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Background: Signal Peptide Peptidase‐Like 2b (SPPL2b) is relevant for AD, being a brain‐specific intramembrane protein involved in the cleavage of Alzheimer's disease (AD)‐related proteins, such as BRI2, inflammatory‐related proteins like CD74, TNFalpha, and Clec7a, and synaptic proteins Neuregulin‐1 and VAMP 1‐4. SPPL2b is specifically expressed in the hippocampus and cortex. The cleavage of TNFalpha by SPPL2b promotes the inflammatory pathway. Conversely, the SPPL2b substrate BRI2 regulates amyloid precursor protein (APP) cleavage and subsequent Aβ production. This work explores the pathophysiological role of SPPL2b in AD pathogenesis and investigates the potential of inhibiting SPPL2b activity as a novel therapeutic strategy. Method: To characterize the role of SPPL2b in the APP cleavage process and neuroinflammation, we used neurons and glia primary cell cultures from WT and SPPL2b‐deficient mice. Furthermore, we assessed the therapeutic potential of inhibiting SPPL2b by employing a new AD mouse model generated through crossbreeding state‐of‐the‐art AppNL‐G‐F knock‐in mice with SPPL2b‐deficient mice. Cells and mouse brain samples were analyzed through western blotting, immunoprecipitation, and immunofluorescence. Aβ levels were quantified using ELISA kits. Result: The results showed a significant increase in BRI2, followed by a substantial reduction in soluble APP, Aβ40, and Aβ42 levels in the conditioned media of SPPL2b KO neurons. Immunoprecipitation of BRI2 from the cortex of those mice revealed an increased interaction between BRI2 and APP in SPPL2b KO/AppNL‐G‐F mice. Most importantly, a notable decrease in brain Aβ plaque deposition and a significant decrease in both cortical and hippocampal gliosis were observed at 4 months‐of‐age in SPPL2b KO/AppNL‐G‐F mice. Conclusion: The results outlined in this study support a relevant connection between SPPL2b and the development of Aβ pathology in AD. In a global scenario characterized by the need to identify novel strategies to prevent and counteract AD progression, this study highlights and strengthens the importance of SPPL2b as a novel therapeutic approach for AD. [ABSTRACT FROM AUTHOR]

Background: High age is the biggest risk factor for Alzheimer's disease (AD). Approved drugs that slow down the aging process have the potential to be repurposed for the primary prevention of AD. The aim of our project was to use a reverse translational approach to identify such drug candidates in epidemiological data followed by validation in cell‐based models and animal models of aging and AD. Method: Longitudinal samples from a Swedish twin cohort (N = 672) were used to assess the effects of commonly prescribed medications on biological aging. Mendelian Randomization was used to identify associations between genetic variations in the glucagon‐like peptide 1 (GLP‐1) analogues target and the risk of developing AD. The identified classes of compounds were next evaluated in a pipe line of cellular and animal models for their potency of increasing lifespan using C. elegans models expressing amyloidbeta (Aβ) and tau, and for lowering Aβ levels in neuroblastoma SH‐SY5Y cells and AD‐associated pathologies in AppNL‐F knock‐in mice as well as their anti‐aging effects in a novel mouse model of CNS aging. Result: We found that initiation of calcium channel blockers (CCBs) was associated with about a two‐year decrease in multiple epigenetic clocks (DNA methylation ages) as well as in functional biological ages. Moreover, genetic variants in GLP‐1 targets were associated with lower risk of developing AD. Several of the clinically used CCBs significantly increased the life span in C. elegans Aβ model and decreased levels of secreted Aβ from SH‐SY5Y cells. Several GLP‐1 analogues, similar to the CCBs, demonstrated a positive effect in reducing Aβ42 levels in SH‐SY5Y cell media. Conclusion: These preliminary data, demonstrating an extension of lifespan and a reduction in Aβ42 production, support the potential repurposing strategy for CCBs and GLP‐1 analogs in slowing down aging and preventing/treating AD. The investigation of these compounds in mouse models of aging and AD will provide a more complete picture of the therapeutic potential and may eventually identify novel preventive measures for AD within CCB and GLP‐1 analogs. [ABSTRACT FROM AUTHOR]

