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Our hard-wired stress response is designed to gives us the quick burst of heightened alertness and energy needed to perform our best. But stress isn't all good. When activated too long or too often, stress can damage virtually every part of our body. Sharon Horesh Bergquist gives us a look at what goes on inside our body when we are chronically stressed.

Stress is implicated in increased tumor progression risk and poor survival in cancer patients. A number of recent studies have linked these effects to the promotion of tumor cell dissemination through the bloodstream via stress-induced pathways. Now, a mouse study led by researchers in Australia has revealed the mechanisms by which stress modulates cancer's spread through another transport network open to tumor cells-the lymphatic system.

Researchers at the University of Pennsylvania performed "stress tests" on pregnant mice using a predator's odor, restraint, or unfamiliar noises. After the mice gave birth, the scientists analyzed the bacterial communities in their vaginas and in their pups' colons. The researchers found that stress during pregnancy altered the expression levels of several proteins involved in vaginal immunity and the frequency of Lactobacillus bacteria, which, expectedly, correlated to lower frequencies of Lactobacillus within their pups' gut microbiomes. Male pups of stressed mothers also displayed an increase in anaerobic bacteria like Clostridium and Bacteroidesin.

Many things are passed down from mother to child, and now, research is finding that stress is on that list! Join Trace as he discusses how prenatal maternal stress can impact you later in life!

Stress isn't always a bad thing; it can be handy for a burst of extra energy and focus, like when you're playing a competitive sport or have to speak in public. But when it's continuous, it actually begins to change your brain. Madhumita Murgia shows how chronic stress can affect brain size, its structure, and how it functions, right down to the level of your genes.

Protein folding and trafficking is essential for normal cell function, and when it goes awry it can lead to various chronic conditions, including fatty liver disease, diabetes, and Parkinson's. The narrative of this case study follows two undergraduate students engaged in a summer research project evaluating the effects of cell stress on cell function and health in the model organism Caenorhabditis elegans (C. elegans).  During the case study, students review animal cell organelle function and then learn about endoplasmic stress and unfolded protein response. Prior knowledge needed for the case is basic animal cell organelles and their functions and use of model organisms in research. The case was designed for a flipped classroom in which students prepare in advance by taking a quiz and watching two videos; a PowerPoint animation is also included.

This interrupted case study introduces the topic of bacterial sporulation and cannibalism in Bacillus subtilis. The storyline follows Susan and her lab mates who are presenting research at a lab meeting when Susan falls asleep and dreams they are stranded on a deserted island. She makes connections between their fight for survival in the dream and the survival mechanisms of the bacteria they study in the lab. The benefits of sporulation under conditions of sustained stress are fairly obvious, but Susan's dream is used to examine the idea that sporulation may not always be beneficial and that bacteria would not want to commit to entering such a state in response to temporary stresses. Through the analysis of actual data from the scientific literature, students uncover a mechanism by which B. subtilis delays its commitment to sporulation by killing members of its own species to release nutrients (i.e., cannibalism). Originally developed for a general undergraduate microbiology course when discussing the structure and growth of prokaryotic cells, the case could also be used in an introductory biology course that emphasizes bacteria and data literacy.

Adverse life experiences, particularly those in childhood, contribute to disease morbidity and mortality [1, 2, 3, 4, 5, 6, 7]. There is considerable interest in understanding the mechanisms through which they do so, as it remains unclear how illness becomes apparent decades after the presumed initiating event. Long-standing hypotheses include chronic activation of the hypothalamic-pituitary-adrenal axis [8, 9, 10] and alterations of neuroimmune function [11]. Molecular signatures of stressful life experiences and their relation to disease are therefore of special interest to clarify the causal relationship between signature, disease, and stress.

This interrupted case study tells the story of Michael, a Harvard law graduate with a stressful job and a seemingly heavy drinking problem. Students are provided with background information, medical history, and lab results in order to guide them towards determining what is wrong with Michael. This study highlights cirrhosis and the effects of alcohol abuse on the liver. Before beginning the case study, students should have a background in the physiological role of the liver and the breakdown of hemoglobin. Students are asked to use the information provided for them in the case study to gather more information about liver cells and their functions, alcohol, and alcoholic liver damage. Ultimately, using multiple blood tests, the Maddrey's discriminant function (DF) score, and results from a magnetic resonance elastography (MRE), they will diagnose Michael with alcoholic cirrhosis. This case was developed for use in a non-majors physiology course, but could easily be used for a majors class.

