Facial application of high-concentration carbon dioxide prevents epidermal impairment associated with environmental changes

Figures & data

Figure 1 Changes in epidermal function with CO₂ application.

Notes: Each parameter is shown as the amount of change (Δ) from 0 week to 4 or 8 weeks for TEWL (A) and conductance (B). Values are mean±SE (n=19). ^#P<0.05, ##P<0.01 vs 0 week by Dunnett’s test. *P<0.05 vs control at 8 weeks via paired t-test. Difference in ΔConductance between the two conditions was statistically significant via two-way repeated measures ANOVA.
Abbreviation: TEWL, transepidermal water loss.

Table 1 Parameters of epidermal function at each time point

		0 week	4 weeks	8 weeks
TEWL (μg/m^2/h)	Control	27.6±1.0	35.1±1.6	34.4±1.4
	CO2	30.6±1.4	34.8±1.6	35.6±1.6
Conductance (μS)	Control	89.6±8.7	58.9±7.7	59.6±6.2
	CO2	83.4±9.8	67.0±8.8	72.1±7.4*

Notes: Values are mean±SE (n=19).

* P<0.05 vs control at 8 weeks via paired t-test. Conductance, water content in the stratum corneum.

Abbreviation: TEWL, transepidermal water loss.

Figure 2 Changes in skin surface profile with CO₂ application.

Notes: Each parameter is shown as the amount of change (Δ) from 0 week to 4 or 8 weeks for SESC. Values are mean±SE (n=19). ^#P<0.05, ^##P<0.01 vs 0 week by Dunnett’s test. *P<0.05 vs control at 8 weeks via paired t-test. Difference in ΔSESC between two conditions was statistically significant via two-way repeated measures ANOVA.
Abbreviation: SESC, skin scaliness.

Table 2 Parameters of the skin surface profile and property at each time point

		0 week	4 weeks	8 weeks
SESM	Control	114.5±5.8	121.1±7.7	120.4±6.2
	CO2	114.2±7.8	118.2±8.8	110.6±7.4*
SER	Control	2.9±0.2	3.3±1.6	3.3±1.4
	CO2	3.0±0.2	3.2±1.6	2.9±1.6
SESC	Control	0.5±0.0	0.9±1.7	0.8±1.7
	CO2	0.6±0.1	0.8±2.2	0.6±2.2*
SEW	Control	95.6±5.2	99.5±7.7	104.5±6.2
	CO2	102.9±6.5	97.1±8.8	94.3±7.4*
pH	Control	5.9±0.1	5.8±0.1	6.0±0.1
	CO2	5.8±0.1	5.8±2.2	6.0±0.1
L*	Control	62.3±5.8	62.2±0.5	62.3±0.6
	CO2	62.4±7.8	62.3±0.4	62.5±0.6
a*	Control	13.2±5.2	13.7±0.3	13.5±0.3
	CO2	13.1±6.5	13.9±0.3	13.7±0.3
b*	Control	17.8±0.0	17.3±0.4	17.0±0.4
	CO2	18.0±0.1	17.1±0.4	17.0±0.4

Notes: Values are mean±SE (n=19).

* P<0.05 vs control at 8 weeks via paired t-test. L^*, color property related to brightness; a^*, color property related to redness; b^*, color property related to yellowness; pH, skin surface pH.

Abbreviations: SER, roughness; SESC, scaliness; SESM, skin smoothness; SEW, wrinkles.

Figure 3 Changes in skin surface appearance.

Notes: Microscopic skin surface images from 0, 4, and 8 weeks obtained with the dry skin microscope are shown. The magnification rate was 30 times. The length of the long side was 6 mm.