Background: Alzheimer's disease (AD) is an age-related disease characterized by altered cognition, neuroinflammation, and neurodegeneration against which there is presently no effective cure. Brain-derived neurotrophic factor (BDNF) is a key neurotrophin involved in the learning and memory process, with a crucial role in synaptic plasticity and neuronal survival. Several findings support that a reduced BDNF expression in the human brain is associated with AD pathogenesis. BDNF has been proposed as a potential therapy for AD, but BDNF has low brain penetration. In this study, we used an innovative encapsulated cell biodelivery (ECB) device, containing genetically modified cells capable of releasing BDNF and characterized its feasibility and therapeutic effects in the novel App knock-in AD mouse model (AppNL−G−F). Methods: ECB's containing human ARPE-19 cells genetically modified to release BDNF (ECB-BDNF devices) were stereotactically implanted bilaterally into hippocampus of 3-month-old AppNL−G−F mice. The stability of BDNF release and its effect on AD pathology were evaluated after 1, 2-, and 4-months post-implantation by immunohistochemical and biochemical analyses. Exploratory and memory performance using elevated plus maze (EPM) and Y-maze test were performed in the 4-months treatment group. Immunological reaction towards ECB-BDNF devices were studied under ex vivo and in vivo settings. Results: The surgery and the ECB-BDNF implants were well tolerated without any signs of unwanted side effects or weight loss. ECB-BDNF devices did not induce host-mediated immune response under ex vivo set-up but showed reduced immune cell attachment when explanted 4-months post-implantation. Elevated BDNF staining around ECB-BDNF device proximity was detected after 1, 2, and 4 months treatment, but the retrieved devices showed variable BDNF release. A reduction of amyloid-β (Aβ) plaque deposition was observed around ECB-BDNF device proximity after 2-months of BDNF delivery. Conclusions: The result of this study supports the use of ECB device as a promising drug-delivery approach to locally administer BBB-impermeable factors for treating neurodegenerative conditions like AD. Optimization of the mouse-sized devices to reduce variability of BDNF release is needed to employ the ECB platform in future pre-clinical research and therapy development studies. [ABSTRACT FROM AUTHOR]

Simple Summary: Alzheimer's disease (AD) is a complex, multifactorial disease where numerous components, such as environment, lifestyle, comorbidities, and genetic predisposition, contribute to triggering the onset of the disease. Several neurobiological brain alterations have been reported during AD pathologies, including the endocannabinoid system (ECS) and associated lipid transmitter-based signaling systems. In this study, we have evaluated the expression levels of the cannabinoid receptors type 2 (CB2) and the novel cannabinoid/lysophospholipid G protein-coupled receptor 55 (GPR55) at different stages of AD. We deeply investigated CB2 and GPR55's close proximity with Aβ-plaque deposits, as well as neuronal and glial cells, in the AD AppNL-G-F knock-in mouse model. Additionally, we analyzed whether Aβ42 directly affects CB2 and GPR55 protein expression in neuronal and glial primary cell cultures. Our study shows that the ECS, specifically the CB2 and GPR55 receptors, are altered during AD pathology. Monitoring these receptors may provide new biomarkers for AD diagnosis. CB2 and GPR55 could be potential pharmacological targets for selective compounds to treat AD inflammation. Background: The endocannabinoid system (ECS) and associated lipid transmitter-based signaling systems play an important role in modulating brain neuroinflammation. ECS is affected in neurodegenerative disorders, such as Alzheimer's disease (AD). Here we have evaluated the non-psychotropic endocannabinoid receptor type 2 (CB2) and lysophosphatidylinositol G-protein-coupled receptor 55 (GPR55) localization and expression during Aβ-pathology progression. Methods: Hippocampal gene expression of CB2 and GPR55 was explored by qPCR analysis, and brain distribution was evaluated by immunofluorescence in the wild type (WT) and APP knock-in AppNL-G-F AD mouse model. Furthermore, the effects of Aβ42 on CB2 and GPR55 expression were assessed in primary cell cultures. Results: CB2 and GPR55 mRNA levels were significantly upregulated in AppNL-G-F mice at 6 and 12 months of age, compared to WT. CB2 was highly expressed in the microglia and astrocytes surrounding the Aβ plaques. Differently, GPR55 staining was mainly detected in neurons and microglia but not in astrocytes. In vitro, Aβ42 treatment enhanced CB2 receptor expression mainly in astrocytes and microglia cells, whereas GPR55 expression was enhanced primarily in neurons. Conclusions: These data show that Aβ pathology progression, particularly Aβ42, plays a crucial role in increasing the expression of CB2 and GPR55 receptors, supporting CB2 and GPR55 implications in AD. [ABSTRACT FROM AUTHOR]

