ABSTRACT
Aim To study the modulation effects of HKSX capsule on Alzheimer's disease (AD) and to preliminarily explore its mechanism using SAMP8 as an AD model.Methods SAMP8 mice aged 4 months were randomly divided into model group ( P8 group) , HKSX low-dose group (L-HKSX group) , HKSX high- dose group ( H-HKSX group) , and senescence-accel- erated mouse/resistance 1 (SAMR1 ) at the same age was used as normal control group ( R1 group).New object recognition and Morris water maze experiments were used to detect the learning and memory abilities of each group.Levels of A(3, _40 and A(3, 42 were detected by ELISA, and the expression levels of LC3- U , p62, Beclin-1 , PSD95 and Syn in hippocampus of each group were detected by Western blot.Results Compared with model group, both low and high doses of HKSX could enhance the D1 in new object recognition test, increase number of crossing the platform anrl the time spent in the target quadrant, and shorten the escape latency.Besides, it also enhanced the clearance °f Ap, _40 and AfJ, _42 , up-regulated the relative expression of Beclin-1 and LC3- II and down-regulated the expression of P62.In addition, it increased the expression of synaptic-related proteins PSD95 and Syn.Conclusions HKSX capsule can regulate the expression of autophagy-related proteins and improve autoph- agv dysfunction, which in turn reduce the deposition of A(3 in vivo to alleviate its cytotoxicity and improve synaptic plasticity.Thus, HKSX can improve the learning and memory deficits of AD mice.
ABSTRACT
Systemic delivery of nucleic acids to the central nervous system (CNS) is a major challenge for the development of RNAinterference-based therapeutics due to lack of stability, target specificity, non-permeability to the blood–brain barrier (BBB),and lack of suitable carriers. Using a designed bi-functional fusion protein TARBP-BTP in a complex with siRNA, weearlier demonstrated knockdown of target genes in the brain of both AbPP-PS1 (Alzheimer’s disease, AD) and wild-typeC57BL/6 mice. In this report, we further substantiate the approach through an extended use in AbPP-PS1 mice, which upontreatment with seven doses of b-secretase AbPP cleaving Enzyme 1 (BACE1) TARBP-BTP:siRNA, led to target-specificeffect in the mouse brain. Concomitant gene silencing of BACE1, and consequent reduction in plaque load in the cerebralcortex and hippocampus ([60%) in mice treated with TARBP-BTP:siRNA complex, led to improvement in spatial learningand memory. The study validates the efficiency of TARBP-BTP fusion protein as an efficient mediator of RNAi, givingconsiderable scope for future intervention in neurodegenerative disorders through the use of short nucleic acids as genespecific inhibitors.