“Chronic kidney disease (CKD) remains a major challenge for Public Health systems and corresponds to the replacement of renal functional tissue by extra-cellular matrix proteins such as collagens and fibronectin. There is no efficient treatment to date for CKD except nephroprotective strategies. The cannabinoid system and more specifically the cannabinoid receptors 1 (CB1) and 2 (CB2) may represent a new therapeutic target in CKD. Our review will first focus on the current state of knowledge regarding the cannabinoid system in normal renal physiology and in various experimental nephropathies, especially diabetes. We will review the data obtained in models of diabetes and obesity as well as in nonmetabolic models of renal fibrosis and emphasizes the promising role of CB1 blockers and CB2 agonists in the development of renal disease and fibrosis. Next, we will review the current state of knowledge regarding the cellular pathways involved in renal fibrogenesis and renal injury. Overall, this review will highlight the therapeutic potential of targeting the cannabinoid receptors in CKD and diabetes.” https://www.ncbi.nlm.nih.gov/pubmed/28901271]]>
Category Archives: Endocannabinoid System
Polymorphism rs3123554 in the cannabinoid receptor gene type 2 (CNR2) reveals effects on body weight and insulin resistance in obese subjects.
“Few studies assessing the relationship between single nucleotide polymorphisms in CNR2 and obesity or its related metabolic parameters are available.
OBJECTIVE:
To investigate the influence of polymorphism rs3123554 in the CNR2 receptor gene on obesity anthropometric parameters, insulin resistance, and adipokines in subjects with obesity.DESIGN:
The study population consisted of 1027 obese subjects, who were performed bioelectrical impedance analyses, blood pressure measurements, serial assessments of dietary intake during three days, and biochemical tests.RESULTS:
Genotypes GG, GA, and AA were found in 339 (33.0%), 467 (45.5%), and 221 (21.5%) respectively. Body mass index, weight, fat mass, waist circumference, insulin, HOMA-IR, and triglyceride and leptin levels were higher in A-allele carriers as compared to non A-allele carriers. No differences were seen in these parameters between the GA and AA genotypes. There were no statistical differences in dietary intake.CONCLUSION:
The main study finding was the association of the minor allele of the SNP rs3123554 in the CNR2 gene with body weight and triglyceride, HOMA-IR, insulin, and leptin levels.” https://www.ncbi.nlm.nih.gov/pubmed/28895540 http://www.sciencedirect.com/science/article/pii/S2530016417301799?via%3Dihub]]>The FAAH inhibitor URB597 suppresses hippocampal maximal dentate afterdischarges and restores seizure-induced impairment of short and long-term synaptic plasticity.
“Synthetic cannabinoids and phytocannabinoids have been shown to suppress seizures both in humans and experimental models of epilepsy. However, they generally have a detrimental effect on memory and memory-related processes. Here we compared the effect of the inhibition of the endocannabinoid (eCB) degradation versus synthetic CB agonist on limbic seizures induced by maximal dentate activation (MDA) acute kindling. Moreover, we investigated the dentate gyrus (DG) granule cell reactivity and synaptic plasticity in naïve and in MDA-kindled anaesthetised rats. We found that both the fatty acid amide hydrolase (FAAH) inhibitor URB597 and the synthetic cannabinoid agonist WIN55,212-2 displayed AM251-sensitive anti-seizure effects. WIN55,212-2, dose-dependently (0.5-2 mg/kg, i.p.) impaired short-term plasticity (STP) and long-term potentiation (LTP) at perforant path-DG synapses in naïve rats. Strikingly, URB597 (1 mg/kg, i.p.) was devoid of any deleterious effects in normal conditions, while it prevented seizure-induced alterations of both STP and LTP. Our evidence indicates that boosting the eCB tone rather than general CB1 activation might represent a potential strategy for the development of a new class of drugs for treatment of both seizures and comorbid memory impairments associated with epilepsy.” https://www.ncbi.nlm.nih.gov/pubmed/28894217 https://www.nature.com/articles/s41598-017-11606-1]]>
Activation of dorsal horn cannabinoid CB2 receptor suppresses the expression of P2Y12 and P2Y13 receptors in neuropathic pain rats.