Alzheimer's disease (AD) is characterized by impaired protein homeostasis leading to amyloid-β peptide (Aβ) amyloidosis. Amyloid precursor protein (APP) knock-in mice exhibit robust Aβ pathology, providing possibilities to determine its effect on protein homeostasis including autophagy. Here we compared human AD postmortem brain tissue with brains from two different types of App knock-in mice, App NL – F and App NL – G – F mice, exhibiting AD-like pathology. In AD postmortem brains, p62 levels are increased and p62-positive staining is detected in neurons, including potential axonal beadings, as well as in the vasculature and in corpora amylacea. Interestingly, p62 is also increased in the neurons in 12-month-old App NL – G – F mice. In brain homogenates from 12-month-old App NL – G – F mice, both p62 and light chain 3 (LC3)-II levels are increased as compared to wildtype (WT) mice, indicating inhibited autophagy. Double immunostaining for LC3 and Aβ revealed LC3-positive puncta in hippocampus of 24-month-old App NL – F mice around the Aβ plaques which was subsequently identified by electron microscopy imaging as an accumulation of autophagic vacuoles in dystrophic neurites around the Aβ plaques. Taken together, autophagy is impaired in App knock-in mice upon increased Aβ pathology, indicating that App knock-in mouse models provide a platform for understanding the correlation between Aβ and autophagy. [ABSTRACT FROM AUTHOR]

Emotional behavior, memory, and learning have been associated with alterations in the immune system in neuropsychiatric and neurodegenerative diseases. In recent years, several studies pointed out the involvement of the cannabinoid receptor 2 (CB2r) in the immune system and the regulation of inflammation. This receptor is widely distributed in different tissues and organs with higher expression in spleen and immune system cells. However, CB2r has also been detected in several brain areas and different brain cell types, such as neurons and glia. These findings suggest that CB2r may closely relate the immune system and the brain circuits regulating inflammation, mood, and cognitive functions. Therefore, we review the studies that may help elucidate the molecular bases of CB2r in regulating inflammation in different brain cells and its role in the pathophysiology of psychiatric and neurodegenerative disorders. [ABSTRACT FROM AUTHOR]

