCRD, one of whom also had glaucoma. The characteristics of the arCRD were childhood-onset visual impairment, reorganisation of the retinal pigment epithelium with mid-periphery greyish-white discolouration, attenuated retinal vasculatur and optic disc pallor. A coloboma-like macular lesion was observed in one of the arCRD-affected children. IROme analysis identified a c.1396-2A>G homozygous mutation in the splice acceptor site of intron 13 of ADAM9. This mutation was homozygous in the two children affected by arCRD and in their affected mother. This mutation was heterozygous in the unaffected father and the four unaffected children. CONCLUSIONS AND RELEVANCE: We identified a novel autosomal recessive ADAM9 mutation causing arCRD in a consanguineous Egyptian family. The percentage of arCRD cases caused by mutation in ADAM9 remains to be determined. Few families are reported in the literature to date; hence extensive clinical descriptions of families with ADAM9 mutations are of significant importance.

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The enzyme triosephosphate isomerase (TPI, EC 5.3.1.1) was purified from extracts of epimastigote forms of Trypanosoma cruzi. The purification steps included: hydrophobic interaction chromatography on phenyl-Sepharose, CM-Sepharose, and high performance liquid gel filtration chromatography. The CM-Sepharose material contained two bands (27 and 25 kDa) with similar isoelectric points (pI 9.3-9.5) which could be separated by gel filtration in high performance liquid chromatography. Polyclonal antibodies raised against the porcine TPI detected one single polypeptide on western blot with a molecular weight (27 kDa) identical to that purified from T. cruzi. These antibodies also recognized only one band of identical molecular weight in western blots of several other trypanosomatids (Blastocrithidia culicis, Crithidia desouzai, Phytomonas serpens, Herpertomonas samuelpessoai). The presence of only one enzymatic form of TPI in T. cruzi epimastigotes was confirmed by agarose gel activity assay and its localization was established by immunocytochemical analysis. The T. cruzi purified TPI (as well as other trypanosomatid' TPIs) is a dimeric protein, composed of two identical subunits with an approximate mw of 27,000 and it is resolved on two dimensional gel electrophoresis with a pI of 9.3. Sequence analysis of the N-terminal portion of the 27 kDa protein revealed a high homology to Leishmania mexicana and T. brucei proteins

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Using high performance liquid chromatography (HPLC) analysis it was possible to determine simultaneously the concentration of organic acids (pyruvate, lactate, succinate, fumarate, malate, acetate, propionate, acetoacetate, and ß-hydroxybutyrate) in the digestive gland and the extracellular concentration of these same acids in the hemolymph of estivating Biomphalaria glabrata, the intermediate host of Schistosoma mansoni. After a 7 day period of estivation, there was a significant increase in the tissue levels of lactate, succinate, malate and acetate compared to non-estivating snails. After 14 days of estivation, the levels of lactate and acetate were also significantly elevated. The hemolymph concentrations of pyruvate and acetate increased significantly after 7 days and acetate concentrations continued to be significantly increased up to 14 days of estivation. The other organic acids studied, such as ketone body acetoacetate and ß-hydroxybutyrate or the volatile acid propionate, did not accumulate. Their tissue concentrations, however, increased on the 7th day of estivation and reached normal levels within two weeks of estivation for some of them. One should take into consideration how the reduction in metabolism can be handled under aerobic conditions, and what role anaerobic pathways may play in both energy formation and redox balance processes.

