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By MARY LOU JEPSEN IN my early 30s, for a few months, I altered my body chemistry and hormones so that I was closer to a man in his early 20s. I was blown away by how dramatically my thoughts changed. I was angry almost all the time, thought about sex constantly, and assumed I was the smartest person in the entire world. Over the years I had met guys rather like this. I was not experimenting with hormone levels out of idle curiosity or in some kind of quirky science experiment. I was on hormone treatments because I’d had a tumor removed along with part of my pituitary gland, which makes key hormones the body needs to function. This long journey may have started as early as 1978, when I was 13. I spent a summer in intensive care with an unknown disease. After that summer, I never thought I would live a long life. So I wanted to live, to do interesting, fascinating work in the limited time I thought I had left. I took on the math-intensive art form of holography, and in my early 20s traveled the world, living on university fellowships to pursue this esoteric craft. I didn’t date much, really — perhaps because I didn’t have many hormones, though I didn’t know that at the time. I worked as an artist, played in a band, met Andy Warhol, Christo, Lou Reed and David Byrne. I had fun. But the gravity of my illness grew in the 1990s. The growth that shut down my pituitary gland’s ability to produce hormones did so insidiously over many years. By my early 20s it was, I suspect in retrospect, causing misdiagnosis of symptoms that were most likely caused by lack of hormones like cortisol. No diagnosis was found, despite the efforts of many doctors. I was a doctoral student in electrical engineering at an Ivy League school, but was growing progressively worse. I routinely slept about 20 hours a day, lived with a constant blistering headache and frequent vomiting, and was periodically wheelchair-bound. Large sections of my skin cycled through a rainbow of colors and sores, half of my face wouldn’t move as if Novocain had been applied. I drooled. Worse: I felt stupid. I couldn’t subtract anymore. I couldn’t make a to-do list, let alone accomplish items on one. I recognized that I wasn’t capable of continuing in graduate school. Utterly defeated, I filled out the paperwork to drop out. © 2013 The New York Times Company

Related chapters from BP7e: Chapter 5: Hormones and the Brain; Chapter 15: Emotions, Aggression, and Stress
Related chapters from MM:Chapter 8: Hormones and Sex; Chapter 11: Emotions, Aggression, and Stress
Link ID: 18969 - Posted: 11.25.2013

By NATASHA SINGER One afternoon a few months ago, a 45-year-old sales representative named Mike called “The Dr. Harry Fisch Show,” a weekly men’s health program on the Howard Stern channel on Sirius XM Radio, where no male medical or sexual issue goes unexplored. “I feel like a 70-year-old man in a 45-year-old body,” Mike, from Vancouver, British Columbia, told Dr. Fisch on the live broadcast. “I want to feel good. I don’t want to feel tired all day.” A regular listener, Mike had heard Dr. Fisch, a Park Avenue urologist and fertility specialist, talk about a phenomenon called “low testosterone” or “low T.” Dr. Fisch likes to say that a man’s testosterone level is “the dipstick” of his health; he regularly appears on programs like “CBS This Morning” to talk about the malaise that may coincide with low testosterone. He is also the medical expert featured on IsItLowT.com, an informational website sponsored by AbbVie, the drug maker behind AndroGel, the best-selling prescription testosterone gel. Like many men who have seen that site or commercials or online quizzes about “low T,” Mike suspected that diminished testosterone was the cause of his lethargy. And he hoped, as the marketing campaigns seem to suggest, that taking a prescription testosterone drug would make him feel more energetic. “I took your advice and I went and got my testosterone checked,” Mike told Dr. Fisch. Mike’s own physician, he related, told him that his testosterone “was a little low” and prescribed a testosterone medication. Mike also said he had diabetes and high blood pressure and was 40 pounds overweight. Dr. Fisch explained that conditions like obesity might be accompanied by decreased testosterone and energy, and he urged Mike to exercise more and to lose weight. But if Mike had trouble overhauling his diet and exercise habits, Dr. Fisch said, taking testosterone might give him the boost he needed to do so. “If it gives you more energy to exercise,” Dr. Fisch said of the testosterone drug, “I’m all for it.” © 2013 The New York Times Company

