Appswe

The 3xTg-AD mice harboring three mutant alleles (APP_Swe, PS1_M146V, and Tau_P301L) were purchased from Jackson Laboratory and kept in animals room of Shenzhen Center for Disease Control and Prevention (SZCDC). All animals were maintained specific conditions (temperature: 22 ± 2° C, relative humidity: 55 ± 15%) with free access to feed and water. In our experiment, the 7-month-old female mice were divided into three groups, and each group contained 10 to 15 mice. The 3xTg-AD mice were administrated daily with loganin (20 mg/kg body weight) for duration of 6 weeks. To avoid possible deviation to mice from long-term intraperitoneal injection, the control mice were injected with saline solution. Animal’s body weight was monitored every 3 days. After loganin treatment, mice were given to behavioral tests and then sacrificed for biochemical analysis. All animal care and experimental procedures were approved by the Ethics Committee of SZCDC. Every effort was made to alleviate animal’s suffering and minimize the number of mice used.

Aβ_1–42, Aβ_1–42NT, Aβ_1–42DM, Aβ_1–42I, Aβ_1–42Cl, and Aβ_1–42NF (>95%, lyophilized powder) are synthesized by China Peptides (Shanghai, China). Thioflavin T (ThT), 4,4′-dianilino-1,1′-binaphthyl-5,5′-disulfonic acid (Bis-ANS) are obtained from Sigma–Aldrich (St. Louis, MO, USA). All other reagents are in the analytical grade. The female triple transgenic model mice of AD carrying human gene mutants APPswe, PS1M146V, and tauP301L are purchased from the Jackson Laboratory (Bar Harbor, ME, USA).

Experiments were conducted using transgenic mice (3xTg) harboring the following three transgenes: presenilin PS1M146V knock-in mutation (PS1^M146V), human transgenes and the APP Swedish mutation (APPSwe), and microtubule-associated protein tau (tauP30IL) (The Jackson Laboratory, Sacramento, CA, USA). As these mice age, they gradually exhibit synaptic dysfunction neuropathy; Aβ protein accumulates in the later stage, and plaques and neurofibrillary tangles are formed. At the age of 3–6 months, Aβ deposits are detected in some regions of the brain. At the age of 12 months, the pathological features include highly phosphorylated tau protein and neurofibrillary tangles in the hippocampus. In this study, only female mice were used.

All animal care and experimental procedures were performed according to the guidelines and were approved by the Animal Care and Use Committee of Guizhou Medical University. Mice (maximum of 6 mice per cage) were caged in a climate-controlled room (23 ± 0.5 °C) with 12 h of light and darkness with an ad libitum supply of food and water. Female C57BL/6 mice (12 weeks old) were procured from the Aniphe BioLab. Additionally, female APP/PS1 transgenic mice (8 weeks old), expressing human presenilin 1 (A246E) and Swedish mutant APP (APP_Swe) were sourced from Jackson laboratory (Catalog#41848-JAX; B6C3-Tg (APP695)3DboTg (PSEN1)5Dbo/Mmjax). To ensure the welfare of the mice during certain procedures and prior to euthanasia, they were anesthetized using 4% isoflurane (Catalog#R510-22-10, Rayward Life Technology), bilateral thoracotomy and transcardial perfusion with physiological saline-containing heparin (10 U/mL) were then performed. Once these procedures were complete, the mouse brains were extracted. These specimens were then either reserved for biochemical analysis or were subjected to immunohistochemistry (IHC) staining. To ascertain the validity of the transgenic specimens, genotyping was meticulously carried out for each mouse, thus confirming the specific transgenic lineage.

In this study two animal models of AD were used. Seven and 12 mo 3xTg male mice, harboring three mutations associated with familial AD (APP_Swe, MAPT_P301L, and PS1_M146V) on a congenic C57BL/6J background, and control littermates were purchased by The Jackson Laboratory (Stock number 008880) (10 (link), 24 (link)). 5XFAD mice, which co-overexpress a triple-mutant human APP (Swedish mutation: K670N, M671L; Florida mutation: I716V; London mutation: V717I) and a double-mutant human PS1 (M146L and L286V mutations), and B6SJL mice were purchased from Jackson Laboratories and bred at Centro Stabulario Interdipartimentale, Unimore. Experimental 3 and 5 mo 5XFAD mice were obtained by crossing hemizygous 5XFAD mice with B6SJL breeders. All mice were kept in conditioned rooms with stable temperature (21°C) and humidity (60%), on a light/dark cycle of 12 hours (h). Food and water were available ad libitum and body weight was recorded throughout the entire observation period. All animal procedures were approved by the Committee on Animal Health and Care of the University of Modena and Reggio Emilia and Italian Ministry of Health (protocol number: n°974/2016-PR) and conducted in accordance with National Institutes of Health guidelines.