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CASE STUDY: REJUVENATING IMPACT OF THE SKIN K PROTOCOL ON
FACIAL AGING
Kyze Clauman Goulart1
Abstract: Facial aging is a multifactorial process associated with structural changes, reduced muscle
tone, increased oxidative stress, and the accumulation of cellular metabolic byproducts, such as
lipofuscin, impacting skin rmness, uniformity, and luminosity. In 2018, the author developed an
original injectable protocol, called Skin K, with a patent application led, aiming to promote overall
improvement in skin quality and facial support through cellular and neuromuscular modulation. Since
its implementation in clinical practice, patients undergoing the protocol have been monitored through
comparative clinical evaluation and standardized photographic records. Improvements in tissue
rmness, greater homogeneity of skin tone, and an overall rejuvenating appearance were observed.
The biological mechanisms involved are discussed based on current literature on skin aging. The
ndings suggest that the protocol may represent a promising approach for improving skin quality and
facial support; however, controlled studies are needed for objective validation of the results and in-
depth investigation of the mechanisms involved.
Keywords: Skin K, Skin aging, DMAE (dimethylaminoethanol), Lipofuscin, Oxidative stress, Facial
skin rmness, Injectable treatments, Cholinergic modulation
1 A pharmacist graduated from the University of Southern Santa Catarina (UNESC) in 2004,
with a specialization in Aesthetic Pharmacy from Nepuga Postgraduate Studies (2019), she is a mas-
ter’s student in Health Sciences at UNESC, where she is developing research on the anti-inamma-
tory effects of active ingredients applied to facial rejuvenation protocols focusing on cellular and
muscular modulation.
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INTRODUCTION
Facial aging is a multifactorial biological process characterized by structural and functional
changes that include reduced dermal hydration, decreased muscle tone, increased oxidative stress, and
progressive accumulation of by-products cellular metabolic drugs, such as lipofuscin. The continuous
action of free radicals contributes to cumulative oxidative damage, compromising the integrity of the
extracellular matrix, cellular communication, and skin vitality, resulting in clinical manifestations
such as sagging, opacity, and uneven skin tone.
In 2018, the author developed an injectable protocol called Skin K, which is continuously
applied in clinical practice with the aim of promoting an overall improvement in skin quality and
facial support. The protocol includes as one of the active ingredients the use of injectable DMAE, a
compound associated with the modulation of peripheral cholinergic activity. The literature describes
that acetylcholine plays a central role in muscle contraction and in the regulation of cellular processes,
and can inuence muscle tone and tissue support.
In addition to neuromuscular modulation, mechanisms related to the reduction of oxidative
stress and cellular metabolic dynamics may be associated with improved skin luminosity and
uniformity. Lipofuscin, a pigment resulting from lipid peroxidation and cellular aging, is related to
the progressive darkening of the dermis. The clinical improvement observed after the application
of the protocol is consistent with these mechanisms described in the literature, although no direct
biochemical measurements were performed in this report.
The present study describes the clinical ndings observed using the protocol developed by
the author, discussing its possible biological foundations in the light of current knowledge about skin
aging.
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PERFORMANCE OF THE SKIN K PROTOCOL IN CELL REVITALIZATION AND MUS-
CLE LIFTING: PRELIMINARY CLINICAL REPORT
Image 1
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Image 3
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Image 4
Skin aging is a multifactorial process, in which the accumulation of free radicals and
oxidative stress play a central role in cell degradation, compromising the integrity of the dermis
and epidermis and contributing to visible skin changes, such as loss of rmness, uniformity, and
luminosity (Mustafa, 2024; Ferreira & Matsubara, 1997; Herman, 1992; Braunstein et al., 2025).
A relevant marker of cellular aging is lipofuscin, a residual pigment that accumulates in
lysosomes over time, and is associated with cellular senescence, chronic inammation, and reduced
regenerative capacity of the skin (Baldensperger et al., 2024; Dougnon & Matsui, 2025; Moreno-
García et al., 2018; Renteln, 2024). The reduction or modulation of this accumulation has been
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considered a potential target for interventions aimed at restoring cellular functionality and improving
skin appearance.
