Friday, November 5, 2010

Women & Alzheimer's

A new report by the Alzheimer's Foundation shows that women are not only the primary unpaid caregivers and advocates for those with the disease, they are also becoming victims of the disease itself in disproportionate numbers.
According to a recent poll which gathered information from 3,118 adults nationwide, including more than 500 Alzheimer caregivers:

  •    60% of Alzheimer's caregivers are women.
  •    Of those women, 68% report they have emotional stress from care giving.
  •    Nearly half of these 68% rate their stress as a "5" on a scale of "1" to "5."
  •    57% of all caregivers, including 2/3 of the women, admit they fear getting Alzheimer's.
  •    4 in 10 caregivers say they had no choice about their new role.

The problem is that many of those caregivers are now being diagnosed with the disease. Women suffer disproportionately from various forms of dementia, including Alzheimer's: by some estimates sixty-five percent of those currently  suffering from Alzheimer's are women. Though women are only slightly more likely to develop Alzheimer's than men, its prevalence among women is twice as high simply because women live longer, with a life expectancy of 80 years versus 75 for men. Half of all women over 85 in the U.S. will eventually develop this disease.

New research shows that hormonal differences may increase the risk of Alzheimer's in women. One study, for instance, has found that hormone replacement therapy can increase a person's risk of developing dementia. Another study found that high or low levels of a thyroid hormone called thyrotropin may be associated with an increased risk of Alzheimer's disease in women. Estrogen may also play a role.
Gender also seems to dictate which risk factors matter more in the development of dementia. A French study found that men who had suffered a stroke were three times more likely to develop dementia, while stroke seemed to have no effect at all in women. Yet women prone to depression were twice as likely to suffer from dementia, and women unable to live without assistance due to an inability to perform routine tasks were 3.5 times more likely to develop dementia.

Alzheimer's develops differently in men and women, and they exhibit different symptoms of dementia: men with Alzheimer's disease tend to develop more aggression than women do as the disease progresses. They also tend to wander and perform socially inappropriate actions more frequently than women diagnosed with Alzheimer's. Women on the other hand tend to become more reclusive and emotionally unstable. They hoard items more often than men do, refuse help more often, and exhibit laughter or crying at inappropriate moments. Women also seem more vulnerable to depression and to suffering from delusions.

Because baby boomers are aging and because the population of those over age 85 is reaching record levels in the U.S., the number of people with Alzheimer's is expected to more than triple by 2050. By that time approximately 8 million women will have AD in the USA.
The FDA has only approved two types of medication to improve cognitive symptoms of Alzheimer's disease such as memory loss, according to the Alzheimer's Association. But there is no treatment that stops or reverses its progression. In America about $6 billion of funding is funneled to cancer research, and $4 billion is spent on heart disease research. Only $500 million has been allocated to Alzheimer's research, according to the Alzheimer's Association.

Fortunately there are steps women -and men- can take to protect themselves.
Studies show that getting regular exercise, eating lots of fruits, vegetables and fish, and keeping the mind active can help ward off the disease. So can taking a pass on hormone replacement therapy, which can double the risk of Alzheimer's. If they start showing signs of confusion or memory loss, women can slow Alzheimer's progression by getting diagnosed and taking medication early.
For more information on Alzheimer's disease and dementia, visit .

Wednesday, June 2, 2010

Advances in Gene Therapy: A new generation of Antisense drugs may hold the key to treating our most debilitating diseases.

Gene therapy is the insertion of genes into cells and tissues to treat disease. The gene, which is a stretch of DNA or RNA, is injected into a vector -the delivery vehicle- such an Adenovirus: the virus (with a now modified DNA) is absorbed by a targeted cell, where the cell nucleus alters its proteins using the new gene. Although the technology is still in its infancy, it has shown great promise in treating diseases such as Cancer and HIV/AIDS, as well as deadly viruses.

Pushing modern technology even further, Antisense Therapy utilizes a synthesized strand of nucleic acid which bonds to the mRNA produced by a specific gene and inactivates it, in effect acting like a micro switch which can alter the way specific cells produce proteins or prevent them from reproducing.

