title: Zinc coadministration attenuates melatonin's effect on nitric oxide production in mice.
abstract: Both melatonin (MEL) and zinc (Zn) are considered beneficial for anti-immunosenescence. MEL's effects on immune functions are partly attributed to an interaction with Zn. However, the augmentation of or interference with MEL's effects by coadministration of Zn remains unclear. In this study, adult older mice received either MEL (10 microg/mL), Zn (22 microg/mL), MEL+Zn, or null supplementation from drinking water for 3 mo. The results showed that treated mice, irrespective of the type of added chemicals, had higher body-weight gain and body-fat content than control mice. MEL- and Zn-treated mice also had increased serum free fatty acid levels. In addition, the MEL group had decreased serum NOx (nitrite+nitrate) values. Serum tumor necrosis factor-alpha levels were increased, although nonsignificantly, in mice that received either MEL or Zn supplementation. However, the differences described were not retained in the mice that received MEL+Zn treatment. We conclude that a high-dose Zn coadministration might exert negative influences on MEL's regulatory effects, at least on nitric oxide production.
authors.affiliation: Department of Internal Medicine, Taichung Veterans General Hospital, Republic of China.
authors.forename: M D
authors.initials: MD
authors.lastname: Chen
authors.forename: P Y
authors.initials: PY
authors.lastname: Lin
authors.forename: W H
authors.initials: WH
authors.lastname: Sheu
mesh_terms: D000273:Adipose Tissue / Q000187:drug effects; D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D001835:Body Weight / Q000187:drug effects; D005230:Fatty Acids, Nonesterified / Q000097:blood; D008297:Male; D008550:Melatonin / Q000008:administration & dosage / Q000494:pharmacology*; D051379:Mice; D008810:Mice, Inbred C57BL; D009569:Nitric Oxide / Q000096:biosynthesis* / Q000097:blood; D014280:Triglycerides / Q000097:blood; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism; D015032:Zinc / Q000008:administration & dosage / Q000097:blood / Q000494:pharmacology* / Q000652:urine
chemical_list: D001786:Blood Glucose; D005230:Fatty Acids, Nonesterified; D014280:Triglycerides; D014409:Tumor Necrosis Factor-alpha; D009569:Nitric Oxide; D015032:Zinc; D008550:Melatonin