In addition to cellular effects, muscle tone also plays an important role in supporting the
skin. The neurotransmitter acetylcholine, produced in skin and muscle tissues, participates in the
regulation of muscle contraction and facial rmness, contributing to the maintenance of the structural
architecture of the face (Kurzen, 2007; Kurzen & Schallreuter, 2004; Slominski et al., 2022).
The Skin K protocol uses a proprietary cosmeceutical formulation composed of active
ingredients with the potential to modulate pathways related to muscle tone and cell metabolism.
Among the compounds described in the literature with this potential, DMAE (dimethylaminoethanol),
a substance associated with the production of choline, a precursor of acetylcholine (Blin et al., 2009),
stands out.
Based on the clinical results observed in this case, and considering scientic evidence related
to the role of DMAE, acetylcholine and lipofuscin in skin aging, it is suggested that the protocol may
act, at the cellular level, modulating aspects associated with muscle tone and the accumulation of
residual pigments, contributing to skin revitalization.
Clinical effects observed include natural-looking facelifting, improved skin tone uniformity,
and increased skin luminosity, conferring a more youthful and revitalized facial appearance, as
demonstrated in comparative clinical photographs before and 15 days after treatment (Figures 1–4).
It should be noted that these ndings are still under investigation, and additional studies are needed
for scientic conrmation. The present clinical report represents a preliminary contribution to the
understanding of the potential mechanism of action of the Skin K protocol in the context of facial
aging.
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COMPARISON BETWEEN THE RESULTS OF SKIN K REJUVENATE AND OTHER
AVAILABLE REJUVENATION TREATMENTS
The comparison between the results of the Skin K protocol and other treatments used in
facial rejuvenation is relevant to contextualize its possible clinical applicability. Currently, several
approaches are employed in aesthetic dermatology, including laser technologies, dermal llers, and
botulinum toxin applications, with the aim of reducing wrinkles, improving facial contour, and
restoring skin quality.
In general, these treatments act through different mechanisms, such as stimulation of
neocollagenesis, volumetric replacement, or modulation of facial muscle activity.
However, in addition to structural changes in the skin, cellular processes associated with
aging, such as oxidative stress and accumulation of waste products of cellular metabolism, also
play a relevant role in the deterioration of skin function (Harman, 1992; Mustafa, 2024; Ferreira &
Matsubara, 1997).
Among these processes, the accumulation of lipofuscin, an intracellular pigment resulting
from lipid peroxidation and incomplete degradation of cellular components, stands out. This pigment
is associated with cellular aging, oxidative stress, and lysosomal dysfunction, and may contribute to
the reduction of the regenerative capacity of tissues (Baldensperger et al., 2024; Moreno-García et al.,
2018; Dougnon & Matsui, 2025).
The understanding of these mechanisms has stimulated the development of therapeutic
approaches that seek not only to improve the external appearance of the skin, but also to act on
cellular pathways related to aging. In this context, the Skin K protocol uses a proprietary cosmeceutical
formulation composed of active ingredients with the potential to act on metabolic pathways associated
with the cellular physiology of the skin.
Among these pathways, the cutaneous cholinergic system stands out. Evidence shows that
human skin has a non-neuronal cholinergic system capable of synthesizing acetylcholine, a molecule
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involved in the regulation of cellular functions and communication between skin cells (Kurzen,
2007; Kurzen & Schallreuter, 2004). Acetylcholine also participates in processes related to muscle
contraction and the structural organization of tissues, and can inuence facial tonicity (Slominski et
al., 2022).
Compounds associated with the choline–acetylcholine pathway, such as dimethylaminoethanol
(DMAE), have been studied for their role as a choline precursor and for their potential biological
effects on different cellular systems (Blin et al., 2009). Thus, approaches that explore these pathways
may represent complementary strategies in the management of the signs of skin aging.
Thus, unlike treatments that act predominantly on structural or volumetric correction of
the face, the proposed protocol seeks to integrate aspects related to cell function and muscle tone.
