Cannabis could provide relief for Parkinson’s pain

As many as eight out of every 10 of those with Parkinson’s disease suffer from inexplicable pains that until now have been left untreated because they were thought to be an inevitable part of the progressive and eventually fatal neurological disease. Parkinson’s, a brain disorder that leads to tremors and difficulty with walking, coordination and movement, usually develops after age 50 and is one of the most common nervous system disorders of the elderly.

But new research at the Rabin Medical Center- Beilinson Campus has found that genetic factors explain such Parkinson’s pain, and that the new understanding will make unique treatments possible. Eight genes known to be involved in pain were examined in 237 Parkinson’s patients, according to a research paper published recently in the European Journal of Pain, and the observed variations were connected to functions of cannabis-like substances (cannabinoids) in the brain.

Research project head Prof. Ruth Djaldetti, a senior physician in the neurology department and head of the movement disorders clinic, said that the results support the treatment of Parkinson’s patients with medical marijuana.

Djaldetti encourages more research into the use of cannabis for pain relief.

There are some 20,000 people with Parkinson’s in Israel, and about 50 percent to 80% of them suffer from this previously unexplained and untreated pain. Djaldetti expects that in the future, gene mapping will make it possible to suit personalized medication to these patients.

THERAPY FOR PEANUTS?

A new study supported by the US National Institutes of Health suggests that sublingual (under-the-tongue) immunotherapy (SLIT) can reduce the allergic response to peanuts in adolescents and adults. SLIT is a treatment approach in which, under medical supervision, people place a small amount of allergen under the tongue to decrease their sensitivity to the allergen.

This is one of the first randomized, placebo-controlled studies to test the efficacy and safety of SLIT to treat peanut allergy and is one of several trials funded by the federal government to investigate immune-based approaches to preventing and treating food allergy. The results appeared recently in the Journal of Allergy and Clinical Immunology.

The study enrolled 40 people aged 12 to 37 with peanut allergy who were on a peanut-free diet. After an initial test to measure how much peanut powder they could eat without having an allergic reaction, participants received 44 weeks of daily therapy, followed by a second test. Fourteen of the 20 participants (70%) given peanut SLIT were able to consume at least 10 times more peanut powder than they could at the beginning of the study, compared with only three of the 20 participants (15%) given placebos.

After 68 weeks on peanut SLIT, participants could consume significantly more peanut powder without having an allergic reaction. Study investigators also observed that SLIT caused only minor side effects, such as itching in the mouth, suggesting that daily therapy is safe.

Although more work is needed, the investigators hope that SLIT could one day help protect people with peanut allergy from experiencing severe allergic reactions in cases of accidental exposure. The researchers caution that people should not try peanut SLIT on their own because any form of immunotherapy carries a significant risk for allergic reactions. The therapy should be administered only under the guidance of trained clinicians.

CALCIUM REGULATION IN CELLS STUDIED

All living cells keep their calcium concentration at a very low level. Since a small increase in calcium can affect many critical cellular functions (an elevated calcium concentration over an extended period can induce cell death), powerful cellular mechanisms ensure that calcium concentration quickly returns to its low level.

It is known that impairments of cellular calcium regulation underlie almost all neurodegenerative diseases. For example, age-related loss of calcium regulation was shown to promote cell vulnerability in Alzheimer’s disease.

In a study recently published in the Journal of Neuroscience, Hebrew University of Jerusalem researchers, along with others from Israel and the US, presented their findings of a previously undescribed cellular mechanism which is essential for keeping cellular calcium concentration low. This mechanism operates together with other already-characterized mechanisms.

Dr. Shirley Weiss and Prof. Baruch Minke of HU’s Institute of Medical Research Israel-Canada and the Edmond and Lily Safra Center for Brain Sciences characterized this mechanism using photoreceptor cells of the fruit fly, which is a powerful model for studying basic biological processes.

They found that calphotin, a calcium buffer, operates by sequestering elevated calcium concentration. Genetic elimination of calphotin led to a light-induced rise in cellular calcium for an abnormally extended time, leading to retinal photoreceptor degeneration in the fruit flies. The researchers stress that this kind of research, leading to a better understanding of the fundamental mechanisms underlying cellular calcium regulation, is critical for the development of new drugs and treatments for neurodegenerative diseases.

GREEN IS BEAUTIFUL

Women who drink green tea may lower their risk of developing some digestive system cancers, especially cancers of the stomach/esophagus and colon/rectum, according to a study led by researchers from Vanderbilt-Ingram Cancer Center in Tennessee. The study was headed by Prof. Sarah Nechuta and published in the American Journal of Clinical Nutrition. To determine green tea’s impact on cancer risk, the investigators surveyed women enrolled in the Shanghai Women’s Health Study, a population- based study of approximately 75,000 middle-aged and older Chinese women. During the initial interview participants were asked if they drank tea, the type of tea consumed and how much they consumed. Most of the Chinese women reported drinking primarily green tea.

The researchers found that regular tea consumption, defined as tea consumption at least three times a week for more than six months, was associated with a 17 percent reduced risk of all digestive cancers combined. A further reduction in risk was found to be associated with an increased level of tea drinking. Specifically, those who consumed about two to three cups per day (at least 150 grams of tea monthly) had a 21% reduced risk of digestive system cancers, especially stomach/esophageal and colorectal cancers.

“For all digestive system cancers combined, the risk was reduced by 27% among women who had been drinking tea regularly for at least 20 years,” said Nechuta. “For colorectal cancer, risk was reduced by 29% among the long-term tea drinkers. These results suggest long-term cumulative exposure may be particularly important.” Tea contains polyphenols or natural chemicals that include catechins like EGCG and ECG. Catechins have antioxidant properties and may inhibit cancer by reducing DNA damage and blocking tumor cell growth and invasion.

EARLIER MENOPAUSE, EARLIER MEMORY TROUBLES Women who go into “surgical menopause” due to removal of their ovaries (and sometimes the uterus) at an earlier age may be at increased risk of decline in memory and cognitive skills, according to a study to be presented at the American Academy of Neurology’s 65th Annual Meeting in San Diego next month. Menopause begins naturally around the age of 50.

“While we found a link between surgical menopause and thinking and memory decline, women on longer hormone replacement therapies [HRT] had slower declines,” said study author Dr. Riley Bove of Boston’s Harvard Medical School. “Since HRT is widely available, our research raises questions as to whether these therapies have a protective effect against cognitive decline and whether women who experience early surgical menopause should be taking hormone replacement therapies afterward.”

The study included 1,837 women between the ages of 53 and 100 participating a memory and aging project at Rush University Medical Center in Chicago. Of those, 33% had undergone surgical menopause. The women were given several types of tests that measured thinking skills and memory. It was found that among women who underwent surgical menopause, the earlier they underwent the surgery, the faster the decline in their longterm memory related to concepts and ideas, memory that relates to time and place and in overall thinking abilities.