About Hyaluronic Acid (sodium hyaluronate powder) in DIY Skin Care
The epidermis is the outer layer of the skin which serves to protect the body from water loss and from the environment. Immediately beneath the epidermis is a matrix comprised of structural elements collagen and fibrin which provide the basic support for the matrix. Hyaluronic acid fills in this structured system to provide insulation to the matrix and to maintain mechanical integrity. HA is a polymer composed of long chains of non-sulfated glycosaminoglycans and is produced by dermal fibroblasts. In a complicated feedback loop HA regulates dermal fibroblast proliferation and migration, stimulating its own production or degradation depending on the stimuli present [1, 2]. HA is also capable of initiating these and other important cellular signaling pathways depending on the size of molecular weight HA present. Because HA is made of linked glycosaminoglycans, it can be considered high or low, comparatively, in molecular weight with masses ranging from 20 to over 4,000 kDa. Interestingly, the high and low molecular weight HA species can have opposing effects. High molecular weight HA signals that the integrity of the extracellular matrix is maintained and everything is status quo, whereas very low molecular weight HA [20 kDa and below] signals matrix damage and initiates a proinflammatory response. Thus, in order to avoid increasing inflammation in the skin low or high molecular weight HA [50 kDa and greater] is generally preferred [3, 4].
While collagen and fibrin provide the general structure and organization for the skin, HA is what fills in the remaining space and gives healthy skin the ideal supple and elastic feel and smoothes out fine lines or wrinkles. On the other hand, degradation of HA, resulting from wound or aging, is what leads to the appearance of fine lines and wrinkles. HA is capable of binding massive amounts of water. In fact, it’s water-binding capacity is greater than any other natural or synthetic polymer [5], a property which makes it attractive for use in topical applications to increase hydration of the skin, in anti-aging cosmetic creams, and to provide wound healing support [6, 7]. However, to most efficiently perform the desired function the choice of molecular weight HA for use should be made with care. To best moisturize the skin and reduce the appearance of aging, HA must be able to penetrate through the epidermis. Studies have demonstrated that in order to penetrate the thick outer layer of skin molecular weight HA species that are considered low, but not low enough to stimulate inflammation, are ideal [7].
50 kDa HA species have been demonstrated to most efficiently penetrate the skin in comparison to 300, 800, and 1,500 kDa species. In human volunteers, topical solutions containing 50 kDa significantly decreased the roughness of the skin whereas 300 kDa HA had no effect. Further, the appearance of wrinkles in these subjects was markedly decreased [8]. It is also known that high molecular weight HA can stimulate activation of approximately 40 genes in keratinocytes which are related to regulation of dermal cells and the formation of cell-cell tight junctions, on intercellular bridges. A recent study demonstrated that low molecular weight HA is not only capable of activating all of these genes but also affects the expression of 80 more genes all of which are related to improved skin appearance, function, and structure. The increase is believed to be directly related to the ability of low molecular weight HA to more efficiently penetrate the epidermis [4, 8]. Considering these results, for use in moisturizers and anti-aging cream low molecular weight cream is the optimal choice.
For additional information, please refer to our link here: Low Molecular Weight (50kDa) Hyaluronic Acid
While low molecular weight HA is certainly most ideal for moisturizing and anti-aging cosmetics, high molecular weight HA remains the conventionally utilized species. High molecular weight species forms lightweight gels that, when combined with an emulsifier and oil can form a serum which can limit water evaporation from the skin. This not only improves the feel of the epidermis but also supports the function of the epidermal barrier, causing skin to feel protected and healthier [9]. Other studies have demonstrated that such gels when applied to dermal wounds can expedite wound healing [10, 11]. A recent in vivo study demonstrated that HA gels applied topically to chemically-induced wounds on the skin of rats were successfully able to increase the rate of wound closure. Further, HA stimulated fibroblast migration to the site of the wound, leading to increased collagen regeneration and rates of re-epithelialization [11].
Hyaluronic acid in dry climates
"there is a controversy whether concentrated HA formulas should be used as a moisturizer in dry climate. When air humidity is very low, HA may preferentially pull water from the skin rather than from the air, thus producing the opposite effect." [
Dr. G. Todorov. Hyaluronic acid for skin hydration and possibly a lot more.1999-2015. SmartSkinCare.com]
To properly use a hyaluronic acid serum, it needs to be applied onto damp skin and then "sealed" in with a layer of a good moisturizer on top. If applying the hyaluronic acid in this manner still makes your skin feel a bit dry or taut, the hyaluronic acid is probably pulling moisture out of your skin instead of pulling moisture from the air and into your skin.
Note that the combination of Niacinamide and Glucosamine has been proven to actually increase Hyaluronic acid synthesis in the skin, thereby moisturizing from the inside, rather than putting moisture on top of the skin.
For further detailed and unbiased information about topical Hyaluronic acid in skin care we suggest you read these two excellent articles by Dr. Todorov from smartskincare.com
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Hyaluronic acid: Skin matrix health is not just about proteins and
Hyaluronic acid for skin hydration and possibly a lot more
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[2] Price RD, Berry M, Navsaria HA. Hyaluronic acid: the scientific and clinical evidence. Journal of Plastic, Reconstructive & Aesthetic Surgery. 2007;60[10]:1110-9.
[3] Gariboldi S, Palazzo M, Zanobbio L, Selleri S, Sommariva M, Sfondrini L, et al. Low molecular weight hyaluronic acid increases the self-defense of skin epithelium by induction of β-defensin 2 via TLR2 and TLR4. The Journal of Immunology. 2008;181[3]:2103-10.
[4] Farwick M, Gauglitz G, Pavicic T, Köhler T, Wegmann M, Schwach-Abdellaoui K, et al. Fifty-kDa hyaluronic acid upregulates some epidermal genes without changing TNF-α expression in reconstituted epidermis. Skin pharmacology and physiology. 2011;24[4]:210-7.
[5] Becker LC, Bergfeld WF, Belsito DV, Klaassen CD, Marks JG, Shank RC, et al. Final report of the safety assessment of hyaluronic acid, potassium hyaluronate, and sodium hyaluronate. International journal of toxicology. 2009;28[4 suppl]:5-67.
[6] Weindl G, Schaller M, Schafer-Korting M, Korting H. Hyaluronic acid in the treatment and prevention of skin diseases: molecular biological, pharmaceutical and clinical aspects. Skin Pharmacology and Physiology. 2004;17[5]:207-13.
[7] Brown TJ, Alcorn D, Fraser JRE. Absorption of hyaluronan applied to the surface of intact skin. Journal of investigative dermatology. 1999;113[5]:740-6.
[8] Farwick M, Lersch P, Strutz G. Low molecular weight hyaluronic acid: its effects on epidermal gene expression & skin ageing. SÖFW Journal. 2008;134[11]:17.
[9] Draelos ZD. New treatments for restoring impaired epidermal barrier permeability: skin barrier repair creams. Clinics in dermatology. 2012;30[3]:345-8.
[10] Price RD, Das-Gupta V, Leigh IM, Navsaria HA. A comparison of tissue-engineered hyaluronic acid dermal matrices in a human wound model. Tissue engineering. 2006;12[10]:2985-95.
[11] Al Bayaty F, Abdulla M, Hassan MA, Masud M. Wound healing potential by hyaluronate gel in streptozotocin-induced diabetic rats. Scientific Research and Essays. 2010;5[18]:2756-60.