Entamoeba histolytica is a pathogenic, parasitic protozoan that can infect the large intestine and cause amoebiasis, an illness responsible for at least 100,000 deaths annually worldwide. The capacity of human milk to kill amoebas 6,15 and the amoebicidal action of secretory immunoglobulin type A (sIgA) 16 have been reported. However, it is unknown which other components of milk are amoebicides. As milk contains several microbicidal components, we fractionated milk and tested each fraction against trophozoites in axenic cultures to describe any amoebicidal effects of other components of human and bovine milk such as lactoferrin, lysozyme and sIgA. We also sought to identify any combined effect among these molecules. Objectives: To identify amoebicidal components in human milk and the effect of iron on the amoebicidal activity. Original ResearchDesign: Investigation in axenic cultures of Entamoeba histolytica trophozoites.Methods: Amoebas were treated with 5%-20% of human, bovine and swine milk, with 10% of human milk fractions (i.e., casein, proteins except casein and fat) or with 1 mg/ml of human milk apo-lactoferrin, human secretory immunoglobulin type A (sIgA) and chicken egg-white lysozyme (i.e., purified proteins). Milk proteins were detected using immunoblot. Confocal microscopy was used to define the interaction of milk proteins (100 µM each) and amoebas. Experiments were done at least three times in triplicate, and mean and standard deviations were calculated.Results: Human and bovine milk were amoebicidal showing a concentration-dependent effect. The amoebicidal effect was increased in the absence of iron. Milk protein fractions, with the exception of casein, were the components responsible for the amoebicidal activity found. Apo-lactoferrin, sIgA and lysozyme were identified in the amoebicidal milk protein fraction. Apo-lactoferrin showed the major amoebicidal effect. These proteins, either alone or in combination, showed a killing effect on the trophozoites.They bound to the amoebic membrane causing cell rounding, lipid disruption and damage. Conclusions:Milk proteins such as apo-lactoferrin, sIgA and lysozyme are able to kill Entamoeba histolytica trophozoites.This study confirms the importance of feeding breast milk to newborns.

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Chagas disease is one of the most important parasitic diseases in Latin America, affecting 16 to 18 million people. Nifurtimox and Benznidazol are drugs that are commonly used in its treatment; however, these drugs produce several adverse reactions and are not effective in the chronic phase of the disease. Therefore, the design, synthesis, and biological evaluation of new compounds with potential activity against Trypanozoma cruzi are of great importance. We review six proteins involved in the biochemical metabolism of Trypanosoma cruzi that have recently been studied as potential targets for designing new drugs for Chagas disease. These are farnesyl pyrophosphate synthase, trans-sialidase, cruzain cystein protease, trypanothione reductase, glucose 6-phosphate-dehydrogenase, glyceraldehyde 3-phosphate-dehydrogenase, and alpha-hydroxy acid dehydrogenase. We also review the advances of compounds recently designed based on structure-activity, and the perspectives of new compounds that inhibit these therapeutic targets.

Platelets are small, anucleated cell fragments that activate in response to a wide variety of stimuli, triggering a complex series of intracellular pathways leading to a hemostatic thrombus formation at vascular injury sites. However, in essential hypertension, platelet activation contributes to causing myocardial infarction and ischemic stroke. Reported abnormalities in platelet functions, such as platelet hyperactivity and hyperaggregability to several agonists, contribute to the pathogenesis and complications of thrombotic events associated with hypertension. Platelet membrane lipid composition and fluidity are determining for protein site accessibility, structural arrangement of platelet surface, and response to appropriate stimuli. The present study aimed to demonstrate whether structural and biochemical abnormalities in lipid membrane composition and fluidity characteristic of platelets from hypertensive patients influence the expression of the Epithelial Sodium Channel (ENaC), fundamental for sodium influx during collagen activation. Wb, cytometry and quantitative Reverse Transcription-Polymerase Chain Reaction (qRT-PCR) assays demonstrated ENaC overexpression in platelets from hypertensive subjects and in relation to control subjects. Additionally, our results strongly suggest a key role of β-dystroglycan as a scaffold for the organization of ENaC and associated proteins. Understanding of the mechanisms of platelet alterations in hypertension should provide valuable information for the pathophysiology of hypertension.

Stimulation with laser acupuncture at 650 and 980 nm at BL20 in STZ-induced diabetic rats has antihyperglycaemic activity. The results support further evaluation of laser acupuncture as an alternative or complementary treatment for the control of hyperglycaemia.