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BACKGROUND: Advances in nebulizer design have produced both ultrasonic nebulizers and devices based on a vibrating mesh (vibrating mesh nebulizers), which are expected to enhance the efficiency of aerosol drug therapy. The aim of this study was to compare 4 different nebulizers, of 3 different types, in an in vitro model using albuterol delivery and physical characteristics as benchmarks. METHODS: The following nebulizers were tested: Sidestream Disposable jet nebulizer, Multisonic Infra Control ultrasonic nebulizer, and the Aerogen Pro and Aerogen Solo vibrating mesh nebulizers. Aerosol duration, temperature, and drug solution osmolality were measured during nebulization. Albuterol delivery was measured by a high-performance liquid chromatography system with fluorometric detection. The droplet size distribution was analyzed with a laser granulometer. RESULTS: The ultrasonic nebulizer was the fastest device based on the duration of nebulization; the jet nebulizer was the slowest. Solution temperature decreased during nebulization when the jet nebulizer and vibrating mesh nebulizers were used, but it increased with the ultrasonic nebulizer. Osmolality was stable during nebulization with the vibrating mesh nebulizers, but increased with the jet nebulizer and ultrasonic nebulizer, indicating solvent evaporation. Albuterol delivery was 1.6 and 2.3 times higher with the ultrasonic nebulizer and vibrating mesh nebulizers devices, respectively, than with the jet nebulizer. Particle size was significantly higher with the ultrasonic nebulizer. CONCLUSIONS: The in vitro model was effective for comparing nebulizer types, demonstrating important differences between nebulizer types. The new devices, both the ultrasonic nebulizers and vibrating mesh nebulizers, delivered more aerosolized drug than traditional jet nebulizers.

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OBJECTIVES: Comparison of doxorubicin uptake, leakage and spatial regional blood flow, and drug distribution was made for antegrade, retrograde, combined antegrade and retrograde isolated lung perfusion, and pulmonary artery infusion by endovascular inflow occlusion (blood flow occlusion), as opposed to intravenous administration in a porcine model. METHODS: White pigs underwent single-pass lung perfusion with doxorubicin (320 mug/mL), labeled 99mTc-microspheres, and Indian ink. Visual assessment of the ink distribution and perfusion scintigraphy of the perfused lung was performed. 99mTc activity and doxorubicin levels were measured by gamma counting and high-performance liquid chromatography on 15 tissue samples from each perfused lung at predetermined localizations. RESULTS: Overall doxorubicin uptake in the perfused lung was significantly higher (P = .001) and the plasma concentration was significantly lower (P < .0001) after all isolated lung perfusion techniques, compared with intravenous administration, without differences between them. Pulmonary artery infusion (blood flow occlusion) showed an equally high doxorubicin uptake in the perfused lung but a higher systemic leakage than surgical isolated lung perfusion (P < .0001). The geometric coefficients of variation of the doxorubicin lung tissue levels were 175%, 279%, 226%, and 151% for antegrade, retrograde, combined antegrade and retrograde isolated lung perfusion, and pulmonary artery infusion by endovascular inflow occlusion (blood flow occlusion), respectively, compared with 51% for intravenous administration (P = .09). 99mTc activity measurements of the samples paralleled the doxorubicin level measurements, indicating a trend to a more heterogeneous spatial regional blood flow and drug distribution after isolated lung perfusion and blood flow occlusion compared with intravenous administration. CONCLUSIONS: Cytostatic lung perfusion results in a high overall doxorubicin uptake, which is, however, heterogeneously distributed within the perfused lung.

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Introduction. Fibromyalgia is a chronic pain syndrome with unknown etiology. Recent studies have shown some evidence demonstrating that oxidative stress may have a role in the pathophysiology of fibromyalgia. However, it is still not clear whether oxidative stress is the cause or the effect of the abnormalities documented in fibromyalgia. Furthermore, the role of mitochondria in the redox imbalance reported in fibromyalgia also is controversial. We undertook this study to investigate the role of mitochondrial dysfunction, oxidative stress, and mitophagy in fibromyalgia. Methods. We studied 20 patients (2 male, 18 female patients) from the database of the Sevillian Fibromyalgia Association and 10 healthy controls. We evaluated mitochondrial function in blood mononuclear cells from fibromyalgia patients measuring, coenzyme Q10 levels with high-performance liquid chromatography (HPLC), and mitochondrial membrane potential with flow cytometry. Oxidative stress was determined by measuring mitochondrial superoxide production with MitoSOX™ and lipid peroxidation in blood mononuclear cells and plasma from fibromyalgia patients. Autophagy activation was evaluated by quantifying the fluorescence intensity of LysoTracker™ Red staining of blood mononuclear cells. Mitophagy was confirmed by measuring citrate synthase activity and electron microscopy examination of blood mononuclear cells. Results. We found reduced levels of coenzyme Q10, decreased mitochondrial membrane potential, increased levels of mitochondrial superoxide in blood mononuclear cells, and increased levels of lipid peroxidation in both blood mononuclear cells and plasma from fibromyalgia patients. Mitochondrial dysfunction was also associated with increased expression of autophagic genes and the elimination of dysfunctional mitochondria with mitophagy. Conclusions. These findings may support the role of oxidative stress and mitophagy in the pathophysiology of fibromyalgia.

