Delta-9-Tetrahydrocannabinol (∆9-THC) Induce Neurogenesis and Improve Cognitive Performances of Male Sprague Dawley Rats

THC is often associated with impaired memory, but its effects on the brain may depend heavily on dose and context. In this rat study, Δ9-THC enhanced markers involved in multiple stages of hippocampal neurogenesis and improved learning and memory performance, with the 1.5 mg/kg dose producing particularly strong effects on both neurogenesis and cognitive function.

“Neurogenesis is influenced by various external factors such as enriched environments. Some researchers had postulated that neurogenesis has contributed to the hippocampal learning and memory.

This project was designed to observe the effect of Delta-9-tetrahydrocannabinol (∆9-THC) in cognitive performance that influenced by the neurogenesis.

Different doses of ∆9-THC were used for observing the neurogenesis mechanism occurs in the hippocampus of rats. The brains were stained with antibodies, namely BrdU, glial fibrillary acidic protein (GFAP), nestin, doublecortin (DCX) and class III β-tubulin (TuJ-1). The cognitive test was used novel-object discrimination test (NOD) while the proteins involved, DCX and brain-derived neurotrophic factor (BDNF), were measured.

Throughout this study, ∆9-THC enhanced the markers involved in all stages of neurogenesis mechanism. Simultaneously, the cognitive behaviour of rat also showed improvement in learning and memory functions observed in behavioural test and molecular perspective.

Administration of ∆9-THC was observed to enhance the neurogenesis in the brain, especially in hippocampus thus improved the cognitive function of rats.”

https://pubmed.ncbi.nlm.nih.gov/28933048

“The treatment of 1.5 mg/kg of ∆9-THC has increase all the markers for neurogenesis and cognition function while improve the cognitive performance.”

https://link.springer.com/article/10.1007/s12640-017-9806-x

“Neurogenesis is the scientific term for the birth and growth of new brain cells.”

Need this THC study explained? thcXplained.com

Δ9-Tetrahydrocannabinol Modulates Hippocampal Neurogenesis in Female Wistar Rats: Interaction with Estradiol

THC may influence the female brain through both neurogenic and anti-inflammatory mechanisms. In ovariectomized female rats, Δ9-THC significantly increased hippocampal cell proliferation, showed evidence of enhanced neurogenesis, and reduced the inflammatory markers COX-2 and TNF-α. The effects also interacted with estradiol, highlighting the importance of hormonal status in determining THC’s actions in the brain.

“The endocannabinoid system (ECS) plays a key role in regulating neurogenesis and inflammatory processes in the brain.

The increasing prevalence of Cannabis use among women highlights the importance of understanding sex-specific effects of cannabinoids, particularly in the context of hormonal interactions.

This study aimed to investigate the effects of delta-9-tetrahydrocannabinol (THC) and estradiol benzoate (EB) on adult hippocampal neurogenesis (AHN) and inflammation in ovariectomized female Wistar rats.

Sixteen rats were allocated to four experimental groups receiving THC, EB, both treatments, and vehicle. Immunohistochemical analyses were conducted to evaluate markers of proliferation (Ki-67), neurogenesis (doublecortin and PSA-NCAM), cannabinoid receptor expression (CB1), and inflammation (COX-2 and TNF-α) in the hippocampal formation.

The administration of THC significantly increased Ki-67 immunoreactivity, suggesting enhanced cell proliferation. A trend toward increased doublecortin expression was observed, particularly in EB-treated animals. THC also modulated CB1 receptor expression, with significant increases in the dentate gyrus and hilus following combined THC and EB treatment. Furthermore, THC reduced inflammatory markers, with region-dependent decreases in COX-2 and TNF-α expression.

These findings indicate that THC influences markers associated with hippocampal cell proliferation, neurogenesis, cannabinoid signaling and inflammation in female rats, and that some of these effects depend on estradiol status.

The interaction between cannabinoids and gonadal hormones may represent an important mechanism underlying sex-specific neurobiological responses and suggests potential targets for therapeutic intervention in neuropsychiatric disorders.”

https://pubmed.ncbi.nlm.nih.gov/42570151

https://link.springer.com/article/10.1007/s11064-026-04857-w


Real-world quality of life and sleep outcomes in patients treated with THC- and CBD-rich Cannabis oil: a cross-sectional study

Patients using THC- and CBD-rich cannabis oil reported meaningful improvements in both sleep and overall quality of life in this real-world study. The findings suggest that cannabinoid-rich oil formulations may help address multiple symptom domains at once, particularly in patients dealing with persistent sleep disturbance and reduced day-to-day well-being.

