The Antiaging Potential of Electric Stimulation

Dermatologists have known for years that collagen, hyaluronic acid, and elastin decline in concentration with advancing age. Many products have been convincingly shown to increase synthesis of collagen, such as retinoids, vitamin C, and glycolic acid.

However, elastin production is more elusive. Elastin is of particular interest because its loss is responsible for the sagging of the skin with aging, and it also may play a role in the formation of stretch marks. Although I have been unable to find an original reference proving this, many people say that elastin production ceases after puberty. Obviously, increasing collagen and elastin production would be beneficial to the skin's appearance.

Collagen and elastin are made by fibroblasts. These cells play a vital role in wound healing, as they deliver extracellular matrix components that facilitate the migration of other cell types to the wound site (Exp. Dermatol. 2003;12:396-402). This column will briefly discuss some of the research and concepts pertaining to electric stimulation of fibroblasts as a way of promoting the synthesis of collagen and elastin. In fact, the existence and importance of bioelectricity in the human body have been acknowledged for years in relation to wound healing, insofar as electric fields were measured at the sites of human dermal wounds more than 150 years ago, and modern techniques have verified the existence of endogenous electric fields in wounds (Methods Mol. Biol. 2009;571:77-97).

History
Although German physiologist Emil DuBois-Reymond is credited as being the first to identify endogenous electric fields in wounds (based on his paper in 1843 [Ann. Phys. u. Chem. 1843;58:1-30] and his book in 1860 [DuBois-Reymond E. "Untersuchungen uber Thierische Elektricitat, Zweiter Band, Zweite Abtheilung" (Erste Lieferung) Berlin: Georg Reimer; 1860]) and as a founder of modern electrophysiology, several others made key discoveries along the way.
According to a review of bioelectricity by McCaig et al., in the 1700s Italian physician Luigi Galvani, whose surname is the basis for the word "galvanism," witnessed the bioelectric response while dissecting a frog and performing various related experiments (Physiol. Rev. 2005;85:943-78). He termed the phenomenon "animal electricity."

Notably, Italian physicist Alessandro Volta studied the phenomenon and applied its principles to develop the first battery in 1800. Later, in 1831, Italian physicist and neurophysiologist Carlo Matteucci built on Galvani's work by using a galvanometer (named for Galvani, of course) to measure the injury potential of damaged frog muscle (Physiol. Rev. 2005;85:943-78). In the process, Matteucci became the first to demonstrate the action potential in nerves and muscle. DuBois-Reymond subsequently used these findings as the foundation for his considerable contributions revealing injury currents in the skin.
Given the discovery of the formation of an electrical gradient on the skin, its transmission to neighboring cells might be said to make intuitive sense, given how close cells are in relation to one another.

Wound Healing
Contemporary studies continue to shed light on the role of bioelectricity in cutaneous health. Some recent studies also appear to offer potential implications for antiaging therapies.

In 1997, a review by Beech indicated that the migration of cells into wound sites and the stimulation of quiescent cells at the wound margins can be fostered by exogenous, extremely low frequency fields positioned close to the target site, as well as endogenous tissues with enough zeta potential (Bioelectromagnetics 1997;18:341-8).

In 2009, Zhao concluded that electric fields of physiological strength play an overriding role in directing cell migration during epithelial wound healing (Semin. Cell Dev. Biol. 2009;20:674-82). In 2006, Zhao et al. demonstrated experimentally that electric fields, equal in strength to endogenous ones, direct the migration of inflammatory cells, fibroblasts, and epithelial cells in wound healing as the predominant directional signal. In their experiment, the investigators determined that the tumor suppressor phosphatase and tensin homolog (PTEN) and phosphatidylinositol-3-OH kinase-gamma control electrotaxis. They also identified the first genes that influence cellular movement and are necessary for wound healing prompted by electrical signaling (Nature 2006;442:457-60).

More recently, some of the same investigators, including Zhao and McCaig, noted the inherent vectoral nature of electric fields, and again investigated galvanotaxis/electrotaxis or directional cell migration in wound healing. They established several experimental systems, and found that electric fields of potency equal to those identified at in vivo wounds direct cell migration and supersede other guidance cues (e.g., contact inhibition). They concluded that endogenous electric fields may represent significant signaling mechanisms for guiding cellular movement and migration in vivo, and that exogenously applied electric fields may play a clinical role in guiding cell migration in wound healing, with greater versatility than other guidance cues (such as chemical ones) (Methods Mol. Biol. 2009;571:77-97).