Related chapters from BP7e: Chapter 12: Sex: Evolutionary, Hormonal, and Neural Bases; Chapter 5: Hormones and the Brain
Related chapters from MM:Chapter 8: Hormones and Sex; Chapter 8: Hormones and Sex
Link ID: 18968 - Posted: 11.25.2013

By Rahul K. Parikh, The message showed up on my desk one day while I was seeing a patient. Its choppy shorthand read: “Admits to injecting testosterone. Now decreased libido. Call back to discuss.” The caller was a 15-year-old lacrosse player who hadn’t been part of my practice long. Like many boys in his age group, he rarely came to the office. When I responded to his message later that afternoon, the young man carried his end of the conversation with the typical terseness of a teenager. “Where did you get the steroids?” I asked. “On the Internet.” “How long did you use them?” “A few months.” “And what are you experiencing now?” He told me his nipples were sore and swollen. “I’ve been more tired and moody as well.” My patient was experiencing classic side effects of steroid use. About 6 percent of teenagers admit to using performance-enhancing drugs, according to a recent survey, though it’s easy to assume that that number is low. How many teens would admit to using such drugs, even anonymously to a researcher? And yet here was one teen, forced by the drug’s side effect, having to make an embarrassing confession to me and his family. (Details of this case have been altered to protect patient privacy.) Despite my patient’s fear, I was confident that a young, healthy teenager who briefly used steroids would bounce back, though it might take some time — and patience — for his symptoms to dissipate. When I explained this to my patient, he told me that he wanted his testosterone level tested, to make sure there wasn’t something more seriously wrong. I got the sense that he thought there was some way I could magically undo the harm he had caused himself. I paused and considered his request, which came across more like an order. © 1996-2013 The Washington Post

Related chapters from BP7e: Chapter 12: Sex: Evolutionary, Hormonal, and Neural Bases; Chapter 5: Hormones and the Brain
Related chapters from MM:Chapter 8: Hormones and Sex; Chapter 8: Hormones and Sex
Link ID: 18947 - Posted: 11.20.2013

By ELISABETH ROSENTHAL The barrage of advertisements targets older men. “Have you noticed a recent deterioration of your ability to play sports?” “Do you have a decrease in sex drive?” “Do you have a lack of energy?” If so, the ads warn, you should “talk to your doctor about whether you have low testosterone” — “Low T,” as they put it. In the view of many physicians, that is in large part an invented condition. Last year, drug makers in the United States spent $3.47 billion on advertising directly to consumers, according to FiercePharma.com. And while ever-present ads like those from AbbVie Pharmaceuticals have buoyed sales of testosterone gels, that may be bad for patients as well as the United States’ $2.7 trillion annual health care bill, experts say. Sales of prescription testosterone gels that are absorbed through the skin generated over $2 billion in American sales last year, a number that is expected to more than double by 2017. Abbott Laboratories — which owned AbbVie until Jan. 1 — spent $80 million advertising its version, AndroGel, last year. Once a niche treatment for people suffering from hormonal deficiencies caused by medical problems like endocrine tumors or the disruptive effects of chemotherapy, the prescription gels are increasingly being sold as lifestyle products, to raise dipping levels of the male sex hormone as men age. “The market for testosterone gels evolved because there is an appetite among men and because there is advertising,” said Dr. Joel Finkelstein, an associate professor at Harvard Medical School who is studying male hormone changes with aging. “The problem is that no one has proved that it works and we don’t know the risks.” © 2013 The New York Times Company

Related chapters from BP7e: Chapter 5: Hormones and the Brain; Chapter 12: Sex: Evolutionary, Hormonal, and Neural Bases
Related chapters from MM:Chapter 8: Hormones and Sex; Chapter 8: Hormones and Sex
Link ID: 18790 - Posted: 10.16.2013

