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All about the remarkable compound Greyverse in remarkable RevivHair REV with Grey Hair Reverse + Hair Stimulation (product page here):
A breakthrough innovation from Lucas Meyer Cosmetics, Greyverse™ is the first anti-grey hair biomimetic peptide. Clinically effective, it helps men and women suffering from greying hair look naturally younger by reversing the hair aging process and increase their self-esteem.
Greyverse™ is the result of a wide screening of several peptides tested on different biological targets involved in the hair greying process. Greyverse™ is a patented Palmitoyl Tetrapeptide (4 amino acids grafted on palmitic acid). The active sequence is derived from the α-MSH structure, known to be the main molecule able to stimulate melanogenesis. As an analogue of α-MSH, Greyverse™ is able to bind to MC1-R (Melanocortin-1 Receptor), a transmembrane receptor located at the surface of melanocytes. The activation of MC1-R stimulates the melanogenesis process, as well as the catalase expression and activity.
Due to its complete mechanism of action, Greyverse™ is able to act simultaneously and efficiently on the two main factors causing hair greying process:
- It stimulates melanogenesis to increase melanin production in the bulb and favor a better transfer leading to hair repigmentation.
- It lowers oxidative stress by increasing the catalase expression and activity, thus reducing the accumulation of hydrogen peroxide to maintain the full pigment color.
Contrary to skin melanocytes, which are able to produce a higher quantity of melanin than the constitutive skin color if they are stimulated (facultative pigmentation), hair melanocytes cannot produce more than they are genetically programmed (constitutive pigmentation only). Thus, Greyverse™ can only help hair recover its natural color, it cannot darken it.
IN VITRO EFFECT OF GREYVERSE™ ON MELANIN SYNTHESIS IN HUMAN MELANOCYTES
Hair pigmentation is due to the presence of a pigment, melanin, secreted by the melanocytes located in the hair bulb and then transferred into the surrounding keratinocytes . The appearance of greying hair is a phenomenon directly linked to a lack of melanin in the hair bulb.
This study investigated Greyverse™ activity by measuring its effects on the production of melanin in a human melanocyte culture.
The melanocytes used were a cell line of primary normal human epidermal melanocytes from adult tissue (HEMas). HEMas cells were grown in an adherent cell culture realized with CnT-40 CellnTec medium at 37°C, 5% CO2 and 95% humidity.
- The Palmitoyl Tetrapeptide-20 (pure peptide contained in Greyverse™) was tested at the following concentration: 10-7M (equivalent to 0.5% Greyverse™).
- The positive control, α-MSH, was tested at a concentration of 10-6 M.
Evaluation of the activity
HEMas cells were seeded in 6-well plates at the concentration of 3.105 cells/mL in a CnT-40 culture medium and incubated at 37°C, 5% CO2. After 24 hours, the medium was removed and the cells were treated with Palmitoyl Tetrapeptide-20 (10-7M) or α-MSH (10-6M) for 72 hours. After 72 hours of treatment, cells were detached for counting, then incubated at 100°C for 10 minutes with NaOH at 1M to extract melanin.
Then, melanin was detected by absorbance at 405 nm. Melanin content was expressed as the percentage of melanin production, compared to cell numbers.
After 72h of treatment, Greyverse™ significantly increased the melanin synthesis by 19% at the concentration of 10-7 M. The results indicate that Greyverse™ has an activity stronger than the positive control α-MSH.
A biomimetic peptide of α-MSH, Greyverse™ stimulates the melanin synthesis to improve grey hair repigmentation.
EX VIVO EFFECT OF GREYVERSE™ ON PIGMENTATION IN HUMAN HAIR FOLLICLES
Melanosomes are typically divided into four maturation stages (I–IV) determined by their structure and the quantity, quality, and arrangement of the melanin produced.
- Stage I melanosomes have an early matrix organization, are spherical, do not contain tyrosinase activity, and are localized at the periphery of the nucleus.
- Stage II melanosomes are tyrosinase-containing elongated organelles with an organized filamentous matrix. In addition, Mart-1 protein, also known as Melan-A, localized in stage I and/or II, contributes to the melanosome formation.
- Stage III melanosomes, where melanin is uniformly deposited.
- Stage IV melanosomes are melanosomes that are electron-opaque, fully melanized and have a low tyrosinase activity; they are the melanosomes supplied from the dendrites to the neighbouring keratinocytes.
