Molecular Neurobiology

, Volume 54, Issue 4, pp 2611–2621 | Cite as

Antidepressant-Like Effect of Ropren® in β-Amyloid-(25–35) Rat Model of Alzheimer’s Disease with Altered Levels of Androgens

  • Vagif Soultanov
  • Julia Fedotova
  • Tamara Nikitina
  • Victor Roschin
  • Natalia Ordyan
  • Lucian Hritcu


This study elucidated the potential antidepressant-like effect of prolonged Ropren® administration (8.6 mg/kg, orally, once daily for 28 days) using a β-amyloid (25–35) rat model of Alzheimer’s disease following gonadectomy. The experimental model was created by intracerebroventricular injection of β-amyloid (25–35) into gonadectomized (GDX) rats and GDX rats with testosterone propionate (TP, 0.5 mg/kg, subcutaneous, once daily, 28 days) supplementation. Ropren® was administered to the GDX rats and GDX rats treated with TP. Depression-like behavior was assessed in the forced swimming test, and the spontaneous locomotor activity was assessed using the open-field test. The corticosterone and testosterone levels in the blood serum before and after FST were measured in all experimental groups. Treatment with Ropren® significantly decreased the immobility time of GDX rats with β-amyloid (25–35) in the forced swimming test. Coadministration of Ropren® with TP exerted a markedly synergistic antidepressant-like effect in the GDX rats with β-amyloid (25–35 on the same model of depression-like behavior testing. Ropren® administered alone or together with TP significantly enhanced crossing, frequency of rearing, and grooming of the GDX rats with β-amyloid (25–35) in the open-field test. Moreover, Ropren® administered alone or together with TP significantly decreased the elevated corticosterone levels in the blood serum of GDX rats with β-amyloid (25–35) following the forced swimming test. These results indicate that Ropren® has a marked antidepressant-like effect in the experimental model of Alzheimer’s disease in male rats with altered levels of androgens.


Ropren® Polyprenols Testosterone Depression-like behavior Gonadectomy Alzheimer’s disease 



Dr. Julie Milland from Scribblers Inc. assisted with language editing of text. Solagran Limited supplied the Ropren® and funded the medical writer to edit the manuscript in English.

Compliance with Ethical Standards

All experiments were carried out in accordance with the Guide for Care and Use of Laboratory Animals, published by the National Institute of Health (National Research council, publication no. 85–23, revised in 1996), and the Animal Welfare Assurance Renewal for Pavlov Institute of Physiology. The rationale, design, and methods of this study were approved by the Ethical Committee for Animal Research, Pavlov Institute of Physiology, Russia.

Conflict of Interest

Dr. V. Soultanov is an academic scientist involved in decades of research into substances from conifer needles in Russia. He is a Director and shareholder of Solagran Limited, which is the company that is commercialising the technology. The authors have declared that no competing interests exist.


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Copyright information

© Springer Science+Business Media New York 2016

Authors and Affiliations

  1. 1.Solagran Limited, Biotechnology CompanySouth MelbourneAustralia
  2. 2.Laboratory of NeuroendocrinologyI.P. Pavlov Institute of Physiology of the Russian Academy of SciencesSt. PetersburgRussia
  3. 3.Laboratory of Comparative Somnology and NeuroendocrinologyI.M. Sechenov Institute of Evolutionary Physiology and Biochemistry of the Russian Academy of SciencesSt. PetersburgRussia
  4. 4.Department of Chemistry and Molecular BiologyITMO UniversitySt. PetersburgRussia
  5. 5.Laboratory of Functional Biochemistry of InvertebratesI.M. Sechenov Institute of Evolutionary Physiology and Biochemistry of the Russian Academy of SciencesSt. PetersburgRussia
  6. 6.Department of Wood ChemistryState Forest Technical AcademySt. PetersburgRussia
  7. 7.Department of BiologyAlexandru Ioan Cuza University of IasiIasiRomania

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