“Uremia leads to a number of metabolic and hormonal disorders including defective carbohydrate metabolism.
Endocannabinoids exert their effect on insulin and glucagon secretion via activation of specific receptors named CB1 and CB2. For this reason and the absence of reports on location and immunoreactivity of CB1, CB2 receptors compared to immunoreactivity of insulin- and glucagon- secreting cells in experimental uremia, the author decided to investigate this issue.
The aim of the present study was the immunohistochemical localization and evaluation of cannabinoid receptors (CB1, CB2), insulin and glucagon in the pancreatic islets of uremic rats.
It was revealed the decreased immunoreactivity of the CB1 receptor and higher intensity of the immunohistochemical reaction against CB2 receptor as compared to the value in the control animals. Significantly higher immunoreactivity of glucagon-positive cells and weaker immunoreactivity of insulin-positive cells were observed in pancreatic islets of uremic rats.
The obtained results indicate the involvement of cannabinoid receptors in the pathomechanism of carbohydrate metabolism disorders, associated with abnormal secretion of hormones by the α and β cells in uremia.”
“Uremia is a clinical syndrome marked by elevated concentrations of urea in the blood and associated with fluid, electrolyte, and hormone imbalances and metabolic abnormalities, which develop in parallel with deterioration of renal function.The term uremia, which literally means urine in the blood, was first used by Piorry to describe the clinical condition associated with renal failure” https://emedicine.medscape.com/article/245296-overview
“Obesity, an important risk factor for developing chronic kidney disease (CKD), affects the kidneys by two main molecular signaling pathways: the endocannabinoid/CB1 R system, whose activation in obesity promotes renal inflammation, fibrosis, and injury; and the inducible nitric oxide synthase (iNOS), which generates reactive oxygen species resulting in oxidative stress. Hence, a combined peripheral inhibitory molecule that targets both CB1 R and iNOS may serve as an efficacious therapeutic agent against obesity-induced CKD.
Enhanced expression of CB1 R and iNOS in renal tubules was found in human kidney patients with obesity and other CKDs. The hybrid inhibitor ameliorated obesity-induced kidney morphological and functional changes via decreasing kidney inflammation, fibrosis, oxidative stress, and renal injury. Some of these features were independent of the improved metabolic profile mediated via inhibition of CB1 R. An additional interesting finding is that these beneficial effects on the kidney were partially associated with modulating renal adiponectin signaling.
CONCLUSIONS AND IMPLICATIONS:
Collectively, our results highlight the therapeutic relevance of blocking CB1 R and iNOS in ameliorating obesity-induced CKD.”
“Kidney ischemia reperfusion (IR) injury is an important health problem resulting in acute renal failure. After IR, the inflammatory and apoptotic process is triggered.
The relation of Cannabinoid type 2 (CB2) receptor with inflammatory and apoptotic process has been determined. The CB2 receptor has been shown to be localized in glomeruli and tubules in human and rat kidney. Activation of CB2 receptor with JWH-133 has been shown to reduce apoptosis and inflammation.
In this study, it was investigated whether CB2 activation with selective CB2 receptor agonist JWH-133 was protective against renal IR injury.
We found that JWH-133 and CB2 receptor activation had a curative effect against kidney IR damage. JWH-133 may be a new therapeutic agent in preventing kidney IR damage.”
“As the prevalence of kidney disease continues to rise worldwide, there is accumulating evidence that kidney injury and dysfunction, whether acute or chronic, is associated with major adverse outcomes, including mortality. Meanwhile, effective therapeutic options in the treatment of acute kidney injury (AKI) and chronic kidney disease (CKD) have been sparse.
Many of the effective treatments that are routinely utilized for different pathologies in patients without kidney disease have failed to demonstrate efficacy in those with renal dysfunction. Hence, there is an urgent need for discovery of novel pathways that can be targeted for innovative and effective clinical therapies in renal disease states.
There is now accumulating evidence that the endocannabinoid (EC) system plays a prominent role in normal renal homeostasis and function. In addition, numerous recent studies have described mechanisms through which alteration in the EC system can contribute to kidney damage and disease. These include a potential role for cannabinoid receptors in tubulo-glomerular damage and fibrosis, which are common features of AKI, interstitial nephritis, glomerulopathy, and other conditions leading to AKI and CKD.
These findings suggest that manipulating the EC system may be an effective therapeutic strategy for the treatment of kidney disease and injury. However, further mechanistic studies are needed to fully delineate the role of this system in various conditions affecting the kidneys. Furthermore, while most of the current literature is focused on the role of the EC system as a whole in renal pathophysiology, future studies will also need to clarify the contribution of each component of this system, including the EC mediators, in the pathogenesis of kidney disease and their potential role as part of a therapeutic strategy.”