“The endocannabinoid system plays an important role in the modulation of pain, mood, sleep, and subjective wellbeing. Despite the growing clinical use of medicinal Cannabis, real-world data simultaneously evaluating quality of life and sleep-related outcomes in heterogeneous clinical populations remain limited.

This study aimed to assess quality of life and sleep satisfaction in patients using medical Cannabis oil under supervised clinical follow-up. This cross-sectional observational study included patients treated with full-spectrum medical Cannabis oil rich in tetrahydrocannabinol (THC) and cannabidiol (CBD) in a real-world clinical setting.

Quality of life was assessed using the World Health Organization Quality of Life-BREF (WHOQOL-BREF), and sleep quality was evaluated using the Pittsburgh Sleep Quality Index (PSQI). Sociodemographic, clinical, and treatment-related data were collected via an electronic questionnaire. Nonparametric analyses, Spearman correlation, and ordinal logistic regression models were performed. Seventy-one participants were included, predominantly female, with diverse clinical conditions.

Participants reported generally favorable perceptions regarding quality of life and sleep satisfaction, with median scores concentrated in the higher response categories. Positive correlations were observed between the psychological domains of quality of life and sleep satisfaction.

Higher Cannabis oil concentrations and longer treatment duration were associated with higher odds of better outcomes.

In a real-world clinical context, supervised use of full-spectrum medical Cannabis oil was associated with favorable patient-reported perceptions of quality of life and sleep, consistent with perceived effectiveness.

These findings highlight the need for longitudinal studies with pre-treatment baseline assessment.”

https://pubmed.ncbi.nlm.nih.gov/42558508

“Cannabis sativa L. [Cannabaceae] has a documented history of medicinal use spanning thousands of years across diverse cultural and geographic contexts, with traditional applications encompassing pain relief, mood modulation, sleep induction, and the management of inflammatory and neurological conditions.”

“The growing integration of Cannabis into contemporary clinical practice reflects both the long-standing ethnopharmacological tradition associated with this species and the expanding body of evidence supporting the pharmacological activity of its principal phytocannabinoid metabolites, tetrahydrocannabinol (THC) and cannabidiol (CBD).”

“In summary, the results suggest that, in supervised clinical practice, patients using full-spectrum THC and CBD rich oil reported favorable perceived quality of life and sleep satisfaction.”

https://www.frontiersin.org/journals/pharmacology/articles/10.3389/fphar.2026.1862725/full


Δ8-THC Protects against Amyloid Beta Toxicity Modulating ER Stress In Vitro: A Transcriptomic Analysis

Amyloid-beta toxicity is a major driver of neuronal stress and degeneration in Alzheimer’s disease. In this laboratory study, Δ8-THC protected cells against amyloid-beta-induced damage and altered gene-expression pathways involved in endoplasmic reticulum stress. The results demonstrated that Δ8-THC might represent a new neuroprotective agent in Alzheimer’s disease.

“Alzheimer’s disease (AD) represents the most common form of dementia, characterized by amyloid β (Aβ) plaques and neurofibrillary tangles (NFTs). It is characterized by neuroinflammation, the accumulation of misfolded protein, ER stress and neuronal apoptosis. It is of main importance to find new therapeutic strategies because AD prevalence is increasing worldwide.

Cannabinoids are arising as promising neuroprotective phytocompounds.

In this study, we evaluated the neuroprotective potential of Δ8-THC pretreatment in an in vitro model of AD through transcriptomic analysis.

We found that Δ8-THC pretreatment restored the loss of cell viability in retinoic acid-differentiated neuroblastoma SH-SY5Y cells treated with Aβ1-42. Moreover, the transcriptomic analysis provided evidence that the enriched biological processes of gene ontology were related to ER functions and proteostasis. In particular, Aβ1-42 upregulated genes involved in ER stress and unfolded protein response, leading to apoptosis as demonstrated by the increase in Bax and the decrease in Bcl-2 both at gene and protein expression levels. Moreover, genes involved in protein folding and degradation were also deregulated. On the contrary, Δ8-THC pretreatment reduced ER stress and, as a consequence, neuronal apoptosis.

