ABSTRACT
Elastic fibers in the dermis play an important role in skin elasticity. The desmosine crosslinking structure constructed of lysyl oxidase (LOX) in elastic fibers contributes to elasticity, while elastic fibers are primarily degraded by one of the matrix metalloproteinases (MMPs), MMP-12. We investigated the gender differences and diurnal variation of these enzymes. Gender-based differences in LOX mRNA expression were detected, and were significantly lower in females. In contrast, higher MMP-12 mRNA expression was observed in the light period, suggesting that elastic fibers might be degraded in the light rather than the dark period.
Subject(s)
Gene Expression Regulation, Enzymologic , Matrix Metalloproteinase 12/genetics , Protein-Lysine 6-Oxidase/genetics , Skin/metabolism , Animals , Circadian Rhythm/genetics , Female , Male , Mice , RNA, Messenger/genetics , RNA, Messenger/metabolism , Sex CharacteristicsABSTRACT
Depression is a pathological state of mood and is considered as one of the major causes of disabilities. Thus, the prevention of depression and care for individuals with depression is important. In the present study, we examined whether a single oral dose of CBEX (chicken breast extract), or carnosine (one of the major components of CBEX) affects immobility time, an index of depressive-like behavior, in the forced swimming test in male Wistar rats. CBEX tended to (P=0.09) and carnosine significantly (P<0.05) decreased immobility time in the forced swimming test. In the hippocampus, both CBEX and carnosine significantly decreased 3-methoxy-4-hydroxyphenylglycol, a major metabolite of norepinephrine, indicating that CBEX and carnosine could reduce NE activity in the hippocampus in the forced swimming test. CBEX and carnosine did not affect total locomotive distance or rearing in the open field test, suggesting that the reductions of immobility time by both treatments in the forced swimming test were not merely due to the stimulation of general motor activity. Taken together, these results suggest that CBEX has an antidepressant-like effect, which may be due, in part, to the effect of carnosine.
Subject(s)
Antidepressive Agents/pharmacology , Carnosine/pharmacology , Animals , Behavior, Animal/drug effects , Biogenic Monoamines/metabolism , Chickens , Depression/drug therapy , Depression/physiopathology , Depression/psychology , Hippocampus/drug effects , Hippocampus/metabolism , Hypothalamus/drug effects , Hypothalamus/metabolism , Male , Methoxyhydroxyphenylglycol/metabolism , Motor Activity/drug effects , Norepinephrine/metabolism , Rats , Rats, WistarABSTRACT
We attempted to develop a method to determine easily and effectively the degree of postmortem aging of pork longissimus dorsi (LD) by measuring the activity of proteases in the LD using fluorogenic peptide substrates. LD was used to measure the change with time in the protease activity detected with these substrates. Determining the variations within the LD muscles, strong positive correlations were found between changes in hardness and fluorescence intensities against Ac-Ala-MCA, Ac-Met-MCA, Ac-Ser-MCA, Ac-Thr-MCA, and Ac-Ala-Phe-MCA (P<0.005), and strong negative correlations were found between changes in total amounts of free amino acids and Ac-Ala-MCA, Ac-Met-MCA, Ac-Ser-MCA, Ac-Thr-MCA, and Ac-Ala-Phe-MCA (P<0.001). Negative correlations were also observed between changes in the amounts of free Ala, Arg, Lys, Leu, Met, Phe, and Tyr and the fluorescence intensities against Ala, Arg, Lys, Leu, Met, Phe, and Tyr-MCA respectively (P<0.001).