By DENISE GRADY Hormone therapy for menopause is one of the most divisive subjects in medicine, hailed by some as a boon to women’s comfort and well-being, vilified by others as a threat to health. A new analysis finds truth somewhere in the middle, reaffirming previous warnings that the drugs have more risks than benefits for most women — but also stating that the harms are low early in menopause and that hormones are “appropriate for symptom management in some women.” Dr. JoAnn E. Manson, the first author of the analysis and a professor of medicine at Harvard’s medical school, said in an interview that the findings “should not be used as a basis for denying women treatment if they’re in early menopause and have significant distressing symptoms.” The new report, published on Tuesday in The Journal of the American Medical Association, is based on long-term data from the Women’s Health Initiative, a large, federally funded study that turned medical thinking on its head a decade ago by uncovering the risks of hormones. The new report is the first to include extended follow-up data from the original health initiative study, an additional six to eight years’ worth of information on about 80 percent of the original participants. They took a combination of estrogen and progesterone, estrogen alone or placebos for several years. For combined hormones, for every 10,000 women taking the drugs, the new analysis found that there were six additional instances of heart problems, nine more strokes, nine more blood clots in the lungs and nine more cases of breast cancer. On the benefit side, there were six fewer cases of colorectal cancer, one fewer case of uterine cancer, six fewer hip fractures and one fewer death. Most of the effects wore off once the drugs were stopped, but the risk of breast cancer remained slightly elevated. © 2013 The New York Times Company

Related chapters from BP7e: Chapter 5: Hormones and the Brain
Related chapters from MM:Chapter 8: Hormones and Sex
Link ID: 18733 - Posted: 10.02.2013

Mark Peplow Hormone-disrupting chemicals may be far more prevalent in lakes and rivers than previously thought. Environmental scientists have discovered that although these compounds are often broken down by sunlight, they can regenerate at night, returning to life like zombies. “The assumption is that if it’s gone, we don’t have to worry about it,” says environmental engineer Edward Kolodziej of the University of Nevada in Reno, joint leader of the study. “But we’re under-predicting their environmental persistence.” “Risk assessments have been built on the basis that light exposure is enough to break down these products,” adds Laura Vandenberg, an endocrinologist at the University of Massachusetts in Amherst who was not involved in the study. “This work undermines that idea completely.” Endocrine disruptors — pollutants that unbalance hormone systems — are known to harm fish, and there is growing evidence linking them to health problems in humans, including infertility and various cancers1. But pinpointing specific culprits from the vast array of trace chemicals in the environment has proved difficult. Indeed, concentrations of known endocrine disruptors in rivers often seem to be too low to explain harmful effects in aquatic wildlife, says Kolodziej. He and his colleague David Cwiertny, an environmental engineer at the University of Iowa in Iowa City, decided to find out whether the breakdown products of endocrine disruptors could be boosting their environmental impact. Their team focused on trenbolone acetate, a synthetic anabolic steroid used as a growth promoter in more than 20 million cattle in the United States each year (this practice is banned in the European Union). © 2013 Nature Publishing Group

Related chapters from BP7e: Chapter 12: Sex: Evolutionary, Hormonal, and Neural Bases; Chapter 5: Hormones and the Brain
Related chapters from MM:Chapter 8: Hormones and Sex; Chapter 8: Hormones and Sex
Link ID: 18711 - Posted: 09.28.2013

Oxytocin, the naturally occuring human hormone linked to bonding with a newborn and romantic partner, could also help improve mood after rejection, a laboratory study suggests. When scientists in Montreal gave 100 students either oxytocin or a placebo through a nose spray and then tried to snub them in a conversation, feelings of trust were higher in the hormone group. But the hormone had no effect among those who weren't emotionally charged up by the social rejection of having researchers posing as students disagree, interrupt or ignore them. "Instead of the traditional 'fight or flight' response to social conflict where people get revved up to respond to a challenge or run away from it, oxytocin may promote the 'tend and befriend' response where people reach out to others for support after a stressful event. That can, in turn, strengthen social bonds and may be a healthier way to cope," study author Mark Ellenbogen said in a release. For a decade, researchers have speculated that oxytocin, known as the love hormone, motivates people to seek out social support to respond to challenges and blunt the negative hit of stress. Ellenbogen's team said its study offers the first experimental support of the idea that oxytocin motivates us to strengthen social bonds during times of distress. © CBC 2013

Related chapters from BP7e: Chapter 12: Sex: Evolutionary, Hormonal, and Neural Bases; Chapter 8: General Principles of Sensory Processing, Touch, and Pain
Related chapters from MM:Chapter 8: Hormones and Sex; Chapter 5: The Sensorimotor System
Link ID: 18351 - Posted: 07.06.2013

