Men’s Health

Serious But Rare Genetic Immune Disorder Studied By Scientists

admin — Sun, 20 May 2012 01:19:49 +0000

Defects in the gene that encodes the XIAP protein result in a serious immune malfunction. Scientists used biochemical analyses to map the protein’s ability to activate vital components of the immune system. Their results have recently been published in
Molecular Cell,
a journal of international scientific repute.
Researchers at The Novo Nordisk Foundation Center for Protein Research at the University of Copenhagen have mapped how the XIAP protein activates a vital component of the immune defence system, specifically the component that fights bacterial infections in the gastro-intestinal system:
“Our results are an important step on the way to understanding the very serious – but fortunately rare – genetic immune disorder called X-linked lymphoproliferative syndrome type 2 (XLP2), which affects male children,” says Associate Professor Mads Gyrd-Hansen from the The Novo Nordisk Foundation Center for Protein Research, and explains more about the disease:
“The gastro-intestinal system can be viewed as a long tube running through the body, absorbing nutrients and water. The contact surface between the intestinal system and the rest of the body is protected by an efficient immune barrier that confines the bacteria to the intestine. This barrier is not intact in XLP2 patients, who thus lack the necessary bulwark, so to say, between bacteria and body.”
shows that genetic mutations found in patients with XLP2 specifically destroy XIAP’s ability to attach the signalling protein ubiquitin to other proteins. The attachment process is vital for activating the immune system and therefore for survival.
are first and foremost relevant for XLP2 patients,
“Several pharmaceutical companies have developed drugs to act on IAP proteins, including XIAP, as part of cancer treatment. Several of the drugs are currently being tested in clinical trials for their efficacy in treatment of
and other forms of cancer. It is therefore essential to know precisely which biological processes in the organism the treatment can potentially affect,” continues Mads Gyrd-Hansen.
Mads Gyrd-Hansen and his colleagues at The Novo Nordisk Foundation Center for Protein Research have been collaborating for a good 18 months together with research groups in Germany, the UK and Australia, and the competencies of the individual groups have made it possible to rapidly achieve high-quality results quickly:
“International collaboration has made it possible – in a short time – to describe detailed molecular processes, to use the descriptions to create mouse models for further tests and thereafter to link the results of these tests to genetic mutations identified in patients.”

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The Risks Of Running Marathons

admin — Thu, 17 May 2012 06:58:57 +0000

Even though hundreds of thousands more people finished grueling 26.2 mile marathons in the United States in 2009 compared to a decade earlier, a runner’s risk of dying during or soon after the race has remained very low – about .75 per 100,000, new Johns Hopkins research suggests. Men, however, were twice as likely to die as women.
“It’s very dramatic when someone dies on the course, but it’s not common,” says Julius Cuong Pham, M.D., Ph.D., an associate professor of emergency medicine and anesthesiology and critical care medicine at the Johns Hopkins University School of Medicine, and leader of the study published online in The American Journal of Sports Medicine. “There are clearly many health benefits associated with running. It doesn’t make you immune, but your risk of dying from running a marathon is very, very low.”
Pham and his colleagues found that between 2000 and 2009, 28 people died during or in the 24 hours following, a marathon, most of them men. Half of those who died were over age 45, and all but one in the over-45 group died of
. For younger runners, the cause of death varied widely and included cardiac
and hyponatremia, the latter owing to drinking excessive amounts of water.
Marathons have long been considered the pinnacle of endurance sports, but they have become wildly popular in recent years. Pham and colleagues looked at statistics from approximately 300 marathons per year and found that the number of finishers increased dramatically between 2000 and 2009, from 299,018 to 473,354. The researchers said they believe the recent increase in marathon popularity is partially because of increasing awareness of the health benefits gained from regular exercise.
, and to longevity, Pham says. Similarly, marathon running has been associated with decreased risks of
, high
. People who run regularly have been found to have lower rates of all-cause mortality and disability.
With so many more people participating, Pham says he expected to find that the pace of marathons would have slowed over time, but the average finishing time also stayed steady at roughly four hours and 35 minutes.
One limitation of the study, however, is that there is no easily available access to data on the number of people who drop out of the races without finishing, which may have artificially kept average finishing times higher.
Pham, a three-time marathoner himself, cautions that people should not think that marathon training or running is risk-free. He noted that studies have shown the yearly incidence of injury in people training for marathons to be as high as 90 percent, with the vast majority of injuries damaging the musculoskeletal system.

