We investigated the cutaneous expression of genes and enzymes responsible for the multistep conversion of tryptophan to serotonin and further to melatonin. Samples tested were human skin, normal and pathologic (basal cell carcinoma and melanoma), cultured normal epidermal and follicular melanocytes, melanoma cell lines, normal neonatal and adult epidermal and follicular keratinocytes, squamous cell carcinoma cells, and fibroblasts from dermis and follicular papilla. The majority of the samples showed simultaneous expression of the genes for tryptophan hydroxylase, arylalkylamine N-acetyltransferase (AANAT), and hydroxyindole-O-methyltransferase (HIOMT). The products of AANAT activity were identified by RP-HPLC with fluorimetric detection in human skin and in cultured normal and malignant melanocytes and immortalized keratinocytes; HIOMT activity was detected in human skin, keratinocytes, and melanoma cells. N-acetylserotonin (NAS) was detected by RP-HPLC in human skin extracts. NAS identity was confirmed further by LC/MS in keratinocytes. In conclusion, we provide evidence that the human skin expresses intrinsic serotonin and melatonin biosynthetic pathways.

No abstract

No abstract

Background-Cardiovascular disease has become the leading cause of death in China. We examined the levels of serum total and lipoprotein cholesterol and status of awareness, treatment, and control of hypercholesterolemia in China. Methods and Results-A cross-sectional survey in a nationally representative sample of 15 540 Chinese adults 35 to 74 years of age was conducted during 2000 to 2001. Serum cholesterol was measured by use of standard methods, and information on treatment of hyperlipidemia was obtained by use of a standard questionnaire. Age-standardized mean levels of total, HDL, and LDL cholesterol and triglycerides were 186.1, 51.7, 109.5, and 128.1 mg/dL, respectively. Of the Chinese population 35 to 74 years of age, 23.8% (112 500 000 persons) had borderline high total cholesterol (200 to 239 mg/dL), and 9.0% (42 540 000 persons) had high total cholesterol (Ն240 mg/dL). The population estimates for borderline high (130 to 159 mg/dL), high (160 to 189 mg/dL), and very high (Ն190 mg/dL) LDL cholesterol were 17.0% (80 122 000 persons), 5.1% (24 329 000 persons), and 2.7% (12 822 000 persons), respectively. In addition, 19.2%, or 90 803 000 persons, had a low HDL cholesterol (Ͻ40 mg/dL). Among those who had a total cholesterol Ն200 mg/dL or who were on cholesterol-lowering medications, the proportion of men and women who were aware, treated, and controlled was only 8.8% and 7.5%, 3.5% and 3.4%, and 1.9% and 1.5%, respectively. Conclusions-The prevalence of hypercholesterolemia was relatively high and the percentage of adults with controlled blood cholesterol was low in China. Prevention and treatment of hypercholesterolemia should be an important component of a national strategy to reduce the substantial and increasing burden of cardiovascular disease in China.