Background: Altered cholinergic pathways and memory dysfunction are well‐known changes during Alzheimer's disease (AD), linked to the early loss of basal forebrain cholinergic neurons (BFCNs). BFCN's innervates wide regions of the brain, including hippocampus which is a crucial site of neurotrophic factor production like nerve growth factor (NGF) – the master regulator of cholinergic pathways and brain derived neurotrophic factor (BDNF). Hippocampus coordinates memory and cognition and is found affected with amyloid‐beta (Aβ) pathology in AD. Till date, a clear connection between Aβ pathology in modulating cholinergic alteration has not been proven. Recently, the anti‐amyloid antibody Aducanumab and Lecanemab was approved for AD therapy by the United States of America Food and Drug Administration but whether Aβ deposition or clearance modulates cholinergic activity is not established. We evaluated cholinergic status in hippocampus of AD mice model in‐comparison with matched wildtype control. Method: Hippocampus tissue was isolated from a humanized APP‐knock‐in mouse model of AD (AppNL‐G‐F) at different stages of amyloid pathology – 2‐month age (pre‐plaque stage), 7‐month age (plaques present + initiation of cognitive deficits), and 12‐month age (advanced amyloid pathology), and age‐matched wildtype control (C57BL/6JRj) respectively. Tissues were then processed to isolate total protein which was achieved by extracting them in various buffers (soluble, ionic, and detergent soluble fractions) and pooled together. Enzyme assays for cholinergic markers including acetylcholinesterase (AChE), butyrylcholinesterase (BuChE), choline acetyltransferase (ChAT) was performed, along with ELISA for the estimation of total NGF and BDNF levels, respectively. Result: Age‐dependent changes were observed in AppNL‐G‐F mice compared to wild‐type controls. Cholinesterase activity was increased for AChE at 7 months, while BuChE activity was less in the AppNL‐G‐F mice from 7 month onwards, with respect to wildtype control mice respectively. ChAT levels were nominally affected but the cholinergic index (ChAT/AChE) was considerably altered in AppNL‐G‐F mice. NGF levels remained unchanged, but BDNF levels increased in an age‐dependent manner in AppNL‐G‐F mice as compared to control mice. Conclusion: Significant age‐dependent alteration in cholinergic activity and neurotrophic factors were evident in hippocampus tissue of AppNL‐G‐F mice, when compared to wild‐type counterparts underlining the importance of the cholinergic activity in relation to amyloid pathology. [ABSTRACT FROM AUTHOR]

Background: Increasing epidemiological, clinical, and experimental evidence suggests that Alzheimer's disease (AD) pathogenesis is closely associated with systemic abnormalities, including dynamic processes in the peripheral immune compartment and inflammation1,2,3. Recent reports in transgenic AD animal models propose a role of dysregulated peripheral immune system in memory impairment4,5. In this regard, the contribution of peripheral immune response in driving different pathological stages in AD is less understood. Therefore, utilizing a novel App knock‐in mouse model (AppNL‐G‐F) exhibiting robust Aβ pathology, neuroinflammation and memory impairment, we have explored the relation of Aβ pathology development in the brain with alterations in the peripheral immune compartment. Method: Using flowcytometry, we characterized the AppNL‐G‐F mice at different stages of Aβ pathology (early‐plaque: 3‐month‐old; plaque + early memory impairment: 7‐month‐old; late stages: 12‐month‐old) and investigated the distribution and activation status of various peripheral immune cells in splenic primary cells. Result: Among various immune cells from innate immunity including macrophages, natural killer and dendritic cells, there was a significant increase in macrophage number in AppNL‐G‐F mice. While percent distribution of B cells from adaptive immunity was reduced (as observed in AD patients2), no significant changes in total T cell distribution following 3, 7 and 12‐months of age compared to wild‐type controls was observed. B cells showed reduced activation examined by CD69 and PD‐L1 expression in 7 and 12‐months old AppNL‐G‐F mice. Among T cell subsets, CD4, CD8 and regulatory T (Treg) cell distribution in AppNL‐G‐F mice was comparable to control mice in all age groups. However, there was rise in follicular T helper (Tfh) cells at 3‐month of age, with altered activation molecule ICOS expression in AppNL‐G‐Fmice. Conclusion: These findings in AD mice model show a reduction in B cell and their activation status during aggressive Aβ plaque deposition in brain, reflecting their possible contribution in Aβ pathology reinforcing the importance of further investigation. Our data suggest a possible role of Tfh cell in early stage of Aβ pathology. An altered Tfh cell activation may answer the impaired protective antibody production from B cells reported in AD6,7. The observed increase in macrophages in the peripheral system during Aβ pathology development demands further investigation. [ABSTRACT FROM AUTHOR]