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New Insights Into Urinary Tract Health Of Adolescent Males Revealed By Bacteria Study

admin — Mon, 14 May 2012 13:19:30 +0000

The first study using cultivation independent sequencing of the microorganisms in the adolescent male urinary tract has revealed that the composition of microbial communities colonizing the penis in young men depends upon their circumcision status and patterns of sexual activity.
This study, published in the online journal
, is the first by Indiana University researchers working with a four-year, $7 million grant from the National Institutes of Health’s Human Microbiome Project. It is also the first to reveal that urogenital bacterial communities of young men are surprisingly stable and that some of these bacteria are similar to species that colonize and protect healthy young women from sexually transmitted infections.
The research contradicts the accepted wisdom that pre-sexual men did not have bacteria in their urinary tracts.
“Young men had bacteria that looked similar to those of young healthy women,” said David E. Nelson, Ph.D., an assistant professor of biology at Indiana University Bloomington and the principal investigator of the research. “We think that these bacteria may promote genitourinary health in men, just as they do in women. This contradicts previous dogma that only sexually transmitted pathogens colonize the male urethra.”
The findings open doors for additional research that will lead to a deeper understand of men’s health.
“This is the first real investigator of the normal microbiology of men before they begin sexual activity,” Dr. Nelson said. “There are parallels between normal bacteria in young men and those in young women that are known to be protective.”
This discovery was not possible before the mapping of the human genome and the development of powerful sequencing tools, said J. Dennis Fortenberry, M.D., M.S., principal investigator of the NIH grant and professor of pediatrics in the Division of Adolescent Medicine at the IU School of Medicine.
The investigators used the advanced sequencing techniques to evaluate bacteria on the head of the penis as well as in the urethra in 18 adolescents younger than 18 years, he said. The researchers will follow these adolescents, along with dozens of others, for several years to determine how the types and amounts of bacteria present in and on the penis changes over time.
This study reports that the types of bacteria found on the penis were different than what was found in the urethra, and the bacteria found in circumcised adolescents differed from the bacteria found in the uncircumcised adolescents. These differences may be important in understanding why circumcision helps prevent
and other sexually transmitted infections in men.
They also discovered changes in the bacteria after sexual activity began.
“We have some sense that some of the bacteria in the urethra are essential to keeping men healthy,” Dr. Fortenberry said. “This research and the new technology will open doors to explore what is good about the bacteria, what they do and how.”
“At this point in the research, we are asking ‘chicken and egg’ questions,” Dr. Nelson said. “What comes first, the loss of normal bacteria, making a person more susceptible to sexually transmitted infections or, do you get colonized with other bacteria for some reason and that puts a person more at risk of contracting an STI.”
This research, like other longitudinal studies, should shed light on the sequence of events that leads to STIs and other urinary tract diseases such as a common male condition called non-gonococcal urethritis, whose cause is unknown.
Drs. Fortenberry and Nelson said they decided that looking at the microbiome of a cohort of young, non-sexually active males was the only way to determine what bacteria was normal for men. Without that information, researchers can’t determine the difference between healthy and unhealthy bacteria and know how to treat disease.

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Early Elevated HIV Infection Risk In Some Step Study Participants Confirmed By Study