Within melanosomes, at least three key enzymes, tyrosinase, Tyrosinase-related protein 1 (TRP-1), and Tyrosinase-related protein 2 (TRP-2), are absolutely required for the synthesis of different types of melanin. Moreover, the quality of the pigment depends of the balance of the Agouti signaling protein (ASIP, also known as PARD3) and alpha-MSH expression. The binding of ASIP to MC1R precludes alpha-MSH initiated signaling and thus blocks production of cAMP, leading to a down regulation of eumelanogenesis (brown/black pigment) and increasing synthesis of pheomelanin (yellow/red pigment).
The aim of this study was to determine the effects of Greyverse™ on the pigmentation of isolated human grey hair follicles. To this end, we checked the hair melanosome biogenesis by melanosomal protein immunohistochemistry (Melan-A and TRP-1) and by the nature of the pigment expressed by the immunostaining of ASIP/PARD3.
Palmitoyl Tetrapeptide-20 (pure peptide containing in Greyverse™) was tested at the concentrations of 10-9 M and 10-7 M, equivalent to 0.005% and 0.5% Greyverse™, respectively.
On a scalp plasty coming from a 71-year-old Caucasian woman who originally had dark hair, grey hair follicles (from the infundibulum to the bulb) were isolated by micro dissection on day 0 (D0). These hair follicles were placed separately in a 48-well plate and kept in survival for seven days in William’s medium (Sigma-Aldrich, W1878) supplemented with Lglutamine, insulin, hydrocortisone, serum and antibiotics, at 37°C in a 5% CO2 atmosphere. Eleven hair follicles were used per condition (untreated or treated). The Palmitoyl Tetrapeptide-20 was diluted in the culture medium on day 0, day 1, day 4 and day 7 whereas the untreated medium was renewed.
At the end of survival (day 7), the hair shafts were fixed in buffered formalin solution, dehydrated, and paraffin impregnated. 7-µm-thick paraffin sections were mounted on glass slides for immunostainings and stainings.
- For fluorescent immunostainings, the primary antibodies used were anti-PARD3/ASIP (Abcam, ref. ab64646). The sections were then incubated for 30 minutes at room temperature with the Alexa Fluor 488-labeled antibody (Lifetechnologies, ref. A11078). The nuclei were counter-stained using propidium iodide at 0.2µg/mL. The slides were finally mounted using Vectashield® mounting medium (Vector, ref. H-1400).
- For Immunohistochemistry, the hair sections were pre-incubated with hydrogen peroxide (VWR, ref. 23619.264) to inactivate endogenous peroxidase activity. The primary antibodies used were anti-TRP1 (Eurogentec, ref. SIG-38150-1000) and anti-Melan-A (Santa Cruz biotechnologies, ref. sc-20032). Then, the sections were pre-incubated with a biotinylated secondary antibody and incubated with a streptavidin-labeled peroxidase (Vector, Vectastain® Universal ABC kit, ref. PK7200). The staining was revealed by a substrate of peroxidase, VIP (Vector, ref. SK-4600). The nuclei were counter-stained using Mayer hemalun (RAL diagnostics, ref. 320550). The slides were finally mounted using Eukitt mounting medium (VWR, ref. KIND01250).
The microscopic observations were performed using a Leica DMLB or Olympus BX43 microscope. Pictures were digitized with a numeric DP72 Olympus camera with CellD storing software. Different hair parts were analyzed: the infundibulum, upper shaft, bulge, lower shaft and bulb.
After 7 days of treatments with 10-9 M and 10-7 M Palmitoyl Tetrapeptide-20, the expression of the melanosome protein, Melan-A, was increased especially in the upper sheath and in the bulb area, a site of melanocyte stem cells, attesting an improvement in the melanosome maturation, necessary for an optimal transfer.
Moreover, the expression of the Agouti signaling protein, ASIP/PARD3, was decreased in the lower part of the hair follicle (lower root sheath and bulb). This result indicates that Greyverse™ directs the nature of pigment synthesis: it preferentially increases eumelanin synthesis over pheomelanin synthesis, allowing the natural dark hair color of the donor to be recovered.
The key enzyme of melanin synthesis, tyrosinase-related proteins 1 (TRP1), was induced in the upper root sheaths, attesting the greater capacity to produce pigments.
Greyverse™ promotes hair pigmentation by increasing melanosome transfer and melanin synthesis, preferably eumelanin.
