In mice engineered to develop Alzheimer's-like pathology, Cerebrolysin — a peptide mixture with neurotrophic properties — restored the birth of new brain cells by protecting neural progenitor cells from dying.
Rescued neurogenesisCerebrolysin increased surviving new neurons and decreased apoptosis in Alzheimer's model mice without changing the cell birth rate
What the researchers found
APP transgenic mice (an Alzheimer's model) treated with Cerebrolysin for 1 and 3 months showed a significant increase in BrdU-positive cells and doublecortin-positive neuroblasts in the hippocampal subgranular zone compared to vehicle-treated APP mice.
Cerebrolysin also decreased TUNEL-positive and activated caspase-3-positive neural progenitor cells, indicating reduced apoptosis (programmed cell death). Notably, the number of proliferating cells (PCNA-positive) was unchanged, and the ratio of cells converting into neurons versus astroglia stayed the same.
This pattern suggests Cerebrolysin doesn't increase the birth rate of new cells but rather keeps them alive longer by preventing apoptosis, effectively rescuing the neurogenesis deficit seen in these Alzheimer's model mice.
Why it matters
One of the most devastating aspects of Alzheimer's is the progressive loss of brain cells and the failure to replace them. If a peptide therapy could protect the brain's remaining capacity to generate new neurons, it could complement other approaches targeting amyloid plaques or tau tangles. This study provides a mechanistic explanation for why Cerebrolysin has shown cognitive benefits in Alzheimer's animal models — it's not just protecting existing neurons but preserving the brain's regenerative capacity.
How the study worked
Transgenic mice expressing mutant amyloid precursor protein (APP) under the Thy-1 promoter were injected with BrdU (a marker that labels dividing cells) and treated with Cerebrolysin for 1 and 3 months. Researchers then counted various types of labeled cells in the hippocampal subgranular zone using immunohistochemistry — including markers for new cells (BrdU), immature neurons (doublecortin), cell death (TUNEL, caspase-3), and proliferation (PCNA). Results were compared between Cerebrolysin-treated and vehicle-treated transgenic mice, and non-transgenic controls.
What this study cannot tell us
This is a mouse study using a single transgenic Alzheimer's model, which doesn't fully replicate human Alzheimer's disease. Specific cell counts and statistical details are not provided in the abstract. The exact components of Cerebrolysin responsible for the neuroprotective effects are unclear since it's a complex peptide mixture. The study was published in 2007 and more recent work may have expanded on or challenged these findings.
How to read the evidence
This is a preclinical animal study using transgenic mice. While the experimental design includes appropriate controls and multiple cellular markers, the findings cannot be directly extrapolated to humans. The study provides mechanistic insight rather than clinical evidence.
When this study was published
Published in 2007, this is an older study. However, it remains a frequently cited reference for Cerebrolysin's neurogenesis effects. More recent research has continued to explore these mechanisms, and the basic findings about anti-apoptotic protection of neural progenitors have held up.
The bigger picture
Cerebrolysin has been used clinically in some countries for neurological conditions, though it remains controversial in Western medicine due to limited large-scale trial data. This study adds to a body of animal research suggesting the peptide mixture works through multiple mechanisms — not just protecting mature neurons but also supporting the birth and survival of new ones. The neurogenesis angle is particularly interesting because hippocampal neurogenesis is increasingly recognized as important for memory and cognitive function in aging.
Questions still open
- Would Cerebrolysin's neurogenesis-rescuing effect translate to human Alzheimer's patients, where the disease is more complex than in transgenic mouse models?
- Which specific peptide components within the Cerebrolysin mixture are responsible for the anti-apoptotic effect on neural progenitor cells?
- Could combining Cerebrolysin with amyloid-targeting therapies produce additive benefits by addressing both neurodegeneration and impaired neurogenesis?
Common questions
What is Cerebrolysin and how is it different from a single peptide drug?
Does this study prove Cerebrolysin can treat Alzheimer's disease?
Read the original research
Effects of Cerebrolysin on neurogenesis in an APP transgenic model of Alzheimer's disease.
Acta neuropathologica, 113(3), 265-75
Citation
Rockenstein, Edward; Mante, Michael; Adame, Anthony; Crews, Leslie; Moessler, Herbert; Masliah, Eliezer. (2007). Effects of Cerebrolysin on neurogenesis in an APP transgenic model of Alzheimer's disease.. Acta neuropathologica, 113(3), 265-75.