Journal September 27, 2026 5 min read

Which peptides are studied in relation to transepidermal water loss?

A research-supply overview of peptide and peptide-containing formulations investigated for effects on transepidermal water loss (TEWL), including collagen tripeptide, sh-oligopeptide-1, and other actives studied in barri

peptides-pro Editorial

Transepidermal water loss (TEWL) is the passive diffusion of water through the stratum corneum, and it is widely used as a surrogate marker of skin-barrier integrity in dermatological research. Peptides studied in relation to TEWL include collagen tripeptide (CTP), sh-oligopeptide-1 (a synthetic epidermal growth factor), and larger collagen-peptide supplements, as well as peptide-adjacent actives such as panthenol, niacinamide, and Pro-Xylane that are frequently co-formulated with peptides in barrier-repair research. The work centres on epidermal barrier function and the Th2-mediated inflammatory pathways that disrupt it in atopic dermatitis (AD) and xerosis models.

Identifiers vary by compound: CTP is an amino-acid-rich collagen tripeptide with low antigenicity; sh-oligopeptide-1 is a synthetic EGF-like oligopeptide; AP collagen peptide (APCP) is a CTP-containing preparation. Where the evidence gives sequence, formula, or molecular weight, those values are reported in the sections below. The table summarises the models and measured outcomes.

Research Studies

AP collagen peptide and TEWL in an oxazolone-induced mouse model of atopic dermatitis

In hairless mice with oxazolone (OXZ)-induced AD-like skin, APCP (a CTP-containing preparation) was evaluated for effects on skin hydration and inflammatory responses. Skin hydration and transepidermal water loss were among the measured parameters. This is an animal model; findings are not established in humans [2].

Collagen tripeptide and barrier function in barrier-dysfunction models

CTP has been reported to improve skin hydration and barrier function, but its therapeutic effects in AD, particularly under conditions of barrier dysfunction, had not been fully established prior to the APCP study. The evidence for CTP in this context is therefore preliminary and largely model-based [2].

sh-oligopeptide-1 emulgel and TEWL in paediatric atopic dermatitis

A randomised, self-controlled trial in 57 children (aged 2–14) applied an emulgel containing hyaluronic acid, glycerol, grape seed oil, Calendula officinalis, aloe vera, and sh-oligopeptide-1 (a synthetic epidermal growth factor) twice daily for 10 days to one forearm, with the other forearm as control. TEWL, stratum corneum hydration (SCH), erythema, and pH were measured. This is a clinical study in a paediatric AD population [5].

Oral bioactive collagen peptides and skin properties

A randomised, controlled trial evaluated daily oral intake of a collagen peptides supplement in 68 healthy women aged 35–65 with visible facial wrinkles. Participants were allocated 1:1 to active control (n = 34) or avvera™ (n = 34); one participant in the active control group withdrew, leaving 67 in the final analysis. Skin properties and aging hallmarks were assessed. TEWL was not the primary reported outcome in the available summary [6].

Vitamin K2 (MK-7) cream and TEWL in a split-face/neck trial

A clinical trial in 36 women aged 35–60 with facial dryness, dullness, laxity, and neck lines evaluated a facial and neck cream containing vitamin K2 (MK-7). The stated aims included whether the test cream improves skin hydration (Corneometer), reduces TEWL (Vapometer), and enhances elasticity and firmness (Cutometer) versus a control cream, and whether it reduces wrinkle severity (Rz and Ra via AEVA-HE imaging). This is a clinical trial protocol; results were not available in the evidence provided [7].

Topical panthenol, niacinamide, and dipotassium glycyrrhizate in xerosis

A 28-day randomised, split-leg, untreated-controlled trial in subjects with xerosis cutis applied a topical formulation containing panthenol, niacinamide, and dipotassium glycyrrhizate twice daily to one pretibial area, with the contralateral leg untreated. TEWL and hydration were assessed. This is a clinical study in a xerosis population [3].

NPQ Plus supplementation and skin health

A single-arm, open-label study in 55 healthy adults with skin concerns evaluated NPQ Plus, a multi-component nutraceutical containing polyphenols (Oligonol®), nicotinamide mononucleotide (NMN; RevAge®), pyrroloquinoline quinone (PQQ; PureQQ®), coenzyme Q10, and a trace mineral complex (Ioniplex). Participants consumed one sachet daily for 12 weeks, with assessments at baseline and Weeks 4 and beyond. TEWL was not specified as a primary outcome in the available summary [4].

Vernix caseosa retention and atopic dermatitis prevention

Vernix caseosa is a naturally occurring, white, creamy substance covering newborn skin at birth, formed during the last trimester. A clinical trial is evaluating retention of vernix caseosa in newborns for primary prevention of atopic dermatitis. AD affects up to one in five children worldwide and involves skin-barrier integrity and the skin microbiome in early life. This is a prevention study, not a peptide study, and is included for context on barrier-focused research [1].

Mushroom extract formulation during breast radiotherapy

A study evaluated a mushroom extract-containing topical cosmetic formulation for skin care in women receiving radiotherapy to the breast after breast-conserving surgery. Participants were randomised to the investigational formulation or usual moisturising care, applied twice daily from approximately 15 days before radiotherapy through the ~3-week radiotherapy period and 1 month after. Skin condition was assessed. TEWL was not specified as an outcome in the available summary [8].

Compound or formulation	Model or population	TEWL reported?
APCP (CTP-containing)	Oxazolone-induced AD-like hairless mice	Yes (measured)
sh-oligopeptide-1 emulgel	Children aged 2–14 with AD	Yes (measured)
Panthenol, niacinamide, dipotassium glycyrrhizate	Adults with xerosis cutis	Yes (measured)
Vitamin K2 (MK-7) cream	Women aged 35–60	Yes (stated aim)
Oral bioactive collagen peptides	Women aged 35–65	Not specified
NPQ Plus	Healthy adults with skin concerns	Not specified

If you are reading this for personal health reasons

The materials described here are sold for laboratory research only. We do not provide dosing, medical guidance, or recommendations for personal use. Anyone considering a compound for themselves should speak to a licensed clinician.