Journal of Molecular Neuroscience

, Volume 66, Issue 3, pp 314–321 | Cite as

Carob (Ceratonia siliqua L.) Prevents Short-Term Memory Deficit Induced by Chronic Stress in Rats

  • Karem H. Alzoubi
  • Sanaa Alibbini
  • Omar F. Khabour
  • Tamam El-Elimat
  • Mohammad Al-zubi
  • Feras Q. AlaliEmail author


Long-term exposure to stressful conditions could impair the normal brain structure and function, specifically the hippocampus-dependent memory. This impairment could be attributed to a decrease in brain-derived neurotrophic factor (BDNF) levels during chronic stress. Knowing that carob [Ceratonia siliqua L. (Fabaceae)] is rich in a wide variety of polyphenols with a high antioxidant value, we hypothesized that the methanolic carob extract (C. siliqua) pods will prevent stress-induced memory impairment. Hence, the methanolic extract of carob pods was investigated for its ability to enhance learning and memory as well as to protect from memory impairment in normal stressed animals. Rats were chronically stressed for 7 weeks via the intruder stress model. Carob extract was administered to animals via intraperitoneal (i.p.) route at a daily dose of 50 mg/kg. Radial arm water maze (RAWM) was utilized to test for spatial learning and memory. In addition, brain tissues were dissected to determine BDNF levels. Chronic stress (CS) impaired short-term spatial memory (number of committed errors: P < 0.05, days to criterion (DTC): P < 0.001). Animal treatment with carob pod extract prevented the short-term memory impairment induced by CS (P < 0.05), while such treatment showed no effect on memory functions of unstressed rats. Moreover, carob pod extract prevented the reduction in the hippocampal BDNF (P < 0.05) induced by chronic stress exposure. In conclusion, CS impaired short-term memory function, while methanolic extract of carob pods prevented this impairment, probably as a result of preventing reduction in BDNF levels in the hippocampus.


Ceratonia silique Carob Stress Learning Memory Hippocampus Antioxidant BDNF 


Funding Information

Support for this work was provided from “the Deanship of Research, Jordan University of Science and Technology, Irbid, Jordan” (Grant No. 73/2008).

Compliance with Ethical Standards

The study protocol was approved by the Institutional Animal Care and Use Committee at JUST.

Conflict of Interest

The authors declare that they have no conflict of interest.


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Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2018
corrected publication 2018

Authors and Affiliations

  1. 1.Department of Clinical Pharmacy, Faculty of PharmacyJordan University of Science and TechnologyIrbidJordan
  2. 2.Department of Medicinal Chemistry and Pharmacognosy, Faculty of PharmacyJordan University of Science and TechnologyIrbidJordan
  3. 3.Department of Medical Laboratory SciencesJordan University of Science and TechnologyIrbidJordan
  4. 4.Department of PathologyVirginia Commonwealth UniversityRichmondUSA
  5. 5.College of PharmacyQatar UniversityDohaQatar

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