Limits...
Importance of amino acid composition to improve skin collagen protein synthesis rates in UV-irradiated mice.

Murakami H, Shimbo K, Inoue Y, Takino Y, Kobayashi H - Amino Acids (2011)

Bottom Line: The FSR of dermal tropocollagen was measured 30 min after a single oral administration of amino acids (1 g/kg) to groups of 5-16 UVB-irradiated mice.Branched-chain amino acids (BCAA, 1.34±0.32), arginine (Arg, 1.66±0.39), glutamine (Gln, 1.75±0.60), and proline (Pro, 1.48±0.26) did not increase the FSR of skin tropocollagen compared with distilled water, which was used as a control (1.56±0.30).However, essential amino acids mixtures (BCAA+Arg+Gln, BCAA+Gln, and BCAA+Pro) significantly increased the FSR (2.07±0.58, 2.04±0.54, 2.01±0.50 and 2.07±0.59, respectively).

View Article: PubMed Central - PubMed

Affiliation: Frontier Research Laboratories, Institute for Innovation, Ajinomoto Co., Inc, 1-1 Suzuki-cho, Kawasaki, 210-8681, Japan. hitoshi_murakami@ajinomoto.com

ABSTRACT
Skin collagen metabolism abnormalities induced by ultraviolet (UV) radiation are the major causes of skin photoaging. It has been shown that the one-time exposure of UV irradiation decreases procollagen mRNA expression in dermis and that chronic UV irradiation decreases collagen amounts and induces wrinkle formation. Amino acids are generally known to regulate protein metabolism. Therefore, we investigated the effects of UV irradiation and various orally administered amino acids on skin collagen synthesis rates. Groups of 4-5 male, 8-week-old HR-1 hairless mice were irradiated with UVB (66 mJ/cm2) twice every other day, then fasted for 16 h. The fractional synthesis rate (FSR; %/h) of skin tropocollagen was evaluated by incorporating L-[ring-2H5]-phenylalanine. We confirmed that the FSR of dermal tropocollagen decreased after UVB irradiation. The FSR of dermal tropocollagen was measured 30 min after a single oral administration of amino acids (1 g/kg) to groups of 5-16 UVB-irradiated mice. Branched-chain amino acids (BCAA, 1.34±0.32), arginine (Arg, 1.66±0.39), glutamine (Gln, 1.75±0.60), and proline (Pro, 1.48±0.26) did not increase the FSR of skin tropocollagen compared with distilled water, which was used as a control (1.56±0.30). However, essential amino acids mixtures (BCAA+Arg+Gln, BCAA+Gln, and BCAA+Pro) significantly increased the FSR (2.07±0.58, 2.04±0.54, 2.01±0.50 and 2.07±0.59, respectively). This result suggests that combinations of BCAA and glutamine or proline are important for restoring dermal collagen protein synthesis impaired by UV irradiation.

Show MeSH

Related in: MedlinePlus

SDS-PAGE and Western blot analysis of isolated skin tropocollagen fractions. Type I, III and VII collagen were identified using Western blot, and the purity of extracted collagen was confirmed. sd Standard protein, and TP tropocollagen
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC3351609&req=5

Fig1: SDS-PAGE and Western blot analysis of isolated skin tropocollagen fractions. Type I, III and VII collagen were identified using Western blot, and the purity of extracted collagen was confirmed. sd Standard protein, and TP tropocollagen

Mentions: Skin tropocollagen extracted from the dorsal skin was assayed with Western blotting to confirm its purity. The protein bands of extracted skin tropocollagen separated by SDS-PAGE corresponded to Type I, III, and VII collagen bands (Fig. 1). The purity of the extraction was confirmed as described in a previous article (Volpi et al. 2000).Fig. 1


Importance of amino acid composition to improve skin collagen protein synthesis rates in UV-irradiated mice.

Murakami H, Shimbo K, Inoue Y, Takino Y, Kobayashi H - Amino Acids (2011)

SDS-PAGE and Western blot analysis of isolated skin tropocollagen fractions. Type I, III and VII collagen were identified using Western blot, and the purity of extracted collagen was confirmed. sd Standard protein, and TP tropocollagen
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3351609&req=5

Fig1: SDS-PAGE and Western blot analysis of isolated skin tropocollagen fractions. Type I, III and VII collagen were identified using Western blot, and the purity of extracted collagen was confirmed. sd Standard protein, and TP tropocollagen
Mentions: Skin tropocollagen extracted from the dorsal skin was assayed with Western blotting to confirm its purity. The protein bands of extracted skin tropocollagen separated by SDS-PAGE corresponded to Type I, III, and VII collagen bands (Fig. 1). The purity of the extraction was confirmed as described in a previous article (Volpi et al. 2000).Fig. 1

Bottom Line: The FSR of dermal tropocollagen was measured 30 min after a single oral administration of amino acids (1 g/kg) to groups of 5-16 UVB-irradiated mice.Branched-chain amino acids (BCAA, 1.34±0.32), arginine (Arg, 1.66±0.39), glutamine (Gln, 1.75±0.60), and proline (Pro, 1.48±0.26) did not increase the FSR of skin tropocollagen compared with distilled water, which was used as a control (1.56±0.30).However, essential amino acids mixtures (BCAA+Arg+Gln, BCAA+Gln, and BCAA+Pro) significantly increased the FSR (2.07±0.58, 2.04±0.54, 2.01±0.50 and 2.07±0.59, respectively).

View Article: PubMed Central - PubMed

Affiliation: Frontier Research Laboratories, Institute for Innovation, Ajinomoto Co., Inc, 1-1 Suzuki-cho, Kawasaki, 210-8681, Japan. hitoshi_murakami@ajinomoto.com

ABSTRACT
Skin collagen metabolism abnormalities induced by ultraviolet (UV) radiation are the major causes of skin photoaging. It has been shown that the one-time exposure of UV irradiation decreases procollagen mRNA expression in dermis and that chronic UV irradiation decreases collagen amounts and induces wrinkle formation. Amino acids are generally known to regulate protein metabolism. Therefore, we investigated the effects of UV irradiation and various orally administered amino acids on skin collagen synthesis rates. Groups of 4-5 male, 8-week-old HR-1 hairless mice were irradiated with UVB (66 mJ/cm2) twice every other day, then fasted for 16 h. The fractional synthesis rate (FSR; %/h) of skin tropocollagen was evaluated by incorporating L-[ring-2H5]-phenylalanine. We confirmed that the FSR of dermal tropocollagen decreased after UVB irradiation. The FSR of dermal tropocollagen was measured 30 min after a single oral administration of amino acids (1 g/kg) to groups of 5-16 UVB-irradiated mice. Branched-chain amino acids (BCAA, 1.34±0.32), arginine (Arg, 1.66±0.39), glutamine (Gln, 1.75±0.60), and proline (Pro, 1.48±0.26) did not increase the FSR of skin tropocollagen compared with distilled water, which was used as a control (1.56±0.30). However, essential amino acids mixtures (BCAA+Arg+Gln, BCAA+Gln, and BCAA+Pro) significantly increased the FSR (2.07±0.58, 2.04±0.54, 2.01±0.50 and 2.07±0.59, respectively). This result suggests that combinations of BCAA and glutamine or proline are important for restoring dermal collagen protein synthesis impaired by UV irradiation.

Show MeSH
Related in: MedlinePlus