PreprintPDF Available

Niacinamide and Coenzyme Q10: Molecular Insights into Skin Health, Longevity, and Optimized Cosmetic Formulations

Authors:
Preprints and early-stage research may not have been peer reviewed yet.

Abstract

Niacinamide, a derivative of vitamin B3, and coenzyme Q10 (CoQ10), a component of the electron transport chain, are two molecules with potential benefits for skin health and longevity. This comprehensive review discusses the molecular mechanisms through which niacinamide and CoQ10 contribute to maintaining skin cell vitality and combating inflammatory stressors, both on the skin and within the body. Additionally, it highlights the synergy between these two ingredients in cosmetic formulations and potential interactions with other active ingredients. Evidence suggests that niacinamide and CoQ10 can improve skin barrier function, reduce inflammation, promote collagen synthesis, and mitigate the detrimental effects of ultraviolet radiation. These findings emphasize the importance of niacinamide and CoQ10 in supporting skin health, longevity, and their potential in optimized cosmetic formulations.
Advance Research
in Dermatology &
Cosmetics (ARDC)
How to cite this article: Yadav E (2023) Niacinamide and Coenzyme Q10: Molecular Insights into Skin Health, Longevity, and Optimized Cosmetic
Formulations. Adv Res Dermatol Cosmetics 2: 1008
Introduction
Skin health a nd longevity are i nuenced by a combinat ion of intr insic and extr insic factors that contribute to the
accumu lation of molecular and cel lula r damage [1]. Niaci namide, a derivative of vitamin B3, and CoQ10, an e ssential
component of t he mitochondria l electron tra nsport chai n, have emerged as molec ules with pot ential benets f or supporting
skin he alth a nd preventing premature cellular aging [2, 3]. is review explores the molecular me chanisms by which
niacinamide a nd CoQ10 contribute to the ma intenance of skin cell v itality and t he mitigation of in ammatory st ressors on
the skin and within t he body.
Improving Skin Barrier Function
Both niacina mide and C oQ10 have been s hown to enhance sk in barrier fu nction. Niacinamide i ncreases the levels of
key str uctura l proteins, such a s laggri n and involucri n, and promotes th e synthesis of c eramides, c rucial compon ents of the
stratum corneum lipid mat rix [4, 5]. CoQ10 helps maintain the integr ity of cel l membra nes and supports lipid metabolism,
contributing to sk in barrier function [6]. Improved skin barrier func tion resu lts in reduced transepidermal water loss a nd
increased moist ure retention, essential for maintaini ng skin elast icity and resil ience [7].
Reducing Inammation
Inammation i s a critical fac tor in the d ecline of skin f unct ion and appe arance, contr ibuting to the degradation of
extracellu lar mat rix proteins, such as collagen and elasti n [8]. Both niac inam ide and Co Q10 have been repor ted to exer t
anti-inammatory eects. Niacinamide inhibits the production of pro-inammatory cytokines, including interleukin-6
(IL-6) a nd tumor necrosis factor-alpha (TNF-α) [9]. CoQ10 has been shown to modulate t he expre ssion of genes related
to ina mmation and oxidative stress, suc h as NF-κB and Nrf2, prov iding a l ink between Co Q10 and the inammatory
re spo nse [10 ].
Synergy Between Niacinamide and CoQ10 in Cosmetic Formulations
e combinat ion of niacina mide and CoQ10 in co smetic formul ations can oer s ynergist ic benets for sk in health a nd
longevit y. Niacina mide’s ability to improve skin barrier func tion, st imulate collagen synt hesis, a nd reduce inam mation
complements C oQ10’s antioxida nt properties and support of m itochondr ial f unction. is sy nerg y enhances the overall
ecacy of skinc are produc ts conta ining both ingredients, providing a comprehensive approach to sk in health and
aging prevention. Furthermore, combining niacinamide a nd CoQ10 can boost the stability of the se molecu les in topical
formulat ions, ensuring their continued eectiveness over t ime. For ex ample, BABOR is a brand t hat exempl ies such
formulat ions in their sk incare products, oeri ng evidence of the fe asibility and eectiveness of t hese combinations.
