Melatonin shown to protect kidney damage caused by obesity with diabetes

In continuation of my update on Melatonin

Scientists from the University of Granada (UGR), the Hospital Universitario La Paz (Madrid), and the University of Texas (U.S.) have taken an important step in the fight against kidney damage and its progression toward kidney failure, which is closely related to diabesity (obesity with type 2 diabetes) and its complications.

Specifically, in two new studies recently published in the Journal of Clinical Medicine and Pharmaceuticals, researchers have developed an obese and diabetic rodent model and have shown that melatonin protects from kidney damage caused by diabesity.

The scientists have shown that chronic administration of melatonin at doses (10 mg/kg body weight/day) prevents mitochondrial and endoplasmic reticulum disruption, which play a critical role in the development and pathogenesis of kidney cell (nephron) damage, and its progression to renal failure.

Thus, it has been shown that melatonin prevents the impairment of the function and dynamics of cellular mitochondria, decreasing the increased production of oxygen free radicals (responsible for oxidative stress). It also prevents pathological alteration in the function of the endoplasmic reticulum (another cell cytoplasmic organelle), which, in conditions of abnormally high oxidative stress, is related to an increase in programmed cell death (of the nephron) leading to the loss of renal functionality, as a preliminary step to the development of renal failure and the need for hemodialysis or transplantation.

The studies coordinated by the UGR show the efficacy of melatonin in halting the progression of renal damage mediated by mitochondrial damage and excess endoplasmic reticulum stress.

As the lead author of this study, Ahmad Agil, a researcher at the Department of Pharmacology of the UGR, says, "Kidney damage is caused by metabolic complications of obesity, such as diabetes, hypertension, blood lipid disorders or fatty liver disease. Given that the prevalence of these pathologies (collectively recognized as metabolic syndrome) continues to increase, kidney damage and its progression over time to kidney failure has become a health problem that affects millions of people worldwide, with a great socioeconomic cost, requiring hemodialysis facilities and/or kidney transplant services, with the corresponding compatibility studies required."

The importance of the work lies not only in the efficacy of melatonin in counteracting the two proposed mechanisms of renal damage (based on the alteration of mitochondrial function and dynamics and the function of the endoplasmic reticulum (ER)), but they also propose an alternative preventive treatment that would improve this renal function with a well-studied drug with a very high safety profile such as melatonin, which is a drug that in the EU must be prescribed by a doctor and is already administered in the treatment of insomnia.

The new findings have also been associated with an improvement in glomerular filtration rate and renal damage of the nephron, manifested in a decrease in creatinine clearance levels (the best marker of renal function), proteinuria, and in the improvement of renal structure, observed after histopathological study of the kidney.

These results are in line with those previously published by these researchers in the last 10 years, demonstrating that the pharmacological administration of melatonin constitutes another new strategy in the therapeutic approach to diabesity (central obesity and its type 2 diabetes) and its complications (such as hepatic steatosis, hypertension, lipid alteration, etc.).

"Our main challenge is the application of melatonin and other strategies such as intermittent fasting in the field of medicine, especially to address the possibility of a treatment perspective for the aforementioned pathologies (diabesity and its complications) that involve an increase in oxidative stress, and mitochondrial damage and associated meta-inflammation (inflammation of metabolic origin)," Agil says.

According to the results, melatonin could help treat kidney damage, which establishes the need to develop new clinical trials to test its effectiveness in humans. The next step is to investigate how it helps in the maintenance of mitochondrial and endoplasmic reticulum homeostasis, and to a greater extent, if melatonin therapy would allow delaying or stopping progressive renal damage by promoting its chronic pharmacological use in kidney repair and regeneration.

https://en.wikipedia.org/wiki/Melatonin

Melatonin shown to protect kidney damage caused by obesity with diabetes

Melatonin appears to suppress growth of breast cancer stem cells

In continuation of my update on Melatonin

Melatonin, a hormone produced in the human brain, appears to suppress the growth of breast cancer tumors.

Researchers at Michigan State University published this finding in the current issue ofGenes and Cancer. While treatments based on this key discovery are still years away, the results give scientists a key foundation on which to build future research.

"You can watch bears in the zoo, but you only understand bear behavior by seeing them in the wild," said David Arnosti, MSU biochemistry professor, director of MSU's Gene Expression in Development and Disease Initiative and co-author of the study. "Similarly, understanding the expression of genes in their natural environment reveals how they interact in disease settings. That's what is so special about this work."

The brain manufactures melatonin only at night to regulate sleep cycles. Epidemiologists and experimentalists have speculated that the lack of melatonin, due in part to our sleep-deprived modern society, put women at higher risk for breast cancer. The latest MSU study showed that melatonin suppresses the growth of breast cancer stem cells, providing scientific proof to support the growing body of anecdotal evidence on sleep deprivation.

The research team was led by Juliana Lopes, a visiting researcher from Sao Paolo, Brazil. Before the team could test its theory, the scientists had to grow tumors from stem cells, known as "mammospheres," a method perfected in the laboratory of James Trosko at MSU.

