Proteomic profiling of the brain of mice with experimental cerebral malaria

An update on cerebral malaria for therapeutic intervention

BACKGROUND

Cerebral malaria is often pronounced as a major life-threatening neurological complication of Plasmodium falciparum infection. The complex pathogenic landscape of the parasite and the associated neurological complications are still not elucidated properly. The growing concerns of drugresistant parasite strains along with the failure of anti-malarial drugs to subdue post-recovery neuro-cognitive dysfunctions in cerebral malaria patients have called for a demand to explore novel biomarkers and therapeutic avenues. Due course of the brain infection journey of the parasite, events such as sequestration of infected RBCs, cytoadherence, inflammation, endothelial activation, and blood-brain barrier disruption are considered critical.

METHODS

In this review, we briefly summarize the diverse pathogenesis of the brain-invading parasite associated with loss of the blood-brain barrier integrity. In addition, we also discuss proteomics, transcriptomics, and bioinformatics strategies to identify an array of new biomarkers and drug candidates.

CONCLUSION

A proper understanding of the parasite biology and mechanism of barrier disruption coupled with emerging state-of-art therapeutic approaches could be helpful to tackle cerebral malaria.

Synergistic Effect of Combined Artesunate and Tetramethylpyrazine in Experimental Cerebral Malaria

Intravenous artesunate is effective against cerebral malaria (CM), but high mortality and neurological sequelae in survivors are inevitable. We investigated the effect of combined artesunate and tetramethylpyrazine using mouse models of experimental cerebral malaria (ECM). Artesunate + tetramethylpyrazine reduced microvascular blockage and improved neurological function, including the rapid murine coma and behavior scale (RMCBS), leading to improved survival and reduced pathology in ECM. This combination downregulated the expression of adhesion molecules and sequestration of parasitized red blood cells (pRBCs), increased cerebral blood flow, nerve growth factor (b-NGF), vascular endothelial growth factor A (VEGF-A), and neurotrophin (brain-derived neurotrophic factor (BDNF), neurotrophic factor-3 (NT-3)) levels, and alleviated hippocampal neuronal damage and astrocyte activation. Down- (n = 128) and upregulated (n = 64) proteins were identified in the artesunate group, while up- (n = 217) and downregulated (n = 177) proteins were identified in the artesunate + tetramethylpyrazine group, presenting a significantly altered proteome profile. KEGG analysis showed that 166 differentially expressed proteins were enriched in the Art group and 234, in the artesunate + tetramethylpyrazine group. The neuroprotective effects of artesunate + tetramethylpyrazine were mainly related to proteins involved in axon development and transportation between blood and brain. These results suggested that artesunate + tetramethylpyrazine could be a potential adjuvant therapy against CM, but this will have to be confirmed in future studies and trials.

Quantitative proteomic study of the plasma reveals acute phase response and LXR/RXR and FXR/RXR activation in the chronic unpredictable mild stress mouse model of depression

Major depressive disorder is a severe neuropsychiatric disease that negatively impacts the quality of life of a large portion of the population. However, the molecular mechanisms underlying depression are still unclear. The pathogenesis of depression involves several brain regions. However, most previous studies have focused only on one specific brain region. Plasma and brain tissues exchange numerous components through the blood-brain barrier. Therefore, in the present study, plasma samples from control (CON) mice and mice subjected to chronic unpredictable mild stress (CUMS) were used to investigate the molecular pathogenesis of depression, and the association between the peripheral circulation and the central nervous system. A total of 47 significant differentially expressed proteins were identified between the CUMS and CON group by an isobaric tag for relative and absolute quantitation (iTRAQ) coupled with tandem mass spectrometry approach. These 47 differentially expressed proteins were analyzed with ingenuity pathway analysis (IPA) software. This revealed that the acute phase response, LXR/RXR and FXR/RXR activation, the complement system and the intrinsic prothrombin activation pathway were significantly changed. Four of the significant differentially expressed proteins (lipopolysaccharide binding protein, fibrinogen β chain, α-1 antitrypsin, and complement factor H) were validated by western blotting. the present findings provide a novel insight into the molecular pathogenesis of depression.