Active Ingredients to Avoid Combining with Niacinamide and CoQ10
Althou gh niacina mide and CoQ10 can be sa fely combined wi th various ac tive ingredie nts, there are some i ngredients
to avoid. For example, it is general ly recommended to avoid combining niacinamide w ith high concent rations of alpha-
hydroxy ac ids (AHAs), such as glyc olic acid or lacti c acid, as well as be ta-hydroxy acids (B HAs), like sali cylic acid [11]. ese
exfoli ating acids can potentia lly reduce the eectiveness of niacinam ide by causing pH uctuations i n the formu lation,
altering niacinamide’s stabil ity and e cacy. However, carefu lly designed formulations with t he right pH balance and
bueri ng agents may stil l incorporate these ing redients while m aintaining the bene ts of niacinam ide.
Simi larly, it is advise d not to combine CoQ10 wit h benzoyl perox ide, as benzoy l peroxide has be en reported to deg rade
CoQ10, reducing its antioxidant propert ies [12]. It is essentia l to consider the compat ibilit y of active ingre dients when
formulat ing skincare products to maximiz e the benets and minimize potential adverse reactions.
Volume 2 Issue 1, 2023
Article Information
Received date : April 13, 2023
Published date: April18, 2023
*Corresponding author
Ekta Yadav, Skincare Anarchy LLC, USA
DOI: 10.54026/ARDC/1008
Keywords
Niacinamide; Collagen; Ceramides;
Cytokines
Distributed under Creative Commons
CC-BY 4.0
Mini Review
Niacinamide and Coenzyme Q10:
Molecular Insights into Skin Health,
Longevity, and Optimized Cosmetic
Formulations
Ekta Yadav*
Skincare Anarchy LLC, USA
Abstract
Niacinamide, a derivative of vitamin B3, and coenzyme Q10 (CoQ10), a component of the electron transport chain, are
two molecules with potential benets for skin health and longevity. is comprehensive review discusses the molecular
mechanisms through which niacinamide and CoQ10 contribute to maintaining skin cell vitality and combating inammatory
stressors, both on the skin and within the body. Additionally, it highlights the synergy between these two ingredients in
cosmetic formulations and potential interactions with other active ingredients. Evidence suggests that niacinamide and
CoQ10 can improve skin barrier function, reduce inammation, promote collagen synthesis, and mitigate the detrimental
eects of ultraviolet radiation. ese ndings emphasize the importance of niacinamide and CoQ10 in supporting skin
health, longevity, and their potential in optimized cosmetic formulations.
Page 2/2
Copyright Yadav E
Citation: Yadav E (2023) Niacinamide and Coenzyme Q10: Molecular Insights into Skin Health, Longevity, and Optimized Cosmetic Formulations. Adv Res
Dermatol Cosmetics 2: 1008
Future Directions
Recent adv ances in our u nderstandi ng of the molecu lar mechani sms underlyi ng
the benets of niac inamide and Co Q10 for ski n health have provided valu able insights
into thei r potenti al applications i n skincare products. However, there are st ill s everal
areas t hat war rant further invest igation in order to maximi ze the benets of these
molecules and optimiz e their use in sk incare formulations.
a) Synergistic Eects and Interac tions with Ot her Molecules
b) Future studies shou ld explore potentia l synergistic eects and interactions
between niacinamide , CoQ10, and other molecu les involved in skin healt h and
longevit y [13]. For inst ance, exam ining the combi ned eects of ni acinamide a nd
CoQ10 with ot her antioxidants, such as vitamin C, v itam in E, and resveratrol,
may revea l novel interacti ons that could fu rther enha nce the ecac y of skincare
pr odu cts [14 ].
