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Scientists from The Universities of Manchester and Auckland have discovered widespread differences in metal levels in the brains of patients with Huntington鈥檚 Disease, a type of dementia, compared to a control group with healthy tissue.

In a study published in eBioMedicine, the elements, including selenium (a metalloid), sodium, potassium, magnesium, calcium, iron, zinc, copper, and manganese, were studied in 11 parts of the brain.

In particular, the scientists found substantial decreases in selenium levels in all 11 regions of the HD brains, calculating there was a high risk of having the disease when levels are low.

Increased sodium and potassium ratios were observed in every region except the substantia nigra, and many of the regions showed increased calcium and/or zinc levels. Localised decreases in iron, copper, and manganese were present in the globus pallidus, cerebellum, and substantia nigra, respectively.

Huntington's disease is a fatal condition that causes nerve cells in parts of the brain to gradually break down and die, resulting in memory lapses, stumbling, involuntary jerking, mood swings and , speaking and breathing.

Caused by a faulty gene inherited from a parent and often occurring between the ages of 30 and 50, its pathogenic mechanisms remain poorly understood.

There is currently no treatment for HD and according to the Alzheimer鈥檚 Society it affects around 8 in every 100,000 people in the UK.

The scientists analysed tissue donated by 9 people with HD after they died from the NZ Neurological Foundation Douglas Human Brain Bank at the University of Auckland.

Selenium is known to have an important role in protection against oxidative stress鈥攁n imbalance between free radicals and antioxidants which can damage organs and tissues and lead to HD.

It is also implicated in the dysfunction of mitochondria, one of the main powerhouses of human cells, which is also known to occur in the development of HD.

Sodium and potassium play an important role in the central nervous system by regulating the conduction of electrical nerve impulses.

Calcium, zinc, iron copper and manganese are also involved in processes as wide-ranging as gene expression, cell signalling, and cell death.

The areas with different levels of neurodegeneration were studied using cutting edge technology called inductively coupled plasma mass spectrometry.

Lead author Dr Melissa Scholefield said: 鈥淭his is the first known study which investigated metals simultaneously across many regions of the HD brain in the same cohort.

鈥淲e think the changes we found in their levels could contribute to several pathogenic mechanisms, including mitochondrial dysfunction, oxidative stress, and blood鈥揵rain barrier dysfunction, as shown by previous studies in mice.

鈥淗owever, we caution that it is dangerous to self-medicate with supplements; the blood-brain barrier could mean these could elements might build up in someone鈥檚 blood stream, with potentially toxic effects.鈥�

Principal Investigator Professor Garth Cooper said: 鈥淭he most striking finding is the deficiency of selenium in every part of the brain we studied.

鈥淏ecause selenium was deficient in all regions of the brain, that might mean it could be easier to one day target therapeutically, as it鈥檚 very hard to home in on specific brain regions.

鈥淔urther studies determining the time course, cause, and downstream effects of selenium alterations in HD may eventually present a potential therapeutic target for the treatment of this disease.

鈥滺owever, the results from the current human brain study should be treated as preliminary due to the relatively small size of our cohort.鈥�

The study was mainly funded by the Lee Trust.

The paper Widespread selenium deficiency in the brain of cases with Huntington鈥檚 disease presents a new potential therapeutic target is available