The use of different natural and/or synthetic preparations of Cannabis sativa is associated with therapeutic strategies for many diseases. Indeed, thanks to the widespread diffusion of the cannabinoidergic system in the brain and in the peripheral districts, its stimulation, or inhibition, regulates many pathophysiological phenomena. In particular, central activation of the cannabinoidergic system modulates the limbic and mesolimbic response which leads to food craving. Moreover, cannabinoid agonists are able to reduce inflammatory response. In this review a brief history of cannabinoids and the protagonists of the endocannabinoidergic system, i.e. synthesis and degradation enzymes and main receptors, will be described. Furthermore, the pharmacological effects of cannabinoids will be outlined. An overview of the involvement of the endocannabinoidergic system in neuroinflammatory and metabolic pathologies will be made. Finally, particular attention will also be given to the new pharmacological entities acting on the two main receptors, cannabinoid receptor type 1 (CB1) and cannabinoid receptor type 2 (CB2), with particular focus on the neuroinflammatory and metabolic mechanisms involved. [ABSTRACT FROM AUTHOR]

Protein misfolding and aggregation is increasingly being recognized as a cause of disease. In Alzheimer's disease the amyloid-β peptide (Aβ) misfolds into neurotoxic oligomers and assembles into amyloid fibrils. The Bri2 protein associated with Familial British and Danish dementias contains a BRICHOS domain, which reduces Aβ fibrillization as well as neurotoxicity in vitro and in a Drosophila model, but also rescues proteins from irreversible nonfibrillar aggregation. How these different activities are mediated is not known. Here we show that Bri2 BRICHOS monomers potently prevent neuronal network toxicity of Aβ, while dimers strongly suppress Aβ fibril formation. The dimers assemble into high-molecular-weight oligomers with an apparent two-fold symmetry, which are efficient inhibitors of non-fibrillar protein aggregation. These results indicate that Bri2 BRICHOS affects qualitatively different aspects of protein misfolding and toxicity via different quaternary structures, suggesting a means to generate molecular chaperone diversity. [ABSTRACT FROM AUTHOR]

Background: Alzheimer's disease (AD) is an age‐related disease characterized by synaptic dysfunction, brain inflammation, and neurodegeneration against which there is no effective cure available. Brain‐Derived Neurotrophic Factor (BDNF) is a key molecule involved in the learning and memory process, with a crucial role in synaptic plasticity and neuronal survival. Several findings support that a reduced BDNF expression in the human brain is associated with AD pathogenesis. BDNF has been proposed as a potential therapy for AD, but BDNF has low brain permeability. In this study, we used an innovative encapsulated cell biodelivery (ECB) device containing cells capable of locally delivering BDNF to characterize its neuroprotective effects in the novel AD APP‐knock‐in mouse model AppNL‐G‐F. Method: ECB devices with human ARPE‐19 cells modified to release BDNF were surgically bilaterally implanted in the hippocampus of 3‐month‐old AppNL‐G‐F mice. BDNF effects on AD pathology were evaluated after 1, 2, and 3 months of treatment by immunohistochemical and biochemical analysis. In the 3‐month‐treated groups, exploratory and memory performances were also evaluated using Elevated Plus Maze (EPM) and Y‐maze tests. Result: The ECB implants were well tolerated with no signs of unwanted side effects or weight loss. A high BDNF staining was detected in most of the brains in the area surrounding the devices at 1‐3 months, but retrieved devices showed variability of BDNF release. Interestingly, three months of BDNF treatment significantly improved AppNL‐G‐F mice´s anxiety behavior in EPM and improved the spontaneous behavioral alternations in the Y‐maze test. Conclusion: The results of this study are encouraging and support the BDNF device as a promising approach for treating cognitive AD decline. Optimization of the mouse‐sized devices to reduce the variability of BDNF release is needed for future experiments and translated to larger devices for clinical translation. [ABSTRACT FROM AUTHOR]

Cogent evidence shows that cannabis plays a variable role on behavioral regulation and the pathophysiology of most psychiatric conditions. Accordingly, cannabis has been alternatively shown to exacerbate or ameliorate mental symptoms, depending on its composition and route of consumption, as well as specific individual and contextual characteristics. The vulnerability to the psychological effects of cannabis is influenced by a complex constellation of genetic and environmental factors. In the present article, we will review the current evidence on the pharmacological, individual and situational factors that have been documented to affect the behavioral and psychiatric effects of cannabinoids. [ABSTRACT FROM AUTHOR]