However, direct comparisons between different therapeutic modalities still require controlled clinical
studies for better evaluation of efcacy and safety.
In addition to objective clinical results, patient satisfaction is a relevant parameter in the
evaluation of aesthetic treatments. Factors such as the naturalness of the result, the perception of
improved skin quality, and the durability of the effects can signicantly inuence the therapeutic
choice.
Thus, the investigation of the Skin K protocol and in the context of facial rejuvenation
can contribute to broadening the understanding of approaches that integrate structural, cellular
and functional aspects of skin aging. Additional studies will be needed to establish more robust
comparisons with other therapeutic modalities used in clinical practice.
SIDE EFFECTS AND CONTRAINDICATIONS OF USING SKIN K REJUVENATES IN DI-
FFERENT SKIN TYPES.
Research into the side effects and contraindications of using the Skin K protocol on different
skin types is essential to ensure the safety and effectiveness of the treatment. While Skin K has shown
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promising results in reducing wrinkles and revitalizing the skin, like any aesthetic intervention, it may
not be suitable for all individuals. Identifying and classifying contraindications is crucial, especially
in populations that are diverse in terms of skin conditions, age groups, and medical history.
Potential side effects can range from mild to moderate, depending on individual skin
sensitivity and the specic characteristics of each patient. Among the effects commonly reported
in injectable treatments are pain at the site of application, ecchymoses, swelling and transient local
reactions. Although serious adverse events are rare, they should be considered in clinical practice. A
detailed evaluation before treatment is essential to minimize risks and ensure patient safety.
Pre-existing skin conditions, such as active dermatitis, eczema, inammatory acne, or open
lesions, may contraindicate the application of the protocol, since the introduction of substances into
compromised tissue can aggravate the condition. Classic evidence indicates that chronic inammation
can alter the response to cutaneous interventions and increase patient discomfort (Manso, 1992;
Harman, 1992). Careful dermatological evaluations and health questionnaires help to identify
contraindications and plan safe alternative strategies.
In addition, individual variability, including genetic and environmental factors, may inuence
treatment response. Each skin type has specic characteristics that can modify both efcacy and
tolerance, and it is important to consider aspects such as phototype, dermal density, and history of
hyperpigmentation or hypopigmentation.
Given the complexity of skin ageing and the variety of treatments available, it is imperative
that the scientic community continues to document and analyze the effects of the Skin K protocol,
considering both objective parameters and the subjective perception of the patient. Ongoing training
of healthcare professionals and maintaining safe application environments are vital to ensuring that
patients receive the best possible care. Continued research on side effects and contraindications will
contribute to a more robust understanding of the protocol, supporting the formulation of practical
guidelines that protect and inform patients.
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FINAL CONSIDERATIONS
The present study describes the development of the injectable Skin K protocol, with the aim
of restoring skin vitality, using active ingredients selected based on their ability to modulate core
processes of skin aging, including oxidative stress, lipofuscin accumulation, and regulation of the
cholinergic pathway.
The preliminary clinical application of the Skin K protocol demonstrated improvement in
luminosity, skin tone uniformity and facial tone, corroborating the hypothesis that the approach based
on the action of these active ingredients can inuence the cellular mechanisms underlying skin aging.
These ndings are in agreement with evidence previously described in the literature on the biological
effects of DMAE and other compounds involved in modulating acetylcholine and maintaining cellular
integrity (Blin et al., 2009; Baldensperger et al., 2024; Kurzen, 2007; Slominski et al., 2022).
The observed clinical results suggest that the Skin K protocol is aligned with the most
relevant biological processes for visible skin aging, providing empirical support for future controlled
investigations. Additional studies will be needed to rigorously quantify the effects, conrm the
molecular mechanisms involved, and establish therapeutic recommendations based on robust scientic
evidence.
Thus, this preliminary report contributes to the understanding of the application of biological
actives in injectable protocols aimed at skin revitalization, offering a solid basis for future research
that integrates clinical observations and cellular mechanisms associated with skin aging.
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