IN VITRO EFFECT OF GREYVERSE™ ON MELANOSOME TRANSFER IN A CO-CULTURE OF KERATINOCYTES AND MELANOCYTES
Hair pigmentation can be influenced by the concentration of melanin as well as by the number, size and distribution of melanosomes around the nucleus of keratinocytes. Melanin is synthesized, stored and transported within a specialized organelle called a melanosome in melanocyte. The transfer of melanin from melanocytes to keratinocytes (melanosome transfer + phagocytosis) is a critical step in skin pigmentation, one that depends on various parameters such as melanocyte dendricity.
n this study, the potential pro-pigmenting effect of Greyverse™ was evaluated in a co-culture of normal human epidermal keratinocytes (NHEK) and normal epidermal melanocytes (NHEM). In brief, the effect of Greyverse™on melanosome transfer was evaluated using flow cytometry to quantify a melanosome specific marker (Pmel17) inside keratinocytes identified by the expression of the cell surface marker CD49f.
- Palmitoyl tetrapeptide-20 (pure peptide contained in Greyverse™) was tested at the concentration of 10-9M (equivalent to 0.005% Greyverse™)
- Positive reference: stimulation mix containing pro-pigmenting factors prepared in accordance with the internal protocol of Bioalternatives (Gençay, France).
The human keratinocytes and human melanocytes were seeded (10:1 ratio) in 24-well plates in a co-culture medium and incubated for 48 hours, with a medium renewal after 24 hours. The medium was then removed and replaced by a co-culture medium containing or not containing the active compound or the positive reference. The cells were then incubated for 48 hours. Half of the medium was then discarded, the treatments were renewed and the cells were incubated for 72 hours. All experimental conditions were performed in n=4.
Labelling and cytometry analysis
At the end of the incubation period, the medium was removed and cells were rinsed with a PBS solution. Cells were then detached using a trypsin treatment and transferred to tubes. After several washes in PBS/BSA 0.2% cells were fixed, permeabilized and labeled with the antibodies below:
- Anti-CD49f-FITC: CD49f corresponding to integrin α6 specific to keratinocytes
- Anti-Pmel17 (specific to melanocytes and melanosomes). Anti-Pmel17 labeling was revealed using a conjugated allophycocyanin (GAM-APC) secondary antibody
- Or both.
Acquisitions were performed on 10,000 cells for each replicate, after selection of a homogeneous population analyzed for size (FSC) and granularity (SSC) parameters by flow cytometry using a BD FACSVerse™ flow cytometer. Data analysis was carried out using FlowJo vX software. The melanosome transfer evaluation was performed by quantifying the double-labeled keratinocyte population for CD49f and Pmel17 and calculating the percentage of variation compared to the untreated control.
The inter-group comparisons were performed using an Unpaired Student’s t-Test: *p<0.05, **p<0.01 and ***p<0.001.
After 72 hours of treatment, Greyverse™ significantly increased the melanosome transfer between melanocyte and keratinocyte cells by 50%.
Greyverse™ stimulates melanosome transfer, thus increasing melanin content in the hair shaft and leading to natural hair pigmentation recovery.
EX VIVO EFFECT OF GREYVERSE™ON MACROSCOPIC PIGMENTATION IN ISOLATED HUMAN HAIR FOLLICLES
To complete the previous data, the aim of this study was to evaluate the activity of Greyverse™ on the macroscopic hair pigmentation of isolated hair follicles maintained in survival.
Palmitoyl Tetrapeptide-20 (pure peptide contained in Greyverse™) was tested at the concentrations of 10-9M and 10-7M, equivalent to 0.005% and 0.5% Greyverse™, respectively.
On a scalp plasty coming from a 76-year-old woman, 74 inferior hair follicles (lower root sheath and bulb) were isolated by microdissection. These hair follicles were placed in 48-well plates and kept in survival for 8 days at 37°C in a 5% CO2 atmosphere, in a Philpott medium composed of William’s medium (ref. W1878, SigmaAldrich) supplemented with L-Glutamine, insulin-transferrin-selenium, hydrocortisone, penicillin/streptomycin antibiotics and serum (300 μl per well).
The entire culture medium was renewed (300 μl per well) on day 0, day 1, day 4 and day 6 and the products to be tested were added to it. The untreated batch did not receive any treatment other than the renewal of the medium.
Hair follicle pigmentation analyses
Microscopic observation of grey hair follicle pigmentation:
The method consisted in mounting selected hairs on clear glass slides for microscopic observation (hairs were then fixed)
- Hair pigmentation on mounted hairs
Selected hair follicles were fixed and mounted on clear glass slides using a Clarine-Eukitt mounting medium to visualize the hair pigmentation by microscopic observation. The microscopic observations were performed using a Leica DMLB or Olympus BX43 microscope. Pictures were digitized with a numeric DP72 Olympus camera with CellD storing software.