admin — Sun, 13 May 2012 13:31:25 +0000

A long-term follow-up analysis of participants in the Step Study, an international HIV-vaccine trial, has confirmed that certain subgroups of male study participants were at higher risk of becoming infected after receiving the experimental vaccine compared to those who received a placebo. The vaccine used in the study did not contain the
virus, but it did contain HIV genes which were delivered to cells using a vector that employed a type of cold virus known as adenovirus serotype 5 (Ad5).
Of the 1,836 men examined in this study, 172 became infected with HIV. Within 18 months of enrollment or one year after the last vaccination, men who had neutralizing antibodies to Ad5 or who were uncircumcised, or both, had a two- to four-fold increased risk of acquiring an HIV infection, according to findings published in the online edition issue of the
Journal of Infectious Disease.
However, the study also found that the risk level waned after about 18 months to be equal to that of volunteers who received a placebo.
Why this association occurred, what the biological mechanisms were and why the risk of infection lessened with time are unknown and require more study, according to Ann Duerr, M.D., a member of the Vaccine and Infectious Disease Division of Fred Hutchinson Cancer Research Center, who led the data analysis.
“There seems to be some kind of biologic phenomena that affects infection risk,” she said.
The current study indicated that self-reported risk behaviors, such as unprotected sex, did not differ significantly between the vaccine and placebo arms of the Step trial.
The research also confirmed there was no elevated risk of infection in vaccinated men who were circumcised and who were Ad 5 seronegative (men who had no neutralizing antibodies to the adenovirus vector used in the vaccine). An earlier interim analysis of the Step Study data, done after immunizations in the vaccine trial were halted in 2007, also detected this relationship between Ad5 sero-status and vaccine-associated HIV risk. Today, only men who are circumcised and Ad5 seronegative are eligible to receive experimental HIV vaccines that use the adenovirus serotype 5 as a biological delivery mechanism.
Duerr said scientists need a better understanding of what happened biologically to men who became infected, before those who are uncircumcised or seropositive for Ad 5 are enrolled in future vaccine trials in which the adenovirus serotype 5 vector is used.
Ad 5 is used as a vector because it elicits a strong immune response by CD8 T cells. These cytotoxic T lymphocytes are thought to be responsible for controlling HIV infection.
In the current study, researchers analyzed data from male Step Study participants who enrolled in a trial that provided follow-up for up to four years after they enrolled in the Step study, or until Dec. 31, 2009, whichever came first.
The Step Study enrolled 3,000 male and female volunteers in North and South America, the Caribbean and Australia between 2004 and 2007. Injections in the study were halted in September 2007 after researchers detected a lack of effectiveness by the vaccine to prevent HIV acquisition or reduce HIV viral load in infected participants, and a higher-than-expected number of HIV infections in certain subgroups of vaccinees.

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Load-Bearing Exercise By Males In Their Early 20s May Shield Them From Osteoporosis In Old Age

admin — Sun, 13 May 2012 12:38:48 +0000

Young men who play volleyball, basketball or other load-bearing sports for four hours a week or more increase bone mass and might gain protection from developing
later in life, according to a new study in the May issue of the Journal of Bone and Mineral Research.
The study, the largest scale investigation of its kind, discovered that young men who actively resisted the urge to adopt a “couch-potato” lifestyle in their late twenties seemed to gain the biggest bone benefit. “Men who increased their load-bearing activity from age 19 to 24 not only developed more bone, but also had larger bones compared to men who were sedentary during the same period,” said senior study author Mattias Lorentzon, M.D., Ph.D., of the University of Gothenburg, in Sweden.
Bigger bones with more mass are thought to offer a shield against osteoporosis, a disease that affects men and women alike, in which bones become porous and weak over time and start to
by age 50 or later. “Osteoporosis actually seems to get its start by age 25 when bones start to lose tissue. So this study sends an important message to young men,” Lorentzon said. “The more you move, the more bone you build.”
Sports that involve jumping or fast starts and stops and increase the load put on the body’s bones seemed most associated with the enhanced protection for men. Lorentzon and his colleagues found that basketball and volleyball seemed the best kinds of activities for building bone mass, followed by soccer and tennis. Such load-bearing sports seem to push the body to form new bone tissue. Activities that do not put an increased load on the bones, like swimming and bicycling did not seem associated with the building of bigger bones or more bone mass, even though they offer other health benefits.
Osteoporosis affects more than 200 million people worldwide yet many are unaware that they are at risk. The disease has been called the silent epidemic because bone loss occurs without symptoms and the disease often is first diagnosed after a fracture. Osteoporosis is more common in women, but men also develop it – usually after age 65.
Previous studies suggest that load-bearing physical activity might shield men and women from bone loss, which occurs as part of the aging process. But Lorentzon and his colleagues wondered if the link would hold true in a very large study that followed men over a five-year period. To find out, the researchers evaluated 833 men who were 18- to 20-years old at the start of the study. The researchers measured the participants’ bone mass and collected information about their exercise habits. Five years later the recruits came back to the lab to report activity levels and get bone scans again.
The researchers discovered that men who both started off with a high level of load-bearing exercise at the study’s start and those who stepped up the pace had a better chance at building bone than men who remained sedentary or those who slacked off during the five year period. They found that for every hour of increased physical activity during the five-year study, the men in this study gained bone mass.
The study found that recruits who participated in load-bearing sports for four hours a week or more showed an increase in hip bone density of 1.3 percent. At the same time, men who remained sedentary during the five year study lost about 2.1 percent of bone mass in the hip, a worrisome finding because thinning hip bones are more likely to break later in life. Hip fractures in men often lead to serious disability and complications, including life-threatening post-surgery infections and cardiovascular events.
This study was conducted in white men recruited mostly from the city of Gothenburg, Sweden. However, Lorentzon noted the findings likely apply to Caucasian men in the United States and in other countries, and additional research must be done to show that such load-bearing exercise can protect men in other ethnic groups and women.
“Such research is crucial to understanding how osteoporosis develops and more importantly how to prevent it,” said Keith Hruska, M.D., president of the American Society for Bone and Mineral Research (ASBMR), the world’s leading scientific organization for bone health. “Bone fractures from osteoporosis devastate men and women all over the globe and ongoing research is the only way to find ways to protect men from this disease.”