In this context, cutaneous wounds are thought to heal as a result of the bioelectrically stimulated dispersal of positively charged ions and proteins to the wound site. Thus, it is believed that exogenously provoking this process that guides physiological activity at the cellular level can hasten wound healing by facilitating the transportation of repairing cells to the wound (Nature 2006;442:457-60).

The review article by McCaig et al., cited above, details the cellular mechanisms responsible for the effects of small electric fields on cell behavior, and considers the clinical potential for electric field treatment of damaged tissues, including epithelia (Physiol. Rev. 2005;85:943-78). The use of a 10-mV charge is key in the development of new products.

Acupuncture
Interestingly, the principles underlying these new products are at least tangentially related to the practice, though not the philosophy, of acupuncture in achieving facial rejuvenation. Traditional Chinese medicine has been shown to be effective for such a purpose. Acupuncture needles are inserted along particular meridians to tonify the skin. Such treatments have ameliorated some wrinkles, improved facial muscle tone, and produced better skin texture while reducing facial edema, acne, and sagging in different locations (Aesthet. Surg. J. 2005;25:419-24).
In traditional Chinese medicine, needle insertion along various meridians is believed to move or rebalance Qi (pronounced "chee"), the life force. The question of what Qi is, remains open to debate, says licensed acupuncturist Lynn Bondi, LAc. "Qi could very well coincide with or even be tantamount to bioelectric fields. But I'm more inclined to think that modern scientific measurement techniques are tapping into or quantifying some portion of Qi, which encompasses much more" (personal communication, Jan. 5, 2010). She notes, interestingly, that modern acupuncturist practice sometimes includes the use of microcurrents for facial rejuvenation.

New Products
Products poised to enter the market soon will be touted for their capacity to harness electrical currents to stimulate fibroblasts into synthesizing collagen and elastin. Several products from Johnson & Johnson - Aveeno, RoC, and Neutrogena - contain zinc and copper in a grayish cream that is applied to the skin. Zinc and copper exchange an electron, purportedly generating a 10-mV charge, which, as stated above, is believed to stimulate fibroblasts into producing collagen and elastin. Application of the grayish cream is followed by use of a moisturizer. The water in the moisturizer in turn activates the "zinc-copper battery," thus creating the charge, which the patient cannot feel. Studies have shown increased elasticity of the skin (as shown by cutometer measurements) when this "zinc-copper battery" is used in combination with a moisturizer containing ingredients that have been shown to increase elastin production and assembly.

The process of stimulating functional elastin production is more complicated than stimulating collagen production. In the body, collagen is extracted from fibroblasts in a complete and final triple-helix form. No further change in structure is necessary for the collagen to be functional. Elastin, however, is secreted by fibroblasts as tropoelastin, which consists of unbound units of elastin in an immature form. Elastin must assemble on a microfibrillin backbone in order to be functional.

According to unpublished proprietary data, one of the new Aveeno products contains blackberry, which stimulates fibroblasts to produce tropoelastin, and dill, which has been shown to aid in assembling the tropoelastin "building blocks" onto a microfibrillin backbone to yield mature elastin. Aveeno has sponsored a study in which cutometer measurements showed increased skin elasticity after use of its Ageless Vitality product for 8-12 weeks.

In essence, the theory behind these new products is that the topical delivery of energized zinc and copper stimulates cutaneous electrical cues that coax the fibroblast to produce collagen and elastin. This process may lead to dermal changes that rejuvenate the skin.

Conclusions
I have not been involved in any of the trials of these products and have no firsthand knowledge of these studies. Conceptually, I am intrigued with the idea of an electromimetic current being used to stimulate fibroblasts. I have reviewed the wound healing literature, and the scientific concepts and data make sense.

The notion of harnessing the natural electric currents of skin cells to increase collagen and elastin production is fascinating for several reasons, not the least of which is elimination of the issue of penetration of active ingredients. A charge generated on the cells in the top layer will likely propagate to neighboring cells, eliminating the need for actual penetration of the zinc and copper.

Consequently, an enhancement of cell-to-cell communication would seem likely to extend to the lower layers, allowing the cells deeper in the dermis to "get the message." These products launch in March, and it will be interesting to see how they are received by dermatologists and consumers.