All image processing was performed with Fiji software . The first part of the processing allowed the hair follicle to be extracted from the rest of the image and its surface measured (in mm²). The “subtract background” function was used to remove smooth continuous backgrounds from the image. Then, the image intensities were enhanced using the Enhanced Local Contrast (CLAHE) plugin. This filter allows the local contrast in an image to be equalized (it reduces inhomogeneity in terms of intensity), while preserving the selected regions of interest and limiting the amplification of noise. This method helped increase hair detection. Finally, an automatic threshold level was set to create the corresponding binary image of the hair, and calculate area statistics (hair surface in mm²).
In the second part of the processing, an automatic thresholding was used on each raw image in order to select pixels corresponding to the pigmented area only. Using binary images of the selected hair (first part of the pipe) as an inclusive mask, the surface of these pigments (in mm²) was computed in the hair area only.
The inter-group comparisons were performed by an Unpaired Student’s t-Test: *p<0.05, **p<0.01 and ***p<0.001.
The micro-dissected hair follicles were put in survival and photographed alive (20 hairs per batch) on day 0 (before treatment) and day 8 (after treatment). The evolution of the hair bulb pigmentation was estimated by image quantification on day 8 compared to day 0, for each isolated hair follicle. The results were expressed as a percentage of variation of area hairs exhibiting an increase in hair pigmentation.
According to the experimental conditions, after 8 days of survival and compared to day 0, the Palmitoyl Tetrapeptide-20 Fgrey increased hair pigmentation by 52% and 66% at concentrations of 10-9 M and 10-7M, respectively.
The color of the treated hair follicles had increased, attesting a higher melanin content.
Greyverse™ visibly darkens hair by increasing the melanin content in the hair shaft.
IN TUBO EFFECT OF GREYVERSE™ ON CATALASE ENZYMATIC ACTIVITY
Recently, Shi and al.  have shown that a deficiency of catalase, an enzyme that allows the transformation of hydrogen peroxide into oxygen and water (2 H2O2 → 2 H2O + O2) in human hair follicles, largely contributes to the greying of hair. Moreover, it was shown that it induces a change in the conformation of the tyrosinase structure synthesized by hair follicle melanocytes, especially by the oxidation of the methionine residues of this key enzyme in melanin production. This structural modification of the tyrosinase leads to a loss of its enzymatic activity and stops melanin synthesis in the melanocytes of the hair follicle.
The aim of this study was to determine the direct effect of Greyverse™ on catalase activity by measuring the quantity of H202 not degraded by the enzyme.
Palmitoyl Tetrapeptide-20 was tested at the concentration of 10-5 M.
The catalase activity was evaluated using the Amplex® Red Catalase Assay Kit purchased by Molecular Probes (Invitrogen, ref: A22180) in compliance with the instructions of the manufacturer. In the assay, catalase first reacts with H2O2 to produce water (H20) and oxygen (O2). Then, the Amplex Red reagent reacts with a 1:1 stoichiometry with any unreacted H2O2 in the presence of horseradish (HRP) to produce the highly fluorescent oxidation product, resorufin. A correlation with catalase activity is then calculated.
A 10-5 M Palmitoyl Tetrapeptide-20 solution was incubated with 6.25 mU catalase in a 96-well plate for 10 minutes at room temperature. Then, an extemporaneously prepared solution of H2O2 (20 µM final concentration) was added and the mixture was incubated for 30 minutes at room temperature in the dark. A mixture of HRP (0.2U/mL final concentration) and Amplex Red fluorogenic probe (50 µM final concentration) was then added and the plates were incubated in the dark at 37°C for 60 minutes.
Evaluation of the activity
The generated fluorescence of formed resorufin was immediately recorded (λex = 544nm, λem = 590 nm) using a Polar Star Omega (BMG, Ortenberg, Germany) reader.
The inter-group comparisons were performed by an Unpaired Student’s t-Test: #p<0.1, *p<0.05, **p<0.01 and ***p<0.001.
The Palmitoyl Tetrapeptide-20 is able to significantly increase, in tubo, catalase activity by 7.5%.
Greyverse™ improves catalase activity to reduce the greying hair process due to oxidative stress caused by excess H202.
