Collagen aging

UV-B causes sunburn, but UV-A damages collagen (connective tissue) and blood vessels, causing aging effects such as wrinkled skin. 

The fifteen samples analyzed for amino acid composition were compared to a human type 1 collagen standard. There are no significant differences in amino acid composition among these samples, which range in age from stillbirth to adult. Analytical error is 10%. All samples show the typical composition of type 1 collagen (Table 1.1). Based on these results there is no reason to suspect differential preservation of specific amino acids in the small bones of infants in comparison to bones of adults and older children. 

Tabic 1.1. Amino acids per thousand residues for standard type 1 collagen and 15 human bone collagen samples from St. Thomas Church cemetery. Samples are identified by burial numlter (Bx) followed by age midpoint for subadults and age range for adults in parentheses. For example, B17(0) refers to burial 17 who was aged as a newborn. 

Table 1.3. 5 C%is and 5 N%o mean values and standard deviations (s.d.) for human bone collagen by age group.

Decreases in muscle and increases in hair and collagen 6 N with age were observed in litters raised on 20% protein. These results provide partial support for the hypothesis of a relationship between and age. 

Figure 12.1. Relationship between collagen 8 N values and age of male and female rats raised on controlled diets, and sacrificed at 40 day intervals beginning 91 days after birth.

The mean difference between collagen and flesh (A Nco.f) values for the first sacrificed pairs (91 days after birth) is 0.3 1.09%o while that for third pairs (171 days after birth) is 1.4 0.45%o. This result was unanticipated but seems robust. This indicates the relationship between diet and tissue 8 N and age is complex and varies between tissues. Future studies of diet-tissue nitrogen isotope spacing will have to consider age effects. This contrasts with carbon isotopes (Ambrose and Norr 1993), where we have observed little increase in 8 C with age in the same individuals. 

Figure 12.4. Relationship between rat weanling and adult collagen 5 N values. Weanlings and adult ages are 21 and 91 to 251 days old, respectively.

Eluorescence of both collagen (Monnier etal., 1986) and IgG (Jones etal., 1988) are associated with diabetic micrOangiopathy. Monnier etal. (1986) found that measured collagen-linked fluorescence in skin biopsies from both patients with type 1 diabetes ( = 41, age range 29-52 years) and controls ( =25, age range 28-41 years) was significantly correlated with the severity of retinopathy as well as arterial and joint stifihess. Jones et al. (1988) found increased fluorescence of serum IgG in diabetic patients with... 

Gillard, R. D., A. M. Pollard, R. A. Sutton, and D. K. Whittaker (1990), An improved method for age at death determination from the measurement of D-aspartic acid in dental collagen, Archaeometry 32, 61-70. 

Castle Svihov Middle age Artificial stone Collagens... 

Castle Lemberk Middle age Stucco decoration Collagens... 

Chateau in Namest nad Middle age Artificial marble Collagens... 

Figure 14.15 Comparison of bulk collagen and individual amino acid 813C values for high marine protein, C3 and C4 consumer later Stone Age humans from the Western Cape of South Africa (adapted from Corr et at. 2005)...

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