16-Androstenes, or androst-16-enes, are a class of

endogenous Endogeny, in biology, refers to the property of originating or developing from within an organism, tissue, or cell. For example, ''endogenous substances'', and ''endogenous processes'' are those that originate within a living system (e.g. an ...

androstane Androstane is a C19 steroidal hydrocarbon with a gonane core. Androstane can exist as either of two isomers, known as 5α-androstane and 5β-androstane. File:androstane.png, 5α-Androstane File:androstane 5beta.png, 5β-Androstane Pharmacolog ...

steroid A steroid is an organic compound with four fused compound, fused rings (designated A, B, C, and D) arranged in a specific molecular configuration. Steroids have two principal biological functions: as important components of cell membranes t ...

s that includes

androstadienol Androstadienol, or androsta-5,16-dien-3β-ol, is a 16-androstene class endogenous steroid, pheromone, and chemical intermediate to several other pheromones that is found in the sweat of both men and women. Androstadienol and androstadienone ...

androstadienone Androstadienone, or androsta-4,16-dien-3-one, is a 16-androstene class endogenous steroid that has been described as having potent pheromone-like activities in humans. The compound is synthesized from androstadienol by 3β-hydroxysteroid dehyd ...

androstenone Androstenone (5α-androst-16-en-3-one) is a 16-androstene class steroidal pheromone. It is found in boar's saliva, celery cytoplasm, and truffle fungus. Androstenone was the first mammalian pheromone to be identified. It is found in high concen ...

, and

androstenol Androstenol, also known as 5α-androst-16-en-3α-ol (shortened to 3α,5α-androstenol or 3α-androstenol), is a 16-androstene class steroidal pheromone and neurosteroid in humans and other mammals, notably pigs. It possesses a characteristic mu ...

, which are

pheromone A pheromone () is a secreted or excreted chemical factor that triggers a social response in members of the same species. Pheromones are chemicals capable of acting like hormones outside the body of the secreting individual, to affect the behavio ...

s. Some of the 16-androstenes, such as androstenone and androstenol, are odorous, and have been confirmed to contribute to human malodor.

Background

The 16-Androstene steroid is most commonly found and produced in

boar The wild boar (''Sus scrofa''), also known as the wild swine, common wild pig, Eurasian wild pig, or simply wild pig, is a Suidae, suid native to much of Eurasia and North Africa, and has been introduced to the Americas and Oceania. The speci ...

testicle, specifically in un-castrated male pigs, which results in a foul odor. This foul odor typically has a

urine Urine is a liquid by-product of metabolism in humans and many other animals. In placental mammals, urine flows from the Kidney (vertebrates), kidneys through the ureters to the urinary bladder and exits the urethra through the penile meatus (mal ...

-like or

skatole Skatole or 3-methylindole is an organic compound belonging to the indole family. It occurs naturally in the feces of mammals and birds and is the primary contributor to fecal odor. In low concentrations, it has a flowery smell and is found in sever ...

odor which is as a result of high concentration and levels of the 16-Androstene steroid found in the boar's

Adipose tissue Adipose tissue (also known as body fat or simply fat) is a loose connective tissue composed mostly of adipocytes. It also contains the stromal vascular fraction (SVF) of cells including preadipocytes, fibroblasts, Blood vessel, vascular endothel ...

, that is observed when the boar fat is cooked on heat. The 16-Androstene acts as a

which is transported in a boar's body through the bloodstream to the

salivary gland The salivary glands in many vertebrates including mammals are exocrine glands that produce saliva through a system of ducts. Humans have three paired major salivary glands ( parotid, submandibular, and sublingual), as well as hundreds of min ...

s and is metabolized in the

liver The liver is a major metabolic organ (anatomy), organ exclusively found in vertebrates, which performs many essential biological Function (biology), functions such as detoxification of the organism, and the Protein biosynthesis, synthesis of var ...

which produces alpha and beta-androstenol. The reason why the 16-Androstene steroid is essential in the overall population of boars is because it plays a vital role in the mating process, specifically attracting gilts. The 16-Androstene steroid is a vital steroid to study in order to better understand varying

gene In biology, the word gene has two meanings. The Mendelian gene is a basic unit of heredity. The molecular gene is a sequence of nucleotides in DNA that is transcribed to produce a functional RNA. There are two types of molecular genes: protei ...

s and metabolic pathways and its relation to the similarities and differences observed in human axillary odors.

