In vivo antischistosomal activity profiling and efficacy of niosomal Spirulina platensis and praziquantel combined remedy against murine Schistosoma mansoni infection

Schistosomiasis is a serious parasite disease with a high rate of mortality and negative financial impacts in subtropical and tropical locations like Egypt. The goal of this study was to investigate the anti-schistosomal effect of Spirulina platensis (SP) and Spirulina loaded niosomes (SPN), either in the presence or absence of praziquantel (PZQ) against S. mansoni in experimentally infected mice. Six groups have been involved in the study, five groups were infected with S. mansoni cercariae and subjected independently to different treatments of SP, SPN, and PZQ or the preceding two combinations, in addition to one untreated group which acts as a control. At the 8th week, mice were euthanized, and besides a histopathological assessment of the liver granuloma, the number of worms, tissue egg load, and oogram pattern were estimated. To evaluate the condition of the liver oxidative stress, the levels of malondialdehyde and reduced glutathione in liver homogenates were investigated. Additionally, to assess the anti-inflammatory properties, serum cytokines (IFN-γ, TNF-α, IL-13, and IL-10) and CD4⁺ immunohistochemistry expression were determined. The results demonstrated that each of the investigated parameters was significantly changed by both SPN and/or SPN with PZQ treatments alongside PZQ. The highest therapeutic effect was obtained in SPN combined with a half dose of PZQ which achieved 100 % reduction in both the total worm burden and the highest reduction in the intestinal (93.22 %) and hepatic (94.4 %) egg content, as well, moreover 40.5 % reduction of the granuloma size. Furthermore, serum cytokine levels {(TNF-α (11 ± 0.5 (P ˂ 0.001)), (IFN-γ (19.7 ± 1.2 (P ˂ 0.001)) and (IL-13 (53.65 ± 1.4 (P ˂ 0.001))}, as well as CD4⁺ cells (6.5 ± 0.65 (P ˂ 0.001)) were reduced. While, IL-10 (61.1 ± 2.1 (P ˂ 0.001)) was increased due to the same treatment additional to its antioxidant properties by reduced lipid peroxidation (LPO) (1.1975 ± 0.05(P ˂ 0.001)) but increased reduced glutathione (GSH) (2.31± 0.15 (P˂0.001)). In conclusion, SPN has a schistosomicidal, antioxidant, and hepatoprotective role. SPN has a strong synergistic effect when combined with PZQ which showed anti-inflammatory action. Hence, SPN + PZQ offers promising alternatives for future schistosomiasis therapeutic research.