Background: Alzheimer's disease (AD) is a multifactorial disorder in which the abnormal brain production of amyloid β‐peptide (Aβ) plays a crucial role in its onset. Identifying new mechanisms and proteins involved in AD pathogenesis is critical to finding novel effective disease‐altering therapeutic targets. The intramembrane enzyme Signal Peptide Peptidase Like 2b (SPPL2b), which belongs to the same protein family as presenilin, is a new potential target since it is involved in the proteolysis of two AD‐related proteins: TNF‐alpha and BRI2 involved in the inflammatory response and Aβ production respectively. Here we have investigated for the expression levels and the pathogenic role of SPPL2b in AD. Method: The pathophysiological role of SPPL2b in Aβ metabolism was evaluated in vitro by using human cell lines SH‐SY5Y and HEK293 stably expressing APP, in acute brain slices from WT mice, in brains of a new APP knock‐in AD mouse model (AppNL‐G‐F) and humans post mortem AD brain tissues. Result: APP overexpression in SH‐SY5Y cells increased SPPL2b expression, which was paralleled by reduced BRI2 levels. A reduction in Aβ40 production was observed in SH‐SY5Y cells after inhibiting SPPL2b activity. In brain slices maintained ex vivo, Aβ42 exposure induced a strong upregulation of SPPL2b. Increased levels of SPPL2b were also observed in the cortex in the early stage of the AD‐associated Aβ pathology of 3 months old AppNL‐G‐F. On the contrary, a lower SPPL2b expression was observed in 10 months old AppNL‐G‐F mice, when Aβ pathology is severe and accompanied by neuroinflammation, and similarly decreased in humans AD post mortem cortex. Furthermore, immunofluorescence staining showed that SPPL2b is expressed in neurons and glia deposited in the amyloid plaque, indicating a direct role of SPPL2b in Aβ plaques formation. Conclusion: These results strongly support the involvement of SPPL2b in AD pathology, and most important Aβ42 is directly involved in SPPL2b expression. Modulation of the SPPL2b activity, could be potentially beneficial in preventing both Aβ neurotoxicity and neuroinflammation. The brain‐specificity and the few substrates related make of SPPL2b an attractive therapeutic target. [ABSTRACT FROM AUTHOR]

Simple Summary: This review was aimed at exploring the potentiality of drugging the endocannabinoid system as a therapeutic option for Alzheimer's disease (AD). Recent discoveries have demonstrated how the modulation of cannabinoid receptor 1 (CB1) and receptor 2 (CB2) can exert neuroprotective effects without the recreational and pharmacological properties of Cannabis sativa. Thus, this review explores the potential of cannabinoids in AD, also highlighting their limitations in perspective to point out the need for further research on cannabinoids in AD therapy. Alzheimer's disease (AD) is a detrimental brain disorder characterized by a gradual cognitive decline and neuronal deterioration. To date, the treatments available are effective only in the early stage of the disease. The AD etiology has not been completely revealed, and investigating new pathological mechanisms is essential for developing effective and safe drugs. The recreational and pharmacological properties of marijuana are known for centuries, but only recently the scientific community started to investigate the potential use of cannabinoids in AD therapy—sometimes with contradictory outcomes. Since the endocannabinoid system (ECS) is highly expressed in the hippocampus and cortex, cannabis use/abuse has often been associated with memory and learning dysfunction in vulnerable individuals. However, the latest findings in AD rodent models have shown promising effects of cannabinoids in reducing amyloid plaque deposition and stimulating hippocampal neurogenesis. Beneficial effects on several dementia-related symptoms have also been reported in clinical trials after cannabinoid treatments. Accordingly, future studies should address identifying the correct therapeutic dosage and timing of treatment from the perspective of using cannabinoids in AD therapy. The present paper aims to summarize the potential and limitations of cannabinoids as therapeutics for AD, focusing on recent pre-clinical and clinical evidence. [ABSTRACT FROM AUTHOR]