Currently there are no available vaccines or therapies for Ebola. Antisense drugs are useful against viral diseases because they are designed to enter cells and eliminate viruses by preventing their replication. The drugs, which act by blocking critical viral genetic sequences, may be more potent than anti-virals such as protease inhibitors that seek to inhibit a protein needed for viral replication. In a new study using Antisense drugs containing called small interfering RNAs (siRNAs), researchers targeted the L protein which is critical for Ebola virus replication. Using a proprietary technology called SNALP, or stable nucleic acid-lipid particles, to deliver the therapeutics to disease sites in animal models infected with the most potent strain of Ebola they were able to effectively inhibit the growth of the virus in 3 out of 4 infected rhesus monkeys.

In cancer studies Antisense drugs have shown the ability to target the proto-oncogenes found in normal cells. These genes, when mutated or expressed at high levels, help turn a normal cell into a tumor cell. Other Antisense drugs can inhibit the protein kinase C-alpha, which signals the cell to divide in other cancers. Scientists have discovered a way to improve the effectiveness of antisense cancer drugs by attaching multiple strands of antisense DNA to the surface of a gold nanoparticle (forming an "antisense nanoparticle"). The DNA then becomes more stable and can bind to the target messenger RNA (mRNA) more effectively.

In HIV/AIDS treatment, researchers have been conducting clinical trials using a HIV lentiviral vector, which has the unique ability to integrate into the genome of non-dividing cells( other Retroviruses can infect only dividing cells). Because "short" antisense -such as ribozymes or RNAi- may be more likely to result in HIV strains that are resistant to the therapy, these new drugs contain a very long antisense that inhibits HIV replication and debilitates HIV's ability to resist the treatment. The antisense lies inactive in a patient’s white blood cells (specifically the CD4+cells), waiting for HIV to enter that cell. When HIV does enter, replication of HIV within that cell activates the vector, which then binds to and destroys the HIV.

Ongoing clinical trials are attempting to determine if patients can go off antiretroviral drugs permanently: while the data from this trial is still not complete, the results are very encouraging.

With the completion of the Human Genome Project draft in 2003, researchers have been given detailed knowledge of the human genome which will provide new avenues for advances in medicine and biotechnology. This information can provide a deeper understanding of the disease processes at the level of molecular biology, and will potentially determine many new therapeutic procedures.

Given the established importance of DNA in molecular biology and its central role in determining the fundamental operation of cellular processes, it is likely that expanded knowledge in this area will facilitate medical advances in numerous areas of clinical interest that may not have been possible without them.

Thursday, January 21, 2010

Don’t Have a Seat: New study shows that we spend too much time on our butts and it’s killing us.

How much time do you spend sitting? Think about it: an average American office worker gets out of bed, and then sits in a car on the way to work where they sit down at their desk. Maybe you’ll go out for lunch and sit at a table. Back to work, a commute home, then a few hours sitting in front of the TV before bed.
A new study published in the Journal of the American Heart Association has found that every hour per day spent sitting without physical activity increases a person's risk of dying from heart disease by almost one-fifth, regardless of how physically fit or unfit they are. "Even if someone has a healthy body weight, sitting for long periods of time still has an unhealthy influence on their blood sugar and blood fats," according to Professor David Dunstan, head of the Physical Activity laboratory at Australia’s Baker IDI Heart and Diabetes Institute.
The study measured the intensity of physical activity in 168 subjects over seven days. It found that regardless of how much moderate-to-vigorous exercise they did or their total sedentary time, those who took more breaks from sitting had lower waist circumferences, lower body mass indexes and lower levels of triglycerides and glucose in blood. Higher levels of triglycerides, or blood lipids, have been linked to a heightened risk of heart disease and stroke. High blood glucose levels are linked to the development of diabetes, which itself is a major risk factor for heart disease.
The studies found that the enzymes responsible for breaking down fat are suppressed when a person is sitting instead of standing.

"To hold a body that weighs [77 kilograms] upright takes a fair amount of energy from muscles," he said. "There is a large amount of energy associated with standing every day that can't easily be compensated for by 30 to 60 minutes in the gym."
His studies found that the enzymes responsible for breaking down fat are suppressed when a person is sitting instead of standing.

But the good news is that pottering about the house or gently walking around the office while on the phone might be enough to keep you fit: regardless of how much moderate-to-vigorous exercise they did or their total sedentary time, those who took more breaks from sitting had lower waist circumferences, lower body mass indexes and lower levels of triglycerides and glucose in blood. In fact, the sheer effort of standing up is enough to double the metabolic rate and the amount of calories burnt.

"If you stand up, you are much more likely to end up pacing or pottering around and that seems to make a crucial difference."