The growth of these mammospheres was enhanced with chemicals known to fuel tumor growth, namely, the natural hormone estrogen, and estrogen-like chemical Bisphenol A, or BPA, found in many types of plastic food packages.

Melatonin treatment significantly decreased the number and size of mammospheres when compared with the control group. Furthermore, when the cells were stimulated by estrogen or BPA and treated with melatonin at the same time, there was a greater reduction in the number and size of mammospheres.

"This work establishes the principal by which cancer stem cell growth may be regulated by natural hormones, and provides an important new technique to screen chemicals for cancer-promoting effects, as well as identify potential new drugs for use in the clinic," Trosko said.

Melatonin appears to suppress growth of breast cancer stem cells

In continuation of my update on Melatonin

Melatonin, a hormone produced in the human brain, appears to suppress the growth of breast cancer tumors.

Researchers at Michigan State University published this finding in the current issue ofGenes and Cancer. While treatments based on this key discovery are still years away, the results give scientists a key foundation on which to build future research.

"You can watch bears in the zoo, but you only understand bear behavior by seeing them in the wild," said David Arnosti, MSU biochemistry professor, director of MSU's Gene Expression in Development and Disease Initiative and co-author of the study. "Similarly, understanding the expression of genes in their natural environment reveals how they interact in disease settings. That's what is so special about this work."

The brain manufactures melatonin only at night to regulate sleep cycles. Epidemiologists and experimentalists have speculated that the lack of melatonin, due in part to our sleep-deprived modern society, put women at higher risk for breast cancer. The latest MSU study showed that melatonin suppresses the growth of breast cancer stem cells, providing scientific proof to support the growing body of anecdotal evidence on sleep deprivation.

The research team was led by Juliana Lopes, a visiting researcher from Sao Paolo, Brazil. Before the team could test its theory, the scientists had to grow tumors from stem cells, known as "mammospheres," a method perfected in the laboratory of James Trosko at MSU.

The growth of these mammospheres was enhanced with chemicals known to fuel tumor growth, namely, the natural hormone estrogen, and estrogen-like chemical Bisphenol A, or BPA, found in many types of plastic food packages.

Melatonin treatment significantly decreased the number and size of mammospheres when compared with the control group. Furthermore, when the cells were stimulated by estrogen or BPA and treated with melatonin at the same time, there was a greater reduction in the number and size of mammospheres.

"This work establishes the principal by which cancer stem cell growth may be regulated by natural hormones, and provides an important new technique to screen chemicals for cancer-promoting effects, as well as identify potential new drugs for use in the clinic," Trosko said.

Melatonin shows potential to slow tumor growth in certain breast cancers

An  early stage study shows melatonin   a hormone that regulates the body's sleep and awake cycles  may have the potential to help slow the growth of certain breast cancer tumors, according to researchers from Henry Ford Hospital in Detroit and Foundation for Research Support of the State of São Paulo.

Melatonin shows potential to slow tumor growth in certain breast cancers  

Reduced melatonin levels linked to greater diabetes risk - Life Extension Update

In continuation of my update on Melatonin....

"Melatonin receptors have been found throughout the body in many tissues including pancreatic islet cells, reflecting the widespread effects of melatonin on physiological functions such as energy metabolism and the regulation of body weight," Ciaran McMullan and colleagues at Brigham and Women's Hospital noted in their introduction to the article. "Loss-of-function mutations in the melatonin receptor are associated with insulin resistance and type 2 diabetes. Additionally, in a cross-sectional analysis of persons without diabetes, lower nocturnal melatonin secretion was associated with increased insulin resistance."

The researchers matched 370 women who developed diabetes while enrolled in the Nurses' Health Study with 370 nondiabetic participants. Morning urine samples obtained upon enrollment in 2000 were analyzed for the ratio of 6-sulfoxymelatonin (the major metabolite of melatonin) to creatinine in order to estimate overnight melatonin secretion.

Women with diabetes had a 6-sulfatoxymelatonin to creatinine ratio that was significantly lower than that of the control group. Among those whose ratio was among the lowest of the participants, the adjusted risk of developing diabetes was more than twice that of women whose ratio was among the highest group.

"This is the first time that an independent association has been established between nocturnal melatonin secretion and type 2 diabetes risk," announced Dr McMullan, who is a researcher in the Renal Division and Kidney Clinical Research Institute at BWH. "Hopefully this study will prompt future research to examine what influences a person's melatonin secretion and what is melatonin's role in altering a person's glucose metabolism and risk of diabetes."

"It is interesting to postulate from these data, in combination with prior literature, whether there is a causal role for reduced melatonin secretion in diabetes risk," the authors remark. "Further studies are needed to determine whether increasing melatonin levels (endogenously via prolonged nighttime dark exposure or exogenously via supplementation) can increase insulin sensitivity and decrease the incidence of type 2 diabetes."

Ref : http://jama.jamanetwork.com/article.aspx?articleid=1674239

Reduced melatonin levels linked to greater diabetes risk - Life Extension Update