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Pregnancy reduces maternal risk of breast cancer in the long term, but the biological determinants of the protection are unknown. Animal experiments suggest that estrogens and progesterone could be involved, but direct human evidence is scant. A case-control study (536 cases and 1,049 controls) was nested within the Finnish Maternity Cohort. Eligible were primiparous women who delivered at term a singleton offspring before age 40. For each case, two individually matched controls by age (±6 months) and date of sampling (±3 months) were selected. Estradiol, estrone and progesterone in first-trimester serum were measured by high-performance liquid chromatography tandem mass spectrometry and sex-hormone binding globulin (SHBG) by immunoassay. Odds ratios (OR) and 95% confidence intervals (CI) were estimated through conditional logistic regression. In the whole study population there was no association of breast cancer with any of the studied hormones. In analyses stratified by age at diagnosis, however, estradiol concentrations were positively associated with risk of breast cancer before age 40 (upper quartile OR, 1.81; CI, 1.08-3.06), but inversely associated with risk in women who were diagnosed ≥age 40 (upper quartile OR, 0.64; CI, 0.40-1.04), p(interaction) 0.004. Risk estimates for estrone mirrored those for estradiol but were less pronounced. Progesterone was not associated with risk of subsequent breast cancer. Our results provide initial evidence that concentrations of estrogens during the early parts of a primiparous pregnancy are associated with maternal risk of breast cancer and suggest that the effect may differ for tumors diagnosed before and after age 40.

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AIMS: To characterize and compare the pharmacokinetic profiles of bromazepam, omeprazole and paracetamol when administered by the oral and nasogastric routes to the same healthy cohort of volunteers. METHODS: In a prospective, monocentric, randomized crossover study, eight healthy volunteers received the three drugs by the oral (OR) and nasogastric routes (NT). Sequential plasma samples were analyzed by high-performance liquid chromatography-UV, pharmacokinetic parameters (Cmax, AUC(0-infinity), t(1/2), k(e), tmax) were compared statistically, and Cmax, AUC(0-infinity) and t(max) were analyzed for bioequivalence. RESULTS: A statistically significant difference was seen in the AUC(0-infinity) of bromazepam, with nasogastric administration decreasing availability by about 25%: AUC(OR) = 2501 ng mL(-1) h; AUC(NT) = 1855 ng mL(-1) h (p < 0.05); ratio (geometric mean) = 0.74 [90% confidence interval (CI) 0.64-0.87]. However, this does not appear to be clinically relevant given the usual dosage range and the drug's half-life (approx. 30 h). A large interindividual variability in omeprazole parameters prevented any statistical conclusion from being drawn in terms of both modes of administration despite their similar average profile: AUC(OR) = 579 ng mL(-1) h; AUC(NT) = 587 ng mL(-1) h (p > 0.05); ratio (geometric mean) = 1.01 (90% CI 0.64-1.61). An extended study with a larger number of subjects may possibly provide clearer answers. The narrow 90% confidence limits of paracetamol indicate bioequivalence: AUC(OR) = 37 microg mL(-1) h; AUC(NT) = 41 microg mL(-1) h(p > 0.05); ratio (geometric mean) = 1.12 (90% CI 0.98-1.28). CONCLUSION: The results of this study show that the nasogastric route of administration does not appear to cause marked, clinically unsuitable alterations in the bioavailability of the tested drugs.