IN VITRO EFFECT OF GREYVERSE™ ON THE INTRACELLULAR H2O2 LEVEL IN HAIR FOLLICLE DERMAL PAPILLA FIBROBLASTS
Recently, Shi and al. have shown that a deficiency of catalase, an enzyme that allows the transformation of hydrogen peroxide into oxygen and water (2 H2O2 → 2 H2O + O2) in human hair follicles, largely contributes to the greying of hair.
The aim of this study was to determine the effect of Greyverse™ on the intracellular H2O2 level due to its action on the increased catalase activity.
- Palmitoyl Tetrapeptide-20 was tested at the concentration of 10-5 M.
- The 2’,7’-Dichlorofluorescein diacetate (DCFH-DA) was used at a final concentration of 10 µM.
HFDP cells are fibroblasts isolated from human hair dermal papilla and maintained in a specific follicle dermal papilla cell medium (Promocell, Ref: C-26501) containing fetal serum (0.04 mL/mL), bovine pituitary extract (0.004 mL/mL), basic fibroblast growth factors (recombinant human, 1 ng/mL), insulin (recombinant human, 5µg/mL) and antibiotics (penicillin/streptomycin/Eurobio, CABPES01-OU) at 37 °C under 5% CO2 and 95% humidity.
The intracellular levels of H2O2 were evaluated by using a fluorescent dichlorofluorescein assay adapted to flow cytometry which allowed the detection of picomole levels of hydroperoxides . Using the fluorogenic probe and the 2’,7’-Dichlorofluorescein diacetate (DCFH-DA) (Sigma, Ref: D6883), we assessed the levels of intracellular hydrogen peroxide within the untreated control and the treated cells. HFDPC cells were seeded at 2.106 cells/well in 12-well plates with 500 µl complete medium and incubated for 24 hours at 37°C. Palmitoyl Tetrapeptide-20 (10-5 M) was then added and incubated for 18 hours at 37°C. At the end of incubation, DCFH-DA probe (10 µM final concentration) was added for an additional 15 minutes.
Evaluation of the activity
Cells were then trypsinized, washed and immediately scanned on an FACS (FC500 flow cytometer, BeckmanCoulter) with excitation and emission settings of 485 nm and 529nm, respectively. The emitted fluorescence is assumed to be proportional to the concentration of hydrogen peroxide in the cells . The results are expressed as a percentage of decrease in the H2O2 production by HFDPC in comparison with the untreated control cells.
The inter-group comparisons were performed by an Unpaired Student’s t-Test: *p<0.05, **p<0.01 and ***p<0.001.
Greyverse™ is able to decrease the internal H2O2 production in an HFDPC culture by 30%.
Greyverse™ decreases H2O2 accumulation thus decreasing oxidative stress involved in the greying hair process.
EX VIVO EFFECT OF GREYVERSE™ ON OXIDATIVE ENZYME EXPRESSION
Oxidative stress is one of the main causes of the greying process. The excess of free radicals degrades melanin and lowers the capacity of the melanocytes to synthetize melanin. Shi and al. have shown that a deficiency of catalase, the enzyme that allows the transformation of hydrogen peroxide into oxygen and water (2 H2O2 → 2 H2O + O2) in human hair follicles, largely contributes to the greying of hair . Moreover, TRP-2 expression was shown to be uncoupled to that of tyrosinase and TRP-1 in hair bulb melanocytes, whatever the hair colour and ethnic origin , suggesting a specific role of this enzyme apart from pigmentation through melanin synthesis. Michard et al. investigated the TRP-2 effects on oxidative stress-mediated toxicity . They demonstrated that TRP-2 over-expression reduces H2O2-induced DNA damage, with a significant improvement of respiration and survival rate without any impact on cell proliferation. Additionally, they demonstrated that TRP-2 silencing partially restores sensitivity to oxidative stress. The importance of TRP-2 as a protector for hair follicle and hair colour preservation is further confirmed by the fact that TRP-2 expression is preserved in eyelash follicle melanocytes : it would explain eyelash protection against greying. Altogether, we can seriously presume that catalase and TRP-2 contribute to protecting hair follicle melanocytes from oxidation, and that their specific lack leads to hair follicle susceptibility to oxidation  and largely contributes to the greying of hair.
The aim of this study was to determine ex vivo the effects of Greyverse™ on oxidative enzymes (catalase and TRP-2) implicated in the greying hair process.
