Buzz Off: What Happened to All the Insects?

Most of us don’t give much consideration to some of the smaller participants of our everyday life – the insects. They’re a constant facet of daily existence, even when relegated to background noise. But if you can think back to the presence of insects in your life, maybe ten, fifteen years ago, was it different? Even if you can remember longer than twenty-seven years ago, you might not be able to say with absolute certainty that there’s been about a 76-82% decrease in the biomass of aerial insects, but you’ve probably noticed a pretty significant shift in the sheer number of bugs you encounter in a day. The cicadas don’t sing quite as loud at night, the buzzing of flies is a less frequent annoyance, and you’ve definitely been cleaning fewer bugs off your windshield in recent times.

Scientists of one German entomological society, however, can say with certainty that in the last twenty-seven years there’s been a 76-82% decrease in the biomass of aerial insects at natural areas across Germany [1]. Similar studies across the world have been less singularly focused on insect disappearances, but many have noted similar trends in biomass declines  [2]. A decrease in overall biomass is a different conversation than one strictly about biodiversity and species extinction, but the effects are just as threatening to earth’s ecosystems and warrant some serious inspection.

The German study that incited these worries of a so-called “Insect Armageddon” began collecting data of aerial insect biomass at ninety-six protected areas in 1989, and the experiment continued until 2016. Scientists were baffled by the drastic results – over a 75% drop – which far outpaces the global estimate of 58% decline of vertebrates from 1970-2012 [1]. They also found that biomass loss is the highest in the summer, and is occurring across all habitats. Shockingly, at the moment there seems to be no clear-cut main cause of this massive decline. Climate change and human land use were initially suspected as major factors, but the study did not produce enough evidence for a direct correlation between either of them. Agricultural intensification seemed to have a stronger effect on the losses, but again, not substantial enough  to be the sole cause of this devastation [1].

Insects compose an enormous portion of one of the primary trophic levels. They are pollinators, decomposers, population controls, and a key part of nutrient cycling [2]. This massive decrease in their biomass – explicitly localized to natural areas of Germany in this study, but noted all the same by scientists around the world – affects everything else that lives in this world, from tiny plants to megafauna and even humans. A world without insects would be uninhabitable for a large percentage of all organisms alive today – and a very quiet place indeed.

References:

(1)  Hallmann, C. A.; Sorg, M.; Jongejans, E.; Siepel, H.; Hofland, N.; Schwan, H.; Stenmans, W.; Müller, A.; Sumser, H.; Hörren, T.; Goulson, D.; de Croon, H. More than 75 percent decline over 27 years in total flying insect biomass in protected areas. PLoS ONE 2017, 12 (10).

(2) Jarvis, B. The insect apocalypse is here. The New York Times Magazine. November 27, 2018.

Humans: Are We Really Just Crabby People?

I’m sure many of us have heard the term “cut-throat.” A rather negative adjective, this word describes individuals who will do anything to succeed - essentially “cutting the throats” of others to get ahead. While we may not identify with this harsh term, we may empathize more with the description “crabby”. This comparison to crabs may appear harmless, but the “crab mentality” can be just as unhealthy as a “cut-throat” perspective.

The crab mentality describes how a lone crab in a bucket can pull itself out and escape. However, with multiple crabs, no crab can leave because the bottom crabs pull down those trying to climb out. This seems extremely counterintuitive, but the crab mentality is a common analogy and explanatory model for human society.

The crab mentality can explain many everyday experiences, thoughts, and behaviors. How many times have other people silently wished for us to fail? How many times have we wanted other people to be unsuccessful? The crab mentality is a very common, yet often unacknowledged mindset with significant consequences on happiness and wellbeing. Learning about this phenomenon can allow our metamorphosis from crabs to caring, supportive humans, and in turn, be much happier. In addition, understanding the crab mentality can help us escape any toxic and negative environments created by the crabs around us.

What makes us hold these negative wishes for those around us? Why do we want others to fail? Sam Woolfe, a freelance writer that specializes in psychology and self-development, states that the crab mentality can stem from multiple causes, such as envy, low self-esteem, insecurity, and a competitive nature. We tend to think that these unsupportive thoughts make us happier because in the moment we might feel better: if someone else doesn’t succeed, it means we’re not failing. Yet, while it may liften our mood, this feeling is transient and can fuel a continuous cycle of feeling unworthy and incompetent. Instead of viewing friends as people we can look up to and mutually support, the crab mindset portrays them as competition that we must beat. What’s worse about the crab mindset is that it involves multiple crabs: just as you do with other people, they may do to you. The environment you’re in may want your failure just as much as you want them to not succeed, which could lead to fake support and less self-development.

However, we can all work towards overcoming the crab mentality. If you sense negativity from your current environment, you can distance yourself and find an empowering group to escape the trap. Supportive groups include joining a mastermind group, working with accountability partners for specific goals, signing up for classes you’re interested in, and so much more. These counteract the dangerous effects of the crab mentality by promoting an encouraging and supportive environment, surrounded by passionate people who strive for all-around growth. This positive environment acts not only as a ladder to leave the bucket, but also as a scaffolding to help push you out. The crab mentality may feel like the only option to feel secure in yourself, but being happy for others can actually motivate you and promote your own success and development. With mutual support and respect, we can all climb over the bucket!

