Endocannabinoid System in Hepatic Glucose Metabolism, Fatty Liver Disease, and Cirrhosis.

ijms-logo

“There is growing evidence that glucose metabolism in the liver is in part under the control of the endocannabinoid system (ECS) which is also supported by its presence in this organ. The ECS consists of its cannabinoid receptors (CBRs) and enzymes that are responsible for endocannabinoid production and metabolism. ECS is known to be differentially influenced by the hepatic glucose metabolism and insulin resistance, e.g., cannabinoid receptor type 1(CB1) antagonist can improve the glucose tolerance and insulin resistance. Interestingly, our own study shows that expression patterns of CBRs are influenced by the light/dark cycle, which is of significant physiological and clinical interest. The ECS system is highly upregulated during chronic liver disease and a growing number of studies suggest a mechanistic and therapeutic impact of ECS on the development of liver fibrosis, especially putting its receptors into focus. An opposing effect of the CBRs was exerted via the CB1 or CB2 receptor stimulation. An activation of CB1promoted fibrogenesis, while CB2 activation improved antifibrogenic responses. However, underlying mechanisms are not yet clear. In the context of liver diseases, the ECS is considered as a possible mediator, which seems to be involved in the synthesis of fibrotic tissue, increase of intrahepatic vascular resistance and subsequently development of portal hypertension. Portal hypertension is the main event that leads to complications of the disease. The main complication is the development of variceal bleeding and ascites, which have prognostic relevance for the patients. The present review summarizes the current understanding and impact of the ECS on glucose metabolism in the liver, in association with the development of liver cirrhosis and hemodynamics in cirrhosis and its complication, to give perspectives for development of new therapeutic strategies.”

https://www.ncbi.nlm.nih.gov/pubmed/31121839

https://www.mdpi.com/1422-0067/20/10/2516

Facebook Twitter Pinterest Stumbleupon Tumblr Posterous

AM-1241 CB2 Receptor Agonist Attenuates Inflammation, Apoptosis and Stimulate Progenitor Cells in Bile Duct Ligated Rats.

 “The cannabinoid receptor 2 (CB2) plays a pleiotropic role in the innate immunity and is considered a crucial mediator of liver disease.

Cannabinoid CB2 receptor activation has been reported to attenuate liver fibrosis in CCl4 exposed mice and also plays a potential role in liver regeneration in a mouse model of I/R and protection against alcohol-induced liver injury.

AIM:

In this study, we investigated the impact of CB2 receptors on the antifibrotic and regenerative process associated with cholestatic liver injury.

RESULTS:

Following bile duct ligation (BDL) for 3 weeks, there was increased aminotransferase levels, marked inflammatory infiltration and hepatocyte apoptosis with induced oxidative stress, as reflected by increased lipid peroxidation. Conversely, following treatment with the CB2 agonist, AM-1241, BDL rats displayed a reduction in liver injury and attenuation of fibrosis as reflected by expression of hydroxyproline and α-smooth muscle actin. AM1241 treatment also significantly attenuated lipid peroxidation end-products, p53-dependent apoptosis and also attenuated inflammatory process by stimulating IL-10 production. Moreover, AM1241 treated rats were associated with significant expression of hepatic progenitor/oval cell markers.

CONCLUSION:

In conclusion, this study points out that CB2 receptors reduce liver injury and promote liver regeneration via distinct mechanisms including IL-10 dependent inhibition of inflammation, reduction of p53-reliant apoptosis and through stimulation of oval/progenitor cells. These results suggest that CB2 agonists display potent hepatoregenrative properties, in addition to their antifibrogenic effects.”

https://www.ncbi.nlm.nih.gov/pubmed/30976335

https://www.id-press.eu/mjms/article/view/oamjms.2019.194

Facebook Twitter Pinterest Stumbleupon Tumblr Posterous

The Role of Cannabinoids in the Setting of Cirrhosis.

medicines-logo

“Although the mortality rates of cirrhosis are underestimated, its socioeconomic burden has demonstrated a significant global impact. Cirrhosis is defined by the disruption of normal liver architecture after years of chronic insult by different etiologies. Treatment modalities are recommended primarily in decompensated cirrhosis and specifically tailored to the different manifestations of hepatic decompensation. Antifibrogenic therapies are within an active area of investigation.