Palmitoyl Tetrapeptide-20 (pure peptide contained in Greyverse™) was tested at concentrations of 10-9 M and 10-7M, equivalent to 0.005% and 0.5% Greyverse™, respectively.
On a scalp plasty coming from a 71-year-old Caucasian woman, grey hair follicles (from the infundibulum to the bulb) were isolated by microdissection on day 0. These hair follicles were placed separately in a 48-well plate and kept in survival for seven days in William’s medium (Sigma-Aldrich, W1878) supplemented with L-glutamine, insulin, hydrocortisone, serum and antibiotics, at 37°C in a 5% CO2 atmosphere. Eleven hair follicles were used per condition (untreated or treated). Palmitoyl Tetrapeptide-20 was diluted at 10-9 M and 10-7 M in the culture medium on day 0, day 1, day 4 and day 7 whereas the medium of the untreated hair follicles was renewed.
At the end of survival (day 7), hair follicles were fixed in a buffered formalin solution, dehydrated, and paraffin impregnated. 7-µm-thick paraffin sections were mounted on glass slides for immunostainings and stainings.
- For fluorescent immunostainings, the primary antibody used was i-PARD3/ASIP (Abcam, ref. ab64646). The sections were then incubated for 30 minutes at room temperature with the Alexa Fluor 488-labeled antibody (Lifetechnologies, ref. A11078). The nuclei were counter-stained using propidium iodide at 0.2µg/mL. The slides were finally mounted using Vectashield® mounting medium (Vector, ref. H-1400).
- For Immunohistochemistry, the hair sections were pre-incubated with hydrogen peroxide (VWR, ref. 23619.264) to inactivate endogenous peroxidase activity. The primary antibodies used were anti-TRP1 (Eurogentec, ref. SIG-38150-1000) and anti-Melan-A (Santa Cruz biotechnologies, ref. sc-20032). Then, the sections were pre-incubated with a biotinylated secondary antibody and incubated with a streptavidin-labeled peroxidase (Vector, Vectastain® Universal ABC kit, ref. PK7200). The staining was revealed by a substrate of peroxidase, VIP (Vector, ref. SK-4600). The nuclei were counter-stained using Mayer’s hemalum (RAL diagnostics, ref. 320550). The slides were finally mounted using Eukitt mounting medium (VWR, ref. KIND01250).
The microscopic observations were performed using a Leica DMLB or Olympus BX43 microscope. Pictures were digitized with a numeric DP72 Olympus camera with CellD storing software. Different hair parts were analyzed: infundibulum, upper shaft, bulge, lower shaft and bulb.
After 7 days of treatments with 10-9 M and 10-7 M Palmitoyl Tetrapeptide-20, an antioxidant activity was observed by immunostainings on micro-dissected human hair follicles.
The tyrosinase-related proteins TRP-2 was induced in the upper root sheaths.
The antioxidant enzyme catalase, known to block the deleterious whitening effect of hydrogen peroxide in hair, was increased in the lower root sheaths.
Greyverse™ decreases the enzymes involved in oxidative stress thus reducing the greying hair process.
Beauty Blogger Kerry Smith evaluates RevivHair REV:
This is my latest find in Self improvement Beauty products.
It is a serum used directly on the scalp with wet or dry hair. It is meant to be used 3 times day or so. I have been using it for about 6 weeks. I have been doing it three times pr day pretty faithfully but I will admit there were definitely a few sessions that I skipped. I always used it after the shower and right before bed, before putting on my silk sleeping hat. I tried most days to use some shortly after lunch, but it was occasionally right before dinner. i really just tried to make sure I was getting in three times for more effectiveness.
The serum itself has no aroma,.. it is pretty much odorless. It is a clearish like oil type serum substance, but it does not lave my hair greasy or weighed down. I actually think the main ingredient may be water since it is listed first. Which is probably why it is still light on my hair.
So I do not wear hair ties often because they tend to rip out a bunch of my hair. I did a tie test, and it was about two weeks of use from the first before test picture, to the second after test picture. You can see there was a lot more fallout breakage before I started using the RevivHair REV Serum.
SO here are some pics of my hairline before one wet one dry. You can see here there is no new growth, only sparce and thinning hair. So Sad!
So I do not wear hair ties often because they tend to rip out a bunch of my hair. I did a tie test, and it was about two weeks of use from the first before test picture, to the second after test picture. You can see there was a lot more fallout breakage before I started using theRevivHair REV Serum.