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SUMMARY Pulmonary Pulmonary disease is the primary cause of morbidity and mortality in cystic fibrosis patients (CF). Airways of CF patients are early colonized by various bacteriae, and an intense inflammatory response participates to airways destruction. Accumulation of neutrophils releasing proteolytic enzymes and free radicals induce progressive lung tissue destruction in CF. Among several inflammatory mediators implicated in this process, chemotactic factors such as leukotriene B4 (LTB4), product of arachidonic omega-6 polyunsaturated fatty acid (PUFA), plays an important role. Many anti-inflammatory therapies including corticosteroids, ibuprofen, macrolides, antioxidants and antiproteinases have been proposed in CF over the last 20 years. In complement to these various approaches, dietary supplementation with polyunsaturated fatty acids (PUFA) omega-3, known to favor the synthesis of less inflammatory leukotriene B5 (LTB5), could also represent a potential. therapy. The objective of this thesis was to assess the impact of this nutritional approach on several CF neutrophil functions. In addition, we have also examined the influence of this approach on various clinical parameters, to assess the feasibility of future studies specifically oriented towards clinical effects. To that endeavour, a high performance liquid chromatography method has been developed and validated, allowing the simultaneous determination of LTB4 and LTB5 produced by stimulated human polymorphonuclear leukocytes. This method was applied for the analysis of samples collected from CF patients taking part to a double-blind, randomized, crossover placebo-controlled clinical trial aiming at evaluating in these patients the immunomodulatary effect of a liquid supplementation enriched in omega-3 PUFA in CF. This study has shown that omega-3 PUFA are incorporated in CF neutrophil membranes and results into a modulation of leucotrienes B production, as testified by a three fold decrease in LTB4/LTB5 ratio after omega-3 PUFA supplementation. However, no clinical improvement was observed upon omega-3 supplementation, very reproducible results observed allow to be optimistic for a future larger trial focused on clinical outcomes. In conclusion, even if the results show that omega-3 PUFA are absorbed by CF patients and that the subsequent decrease in LTB4/LTB5 ratio suggests that in such conditions, neutrophils may produce less pro-inflammatory mediators, the clinical relevance of those observations remains to be demonstrated. Future multicentric studies focusing on clinical endpoints are still warranted to determine the importance of omega-3 PUFA in CF therapeutics. RÉSUMÉ Les patients atteints de mucoviscidose (patients CF) souffrent d'infections pulmonaires récurrentes. Celles-ci provoquent un afflux permanent de neutrophiles dans le poumon, neutrophiles qui libèrent des enzymes protéolytiques et des radicaux libres responsables à long terme de la destruction du tissu pulmonaire et, finalement, de l'insuffisance respiratoire, première cause de morbidité et de mortalité chez ces patients. La réponse inflammatoire ainsi induite peut être réduite par divers traitements anti-inflammatoires, tels que corticoïdes, anti-inflammatoires non stéroïdiens ou azithromycine. L'apport oral en acides gras polyinsaturés (AGPI) oméga-3 pourrait être une autre approche thérapeutique intéressante. Ces nutriments sont décrits comme possédant des propriétés anti-inflammatoires notamment en favorisant la synthèse d'eicosanoïdes pourvus d'une activité inflammatoire moindre par rapport à ceux issus d'une autre famille d'AGPI, les oméga-6. Ce travail de thèse a pour objectif premier d'évaluer l'impact de cette approche nutritionnelle sur diverses fonctions du neutrophile chez des patients CF. Cependant un intérêt de nature prospective a également été porté à certains paramètres cliniques, afin d'évaluer la faisabilité d'une future étude axée sur des effets cliniques. Pour ce faire, une méthode de chromatographie liquide à haute performance couplée à un spectromètre de masse a été développée et validée. Cette analyse devait permettre le dosage simultané de deux eicosanoïdes, le leucotriène B4 (LTB4) issu des AGPI oméga-6 et le leucotriène B5 (LTB5) issu des AGPI oméga-3. Puis, une étude clinique, double aveugle, randomisée, croisée sans période de washout, mais contrôlée avec un placebo, a été mise au point pour évaluer l'effet immunomodulateur de ces AGPI oméga-3 donnés sous la forme d'un liquide nutritif chez des patients CF. Les résultats de cette étude ont permis de démontrer l'absorption intestinale des AGPI oméga-3 par les patients. De plus, leur administration a permis de modifier la production de teucotriène B. En effet, le ratio LTB4/LTB5 a été diminué de près de trois fois sous liquide nutritif enrichi en AGPI oméga-3. Enfin aucune différence n'a pu être notée pour les paramètres cliniques; toutefois les résultats reproductibles observés permettent d'envisager qu'une future étude multicentrique axée sur des effets cliniques est faisable. En conclusion, la modification de la composition en AGPI membranaires du neutrophile observée durant cette étude laisse penser que ces nutriments sont absorbés par les patients CF. La modulation de la production en LTBs qui en découle permet d'envisager un potentiel effet anti-inflammatoire. Toutefois, la relevance clinique de ces observations restent à être démontrée. A l'heure actuelle, une étude multicentrique, focalisée sur des paramètres cliniques, est nécessaire avant de pouvoir se prononcer sur l'utilisation des AGPI oméga-3 chez les patients CF.