Then, the results demonstrated that Δ8-THC might represent a new neuroprotective agent in AD.”

https://pubmed.ncbi.nlm.nih.gov/37047608

“The results suggested that Δ8-THC may represent a novel neuroprotective agent in AD but also in other neurodegenerative diseases characterized by the accumulation of misfolded proteins.”

https://www.mdpi.com/1422-0067/24/7/6598

Cannabis-Based Nanolipid Formulations for Pain Management

Cannabinoids such as CBD and THC show promising analgesic effects, but poor stability and bioavailability can limit their therapeutic performance. This review found that nanoencapsulation may improve cannabinoid stability, delivery, and pain-relieving potential across acute, chronic, and neuropathic pain models. The authors concluded that cannabinoid nanoformulations could help support the development of more stable, safe, effective, and accessible therapies, particularly for chronic and neuropathic pain.

“Medicinal cannabis has gained increasing attention from both the scientific community and clinical practice, due to the therapeutic potential of its major phytocannabinoids, particularly cannabidiol (CBD) and Δ9-tetrahydrocannabinol (THC), for pain management.

This review compiled and analyzed the available evidence regarding the antinociceptive effects of nanoencapsulated cannabinoids compared to free compounds. The published works have explored some pharmaceutical formulations and administration routes on different acute, chronic and neuropathic pain experimental models.

The findings indicated that cannabinoids exhibited promising analgesic effects, while nanoencapsulation could enhance its stability and bioavailability.

Despite these advances, the number of reports investigating nanostructured cannabinoid-based systems remains limited, with a predominance of preclinical research. A recurrent lack of structural information and quality control data for such works was also noted. Furthermore, there were not identified any research regarding the nanoencapsulation of full-spectrum cannabis oils or whole cannabis extracts, highlighting a significant gap in the current literature.

Overall, nanoencapsulation emerges as a versatile strategy to overcome the intrinsic limitations of cannabinoids and expand its clinical applicability for pain treatment. Nevertheless, further efforts are required to determine standardized methodologies, facilitating the translation of preclinical findings into clinical practice, in order to provide stable, safe, effective and more accessible cannabinoid-based therapies.”

https://pubmed.ncbi.nlm.nih.gov/42514922

“Overall, advances in the nanoencapsulation of cannabinoids and other cannabis-derived products can significantly contribute to the development of stable, safe, effective and cost-effective pain therapies, particularly for chronic and neuropathic pain conditions.”

https://www.mdpi.com/1999-4923/18/7/844


Lower Pain Intensity Is Associated with the Use of Recreational Edible Cannabis Products Containing Delta-9-Tetrahydrocannabinol: A Secondary Analysis in Adults Self-Managing Their Chronic Low Back Pain

Adults using edible cannabis products to self-manage chronic low-back pain reported lower pain intensity on days they used products containing THC. Over 14 days, pain also declined among participants using products with relatively equal amounts of THC and CBD, with 36.6% achieving at least a 30% reduction in pain intensity. The researchers concluded that lower daily pain was associated specifically with THC-containing products, while higher CBD doses may attenuate some of THC’s pain-relieving association.

“Background/Objectives: Current literature regarding the efficacy of cannabis to reduce chronic pain intensity is mixed. Despite growing accessibility throughout the U.S., it is still unclear if the naturalistic use of recreational cannabis edible products is associated with decreases in pain intensity on days of use or longitudinally, and if these associations are dependent on the doses of delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD) being consumed. 

Methods: The trial (NCT03522324) from which these data were pulled was pre-registered in April 2018. Participants (N = 243; 56% female; mean age = 46 ± 12 years) with self-reported chronic low-back pain selected a recreational edible cannabis product to use exclusively, ad libitum, for 14 days. Labeled THC and CBD potency were used to determine product group: CBD-dominant (n = 97), THC + CBD (n = 112), or THC-dominant (n = 34). Participants completed daily surveys indicating current pain intensity (PROMIS; 0-10 scale), use or non-use of their product, and cannabinoid dose (THC and CBD). 

Results: Linear mixed effects showed a significant use × group interaction (p = 0.002), indicating that pain intensity was significantly lower on days of use in THC-dominant (b = -0.66, 95% CI [-0.94,-0.37]) and THC + CBD (b = -0.41, 95% CI [-0.57,-0.25]) groups compared to days when cannabis was not used. A significant group × time interaction (p = 0.02) indicated that pain intensity significantly decreased from day 1 to day 14 in those using THC + CBD products (b = -0.05, 95% CI [-0.07,-0.03]), with 36.6% of participants in the THC + CBD group experiencing ≥30% reduction in pain intensity from day 1 to day 14. Increasing doses of THC (b = -0.02, 95% CI [-0.04, -0.01]), not CBD (b = 0.003, 95% CI [-0.03, 0.01]), were associated with significantly lower pain intensity on days following product use, with increasing doses of CBD diminishing the impact of THC dose (b = 0.02, 95% CI [0.01, 0.04]). 

