The DOI matches its Crossref record; 46 of the 46 references it cites were found in a registry or an index; 1 of the 20 sources its claims cite were checked for support.
Ferulic Acid Stabilizes a Solution of Vitamins C and E and Doubles its Photoprotection of Skin
Open accessAbstract
Ferulic acid is a potent ubiquitous plant antioxidant. Its incorporation into a topical solution of 15%l-ascorbic acid and 1%alpha-tocopherol improved chemical stability of the vitamins (C+E) and doubled photoprotection to solar-simulated irradiation of skin from 4-fold to approximately 8-fold as measured by both erythema and sunburn cell formation. Inhibition of apoptosis was associated with reduced induction of caspase-3 and caspase-7. This antioxidant formulation efficiently reduced thymine dimer formation. This combination of pure natural low molecular weight antioxidants provides meaningful synergistic protection against oxidative stress in skin and should be useful for protection against photoaging and skin cancer.
Overview
AI snapshot
Written from the paper’s full text.
TL;DR
Adding ferulic acid to a topical solution of vitamins C and E improved the vitamins’ chemical stability and raised photoprotection against simulated sunlight in pig skin from roughly fourfold to about eightfold. The authors propose that this triple antioxidant combination may help prevent photoaging and skin cancer.
Key findings
- A formulation containing 0.5% ferulic acid, 15% L-ascorbic acid, and 1% α-tocopherol provided approximately 8-fold photoprotection, compared with about 4-fold for ferulic acid alone or vitamins C + E alone, as measured by erythema and sunburn cell counts.
- After 1 month at 45°C, ferulic acid preserved more than 90% of L-ascorbic acid and 100% of α-tocopherol.
- The triple combination reduced activation of caspase-3 and caspase-7 after 4× and 8× minimal erythema dose (MED) of solar-simulated radiation; at 8× MED, protection was nearly complete.
- Thymine dimer formation after 8× MED was about one-third positive with ferulic acid alone, about 15% positive with vitamins C + E, and completely negative with the triple combination.
Methods
- Weanling white Yorkshire pigs were pretreated topically for 4 consecutive days with vehicle, 0.5% ferulic acid, 15% L-ascorbic acid + 1% α-tocopherol, or the triple combination, then exposed to solar-simulated radiation from 2× to 10× MED at 2× MED intervals, with evaluation 24 hours later.
- Outcomes included antioxidant protection factor, colorimetric erythema, sunburn cell counts, western blotting for caspase-3 and caspase-7, and immunohistochemistry for thymine dimers.
- Results are reported as mean ± SD, with p-values from two-tailed Student’s t-tests; photoprotection experiments used n = 6, and caspase experiments used n = 3.
Limitations
- The paper states that the mechanism by which ferulic acid stabilizes vitamins C and E is unknown, that no dose-response effect supported a sunscreen mechanism, and that the authors could not yet measure effects on UV-induced 8-oxo guanine formation.
- Evident from the text: the main photoprotection experiments were performed in pig skin rather than human skin, and sample sizes were small (n = 6 or n = 3 depending on assay). The paper does not include a dedicated limitations section.
Model-written summary. Check it against the paper before relying on it.
Integrity signals
Registry
Cites
Statistics
Verification
Claims the paper makes
18 Own result · 15 No full text of the sources · 7 Own interpretation · 1 Supported · 1 Sources not found · 1 Own method · 1 No basis given
Every source the paper cites for this claim was checked and supports it.
In the paper
“Indeed a recent study of three high SPF broad-screen sunscreens revealed that at 2 mg per cm 2 application, UVAinduced free radical formation was reduced only 55% with even worse protection when application levels were decreased (Haywood et al, 2003).”
