Singapore Scientists Develop Drug Delivery Microbe That Travels Up the Nose

The Blood-brain barrier(BBB) is layer of protective cells which line the circulatory system connected to the central nervous system which regulates what can and cannot enter. This functions to ensure that dangerous microbes and other dangers do not pose a threat to the brain and central nerves which are imperative to life. Despite this robust security system, it has one flaw... the nasal cavity. Microbes which are capable of navigating to the central nervous system nasally via the olfactory nerve are able to bypass the blood brain barrier and cause havoc to human health. However, scientists had realised this pathway could be critical to drug delivery bypassing the liver and BBB and began to experiment with intranasal drug delivery. Researchers at the National University of Singapore have taken this concept a step further and have developed microbes to deliver drugs directly into the nervous system via olfactory nerves.

The binding of the microbe to olfactory sites and

the movement of drugs(+) to the CNS via the olfactory nerve.

        

The BBB and liver are major obstacles in drug effectiveness, where their protective and selective nature prevents many drugs from being absorbed to their fullest potential. The researchers identified a myriad of nasal bacteria as candidates for this experiment, and ultimately decided upon Lactobacillus plantarum due to it's affinity for olfactory binding sites. The microbes were dyed to create fluorene for easier tracking, and then deployed into rats for live testing. The microbes remained in the nasal cavity while their drug payloads were diffused across the olfactory pathway into the central nervous system. The microbe underwent numerous edits via transformation in order to maximise olfactory binding and drug delivery, and the result was that the microbe administered drugs remained longer than those administered simply intranasally. While future studies and testing are needed to ensure that this method is safe, it is nonetheless a fascinating method of drug delivery and medical science. 

Sources:

https://phys.org/news/2025-02-bloodbrain-barrier-payload-bacteria.html

https://www.cell.com/cell/fulltext/S0092-8674(25)00046-7?_returnURL=https%3A%2F%2Flinkinghub.elsevier.com%2Fretrieve%2Fpii%2FS0092867425000467%3Fshowall%3Dtrue        

https://pubmed.ncbi.nlm.nih.gov/22465159/

 

The Axolotl's Superpower: Tissue Regeneration!

    This article discusses the sequencing of the axolotl genome, and how it may be significant in regards to human health/medical treatments. Axolotls are neotenic- in other words, they never reach "full maturity". This is how they keep their gills and continue to live underwater. They also hold the title for the largest genome ever fully sequenced. Scientists are particularly interested in researching axolotls for their incredible ability to regenerate lost tissues- even having the capability to regrow their spinal cords, and parts of their brains! Scientists may be able to learn from this ability and translate it into the medical field. Since axolotls have been used as model organisms, health-related events observed in them, such as heart problems, can be studied, and then used in respect to human health-related problems.

    I find this article to be incredibly interesting. The concept of utilizing the information axolotls provide regarding regeneration in a medical sense for humans is groundbreaking. I can only imagine the different manners in which it could be used to better our medical treatments- such as use on burn victims or use in combating degenerative diseases. It makes me wonder just how far we can push the bounds of this regenerative ability- I know we as humans will not be able to regrow entire limbs, but to what extent will we be able to practice this ability in the medical field? 

The Future of Hair: 3D-Bioprinting

The idea of combining hair follicles and 3D printing sounds like the start of a science fiction movie. The craziness of science fiction movies is well known. This experiment held by Rensselaer Polytechnic Institute showed an abundance of advantages to their remarkable innovation. By using 3D- bioprinting it offers to build upon the current knowledge obtained from skin grafting. 

Now, we are at the point where skin grafts can't fully mimic human skin without the production of hair. In order to understand why scientists are doing this, it's important to highlight the benefits of hair follicles. Hair follicles are most known for their supportive role. They provide benefits such as hair growth, thermoregulation, and protection with a much needed thank you to our stem cells that aid the skin to heal. 

It's already hard to believe that 3d-bioprinting can be successfully done at a cellular level. The printers can effectively produce skin tissue with working blood cells, which is amazing. It’s almost impossible to comprehend. However, we are still at the start of this sci-fi movie. Scientists are consistently working in order to achieve an even bigger goal. Not only are they working on skin grafts with hair follicles that strangely mimic our skin, they also would like to explore the unknown treatments, hair rejuvenation, tropical drug testing, and dermatological testing that can further expand our current knowledge of the skin.

 This sounds great, but we are nowhere near achieving these goals. it does make sense; the skin is the largest organ of the human body, providing an extra layer of complexity.  The main issue currently is the 3D printed hair follicle lifespan only lasting up to three weeks. Therefore, research on expanding the lifespan of hair follicles is necessary and a top priority. The main objective is to allow the hair shaft and soon enough hair follicles to mature. Once accomplished, it could be safe to say life is a true sci-fi movie. Moreover, it’s wonderful to envision the plethora of innovations that this technology could open the door for. 

Links: 

https://www.sciencedaily.com/releases/2023/11/231115113440.htm

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8283073/

https://www.youtube.com/watch?v=f7Y_gf6DD5E

Potential Issues in Precision Medicine

The focus of this article was to bring up potential issues that could arise in medical genetic testing. The author of the article stated that there was a girl who had been misdiagnosed for DiGeorge Syndrome. After her misdiagnosis it was later determined that she did not have a missing fragment on chromosome 22.