A randomized clinical trial of estrogen therapy in younger postmenopausal women, aged 50–55, has found no long-term risk or benefit to cognitive function. The National Institutes of Health-supported study, reported in JAMA Internal Medicine on June 24, 2013, looked at women taking conjugated equine estrogens, the most common type of postmenopausal hormone therapy in the United States. The earlier Women’s Health Initiative Memory Study (WHIMS) linked the same type of hormone therapy to cognitive decline and dementia in older postmenopausal women. The new findings come from the Women’s Health Initiative Memory Study of Younger Women (WHIMSY) trial and were reported by Mark A. Espeland, Ph.D., Wake Forest School of Medicine, Winston-Salem, N.C., on behalf of the academic research centers involved in the study. The study was funded primarily by the National Institute on Aging (NIA), along with the National Heart, Lung, and Blood Institute (NHLBI), both components of the NIH. “The WHIMS study found that estrogen-based postmenopausal hormone therapy produced deficits in cognitive function and increased risk for dementia when prescribed to women 65 and older,” said NIA Director Richard J. Hodes, M.D. “Researchers leading the WHIMSY study wanted to expand on those results by exploring the possibility of a window of opportunity whereby hormone therapy might promote or preserve brain health when given to younger women.” “In contrast to findings in older postmenopausal women, this study tells women that taking these types of estrogen-based hormone therapies for a relatively short period of time in their early postmenopausal years may not put them at increased risk for cognitive decline over the long term,” said Susan Resnick, Ph.D., chief of the Laboratory of Behavioral Neuroscience, in NIA’s Intramural Research Program and a co-author of the study. “Further, it is important to note that we did not find any cognitive benefit after long-term follow-up.”

Related chapters from BP7e: Chapter 5: Hormones and the Brain; Chapter 12: Sex: Evolutionary, Hormonal, and Neural Bases
Related chapters from MM:Chapter 8: Hormones and Sex; Chapter 8: Hormones and Sex
Link ID: 18310 - Posted: 06.25.2013

By ANAHAD O'CONNOR The number of middle-aged men with prescriptions for testosterone is climbing rapidly, raising concerns that increasing numbers of men are abusing the powerful hormone to boost their libidos and feel younger, researchers reported on Monday. Testosterone replacement therapy is approved specifically for the treatment of abnormally low testosterone levels, a condition called hypogonadism. The hormone helps build muscle, reduce body fat and improve sex drive. But a study published in the journal JAMA Internal Medicine found that many men who get prescriptions for the hormone have no evidence of a deficiency at all. The new study is the largest of testosterone prescribing patterns to date, involving nearly 11 million men who were tracked through a large health insurer. The report showed that the number of older and middle-aged men prescribed the hormone has tripled since 2001. Men in their 40s represent the fastest-growing group of users. About half of men prescribed testosterone had a diagnosis of hypogonadism, and roughly 40 percent had erectile or sexual dysfunction. One third had a diagnosis of fatigue. The medical group that sets clinical guidelines for testosterone replacement therapy, the Endocrine Society, recommends treatment only in men who have unequivocally low testosterone levels. That finding requires a blood test. But the new report found that a quarter of men did not have their levels tested before they received the hormone. It was also unclear what proportion of men who did undergo testing actually had results showing a deficiency. Copyright 2013 The New York Times Company

Related chapters from BP7e: Chapter 5: Hormones and the Brain; Chapter 12: Sex: Evolutionary, Hormonal, and Neural Bases
Related chapters from MM:Chapter 8: Hormones and Sex; Chapter 8: Hormones and Sex
Link ID: 18228 - Posted: 06.04.2013