§ Ferulic Acid Stabilizes a Solution of Vitamins C and E and Doubles its Photoprotection of Skin > Discussion
What the sources say
- Supportedcites Haywood et al, 2003 source
The paper describes testing three SPF 20+ sunscreens claiming UVA protection. Its Discussion reports about a 55% reduction in UVA-induced free-radical production at the recommended 2 mg/cm² application and about a 45% reduction at the lower application level tested (0.5–1.5 mg/cm²). (LLM, conf=0.95)
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
- Supported
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Figure 2a reveals protection by antioxidant solutions of activation of caspase-3 by 4 Â and 8 Â MED of solar-simulated radiation.”
§ Ferulic Acid Stabilizes a Solution of Vitamins C and E and Doubles its Photoprotection of Skin > Results
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
- Rests on an assumption: The porcine skin model used in the experiments is predictive of human skin photoprotection.
- Rests on an assumption: Activation of caspase-3 and caspase-7 is a valid marker of apoptosis in this model.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Its incorporation into a topical solution of 15% L-ascorbic acid and 1% a-tocopherol improved chemical stability of the vitamins (C þ E) and doubled photoprotection to solarsimulated irradiation of skin from 4-fold to approximately 8-fold as measured by both erythema and sunburn cell formation.”
- Also stated in: § Abstract · plain
“We were surprised to find that in addition to improving stability, adding 0.5% ferulic acid to the solution of 15% L- ascorbic acid and 1% a-tocopherol doubled photoprotection when applied topically to skin from 4-to 8-fold.”
§ Ferulic Acid Stabilizes a Solution of Vitamins C and E and Doubles its Photoprotection of Skin > Abstract
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
- Rests on an assumption: The porcine skin model used in the experiments is predictive of human skin photoprotection.
- Also stated in: § Abstract · plain
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Our studies revealed no evidence of a dose-response effect to support a sunscreen mechanism (Fig 5).”
§ Ferulic Acid Stabilizes a Solution of Vitamins C and E and Doubles its Photoprotection of Skin > Discussion
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Figure 2d shows relative antioxidant protection, which is virtually complete by vitamins C, E and ferulic acid.”
§ Ferulic Acid Stabilizes a Solution of Vitamins C and E and Doubles its Photoprotection of Skin > Results
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
- Rests on an assumption: The porcine skin model used in the experiments is predictive of human skin photoprotection.
- Rests on an assumption: Activation of caspase-3 and caspase-7 is a valid marker of apoptosis in this model.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Inhibition of apoptosis was associated with reduced induction of caspase-3 and caspase-7.”
§ Ferulic Acid Stabilizes a Solution of Vitamins C and E and Doubles its Photoprotection of Skin > Abstract
plaincorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
- Rests on an assumption: Activation of caspase-3 and caspase-7 is a valid marker of apoptosis in this model.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“After 4 Â MED, ferulic acid-treated skin was still positive in approximately 25% of both epidermis and dermis (data not shown).”
§ Ferulic Acid Stabilizes a Solution of Vitamins C and E and Doubles its Photoprotection of Skin > Results
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
- Rests on an assumption: The porcine skin model used in the experiments is predictive of human skin photoprotection.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Skin treated with vitamins C, E, and ferulic acid was completely negative (Fig 4d).”
§ Ferulic Acid Stabilizes a Solution of Vitamins C and E and Doubles its Photoprotection of Skin > Results
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
- Rests on an assumption: The porcine skin model used in the experiments is predictive of human skin photoprotection.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“With 4 Â MED of solar-simulated irradiation, both control and vehicle-treated skin showed virtually uniform nuclear fluorescence in both epidermis and papillary dermis (Fig 4a).”
§ Ferulic Acid Stabilizes a Solution of Vitamins C and E and Doubles its Photoprotection of Skin > Results
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
- Rests on an assumption: The porcine skin model used in the experiments is predictive of human skin photoprotection.
- Rests on an assumption: The vehicle used does not itself affect the measured photoprotection outcomes.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“These studies support the hypotheses that UV radiation produces apoptosis by triggering the caspase cascade in both epidermis and dermis, and topical vitamins C, E, and ferulic acid can protect against caspase activation.”
