Table 1. Summary of the Biochemical Pathways and Compounds altered in sun-exposed sites.

Pathway	Compounds	Ratio	p-value
Purine Metabolism pathway	Inosine	Increased	0.03
	Xanthine	Increased	0.04
	Hypo-xanthine	Increased	0.04
	Uric acid	Increased	0.01
	Adenosine	Decreased	0.02
	Guanosine	No change
Methionine and glutathione Metabolism pathway	S-adenosylhomocysteine	Increased	<0.001
	Cysteine	Increased	<0.001
	Reduced glutathione	Decreased	0.002
	Cysteine-glutathione disulphide	Increased	<0.001
	Glycine	No change
	Glutamate	No change
	Gamma-methyl ester	Decreased	0.01
	gamma-glutamylvaline	Decreased	<0.001
	gamma-glutamylleucine	Decreased	<0.001
	gamma-glutamylisoleucine	Decreased	0.03
	gamma-glutamylglutamate	Decreased	0.001
	gamma-glutamylphenylalanine	Decreased	<0.001
	gamma-glutamyltyrosine	Decreased	<0.001
Nicotinamide Metabolism pathway	Nicotinamide	Increased	0.05
	Nicotinamide ribonucleotide	Increased	0.02
	Nicotine riboside	Increased	0.05
	Quinolinic acid	Not found
	Nicotinic acid	Not found
	Mononucleotide	Not found
	Nicotinamide adenine dinucleotide	No change

Increased: The metabolites were up-regulated in biopsies from sun-exposed skin.

Decreased: The metabolites were down-regulated in biopsies from sun-exposed skin.