The neuroprotective mechanism of 2-arachidonoylglycerol 2-AG against non-caspase-dependent apoptosis in mice hippocampal neurons following MCAO

2-Arachidonoylglycerol Activity in Over Ischemia Reperfusion Damage: Can Endocannabinoids Protect Ovarian Reserve?

Objective: The present study aimed to demonstrate the possible effects of increased 2-arachidonoylglycerol (2-AG) by applying the monoacylglycerol lipase inhibitor KML-29 on rats with ovarian ischemia-reperfusion (IR) model. Methods: Forty-eight female Wistar albino rats were divided into six groups. Group 1: Sham, Group 2: Ischemia, Group 3: IR, Group 4: IR + KML-29 (2 mg/kg), Group 5: IR + KML-29 (20 mg/kg), and Group 6: IR + vehicle (dimethyl sulfoxide). Three hours of ischemia followed by 3 h of reperfusion. Two different doses of KML-29 (2 and 10 mg/kg) were administered intraperitoneally in Groups 4 and 5, 30 min before reperfusion. Ovarian IR injury and ovarian reserve were evaluated histopathological and by using nuclear factor (NF)-κB, interleukin (IL)-1β, tumor necrosis factor (TNF)-α, transforming growth factor (TGF)-β1, superoxide dismutase, glutathione peroxidase pre-/postoperative blood antimullerian hormone, and inhibin B. Results: In the KML-1 and KML-2 groups, this damage was significantly reduced compared to the ischemia group. NF-κB, IL-1β, TNF-α, and TGF-β1 immunoreactivities increased statistically significantly in the ischemia group compared to the control group (p<0.001). Immunoreactivities of these proteins were significantly decreased in the KML-1 and KML-2 groups (p<0.001). It was observed that the number of these apoptotic cells decreased significantly in the KML-1 and KML-2 groups compared to the ischemia group (p<0.001). The postoperative inhibin level showed a significant decrease in the ischemia group compared to the sham group, while a significant increase was observed in the KML-1 and KML-2 groups compared to the ischemia group. Conclusion: It was seen that anti-inflammatory, antioxidant, and antiapoptotic activity was formed, and the ovarian reserve was preserved with 2-AG in ovarian IR damage. The protective effect of endocannabinoids on the ovaries may create a promising new treatment strategy for many pathologies that will affect the ovarian reserve.

Hormetic effects of a cannabinoid system component, 2-arachidonoyl glycerol, on cell viability and expression profile of growth factors in cultured mouse Sertoli cells: Friend or foe of male fertility?

The generally undesired effects of exocannabinoids on male reproduction include alterations in testicular cell proliferation and function, as well as apoptosis induction. However, this paradigm has been challenged by the ability of endocannabinoids to regulate reproductive function. The present study addresses these paradoxical facts by investigating the effects of the endocannabinoid 2-arachidonoyl glycerol (2-AG) on mouse Sertoli cells' survival and apoptosis, with a mechanistic insight into Sertoli cell-based growth factors' production. The Mus musculus Sertoli cell line (TM4) was exposed to different concentrations of 2-AG, and cell viability was evaluated using MTT assay. Growth factors' gene and protein expressions were analyzed through RT-PCR and western blotting. 2-AG concentration dependently increased TM4 viability, with a slight increase starting at 0.0001 µM, a peak of 190% of the control level at 1 µM, and a decrease at 3 µM. Moreover, 2-AG paradoxically altered mRNA expression of caspase-3 and growth factors. Caspase-3 mRNA expression was down-regulated, and growth factors mRNA and protein expression were up-regulated when using a low concentration of 2-AG (1 μM). Opposite effects were observed by a higher concentration of 2-AG (3 μM). These paradoxical effects of 2-AG can be explained through the concept of hormesis. The results indicate the pivotal role of 2-AG in mediating Sertoli cell viability and apoptosis, at least in part, through altering growth factors secretion. Furthermore, they suggest the involvement of endocannabinoids in Sertoli cell-based physiological and pathological conditions and reflect the ability of abnormally elevated 2-AG to mimic the actions of exocannabinoids in reproductive dysfunction.

The endocannabinoid 2-arachidonoylglycerol and dual ABHD6/MAGL enzyme inhibitors display neuroprotective and anti-inflammatory actions in the in vivo retinal model of AMPA excitotoxicity

The endocannabinoid system has been shown to be a putative therapeutic target for retinal disease. Here, we aimed to investigate the ability of the endocannabinoid 2-arachidonoylglycerol (2-AG) and novel inhibitors of its metabolic enzymes, α/β-hydrolase domain-containing 6 (ABHD6) and monoacylglycerol lipase (MAGL), a) to protect the retina against excitotoxicity and b) the mechanisms involved in the neuroprotection. Sprague-Dawley rats, wild type and Akt2^-/- C57BL/6 mice were intravitreally administered with phosphate-buffered saline or (RS)-α-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid hydrobromide (AMPA). 2-AG was intravitreally co-administered with AMPA in the absence and presence of AM251 or AM630 (cannabinoid 1 and 2 receptor antagonists, respectively) or Wortmannin [Phosphoinositide 3-Kinase (PI3K)/Akt inhibitor]. Inhibitors of ABHD6 and dual ABHD6/MAGL (AM12100 and AM11920, respectively) were co-administered with AMPA intravitreally in rats. Immunohistochemistry was performed using antibodies raised against retinal neuronal markers (bNOS), microglia (Iba1) and macroglia (GFAP). TUNEL assay and real-time PCR were also employed. The CB2 receptor was expressed in rat retina (approx. 62% of CB1 expression). 2-AG attenuated the AMPA-induced increase in TUNEL⁺ cells. 2-AG activation of both CB1 and CB2 receptors and the PI3K/Akt downstream signaling pathway, as substantiated by the use of Akt2^-/- mice, afforded neuroprotection against AMPA excitotoxicity. AM12100 and AM11920 attenuated the AMPA-induced glia activation and produced a dose-dependent partial neuroprotection, with the dual inhibitor AM11920 being more efficacious. These results show that 2-AG has the pharmacological profile of a putative therapeutic for retinal diseases characterized by neurodegeneration and neuroinflammation, when administered exogenously or by the inhibition of its metabolic enzymes.