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Notes: The pineal hormone, melatonin exerts many functional effects on mammalian skin (e.g. melanogenesis inhibition, melanocyte growth inhibition, and regulation of seasonal pelage hair growth). However, its cutaneous expression, regulation, and functional role are still obscure. The aim of this study was to check whether murine hair follicles are indeed direct, peripheral melatonin targets which express melatonin membrane receptors (MT1 and MT2) and orphan nuclear receptor α (RORα) which interact with melatonin. Immunohistochemistry revealed that murine hair follicle keratinocytes show both MT1-like immunoreactivity (IR) and ROR-like IR, both of which changed substantially in a hair cycle-dependent manner. Both semiquantitive RT-PCR for MT1 and MT2, and quantitive real-time PCR for MT1, MT2, and ROR on murine skin cDNA revealed that all three genes are transcribed in normal mouse skin in hair cycle-dependent manner. Functionally, melatonin significantly inhibited the constitutional level of epidermal and hair follicle keratinocyte apoptosis in short-term mouse skin organ culture. In conclusion, we here provide evidence that normal murine hair follicles are prominent direct target for melatonin bioregulation which express MT1, MT2, and ROR, at least some of which are functionally active in situ. These receptors are regulated in a hair cycle-dependent manner, suggesting a role of melatonin in hair cycle control.

Notes: The hair follicle offers an exquisite model for the experimental exploration of key issues of cutaneous neuroimmunology, for example, how local, intracutaneous and systemic stress–response systems are integrated with the skin immune system and with epithelial–mesenchymal interactions (as they occur during hair follicle growth and cycling). Previously, we had shown that skin mast cells, which operate as central switchboards of inflammation and tissue remodelling, also are important regulators of hair growth in mice and that endogenous, immunomodulatory mast cell secretagogues are potent hair growth modulators. This is true both for secretagogues that are generated by the hair follicle epithelium itself (e.g. ACTH) and for mast cell-activating neuropeptides synthesized by the sensory hair follicle innervation (e.g. SP). Also, we had shown that the prototypic stress-associated neuropeptide, SP, plays a crucial role in mediating the hair growth-inhibitory, mast cell-activating, inflammation- and catagen-promoting properties of chronic psychoemotional stress on murine hair follicles. Now, we show that the immunomodulatory and mast cell-activating neurotrophin, NGF, is also crucially involved in mediating the inhibitory effects of stress on murine hair growth. Furthermore, the central, stress-related neurohormone CRH, a recognized mast cell secretagogue which is expressed by the hair follicle epithelium, also is a hair growth inhibitor and activates a fully functional peripheral equivalent of the hypothalamic-pituitary-adrenal axis within organ-cultured human scalp hair follicles, including the synthesis and secretion of cortisol as well as the induction of classical feedback loops. We also demonstrate that one of the melanocortins whose intrafollicular synthesis is stimulated by CRH (α-MSH) is a potent suppressor of MHC class I expression in situ and is thus capable of restoring the collapsed immune privilege of human anagen hair bulbs, while SP upregulates the ectopic expression of MHC class I, thus endangering the hair follicle immune privilege. Finally, we show that vanilloids long exploited as experimental tools for neuroimmunological research in the skin (capsaicin) can, in fact, directly modulate human hair growth via the stimulation of vanilloid receptors (VR1) expressed by the follicle epithelium, in addition to stimulating vanilloid expressed by skin mast cells. Therefore, the hair follicle offers an ideal, highly instructive and clinically most relevant research model for dissecting how nervous system, central and peripheral (neuro-) endocrine signalling loops and the immune system interact in order to adapt skin functions to changing environmental conditions (e.g. in response to external stressors, by alterating, e.g. keratinocyte proliferation/apoptosis, skin immune status, as well as defined cutaneous metabolic and endocrine activities).

Notes: : Changes of chicken breast myosin during storage at 2°C and 37°C were monitored immunochemically. Anti-myosin subfragment-1 (S-1) monoclonal antibody, which recognized epitopes within the 27 kDa fragment of S-1, and the anti-myosin rod polyclonal antiserum, were prepared. Myosin degradation products were not detected in muscle extracts stored for 3 weeks at 2°C. In contrast, storage at 37°C brought about the degradation of myosin heavy chain to immunologically detectable small fragments. While, myosin rod produced during the conditioning period was not decomposed into any small filaments. Namely, storage of muscle at 37°C resulted in minor amounts of myosin heavy chain degradation, with initial conversion to rod and S-1 fragments, and subsequent breakdown occurred in the S-1 region only. Immunoblot assay also suggested that the pattern of changes in myosin heavy chain in muscle incubated at 37°C was similar to that produced by in vitro digestion with cathepsin D.

Notes: : Changes of proteins in beef cubes, soup stock, and scum (a complex of coagulated proteins, fat, and minerals floating on soup stock) during simmering in sub-boiling water at 95 °C for 3 h were investigated by SDS-PAGE and Western blotting. Of the soluble proteins in soup stock heated for 1 h, 3 components having molecular weights between 47 and 36 kDa reacted with myosin antibody. Those bands disappeared from soup stock after heating for 3 h, however, they were observed in the scum. Bands of 70 and 58 kDa, which reacted with myosin antibody and were observed after 1 h of heating at 95 °C, were also observed after 30 min of heating under pressure.

Notes: Water (H2 15O) translocation from the roots to the top of rice plants (Oryza saliva L. cv. Nipponbare) was visualized over time by a positron-emitting tracer imaging system (PETIS). H2 15O flow was activated 8 min after plants were exposed to bright light (1 500 μmol m−2 s−1). When the light was subsequently removed, the flow gradually slowed and completely stopped after 12 min. In plants exposed to low light (500 μmol m−2 s−1), H2 15O flow was activated more slowly, and a higher translocation rate of H2 15O was observed in the same low light at the end of the next dark period. NaCl (80 mM) and methylmercury (1 mM) directly suppressed absorption of H2 15O by the roots, while methionine sulfoximine (1 mM), abscisic acid (10 μM) and carbonyl cyanide m-chlorophenylhydrazone (10 mM) were transported to the leaves and enhanced stomatal closure, reducing H2 15O translocation.