Tag Archives: Hormone

The study explains how to rebuild the neurons inside fat to increase the calorie burning capacity | Instant News


A previous study suggested that you can lose weight, eat less or move more. However, despite studying it for many decades, the biology underlying this equation remains mysterious.

What really ignites the breakdown of fat molecules nerves embedded in fat, and new research now suggests that these fat burning of neurons previously unrecognized powers. If they get the right signal, they have the amazing ability to grow. This signal is the hormone leptin, which is secreted by fat cells.

In experiments with mice, the results of which are published in the journal Nature, the researchers found that, as a rule, a dense network of nerve fibers in adipose tissue is reduced in the absence of leptin and increases the hormone as a drug. These changes were shown to influence the ability of animals to burn energy stored in fat.

“While the architecture of the nervous system can significantly change how a young animal develops, we did not expect to find in this deep level of neural plasticity in an adult,” says Jeffrey M. Friedman, molecular geneticist of the Rockefeller University.

If confirmed in humans, this information can advance research on obesity and related diseases, and potentially opens the way for the development of new therapies, which target neurons in the adipose tissue.

The team began looking at what happens to mice that do not produce leptin on their own, and how they react when you speak with him.

Found in Friedman’s laboratory in 1994, the hormone relay signals from adipose tissue and the brain, allowing the nervous system to curb appetite and increase energy expenditure to control body weight. When mice are genetically engineered to stop the production of leptin, they grow three times heavier than a normal mouse. They eat more, move less, and can survive in what should be tolerated the cold because their body cannot properly use fat to generate heat.

Giving these mice leptin doses, however, and they quickly begin to eat less and move more. But when the researchers processed them longer, within two weeks, more profound changes have occurred: the animals began to break down white fat, which stores unused calories at a normal level and regained the ability to use another form of fat, brown fat, to produce heat.

It was slower than the changes that interested the research team, including first authors on the nature paper, Putianqi Wang, a graduate student in the lab, and Ken H. Luo, postdoctoral fellow. They suspect that changes of neurons outside of the brain-those that are distributed in fat … might explain why this part of the response to leptin it took some time.

Using the imaging technique, developed in the laboratories of the Rockefeller and Paul Cohen to visualize the nerves inside the body fat, researchers have traced the influence of leptin on fat-built-in neurons of the brain the hypothalamus region. Hence, they are found contributing to the growth of Leptin that message goes through the spinal cord back to the neurons to fat.

“This work is the first example of how leptin can regulate the presence of neurons in adipose tissue, white and brown,” added Cohen.

In this way, fat seems to be telling the brain how much nerve supply it needs to function properly. “Fat is indirectly controlled by its own innervation and hence function,” says Friedman. “It is an exquisite feedback loop”.

Future research will analyze the role of this pathway in human obesity and may provide a new approach to therapy. Most of the obese people produce high levels of leptin and showed a decrease of response to hormone injection, suggesting that their brains are resistant to the hormone. Thus, the bypass resistance leptin may have a therapeutic effect for these patients.

“In the new study, we see that similar to animals lacking leptin, obese leptin-resistant animals also show a low-fat innervation. Therefore, we assume that directly stimulating the nerves that Innervate fat and restoring the normal ability to use stored fat can create new opportunities for the treatment of obesity,” said Friedman.

.



image source

Research finds that specific brain cells trigger sugar consumption and cravings | Instant News


New research has identified specific brain cells that control how much sugar you eat and how hungry you are for sweet foods.

Most people enjoy sweets from time to time. However, unchecked “sweets” can lead to excessive consumption of sugary foods and chronic health problems such as obesity and type 2 diabetes. Understanding the biological mechanisms that control sugar intake and preference for sweetness may have important implications for controlling and preventing these health problems.

The new research is led by Dr. Matthew Potthoff, associate professor of neuroscience and pharmacology at Carver University in Iowa, and Dr. Matthew Gillum at Copenhagen University in Denmark. The research focuses on the action of a hormone called fibroblast growth. Factor 21 (FGF21). This hormone is known to play a role in energy balance, weight control and insulin sensitivity.