§ Ferulic Acid Stabilizes a Solution of Vitamins C and E and Doubles its Photoprotection of Skin > Discussion
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
- Rests on an assumption: Activation of caspase-3 and caspase-7 is a valid marker of apoptosis in this model.
In the paper
“Vitamin E is delivered to the surface of skin through sebum to protect the stratum corneum from this oxidative insult (Thiele, 2001).”
§ Ferulic Acid Stabilizes a Solution of Vitamins C and E and Doubles its Photoprotection of Skin > Discussion
What the sources say
- Not checked — no full text of the sourcecites Thiele, 2001 source
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“The demonstrated protection of topical application of vitamins C, E, and ferulic acid against UV-induced thymine dimer formation supports its use for the prevention of skin cancer.”
§ Ferulic Acid Stabilizes a Solution of Vitamins C and E and Doubles its Photoprotection of Skin > Discussion
boosteddirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
- Rests on an assumption: The porcine skin model used in the experiments is predictive of human skin photoprotection.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“This antioxidant formulation efficiently reduced thymine dimer formation.”
- Also stated in: § Discussion · plain
“Moreover it provides additional protection against thymine dimer formation that should prove useful for prevention of skin cancer.”
§ Ferulic Acid Stabilizes a Solution of Vitamins C and E and Doubles its Photoprotection of Skin > Abstract
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
- Rests on an assumption: The porcine skin model used in the experiments is predictive of human skin photoprotection.
- Also stated in: § Discussion · plain
In the paper
“We have previously demonstrated that topical vitamins C þ E could prevent UV-induced thymine dimer formation (Lin et al, 2003).”
§ Ferulic Acid Stabilizes a Solution of Vitamins C and E and Doubles its Photoprotection of Skin > Results
What the sources say
- Not checked — no full text of the sourcecites Lin et al, 2003 source
hedgedconditional- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“These studies support the hypotheses that UV radiation produces apoptosis by triggering the caspase cascade in both epidermis and dermis, and topical vitamins C, E, and ferulic acid can protect against caspase activation.”
§ Ferulic Acid Stabilizes a Solution of Vitamins C and E and Doubles its Photoprotection of Skin > Discussion
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
- Rests on an assumption: Activation of caspase-3 and caspase-7 is a valid marker of apoptosis in this model.
In the paper
“Ferulic acid augments the protection of vitamins C þ E previously demonstrated to prevent UV-induced thymine dimer formation when applied topically to skin (Lin et al, 2003).”
§ Ferulic Acid Stabilizes a Solution of Vitamins C and E and Doubles its Photoprotection of Skin > Discussion
What the sources say
- Not checked — no full text of the sourcecites Lin et al, 2003 source
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
- Rests on an assumption: The porcine skin model used in the experiments is predictive of human skin photoprotection.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“This combination of pure natural low molecular weight antioxidants provides meaningful synergistic protection against oxidative stress in skin and should be useful for protection against photoaging and skin cancer.”
§ Ferulic Acid Stabilizes a Solution of Vitamins C and E and Doubles its Photoprotection of Skin > Abstract
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
- Rests on an assumption: The porcine skin model used in the experiments is predictive of human skin photoprotection.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Since SPF is an exponential measurement, at reduced levels, relative photoprotection of any sunscreen is no more than 3-4-fold.”
§ Ferulic Acid Stabilizes a Solution of Vitamins C and E and Doubles its Photoprotection of Skin > Discussion
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
In the paper
“The solution must be formulated at a pH of 3.5 or lower for the vitamin C to be absorbed into skin: at this pH the vitamin C is protonated and the molecule is uncharged (Pinnell et al, 2001).”
§ Ferulic Acid Stabilizes a Solution of Vitamins C and E and Doubles its Photoprotection of Skin > Abstract
What the sources say
- Not checked — no full text of the sourcecites Pinnell et al, 2001 source
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
In the paper
“We have previously reported that a stable aqueous solution of 15% vitamin C (L-ascorbic acid) and 1% vitamin E (a-tocopherol) when applied topically to skin can provide 4-fold photoprotection for skin (Lin et al, 2003).”
