Backwards retina: retinal controls (Introduction)

by David Turell , Monday, May 22, 2023, 17:30 (551 days ago) @ David Turell

Retinal goes through a toxic phase which is enzyme controlled:

https://www.sciencealert.com/quantum-chemistry-happening-inside-your-eyes-protects-agai...

"Every color, every flash, every sunray exacts a toll on the light-sensitive tissues at the back of our eyes, producing toxic materials that risk damaging the very cells that allow us to see.

"Thankfully, the pigment responsible for darkening our hair, skin, and eyes moonlights as a clean-up crew, mopping up one such dangerous compound before it accumulates into damaging clumps.

***

"Lining the back wall of our eyeball's inner surface is a shag-pile rug of light-reactive cells called the retina. Every fiber in this carpet is packed with pancake-like stacks of discs containing a crucial substance that catches photons of light, starting a chain of reactions that results in a nervous impulse the brain interprets as sight.

"The very first step in this conversion process is a surprisingly dangerous one. The substance, called retinal, contorts into a shape that interferes with the cell's functions, effectively becoming a toxin.

"Evolution has prepared us for this inconvenience, providing enzymes that flip the twisted form of retinal back into a safe and practical shape. What's more, the eye constantly recycles the stacks of discs, dismantling from one end and shuffling fresh light-sensitive packages into place from the other.

***

"Even in individuals with a functional set of enzymes carrying out work as efficiently as possible, a gap in the breakdown process risks another potentially dangerous compound called lipofuscin building up and accumulating into dangerous clumps.

"Again, evolution has an answer, apparently in the form of the dark pigment melanin, which has been seen combining with lipofuscin granules in the retinas of older individuals.

"'It's beginning to look like melanin is nature's solution to a variety of biology's challenges," says Yale therapeutic radiologist Douglas E. Brash.

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"A clue could be found in research revealing lipofuscin breaks apart following the introduction of reagents that produce highly reactive forms of oxygen called radicals.

"On their own, melanin's electrons aren't in a high enough energy state to perform such a task, being blocked by laws of quantum physics that keep them relatively grounded.

"But there is a rather curious loophole. Called chemexcitation, it involves the quantum fine-print of additional materials combining in a way that boosts electrons beyond levels that would typically be prevented, allowing melanin to get a little excited and produce oxygen radicals where needed.

"These quantum chemistry reactions excite a melanin electron to a high energy state and flip its spin, allowing unusual chemistry afterward," says Brash.

***

"Combining high-resolution electron microscopy, genetics, and pharmacology, Brash and his colleagues traced the origins of the melanin and lipofuscin granules and demonstrated melanin's place in the pathway of removing dangerous compounds – but they also showed melanin used its quantum-boosted state to degrade lipofuscin.

"Ideally, the knowledge might be applied to a search for pharmaceuticals that could serve as an alternative to melanin in aging individuals, breaking down lipofuscin before it can cause havoc in retinal tissues.

"'For 30 years I was convinced that melanosomes – the organelles in cells that create melanin – degrade the lipofuscin, but couldn't identify a mechanism," says the study's senior author Ulrich Schraermeyer, an experimental ophthalmologist at the University of Tübingen.

"'Chemiexcitation is the missing link, and it should let us bypass the problem that AMD begins when the eye's melanin declines with age. A drug that is chemiexcited directly may be a breakthrough for our patients."

Comment: once again the backwards retina is designed to perfection. This is a perfect example of an irreducibly complex set of reactions in which a toxic material must be produced and at the same time neutralized. Natural evolution cannot produce two opposites at the same time. Requires design.