Jo Marchant People with genes that make it tough for them to engage socially with others seem to be better than average at hypnotizing themselves. A study published today in Psychoneuroendocrinology1 concludes that such individuals are particularly good at becoming absorbed in their own internal world, and might also be more susceptible to other distortions of reality. Psychologist Richard Bryant of the University of New South Wales in Sydney and his colleagues tested the hypnotizability of volunteers with different forms of the receptor for oxytocin, a hormone that increases trust and social bonding. (Oxytocin's association with emotional attachment also earned it the nickname of 'love hormone'.) Those with gene variants linked to social detachment and autism were found to be most susceptible to hypnosis. Hypnosis has intrigued scientists since the nineteenth-century physician James Braid used it to alleviate pain in a variety of medical conditions, but it has never been fully understood. Hypnotized people can undergo a range of unusual experiences, including amnesia, anaesthesia and the loss of the ability to move their limbs. But some individuals are more affected by hypnosis than others — and no one knows why. Hormones and hypnotism How susceptible someone is to persuasion is an important factor in how easily they can be hypnotized by someone else. Bryant and his colleagues have previously shown that spraying a shot of oxytocin up people’s noses makes them more hypnotizable, and more likely to engage in potentially embarrassing activities such as swearing or dancing at a hypnotist’s suggestion. © 2013 Nature Publishing Group,

Related chapters from BP7e: Chapter 5: Hormones and the Brain; Chapter 18: Attention and Higher Cognition
Related chapters from MM:Chapter 8: Hormones and Sex; Chapter 14: Attention and Consciousness
Link ID: 18052 - Posted: 04.20.2013

By Kate Clancy I tend to go to bed freezing, especially so in the winter, so I pile our flannel sheet, blanket, and down comforter over me when I settle in to sleep. A few times each menstrual cycle, clustered together in the luteal phase between ovulation and menses, I wake up from sleep completely soaked in my own sweat – not a delightful sight or experience. Usually I get up, change pajamas, and try to find a dry spot on the bed to go back to sleep (I promise the sheets eventually get washed, but I’m not about to wake my husband – and sometimes daughter – to change the bed at 3am). These night sweats started when I was still intensively breastfeeding my daughter and was marathon training, when she was under a year old. At first, I thought it was because we were co-sleeping and we slept next to each other. But I never experienced them next to my husband before that point, and he is a six foot four heat generating machine. When the marathon was over and I returned to less strenuous activity, breastfeeding frequency was also starting to decline. I didn’t get any night sweats again for quite some time. Then there was roller derby. At first, roller derby was a pastime, a recreational activity where I got to learn something totally new and hang out with women I respected. But of course, being the competitive person I am, it became an obsession, and in addition to roller derby practices I was working out quite a lot on my own time. Over the last year I’ve made additional nutritional adjustments to further improve my performance, and I’ve increased the intensity of my off-skates workouts. I work out a minimum of five hours a week, but in the middle of the season it is usually a minimum of nine hours per week. © 2012 Scientific American

Related chapters from BP7e: Chapter 5: Hormones and the Brain; Chapter 13: Homeostasis: Active Regulation of the Internal Environment
Related chapters from MM:Chapter 8: Hormones and Sex; Chapter 9: Homeostasis: Active Regulation of the Internal Environment
Link ID: 17609 - Posted: 12.17.2012

By GRETCHEN REYNOLDS Is playing football like falling in love? That question, which would perhaps not occur to most of us watching hours of the bruising game this holiday season, is the focus of a provocative and growing body of new science examining the role of oxytocin in competitive sports. Oxytocin is, famously, the “love hormone,” a brain peptide known to promote positive intersocial relations. It makes people like one another, especially in intimate relationships. New mothers are awash in oxytocin (which is involved in the labor process), and it is believed that the hormone promotes bonding between mother and infant. New-formed romantic couples also have augmented bloodstream levels of the peptide, many studies show. The original attraction between the lovers seems to prompt the release of oxytocin, and, in turn, its actions in the brain intensify and solidify the allure. Until recently, though, scientists had not considered whether a substance that promotes cuddliness and warm, intimate bonding might also play a role in competitive sports. But the idea makes sense, says Gert-Jan Pepping, a researcher at the Center for Human Movement Sciences at the University of Groningen in The Netherlands, and the author of a new review of oxytocin and competition. “Being part of a team involves emotions, as for instance when a team scores, and these emotions are associated with brain chemicals.” Copyright 2012 The New York Times Company

Related chapters from BP7e: Chapter 5: Hormones and the Brain; Chapter 15: Emotions, Aggression, and Stress
Related chapters from MM:Chapter 8: Hormones and Sex; Chapter 11: Emotions, Aggression, and Stress
Link ID: 17517 - Posted: 11.21.2012

