Modulation of the Response to and Pathogenesis of Leprosy.

The initial infection by the obligate intracellular bacillus evolves to leprosy in a small subset of the infected individuals. Transmission is believed to occur mainly by exposure to bacilli present in aerosols expelled by infected individuals with high bacillary load. -specific DNA has been detected in the blood of asymptomatic household contacts of leprosy patients years before active disease onset, suggesting that, following infection, the bacterium reaches the lymphatic drainage and the blood of at least some individuals.

Heme-induced ROS in Trypanosoma cruzi activates CaMKII-like that triggers epimastigote proliferation. One helpful effect of ROS.

Heme is a ubiquitous molecule that has a number of physiological roles. The toxic effects of this molecule have been demonstrated in various models, based on both its pro-oxidant nature and through a detergent mechanism. It is estimated that about 10 mM of heme is released during blood digestion in the blood-sucking bug's midgut.

The Role of Heme and Reactive Oxygen Species in Proliferation and Survival of Trypanosoma cruzi.

Trypanosoma cruzi, the protozoan responsible for Chagas disease, has a complex life cycle comprehending two distinct hosts and a series of morphological and functional transformations. Hemoglobin degradation inside the insect vector releases high amounts of heme, and this molecule is known to exert a number of physiological functions. Moreover, the absence of its complete biosynthetic pathway in T.

The heme uptake process in Trypanosoma cruzi epimastigotes is inhibited by heme analogues and by inhibitors of ABC transporters.

Heme (iron protoporphyrin IX) is an important molecule involved in many biological reactions, including oxygen transport, respiration, photosynthesis and drug detoxification. Trypanosoma cruzi parasites, the etiological agent of Chagas' disease, take up heme from the environment to supply their nutritional needs because they do not synthesize this cofactor. However, the mechanisms involved in heme transport across biological membranes are poorly understood.