c) Opti mizing Formulation and Deliver y Systems
d) Research on the opt imal formulation and delivery sy stems for niacina mide and
CoQ10 is crucial for ma ximizing t heir ec acy in s kincare produc ts. Studies
should foc us on identify ing the most suitable car riers, emulsiers, and solvents,
as well a s determini ng the ideal pH and co ncentration for each a ctive ingred ient
[15]. Addit ionally, inves tigating novel de livery syst ems, such as mic roemulsions,
liposome s, and na noparticles, may lead to improved penet ration a nd
bioavai lability of these molecu les in the ski n [16].
e) Long-Term Clinic al Studies
f) Long-term cli nical studie s are nece ssar y to evaluate the safety and ecacy of
niacinamide a nd CoQ10 in sk incare products . ese studies shou ld include
diverse p opulations, d ierent skin t ypes, and va rious environmental cond itions
to ensure a comprehensive u nderstanding of their eects on skin hea lth and
long evit y [17].
Unaddressed Aspects in the Literature
While recent literature has provided valuable insights into t he benets of
niacinamide a nd CoQ10 for ski n healt h, there a re still some cr itica l aspec ts that have
not been thoroughly addres sed.
a) Eects on Skin M icrobiome
b) e skin mic robiome plays a c rucia l role in sk in hea lth and homeostasis.
However, the impact of niac inam ide and Co Q10 on the skin m icrobiome ha s
not been ex tensively studied. Understanding how these molecules interac t
with t he skin’s microbial communit y could prov ide important i nformation for
optimizing t heir use in ski ncare products [18].
c) Epigenetic Reg ulation
d) Epigenetic regulation plays a signi cant role i n aging and skin healt h. Fur ther
studie s should investigate the eects of nia cinamide and CoQ10 on epigenetic
modic ations, such as DNA met hylation and histone acetylation, to better
underst and their roles in skin he alth and longev ity [19].
Conclusion
Niacinamide a nd coenzyme Q10, through th eir multiface ted molecular a ctions,
play signicant roles in maintai ning sk in hea lth and preventing prematu re cellu lar
aging. eir ability to i mprove ski n barr ier function, reduce in ammat ion, promote
collagen synthesis, a nd mitigate the det riment al eects of ult raviolet radiation
highlights t heir importa nce in supporting skin longevit y. e synerg y between
these t wo ingredients i n cosmetic formulations and t he careful con sideration of
active i ngred ients the y can and cannot be combined with en hances their potentia l in
optimized sk inca re product s. Future research should focus on fu rther underst anding
the molecular me chani sms, opt imizing niacinam ide and Co Q10 formulation s,
determ ining optima l concentrations , and investigating potent ial sy nergi stic ee cts
with ot her molecules involved in sk in health and longevit y.
As this comprehensive review has demonstrated , niacinamide a nd coenzyme
Q10 possess sig nicant potent ial for ma intaining skin hea lth and preventi ng
premature cellular aging. With their ability to improve sk in bar rier function, reduce
ina mmation, promote collagen sy nthesis, and mit igate the detri mental eects of
ultraviolet radiation, these molecules are vital for suppor ting skin longevity. By
underst anding the sy nergy b etween these ingredients in cosmetic formu lations
and careful ly considering their interactions with other act ive ingredients, skincare
product developers can opti mize t heir formulation s to ensure t he greatest benets
for skin health . Furt her research in t his are a should foc us on uncovering additiona l
molecular mechanisms, rening niac inam ide and CoQ10 formulations, deter mini ng
ideal concentrat ions, and exploring possible syner gistic eect s with other sk in health-
promoting molecu les.
References
1. López OC, Blasco M A, Partridge L , Serr ano M, Kroemer G (2013) e
hall marks of aging. Cell 153(6): 1194-1217.
2. Wohlrab J, Kre D (2014) Niacinam ide – mecha nisms of action and its topica l
use in dermatolog y. Ski n Pharmacol Physiol 27(6): 311-315.
