Sunday, January 31, 2016

On the Existence of Human Pheromones

            A fictionalized version of Hank Walter, the former chairman of International Flavors & Fragrances, Inc. (IFF), is portrayed by actor Josh Charles on Season 2 of the Showtime series Masters of Sex. IFF was (and continues to be) a massive global conglomerate that provided the chocolate flavor in Cocoa Puffs, as well as scents for the foremost perfume makers of the time. IFF and other private food and fragrance companies provided grant money to Masters and Johnson’s clinic to develop a pheromonal perfume and this collaboration served as a major plotline in Season 2 of the dramatic series. The fictional Walter character, ‘Dan Logan,’ conducts research on the show (See Figure above, left panel) aimed at marketing a natural aphrodisiac-infused scent to the general public. This led me to wonder: What is the deal with human pheromones? Have we actually identified smells (volatile molecules) that affect human behavior or is this junk pseudoscience propagated by the perfume industry? It turns out that the answer is: Yes, we have certainly identified olfactory signaling molecules that seem to influence our behavior. And the putative pheromone structures are steroids.
            Pheromones were first described in 1959 as airborne chemosignal molecules that convey information and produce behavioral, neuroendocrine or developmental changes in members of the same species. Olfactory chemical communication is ubiquitous in the animal kingdom but, until recently, was not believed to extend to human behavior and social interaction. However, contemporary studies describing the gender-specific psychological and physiological effects of two human steroids contradict this notion. The two specific putative pheromones are androsta-4,16-dien-3-one and estratetraenol (structures displayed below), from the general steroid class referred to as 16-androstenes. These are steroidal molecules that lack an oxygen atom at C17, which is required for androgenic or estrogenic activity.
            A 2014 study led by Wen Zhou at the Chinese Academy of Sciences (Beijing) aimed to determine whether or not the above-mentioned steroids communicate gender in a sex-specific manner. The authors showed that smelling androstadienone biases heterosexual females, but not males, toward perceiving images of walkers as more masculine. Moreover, exposure to estratetraenol odor was found to bias heterosexual males toward perceiving the walkers as more feminine. The results provide direct evidence that the two steroids communicate opposite gender information with the larger implication of the work being that human visual gender perception draws on chemosensory biological cues. Those chemosensory cues can be considered pheromones based on the definition that is referenced above. The intriguing results reported by Zhou and co-workers are consistent with previous findings that androstadienone increases cortisol levels and activates brain areas linked to social cognition. In addition to documented effects on human gender perception and physiology, there is also psychological evidence regarding androstadienone’s direct impact on male behavior. In a 2013 investigation conducted in Finland, androstadienone was found to increase cooperative behavior in decision-making tasks. Indeed, as a chemical signal of mate quality and dominance, the steroid elicited observable psychological effects on male subjects that seemed to place them in a socially subordinate position. Notably, this was the first study to show that androstadienone directly influences behavior in human males, acting in this instance as ‘the chemical equivalent of a peacock’s tail.’
            The 16-androstenes that have been identified in humans are biosynthesized from naturally occurring pregnenolone (see Scheme above). The biogenesis of the putative steroidal pheromones androstadienone and estratetraenol relies on the 16-ene-synthase activity of cytochrome P450 17A1 (CYP17A1), which excises the side chain subtituent from the enzymatic substrate and simultaneously installs the D16,17 double bond within the steroidal D-ring.
            It’s interesting to compare the structure of 5a-androst-16-en-3-one to the odorous macrocyclic ketone, civetone. Civetone is a known pheromone derived from African civet musk that is used in perfumery. When drawn in a somewhat biased fashion, key features of the two-dimensional structure of civetone are cleanly superimposed over the corresponding groups found in the A and D-rings of androstenone. The structural features responsible for a given odor have been referred to as ‘olfactophores’ or ‘odotypes.’ Androstenone happens to be the active ingredient in a commercial product called BoarmateTM, which, as one might gather from its name, was developed to assist farmers with swine breeding.
            In vertebrates, odors are sensed by members of a family of seven-transmembrane G-protein-coupled receptors called odorant or olfactory receptors (ORs) that are localized on the terminal knobs of olfactory sensory neurons (see Diagram below). The human receptor OR7D4 responds specifically to 16-androstenes including androstadienone and androstenone. Upon odorant binding, the OR undergoes a conformational change that activates an olfactory-specific subtype of G-protein. This triggers a downstream signaling cascade that ultimately leads to the nerve cell signal. Interestingly, perceptual variation in the intensity and pleasantness of certain odors has been shown to be dependent on the OR7D4 gene variant that an individual carries. The OR7D4 genotype also predicts the sensory perception of meat containing androstenone, which is consistent with the idea that genetic variation in this important OR can alter food preferences. Whether one chooses to believe in the existence of human pheromones or not, steroids clearly serve an essential olfactory signaling function that impacts broadly ranging aspects of the human condition from gender perception to social behavior to dietary choices.


  1. Wow great and amazing article. I have looking interesting articles for sample for making my article. Your blog is having wonderful article .