Abstract Ethnopharmacological relevance Cannabis sativa L. (C. sativa) is an annual dioecious plant, which shares its origins with the inception of the first agricultural human societies in Asia. Over the course of time different parts of the plant have been utilized for therapeutic and recreational purposes, for instance, extraction of healing oils from seed, or the use of inflorescences for their psychoactive effects. The key psychoactive constituent in C. sativa is called Δ-9-tetrahydrocannabinol (D9-THC). The endocannabinoid system seems to be phylogenetically ancient, as it was present in the most primitive vertebrates with a neuronal network. N-arachidonoylethanolamine (AEA) and 2-arachidonoyl glycerol (2-AG) are the main endocannabinoids ligands present in the animal kingdom, and the main endocannabinoid receptors are cannabinoid type-1 (CB1) receptor and cannabinoid type-2 (CB2) receptor. Aim of the study The review aims to provide a critical and comprehensive evaluation, from the ancient times to our days, of the ethnological, botanical, chemical and pharmacological aspects of C. sativa, with a vision for promoting further pharmaceutical research to explore its complete potential as a therapeutic agent. Materials and methods This study was performed by reviewing in extensive details the studies on historical significance and ethnopharmacological applications of C. sativa by using international scientific databases, books, Master's and Ph.D. dissertations and government reports. In addition, we also try to gather relevant information from large regional as well as global unpublished resources. In addition, the plant taxonomy was validated using certified databases such as Medicinal Plant Names Services (MPNS) and The Plant List. Results and conclusions A detailed comparative analysis of the available resources for C. sativa confirmed its origin and traditional spiritual, household and therapeutic uses and most importantly its popularity as a recreational drug. The result of several studies suggested a deeper involvement of phytocannabinoids (the key compounds in C. sativa) in several others central and peripheral pathophysiological mechanisms such as food intake, inflammation, pain, colitis, sleep disorders, neurological and psychiatric illness. However, despite their numerous medicinal benefits, they are still considered as a menace to the society and banned throughout the world, except for few countries. We believe that this review will help lay the foundation for promoting exhaustive pharmacological and pharmaceutical studies in order to better understand the clinical relevance and applications of non-psychoactive cannabinoids in the prevention and treatment of life-threatening diseases and help to improve the legal status of C. sativa. Graphical abstract fx1 [ABSTRACT FROM AUTHOR]

Alzheimer's disease (AD) is the most common form of dementia and there is no successful treatment available. Evidence suggests that fibril formation of the amyloid β-peptide (Aβ) is a major underlying cause of AD, and treatment strategies that reduce the toxic effects of Aβ amyloid are sought for. The BRICHOS domain is found in several proteins, including Bri2 (also called integral membrane protein 2B (ITM2B)), mutants of which are associated with amyloid and neurodegeneration, and Bri3 (ITM2C). We have used mouse hippocampal neurons and brain tissues from mice and humans and show Bri3 deposits dispersed on AD plaques. In contrast to what has been shown for Bri2, Bri3 immunoreactivity is decreased in AD brain homogenates compared to controls. Both Bri2 and Bri3 BRICHOS domains interact with Aβ 40 and Aβ 42 present in neurons and reduce Aβ 42 amyloid fibril formation in vitro , but Bri3 BRICHOS is less efficient. These results indicate that Bri2 and Bri3 BRICHOS have different roles in relation to Aβ aggregation.

