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Targeting circulating labile heme as a defense strategy against malaria.

ABSTRACT: Severe presentations of malaria emerge as Plasmodium (P.) spp. parasites invade and lyse red blood cells (RBC), producing extracellular hemoglobin (HB), from which labile heme is released. Here, we tested whether scavenging of extracellular HB and/or labile heme, by haptoglobin (HP) and/or hemopexin (HPX), respectively, counter the pathogenesis of severe presentations of malaria. We found that circulating labile heme is an independent risk factor for cerebral and non-cerebral presentations of severe P. falciparum malaria in children. Labile heme was negatively correlated with circulating HP and HPX, which were, however, not risk factors for severe P. falciparum malaria. Genetic Hp and/or Hpx deletion in mice led to labile heme accumulation in plasma and kidneys, upon Plasmodium infection This was associated with higher incidence of mortality and acute kidney injury (AKI) in ageing but not adult Plasmodium-infected mice, and was corroborated by an inverse correlation between heme and HPX with serological markers of AKI in P. falciparum malaria. In conclusion, HP and HPX act in an age-dependent manner to prevent the pathogenesis of severe presentation of malaria in mice and presumably in humans.

SUBMITTER: Ramos S

PROVIDER: S-EPMC10837040 | biostudies-literature | 2024 Apr

REPOSITORIES: biostudies-literature

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Targeting circulating labile heme as a defense strategy against malaria.

Ramos Susana S Jeney Viktoria V Figueiredo Ana A Paixão Tiago T Sambo Maria Rosário MR Quinhentos Vatúsia V Martins Rui R Gouveia Zélia Z Carlos Ana Rita AR Ferreira Ana A Pais Teresa F TF Lainé Hugo H Faísca Pedro P Rebelo Sofia S Cardoso Silvia S Tolosano Emanuela E Penha-Gonçalves Carlos C Soares Miguel P MP

Life science alliance 20240202 4

Severe presentations of malaria emerge as <i>Plasmodium (P.) spp.</i> parasites invade and lyse red blood cells (RBC), producing extracellular hemoglobin (HB), from which labile heme is released. Here, we tested whether scavenging of extracellular HB and/or labile heme, by haptoglobin (HP) and/or hemopexin (HPX), respectively, counter the pathogenesis of severe presentations of malaria. We found that circulating labile heme is an independent risk factor for cerebral and non-cerebral presentation ...[more]

PMID: 38307624

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Targeting circulating labile heme as a defense strategy against malaria.

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Targeting circulating labile heme as a defense strategy against malaria.

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