“More evidence suggests that dorsal spinal cord microglia is an important site contributing to CB2 receptor-mediated analgesia. The upregulation of P2Y12 and P2Y13 purinoceptors in spinal dorsal horn microglia is involved in the development of pain behavior caused by peripheral nerve injury. However, it is not known whether the expression of P2Y12 and P2Y13 receptors at spinal dorsal horn will be influenced after CB2 receptor activation in neuropathic pain rats. Chronic constriction injury (CCI) and intrathecal ADPbetaS injection were performed in rats to induce neuropathic pain.
In CCI- and ADPbetaS-treated rats, AM1241 pretreatment could efficiently activate CB2 receptor, while inhibiting p38MAPK and NF-kappaB activation in the dorsal spinal cord. CB2 receptor stimulation decreased P2Y13 receptor expression via p38MAPK/NF-kappaB signaling. On the other hand, CB2 receptor activation decreased P2Y12 receptor expression via p38MAPK-independent NF-kappaB signaling pathway.”
https://www.ncbi.nlm.nih.gov/pubmed/28899427
Effects of coadministration of low dose cannabinoid type 2 receptor agonist and morphine on vanilloid receptor 1 expression in a rat model of cancer pain.
“Morphine is widely used as an analgesic to treat moderate to severe pain, but chronic morphine use is associated with development of tolerance and dependence, which limits its analgesic efficacy. Our previous research has showed that nonanalgetic dose of a cannabinoid type 2 (CB2) receptor agonist reduced morphine tolerance in cancer pain. A previous study showed the colocalization of CB2 and transient receptor potential vanilloid 1 (TRPV1) in human and rat dorsal root ganglia (DRG) sensory neurons. Whether coadministration of a CB2 receptor agonist and morphine could reduce TRPV1 expression in morphine‑induced antinociception and tolerance in cancer pain is unclear. Therefore, we investigated the effects of coadministration of a CB2 receptor agonist AM1241 and morphine on TRPV1 expression and tolerance in cancer pain. Coadministration of AM1241 and morphine for 8 days significantly reduced morphine tolerance, as assessed by measuring paw withdrawal latency to a radiant heat stimulation, in Walker 256 tumor‑bearing rats. Repeated morphine treatment for a period of 8 days induced upregulation of the TRPV1 protein expression levels in the DRG in the tumor‑bearing rats, although no change in mRNA expression. Pretreatment with AM1241 reduced this morphine‑induced upregulation of TRPV1 and the effect was reversed by the CB2 receptor antagonist AM630. Our findings suggest that coadministration of a CB2 receptor agonist AM1241 and morphine reduced morphine tolerance possibly through regulation of TRPV1 protein expression in the DRG in cancer pain.”
https://www.ncbi.nlm.nih.gov/pubmed/28901432
https://www.spandidos-publications.com/10.3892/mmr.2017.7479
Tingenone, a pentacyclic triterpene, induces peripheral antinociception due to cannabinoid receptors activation in mice.
“Several works have shown that triterpenes induce peripheral antinociception by activation of cannabinoid receptors and endocannabinoids; besides, several research groups have reported activation of cannabinoid receptors in peripheral antinociception.
The aim of this study was to assess the involvement of the cannabinoid system in the antinociceptive effect induced by tingenone against hyperalgesia evoked by prostaglandin E2 (PGE2) at peripheral level.
The results suggest that tingenone induced a peripheral antinociceptive effect via cannabinoidreceptor activation. Therefore, this study suggests a pharmacological potential for a new analgesic drug.”
https://www.ncbi.nlm.nih.gov/pubmed/28889355
“Autism spectrum disorder (ASD) defines a group of neurodevelopmental disorders whose symptoms include impaired communication and social interaction with restricted or repetitive motor movements, frequently associated with general cognitive deficits. Although it is among the most severe chronic childhood disorders in terms of prevalence, morbidity, and impact to the society, no effective treatment for ASD is yet available, possibly because its neurobiological basis is not clearly understood hence specific drugs have not yet been developed. The endocannabinoid (EC) system represents a major neuromodulatory system involved in the regulation of emotional responses, behavioral reactivity to context, and social interaction. Furthermore, the EC system is also affected in conditions often present in subsets of patients diagnosed with ASD, such as seizures, anxiety, intellectual disabilities, and sleep pattern disturbances. Despite the indirect evidence suggestive of an involvement of the EC system in ASD, only a few studies have specifically addressed the role of the EC system in the context of ASD. This review describes the available data on the investigation of the presence of alterations of the EC system as well as the effects of its pharmacological manipulations in animal models of ASD-like behaviors.”
“The