Dermatologists have known for years that collagen, hyaluronic acid, and elastin decline in concentration with advancing age. Many products have been convincingly shown to increase synthesis of collagen, such as retinoids, vitamin C, and glycolic acid.

However, elastin production is more elusive. Elastin is of particular interest because its loss is responsible for the sagging of the skin with aging, and it also may play a role in the formation of stretch marks. Although I have been unable to find an original reference proving this, many people say that elastin production ceases after puberty. Obviously, increasing collagen and elastin production would be beneficial to the skin's appearance.

Collagen and elastin are made by fibroblasts. These cells play a vital role in wound healing, as they deliver extracellular matrix components that facilitate the migration of other cell types to the wound site (Exp. Dermatol. 2003;12:396-402). This column will briefly discuss some of the research and concepts pertaining to electric stimulation of fibroblasts as a way of promoting the synthesis of collagen and elastin. In fact, the existence and importance of bioelectricity in the human body have been acknowledged for years in relation to wound healing, insofar as electric fields were measured at the sites of human dermal wounds more than 150 years ago, and modern techniques have verified the existence of endogenous electric fields in wounds (Methods Mol. Biol. 2009;571:77-97).

History
Although German physiologist Emil DuBois-Reymond is credited as being the first to identify endogenous electric fields in wounds (based on his paper in 1843 [Ann. Phys. u. Chem. 1843;58:1-30] and his book in 1860 [DuBois-Reymond E. "Untersuchungen uber Thierische Elektricitat, Zweiter Band, Zweite Abtheilung" (Erste Lieferung) Berlin: Georg Reimer; 1860]) and as a founder of modern electrophysiology, several others made key discoveries along the way.
According to a review of bioelectricity by McCaig et al., in the 1700s Italian physician Luigi Galvani, whose surname is the basis for the word "galvanism," witnessed the bioelectric response while dissecting a frog and performing various related experiments (Physiol. Rev. 2005;85:943-78). He termed the phenomenon "animal electricity."

Notably, Italian physicist Alessandro Volta studied the phenomenon and applied its principles to develop the first battery in 1800. Later, in 1831, Italian physicist and neurophysiologist Carlo Matteucci built on Galvani's work by using a galvanometer (named for Galvani, of course) to measure the injury potential of damaged frog muscle (Physiol. Rev. 2005;85:943-78). In the process, Matteucci became the first to demonstrate the action potential in nerves and muscle. DuBois-Reymond subsequently used these findings as the foundation for his considerable contributions revealing injury currents in the skin.
Given the discovery of the formation of an electrical gradient on the skin, its transmission to neighboring cells might be said to make intuitive sense, given how close cells are in relation to one another.

Wound Healing
Contemporary studies continue to shed light on the role of bioelectricity in cutaneous health. Some recent studies also appear to offer potential implications for antiaging therapies.

In 1997, a review by Beech indicated that the migration of cells into wound sites and the stimulation of quiescent cells at the wound margins can be fostered by exogenous, extremely low frequency fields positioned close to the target site, as well as endogenous tissues with enough zeta potential (Bioelectromagnetics 1997;18:341-8).

In 2009, Zhao concluded that electric fields of physiological strength play an overriding role in directing cell migration during epithelial wound healing (Semin. Cell Dev. Biol. 2009;20:674-82). In 2006, Zhao et al. demonstrated experimentally that electric fields, equal in strength to endogenous ones, direct the migration of inflammatory cells, fibroblasts, and epithelial cells in wound healing as the predominant directional signal. In their experiment, the investigators determined that the tumor suppressor phosphatase and tensin homolog (PTEN) and phosphatidylinositol-3-OH kinase-gamma control electrotaxis. They also identified the first genes that influence cellular movement and are necessary for wound healing prompted by electrical signaling (Nature 2006;442:457-60).

More recently, some of the same investigators, including Zhao and McCaig, noted the inherent vectoral nature of electric fields, and again investigated galvanotaxis/electrotaxis or directional cell migration in wound healing. They established several experimental systems, and found that electric fields of potency equal to those identified at in vivo wounds direct cell migration and supersede other guidance cues (e.g., contact inhibition). They concluded that endogenous electric fields may represent significant signaling mechanisms for guiding cellular movement and migration in vivo, and that exogenously applied electric fields may play a clinical role in guiding cell migration in wound healing, with greater versatility than other guidance cues (such as chemical ones) (Methods Mol. Biol. 2009;571:77-97).