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Men With Low Testosterone Levels May Be At Increased Risk For Diabetes

admin — Sun, 13 May 2012 04:52:45 +0000

, a study suggests.
Scientists have found that low testosterone levels are linked to a resistance to insulin, the hormone that controls blood sugar levels.
The study is the first to directly show how low testosterone levels in fat tissue can be instrumental in the onset of Type 2 diabetes.
Testosterone is present throughout the body. Low testosterone levels are linked to
, a known risk factor for diabetes.
It acts on fat cells through molecules known as androgen receptors. These enable the testosterone to activate genes linked to obesity and diabetes.
The research showed that mice in which the function of testosterone in fat tissue was impaired were more likely to be insulin resistant than mice in which the role of testosterone was not hindered.
.
The findings from the University of Edinburgh could also help explain why older men are more at risk of developing diabetes, because testosterone levels fall in men as they age.
Dr Kerry McInnes, from the University of Edinburgh’s Endocrinology Unit, said: “We know that men with low testosterone levels are more likely to become obese, and as a develop diabetes. This study shows that low testosterone is a risk factor for diabetes no matter how much a person weighs. As men age their testosterone levels lower. This, along with increasing obesity, will increase the incidence of diabetes.”
The study, funded by Diabetes UK showed that mice, which did not have androgen receptors in fat tissue for testosterone to attach to, were more likely to show signs of insulin resistance than other mice.
Researchers found that mice without androgen receptors in fat tissue also became fatter than other mice and developed full insulin resistance when both types were fed a high-fat diet.
Scientists believe that a protein called RBP4 plays a crucial role in regulating insulin resistance when testosterone is impaired.
They found that levels of RBP4 were higher in mice in which the role of testosterone was impaired.
The Edinburgh team say that its findings could lead to the development of new treatments that regulate production of RBP4 and reduce the risk of diabetes in men with lower levels of testosterone.
Researchers are now planning to study patients with Type-2 diabetes to see if their levels of testosterone correlate with levels of RBP 4.
Dr Iain Frame, Director of Research at Diabetes UK, said: “We already know that low testosterone levels are associated with increased obesity and therefore with increased risk of developing Type 2 diabetes, but this study provides evidence that there can be increased risk even when body mass is not affected. Yet while testosterone-impaired mice developed insulin resistance whatever diet they were given, the effect was considerably more pronounced on those fed on a high fat diet. This reinforces Diabetes UK advice that a healthy balanced diet is important for everyone and particularly for those already at high risk of developing Type 2 diabetes.
“Further work is needed to translate these initial findings into clinical practice, as it is important to emphasise that results in mice may not necessarily have direct relevance for humans. But good basic research such as this represents early steps towards potential new treatments and we are pleased to see research we have funded producing useful results which may benefit people living with diabetes at some point in the future.”

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Testosterone Treatment Helps Obese Older Males Lose Weight, Other Health Gains Too