References:

1. Image: https://www.kisspng.com/png-beach-blog-clip-art-bucket-clipart-1830810/download-png.html

2. Scott, S. (2019, January 02). What Is the "Crabs in a Bucket" Mentality? Retrieved from https://www.developgoodhabits.com/crabs-bucket/

3. Woolfe, Sam. (2018, July 11). The Crab Mentality: Why Can’t We Be Happy for Other People’s Success? Retrieved from https://www.samwoolfe.com/2018/07/crab-mentality.html

First Successful Restoration of Partial Sight in Mice

The nursery rhyme “Three Blind Mice” now describes a thing of the past, considering recent developments in the recovery of eyesight in blind mice. Previously, no cure existed for blindness, which was thought to be a permanent condition. The research conducted by the Stanford University School of Medicine, however, proves otherwise.

A team led by Andrew Huberman, an associate professor of neurobiology who heads a neural vision lab at Stanford, explored the growth of optic nerves of mice to find potential methods of reversing potential damage. Vision is only possible when light bounces off an object and enters the eye. There, the lens focuses the light onto the retina, where photoreceptor cells detect and transmit the information to retinal ganglion cells; once the axons of those cells are damaged, they cannot regenerate as the mTOR pathway, a growth-enhancing sequence of molecular interactions, tails off over time.  Since retinal ganglion cells are the only ones that link the eye to the brain, any damage to them results in blindness.

Huberman and his team crushed the nerve in one eye of the mice, but kept the photoreceptor cells and their connections to the retinal ganglion cells intact. They observed that the axons that connect the eye to the brain immediately began to shrivel, disrupting the interconnecting signals and causing blindness.

The researchers soon found that the use of nerve-growing chemicals and visual stimulation could alter this outcome. They exposed one group of  mice to biochemical manipulations that increased the activity of mTOR pathway within the retinal ganglion cells, another group to high-contrast images of a moving black and white grid, both of which exercised the axons and prevented their atrophy, and the rest to both forms of treatment. The researchers found that only the mice that received both procedures saw drastic improvement in their vision. When the procedures were completed before the optic nerve was completely lost, the procedures salvaged the axons, allowing them to regenerate despite having been completely severed. Besides producing a 500-fold increase in axon regrowth,  this study also shows that axons seem to permanently retain instructions for appropriate connections to the brain; in other words, “...Neurons remember the way home; they never forget,” said Huberman.

But how much of this regrowth actually translates to a restoration of sight? After three weeks of the treatment, the researchers conducted four different tests to see the potential for long-term improvement of vision in the mice. Most of the mice passed one test concerning larger objects and movement, which involved the projection of an expanding dark circle that mimicked the approach of a predator. The majority of the mice noticed and headed towards safety, confirming that most of the axons had reattached to their proper respective locations in the brain. These findings also indicated that the mice had at least partially recovered from their blindness because they were able to respond to the projection.

However, the mice were unable to discern finer details in the the other tests. Thus, the researchers were able to confirm that axons from two specific retinal ganglion cell types successfully reached their targets, but not those of other relevant cell types, of which there are 30 or so. To make further progress, a better understanding of the variety and the complexity of those cells is needed in order to determine how to best help a greater number of the axons successfully recover and reestablish connections with their respective structures of the brain.

These findings have many implications for the remedying of blindness in humans. Glaucoma, pituitary tumors, brain cancers, and general injuries can all cause optic nerve damage and subsequently, blindness. With this new research, doctors could potentially revert damage to the optic nerve, as long as they detect it before the nerves completely deteriorate.

Huberman and his team will continue to work on the project and is hopeful that something will come into fruition within five years.

References:

1. Park, Alice. (2016, July 11). In a scientific first, blind mice regain eyesight. Retrieved April 14, 2017, from http://time.com/4399255/mice-blindness-cure/

2. Goldman, Bruce. (2016, July 11). First-ever restoration of vision achieved in mice. Retrieved April 14, 2017, from https://med.stanford.edu/news/all-news/2016/07/first-ever-restoration-of-vision-achieved-in-mice.html

3. Paddock, Catharine. (2016, July 12). Scientists restore key parts of vision in blind mice for first time. Retrieved April 14, 2017, from http://www.medicalnewstoday.com/articles/311600.php

Is Stress a Carcinogen?

Stress is either labeled “good” or “bad” depending on the situation. While people usually consider carcinogens as chemicals or inanimate things that affect the body and regulate cancer processes, chronic stress is something that dangerously affects your life and increases your risk of getting cancer. It is important to differentiate the differences between acute stress and chronic stress. Acute stress, characterized by sudden onset and short duration of symptoms, can be beneficial in some situations, but can also lead to conditions such as numbness, depersonalization, and event dissociative amnesia.  However, the good thing about this stress is that it motivates yourself to study more and harder because you want to achieve a good grade. Acute stress can lead to productivity and give a sense of urgency to all of our tasks, which is crucial to make strides in our everyday life. While acute stress is a good thing, chronic stress is a whole other issue.