In this context, cutaneous wounds are thought to heal as a result of the bioelectrically stimulated dispersal of positively charged ions and proteins to the wound site. Thus, it is believed that exogenously provoking this process that guides physiological activity at the cellular level can hasten wound healing by facilitating the transportation of repairing cells to the wound (Nature 2006;442:457-60).

The review article by McCaig et al., cited above, details the cellular mechanisms responsible for the effects of small electric fields on cell behavior, and considers the clinical potential for electric field treatment of damaged tissues, including epithelia (Physiol. Rev. 2005;85:943-78). The use of a 10-mV charge is key in the development of new products.

Acupuncture
Interestingly, the principles underlying these new products are at least tangentially related to the practice, though not the philosophy, of acupuncture in achieving facial rejuvenation. Traditional Chinese medicine has been shown to be effective for such a purpose. Acupuncture needles are inserted along particular meridians to tonify the skin. Such treatments have ameliorated some wrinkles, improved facial muscle tone, and produced better skin texture while reducing facial edema, acne, and sagging in different locations (Aesthet. Surg. J. 2005;25:419-24).
In traditional Chinese medicine, needle insertion along various meridians is believed to move or rebalance Qi (pronounced "chee"), the life force. The question of what Qi is, remains open to debate, says licensed acupuncturist Lynn Bondi, LAc. "Qi could very well coincide with or even be tantamount to bioelectric fields. But I'm more inclined to think that modern scientific measurement techniques are tapping into or quantifying some portion of Qi, which encompasses much more" (personal communication, Jan. 5, 2010). She notes, interestingly, that modern acupuncturist practice sometimes includes the use of microcurrents for facial rejuvenation.

New Products
Products poised to enter the market soon will be touted for their capacity to harness electrical currents to stimulate fibroblasts into synthesizing collagen and elastin. Several products from Johnson & Johnson - Aveeno, RoC, and Neutrogena - contain zinc and copper in a grayish cream that is applied to the skin. Zinc and copper exchange an electron, purportedly generating a 10-mV charge, which, as stated above, is believed to stimulate fibroblasts into producing collagen and elastin. Application of the grayish cream is followed by use of a moisturizer. The water in the moisturizer in turn activates the "zinc-copper battery," thus creating the charge, which the patient cannot feel. Studies have shown increased elasticity of the skin (as shown by cutometer measurements) when this "zinc-copper battery" is used in combination with a moisturizer containing ingredients that have been shown to increase elastin production and assembly.

The process of stimulating functional elastin production is more complicated than stimulating collagen production. In the body, collagen is extracted from fibroblasts in a complete and final triple-helix form. No further change in structure is necessary for the collagen to be functional. Elastin, however, is secreted by fibroblasts as tropoelastin, which consists of unbound units of elastin in an immature form. Elastin must assemble on a microfibrillin backbone in order to be functional.

According to unpublished proprietary data, one of the new Aveeno products contains blackberry, which stimulates fibroblasts to produce tropoelastin, and dill, which has been shown to aid in assembling the tropoelastin "building blocks" onto a microfibrillin backbone to yield mature elastin. Aveeno has sponsored a study in which cutometer measurements showed increased skin elasticity after use of its Ageless Vitality product for 8-12 weeks.

In essence, the theory behind these new products is that the topical delivery of energized zinc and copper stimulates cutaneous electrical cues that coax the fibroblast to produce collagen and elastin. This process may lead to dermal changes that rejuvenate the skin.

Conclusions
I have not been involved in any of the trials of these products and have no firsthand knowledge of these studies. Conceptually, I am intrigued with the idea of an electromimetic current being used to stimulate fibroblasts. I have reviewed the wound healing literature, and the scientific concepts and data make sense.

The notion of harnessing the natural electric currents of skin cells to increase collagen and elastin production is fascinating for several reasons, not the least of which is elimination of the issue of penetration of active ingredients. A charge generated on the cells in the top layer will likely propagate to neighboring cells, eliminating the need for actual penetration of the zinc and copper.

Consequently, an enhancement of cell-to-cell communication would seem likely to extend to the lower layers, allowing the cells deeper in the dermis to "get the message." These products launch in March, and it will be interesting to see how they are received by dermatologists and consumers.