“The use of marijuana in the USA has been steadily increasing over the last 10 years. This study is the first to investigate the effect of marijuana use by live kidney donors upon outcomes in both donors and recipients.
There was no difference in donor or recipient perioperative characteristics or postoperative outcomes based upon donor marijuana use (P > 0.05 for all comparisons). There was no difference in renal function between NMUD and MUD groups and no long-term difference in kidney allograft function between NMKR and MKR groups.
Considering individuals with a history of marijuana use for living kidney donation could increase the donor pool and yield acceptable outcomes.”
“There is no difference in renal function between MUD and NMUD groups following kidney donation. In addition, there is no difference between MKR and NMKR groups following transplant. If current trends persist into the future, then there will be a further increase in both recreational and medicinal marijuana use. For this reason, the growing population of marijuana users will become an even more significant segment of the potential living kidney donor pool. Subsequently, consideration of marijuana using kidney donors could increase the donor pool.”
“In this review, we discuss the role of the endocannabinoid (eCB) system in regulating energy and metabolic homeostasis. Endocannabinoids, via activating the cannabinoid type-1 receptor (CB1R), are commonly known as mediators of the thrifty phenotype hypothesis due to their activity in the central nervous system, which in turn regulates food intake and underlies the development of metabolic syndrome. Indeed, these findings led to the clinical testing of globally acting CB1R blockers for obesity and various metabolic complications. However, their therapeutic potential was halted due to centrally mediated adverse effects. Recent observations that highlighted the key role of the peripheral eCB system in metabolic regulation led to the preclinical development of various novel compounds that block CB1R only in peripheral organs with very limited brain penetration and without causing behavioral side effects. These unique molecules, which effectively ameliorate obesity, type II diabetes, fatty liver, insulin resistance, and chronic kidney disease in several animal models, are likely to be further developed in the clinic and may revive the therapeutic potential of blocking CB1R once again.”
“Diabetes mellitus is a complex, multifactorial disorder that is attributed to pancreatic β cell dysfunction. Pancreatic β cell dysfunction results in declining utilization of glucose by peripheral tissues as kidney and it leads to nephropathy. Excessive production and accumulation of free radicals and incapable antioxidant defense system lead to impaired redox status. Macromolecular damage may occur due to impaired redox status and also immune imbalance.
Δ9-Tetrahydrocannabinol (THC) is the main active ingredient in cannabis. THC acts as an immunomodulator and an antioxidant agent.
Our aim was to evaluate the effects of THC in the diabetic kidney.
According to our data, THC has ameliorative effects on the impaired redox status of diabetic kidney and also it acts as an immunomodulator. Therefore, THC might be used as a therapeutic agent for diabetic kidneys but its usage in the healthy kidney may show adverse effects.”
“Acute kidney injury (AKI) is an increasing problem clinically and is associated with chronic kidney disease progression.
Cannabinoid type 2 receptor activation has been shown to mitigate some of the deleterious tubular effects due to AKI, but its role on the renal vasculature has not been fully described.
In this study, we investigated the effects of our novel cannabinoid CB2 receptor agonist, SMM-295, on renal vasculature by assessing cortical perfusion using laser Doppler flowmetry and changes in luminal diameter using isolated afferent arterioles.
These data provide new insight into the potential benefit of SMM-295 by activating vascular and non-vascular CB2 receptors to promote renal vasodilation, and provide a new therapeutic target to treat renal injuries that impact renal blood flow dynamics.”
“Diabetic nephropathy (DN), a distinct manifestation of diabetic kidney disease, affects approximately 30% of patients with diabetes. While most attention has been focused on glomerular changes related to DN, there is growing evidence that tubulopathy is a key feature in the pathogenesis of this disease. The renal proximal tubule cells (RPTCs) are particularly sensitive to the deleterious effect of chronic hyperglycemia. However, the cellular changes that control the dysfunction of the RPTCs are not fully understood.
Controlling glucose reabsorption in the proximal tubules via inhibition of glucose transporters (GLUT) has emerged as a promising therapeutic in ameliorating DN.
Overactivation of the renal endocannabinoid (eCB) system via the cannabinoid-1 receptor (CB1R) contributes to the development of DN, and its blockade by globally acting or peripherally restricted CB1R antagonists has been shown to ameliorate renal dysfunction in different murine models for diabetes. Recently, we have utilized various pharmacological and genetic tools to show that the eCB/CB1R system contributes to the development of DN via regulating the expression, translocation, and activity of the facilitative GLUT2 located in the RPTCs.
These findings have the potential to be translated into therapy, and support the rationale for the preclinical development of novel renal-specific CB1R and/or GLUT2 inhibitors for the treatment of DN.”