Chronic stress is defined as the response to emotional pressure suffered for a prolonged period of time in which an individual has little or no control. This chronic stress is deeply involved in the endocrine system, which releases stress-causing hormones such as cortisol and norepinephrine that can  dysregulate the body. Chronic stress induces cancer by suppressing Type 1 cytokines and protective T cells, while also increasing regulatory/suppressor T cell numbers. It is thought to be in the etiology of many diseases, and has several immunosuppressive effects.

These stresses include financial burdens, being overworked, traumatic experiences, unavailability of health care, family instability, unemployment, and societal pressures. This constant stress can cause people’s health to decline, as their bodies is not able to deal with all of the chronic stress. This increased vulnerability within the body further facilitates different biological mechanisms that can disrupt the homeostasis that occurs in our body. For example, the hormone cortisol is released in response to stress; upon release, cortisol inhibits a process known as anikois, which kills diseased cells and prevents them from spreading. Additionally, stress hormones such as cortisol prevents T-cell proliferation, which dramatically reduces the strength of the immune system.

People deal with stress in different types of ways. Some may be beneficial, but some are deleterious. Often times, people resort to coping strategies such as substance abuse, dropping out of school, neglect, and avoiding all of their responsibilities. This, in turn, increases the body’s susceptibility to cancer causing reagents. However, there are activities such as physical exercise, group therapy, and counseling that can assist people dealing with this adverse stress.

References:

1. Chen, G. Y., & Nuñez, G. (2010). Sterile inflammation: sensing and reacting to damage. Nature Reviews Immunology, 10(12), 826.

2. Grivennikov, S. I., Greten, F. R., & Karin, M. (2010). Immunity, inflammation, and cancer. Cell, 140(6), 883-899.

3. Iliopoulos, D., Hirsch, H. A., & Struhl, K. (2009). An epigenetic switch involving NF-κB, Lin28, Let-7 MicroRNA, and IL6 links inflammation to cell transformation. Cell, 139(4), 693-706.

4. Stress and Cancer. (2012, July 27). Retrieved from https://www.stress.org/stress-and-cancer/

Genome Editing: A CRISPR Treat

Since its discovery, DNA has been proven to be an invaluable molecule in the field of biology. The molecule contains the information for life and holds in it our very essence. Despite DNA’s importance to life and science, easy manipulation of this molecule has proven to be very challenging. That’s why many have considered the discovery of the CRISPR/Cas9 system, which can add or remove parts of a DNA sequence with a high degree of specificity, to be a revolutionary new technology that has limitless potential.  

Process of insertion and deletion of DNA shown above. Figure courtesy of New England Biolabs

The CRISPR-Cas9 system consists of two key molecules that work together to produce the change in DNA [2]. One molecule is an enzyme called Cas9 which cuts the DNA at a specific site where the addition or deletion will occur [1]. The other molecule is called a guide RNA (gRNA) which binds to the DNA’s specific site and ‘guides’ Cas9 to the right part of the genome [1]. Together, these molecules ensure that the DNA will be modified at the proper location.

If the deletion of a gene is desired, we can then cleave the DNA at two sites--one at each end of the gene [1]. The two resulting strands of DNA (excluding the gene) will then recombine, forming a DNA sequence without the gene [1]. If the addition of a gene is desired, a donor strand of DNA with the desired insertion can be introduced in the system [1]. The previously cleaved DNA will each bind to one side of the insertion and then fuse to become one single DNA molecule again [1].

So why is any of this important? Many diseases, such as cancer, cystic fibrosis, and anemia, are the result of faulty mutations in DNA that create dysfunctional proteins [2]. Now imagine if we could simply change the mutated DNA back to its unmutated form. This is essentially what the CRISPR/Cas9 system allows us to do, which explains why so many people view the tool as the future of medicine. This potential has driven the start of several CRISPR/Cas9 trials in China for various types of cancer [3]. Due to stricter regulation, the US has not seen any trials yet, though the University of Pennsylvania had expressed its intention in 2017 to begin trials to treat melanomas and sarcomas [3]. Similarly, Stanford scientists and clinicians are trying to start a clinical trial aimed at curing sickle cell anemia through CRISPR/Cas9 [3].

Clearly, CRISPR/Cas9 holds great promise for the future of medicine. However, with great power comes great responsibility: the ability to easily edit DNA generates a great deal of ethical questions [2]. Much of this ethical debate stems around the potential use of gene editing on germline (reproductive) cells and the potential creation of designer babies [2]. How would society accommodate the development of such individuals and how would socioeconomic status come into play? These are all serious questions that must be considered and answered eventually, but for now let’s marvel on how far science has come.

References:

1. https://www.neb.com/tools-and-resources/feature-articles/crispr-cas9-and-targeted-genome-editing-a-new-era-in-molecular-biology

2. https://ghr.nlm.nih.gov/primer/genomicresearch/genomeediting

3. https://www.technologyreview.com/s/609722/crispr-in-2018-coming-to-a-human-near-you/