By Melissa Healy, Los Angeles Times If retired Army Gen. David H. Petraeus had gotten an occasional dose of supplemental oxytocin, a brain chemical known to promote trust and bonding, he might still be director of the Central Intelligence Agency, new research suggests. A study published Tuesday in the Journal of Neuroscience has uncovered a surprising new property of oxytocin, finding that when men in monogamous relationships got a sniff of the stuff, they subsequently put a little extra space between themselves and an attractive woman they'd just met. Oxytocin didn't have the same effect on single heterosexual men, who comfortably parked themselves between 21 and 24 inches from the comely female stranger. The men who declared themselves in "stable, monogamous" relationships and got a dose of the hormone chose to stand, on average, about 6 1/2 inches farther away. When researchers conducted the experiment with a placebo, they found no differences in the distance that attached and unattached men maintained from a woman they had just met. Even when an attractive woman was portrayed only in a photograph, the monogamous men who received oxytocin put a bit more distance between themselves and her likeness. But when the new acquaintance was a man, administration of oxytocin did not prompt attached men to stand farther away than single men, the researchers reported. Los Angeles Times, Copyright 2012

Related chapters from BP7e: Chapter 5: Hormones and the Brain; Chapter 12: Sex: Evolutionary, Hormonal, and Neural Bases
Related chapters from MM:Chapter 8: Hormones and Sex; Chapter 8: Hormones and Sex
Link ID: 17495 - Posted: 11.17.2012

by Andy Coghlan Men with partners increase the space they feel comfortable with between themselves and an attractive woman if exposed to the bonding hormone oxytocin. René Hurlemann at the University of Bonn in Germany and colleagues gave men either a sniff of oxytocin or a placebo before asking them to choose the ideal distance for an interaction with a woman. The distance that they felt was comfortable significantly increased after sniffing oxytocin, but only for men in relationships. The team conclude that oxytocin discourages partnered but not single men from getting close to a female stranger. Journal reference: Journal of Neuroscience, DOI: 10.1523/jneurosci.2755-12.2012 © Copyright Reed Business Information Ltd.

Related chapters from BP7e: Chapter 5: Hormones and the Brain; Chapter 12: Sex: Evolutionary, Hormonal, and Neural Bases
Related chapters from MM:Chapter 8: Hormones and Sex; Chapter 8: Hormones and Sex
Link ID: 17489 - Posted: 11.14.2012

By Gary Stix First off, this study on a molecule tied to social interaction was conducted in animals. So I’m supposed to turn on the siren and the flashing red light here to let you know that the headline you just read might not apply in humans. Still, the animals in question, prairie voles, are a special case, models of faithfulness that put humans to shame when it comes to the delicate topic of monogamy. Once hitched, the rodents stick with their mates for life—an example of moral pulchritude in the animal kingdom that many of us human sinners can never hope to emulate. It could easily become the state animal for whole regions of the U.S. For just that alone, the implications of the experiment in question are particularly intriguing. The new research shows that oxytocin, the bonding hormone, is sometimes capable of turning the upstanding rodent into an anti-social lout, making the study results more compelling in many ways than if they were reported in errant humans. So the man-bites-dog headline stays. This all came up when Karen Bales, a professor at University of California, Davis, wanted to know what would happen if oxytocin gets administered for lengthy intervals, not the short-term dosing that has occurred in the multitude of previous vole studies that linked the hormone to monogamous behavior. In their experiment, Bales and team gave either a low, medium or high dose through the nose to 29 voles, and a saline solution to 14 controls At first, the animals became all cuddly as in previous studies But after three weeks, an entire vole childhood (from weaning to sexual maturity), they started breaking bad. Males did not engage in the normal behavior of “pair bonding,” that drives them to look for the girl of their dreams. And female voles’ natural mothering instinct seemed to disappear: when placed nearby young pups that were not their own, they didn’t dote, as they are wont to do. The cuddle hormone had turned the rodents into meanies. © 2012 Scientific American

Related chapters from BP7e: Chapter 12: Sex: Evolutionary, Hormonal, and Neural Bases; Chapter 5: Hormones and the Brain
Related chapters from MM:Chapter 8: Hormones and Sex; Chapter 8: Hormones and Sex
Link ID: 17379 - Posted: 10.17.2012