Conclusions: These findings indicate a complex relationship between THC, CBD, and pain intensity associated with the naturalistic use of recreational cannabis edible products. Lower daily pain intensity was associated with the use of products containing THC; however, dose models indicate that this association may be attenuated at higher doses of CBD. Additionally, only products containing relatively equal amounts of THC and CBD were associated with lower pain intensity after 14 days of observation.”

https://pubmed.ncbi.nlm.nih.gov/42512114

“Daily data collected over 14 days of naturalistic cannabis use demonstrated that reductions in participants’ current pain intensity were associated with the use of cannabis edible products, but only in products that contained THC. More frequent use of these products in the previous 24 h was associated with improved reductions in pain intensity.”

https://www.mdpi.com/2227-9059/14/7/1642


Nabiximols in Multiple Sclerosis: Beyond Spasticity-An Exploratory Systematic Review and Meta-Analysis of Symptomatic Outcomes

Nabiximols, a prescription cannabis-based oral spray containing approximately equal amounts of THC and CBD, is already used for treatment-resistant multiple sclerosis-related spasticity, but its benefits may extend further. In this systematic review and meta-analysis of 49 studies, nabiximols significantly improved bladder function, sleep disruption, spasm quality, gait function, and patients’ overall impression of change. The researchers concluded that nabiximols may provide broader symptomatic benefits in MS beyond spasticity, supporting the emerging “spasticity-plus” concept.

“Background/Objectives: Nabiximols, a standardized extract of Cannabis sativa, has been approved as an add-on therapy for patients with moderate to severe spasticity associated with multiple sclerosis (MS). Moreover, current Italian treatment algorithms suggest that cannabis-based therapies may have further relevance in the management of MS. The aim of our systematic review and meta-analysis was to assess the effectiveness of nabiximols in relieving symptoms other than spasticity in adult MS patients. 

Methods: A systematic search was conducted in Web of Science, MEDLINE (via PubMed), Cochrane CENTRAL and Embase on September 10, 2025. Study selection was performed according to the predefined PROSPERO protocol (CRD42022329952). Data were combined into a common denominator and examined using a random-effects model with meta-regression expressed as mean difference (MD) and a 95% confidence interval (CI). Risk of bias was assessed using the Cochrane risk of bias instrument (RoB2) and the Risk Of Bias In Non-randomized Studies of Interventions (ROBINS-I) tool. 

Results: Of the 49 eligible articles, 25 were included in the statistical analysis (2949 patients). Significant improvements in spasm quality (MD = -16.87; 95% CI = (-29.75)-(-3.99)), bladder function (MD = -16.38; 95% CI = (-22.18)-(-10.58)), sleep disruption (MD = -15.75; 95% CI = (-22.02)-(-9.49)) and gait function (timed walk MD(s) = -5.31; 95% CI(s) = (-9.88)-(-0.74)) were observed. Time-dependency was not significant. The subject global impression of change (SGIC) improved significantly after the first month (odds ratio (OR) = 1.69; 95% CI = (1.30)-(2.18)). 

Conclusion: Beyond spasticity, nabiximols may represent a signal of benefit for bladder function, sleep disruption, spasm quality, and gait function in MS, in line with the “spasticity-plus” concept. However, the evidence certainty was low to very low, and these findings should be considered exploratory.”

https://pubmed.ncbi.nlm.nih.gov/42506315

“Nabiximols is a well-characterized extract of Cannabis sativa (27 mg/mL tetrahydrocannabinol (THC) and 25 mg/mL cannabidiol (CBD)) that acts on the cannabinoid system. It is effective in treatment-resistant MS-related spasticity and may also improve several associated symptoms. Moreover, nabiximols has shown encouraging results in the treatment of various symptoms such as pain, gait function, sleep disruption, bladder function, fatigue, and tremors.”

https://www.mdpi.com/2076-3271/14/3/346


Preclinical antitumor evaluation of a tetrahydrocannabinol and cannabidiol (1:6) cannabis extract in an MCF-7 xenograft model of estrogen receptor-positive breast cancer

Estrogen receptor-positive breast cancer remains one of the most common forms of breast cancer, and new adjunctive treatment strategies are still needed. In this mouse xenograft study, a whole-cannabis extract containing THC and CBD in a 1:6 ratio significantly suppressed tumor growth, reduced tumor-cell proliferation, and increased apoptosis-related changes, with the highest dose producing the greatest reduction in tumor volume. The researchers concluded that the extract showed promising antiproliferative and antitumor activity and may warrant further investigation as an adjunctive approach for ER-positive breast cancer.