3. Litta rru GP, Tiano L (20 07) Bioenergetic and a ntioxidant properties of
coenzyme Q10: recent de velopments. Mol Biotech nol 37(1): 31-37.
4. Tanno O, Ota Y, Kita mura N, Katsu be T, Inoue S (2 000) Nicotin amide incre ases
biosynt hesis of ceramides as well a s other st ratum corneum lipids to improve
the epider mal permeabi lity barrier. Br J Dermatol 143(3): 524-531.
5. Gruber J V, Holtz R (2004) Exa mining the impact of sk in lig hteners in vitro.
Cutis 73(2): 19-23.
6. Bentin ger M, Brismar K, D allner G (2007)  e antioxidant ro le of coenzyme Q.
Mitochondr ion 7: 41-50.
7. Levi n J, Momin SB (2010) How much do we really k now about our favorite
cosmeceutical ingred ients? J Clin Aest het Dermatol 3(2): 22-41.
8. Farage M A, Mil ler KW, Elsner P, Maibach HI (2008) Intrinsic and ex tri nsic
factors i n skin ageing: a review. Int J C osmet Sci 30(2): 87-95.
9. Bisset t DL, Oblong JE, Berge CA (2005) Niacinam ide: A B vit amin that
improves ag ing facial sk in appearanc e. Dermatologic Su rgery 31(7): 860-865.
10. Sch melzer C, Lind ner I, Ri mbach G, Ni klowitz P, Menke T, et al. (2008)
Functions of coenzyme Q10 in in amm ation and gene expres sion. BioFactors
32(1-4) : 179-183.
11. Draelos ZD, Ertel KD (2005) Niacina mide-containing facial moisturi zer
improves sk in barrier a nd benets subjects with rosacea. Cutis 76(2): 135-141.
12. Söderberg TA, Sunz el B, Holm S , Elmros T, Hallma ns G, et a l. (1990)
Superoxide anion radical, lipoperoxides and vitamin E in blood from pat ients
with ps oriasis. Arch Dermatol Res 282(5): 298-302.
13. Chaudhuri R K, Bojanowski K (2014) Bakuchiol: A retinol-like fu nctional
compound re vealed by gene expres sion prol ing and c linic ally proven to have
anti-aging eects. I nternational Jou rnal of Cosmetic Science 36(3): 221-230.
14. Pi lki ngton SM, Watson RE, Nicolaou A, R hodes LE (2018) Omega-3
polyunsaturated fatty acids: photoprotec tive macronutrients. Experimental
Dermatology 20(7): 537-543.
15. Ant ille C , Tran C , Sorg O, Saur at JH (2004) Topical beta-c arotene is converted
to retinyl esters i n human skin ex v ivo and mou se ski n in vivo. Ex perimental
Dermatology 13(9): 558-561.
16. Mishra AK, Mishra A, Chattopadhyay P, Kundu PP (2011) Development and
characterization of niosomes for eective transderma l delivery of coen zyme
Q10. Journal of Pharmac y and Pharmacology 63(10): 1332-1340.
17. An JH, K im SY, Lee SA, K im WJ, C hung JH (2015) e eec ts of topical
coenzyme Q10 and vitamin K1 on epiderma l antiox idant status a nd
characteris tics of aged skin: A pilot study. Journa l of Cosmet ic Dermatology
14(2): 117-12 3.
18. Ga llo RL , Nakatsuji T (2011) Microbial symbiosis w ith the innate i mmune
defense system of the skin . Journal of Invest igative Dermatology 131(10): 1974-
1980.
19. Rinner thaler M, Bischof J, Streubel MK, Trost A, R ichter K (2015) Oxid ative
stress i n aging human s kin. Biomolecu les 5(2): 545 -589.
ResearchGate has not been able to resolve any citations for this publication.
