Pheromone steroid

Booth, W.D. and White, C.A. (1988) The isolation, purification and some properties of phero-maxin, the pheromonal steroid-binding protein, in porcine submaxillary glands and saliva. J. Endocrin. 118, 47-57. 

At the time of ovulation - which is about 12 hours after onset of the gonadotropin II surge in the female - females release less pheromonal steroids than before. They now become sexually active, receptive, and attractive to males. 

Claus, R. and Hoppen, H.O. 1979. The boar pheromone steroid identified in vegetables. Experentia 35(12), 1674. 

Valuable as the method is, it is limited in that important odorants, such as the pig pheromone steroids, lack sufficient volatility to register in such a profile. In addition, the odor thresholds of different volatile compounds vary over a very wide range so that trace components may dominate the perceived odor (Buttery et al., 1969). Also, the relative proportions of the components registered is heavily dependent on the experimental procedure used (Jennings and Filsoof, 1977) so that interest surrounds variations in profiles obtained under identical analytical conditions. 

Zheng, W.B., Strobeck, C., and Stacey, N. (1997). The steroid pheromone 4-pregnen-17 alpha, 20 beta-diol-3-one increases fertility and paternity in goldfish. Journal of Experimental Biology 200, 2833-2840. 

Two illustrations that show the power of this reaction for the preparation of strained cycloalkenes are the contractions of 102 to the propellane 103 , an application that has been reviewed , and of 104 to the bicyclo[2.1.1]hexene 105 . The utility of the Ramberg-Backlund rearrangement in the preparation of various natural products such as steroids , terpenoids and pheromones has been demonstrated. In addition to the synthetic applications mentioned in the previous subsection, several selected examples taken from the recent literature are given in equations 66-69. These examples further demonstrate the potential of this method for alkene synthesis in general. 

Evidence has been accumulating that extracellular metabolic activity of microorganisms, mainly bacteria, occurs within skin glands and on the skin surface (Albone, 1997). Sterile human apocrine secretions do not develop the characteristic axillary odour (Shelley et al., 1953). In the salivary secretions of the boar, transformations of the pheromonal 16-androstene steroids 2. were attributed to the microbial flora (Booth, 1987). 

Adams M., Teeter J.H., Katz Y. and Johnsen P.B. (1987). Sex pheromones of the sea lamprey steroid studies on urinary products. J Chem Ecol 13, 387-395. 

Sorensen P.W., Hara T.J., Stacey N.E. and Dulka J.G. (1990). Extreme olfactory specificity of male goldfish to the preovulatory steroidal pheromone-17a20p-dihydroxy-4-pregnen-3-one. J Comp Physiol (A) 166, 373-383. 

Swann J. and Fiber J. (1997). Sex differences in function of a pheromonally stimulated pathway role of steroids and the main olfactory system. Brain Res Bull 44, 409-413. 

Bark beetles primarily utilize isoprenoid derived pheromones [100,101] and have been the most studied regarding their biosynthesis [8,98]. Earlier work indicated that the isoprenoid pheromones could be produced by the beetle altering host derived isoprenoids however more recent work indicates that for the most part bark beetles are producing pheromones de novo. The production of isoprenoids follows a pathway outlined in Fig. 4 which is similar to the isoprenoid pathway as it occurs in cholesterol synthesis in mammals. Insects cannot synthesize cholesterol but can synthesize farnesyl pyrophosphate. Insects apparently do not have the ability to cyclize the longer chain isoprenoid compounds into steroids. The key enzymes in the early steps of the isoprenoid... 

Cowley, J. J. and Brooksbank, B. W. L. (1991) Human exposure to putative pheromones and changes in aspects of social behaviour. J. Steroid Biochem. 39, 647-659. 

Monti-Bloch, L. and Grosser, B. I. (1991) Effect of putative pheromones on the electrical activity of the human vomeronasal organ and olfactory epithelium. J. Steroid Biochem. 39, 573-582. 

Pause, B. M. (2004) Are androgen steroids acting as pheromones in humans Physiol. Behav. 83, 21-29. 

Hudson, R., Gonzalez-Mariscal, G. and Beyer, C. (1990) Chin marking behavior, sexual receptivity, and pheromone emission in steroid-treated, ovariectomized rabbits. Hormones Behav. 24, 1-13. 

Not only the sensitivity of the human olfactory system to androstenol (5a-androst-16-en-3a-ol) and androstenone (5a-androst-16-en-3-one),but also the difference in the sensitivity with which individuals can detect these compounds and the fact that they are implicated in the semiochemical communication of the pig, Sus scrofa [166,167], have led to them being considered human pheromones. Final confirmation that they are human pheromones is still outstanding. However, it was recently found that passive inhalation of another related steroid, androsta-4,16-dien-3-one, can influence the physiological state of humans by increasing a positive mood in test persons [168]. It has yet to be determined whether humans exude concentrations of this chemical information that are adequate for communication within social contexts. 

In some cases, commercial use has been made of reproductive pheromonal effects. For example, spraying sows with synthetic 5a-androstenone, a steroid sold under the trade name Boar Mate, helps to ready the animal for mating with a boar. 5a-Androstenone is one of two steroids in the saliva of the boar that primes the sow for mating. 

In contrast to the evidence for primers, signalers, and modulators, there is no decent evidence to suggest that there are human releaser pheromones. That is not to argue that there are none but to state that there is no evidence for them at present. Nonetheless, products purported to be human releaser pheromones—specifically sex attractants—are widely available on the Internet. They go by such suggestive names as Scent of Eros, The Edge, Alter-ego, and Pheromone Additive. Many of these products contain either androstenone or androstenol, steroids of unknown influence on the human emotional state. 

It is important to identify and measure the concentrations of a number of compounds in a mixture simultaneously for several reasons. First, among related compounds there may exist precursors of active ones, and pathways of pheromone synthesis may be elucidated. This is true for steroids in the human axilla. Nixon etal. (1988) determined the concentration of five steroids extracted from axillary hair of adult men aged 18 to 40 years. The relationships in concentrations between the two ketones 5Q -androst-16-en-3-one and 4,16-androstadien-3-one suggest that axillary bacteria reduce the former to the latter with the aid of the enzyme 4-ene-5a-reductase. Humans have a low olfactory threshold for several 16-androstenes, and the fact that some men have large quantities of 16-androstenes (Nixon etal., 1988) is biologically suggestive. 

All male fish pheromones are steroidal (Sorensen and Stacey, 1990). Many male fish release chemicals that attract females, stimulate them to spawn, and inhibit their aggression. As early as 1982, Liley compiled a long list of examples testes, as in goldfish (Stacey and Hourston, 1982), urogenital fluid, glands on the caudal peduncle (an anal fin appendage), mucus and urine, can be sources of male pheromones. 

The well-known boar pheromone was not only one of the first mammalian pheromones identified, but also the first one applied commercially. The saliva from the submaxillaiy gland contains two steroids. These are 5a-androst-16-en-3-one and So -androst-lS-en-So -ol (Fig. 7.8). They are emitted during head-to-head contact in courtship. Both individually stimulate the sow to assume the mating stance, but a mixture of the two is not more active than either compound (Melrose etal., 1971). This may be a case of adaptive redundancy. 

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