§ Ferulic Acid Stabilizes a Solution of Vitamins C and E and Doubles its Photoprotection of Skin > Abstract
What the sources say
- Not checked — no full text of the sourcecites Lin et al, 2003 source
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
In the paper
“Topical application of ferulic acid inhibited UVB-induced erythema (Saija et al, 2000).”
§ Ferulic Acid Stabilizes a Solution of Vitamins C and E and Doubles its Photoprotection of Skin > Discussion
What the sources say
- Not checked — no full text of the sourcecites Saija et al, 2000 source
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
In the paper
“It would not be expected to directly protect these vitamins since its redox potential (0.595) is appreciably higher than vitamin C (0.282) or vitamin E (0.48) (Lu and Liu, 2002).”
§ Ferulic Acid Stabilizes a Solution of Vitamins C and E and Doubles its Photoprotection of Skin > Discussion
What the sources say
- Not checked — no full text of the sourcecites Lu and Liu, 2002 source
hedged- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Ferulic acid's effect on photoprotection is most likely related to its antioxidant activity.”
§ Ferulic Acid Stabilizes a Solution of Vitamins C and E and Doubles its Photoprotection of Skin > Discussion
hedgedconditional- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
- It may state two separate claims as one. 16
- The quote only partly states this claim. 2
- Probably not a substantial claim. 5
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“After 8 Â MED, ferulic acidtreated skin was about one third positive (Fig 4b) and vitamin C þ E-treated skin was about 15% positive and fluorescence was less intense (Fig 4c).”
§ Ferulic Acid Stabilizes a Solution of Vitamins C and E and Doubles its Photoprotection of Skin > Results
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
- Rests on an assumption: The porcine skin model used in the experiments is predictive of human skin photoprotection.
In the paper
“Its incorporation into a topical solution of 15% L-ascorbic acid and 1% a-tocopherol improved chemical stability of the vitamins (C þ E)”
- Also stated in: § Abstract · plain
“We have learned that addition of ferulic acid, a ubiquitous plant antioxidant, provided stability of more than 90% for L-ascorbic acid and 100% for a-tocopherol (Zielinski and Pinnell, 2004).”
§ Ferulic Acid Stabilizes a Solution of Vitamins C and E and Doubles its Photoprotection of Skin > Abstract
What the sources say
- Not matchedcites Zielinski and Pinnell, 2004
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one. The quote only partly states this claim.
- Also stated in: § Abstract · plain
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Sunburn cell counts of combination of vitamins C, E, and ferulic acid were statistically different from control and vehicle at all MED tested and different from ferulic acid alone as well as from the combination of vitamins C þ E at 2 Â , 4 Â , 6 Â , and 8 Â MED.”
§ Ferulic Acid Stabilizes a Solution of Vitamins C and E and Doubles its Photoprotection of Skin > Results
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
- Rests on an assumption: The porcine skin model used in the experiments is predictive of human skin photoprotection.
- Rests on an assumption: The vehicle used does not itself affect the measured photoprotection outcomes.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Colorimetric measurements of combination of vitamins C, E, and ferulic acid were statistically different from control and vehicle at all minimal erythema dose (MED) tested; different from ferulic acid alone at 2 Â , 6 Â , and 8 Â MED; and different from combination vitamins C þ E at 4 Â and 6 Â MED.”
§ Ferulic Acid Stabilizes a Solution of Vitamins C and E and Doubles its Photoprotection of Skin > Results
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
- Rests on an assumption: The porcine skin model used in the experiments is predictive of human skin photoprotection.
- Rests on an assumption: The vehicle used does not itself affect the measured photoprotection outcomes.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Activation occurs in both epidermis and dermis (Fig 3a-c); in epidermis, activation is particularly strong in the basal layer.”