“Background and aim: Breast cancer remains one of the leading causes of cancer-related mortality worldwide, despite advances in surgery, chemotherapy, endocrine therapy, and targeted treatments. Cannabinoids derived from Cannabis sativa, particularly tetrahydrocannabinol (THC) and cannabidiol (CBD), have demonstrated anticancer properties in several experimental models; however, in vivo evidence in estrogen receptor (ER)-positive breast cancer remains limited. This study aimed to evaluate the antitumor effects of a THC:CBD (1:6) cannabis extract in a Michigan Cancer Foundation-7 breast cancer cell line (MCF-7) xenograft mouse model of ER-positive breast cancer.

Materials and methods: Female BALB/c nude mice bearing MCF-7 xenograft tumors were randomly assigned into five groups (n = 5/group): negative control (sesame oil), positive control treated with 5-fluorouracil (5-FU; 20 mg/kg), and three treatment groups receiving oral THC:CBD (1:6) extract at doses of 2, 10, or 20 mg/kg body weight for 30 consecutive days. Tumor growth was monitored throughout the experiment. Histopathological examination and immunohistochemical analysis of proliferating cell nuclear antigen (PCNA) expression were performed to evaluate apoptosis-related morphology and tumor cell proliferation. Hematological and biochemical parameters were assessed to determine systemic safety.

Results: Cannabinoid-treated groups exhibited significant suppression of tumor growth compared with the negative control group. Tumor volume reduction was observed in all treatment groups, with the greatest reduction detected in the high-dose THC:CBD group. Histopathological evaluation revealed increased numbers of tumor cells exhibiting morphological features consistent with apoptosis in cannabinoid-treated mice. Immunohistochemical analysis demonstrated significantly lower PCNA expression scores in all THC:CBD-treated groups compared with both negative and positive controls, indicating reduced tumor cell proliferation. Hematological parameters remained within normal physiological ranges in cannabinoid-treated animals. However, elevated alanine aminotransferase and aspartate aminotransferase levels were observed in the high-dose group, suggesting potential dose-related hepatic stress.

Conclusion: The THC:CBD (1:6) cannabis extract demonstrated significant antitumor activity in an MCF-7 xenograft model by suppressing tumor progression primarily through inhibition of tumor cell proliferation, with supportive apoptosis-related histological features. These findings provide novel in vivo evidence supporting the potential of cannabinoid-based formulations as adjunctive therapeutic approaches for ER-positive breast cancer.”

https://pubmed.ncbi.nlm.nih.gov/42494695

“In conclusion, the present study demonstrated that the THC:CBD (1:6) whole-cannabis extract exerted significant antitumor activity in an MCF-7 xenograft model of ER-positive breast cancer. Treatment with the cannabinoid extract resulted in marked suppression of tumor growth, significant reduction in tumor volume, decreased PCNA expression, and increased numbers of tumor cells exhibiting apoptosis-related morphological features.

Among the tested doses, the high-dose THC:CBD group showed the greatest reduction in tumor volume, indicating a strong antiproliferative effect of the cannabinoid formulation.”

“Overall, despite the inherent limitations of xenograft models, the present findings indicate that the THC:CBD (1:6) cannabis extract possesses promising antiproliferative and antitumor properties in ER-positive breast cancer. These results provide a foundation for future mechanistic and translational studies exploring cannabinoids as potential adjunctive agents in breast cancer therapy.”

https://veterinaryworld.org/Vol.19/June-2026/17.php

Prevention of Alzheimer’s Disease Pathology by Cannabinoids: Neuroprotection Mediated by Blockade of Microglial Activation

Alzheimer’s disease involves not only amyloid accumulation but also chronic activation of microglia and damaging neuroinflammation. In this preclinical study, cannabinoids reduced microglial activation, protected neurons from amyloid-related injury, and helped prevent Alzheimer’s-like pathology. The researchers concluded that cannabinoid-mediated suppression of microglial activation may represent a promising neuroprotective strategy for slowing or preventing disease progression.

“Alzheimer’s disease (AD) is characterized by enhanced β-amyloid peptide (βA) deposition along with glial activation in senile plaques, selective neuronal loss, and cognitive deficits.

Cannabinoids are neuroprotective agents against excitotoxicity in vitro and acute brain damage in vivo.