Article
Full-text available
Oxidative stress in skin plays a major role in the aging process. This is true for intrinsic aging and even more for extrinsic aging. Although the results are quite different in dermis and epidermis, extrinsic aging is driven to a large extent by oxidative stress caused by UV irradiation. In this review the overall effects of oxidative stress are discussed as well as the sources of ROS including the mitochondrial ETC, peroxisomal and ER localized proteins, the Fenton reaction, and such enzymes as cyclooxygenases, lipoxygenases, xanthine oxidases, and NADPH oxidases. Furthermore, the defense mechanisms against oxidative stress ranging from enzymes like superoxide dismutases, catalases, peroxiredoxins, and GSH peroxidases to organic compounds such as L-ascorbate, alpha-tocopherol, beta-carotene, uric acid, CoQ10, and glutathione are described in more detail. In addition the oxidative stress induced modifications caused to proteins, lipids and DNA are discussed. Finally age-related changes of the skin are also a topic of this review. They include a disruption of the epidermal calcium gradient in old skin with an accompanying change in the composition of the cornified envelope. This modified cornified envelope also leads to an altered anti-oxidative capacity and a reduced barrier function of the epidermis.
Article
Full-text available
The study was undertaken to compare the skin care related activities of retinol and bakuchiol, a potential alternative to retinoids. Retinol is a pivotal regulator of differentiation and growth of developing as well as adult skin. Retinoic acid is the major physiologically active metabolite of retinol regulating gene expression through retinoic acid receptor - dependant and independent pathways. Comparative gene expression profiling of both substances in the EpiDerm FT full thickness skin substitute model was undertaken. Type I, III and IV collagen and aquaporin 3 synthesis in normal human dermal fibroblasts and in were analysed by ELISA and/or histochemistry in EpiDerm FT full thickness skin model were determined. Bakuchiol is a meroterpene phenol abundant in seeds and leaves of the plant Psoralea corylifolia. We present evidence that bakuchiol, having no structural resemblance to retinoids, can function as a functional analogue of retinol. Volcano plots show the great similarity of retinol and bakuchiol gene expression. Retinol-like functionality was further confirmed for the upregulation of types I, and IV collagen in DNA microarray study and also show stimulation of type III collagen in the mature fibroblast model. Bakuchiol was also formulated into a finished skin care product and was tested in clinical case study by twice-a-day facial application. The results showed that, after twelve weeks treatment, significant improvement in lines and wrinkles, pigmentation, elasticity, firmness and overall reduction in photo-damage was observed, without usual retinol therapy-associated undesirable effects. Based on these data, we propose that bakuchiol can function as an anti-aging compound through retinol-like regulation of gene expression. This article is protected by copyright. All rights reserved.
Article
Full-text available
Three cosmetically important skin lightening agents, hydroquinone (HQ), kojic acid (KA), and niacinamide (NA), consume the bulk of successful skin lightening ingredients in cosmetic applications. However, the mechanisms by which these ingredients work are still unclear. In this study, melanocytes and keratinocytes were treated with high, nontoxic doses of HQ, KA, and NA and the cells were examined by human microarrays and protein assays for several important targets including cytotoxicity, melanin expression, tyrosinase gene (TYR) and protein expression, melanocortin-1 receptor (MC1R) gene and protein expression, cytochrome c oxidase-1 (COX1) gene and protein expression, and ferritin (FTH1) gene and protein expression. It was found that all the skin lighteners examined showed marked increases in TYR, COX1, and FTH1 gene and protein expression, but not in MC1R expression in melanocytes. Upregulation of COX1 and FTH1 genes and proteins was common across both cell lines, melanocytes and keratinocytes. The results of the tyrosinase expression were somewhat unexpected. The role of iron in the expression of melanin is somewhat unexplored, but common and strong upregulation of ferritin protein in both types of cells due to the treatments suggests that iron plays a more pivotal role in melanin synthesis than previously anticipated.