  2. OR undergoes a conformational change that activates an olfactory-specific subtype of G-protein.laptop repair nottingham

  3. You make so many great points here that I read your article a couple of times. Your views are in accordance with my own for the most part. This is great content for your readers.

  4. Healthtipsschool News reports on emerging research, new treatments, diet, exercise, and trending topics in health tips of the day and wellness. Get results with different meditation techniques. Variations in technique will allow you to tap into a greater number of physiological and psychological benefits.

  5. I find something in herbal medicine good to share on here with anyone suffering from the disease such as HIV, Herpes, Hepatitis or Chronic Lyme Disease,Parkinson's disease,Schizophrenia,Lung Cancer,Breast Cancer,Colo-Rectal Cancer,Blood Cancer,Prostate Cancer,siva.Fatal Familial Insomnia Factor V Leiden Mutation ,Epilepsy Dupuytren's disease,Desmoplastic small-round-cell tumor Diabetes ,Coeliac disease,Creutzfeldt–Jakob disease,Cerebral Amyloid Angiopathy, Ataxia,Arthritis,Amyotrophic Lateral Scoliosis,Fibromyalgia,Fluoroquinolone Toxicity
    Syndrome Fibrodysplasia Ossificans ProgresSclerosis,Seizures,Alzheimer's disease,Adrenocortical carcinoma.Asthma,Allergic diseases.Hiv_ Aids,Herpe ,Copd,Glaucoma., Cataracts,Macular degeneration,Cardiovascular disease,Lung disease.Enlarged prostate,Osteoporosis.Alzheimer's disease,
    Lupus as well.Dr Itua herbal made cure my HIV and gave me hope that he can cure all types of diseases I believed him) I do the best of myself that I can do, I went for a program in west Africa about fashion on another side I was HIV positive. I walk through a nearby village for our program schedule then I found a signage notice that says Dr Itua Herbal Center then I asked my colleagues what all about this very man called Dr Itua, She told me that he's a herbal doctor and he can cure all kind of disease i walked to him and explain myself to him as I'm a strangler out there he prepared me herbal medicine and told me how to drink it for two weeks, when I get to my hotel room I take a look at it then says a prayer before I drank it not knowing after two weeks I went to test and I found out I was negative I ran to him to pay him more but he refuses and says I should share his works for me around the globe so sick people can see as well. I'm writing a lot about him this season so that is how I was cured by drinking Dr Itua herbal medicine, He's A caring man with godly heart. Well - everything I decided all go through for me well and how you're going to treat this new aspect to your life. You don't have to suffer alone, and it's okay to ask for help. It also doesn't have to be a constant demon, as you'll get to know your body and yourself in a much deeper way than most people. Take advantage of this, as it will help you appreciate Africa Herbal Made.
    Dr Itua Contact Information.
    Whatsapp Number....+2348149277967

  6. buy alprazolam,ketamine,mdma,crystal meth,fentanyl at

    Order Fentanyl, Oxycodone , Xanax Bars , Percs , Roxicodone at low cost..With us , you get meds discreet with no prescription. We've worked to create a fast,
    efficient and fair system for order processing. We know you want your order quickly, at the lowest possible cost.Check some of our highly purchased meds;

    We are the best supplier of pain medications and research chemicals .our prices are affordable .
    For more details contact our website through any of the details provided below


    Call: +1 (925)-338-9583 (USA/Canada)

    whatsapp: +1 (925)-338-9583

    Link: Buy Amphetamine Powder online

    Link: Buy Pure Grade Heroin online

    Link: Buy Cocaine Powder online

    Link: Buy Herbal Incense for sale

  7. Purchase lower priced prescription drugs from our online service without a prescription and enjoy the convenience of online service and peace of mind when ordering from our secure online shopping system.
    Our team of dedicated professionals strive to make your online experience as quick and pleasant as possible. We pride ourselves in our ability to provide these services at a significantly lower cost than what one would normally pay. All while avoiding any hidden charges or fees.

    Pills and chemicals Online

    Pain killers


    anxiety pills for sale


    Adderall for sale

    nandrolone decanoate for sale

    Winstrol stanozolol for sale online

    Buy trenbolone acetate online

    stanozolol depot online

    Buy testosterone mix online

    Buy sustanon online

    Buy primobolan acetate online

    Buy testosterone enanthate online

    Buy Dianabol online

    Buy turinabol with Bitcoin online

    british dragon eu primo for sale

    British dragon eu online

  8. Really, helpful blog on human pheromones. Thanks for sharing.

  9. Legit Online Drug Supplier Welcome legit online drugstore buy all your pills here, cocaine for sale online, buy ecstasy, amphetamine pills, crack, cocaine.

    Link: Buy Cocaine online

    Link: Buy Pure Grade Heroin online

    Link: Buy Fentanyl online

    Link: Buy GHB Powder online

    Link: Buy Amphetamine Powder online

    Link: Buy Marijuana online

    Link: Buy Tapentadol Tablets online

    Link: Cocaine Wholesale online

  10. Really appreciate this wonderful post that you have provided for us.Great site and a great topic as well i really get amazed to read this. Its really good. dianabol cycle