GENERAL INFORMATION 
...........................

1. Dataset title:
Dataset_Peripheral_Blood_tau_LVG

2. Authors:
Vegas-Gomez, Laura; Pizarro, Matias; Garcia-Martin, Jesús; Arredondo-Alcala, Maria Angeles; Bustamante, Bianca; Gonzalez-Silva, Carolina; Matus, Soledad; Diaz-Espinoza, Rodrigo; Gutierrez, Antonia; Morales, Rodrigo; Duran-Aniotz, Claudia; Moreno-Gonzalez, Ines.

3. Author contact information: 
Ines Moreno-Gonzalez, PhD
Dept. Cell Biology, Genetics and Physiology
Faculty of Sciences, University of Malaga
Campus Teatinos 29071, Malaga, Spain 
Tel: +34 952132398
Email: inesmoreno@uma.es


METHODOLOGICAL INFORMATION 
.................................


1. Description of the methods for collection/generation of data: 

- Behavioral data collected come from rotarod test, Y-maze test and the Morris water maze (MWM). Behavioral data from rotarod and Y-maze were collected in situ, whereas MWM test data were recorded from videos analysed with Ethovision XT 18 (Noldus).

- Inmunohistochemical data were obtained through imaging-based quantification methods. Histological sections were examined under a Nikon Eclipse 80i microscope, and images were acquired using Nikon ACT-2U software (Nikon Corporation). Image quantification was performed using FIJI (ImageJ, NIH), converting images to 8-bit format and measuring pixel intensity within defined regions of interest (e.g., hippocampus). Loadings were normalized by the area of the selected region. For double immunofluorescence staining, sections were examined using a confocal laser scanning microscope (Leica Stellaris 8).

- Western blot data were quantified using a similar image-based approach. Membranes were visualized using the ChemiDoc™ imaging system (Bio-Rad), connected to a computer running ImageLab 6.1 software. The intensity of the bands was measured using the gray value and mean intensity tools in FIJI (ImageJ). Background signal was subtracted from each band measurement to obtain the final intensity values used for analysis.

- Data on tau levels in plasma and brain homogenates were obtained using commercial human-specific ELISA kits. The concentrations were measured following the manufacturers’ protocols. Absorbance was read at 450 nm using a FLUOstar OMEGA microplate reader (BMG Biotech), connected to a computer running MARS Data Analysis software (BMG Biotech). Standard curves were generated using the corresponding standard solutions provided in each kit, and absorbance values from samples were interpolated accordingly to calculate final concentrations. The ratio of each phosphorylated form of tau to total tau was calculated.

- Statistical analyses were performed using both GraphPad Prism (v 10.4.1, GraphPad Software Inc.) and R (v 3.6.2). In R, the following packages were used: rstatix (v 0.7.2), onewaytests (v 3.0), ggplot2 (v 3.4.1), and ggprism (v 1.0.4). For the analysis of learning performance in the Morris water maze, a nonlinear mixed-effects model was applied using Wright’s law, fitted with the nlme package (v 3.1). Colocalization analysis in double immunofluorescence images was performed by calculating Pearson's correlation coefficient using ImageJ software (NIH).


2. Data processing methods

All data were collected in an excel file divided in as many sections as the number of figures. Each excel includes: tables with the represented values in the graphics and, if applies, complete images of western blot membranes. 


3. Software or instruments needed to interpret the data:

The dataset is provided in .xlsx format; therefore, Microsoft Excel (or any compatible spreadsheet software, such as LibreOffice Calc or Google Sheets) is required to open and view the file.