Research Findings

The 16-Androstene steroid is a compound of interest in various research relating to the topic of steroid-based malodour. Most of the research conducted on the 16-Androstene steroid is done by experimentation of boars, often looking at various

metabolic pathway In biochemistry, a metabolic pathway is a linked series of chemical reactions occurring within a cell (biology), cell. The reactants, products, and Metabolic intermediate, intermediates of an enzymatic reaction are known as metabolites, which are ...

s and

genetics Genetics is the study of genes, genetic variation, and heredity in organisms.Hartl D, Jones E (2005) It is an important branch in biology because heredity is vital to organisms' evolution. Gregor Mendel, a Moravian Augustinians, Augustinian ...

which are similar and different in varying breeds of boars. These studies are conducted in order to utilize the research conducted on boars to better understand human axillary odors. Research conducted by Gower in 1994 suggested that the 16-Androstene along with other steroids such as the 5α-androstenol and 5α-androstenone, are prevalent in

apocrine sweat gland An apocrine sweat gland (; from Greek ''apo'' 'away' and ''krinein'' 'to separate') is composed of a coiled secretory portion located at the junction of the dermis and subcutaneous fat, from which a straight portion inserts and secretes into th ...

s. Later research by Austin and Ellis in 2003 revealed through the use of

mass spectrometry Mass spectrometry (MS) is an analytical technique that is used to measure the mass-to-charge ratio of ions. The results are presented as a ''mass spectrum'', a plot of intensity as a function of the mass-to-charge ratio. Mass spectrometry is used ...

(MS) and

gas chromatography Gas chromatography (GC) is a common type of chromatography used in analytical chemistry for Separation process, separating and analyzing compounds that can be vaporized without Chemical decomposition, decomposition. Typical uses of GC include t ...

(GC), that the 16-Androstene steroid was present on axillary skin which determined that axillary bacteria are able to create 16-androstenes steroids from the bacteria that had the C16

double bond In chemistry, a double bond is a covalent bond between two atoms involving four bonding electrons as opposed to two in a single bond. Double bonds occur most commonly between two carbon atoms, for example in alkenes. Many double bonds exist betw ...

already present. Other research indicates that 3

eta Eta ( ; uppercase , lowercase ; ''ē̂ta'' or ''ita'' ) is the seventh letter of the Greek alphabet, representing the close front unrounded vowel, . Originally denoting the voiceless glottal fricative, , in most dialects of Ancient Greek, it ...

hydroxysteroid dehydrogenase (3

HSD) plays a vital role in the metabolism of

. When looking at the adipose tissue of a boar, it was also observed that there were high levels of androstenone when there was a low expression of

enzyme An enzyme () is a protein that acts as a biological catalyst by accelerating chemical reactions. The molecules upon which enzymes may act are called substrate (chemistry), substrates, and the enzyme converts the substrates into different mol ...

protein Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residue (biochemistry), residues. Proteins perform a vast array of functions within organisms, including Enzyme catalysis, catalysing metab ...

and

mRNA In molecular biology, messenger ribonucleic acid (mRNA) is a single-stranded molecule of RNA that corresponds to the genetic sequence of a gene, and is read by a ribosome in the process of Protein biosynthesis, synthesizing a protein. mRNA is ...

showing a negative trend. Additionally, some research indicates that the presence of the 16-Androstene steroid contributes significantly to the role and function of the liver which is to participate in phase II conjugation metabolism. These were some of the research findings from various articles illustrating the role that the 16-Androstene steroid plays in metabolic pathways and genetics. All of these research findings are able to assist in better understanding

s, metabolic pathways, and enzymes which will aid in scientists understanding how to diminish boar taint / odor.

Research Methods

A variety of research methods were utilized in multiple research articles to gather vital information on the 16-Androstene steroid. Methods such as PCR,

(MS),

(GC), solid-phase chromatography, microarray technology, and various other methods were utilized in the research articles to understand the 16-Androstene steroid.

References

{{DEFAULTSORT:Androstene, 16- Androstanes Neurosteroids Pheromones

Background

Research Findings

Research Methods

See also

References