This is the first study to truly identify where this hormone works in the brain, and provides very cool insights into how to regulate sugar intake. “

Matthew Potthoff, a member of the Eagle Diabetes Brotherhood Research Center at UI and the Iowa Neuroscience Institute

Potthoff and his colleagues previously discovered that FGF21 is made in the liver in response to elevated sugar levels and plays a role in the brain to suppress sugar intake and preference for sweetness.

Based on this discovery, the team now shows for the first time which brain cells respond to FGF21 signaling and how this interaction helps regulate sugar intake and sweetness preferences. The study was published in the journal Cell metabolism, Also revealed how hormones mediate their effects.

Although FGF21 is known to function in the brain, because hormone receptors are expressed at very low levels, it is difficult to “see”, so determining the exact cellular target becomes complicated. Using various techniques, the researchers were able to accurately identify which cells express the FGF21 receptor. By studying these cells, studies have shown that FGF21 targets glutamatergic neurons in the brain to reduce sugar intake and sweet taste preference. The researchers also showed that the effect of FGF21 on specific neurons in the hypothalamus of the peritoneum reduces sugar intake by enhancing the sensitivity of neurons to glucose.

Several drugs based on modified forms of FGF21 have been tested as treatments for obesity and diabetes. The new discovery may cause the new drug to more precisely target the different behaviors controlled by FGF21, which may help control how much sugar a person eats.

Resources:

Journal reference:

Jensen-Cody, so, Wait. (2020) FGF21 signaling to the hypothalamus glutamatergic neurons in the hypothalamus inhibits carbohydrate intake. Cell metabolism. doi.org/10.1016/j.cmet.2020.06.008.

.



image source

‘Owl’ Teens more likely to develop asthma and allergies | Instant News


Adolescents who prefer late night and sleep late the next day, are more likely to develop asthma and allergies than their early-bird counterparts, according to new research published today.

Compared to this morning, like those who go to bed later, around three times higher risk of developing asthma. We also found symptoms of allergic rhinitis, were twice as likely at the end of the sleepers and those who sleep early in the night.”

Subhabrata Moitra, senior researcher, postgraduate student with the respiratory center of Alberta in the Department of pulmonary medicine, University of Alberta

Moitra said over 300 million people suffer from asthma worldwide and the most common noncommunicable disease among children, and the number is growing every year. This is the first study to examine the “chronotype” or sleep time preferences and associations with asthma and Allergy in adolescents.

The researchers interviewed 1,684 adolescents in the Indian state of West Bengal, about their sleep preferences and health of the respiratory system, as part of the prevalence and risk factors of asthma and allergic diseases among adolescents (indicators) of the study. Questions included whether they had been diagnosed with asthma or have experienced symptoms of rhinitis, such as wheezing, runny nose or cough.

One of those who gets up late, and 23.6 percent reported having asthma, compared to 6.2 percent of early birds.

The researchers found a link between asthma and sleep preferences of the film will be teenagers, male or female, was a home, lived in rural or urban areas had parents with asthma or allergies, or were exposed to second-hand smoke.

Moitra said that people are naturally early risers.

“Our ancestors evolved to Wake up as the sun rose and go to bed as the sun,” he said.

“However, the preference for night-time seems inevitable for the younger generation, because digital screens are available at any time.”

Moitra said the researchers suspect that Teens who go to bed late at night when sleep deprivation or interruption of sleep. He said the blue or white tint of the light from the computer, television and smartphone screens disrupts the production and function of melatonin, the sleep hormone.

“The perfect sleep is the result of a good melatonin cycles,” said he, adding that melatonin can also affect the immune system and the development of asthma and allergies it is known that as a result of changes in the immune system.

Moitra said his team intends to conduct further research to explore this Association, including more objective tests of sleep quality and pulmonary function.

