Tag: mice

Posted on

Is It Cancer? Check Your Ink

Mouse tattoos
Calcium detecting tattoos in mice

In recent years increased research has been done on the medical applications of tattoos, they have proven effective in delivering drugs, administering vaccines, and working as blood sugar level sensors in conjunction with skin based electronics. New research out of Switzerland, published in Science, has essentially invented a tattoo that can detect cancer. The tattoo “ink” is injected under the skin, and only becomes visible when it detects elevated calcium levels in the blood, an indicator of breast cancer, colon cancer, lung cancer, and more.

 

The procedure was developed and demonstrated in mice using reprogrammed calcium detecting cells to produce melanin, a black pigment which color moles and freckles. Thus the tattoo would be invisible when administered, but would appear as a large black dot if blood calcium levels became consistently elevated, as in many types of cancer. Perhaps the greatest difficulty in cancer treatment is diagnosis; by the time a patient notices symptoms and seeks medical attention, the disease may have already begun to grow aggressively. By administering these dormant monitors in people, particularly those at a high risk, cancer can be detected as soon as physiological changes begin.

 

The tattoo ink is actually made from calcium detecting cells that humans use to regulate calcium in the blood. Calcium is an essential compound for maintaining functions like cell growth, cell death, cell movement and more. But its concentration is precisely regulated, if there is too little the bone marrow will produce more, if there is too much, the bones will stop producing it. So when calcium does become elevated it is usually corrected in a few minutes. But certain cancers can inhibit the hormone that acts to regulate calcium production, and so calcium levels remain consistently elevated.

 

Though there are other pathologies that can cause elevated calcium levels, the tattoo worked well in mice to detect certain cancers before they became symptomatic. It has also been shown to be resilient to short term fluctuations in blood calcium levels and would be especially useful for patients who display risk factors for these cancers such as those with a diagnosed parent, a history of smoking, or work in hazardous environments.

 

But even if it is best used in niche applications, this represents a dramatic shift towards an entirely new field of diagnostic tests. Human beings can already have their DNA analyzed and identified for specific disease risk factors, if similar tattoos can be created for Celiac Disease, Parkinsons, Alzheimers, and the rest, then medical attention can be sought and treatment strategies implemented when the disease has only just taken hold, when it is at its most treatable.

 

Tastanova A, Folcher M, Müller M, Camenisch G, Ponti A, et al., (2018) Synthetic biology-based cellular biomedical tattoo for detection of hypercalcemia associated with cancer. DOI: 10.1126/scitranslmed.aap8562

Posted on

Ketamine for Dopamine: Club Drug Cures Depression?

Recently ketamine has come under focus for its notable effects treating depression. A new study seeks to identify the pathway that allows its rapid anti-depressant effects. The horse tranquilizer turned party drug may have found another niche. The study was published in Nature, funded by the National Key R&D program of China.

As this research is in its introductory stages, researchers used a mouse model instead of human subjects. To simulate depression symptoms, rats were specifically bred as “Congenitally Learned Helpless” and mice as “Chronic Restraint Stress”. The animals were then injected with Ketamine and their behavior or electrophysiology was examined.

The findings revealed that the ketamine works by inhibiting the NMDAR pathway, nicknamed the “anti-reward center”. Burst evoking stimulation of this pathway has been show to lead to depressive behavior and anhedonia. By inhibiting the NMDAR, downstream reward centers have been shown to quickly elevate mood and produce rapid acting anti-depressant effects.

This research does not address the question of what the long-term effects of ketamine are, and its utility may lie in helping to understand the pathways that regulate depressive mood rather than paving the way for ketamine prescriptions as an antidepressant, being that it has a significant potential for abuse (not to mention a sorted reputation).

Anti-depressants tend to focus on boosting serotonin and dopamine expression to elevate mood, but by understanding and manipulating the pathway that inhibits their expression, a more targeted and effective treatment can be administered. The discovery of the NMDAR antagonist and its rapid anti-depressant effects has been called the most important advance in psychiatry in the last century. We live in an age where clinical depression has become relatively commonplace, and the recently discovered effects of Ketamine as this critical antagonist cannot be ignored.

 

Yang Y, Cui Y, Sang K, Dong Y, Ni Z et. al. (2018) Ketamine blocks bursting in the lateral habenula to rapidly relieve depression. Nature 554: 317-22