Investigation of Diagnostic Proteins by 2D Electrophoresis in Major Depression Model Induced by Forced Swim Test in Rats

Protein Pept Lett. 2021;28(2):195-204. doi: 10.2174/0929866527999200729183729.


Background: Aside from its pervasiveness, whereby it affects as much as 20% of the world's population, depression continues to be one of the most crucial psychiatric problems due to the loss of power it causes by disrupting daily life functioning, containing economic consequences, and having a high suicidal tendency. Major depression (MD) is a systemic and multifactorial disorder involving complex interactions between genetic predisposition and disturbances of various molecular pathways.

Objectives: In our current study, we aimed to identify the proteins obtained from serum samples that change during depression with the MD model.

Methods: The MD model was applied through the forced swim test in rats. 14 Winstar Albino male rats were divided into two equal groups as follows: depression and control groups. Serum samples were separated by chromatographic methods and then compared with two-dimensional (2D) electrophoresis.

Results: A total of 9 potential diagnostic protein sequences were identified, which were distinguished with computer software. During the last phase of the study, the Matrix-Assisted Laser Desorption/ Ionization - Time of Flight (MALDI-TOF) analysis, the previous expression sequences identified among the groups were determined and classified. By comparing protein expressions, it was concluded that 9 different points could be used together as a potential biomarker.

Conclusion: Results can help us identify a new diagnostic system that can be used to diagnose MD.

Keywords: 2D electrophoresis; Depression model; forcing swim test; major depression; protein; rats.

MeSH terms

  • Animals
  • Biomarkers / analysis
  • Biomarkers / metabolism*
  • Depressive Disorder, Major / diagnosis*
  • Depressive Disorder, Major / metabolism
  • Electrophoresis, Gel, Two-Dimensional / methods*
  • Male
  • Proteins / metabolism*
  • Proteome / analysis*
  • Proteome / metabolism*
  • Rats
  • Rats, Wistar
  • Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / methods
  • Swimming*


  • Biomarkers
  • Proteins
  • Proteome