Leishmanial apolipoprotein A-I expression: a possible strategy used by the parasite to evade the host's immune response

Immuno-Informatics Insight into the Relationship Between Cholesterol and Cytokines in Cutaneous Leishmaniasis: From clinics to computation

Objectives

The role of serum cholesterol and its interactions with cytokines in human cutaneous leishmaniasis (CL) pathophysiology is unknown. This study aimed to evaluate the correlation among serum total cholesterol (TC), very-low-density lipoprotein cholesterol (VLDL-C), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), triglycerides (TG) and cytokines (including interleukin [IL] 10), IL-12 and tumour necrosis factor-alpha [TNF-α]) in CL. The cholesterol-cytokine network was analysed to illuminate the pathogenesis of CL.

Methods

This case-control study was conducted from December 2022 to March 2023 in hospitals within Baghdad and Wasit provinces, Iraq, and included CL and CL-free subjects ranging between 20-30 years of age. The serum samples were analysed via commercial kits to detect TC, IL-10, IL-12, TNF-α, VLDL-C, LDL-C, HDL-C and TG levels. Computational efforts to dissect cholesterol-protein interaction networks were employed using STITCH.

Results

A total of 50 CL and 25 control subjects were included. The TC, HDL-C and LDL-C levels in CL patients were markedly lower (P = 0.0001) than in control subjects, whereas the IL-10, IL-12, TNF-α, VLDL-C and TG levels were higher in CL patients. Serum cholesterol showed no correlation with cytokines; however, a significant correlation (r = 0.57; P = 0.026) was observed between IL-12 and TNF-α. Within the cholesterol-protein network, cholesterol potentially interacted with IL-10, connecting cholesterol to modules with immunological significance, including TRAF1, TRAF2 and TNF receptor superfamily member 1B, as well as IL-10, IL-10RA and IL-12RB1.

Conclusion

This study showed the alteration of lipid and lipoprotein in CL and introduced 2 immunological modules in CL, highlighting the importance of the altered cholesterol-cytokine interaction network in CL.

Selenium and protozoan parasitic infections: selenocompounds and selenoproteins potential

The current drug treatments against protozoan parasitic diseases including Chagas, malaria, leishmaniasis, and toxoplasmosis represent good examples of drug resistance mechanisms and have shown diverse side effects. Therefore, the identification of novel therapeutic strategies and drug compounds against such life-threatening diseases is urgent. According to the successful usage of selenium (Se) compounds-based therapy against some diseases, this therapeutic strategy has been recently further underlined against these parasitic diseases by targeting different parasite´s essential pathways. On the other hand, due to the important functions played by parasite selenoproteins in their biology (such as modulating the host immune response), they can be also considered as a novel therapeutic strategy by designing specific inhibitors against these important proteins. In addition, the immunomodulatory potentiality of these compounds to trigger T helper type 1 (Th1) cells and cytokine-mediated immune response for the substantial induction of proinflammatory cytokines, thus, Se, selenoproteins, and parasite selenoproteins could be further investigated to find possible vaccine antigens. Herein, we collect and present the results of some studies regarding Se-based therapy against protozoan parasitic diseases and highlight relevant information and some viewpoints that might be insightful to advance toward more effective studies in the future.

Highlighting the interplay of microRNAs from Leishmania parasites and infected-host cells

Leishmania parasites, the causative agents of leishmaniasis, are protozoan parasites with the ability to modify the signalling pathway and cell responses of their infected host cells. These parasite strategies alter the host cell environment and conditions favouring their replication, survival and pathogenesis. Since microRNAs (miRNAs) are able to post-transcriptionally regulate gene expression processes, these biomolecules can exert critical roles in controlling Leishmania-host cell interplay. Therefore, the identification of relevant miRNAs differentially expressed in Leishmania parasites as well as in infected cells, which affect the host fitness, could be critical to understand the infection biology, pathogenicity and immune response against these parasites. Accordingly, the current review aims to address the differentially expressed miRNAs in both, the parasite and infected host cells and how these biomolecules change cell signalling and host immune responses during infection. A deep understanding of these processes could provide novel guidelines and therapeutic strategies for managing and treating leishmaniasis.