§ Ferulic Acid Stabilizes a Solution of Vitamins C and E and Doubles its Photoprotection of Skin > Results
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
- Rests on an assumption: The porcine skin model used in the experiments is predictive of human skin photoprotection.
- Rests on an assumption: Activation of caspase-3 and caspase-7 is a valid marker of apoptosis in this model.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“The combination of 15% L-ascorbic acid, 1% atocopherol, 0.5% ferulic acid provided approximately 8-fold protection and was statistically different than ferulic acid alone or the combination of vitamins C and E (Fig 1a, b).”
§ Ferulic Acid Stabilizes a Solution of Vitamins C and E and Doubles its Photoprotection of Skin > Results
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
- Rests on an assumption: The porcine skin model used in the experiments is predictive of human skin photoprotection.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Figure 2c shows activation of caspase-7 by 4 Â and 8 Â MED of solar-simulated radiation and protection by antioxidant solutions.”
§ Ferulic Acid Stabilizes a Solution of Vitamins C and E and Doubles its Photoprotection of Skin > Results
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
The quote only partly states this claim.
- Rests on an assumption: The porcine skin model used in the experiments is predictive of human skin photoprotection.
- Rests on an assumption: Activation of caspase-3 and caspase-7 is a valid marker of apoptosis in this model.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“With 8 Â MED of irradiation, protection of vitamin C, E, and ferulic acid is almost complete and is better than vitamin C and E or ferulic acid alone.”
§ Ferulic Acid Stabilizes a Solution of Vitamins C and E and Doubles its Photoprotection of Skin > Results
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
- Rests on an assumption: The porcine skin model used in the experiments is predictive of human skin photoprotection.
- Rests on an assumption: Activation of caspase-3 and caspase-7 is a valid marker of apoptosis in this model.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“It had no appreciable effect on ascorbic acid absorption (data not shown).”
§ Ferulic Acid Stabilizes a Solution of Vitamins C and E and Doubles its Photoprotection of Skin > Discussion
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Both 0.5% ferulic acid alone and 15% L-ascorbic acid þ 1% a-tocopherol together provided about 4-fold protection (Fig 1a, b).”
§ Ferulic Acid Stabilizes a Solution of Vitamins C and E and Doubles its Photoprotection of Skin > Results
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
- Rests on an assumption: The porcine skin model used in the experiments is predictive of human skin photoprotection.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Ferulic acid alone (3b) and vitamins C þ E (3c) provide partial protection but vitamins C, E, and ferulic acid (3d) provides virtually complete protection.”
§ Ferulic Acid Stabilizes a Solution of Vitamins C and E and Doubles its Photoprotection of Skin > Results
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
- Rests on an assumption: The porcine skin model used in the experiments is predictive of human skin photoprotection.
- Rests on an assumption: Activation of caspase-3 and caspase-7 is a valid marker of apoptosis in this model.
A claim is checked only against the cited paper’s full text, never its abstract, and none is available for its sources.
In the paper
“Sun protection factor is measured at 2 mg per cm 2 , yet in actual use, sunscreen application is only 0.4-0.5 mg per cm 2 (Wulf et al, 1997;Autier et al, 2001).”
§ Ferulic Acid Stabilizes a Solution of Vitamins C and E and Doubles its Photoprotection of Skin > Discussion
What the sources say
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
In the paper
“Approximately one third of UVA-induced oxidative stress in skin occurs at the surface of skin (Ou-Yang et al, 2004).”
§ Ferulic Acid Stabilizes a Solution of Vitamins C and E and Doubles its Photoprotection of Skin > Discussion
What the sources say
- Not checked — no full text of the sourcecites Ou-Yang et al, 2004 source
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it.
The paper states this without a source or data behind it here, so there is nothing to check it against. The quote shows it is in the paper.
