What topics does this cannabis study cover?

This study covers research on: THC, Neuroprotection, Endocannabinoid.

Where was this research published?

Published in IBRO neuroscience reports on September 9, 2026.

THC extract improved memory in an Alzheimer’s-like rat model

Q: What did this research study find?

In an ovariectomized rat model of *Alzheimer’s-like cognitive impairment*, chronic treatment with a *THC*-standardized marijuana extract **improved spatial learning and memory deficits**.

Modulation of spatial learning and memory by cannabinoid-estrogen interaction in an AD-like cognitive impairment: The role of cannabinoid receptors and BDNF protein.

IBRO neuroscience reports • September 9, 2026 • Highly Relevant

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AI Summary

This abstract-based study asked whether a THC-containing marijuana extract could improve memory problems in an Alzheimer’s disease-like animal model, and whether estradiol changed the effect. Researchers used ovariectomized rats given an injection of amyloid-beta into the hippocampus to produce cognitive impairment. The animals received the extract for 28 days; the extract contained 8.5% Δ9-THC, corresponding to approximately 5.1 mg/kg/day Δ9-THC. Some animals also received estradiol. Spatial learning and memory were assessed with the Morris water maze, while hippocampal CB1, CB2, and BDNF measures were examined.

Chronic marijuana-extract treatment improved the induced deficits in spatial learning and memory. Changes in CB1 receptor expression and BDNF protein levels accompanied these behavioral findings, but the abstract does not establish that these molecular changes caused the memory improvement. Adding estradiol did not produce a synergistic effect, suggesting a complex interaction between cannabinoid- and estrogen-related signaling. The study was conducted in rats, not humans; the abstract does not report a sample size or quantitative effect sizes. Its most important limitations are that the extract was not fully chemically characterized and the mechanistic findings were correlational, so it cannot establish a treatment benefit or predict effects in people.

💡 Key Findings

In an ovariectomized rat model of Alzheimer’s-like cognitive impairment, chronic treatment with a THC-standardized marijuana extract improved spatial learning and memory deficits.

Moderate

55%

The behavioral changes were accompanied by alterations in hippocampal CB1 receptor expression and BDNF protein levels, but these findings were correlational rather than proof of mechanism.

Moderate

50%

Co-treatment with estradiol did not produce a synergistic effect with the marijuana extract.

Moderate

55%

The findings are preclinical and cannot establish whether the extract is effective or safe for people with Alzheimer’s disease or other memory disorders.

High

90%

📄 Original Abstract

Alzheimer's disease (AD) is an increasingly prevalent neurodegenerative disorder worldwide, with women showing a higher risk of developing the disease. The decline in steroid hormones after menopause may contribute to the increased susceptibility of women to neurodegenerative conditions. In parallel, cannabis-derived compounds have been reported to alleviate certain symptoms associated with neurological disorders. The present study was designed to investigate the effects of marijuana extract on cognitive impairment and hippocampal molecular markers in an ovariectomized AD-like rat model, and to evaluate whether co-administration with estradiol modifies these effects. The marijuana extract used in this study was characterized by HPLC and was found to contain 8.5% Δ9-THC. AD-like cognitive impairment pathology was induced by intra-hippocampal administration of Aβ25-35 in OVX rats. Animals were treated with marijuana extract (60 mg/kg/day, corresponding to approximately 5.1 mg/kg/day Δ9-THC) either alone or in combination with 17β-estradiol (1 mg/kg every 4 days) for 28 days. Cognitive performance was evaluated using the Morris water maze (MWM). In addition, hippocampal CB1/CB2 receptor expression and BDNF protein levels were measured to examine potential molecular associations. Our findings showed that chronic administration of the marijuana extract improved Aβ25-35-induced deficits in spatial learning and memory. Alterations in CB1 receptor expression and BDNF levels accompanied these behavioral effects. Notably, co-treatment with estradiol did not produce a synergistic effect, suggesting a complex interaction between cannabinoid-related and estrogen-related signaling pathways. These preclinical findings suggest that a THC-standardized marijuana extract may exert neuroprotective-like effects in an AD-like cognitive impairment model. However, because the extract was not fully phytochemically characterized and the mechanistic analyses were correlational, the results should be interpreted cautiously. Further studies are needed to clarify the underlying mechanisms and translational relevance of these findings.

Paper Type

📄 Research

Publication

Journal: IBRO neuroscience reports
Published: September 9, 2026
PMID: 42756662
DOI: 10.1016/j.ibneur.2026.09.002

Authors (4)

Mohammad Ali Mirshekar Clinical Immunology Research Center, Zahedan University of Medical Sciences, Zahedan, Iran.
Farzaneh Nadi Cellular and Molecular Research Center, Research Institute of Cellular and Molecular Sciences in Infectious Diseases, Zahedan University of Medical Sciences, Zahedan, Iran.
Hamed Fanaei Cellular and Molecular Research Center, Research Institute of Cellular and Molecular Sciences in Infectious Diseases, Zahedan University of Medical Sciences, Zahedan, Iran.
Mohadeseh Chahkandi Cellular and Molecular Research Center, Research Institute of Cellular and Molecular Sciences in Infectious Diseases, Zahedan University of Medical Sciences, Zahedan, Iran.