The researchers put mice on a diet and assessed which circuits in the brain changed. In particular, they examined a group of neurons in the hypothalamus, the AgRP neurons, which are known to control the feeling of hunger. They were able to show that the neuronal pathways that stimulate AgRP neurons sent increased signals when the mice were on a diet. This profound change in the brain could be detected for a long time after the diet.Max Planck Institute for Biology of Ageing. “Dieting: Brain amplifies signal of hunger synapses: Possible target for drugs to combat the yo-yo effect.” ScienceDaily. http://www.sciencedaily.com/releases/2023/03/230324135218.htm (accessed March 28, 2023).
Omicron booster shots are coming—with lots of questions – Updated 9/2/22
The new shots target both the original strain of the coronavirus and the omicron BA.4/BA.5 subvariants that most people are catching now. This double-barreled vaccine is called a bivalent vaccine. https://www.npr.org/sections/health-shots/2022/08/31/1120241293/fda-authorizes-first-revamp-of-covid-vaccines-to-target-omicron
For the BA.4/BA.5 boosters, the companies have submitted animal data. They have not released those data publicly, although at the June FDA meeting, Pfizer presented preliminary findings in eight mice given BA.4/BA.5 vaccines as their third dose. Compared with the mice that received the original vaccine as a booster, the animals showed an increased response to all Omicron variants tested: BA.1, BA.2, BA.2.12.1, BA.4, and BA.5.Omicron booster shots are coming—with lots of questions — https://www.science.org/content/article/omicron-booster-shots-are-coming-lots-questions
Some answers to commonly asked questions can be found in the Stat article.
On Thursday evening, Centers for Disease Control and Prevention Director Rochelle Walensky signed off on the recommendation made earlier in the day by the Advisory Committee on Immunization Practices, that the newly formulated vaccines be used.Your questions on the new Covid vaccine boosters answered — https://www.statnews.com/2022/09/01/your-questions-on-the-new-covid-vaccine-boosters-answered/
Diet-induced Alteration of Intestinal Stem Cell Function (in mice)
“The first thing we noticed was that the small intestine increases greatly in size on the high-calorie diet,” says study leader Anika Böttcher. “Together with Fabian Theis’ team of computational biologists at Helmholtz Munich, we then profiled 27,000 intestinal cells from control diet and high fat/high sugar diet-fed mice. Using new machine learning techniques, we thus found that intestinal stem cells divide and differentiate significantly faster in the mice on an unhealthy diet.” The researchers hypothesize that this is due to an upregulation of the relevant signaling pathways, which is associated with an acceleration of tumor growth in many cancers. “This could be an important link: Diet influences metabolic signaling, which leads to excessive growth of intestinal stem cells and ultimately to an increased risk of gastrointestinal cancer,” says Böttcher.Helmholtz Zentrum München – German Research Center for Environmental Health. “New link between diet, intestinal stem cells and disease discovered.” ScienceDaily. http://www.sciencedaily.com/releases/2021/11/211119155604.htm (accessed November 27, 2021).
I wonder what Dr. Lustig would say about this study?
Dr. Robert Lustig – The Sugar Pandemic – 2012 Presentation at Yale University and Dr. Robert Lustig on Sugar.
SARS-CoV-2 Variants – (in mice)
Pre-print therefore not peer reviewed. No, I don’t hang out on Twitter all day long. Yes, the study is somewhat geeky. BUT here’s the money sentence:
This abrogation of the species barrier raises the possibility of wild rodent secondary reservoirs and provides new experimental models to study disease pathophysiology and countermeasures.The B1.351 and P.1 variants extend SARS-CoV-2 host range to mice — https://www.biorxiv.org/content/10.1101/2021.03.18.436013v1
Now I can’t stop thinking about “secondary reservoirs”.
ACE2-interacting domain of SARS-CoV-2
In a study published in the Journal of Neuroimmune Pharmacology, mouse models with COVID-19 showed positive results when a small peptide was introduced nasally. The peptide proved effective in reducing fever, protecting the lungs, improving heart function and reversing cytokine storm — a condition in which an infection triggers the immune system to flood the bloodstream with inflammatory proteins. The researchers also report success in preventing the disease from progression.Rush University Medical Center. “Potential COVID-19 drug is successful in lab study: Peptide reduced COVID-19 symptoms in mice.” ScienceDaily. http://www.sciencedaily.com/releases/2021/01/210119194322.htm (accessed January 20, 2021).