Article
Full-text available
Skin protects itself against infection through a variety of mechanisms. Antimicrobial peptides (AMPs) are major contributors to cutaneous innate immunity, and this system, combined with the unique ionic, lipid, and physical barrier of the epidermis, is the first-line defense against invading pathogens. However, recent studies have revealed that our skin's innate immune system is not solely of human origin. Staphylococcus epidermidis, a major constituent of the normal microflora on healthy human skin, acts as a barrier against colonization of potentially pathogenic microbes and against overgrowth of already present opportunistic pathogens. Our resident commensal microbes produce their own AMPs, act to enhance the normal production of AMPs by keratinocytes, and are beneficial to maintaining inflammatory homeostasis by suppressing excess cytokine release after minor epidermal injury. These observations indicate that the normal human skin microflora protects skin by various modes of action, a conclusion supported by many lines of evidence associating diseases such as acne, atopic dermatitis, psoriasis, and rosacea with an imbalance of the microflora even in the absence of classical infection. This review highlights recent observations on the importance of innate immune systems and the relationship with the normal skin microflora to maintain healthy skin.
Article
Full-text available
To date, we are unaware of a review that has investigated common cosmeceutical ingredients in order to answer the three specific questions proposed by the father of cosmeceuticals, Dr. Albert Kligman. It is the goal of this review to gather all the published scientific data on five common cosmeceutical ingredients, answer the three major questions about the scientific rationale for their use, and ascertain how much we really know about consumers' favorite cosmeceutical ingredients.Most of the research concerning cosmeceutical retinoid ingredients is based upon the effects of retinoic acid on the skin. Clinical trials concerning retinol and retinaldehyde are scant and lacking in statistical evaluation for significance. There is research substantiating the effects of kinetin in plants and also in-vitro antioxidant effects. However, proof of anti-aging activity remains elusive, and the clinical efficacy of kinetin is based on limited data. Niacinamide is the ingredient investigated that most closely upholds the "Kligman standards" of cosmeceutical-ingredient analysis. With the available scientific evidence on topical niacinamide, clinicians are able to adequately answer questions about permeability, mechanism, and clinical effect. Both green tea and soy have been popularized commercially based on their antioxidant effects, yet there is a paucity of clinical studies concerning their efficacy as topical anti-aging agents. It may be that soy and green tea are better at preventing the signs and symptoms of skin aging than actually reversing them. Since cosmeceutical products are claiming to therapeutically affect the structure and function of the skin, it is rational and necessary to hold them to specified scientific standards that substantiate efficacy claims.
Article
Niacinamide, an amide of vitamin B3 (niacin), is a hydrophilic endogenous substance. Its effects after epicutaneous application have long been described in the literature. Given a sufficient bioavailability, niacinamide has antipruritic, antimicrobial, vasoactive, photo-protective, sebostatic and lightening effects depending on its concentration. Within a complex metabolic system niacinamide controls the NFκB-mediated transcription of signalling molecules by inhibiting the nuclear poly (ADP-ribose) polymerase-1 (PARP-1). Niacinamide is a well-tolerated and safe substance often used in cosmetics. Clinical data for its therapeutic use in various dermatoses can increasingly be found in the literature. Although the existing data are not sufficient for a scientifically founded evaluation, it can be stated that the use of niacinamide in galenic preparations for epicutaneous application offers most interesting prospects. © 2014 S. Karger AG, Basel.
Article
Aging is characterized by a progressive loss of physiological integrity, leading to impaired function and increased vulnerability to death. This deterioration is the primary risk factor for major human pathologies, including cancer, diabetes, cardiovascular disorders, and neurodegenerative diseases. Aging research has experienced an unprecedented advance over recent years, particularly with the discovery that the rate of aging is controlled, at least to some extent, by genetic pathways and biochemical processes conserved in evolution. This Review enumerates nine tentative hallmarks that represent common denominators of aging in different organisms, with special emphasis on mammalian aging. These hallmarks are: genomic instability, telomere attrition, epigenetic alterations, loss of proteostasis, deregulated nutrient sensing, mitochondrial dysfunction, cellular senescence, stem cell exhaustion, and altered intercellular communication. A major challenge is to dissect the interconnectedness between the candidate hallmarks and their relative contributions to aging, with the final goal of identifying pharmaceutical targets to improve human health during aging, with minimal side effects.