In the paper
“In addition, SPF is a measurement of UVB only and reveals nothing about UVA photoprotection, protection necessary to protect against oxidative stress.”
§ Ferulic Acid Stabilizes a Solution of Vitamins C and E and Doubles its Photoprotection of Skin > Discussion
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
In the paper
“With daily oral supplements of 3 g vitamin C and 2 g vitamin E, protection against photodamage in skin is increased approximately 1.5 times; either vitamin alone is ineffective (Fuchs and Kern, 1998).”
§ Ferulic Acid Stabilizes a Solution of Vitamins C and E and Doubles its Photoprotection of Skin > Abstract
What the sources say
- Not checked — no full text of the sourcecites Fuchs and Kern, 1998 source
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
In the paper
“Ferulic acid is a potent antioxidant with synergistic interactions with ascorbic acid (Trombino et al, 2004).”
§ Ferulic Acid Stabilizes a Solution of Vitamins C and E and Doubles its Photoprotection of Skin > Discussion
What the sources say
- Not checked — no full text of the sourcecites Trombino et al, 2004 source
plaincorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
In the paper
“Ferulic acid absorbs UV radiation with an absorption maximum at 307 nm (log e ¼ 4.19) (Graf, 1992).”
§ Ferulic Acid Stabilizes a Solution of Vitamins C and E and Doubles its Photoprotection of Skin > Discussion
What the sources say
- Not checked — no full text of the sourcecites Graf, 1992 source
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it.
A claim is checked only against the cited paper’s full text, never its abstract, and none is available for its sources.
In the paper
“Ferulic acid is a potent phenolic antioxidant found ubiquitously and at high concentrations in plants (Graf, 1992;Rice-Evans et al, 1996;Ou and Kwok, 2004).”
§ Ferulic Acid Stabilizes a Solution of Vitamins C and E and Doubles its Photoprotection of Skin > Discussion
What the sources say
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it. It may state two separate claims as one.
What the paper did — it cites no source for this, so there is none to check. The quote shows it is in the paper.
In the paper
“Experiments were performed on weanling white Yorkshire pigs in accord with the guidelines prepared by the Committee on Care and Use of Laboratory Animals of the Institute of Laboratory Resources, National Research Council (National Institutes of Health, publication No. 86-23, revised 1996).”
§ Ferulic Acid Stabilizes a Solution of Vitamins C and E and Doubles its Photoprotection of Skin > Treatment and irradiation procedure
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it.
In the paper
“Fifteen percent L-ascorbic acid saturates skin in 3 d; its tissue half life is about 4 d (Pinnell et al, 2001).”
§ Ferulic Acid Stabilizes a Solution of Vitamins C and E and Doubles its Photoprotection of Skin > Abstract
What the sources say
- Not checked — no full text of the sourcecites Pinnell et al, 2001 source
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
In the paper
“Vitamins C and E interact synergistically to protect each other and increase overall effectiveness (Pinnell et al, 2001).”
§ Ferulic Acid Stabilizes a Solution of Vitamins C and E and Doubles its Photoprotection of Skin > Abstract
What the sources say
- Not checked — no full text of the sourcecites Pinnell et al, 2001 source
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
The paper relies on this without support.
The porcine skin model used in the experiments is predictive of human skin photoprotection.
“Experiments were performed on weanling white Yorkshire pigs in accord with the guidelines prepared by the Committee on Care and Use of Laboratory Animals of the Institute of Laboratory Resources, National Research Council (National Institutes of Health, publication No. 86-23, revised 1996).”
The paper relies on this without support.
Activation of caspase-3 and caspase-7 is a valid marker of apoptosis in this model.
“In an effort to explore the mechanism of apoptosis in these experiments, western blots were carried out to determine levels of caspase-3 and its downstream effector, caspase-7.”
The paper relies on this without support.
The vehicle used does not itself affect the measured photoprotection outcomes.
