Making Tears Part 3
For those interested in the relationship between sleep, diet and health (and don’t mind some technical talk), this is a good place to start: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8511346/#:~:text=Tryptophan%20is%20an%20essential%20amino,and%20legumes%20(Table%201).
Getting back to the basics of a tear, this “salad dressing” consists of surface “oils,” a mid-layer of salty water and an inner layer of proteins described as the mucus layer. While each element has specific functions - the primary functions involve transporting oxygen to the surface cells (this is where the salty water plays a critical role) as well as protecting and otherwise supporting them. The oil is a thin “slick” produced by the Meibomian Glands - which are “accordions” in the eyelids and are literally pressed into service by the squeezing pressure of a “good blink.” We will delve deeper into this part of the tear-making discussion later and refocus on the salty water and proteins, here.
If we can use simpler measures of volume to describe a tear (normally measured in microns), then 1-2 “ounces” of the recipe is oil, 7-8 “ounces” is the salty water and as much as 30 “ounces” is the protein “mash” (proteins and sugar complexes suspended in water) we can call mucus. Spread across the surface with a blink, this is the support needed by the “peasant” surface cells and needs to be sustained regardless of the environment (however cold, hot, dry or humid those conditions might be). Treachery in the way of infectious invaders, surface scratches (where a fingernail could be the equivalent of slings and arrows) or siege (the effect of too much staring - so the supply of fresh tears is interrupted and the peasants “go without”) will call on support from within and without the castle walls.
When various messengers (there are many, but include Acetylcholine or ACh and Vasoactive Intestinal Polypeptide or VIP) arrive by way of the major roadways (in our case, nerves and blood vessels), they’re received by their own, external messengers (G-proteins) and make their way to the cell “factories” making the protein products and regulating the transfer of water - largely regulated by Calcium ions (the salty tokens that open these cellular pathways). Other proteins like Immunoglobulins (IgA) are produced by specialized “plasma cells” that can arrive from the gut by way of the blood vessel roadway and can sit amongst the Lacrimal Glands “normal” cells. This appears to be a pathway for the “Gut Associated Lymphoid Tissue” (or “GALT”) to bring immune functions learned from interaction with gut germs to bear on eye protection - but may also open the door to malfunctions leading to autoimmunity (where they become traitorous and inflict damage on normal cells instead of abnormal invaders).
When it comes to fighting germs, protection from “within” comes from a number of “on site” agents. We would get deep into the weeds if I attempt to single out and discuss each one, but there are a few that deserve significant attention here. I’ll begin with Lactoferrin - I see this as an exceptional band of knights who are present in tears and throughout the body - more heavily present in the smooth, moist membranes where germs are likely to first approach us. I’ll refer to this element as “Sir Lact” (yes - lac or lact is derived from the latin word for mik and Lactoferrin is highly present in milk - probably to ensure the offspring being sustained on that milk will have an extra opportunity to fend off infections until they can mount their own vigorous defense system). Sir Lact has the ability to bind iron (so essentially cloaking himself/herself in armor, while denying his foe the same). Iron is critical to bacterial survival and Sir Lact can not only deny them their iron, but also directly damage the membranes of these microbial foes - while signaling other members of our defense system to attack. Interestingly, Sir Lact also helps to control cellular oxidation (think of this as “biological rusting” - and this process of oxidation puts stresses on cells (good or bad) and controlling inflammatory responses - so controlling these processes may help us “age slower,” as well as helping us deal with some of the root causes involved with many neurological diseases (Parkinson’s and Alzheimer’s, to name two), many autoimmune diseases (like Sjogren’s and Rheumatoid Arthritis, to name two more) and cancers (too many to name). Sir Lact appears effective against many bacteria (including some who would be resistant to many of our modern-day antibiotics) and also many viruses. He/She can potentially fend off attackers so we have more time to recognize them and call in specific antibodies and other immune responses that can be more specifically directed to kill those foes. Sir Lact works well with other members of a tear’s defenses, including “Sir Lyse,” (Lysozyme) who will be heavily featured next time.
To schedule an appointment with Dr. Jaccoma, call Excellent Vision at either of these two dry eye offices:
(1) 155 Griffin Rd, Portsmouth, NH 03801 (603) 574-2020
(2) 3 Woodland Rd, STE 112 Stoneham, MA 02180 (near Boston) (781) 321-6463