(Relaxnews)—In a study of more than 90 men, scientists from the University of Bonn, Germany, found that subjects treated with a dose of testosterone before the study told fewer lies than those who received a placebo. "Testosterone has always been said to promote aggressive and risky behavior and posturing," says researcher and neuroscientist Bernard Weber. However, more recent studies indicate that it also fosters social behavior. Prior research has suggested that the hormone may actually cause people to be more "prosocial" in that they voluntarily act in the interest of others, writes the Atlantic magazine, but exactly how the hormone influences behaviors isn't understood. For this latest study, 46 subjects were treated with testosterone by applying it to the skin in gel form, while 45 subjects received a placebo. The next day, the subjects played a dice game in which it was easy for the men to lie to earn more money, with no possibility of being caught. The study was designed so that it was impossible even for the researchers to detect whether a subject was lying or not. Rather, they used statistics to analyze reported earnings that were higher than probability would allow, inferring from these how honest the subjects were being. While many people in the study lied about the game, there was a noticeable difference between the men boosted with testosterone and those who weren't—the testosterone group avoided the temptation to cheat more often. Blood tests confirmed the results that high testosterone levels were linked with more honest game playing. "Test subjects with the higher testosterone levels had clearly lied less frequently than untreated test subjects," says co-author Armin Falk. "This result clearly contradicts the one-dimensional approach that testosterone results in anti-social behavior." The study was published last week in the journal PLoS One . http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0046774 © 2012 NY Times Co.

Related chapters from BP7e: Chapter 5: Hormones and the Brain; Chapter 12: Sex: Evolutionary, Hormonal, and Neural Bases
Related chapters from MM:Chapter 8: Hormones and Sex; Chapter 8: Hormones and Sex
Link ID: 17378 - Posted: 10.17.2012

by Gisela Telis In the industrialized world, women live at least 5 years longer, on average, than men. Scientists have attributed that difference to everything from healthier habits to hardier cells. Now, a new study that analyzes the longevity of eunuchs, or castrated men, suggests that testosterone may play a part in shortening men's lives. The idea that testosterone, the male sex hormone, affects lifespan isn't new. Neutered dogs and other animals that have had their sources of testosterone removed often live longer than their intact counterparts. But studies on the connection between castration and longevity in humans are harder to come by, and the results have been inconclusive. A 1969 study of institutionalized patients in Kansas found that castrated men lived an average of 14 years longer than other men in the same facility, but a 1993 study of Italian castrati (singers castrated as boys to preserve their high voices) found nothing unusual about their longevity. Almost 5 years ago, biologist Kyung-Jin Min of Inha University in Incheon, Korea, found himself considering this lack of data while watching a Korean TV drama about eunuchs. Min began to wonder if Korea's rich historical records could shed light on the link between castration and longevity in humans. Until the late 19th century, Korean rulers employed eunuchs to serve the royal court. These eunuchs were allowed to marry and adopt castrated boys as their sons. The Yang-Se-Gye-Bo, a genealogical record of the eunuch families, has survived, and it documents the birth and death dates and other personal details of 385 eunuchs who lived between the mid-16th century and the mid-19th century. © 2010 American Association for the Advancement of Science.

Related chapters from BP7e: Chapter 5: Hormones and the Brain; Chapter 12: Sex: Evolutionary, Hormonal, and Neural Bases
Related chapters from MM:Chapter 8: Hormones and Sex; Chapter 8: Hormones and Sex
Link ID: 17298 - Posted: 09.25.2012

By Judy Stone In one sense, it is refreshing to see men being the target of pharma, after all these years of women being the focus of relentless—and misleading—advertising. On the other, we’re seeing the start of yet another pharma campaign to dupe the public by the unnecessary medicalization of symptoms to create new drug markets. I used to be a fairly enthusiastic pharma fan, but over recent years have become increasingly disillusioned. The hype over testosterone is the latest example of why. With so many pressing problems in the world, I wish pharma would focus their attention on doing something more useful with their energies. I thought it started with drugs for “hot flashes,” but Karen Roush set me straight about hormone therapy, reporting that “It all started with men in ancient civilizations eating the penis and testicles of animals as a cure for impotence.” (And to think that Maryn McKenna just warned us of the dangers of kissing cats! This early hormone therapy sounds a bit dicier.) In the 1940s, estrogen was able to be extracted from horse urine in large quantities, enabling a supply for treating women “suffering from estrogen deficiency.” Dr. Robert Wilson, a prominent New York gynecologist, founded a private trust in 1963 to promote estrogen use. Pharmaceutical companies provided $1.3 million to this “trust;” they, of course, stood to profit handsomely from their investment in Wilson’s endeavor. Wilson is described as being “evangelical” in his crusade to save women from the “decay” of menopause. He was quite successful, with his 1966 book, Feminine Forever, selling 100,000 copies in the first seven months alone. His theme, “A Plea for the Maintenance of Adequate Estrogen from Puberty to Grave,” expounded in a mainstream medical journal, was adopted both by the medical profession and by the popular press. © 2012 Scientific American