The author then cited another incident where a women underwent extreme surgery to remove her uterus. It was later determined that the genetic test was read wrong and that the surgery was unnecessary. The risks for misinformation also included maternity care. Which according to the author is not a definitive as some doctors believe it is to be.The author then brings up the issue that medical doctors are not properly trained to diagnose genetic information because most of them were already practicing medicine while the first human genome was being sequenced.

In my opinion the the author brings up a pretty good point on potential malpractice incidents due to medical genetic testing. However I disagree with the author when they said that doctors should be trained in the field of genetics along with everything else they have to know. Doctors have to many things going on to effectively and accurately use genetic testing as a means of preventative healthcare.In my opinion this could and should open a new career path in the medical industry in the years to come.


http://www.newyorker.com/tech/elements/problem-precision-medicine

Bacteria the Future of Hard Drives

Engineers at MIT have transformed the genome of E. coli into a storage device.  To make the E. coli bacteria into a storage device, they had to engineer the cells to produce a recombinase enzyme.  This would allow them to insert DNA (or a sequence of DNA), which would only activate during certain circumstances or input.  After the DNA is activated, the bacteria would pass the information down to each generation allowing for long term memory. 

Timothy Lu, electrical, computer science, and biological engineer, explained the engineered bacteria has the potential to advance medical and environmental sensors. It could potentially detect increased carbon dioxide in the ocean, or detect infections/disease in humans.  This type of information could then expedite medical help; instead of wasting type determining the problem, a doctor could go straight to medical procedures.

The idea of using bacteria as storage devices for information is not new.  In fact using bacteria to store information was attempt in 2001 and 2007 with no success.  In 2010, Chinese Biochemistry students developed a way to use bacteria as a way to store electronic data.  They estimated they could use bacteria as a sort of “bio-hard-disk” to store up 900000 gigabytes, or 450 two terabyte (2000 GB) hard drives.  And because they are bacteria, they can reproduce and ensure the data is store permanently.  This could easily advance biotechnology further than it already has been.

Figure 2 The largest storage device has a capacity of 320MG.  Bacteria has more than 2800 times that.

The fact we have come so far as to be able to use bacteria as storage devices, is nothing short of incredible.  I knew were advancing further and further with bioengineering and biotechnology, but to see and read about its fruition excites me.  The advances we could make in the fields of technology, environmental, and medical sciences is amazing.  The two articles (one for technology and one for medical/environmental) show the scientific community is constantly advancing and working to make a better world.

Article: http://www.sciencedaily.com/releases/2014/11/141113142006.htm 

Related Article: http://www.digitaljournal.com/article/300831 

HDAC6 mutations rescue human tau-induced microtubule defects in Drosophila

 

The search for cures and understanding of diseases is paramount to survival of the fittest. The use of the Drosophila (common fruit fly) is being used to account for neural transmissiion in Alzheimer Dissease. Amazingly the HDAC6 mutation is seen not only in this small organism but also in mice. One more step toward understanding and hopefully a cure or at least a delay in Alheimer patients.

Neurons from the brains of Alzheimer’s disease (AD) and related tauopathy patients contain neurofibrillary tangles composed of hyperphosphorylated tau protein. Tau normally stabilizes microtubules (MTs); however, tau hyperphosphorylation leads to loss of this function with consequent MT destabilization and neuronal dysfunction. Accordingly, MT-stabilizing drugs such as paclitaxel and epothilone D have been shown as possible therapies for AD and related tauopathies. However, MT-stabilizing drugs have common side effects such as neuropathy and neutropenia. To find previously undescribed suppressors of tau-induced MT defects, we established a Drosophila model ectopically expressing human tau in muscle cells, which allow for clear visualization of the MT network. Overexpressed tau was hyperphosphorylated and resulted in decreased MT density and greater fragmentation, consistent with previous reports in AD patients and mouse models.

http://www.pnas.org/lookup/suppl/doi:10.1073/pnas.1207586110/-/DCSupplemental

Evolution of neuronal changes in the course of Alzheimer's disease. http://www.ncbi.nlm.nih.gov/pubmed/9700651

Single-Neuron Observations Mark Steps in Alzheimer's Disease

Apr. 20, 2012 http://www.sciencedaily.com/releases/2012/04/120420105831.htm

Genetics May Help Explain Placebo Effect, Researchers Say

The placebo effect is when a patient is given a treatment that they believe will help their condition, however the actually treatment has not really been proven to work (Freeman 2012). According to researchers, a patient's response to a placebo is based largely on genetics. In a trial dealing with irritable bowel syndrome, patients were given what they believed to be acupuncture treatment. One group received no treatment at all, a second group received fake acupuncture with little or no face to face contact with the specialist, and a third group received the same fake acupuncture, but was given more interaction with the acupunturist.



What was found was that patients containing two copies of the allele methionine showed a positive response to the placebo. Patients with two copies of the valine allele were less likely to response to the placebo. Interestingly, even the patients who contained the two alleles of methionine responded better to the fake acupuncture when they had more interaction with the caregiver. This suggests that personal interaction may have something to do with the response.

I would like to read more about the genetic relationship that the placebo effect has when used in the treatment of a different syndrome. I am skeptical because irritable bowel syndrome has been shown to be anxiety related, therefore the results could have been due to the patient feeling more relaxed about having received a treatment, or about speaking to a physician. The results may be different if the patients were instead complaining of arthritis, or something else musculoskeletal.

Freeman S. How the placebo effect works. 2012. [Internet.] http://health.howstuffworks.com/medicine/medication/placebo-effect.htm