The endocannabinoid system has been shown to play a role in liver disease, and cirrhosis specifically, with intriguing possible therapeutic benefits. The endocannabinoid system comprises cannabinoid receptors 1 (CB1) and cannabinoid receptor 2 (CB2) and their ligands, endocannabinoids and exocannabinoids.

CB1 activation enhances fibrogenesis, whereas CB2 activation counteracts progression to fibrosis. Conversely, deletion of CB1 is associated with an improvement of hepatic fibrosis and steatosis, and deletion of CB2 results in increased collagen deposition, steatosis, and enhanced inflammation.

CB1 antagonism has also demonstrated vascular effects in patients with cirrhosis, causing an increase in arterial pressure and vascular resistance as well as a decrease in mesenteric blood flow and portal pressure, thereby preventing ascites. In mice with hepatic encephalopathy, CB1 blockade and activation of CB2 demonstrated improved neurologic score and cognitive function.

Endocannabinoids, themselves also have mechanistic roles in cirrhosis. Arachidonoyl ethanolamide (AEA) exhibits antifibrogenic properties by inhibition of HSC proliferation and induction of necrotic death. AEA induces mesenteric vasodilation and hypotension via CB1 induction. 2-arachidonoyl glycerol (2-AG) is a fibrogenic mediator independent of CB receptors, but in higher doses induces apoptosis of HSCs, which may actually show antifibrotic properties. 2-AG has also demonstrated growth-inhibitory and cytotoxic effects.

The exocannabinoid, THC, suppresses proliferation of hepatic myofibroblasts and stellate cells and induces apoptosis, which may reveal antifibrotic and hepatoprotective mechanisms. Thus, several components of the endocannabinoid system have therapeutic potential in cirrhosis.”

https://www.ncbi.nlm.nih.gov/pubmed/29890719

http://www.mdpi.com/2305-6320/5/2/52

Facebook Twitter Pinterest Stumbleupon Tumblr Posterous

Cannabinoid signaling and liver therapeutics.

Journal of Hepatology Home

“Over the last decade, the endocannabinoid system has emerged as a pivotal mediator of acute and chronic liver injury, with the description of the role of CB1 and CB2 receptors and their endogenous lipidic ligands in various aspects of liver pathophysiology.

A large number of studies have demonstrated that CB1 receptor antagonists represent an important therapeutic target, owing to beneficial effects on lipid metabolism and in light of its antifibrogenic properties.

Unfortunately, the brain-penetrant CB1 antagonist rimonabant, initially approved for the management of overweight and related cardiometabolic risks, was withdrawn because of an alarming rate of mood adverse effects.

However, the efficacy of peripherally-restricted CB1 antagonists with limited brain penetrance has now been validated in preclinical models of NAFLD, and beneficial effects on fibrosis and its complications are anticipated.

CB2 receptor is currently considered as a promising anti-inflammatory and antifibrogenic target, although clinical development of CB2 agonists is still awaited.

In this review, we highlight the latest advances on the impact of the endocannabinoid system on the key steps of chronic liver disease progression and discuss the therapeutic potential of molecules targeting cannabinoid receptors…

Overwhelming evidence supports the therapeutic potential of peripherally-restricted CB1 antagonists and CB2 agonists in the management of chronic liver diseases.”

http://www.journal-of-hepatology.eu/article/S0168-8278(13)00212-2/fulltext

http://www.thctotalhealthcare.com/category/liver-disease/

Facebook Twitter Pinterest Stumbleupon Tumblr Posterous

Beneficial paracrine effects of cannabinoid receptor 2 on liver injury and regeneration.

Logo of hal

“Accumulating data indicate that the cannabinoid system is a crucial mediator in the pathogenesis of a variety of liver diseases.

In the present study we show that CB2 receptors reduce liver injury and accelerate liver regeneration via distinct pathways.

CB2 receptors reduce liver injury and promote liver regeneration following acute insult, via distinct paracrine mechanisms involving hepatic myofibroblasts.

These results suggest that CB2 agonists display potent hepatoprotective properties, in addition to their antifibrogenic effects.”

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3246453/
“Association of the cannabinoid receptor 2 (CB2) Gln63Arg polymorphism with indices of liver damage in obese children: an alternative way to highlight the CB2 hepatoprotective properties.” http://www.ncbi.nlm.nih.gov/pubmed/21608006

http://www.thctotalhealthcare.com/category/liver-disease/

Facebook Twitter Pinterest Stumbleupon Tumblr Posterous