Related chapters from BP7e: Chapter 5: Hormones and the Brain; Chapter 12: Sex: Evolutionary, Hormonal, and Neural Bases
Related chapters from MM:Chapter 8: Hormones and Sex; Chapter 8: Hormones and Sex
Link ID: 17258 - Posted: 09.15.2012

By GRETCHEN REYNOLDS It’s widely accepted among scientists that regular exercise transforms the brain, improving the ability to remember and think. And a growing and very appealing body of science has established that exercise spurs the creation of new brain cells, a process known as neurogenesis. But just how jogging or other workouts affect the structure of the brain has remained enigmatic, with many steps in the process unexplained. A new study published last month in Proceedings of the National Academy of Sciences may fill in one piece of the puzzle, by showing that male sex hormones surge in the brain after exercise and could be helping to remodel the mind. The research was conducted on young, healthy and exclusively male rats – but scientists believe it applies to female rats, too, as well as other mammals, including humans. The decision to use only males was carefully considered. “We’ve known for a while that estrogen,” the female sex hormone, “is produced in the brain” not just of female animals but also, to some degree, in males, says Bruce S. McEwen, the director of the Laboratory of Neuroendocrinology at Rockefeller University in New York and an author of the study, which also involved scientists from the University of Tsukuba in Japan and other institutions. Estrogen has been well studied and has many effects, he said, including, scientists suspect, new brain cell growth. But far less has been known about the role of male sex hormones in mammalian brains, particularly after exercise. While both sexes produce male sex hormones, males produce far more of it – mostly in the gonads but, the researchers suspected, also in the brain. Copyright 2012 The New York Times Company

Related chapters from BP7e: Chapter 5: Hormones and the Brain; Chapter 12: Sex: Evolutionary, Hormonal, and Neural Bases
Related chapters from MM:Chapter 8: Hormones and Sex; Chapter 8: Hormones and Sex
Link ID: 17250 - Posted: 09.13.2012

By Matthew Perrone, Associated Press "Do you have a decrease in libido?" "Have you noticed a recent deterioration in your ability to play sports?" "It could be Low-T." Welcome to the latest big marketing push by the nation's drug companies. In this case, it's a web page for Abbott Laboratories' Androgel, a billion-dollar selling testosterone gel used by millions of American men struggling with the symptoms of growing older that are associated with low testosterone, such as poor sex drive, weight gain and fatigue. Androgel is one of a growing number of prescription gels, patches and injections aimed at boosting the male hormone that begins to decline after about age 40. Drugmakers and some doctors claim testosterone therapy can reverse some of the signs of aging — even though the safety and effectiveness of such treatments is unclear. "The problem is that we don't have any evidence that prescribing testosterone to older men with relatively low testosterone levels does any good," says Dr. Sergei Romashkan, who oversees clinical trials for the National Institute on Aging, a part of the National Institutes of Health conglomerate of research centers. Low testosterone is the latest example of a once-natural part of getting old that has become a target for medical treatment. Bladder problems, brittle bones and hot flashes have followed a similar path: from inconvenient facts of life, to ailments that can be treated with drugs. The rise of such therapies is being fueled by both demographics and industry marketing. © 2012 NBCNews.com

Related chapters from BP7e: Chapter 5: Hormones and the Brain; Chapter 12: Sex: Evolutionary, Hormonal, and Neural Bases
Related chapters from MM:Chapter 8: Hormones and Sex; Chapter 8: Hormones and Sex
Link ID: 17236 - Posted: 09.10.2012