SO after testing this out for a month and a half or so, I am pretty happy with the results. My hairline and scalp are happy too! I did not experience any discomfort or itching at all while I was using this. If you re struggling with hair strength, breakage, loss or lack of luster, you should try this for yourself! Oh and as a bonus, it also helps to reverse grey hair! How is that for a nice bonus.
SO after testing this out for a month and a half or so, I am pretty happy with the results. My hairline and scalp are happy too! I did not experience any discomfort or itching at all while I was using this. If you re struggling with hair strength, breakage, loss or lack of luster, you should try this for yourself! Oh and as a bonus, it also helps to reverse grey hair! How is that for a nice bonus. I know platinum hair is the rage right now, but I will take my natural dark brown over salt and pepper hair every single day of the week!!
You can get some for yourself here:
#RevivHairREV #RevivSerums #greyhairreverse, #Greyverse, #Darkenyl, #thickerhair #RevivHair
Check out my You Tube Video showing the New Hair growth too!
Full review here:
Canities is the fancy word for premature greying of the hair, and most people have some amount of greying, from very sparse, to fairly widespread.
The color, density, and styling of hair have a colossal bearing on one’s self-esteem, especially in today’s times where a person’s first impression may turn out to his or her last impression. However, increased longevity of human life means that we spend an increasing proportion of our lives sporting signs of aging on our scalp. The most dramatic age-related change in hair is the onset of hair graying or canities, which is the gradual age-dependent dilution of hair color to gray or white, also known assenile canities (canities (L.), canus, hoary, gray). The graying of hair occurs due to an admixture of normally pigmented, hypomelanotic, and amelanotic melanosomes. White hair is the endpoint of graying. The age of onset of senile canities appears to be genetically controlled and inheritable. The average age for Caucasians is mid-30s; for Asians, late-30s; and for Africans, mid-40s. A good rule of thumb is that by 50 years of age, 50% of people have 50% gray hair. 
The darker the hair color, the more noticeable early graying will be. Particular hair colors are associated with some ethnic groups. The Fischer–Saller scale, named after Eugen Fischer and Karl Saller, is used to determine the shades of hair color [Table 2].  Majority of the human population (80–90%) fall into the U to Y category (dark brown/black hair) of this scale.
WHAT HAPPENS DURING PHYSIOLOGICAL AGING (CANITIES)?
The type of hair fiber keeps on changing with age. Neonates... have unpigmented lanugo hair while adults have short (mostly pigmented) vellus hair or fine pigmented intermediate hair and long terminal hair shafts. Similarly, surface morphology also shows variation with age, particularly with the reduction in the cuticular scale size. The synthetic capacity of hair bulb melanocytes is maximum during youth. An average scalp hair follicle usually receives 7 ± 15 melanocyte replacements from an outer root sheath reservoir to the hair bulb, which occurs in the first 45 years preceding the onset of gray hair. Different theories have been suggested for the age-related gradual loss of pigmentation. This includes exhaustion of enzymes involved in melanogenesis, impaired deoxyribonucleic acid (DNA) synthesis, loss of telomerase, loss of antioxidant mechanisms, and anti-apoptotic signals. Table 3 shows various changes that take place in a white hair bulb during canities. The net result is that fewer melanosomes are incorporated into cortical keratinocytes of the hair shaft. Cessation of pigment production by melanocytes in the hair matrix area surrounding the dermal papilla is a slow process resulting in slow outgrowth of graying hair at the pace of normal hair growth. All hair bulbs do not decrease pigment incorporation in the growing hair at the same time giving “salt and pepper pattern”to the scalp hair.
It has been observed that hair graying pattern depends on gender, age of onset, and smoking habits, with smokers having higher chances of having canities. Temporal area is involved in males first while in females, it is the frontal area. Age of onset also affects the area of involvement; parietal and occipital areas are involved in patients of young age while frontal area is involved in late onset group.
WHY DOES PREMATURE CANITIES OCCUR?