At the same time, it encourages doctors to ask patients more behavioral issues in the diagnosis of Allergy and asthma.

“We need to be more vigilant, to ask about eating habits, sleep, can they play outside, because this behavior can be changed to help get rid of the symptoms,” he suggested.

Said Moitra melatonin supplements can help with insomnia, but should not be taken regularly because they can disturb the natural production in the body hormone.

He also suggested that we should minimise the effect at night with artificial light, and when this is unavoidable, use Amber house lighting and led screens and to reduce the brightness.

The study was partially funded and the research center for Allergy asthma in Kolkata, India.

.



image source

Researchers discover “biologically appropriate” level of AMH in samples of human hair | Instant News


The prospect of a non-invasive test of ovarian reserve is a little closer following the results of a study showing that measurement of hormone fertility can be accurately taken from a sample of human hair.

Antimullerian hormone or AMH – became a key marker to assess how women respond to infertility treatment.

Hormone small cells surrounding each egg as it develops in the ovary and, thus, is seen as an indicator of ovarian reserve.

Although studies do not correlate AMH levels for a reliable chance of a live birth (or to predict the time of menopause), AMH measurement has become an essential marker in the assessment of how the patient will respond to ovarian stimulation for IVF – as a regular responder, poor responder (with eggs) or defendant (a lot of eggs and risk of ovarian hyperstimulation ovarian hyperstimulation syndrome). (1)

AMG is now measured in the serum taken from a blood sample intravenously. The readings represent a measure for a short time and is relatively invasive to complete.

Now, however, a new study presented in the online annual meeting ESHRE experienced determine the level of AMH from human hair and found that it is less invasive and “more appropriate representation of hormones” than the “sharp” source as whey.

The results are presented this week in the graduate student poster matches sarthak Sawarkar, working in the laboratory of Professor Manel Lopez-Bejar in Barcelona with colleagues from MedAnswers Inc in the USA.

The study, which is still ongoing, now reports the results of the 152 women whose hair and blood samples were regularly collected during hospital visits. AMG measured in the serum of the same theme were used to provide control, as the number of operations an ultrasound of the developing follicles in the ovaries (AFC) as additional measures of ovarian reserve.

“Biologically relevant” levels of AMG were successfully detected in hair samples, with levels decreasing with patient’s age, as expected.

As ovarian reserve declines with age, so that the levels of AMG. The levels of AMG from hair correlates with level in the blood serum and the frequency response. It was also seen that this test was able to detect a wide range of AMH levels within individuals of the same age group, which indicates a greater accuracy than from a single blood sample.

The hormones accumulate in the hair for several months, while the hormone levels in the blood can change within hours. “So the hair,” explain the authors, “is a tool that can accumulate biomarkers for several weeks, while serum is a sharp matrix is just the current levels.

While the level of hormone in the blood can change dramatically in response to stimuli, hormone levels measured in the hair represent the accumulation over a few weeks. Measurements using a hair sample are more likely to reflect the average level of hormones in man.”

Among other advantages, test the hair, the authors note that the hormone level is assessed non-invasively, which reduces the stress testing and offers a less expensive analysis.

Testing can be done without visiting the clinic and thus makes this type of test available to a wider range of women.

“Finally,” explains Mr. Sawarkar, “how hair offers insights into the long-term accumulation of hormones, this measurement may contribute to a better understanding of the individual hormone levels, unlike blood-based tests only measure the hormone at the time of testing.”

AMG still was an important, though sometimes controversial role in reproductive medicine.

Thus, while its role as an indicator of ovarian reserve in predicting response to ovarian stimulation for IVF now, it seems, beyond doubt, was no doubt of its wider application as a measure of the fecundity of females in the population as a whole.

Commenting on the biology test, Mr. Sawarkar explains that the hormones involved in the hair matrix Before growing hair on the surface of the skin, thereby enabling to accumulate the determination of the concentration of hormones.