Dermatologists have known for years that collagen, hyaluronic acid, and elastin decline in concentration with advancing age. Many products have been convincingly shown to increase synthesis of collagen, such as retinoids, vitamin C, and glycolic acid.

However, elastin production is more elusive. Elastin is of particular interest because its loss is responsible for the sagging of the skin with aging, and it also may play a role in the formation of stretch marks. Although I have been unable to find an original reference proving this, many people say that elastin production ceases after puberty. Obviously, increasing collagen and elastin production would be beneficial to the skin's appearance.

Collagen and elastin are made by fibroblasts. These cells play a vital role in wound healing, as they deliver extracellular matrix components that facilitate the migration of other cell types to the wound site (Exp. Dermatol. 2003;12:396-402). This column will briefly discuss some of the research and concepts pertaining to electric stimulation of fibroblasts as a way of promoting the synthesis of collagen and elastin. In fact, the existence and importance of bioelectricity in the human body have been acknowledged for years in relation to wound healing, insofar as electric fields were measured at the sites of human dermal wounds more than 150 years ago, and modern techniques have verified the existence of endogenous electric fields in wounds (Methods Mol. Biol. 2009;571:77-97).

History
Although German physiologist Emil DuBois-Reymond is credited as being the first to identify endogenous electric fields in wounds (based on his paper in 1843 [Ann. Phys. u. Chem. 1843;58:1-30] and his book in 1860 [DuBois-Reymond E. "Untersuchungen uber Thierische Elektricitat, Zweiter Band, Zweite Abtheilung" (Erste Lieferung) Berlin: Georg Reimer; 1860]) and as a founder of modern electrophysiology, several others made key discoveries along the way.
According to a review of bioelectricity by McCaig et al., in the 1700s Italian physician Luigi Galvani, whose surname is the basis for the word "galvanism," witnessed the bioelectric response while dissecting a frog and performing various related experiments (Physiol. Rev. 2005;85:943-78). He termed the phenomenon "animal electricity."

Notably, Italian physicist Alessandro Volta studied the phenomenon and applied its principles to develop the first battery in 1800. Later, in 1831, Italian physicist and neurophysiologist Carlo Matteucci built on Galvani's work by using a galvanometer (named for Galvani, of course) to measure the injury potential of damaged frog muscle (Physiol. Rev. 2005;85:943-78). In the process, Matteucci became the first to demonstrate the action potential in nerves and muscle. DuBois-Reymond subsequently used these findings as the foundation for his considerable contributions revealing injury currents in the skin.
Given the discovery of the formation of an electrical gradient on the skin, its transmission to neighboring cells might be said to make intuitive sense, given how close cells are in relation to one another.

Wound Healing
Contemporary studies continue to shed light on the role of bioelectricity in cutaneous health. Some recent studies also appear to offer potential implications for antiaging therapies.

In 1997, a review by Beech indicated that the migration of cells into wound sites and the stimulation of quiescent cells at the wound margins can be fostered by exogenous, extremely low frequency fields positioned close to the target site, as well as endogenous tissues with enough zeta potential (Bioelectromagnetics 1997;18:341-8).

In 2009, Zhao concluded that electric fields of physiological strength play an overriding role in directing cell migration during epithelial wound healing (Semin. Cell Dev. Biol. 2009;20:674-82). In 2006, Zhao et al. demonstrated experimentally that electric fields, equal in strength to endogenous ones, direct the migration of inflammatory cells, fibroblasts, and epithelial cells in wound healing as the predominant directional signal. In their experiment, the investigators determined that the tumor suppressor phosphatase and tensin homolog (PTEN) and phosphatidylinositol-3-OH kinase-gamma control electrotaxis. They also identified the first genes that influence cellular movement and are necessary for wound healing prompted by electrical signaling (Nature 2006;442:457-60).

More recently, some of the same investigators, including Zhao and McCaig, noted the inherent vectoral nature of electric fields, and again investigated galvanotaxis/electrotaxis or directional cell migration in wound healing. They established several experimental systems, and found that electric fields of potency equal to those identified at in vivo wounds direct cell migration and supersede other guidance cues (e.g., contact inhibition). They concluded that endogenous electric fields may represent significant signaling mechanisms for guiding cellular movement and migration in vivo, and that exogenously applied electric fields may play a clinical role in guiding cell migration in wound healing, with greater versatility than other guidance cues (such as chemical ones) (Methods Mol. Biol. 2009;571:77-97).