Journal Reference – Ramesh K. Paidi, Malabendu Jana, Rama K. Mishra, Debashis Dutta, Sumita Raha, Kalipada Pahan. ACE-2-interacting Domain of SARS-CoV-2 (AIDS) Peptide Suppresses Inflammation to Reduce Fever and Protect Lungs and Heart in Mice: Implications for COVID-19 Therapy. Journal of Neuroimmune Pharmacology, 2021; DOI: 10.1007/s11481-020-09979-8
Our neighbor Dr. Arlan Richardson at https://nathanshockcenters.org/oklahoma part of the University of Oklahoma Health Sciences Center knows a lot about mice. I’ll have to ask him what he thinks of the potential of this peptide for human use.
N501Y mutation in SARS-CoV-2 virus causes increased infectivity, disease severity in mice — Science Chronicle
Chinese researchers found N501Y mutation in a mouse-adapted SARS-CoV-2 virus strain. In the mouse model, the N501Y mutation was found to increase the binding affinity of the virus with the mouse ACE2 receptor. The mutation in the mouse-adapted strain also caused increased virulence. In a preliminary report posted on December 19, Dr. Andrew Rambaut from […]N501Y mutation in SARS-CoV-2 virus causes increased infectivity, disease severity in mice — Science Chronicle
Interesting article and the last paragraphs must be emphasized.
Dr. Gagandeep Kang, Professor of Microbiology at CMC Vellore, however, cautions that emergence of N501Y mutation has been seen on other occasions. According to her, the N501Y mutation in a strain that has been adapted to infect a mouse model cannot be compared with the N501Y mutation seen in the new variant infecting humans. And the severity of diseases caused by the mutation in the mouse model has no relevance to humans, she says.
“At this time, one can only say the mutation increases binding affinity in humans and hence increased transmissibility. Nothing can be said about disease severity,” says Dr. Kang.
Visceral fat delivers signal to the brain that hurts cognition
“We have identified a specific signal that is generated in visceral fat, released into the blood that gets through the blood brain barrier and into the brain where it activates microglia and impairs cognition.”
Visceral fat delivers signal to the brain that hurts cognition
Quote and article link presented without the usual sarcasm.
Molecule found in oranges could reduce obesity and prevent heart disease and diabetes
In mice, so don’t start gorging on oranges.
Sorry, sarcasm restriction didn’t last long.
Early studies on the diet suggested red wine was a major contributor to the health benefits of the Mediterranean diet because it contains a compound called resveratrol, which activated a certain pathway in cells known to increase lifespan and prevent aging-related diseases. However, work in Mashek’s lab suggests that it is the fat in olive oil, another component of the Mediterranean diet, that is actually activating this pathway.
Olive oil in the diet may also help mitigate aging-related diseases
High-protein diets boost artery-clogging plaque
High-protein diets boost artery-clogging plaque, mouse study shows
The mice on the high-fat, high-protein diet developed worse atherosclerosis — about 30% more plaque in the arteries — than mice on the high-fat, normal-protein diet, despite the fact that the mice eating more protein did not gain weight, unlike the mice on the high-fat, normal-protein diet.
“This study is not the first to show a telltale increase in plaque with high-protein diets, but it offers a deeper understanding of the impact of high protein with the detailed analysis of the plaques,” Razani said. “In other words, our study shows how and why dietary protein leads to the development of unstable plaques.”
Study finds electronic cigarettes damage brain stem cells (in cultured mouse neural stem cells)
A research team has found that electronic cigarettes, often targeted to youth and pregnant women, produce a stress response in neural stem cells, which are critical cells in the brain.
Study finds electronic cigarettes damage brain stem cells – UC Riverside research on mouse neural stem cells has implications for nicotine use
Longer daily fasting times improve health and longevity (in mice)
The scientists randomly divided 292 male mice into two diet groups. One group received a naturally sourced diet that was lower in purified sugars and fat, and higher in protein and fiber than the other diet. The mice in each diet group were then divided into three sub-groups based on how often they had access to food. The first group of mice had access to food around the clock. A second group of mice was fed 30 percent less calories per day than the first group. The third group was meal fed, getting a single meal that added up to the exact number of calories as the round-the-clock group. Both the meal-fed and calorie-restricted mice learned to eat quickly when food was available, resulting in longer daily fasting periods for both groups.
The scientists tracked the mice’s metabolic health through their lifespans until their natural deaths and examined them post-mortem. Meal-fed and calorie-restricted mice showed improvements in overall health, as evidenced by delays in common age-related damage to the liver and other organs, and extended longevity. The calorie-restricted mice also showed significant improvement in fasting glucose and insulin levels compared to the other groups. Interestingly, the researchers found that diet composition had no significant impact on lifespan in the meal fed and calorie restricted groups.
One of my neighbors is a mouse researcher. I bet he’s really excited this weekend.
The NIH webpage on caloric restriction and fasting diets is here.
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