.



image source

Single-cell RNA-seq answers key questions in islet cell biology and diabetes research | Instant News


The pancreas is a stomach organ that produces digestive enzymes and hormones that regulate blood sugar levels. This hormone-producing function is localized on the island of Langerhans, which forms a group of various types of endocrine cells.

Among these are beta cells, which produce the hormone insulin which is needed to lower glucose levels (a type of sugar) in our blood, as well as alpha cells, which produce glucagon hormones whose job is to increase glucose levels in the blood.

Type 1 diabetes is a chronic disease where the immune system mistakenly attacks and destroys pancreatic insulin-producing beta cells. Regenerative medicine aims to replenish beta cell mass, and thus support and ultimately replace current insulin replacement therapy.

Changes in island composition, including lack of beta cell function and beta cell dedifference, also contribute to type II diabetes.

Therefore, a deeper understanding of the identity and crosstalk of various islet cell types leads to better characterization of both forms of diabetes and can contribute to the development of new therapeutic concepts.

Single cell transcriptomes are powerful techniques for characterizing cellular identity. Previously, CeMM researchers from the groups Christoph Bock and Stefan Kubicek at CeMM published the first single cell transcriptome from primary human pancreatic islet cells.

Advances in technology have enabled applications for the generation of global single cell atlase human and mouse transcript. Despite this progress, the single cell approach remains technologically challenging given the very small amount of RNA used in the experiment. Therefore, it is important to ensure the quality and purity of the resulting single cell transcriptome.

CeMM researchers in two laboratories who contributed unexpectedly identified high hormone expression in non-endocrine cell types, both in their own dataset and published single cell studies.

They set out to explain whether this would be the result of contamination by RNA molecules, for example from dying cells, and how they could be removed to obtain a more reliable dataset.

Such contamination appears to be present in RNA-seq single cell data from most tissues but is most visible on pancreatic islets. Islet endocrine cells are exclusively devoted to the production of a single hormone, and insulin in beta cells and glucagon in alpha cells is expressed to a higher level than a typical “household” gene.

Thus, the redistribution of these transcripts to other cell types is very clear. Based on these observations, their goal is to develop, validate and apply methods to experimentally determine and computationally eliminate the contamination.

In their investigation, the CeMM researchers used prickly cells of different cell types, both rat and human samples, which they added to their pancreatic islet samples. Importantly, the transcriptomes of these spike cells are fully characterized.

This enables them to internally and accurately control the level of RNA contamination in a single RNA-seq cell, providing that the human transcripts detected in mouse spike-in cells are contaminated RNA.

In this way, they found that the sample had a contamination rate of up to 20%, and was able to determine the contamination in each sample. They then developed a new bioinformatics approach to computationally eliminate contaminated readings from single cell transcriptomes.

Having now obtained the “decontamination” transcriptome, from which false signals have been removed, they proceed to characterize how cellular identities in different cell types respond to treatment with three different drugs.

They found that small molecular blockers of the FOXO1 transcription factor induced dedifferentiation of both alpha and beta cells.

Next, they studied artemeter, which has been found to reduce alpha cell function and can induce insulin production in both in vivo and in vitro studies. Effects of species-specific drug species and cell types.

In alpha cells, a small proportion of cells increase insulin expression and gain aspects of beta cell identity, both in rat and human samples. Importantly, the researchers found that in human beta cells, there was no significant change in insulin expression, whereas in mouse islands, beta cells reduced insulin expression and overall beta cell identity.

This study is the result of interdisciplinary collaboration from the laboratories of Stefan Kubicek and Christoph Bock at CeMM with Patrick Collombat at the Institute of Biology Valrose (France).

This is the first study to apply single cell sequencing to analyze dynamic drug responses in intact isolated tissue, which benefits from the high quantitative accuracy of the decontamination method.

Thus not only provides a new method for single cell decontamination and a very quantitative single cell analysis of drug responses in intact tissue, but also answers current questions that are important in islet cell biology and diabetes research. These findings could open up potential therapeutic avenues for treating type 1 diabetes in the future.

.



image source