Article
Ultraviolet radiation (UVR) in sunlight has deleterious effects on skin, while behavioural changes have resulted in people gaining more sun exposure. The clinical impact includes a year-on-year increase in skin cancer incidence, and topical sunscreens alone provide an inadequate measure to combat overexposure to UVR. Novel methods of photoprotection are being targeted as additional measures, with growing interest in the potential for systemic photoprotection through naturally sourced nutrients. Omega-3 polyunsaturated fatty acids (n-3 PUFA) are promising candidates, showing potential to protect the skin from UVR injury through a range of mechanisms. In this review, we discuss the biological actions of n-3 PUFA in the context of skin protection from acute and chronic UVR overexposure and describe how emerging new technologies such as nutrigenomics and lipidomics assist our understanding of the contribution of such nutrients to skin health.
Article
Clinical studies demonstrated the efficacy of Coenzyme Q10 (CoQ10) as an adjuvant therapeutic in cardiovascular diseases, mitochondrial myopathies and neurodegenerative diseases. More recently, expression profiling revealed that Coenzyme Q10 (CoQ10) influences the expression of several hundred genes. To unravel the functional connections of these genes, we performed a text mining approach using the Genomatix BiblioSphere. We identified signalling pathways of G-protein coupled receptors, JAK/STAT, and Integrin which contain a number of CoQ10 sensitive genes. Further analysis suggested that IL5, thrombin, vitronectin, vitronectin receptor, and C-reactive protein are regulated by CoQ10 via the transcription factor NFkappaB1. To test this hypothesis, we studied the effect of CoQ10 on the NFkappaB1-dependent pro-inflammatory cytokine TNF-alpha. As a model, we utilized the murine macrophage cell lines RAW264.7 transfected with human apolipoprotein E3 (apoE3, control) or pro-inflammatory apoE4. In the presence of 2.5 microM or 75 microM CoQ10 the LPS-induced TNF-alpha response was significantly reduced to 73.3 +/- 2.8% and 74.7 +/- 8.9% in apoE3 or apoE4 cells, respectively. Therefore, the in silico analysis as well as the cell culture experiments suggested that CoQ10 exerts anti-inflammatory properties via NFkappaB1-dependent gene expression.
Article
Stratum corneum lipids, particularly ceramides, are important components of the epidermal permeability barrier that are decreased in atopic dermatitis and aged skin. We investigated the effects of nicotinamide, one of the B vitamins, on biosynthesis of sphingolipids, including ceramides and other stratum corneum lipids, in cultured normal human keratinocytes, and on the epidermal permeability barrier in vivo. The rate of sphingolipid biosynthesis was measured by the incorporation of [14C]-serine into sphingolipids. When the cells were incubated with 1-30 micromol L-1 nicotinamide for 6 days, the rate of ceramide biosynthesis was increased dose-dependently by 4.1-5. 5-fold on the sixth day compared with control. Nicotinamide also increased the synthesis of glucosylceramide (7.4-fold) and sphingomyelin (3.1-fold) in the same concentration range effective for ceramide synthesis. Furthermore, the activity of serine palmitoyltransferase (SPT), the rate-limiting enzyme in sphingolipid synthesis, was increased in nicotinamide-treated cells. Nicotinamide increased the levels of human LCB1 and LCB2 mRNA, both of which encode subunits of SPT. This suggested that the increase in SPT activity was due to an increase in SPT mRNA. Nicotinamide increased not only ceramide synthesis but also free fatty acid (2.3-fold) and cholesterol synthesis (1.5-fold). Topical application of nicotinamide increased ceramide and free fatty acid levels in the stratum corneum, and decreased transepidermal water loss in dry skin. Nicotinamide improved the permeability barrier by stimulating de novo synthesis of ceramides, with upregulation of SPT and other intercellular lipids.