“Skin was pretreated with vehicle, 0.5% ferulic acid, 15% vitamin C and 1% vitamin E, 15% vitamin C and 1% vitamin E, and 0.5% ferulic acid and irradiated with solar-simulated radiation 2 Â to 10 Â minimal erythema dose (MED) at 2 Â MED intervals.”
The paper relies on this without support.
Chemical stability at 45°C for 1 month predicts stability under normal storage conditions.
“Chemical stability was determined after 1 mo at 451C.”
Claims other papers make about this one
Each is checked against this paper’s own text: does it say what the citing paper says it does?
The cited source says what the claim attributes to it.
In the citing paper
“This suggests a role for topical CEFer in protecting against photoaging and skin cancers [64, 65].”
From Sunscreens and Photoaging: A Review of Current Literature (2021) · cites this paper as [64]
The cited source says what the claim attributes to it.
In the citing paper
“It is not synthesized by the human body and must be replenished via oral intake [64].”
From Sunscreens and Photoaging: A Review of Current Literature (2021) · cites this paper as [64]
The cited source says what the claim attributes to it.
In the citing paper
“a stable formulation can be made by compounding it with other antioxidants: vitamin E (alpha-tocopherol) and ferulic acid [61, 64].”
From Sunscreens and Photoaging: A Review of Current Literature (2021) · cites this paper as [64]
Citations
Cites
Structure-antioxidant activity relationships of flavonoids and phenolic acids
Rice-Evans, C. A., Miller, N. J., & Paganga, G. (1996) · Free Radical Biology and Medicine · doi:10.1016/0891-5849(95)02227-9 · Cited by 9,085
Vitamin C as an Antioxidant: Evaluation of Its Role in Disease Prevention
Padayatty, S. J., Katz, A., Wang, Y., Eck, P., Kwon, O., Lee, J.-H., Chen, S., Corpe, C., Dutta, A., Dutta, S. K., et al. (2003) · Journal of the American College of Nutrition · doi:10.1080/07315724.2003.10719272 · Cited by 1,949
Antioxidant potential of ferulic acid
Graf, E. (1992) · Free Radical Biology and Medicine · doi:10.1016/0891-5849(92)90184-i · Cited by 1,115
Antioxidant Properties of Ferulic Acid and Its Related Compounds
Kikuzaki, H., Hisamoto, M., Hirose, K., Akiyama, K., & Taniguchi, H. (2002) · Journal of Agricultural and Food Chemistry · doi:10.1021/jf011348w · Cited by 1,016
Ferulic acid: pharmaceutical functions, preparation and applications in foods
Ou, S., & Kwok, K. (2004) · Journal of the Science of Food and Agriculture · doi:10.1002/jsfa.1873 · Cited by 869
Huang, M., Smart, R. C., Wong, C.-Q., & Conney, A. H. (1988) · PubMed · Cited by 729
The Function of Tocopherols and Tocotrienols in Plants
Munné‐Bosch, S., & Alegre, L. (2002) · Critical Reviews in Plant Sciences · doi:10.1080/0735-260291044179 · Cited by 673
The Function of Tocopherols and Tocotrienols in Plants
Munné‐Bosch, S. (2002) · Critical Reviews in Plant Sciences · doi:10.1016/s0735-2689(02)80037-5 · Cited by 565
Enzymic and non-enzymic antioxidants in epidermis and dermis of human skin
Shindo, Y., Witt, E., Han, D., Epstein, W., & Packer, L. (1994) · Journal of Investigative Dermatology · doi:10.1111/1523-1747.ep12371744 · Cited by 546
Agar, N., Halliday, G. M., Barnetson, R. S., Ananthaswamy, H. N., Wheeler, M., & Jones, A. M. (2004) · Proceedings of the National Academy of Sciences · doi:10.1073/pnas.0401141101 · Cited by 536
Cited by
Sorted by citations
Antibacterial Activity and Mode of Action of Ferulic and Gallic Acids Against Pathogenic Bacteria
Borges, A. D. S., Ferreira, C., Saavedra, M. J., & Simões, M. V. (2013) · Microbial Drug Resistance · doi:10.1089/mdr.2012.0244 · Cited by 1,311
Potential applications of ferulic acid from natural sources
Kumar, N., & Pruthi, V. (2014) · Biotechnology Reports · doi:10.1016/j.btre.2014.09.002 · Cited by 965
Ganceviciene, R., Liakou, A. I., Theodoridis, A., Makrantonaki, E., & Zouboulis, C. C. (2012) · Dermato-Endocrinology · doi:10.4161/derm.22804 · Cited by 844
Photoageing: mechanism, prevention and therapy
Yaar, M., & Gilchrest, B. A. (2007) · British Journal of Dermatology · doi:10.1111/j.1365-2133.2007.08108.x · Cited by 755
The Roles of Vitamin C in Skin Health.