Premature canities is a common cause of referral to dermatologists. It occurs most commonly without any underlying pathology, but is said to be inherited in an autosomal dominant manner. It is different from poliosis which is circumscribed hypomelanosis of hair. The diseases associated with poliosis are given in Table 4. The pathogenesis of premature canities has not yet been clearly elucidated. A hypothesis that pH and cysteine level of melanosomes play critical roles in determining the course of mixed melanosomes leading to dark, light, or red hair phenotype has been proposed because of the diversity of human hair pigmentation. The role of pH in controlling mixed melanogenesis has attracted much attention as it is seen that tyrosinase activity is progressively suspended by lowering the pH, with a shift to more pheomelanin phenotype.[8-11] Concentration of cysteine in melanosomesis another control point in mixed melanogenesis. Chemical hair straightening is done by alkaline disruption of the disulphide bonds in the cortex of the hair shaft. It causes considerable damage to the hair because of the pH (9–12) of the chemicals leaving the hair dry and fragile. In a questionnaire-based study, Shetty et al. reported that 22% of the cases experienced graying of hair also.[8,12] There is definitely a role of trace metal ions in hair pigmentation. Copper ions are required by tyrosinase at its active center; thus, it is likely that copper ions in melanocytes are necessary to maintain normal color. Fatemi Naieni et al. compared the mean copper concentration in patients with PHG and controls and found lower mean serum copper concentration in the cases.
Data suggest that oxidative stress can also play a major role in the premature aging of skin and hair. This theory has been widely accepted these days. Reactive oxygen species (ROS) or free radicals, generated by a variety of internal and environmental factors may result in direct damage to various cellular structural membranes, lipids, proteins, and DNA. To combat these free radicals, our body has endogenous defense mechanisms such as antioxidative enzymes which include superoxide dismutase, catalase, glutathione peroxidase as well as non-enzymatic antioxidative molecules like vitamin E, vitamin C, glutathione, and ubiquinone. The production of these endogenous defense mechanisms decreases while that of free radical increases, resulting in aging.
APPROACH TO MANAGEMENT OF PREMATURE CANITIES
...Recent experimental work indicates that cinnamidopropyltrimonium chloride, a quaternized UV absorber, delivered from a shampoo system, is suitable for photo protection of hair, while simultaneously providing an additional conditional benefit on hair, Solid lipid nanoparticles have been developed as novel carriers of UV blockers for use on skin and hair, offering photoprotection on their own too by reacting and scattering ultraviolet radiation (UVR).[ 24]
Recent advances in the management of aging hair and scalp are anti-aging compounds. Shampoos are largely ineffective as anti-aging agents due to water dilution and short contact time, and antioxidants such as vitamin C and E in these preparations protect fatty substances in the shampoo from oxidation, and not the hair.
— Portions excerpted from Sehrawat M, Sinha S, Meena N, Sharma PK. Biology of hair pigmentation and its role in premature canities. Pigment Int 2017;4:7-12.
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Addressing greying hair isn't just a vanity issue; it's a scalp and skin health issue too.
Premature greying of the hair is a condition known as canities; the diminishing of pigment in hair producing a range of colors from normal to white that is perceived as gray.
It is a complex multi-factorial process mainly considered to be an interplay of nutritional, genetic and environmental factors. Nutritional deficiencies like vitamin B12 deficiency, severe iron deficiency, chronic protein loss, copper deficiency are often found associated with premature greying of hairs. Other factors that have been incriminated are low serum ferritin, and low serum calcium and vitamin D3 levels.
Smoking is another factor that is considered to be related to premature greying of hair. Smoking results in generation of huge amount of reactive oxygen species leading to increased oxidative stress culminating into damage to melanin producing cells, melanocytes. Prolonged exposure to ultraviolet rays is considered to initiate similar processes in hair follicles resulting in premature greying of hair.
It turns out that a key factor in hair color loss happens to be the buildup of hydrogen peroxide in the scalp and hair follicles. As we age, our bodies become less able to neutralize that hydrogen peroxide, which interferes with an enzyme that is responsible for producing the pigment in hair. The graying begins when the synthesis of melanin (the natural pigment that gives hair its color) is disrupted.
Another recent study in Nature Medicine suggests that sun damage may very well speed up the graying of hair. The study found that when UV exposure damaged skin, melanin-producing stem cells migrated upward to the skin to produce protective pigment (a tan) but abandoned their position in the hair follicle.
While there are many other factors that can contribute to graying hair (genetics, ethnicity, stress etc.), these studies suggest there are steps you can take to slow down or minimize graying hair:
The revolutionary ingredients, like Greyverse and Darkenyl, found in our RevivHair REV Stimulating Serum may help prevent hydrogen peroxide buildup and target tyrosinase to help prevent the loss of hair color and the appearance of darker hair, naturally without dyes or pigments. Another included ingredients (also mentioned in the study) may help: Methionine Sulfoxide Reductase.
Additionally, wearing a hat or applying a UV protection product for the hair (more specifically, the scalp) whenever you're outside, may help as well. Wearing a hat to shield UV damage is something we should be doing anyway!