admin — Sun, 13 May 2012 03:31:46 +0000

Testosterone Treatment Helps Obese Older Males Lose Weight, Other Health Gains Too
Restoring low testosterone levels in older, overweight or obese men to normal levels results in dramatic weight loss and other health benefits, such as better blood pressure and blood glucose control,
Dr Farid Saad of the Medical Affairs Men’s Health Care at Bayer Pharma AG in Berlin, Germany, explained at the 19th European Congress on Obesity in Lyon, France.
is linked to lower levels of testosterone, which in turn induces weight gain. According to earlier research, men aged 45 years or older with low levels of testosterone are about twice as likely to be obese and suffer from type 2
as compared with age-matched controls.
Saad and team decided to examine the impact of normalizing blood testosterone levels in predominantly older men with low testosterone levels (hypogonadal) in a cumulative, prospective study.
They analyzed 251 men between the ages of 38 and 83 years, with an average age of 61. The men’s baseline testosterone levels ranged from between 0.14 to 3.5 ng/mL, with the cut-off point for testosterone treatment ? 3.5. ng/mL (12 nmol/L), a standard cut-off point for testosterone levels to be considered as ‘low’.
214 men were followed-up for at least 2 years, whilst 115 were followed-up for at least 5 years. All participants received testosterone undecanoate 1000 mg, with injections given at baseline, after 6 weeks and then every 12 weeks throughout the study period.
Those followed-up for 5 years lost, on average, 16kg with an average weight drop from 106 kg to 90 kg. The average waist circumference dropped from 107 cm or 42 inches to 98 cm or 38.5 inches, whilst the average body-mass index (BMI) dropped from 34 to 29, meaning that the men dropped from being classed as ‘obese’, which is a BMI of over 30 to ‘overweight’, which is a BMI of 25 to 30.
The participants also showed an improvement in other metabolic indicators, such as a drop of LDL or ‘bad’
(mg/dL) from 163 to 109, whilst triglycerides (mg/dL) went down from 276 to 189, and the average blood glucose measurements (mg/dL) fell from 103 to 94. In addition, the participants’ systolic blood pressure decreased from 153 to 137 mm Hg and diastolic from 93 to 79 mm Hg.
According to the researchers, there could be various factors responsible for the findings, given that increased testosterone levels improve energy and motivation to perform physical exercise and more movement in general. Testosterone also raises lean body mass, or fat free mass and enhances the patient’s energy levels.
in the participants – their risk of the disease did not rise above the average for other people of their age and general health.
, waist circumference, and blood pressure, and improved metabolic profiles. These improvements were progressive over the full 5 years of the study.”

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Greatly Reduced Sperm Viability Caused By Tetracycline Passes From Father To Son In Pseudoscorpions

admin — Sun, 29 Apr 2012 17:20:12 +0000

, researchers at the University of Nevada, Reno report that male pseudoscorpions treated with the
tetracycline suffer significantly reduced sperm viability and pass this toxic effect on to their untreated sons. They suggest that a similar effect could occur in humans and other species.
“This is the first research to show a transgenerational effect of antibiotics,” David Zeh, chair of the Department of Biology in the College of Science, said. “Tetracycline has a significant detrimental effect on male reproductive function and sperm viability of pseudoscorpions – reducing viability by up to 25 percent – and now we know that effect is passed on to the next generation. We didn’t see the effect in subsequent generations.”
The research involved a three-generation study of the pseudoscorpion,
Cordylochernes scorpioides,
a small scorpion-like arachnid. To control for genetic influences, in the first generation, brothers and sisters from each of 21 broods were either treated with weekly doses of tetracycline from birth to adulthood or were reared as untreated controls. Subsequent generations were not treated with tetracycline. The antibiotic had no effect on male or female body size, sperm number or female reproduction, they found.
In the article, lead author and assistant biology professor Jeanne Zeh surmises that tetracycline may induce epigenetic changes in male reproductive tissues that may be passed to sons – changes that do not alter the sequence of DNA but rather alter the way genes are expressed.
The broad-spectrum antibiotic tetracycline is commonly used in animal production, antimicrobial therapy, and for curing arthropods infected with bacterial endosymbionts such as Wolbachia. Despite more than six decades of therapeutic and agricultural use that has resulted in the evolution of widespread bacterial resistance, tetracycline is still commonly used as an additive in animal feed and as an accessible antimicrobial therapy in developing countries.

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Living In A City Center Doubles Risk Of Calcium Build-Up In Arteries