Pullar, J., Carr, A., & Vissers, M. (2017) · Nutrients · doi:10.3390/nu9080866 · Cited by 756
“Topical application of vitamin C, in combination with vitamin E and other compounds, has also been shown to reduce injury due to UV irradiation [50,54,65,89,150,152,153].”
Background
Metadata
- Authors
- Lin, F.-H., Lin, J.-Y., Gupta, R. D., Tournas, J. A., Burch, J. A., Angelica Selim, M., Monteiro-Riviere, N. A., Grichnik, J. M., Zielinski, J., & Pinnell, S. R.
- Affiliations
- Duke Medical Center (US)
- Chang Gung Memorial Hospital (TW)
- North Carolina State University (US)
- Corresponding author
- Pinnell, Sheldon R.
- Venue
- Journal of Investigative Dermatology
- Publisher
- Elsevier BV
- Published
- 2005-10
- Volume
- 125
- Issue
- 4
- Pages
- 826-832
- ISSN
- 0022-202X (ISSN-L)
- OpenAlex
- W2139034283
- Cited by
- 365
- References
- 45
- Citations by year
- 2026: 27 · 2025: 26 · 2024: 17 · 2023: 24 · 2022: 30 · 2021: 26 · 2020: 15 · 2019: 19 · 2018: 14 · 2017: 19 · 2016: 19 · 2015: 23 · 2014: 10 · 2013: 11 · 2012: 19
- FWCI
- 11.89
- Type
- journal article
- Language
- en
- Open access
- bronze
- doi.org
- Licence
- Locations
- Journal of Investigative Dermatology (publishedVersion)
- PubMed (publishedVersion)
- Funders
- National Institutes of Health (1r43ca083538-01a1)
- National Cancer Institute (R43 CA 83538)
- Topics
- Health Sciences › Medicine › Dermatology › Skin Protection and Aging
- Health Sciences › Medicine › Biochemistry (medical) › Phytochemicals and Antioxidant Activities
- Life Sciences › Biochemistry, Genetics and Molecular Biology › Cell Biology › melanin and skin pigmentation
- Keywords
- ferulic acid, vitamin C, vitamin E, topical antioxidants, photoprotection, skin, chemical stability, erythema, sunburn cells, apoptosis, caspase-3, caspase-7, thymine dimers, oxidative stress, photoaging, skin cancer prevention
- MeSH terms
- Animals, Ascorbic Acid, Coumaric Acids, Drug Stability, Radiation-Protective Agents, Swine, Ultraviolet Rays, Vitamin E, Skin Aging
About these checks
Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.
A language model drew the claims from the paper on 2026-10-31, under version 3 of the claim definition (model deepseek-v4.1-flash, prompt extract-v3).
A second model labelled each claim on 2026-10-31 (model jev-1.13-20260917, definition revision gold-guideline-v0.2).
Cited sources are checked with a language model’s help (gpt-6-sol).
Statistics and arithmetic are recomputed, not judged.
Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.
What counts as a claim ›How we measure confidence ›How we check this ›
Are you an author, or do you see a problem with this page? Request a review