In this context, cutaneous wounds are thought to heal as a result of the bioelectrically stimulated dispersal of positively charged ions and proteins to the wound site. Thus, it is believed that exogenously provoking this process that guides physiological activity at the cellular level can hasten wound healing by facilitating the transportation of repairing cells to the wound (Nature 2006;442:457-60).

The review article by McCaig et al., cited above, details the cellular mechanisms responsible for the effects of small electric fields on cell behavior, and considers the clinical potential for electric field treatment of damaged tissues, including epithelia (Physiol. Rev. 2005;85:943-78). The use of a 10-mV charge is key in the development of new products.

Acupuncture
Interestingly, the principles underlying these new products are at least tangentially related to the practice, though not the philosophy, of acupuncture in achieving facial rejuvenation. Traditional Chinese medicine has been shown to be effective for such a purpose. Acupuncture needles are inserted along particular meridians to tonify the skin. Such treatments have ameliorated some wrinkles, improved facial muscle tone, and produced better skin texture while reducing facial edema, acne, and sagging in different locations (Aesthet. Surg. J. 2005;25:419-24).
In traditional Chinese medicine, needle insertion along various meridians is believed to move or rebalance Qi (pronounced "chee"), the life force. The question of what Qi is, remains open to debate, says licensed acupuncturist Lynn Bondi, LAc. "Qi could very well coincide with or even be tantamount to bioelectric fields. But I'm more inclined to think that modern scientific measurement techniques are tapping into or quantifying some portion of Qi, which encompasses much more" (personal communication, Jan. 5, 2010). She notes, interestingly, that modern acupuncturist practice sometimes includes the use of microcurrents for facial rejuvenation.

New Products
Products poised to enter the market soon will be touted for their capacity to harness electrical currents to stimulate fibroblasts into synthesizing collagen and elastin. Several products from Johnson & Johnson - Aveeno, RoC, and Neutrogena - contain zinc and copper in a grayish cream that is applied to the skin. Zinc and copper exchange an electron, purportedly generating a 10-mV charge, which, as stated above, is believed to stimulate fibroblasts into producing collagen and elastin. Application of the grayish cream is followed by use of a moisturizer. The water in the moisturizer in turn activates the "zinc-copper battery," thus creating the charge, which the patient cannot feel. Studies have shown increased elasticity of the skin (as shown by cutometer measurements) when this "zinc-copper battery" is used in combination with a moisturizer containing ingredients that have been shown to increase elastin production and assembly.

The process of stimulating functional elastin production is more complicated than stimulating collagen production. In the body, collagen is extracted from fibroblasts in a complete and final triple-helix form. No further change in structure is necessary for the collagen to be functional. Elastin, however, is secreted by fibroblasts as tropoelastin, which consists of unbound units of elastin in an immature form. Elastin must assemble on a microfibrillin backbone in order to be functional.

According to unpublished proprietary data, one of the new Aveeno products contains blackberry, which stimulates fibroblasts to produce tropoelastin, and dill, which has been shown to aid in assembling the tropoelastin "building blocks" onto a microfibrillin backbone to yield mature elastin. Aveeno has sponsored a study in which cutometer measurements showed increased skin elasticity after use of its Ageless Vitality product for 8-12 weeks.

In essence, the theory behind these new products is that the topical delivery of energized zinc and copper stimulates cutaneous electrical cues that coax the fibroblast to produce collagen and elastin. This process may lead to dermal changes that rejuvenate the skin.

Conclusions
I have not been involved in any of the trials of these products and have no firsthand knowledge of these studies. Conceptually, I am intrigued with the idea of an electromimetic current being used to stimulate fibroblasts. I have reviewed the wound healing literature, and the scientific concepts and data make sense.

The notion of harnessing the natural electric currents of skin cells to increase collagen and elastin production is fascinating for several reasons, not the least of which is elimination of the issue of penetration of active ingredients. A charge generated on the cells in the top layer will likely propagate to neighboring cells, eliminating the need for actual penetration of the zinc and copper.

Consequently, an enhancement of cell-to-cell communication would seem likely to extend to the lower layers, allowing the cells deeper in the dermis to "get the message." These products launch in March, and it will be interesting to see how they are received by dermatologists and consumers.