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We evaluated the in vitro anti-Mycobacterium tuberculosis activity and the cytotoxicity of dichloromethane extract and pure compounds from the leaves of Calophyllum brasiliense. Purification of the dichloromethane extract yielded the pure compounds (-) mammea A/BB (1), (-) mammea B/BB (2) and amentoflavone (3). The compound structures were elucidated on the basis of spectroscopic and spectrometric data. The contents of bioactive compounds in the extracts were quantified using high performance liquid chromatography coupled to an ultraviolet detector. The anti-M. tuberculosis activity of the extracts and the pure compounds was evaluated using a resazurin microtitre assay plate. The cytotoxicity assay was performed in J774G.8 macrophages using the 3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyl tetrazolium bromide colourimetric method. The quantification of the dichloromethane extract showed (1) and (2) at concentrations of 31.86 ± 2.6 and 8.24 ± 1.1 µg/mg of extract, respectively. The dichloromethane and aqueous extracts showed anti-M. tuberculosis H37Rv activity of 62.5 and 125 µg/mL, respectively. Coumarins (1) and (2) showed minimal inhibitory concentration ranges of 31.2 and 62.5 µg/mL against M. tuberculosis H37Rv and clinical isolates. Compound (3) showed no activity against M. tuberculosis H37Rv. The selectivity index ranged from 0.59-1.06. We report the activity of the extracts and coumarins from the leaves of C. brasiliense against M. tuberculosis.

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The polar hydroethanolic extract from Selaginella sellowii(SSPHE) has been previously proven active on intracellular amastigotes (in vitro test) and now was tested on hamsters infected with Leishmania (Leishmania) amazonensis (in vivo test). SSPHE suppressed a 100% of the parasite load in the infection site and draining lymph nodes at an intralesional dose of 50 mg/kg/day × 5, which was similar to the results observed in hamsters treated with N-methylglucamine antimonate (Sb) (28 mg/Kg/day × 5). When orally administered, SSPHE (50 mg/kg/day × 20) suppressed 99.2% of the parasite load in infected footpads, while Sb suppressed 98.5%. SSPHE also enhanced the release of nitric oxide through the intralesional route in comparison to Sb. The chemical fingerprint of SSPHE by high-performance liquid chromatography with diode-array detection and tandem mass spectrometry showed the presence of biflavonoids and high molecular weight phenylpropanoid glycosides. These compounds may have a synergistic action in vivo. Histopathological study revealed that the intralesional treatment with SSPHE induced an intense inflammatory infiltrate, composed mainly of mononuclear cells. The present findings reinforce the potential of this natural product as a source of future drug candidates for American cutaneous leishmaniasis.