Healthy plants reflect more near-infrared light than stressed plants, so bright red indicates dense, growing foliage. For this reason, biologists and ecologists occasionally use infrared cameras to photograph forests. 

After an exhaustive survey of contemporary epigenetics studies, one researcher has concluded that some of the effects of stress, cancer and other chronic diseases may be passed on to our offspring -- and theirs -- through deep and complicated underlying cellular mechanisms that scientists are just beginning to understand.

As a Sunday target date approaches for countries to submit to the United Nations their plans for fighting climate change, China is banding together with other major developing nations to stress that only the wealthier countries need to make internationally binding commitments.

A cornerstone of modern biomedical research is the use of mouse models to explore basic pathophysiological mechanisms, evaluate new therapeutic approaches, and make go or no-go decisions to carry new drug candidates forward into clinical trials. Systematic studies evaluating how well murine models mimic human inflammatory diseases are nonexistent. Here, we show that, although acute inflammatory stresses from different etiologies result in highly similar genomic responses in humans, the responses in corresponding mouse models correlate poorly with the human conditions and also, one another.

Biologists have long puzzled about how evolutionary selection, known for its ruthless requirement for efficiency, allows the existence of males - when in so many species their only contribution to reproduction are spermatozoa. But research published today in Nature shows that sexual selection - when males compete and females choose over reproduction - improves population health and protects against extinction, even in the face of genetic stress from high levels of inbreeding.

In this interrupted case study, students will help Dr. Gupta investigate and assess complications arising in one of her long-term patients, Jorge Alvarez. Jorge was diagnosed with Type II diabetes mellitus 10 years ago as documented in "Living the Sweet Life," an optional prequel case study also in the NCCSTS collection. Jorge has been working with Dr. Gupta to manage his condition, but this year he has come under additional stress, both emotionally and financially, and his health has deteriorated. Jorge now presents with several new signs and symptoms, including numbness, tingling and burning sensations, and a foot sore that just won't heal. Students will review the nervous system and assess Jorge's symptoms, vitals, and blood tests to determine if his diabetes has worsened. Students will also learn about tests used to diagnose types of neuropathy and consider which of them would be most beneficial for Jorge. In addition to a non-majors anatomy and physiology course, this case study may be appropriate for an introductory biology, nutrition/dietetics, or a sensory and perception course.

Why do we smell different when we're sick? Why does cheese smell like feet? Why don't vultures get sick from eating rotting meat? Science is filled with stories: some of them are beautiful and some of them are gross. Really gross. Gross Science, a YouTube series hosted by Anna Rothschild, tells bizarre stories from the slimy, smelly, creepy world of science. In this collection, you'll find original short-form videos and DIY experiments from Gross Science, which is produced by NOVA and PBS Digital Studios. Learn about amphibians that eat their mother's skin, strange uses for bacon, how poop can be used to cure an infection, and more gross science topics.

Loss of species richness is often due to anthropogenic activity. The global decline of amphibians is one such example. This case study examines the impact of road deicing agents on amphibians living near bridges and roads treated heavily with salt during the winter months. Concepts explored in this case include changes to the aquatic environment as a result of road deicing applications, bioaccumulation, osmoregulation in amphibians living in clean freshwater, and the impact of increased aquatic salinity levels on the ability of amphibians to adequately osmoregulate in an environment for which they are not adapted. Three short videos created by the author can be shown in class or assigned for viewing in advance for a "flipped" classroom approach. Originally developed for a general education/introductory biology course, the case could also be used with introductory level animal anatomy and physiology courses as part of a deeper exploration of the renal system.

Dean Ornish shares new research that shows how adopting healthy lifestyle habits can affect a person at a genetic level. For instance, he says, when you live healthier, eat better, exercise, and love more, your brain cells actually increase.

Scientists were investigating a tantalizing but controversial hypothesis: that a man's experiences can alter his sperm, and that those changes in turn may alter his children.

Have you ever heard that you become more powerful in life-or-death situations? There are a lot of anecdotes about super strength, but is it a real thing?