admin — Sun, 29 Apr 2012 07:29:02 +0000

City centre residents who took part in a study were almost twice as likely to suffer from coronary artery calcification (CAC), which can lead to
, than people who lived in less polluted urban and rural areas, according to research published in the May issue of the
Journal of Internal Medicine.
Researchers spoke to 1,225 men and women aged 50 and 60 years of age, including 251 (20%) who lived in the centres of major Danish cities.
Despite the fact that none of the participants showed any symptoms of heart disease, 43% of the total had CAC. The study also found that people who lived in city centres were 80% more likely to develop CAC than those living in other areas and that males, older participants, diabetics and smokers also faced higher risks.
“Our study aimed to evaluate the association between living in a city centre, which is often used by researchers to indicate exposure to air pollution, and the presence of coronary artery calcification in men and women showing no other symptoms of heart disease” explains lead author Dr Jess Lambrechtsen from the Department of Cardiology at Svendborg Hospital, Denmark.
Participants were selected at random from a national Government database of Danish adults and 69% agreed to take part and attend one of four regional hospitals in Southern Denmark. They filled out questionnaires about their medical conditions, prescribed medication, smoking habits and family history of heart disease. The clinical examination included height, weight, blood pressure, blood tests and scans.
Three per cent were excluded from the study because of previous heart problems, leaving 1,225 people who did not display any symptoms of heart disease. Of these, 47% were male and 53% were female and they were equally split between the 50 year-old and 60 year-old age groups. One in five were city centre dwellers, with this sample including a slightly higher percentage of females and people aged 60 (both 52%).
Air pollution levels were extracted from a national surveillance source. This showed that rates were approximately three times higher in city centres than other urban areas and seven times higher than in rural areas.
CAC was more common in people living in city centres, rather than urban or rural areas – in men (69% v 56%), women (42% v 30%), 50 year-olds (48% v 32%) and 60 year-olds (61% v 53%).
When the researchers looked at the odds ratio, this showed that people living in city centres were 80% more likely to develop CAC than those living in urban or rural areas.
Men were more than three times as likely as women to develop CAC, with a 220% higher odds risk.
when compared with those without diabetes (100% higher).
and a family history of heart disease both raised the odds by 50%.
“Our study shows that living in a city centre and traditional risk factors for heart disease were independently associated with the presence of CAC in a group of middle-aged subjects who did not display any symptoms” concludes Dr Lambrechtsen.
“The place where a person lives is often used as a surrogate for exposure to air pollution in research. In this study we found that, even after adjusting for demographic and clinical variables, where people lived was independently associated with CAC and that CAC levels were highest in people living in city centres.
“A number of factors can also influence CAC, such as noise and
levels and it could be assumed these would be higher in city centres. However, in this study stress levels, as measured by average blood pressure, were actually lower in city centre dwellers than people living in urban areas. Heart rates, another predictor of stress, were the same across the groups.
“The mechanisms by which air pollution may contribute to CAC are not well understood. But what is clear from this study is that the links between air pollution and CAC need further investigation.”

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New Treatment For Degenerative Vision Disorder Leber Hereditary Optic Neuropathy

admin — Tue, 24 Apr 2012 23:18:52 +0000

A research team, led by John Guy, M.D., professor of ophthalmology at Bascom Palmer Eye Institute of the University of Miami Miller School of Medicine, has pioneered a novel technological treatment for Leber Hereditary Optic Neuropathy (LHON), an inherited genetic defect that causes rapid, permanent, and bilateral loss of vision in people of all ages, but primarily males ages 20-40. Genetic mutations in the mitochondria (part of the cell that produces energy) cause the disorder. Currently, there is no cure for LHON. However, Guy and his team have successfully modified a virus and used it to introduce healthy genes into the mitochondria to correct the genetic defect. Using experimental models, they have proven that it is both safe and effective to replace mutated genes with healthy ones and that doing so prevents deterioration of the retinal cells that form the optic nerve. This research demonstrates that when efficiently introduced into mitochondria, normal DNA can correct a biochemical defect in cellular energy production and restore visual function.
“A wide range of other factors, including aging,
, and
, are also caused by mutations in the mitochondria,” said Dr. Guy. “This new approach shows the vast potential for genetic-therapy applications, while helping to address a significant cause of blindness.”
The healthy genes were delivered into the mitochondria via an innovative viral delivery system. Specifically, Guy redirected the adeno-associated virus (a small virus that infects humans but is not known to cause disease) to the mitochondria rather than to its typical target, the nucleus, where most genes are housed within the cell. He did so via a mitochondrial-targeting sequence (a peptide chain that directs the transport of a protein). This permitted the replacement of the defective mitochondrial gene with a healthy one, which then restored energy production to the affected ocular cells. Two National Institutes of Health/National Eye Institute grants, totaling $6.1 million funded this research, which began in 2007.
“Other research studies have shown that LHON patients who have lost their vision still have some sensitivity to light,” said Guy. “This indicated that if you can restore the functioning of those cells through gene therapy, those patients could see again.” In conjunction with his research, Guy explored why only about 50 percent of patients with the genetic mutation develop LHON, while others do not.
Known for exploring gene therapy as a potential treatment for diseases of the optic nerve, Guy holds several patents related to mitochondrial gene therapy biotechnology. His next steps will be to investigate incorporating all three genes that cause LHON into a single viral carrier and hopefully receive FDA approval to inject therapeutic genes into patients who have visual loss from mitochondrial disease.

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