Intestine alkaline phosphatase (iALP), which is secreted by enterocytes plays an important role in maintaining gut homeostasis and protection. Furthermore, iALP was reported to act as an anti-inflammatory factor by inhibiting both Toll like receptor 4 (Tlr4) and Myeloid differentiation primary response gene 88 (Myd88) dependent inflammatory cascades. Spirulina pectin is a heteropolysaccharide derived from marine Spirulina maxima. Since recent studies have proved nanoparticles are more efficient in delivery of therapeutic agents, we produced nano-particle form of modified Spirulina pectin and investigated its effect in iALP modulation in mouse model.
Modified spirulina pectin nanoparticles (MSmPNPs) were prepared by modification of Spirulina pectin (SmP) by high temperature and pressure exposures followed by a sonication. In this study, to evaluate MSmPNPs activity on intestine alkaline phosphatase, C57BL/6 mice were used. Mice were administrated MSmPNPs (a dose of 1.62 ± 0.01g/kg per day) orally with drinking water for four weeks. Control group was maintained with parallel to test group and after four weeks, mice duodenums were isolated. Part of the duodenum was used for western-blot analysis to determine the relative protein expression level of iALP and it was quantified. Furthermore, qRT-PCR was performed for Alkaline phosphatase 3 (Akp3) and alkaline phosphatase intestinal (Alpi) for iALP related gene expression. Tlr4 and Myd88 gene expressions were tested to confirm the anti-inflammatory action by induced iALP.
Western blot data showed significant relative iALP protein expression (1.92-fold) in MSmPNPs treated mice compare to control group. Gene expression of Akp3 had significant (p<0.05) 5.21-fold upregulation and Alpi expression had 1.25-fold upregulation. Meanwhile Tlr4 and Myd88 gene expressions had significant (p<0.05) 0.11-fold and 0.43-fold downregulation, respectively. Overall results suggest that MSmPNPs could induce the intestine alkaline phosphatase expression both at transcriptional and translational levels, while repressing the expression of inflammatory Tlr4 and Myd88 cascade and promote anti-inflammatory activity in the mouse gut.