Oxidative stress damages the particularly sensitive hair follicles
Just like all our external skin, the hair and the scalp are exposed to harmful factors every day and these affect the health of the hair more than one would think. While a large number of these factors are of environmental origin, as for example UV light, pollution and chemicals, there are also internal factors including stress or metabolic byproducts. Ultimately, the resulting damage often arises from a common cause: oxidative stress caused by the formation of reactive oxygen species (ROS). It was shown that especially the hair follicles in the scalp are sensitive to oxidative damage, and they require a functional defense system in order to remove ROS and protect the cells from protein and lipid oxidation as well as oxidative DNA damage. The master regulator of the oxidative stress response, nuclear factor erythroid 2-related factor (Nrf2), functions as a switch to activate the synthesis of antioxidant enzymes and to replenish the pool of cellular antioxidants such as glutathione. However, this cellular self-protection system is unable to cope with an excess of detrimental chemical species, and its activity is further known to decline with age. In the scalp in particular, Nrf2 was shown to significantly reduce ROS levels and the associated lipid peroxidation. This prevented the premature transition to the catagen growth regression phase and ultimately ameliorated hair growth inhibition caused by oxidative stress.
A Holy Herb to support the cellular defense system
Mibelle Biochemistry has developed SantEnergy to support the cellular self-protection system, prevent UV-induced oxidative damage and energize the hair follicles. This novel active ingredient is a distinct polyphenol-rich extract based on the wild-crafted aerial parts of Yerba Santa (Eriodictyon californicum), a plant which is also known as Mountain Balm or Holy Herb. A member of the borage family (Boraginaceae), this evergreen aromatic shrub is native to the Pacific Coast of North America, especially California. Its leaves have traditionally been used to treat asthma and other upper respiratory tract infections, and its numerous recorded health benefits include antioxidant, anti-inflammatory, anti-bacterial and neuroprotective activities.
New energy for the hair roots
The beneficial effects of SantEnergy for the hair follicles have been investigated in several in vitro and clinical studies. The active proved to have an energizing effect which is comparable to that of caffeine. An in vitro study showed that the Yerba Santa extract binds to the adenosine receptor in a dose dependent manner. This receptor, which is expressed in various human tissues including the skin, is the molecular target of caffeine and mediates its energizing effect. The active further stimulated the movement of the model organism Caenorhabditis elegans (C. elegans) in a similar manner as pure caffeine, confirming the energizing effect. Moreover, two independent assays showed that SantEnergy has a high antioxidant activity both at the cell membrane and intracellularly, and can thereby protect cells from the harmful influence of oxidizing species. The activity measured in these assays was shown to be in the same order of magnitude as the activity of quercetin, one of the most powerful and well-known natural antioxidants.
Preventing UV-induced oxidative damage in the hair follicle
To further assess the protective effects of SantEnergy, a study was performed on isolated human hair follicles. This model is ideally suited for such investigations in the context of a full mini-organ, to which different stresses can be applied. The results of this study showed that treatment with the active ingredient protected the hair follicles from the oxidative damage caused by repeated irradiation with UVB (20 mJ/cm2). The irradiation caused a significant decrease in active Nrf2 in some of the most sensitive areas of the hair follicle, namely the germinative and pre-cortical hair matrix, as well as the outer root sheath. The treatment with SantEnergy rescued the expression of Nrf2 which allows the hair follicle cells to engage their self-protection system against oxidative stress. In line with this, the UVB irradiation led to a marked increase of 20.5% in 8-hydroxy-2’deoxyguanosine (8-OHdG), a marker of oxidative DNA damage, in the cells located in the dermal papilla of the hair follicles. This could be prevented and even reduced by 3.9% through treatment with the Yerba Santa active compared to untreated, non-irradiated control follicles. As another result of the oxidative damage caused by the UV radiation, an increase in cell apoptosis and a decrease in cell proliferation was observed through TUNEL staining of apoptotic cells and immunofluorescent staining of the proliferation marker Ki67, respectively. Both effects were prevented by the treatment with SantEnergy, which was also reflected by the ability of the active to prevent the premature transition through the catagen regression phase which was induced upon irradiation with UVB in the absence of the active.
SantEnergy improves hair loss and increases hair density
The efficacy of SantEnergy to reduce hair loss was tested in a clinical study involving 56 volunteers (45 women and 11 men; aged 18 to 68 years) who suffered from hair loss. The volunteers were separated into two groups, one of which applied a hair serum containing 2% SantEnergy once daily on the scalp for five months, while the other group used a corresponding placebo product. The results of a cosmetic trichogram analysis showed that the treatment with the active ingredient led to an increase of anagen hair by 31.8%, while the hair in the telogen phase was reduced by 20%. Together, this resulted in an increase of the hair growth coefficient, the anagen to telogen ratio (A/T ratio), by 68%. As the A/T ratio is a direct indicator of the proportion of actively growing hair follicles, it directly impacts on the hair density. Therefore, a measurement with the Trichoscan microcamera was performed and confirmed the trichogram analysis: the hair density increased by 13.1% after five months of treatment with SantEnergy.
Taken together, SantEnergy is an active ingredient with powerful antioxidant properties that energizes the hair follicle cells, supports the cellular self-defense system and thereby protects the hair from oxidative damage and photo-aging. By targeting the hair follicles, the hair protection offered by this novel active starts at the hair root, providing the basis for beautiful hair.