Protein misfolding and aggregation is increasingly being recognized as a cause of disease. In Alzheimer's disease the amyloid-β peptide (Aβ) misfolds into neurotoxic oligomers and assembles into amyloid fibrils. The Bri2 protein associated with Familial British and Danish dementias contains a BRICHOS domain, which reduces Aβ fibrillization as well as neurotoxicity in vitro and in a Drosophila model, but also rescues proteins from irreversible non-fibrillar aggregation. How these different activities are mediated is not known. Here we show that Bri2 BRICHOS monomers potently prevent neuronal network toxicity of Aβ, while dimers strongly suppress Aβ fibril formation. The dimers assemble into high-molecular-weight oligomers with an apparent two-fold symmetry, which are efficient inhibitors of non-fibrillar protein aggregation. These results indicate that Bri2 BRICHOS affects qualitatively different aspects of protein misfolding and toxicity via different quaternary structures, suggesting a means to generate molecular chaperone diversity.

The synthesis of three series of novel 4-alkyl-5-(5'-chlorothiophen-2'-yl)-pyrazole-3-carbamoyl analogues of rimonabant with affinity for the CB1 cannabinoid receptor subtype is reported. Amongst the novel derivatives, compounds 21j, 22a, 22c, and 22f showed affinity values expressed as Ki ranging from 5.5 to 9.0 nM. Derivative 23e revealed a good CB1 affinity (K(i) = 11.7 nM) and the highest CB1 selectivity of the whole series (K(i)CB2/K(i)CB1 = 384.6). These new compounds appeared to be able to pass the blood brain barrier and to counteract the activity of cannabinoid agonist. According to the results of mice vas deferens assays, as in the case of rimonabant, derivatives 21a, 22a, and 22b showed inverse agonist activity. In contrast, as a preliminary result to be confirmed, compound 23a exhibited neutral antagonist profile. According to the data obtained through an acute animal model, selected compounds 21a, 22a, and 23a evidenced the capability to significantly reduce food intake. At specific conditions, the effect of the novel compounds were higher than that induced by rimonabant. Amongst the novel CB1 antagonist compounds, 23a may represent a useful candidate agent for the treatment of obesity and its metabolic complications, with reduced side effects relative to those instead observed with rimonabant.

The compound N-piperidinyl-[8-chloro-1-(2,4-dichlorophenyl)-1,4,5,6-tetrahydrobenzo [6,7]cyclohepta[1,2-c]pyrazole-3-carboxamide] (NESS 0327) was synthesized and evaluated for binding affinity toward cannabinoid CB1 and CB2 receptor. NESS 0327 exhibited a stronger selectivity for CB1 receptor compared with N-piperidinyl-5-(4-chlorophenyl)-1-(2,4-dichlorophenyl)-4-methyl-1H-pyrazole-3-carboxamide (SR 141716A), showing a much higher affinity for CB1 receptor (Ki = 350 +/- 5 fM and 1.8 +/- 0.075 nM, respectively) and a higher affinity for the CB2 receptor (Ki = 21 +/- 0.5 nM and 514 +/- 30 nM, respectively). Affinity ratios demonstrated that NESS 0327 was more than 60,000-fold selective for the CB1 receptor, whereas SR 141716A only 285-fold. NESS 0327 alone did not produce concentration-dependent stimulation of guanosine 5'-O-(3-[35S]thio)-triphosphate ([35S]GTPgammaS) binding in rat cerebella membranes. Conversely, NESS 0327 antagonized [R(+)-[2,3-dihydro-5-methyl-3-[(morpholinyl)methyl]pyrolol [1,2,3-de]-1,4-benzoxazin-yl]-(1-naphthalenyl)methanone mesylate] (WIN 55,212-2)-stimulated [35S]GTPgammaS binding. In functional assay, NESS 0327 antagonized the inhibitory effects of WIN 55,212-2 on electrically evoked contractions in mouse isolated vas deferens preparations with pA2 value of 12.46 +/- 0.23. In vivo studies indicated that NESS 0327 antagonized the antinociceptive effect produced by WIN 55,212-2 (2 mg/kg s.c.) in both tail-flick (ID50 = 0.042 +/- 0.01 mg/kg i.p.) and hot-plate test (ID50 = 0.018 +/- 0.006 mg/kg i.p.). These results indicated that NESS 0327 is a novel cannabinoid antagonist with high selectivity for the cannabinoid CB1 receptor.