Parasite immune response against schistosomal antigens involves both the innate and adaptive immune response. Tregs have a suppressive effect and play a role on the parasite's immune evasion. This study aimed to evaluate active compounds of Allium sativum (AS) ethanol extract and the impact of AS extract alone or in combination with praziquantel on Tregs and anti-inflammatory cytokines TGF- β and IL-10 in mice infected with S. mansoni . Phytochemical screening of AS bulbs for various active constituents and qualitative and quantitative analysis of the flavonoids and phenolic acids were done using HPLC. Measurement of splenocytes Treg cell phenotypes and anti-inflammatory cytokines TGF- β and IL-10 was done by flow cytometric analysis. The data are expressed as mean ± SD. Statistical significance was determined by one-way ANOVA utilizing the statistical package (SPSS version 17.0). HPLC of AS ethanol extract revealed presence of 22 and 18 compounds of flavonoids and phenolic acids, respectively. S. mansoni infection upregulated the Treg cells subsets (CD4, CD25, Foxp3) frequencies and the levels of TGF- β and IL-10 anti-inflammatory cytokines when compared to healthy control. AS ethanol extract alone or combined with PZQ decreases the production of Treg cells from spleen in addition to the reduction in anti- inflammatory cytokines IL-10 and TGF- β. This study recommends that the combination of AS ethanol extract and PZQ may play a role in maintaining the homeostasis of the immune system during schistosomiasis by decreasing Tr eg cells and anti-inflammatory cytokines IL- 10 and TGF- β production.
Cryptosporidiosis is a serious illness in immunodeficient patients, and there is still no drug that can completely remove the parasite from the host. The present study represents the first report investigating the impact of the active molecule chlorogenic acid (CGA), naturally isolated from Moringa oleifera leaf extract (EMOLE), on immunosuppressed, Cryptosporidium parvum-infected BALB/c mice. Mice were divided into five groups: normal mice, infected immunosuppressed mice, and infected immunosuppressed mice treated with EMOLE, CGA, and nitazoxanide (NTZ) drugs. Parasitological, immunological, and histopathological investigations were recorded besides differences in the mice' body weight. Infected control mice showed elevated levels of oocyst shedding throughout the study. The EMOLE- and CGA-treated groups showed 84.2% and 91.0% reductions in oocyst shedding, respectively, with no significant difference compared to the drug control. The inflammatory markers IFN-γ, IL-6, IL-1β, and TNF-α were significantly higher in the infected control group. Treatment with 300 mg/kg/day of EMOLE or 30 mg/kg/day of CGA significantly downregulated pro-inflammatory cytokine levels compared to the infected group, although they did not change significantly compared to the NTZ-treated group. Histopathology of intestinal sections showed inflammatory and pathological changes in the infected control group. Low-grade tissue changes and an obvious improvement in villi structure were seen in mice treated with CGA. This study highlighted the role of CGA, isolated and purified from EMOLE, as an effective anti-inflammatory agent in eradicating C. parvum infection.