This background prompted us to study the localization, expression, and function of cannabinoid receptors in AD and the possible protective role of cannabinoids after βA treatment, both in vivo and in vitro.

Here, we show that senile plaques in AD patients express cannabinoid receptors CB1 and CB2, together with markers of microglial activation, and that CB1-positive neurons, present in high numbers in control cases, are greatly reduced in areas of microglial activation. In pharmacological experiments, we found that G-protein coupling and CB1 receptor protein expression are markedly decreased in AD brains. Additionally, in AD brains, protein nitration is increased, and, more specifically, CB1 and CB2 proteins show enhanced nitration. Intracerebroventricular administration of the synthetic cannabinoid WIN55,212-2 to rats prevent βA-induced microglial activation, cognitive impairment, and loss of neuronal markers.

Cannabinoids (HU-210, WIN55,212-2, and JWH-133) block βA-induced activation of cultured microglial cells, as judged by mitochondrial activity, cell morphology, and tumor necrosis factor-α release; these effects are independent of the antioxidant action of cannabinoid compounds and are also exerted by a CB2-selective agonist. Moreover, cannabinoids abrogate microglia-mediated neurotoxicity after βA addition to rat cortical cocultures.

Our results indicate that cannabinoid receptors are important in the pathology of AD and that cannabinoids succeed in preventing the neurodegenerative process occurring in the disease.”

“Cannabinoid receptors in AD brain.”

“Cannabinoids, the active components of marijuana and their analogs, exert a wide spectrum of central and peripheral effects by activating specific cannabinoid receptors, two of which have been well characterized to date: CB1 and CB2.”

“Cannabinoids exert neuroprotection under different experimental conditions. Thus, cannabinoid receptor activation protects hippocampal or granule cerebellar neurons from excitotoxicity”

“This background prompted us to study the characteristics and localization of cannabinoid receptors in AD brain, with particular emphasis on any relationship with microglial activation.”

“Cannabinoid treatment prevents βA-induced microglial activation and neurotoxicity in vitro.”

“Cannabinoid treatment prevents βA-induced toxic effects in vivo.”

“Because cannabinoids combine both anti-inflammatory and neuroprotective actions, our findings may set the basis for the use of these compounds as a therapeutic approach for AD.”

https://pmc.ncbi.nlm.nih.gov/articles/PMC6726060

https://www.jneurosci.org/content/25/8/1904.long

Delta-9-tetrahydrocannabinol delineates D-galactose and aluminium chloride-induced cognitive dysfunction and neurodegeneration in the hippocampus of the Wistar rat model

Cognitive decline and hippocampal neurodegeneration are closely linked to oxidative stress, inflammation, and neuronal damage. In this rat model, Δ9-THC improved learning and memory, reduced hippocampal neurodegeneration, and attenuated oxidative and inflammatory changes induced by D-galactose and aluminium chloride. The researchers concluded that THC showed neuroprotective potential and may warrant further investigation for disorders involving cognitive dysfunction and neurodegeneration.

“Alzheimer’s disease (AD) is a neurodegenerative disorder characterised by neurodegeneration and a decline in cognition and memory. D-galactose (D-gal) and aluminium chloride (AlCl3) have been used to induce cognitive deterioration in rat models that mimic the alterations observed in AD.

This study assessed the neurotherapeutic effect of Δ9-tetrahydrocannabinol (Δ9THC) on cognitive abilities, brain morphology, neurogenesis activity and neuropathological markers in Wistar rats induced by D-gal plus AlCl3.

Male albino Wistar rats received D-gal (60 mg/kg, intraperitoneally) and AlCl3 (200 mg/kg, orally) daily for 10 weeks. The rats were then treated with increasing concentrations of Δ9THC (0.75, 1.5 and 3.0 mg/kg) for 28 days. Cognitive performance was evaluated using the novel object recognition and modified elevated plus maze tests. Dentate gyrus viable granule cells, neurogenesis markers, amyloid precursor protein and phosphorylated tau (p‑tau Thr231) were assessed histologically and molecularly.

Δ9THC treatment improved cognitive performance, prevented granule cell loss in the dentate gyrus, increased neurogenesis-related markers (GFAP+, DCX+, calbindin+ and NeuN immunoreactivity), and reduced amyloid precursor protein and p‑tau Thr231 expression.

These findings suggest that Δ9THC possesses promising therapeutic potential against Alzheimer’s disease.”

https://pubmed.ncbi.nlm.nih.gov/42454694