Brain inflammation linked to more severe Parkinson’s symptoms

Reversing inflammation in the fluid surrounding the brain’s cortex may provide a solution to the complex riddle of Parkinson’s, according to researchers who have found a link between pro-inflammatory biomarkers and the severity of symptoms such as fatigue, depression and anxiety in patients with the chronic disease.

Lena Brundin of Michigan State University’s College of Human Medicine was part of a research team that measured inflammatory markers found in cerebrospinal fluid samples of Parkinson’s patients and members of a control group.

‘The degree of neuroinflammation was significantly associated with more severe depression, fatigue, and cognitive impairment even after controlling for factors such as age, gender and disease duration,’ said Brundin, an associate professor in the college and a researcher with the Van Andel Institute.

‘By investigating associations between inflammatory markers and non-motor symptoms we hope to gain further insight into this area, which in turn could lead to new treatment options.’
Inflammation in the brain long has been suspected to be involved in the development of Parkinson’s disease, specifically in non-motor symptoms such as depression, fatigue and cognitive impairment. Recent research suggests inflammation could drive cell death and that developing new drugs that target this inflammation might slow disease progression.

Parkinson´s disease is the second most common degenerative disorder of the central nervous system; the causes of the disease and its development are not yet fully understood.

‘The few previous studies investigating inflammatory markers in the cerebrospinal fluid of Parkinson’s patients have been conducted on comparatively small numbers of subjects, and often without a healthy control group for comparison,’ Brundin said.

In the study, 87 Parkinson’s patients were enrolled between 2008 and 2012. For the control group, 37 individuals were recruited. Participants underwent a general physical exam and routine blood screening. Researchers looked at the following markers: C-reactive protein, interleukin-6, tumor necrosis factor-alpha, eotaxin, interferon gamma-induced protein-10, monocyte chemotactic protein-1 and macrophage inflammatory protein 1-β.

The study was carried out in collaboration with researchers from Lund University in Sweden, Skåne University Hospital in Sweden and the Mayo Clinic College of Medicine in Florida. Michigan State University

Scientists identify ALS disease mechanism

Researchers have tied mutations in a gene that causes amyotrophic lateral sclerosis (ALS) and other neurodegenerative disorders to the toxic build-up of certain proteins and related molecules in cells, including neurons. The research offers a new approach for developing treatments against these devastating diseases.
Scientists at St. Jude Children’s Research Hospital and the University of Colorado, Boulder, led the work.
The findings provide the first evidence that a gene named VCP plays a role in the break-up and clearance of protein and RNA molecules that accumulate in temporary structures called RNA granules. RNAs perform a variety of vital cell functions, including protein production. RNA granules support proper functioning of RNA.
In ALS and related degenerative diseases, the process of assembling and clearing RNA granules is impaired. The proteins and RNAs associated with the granules often build up in nerve cells of patients. This study shows how mutations in VCP might contribute to that process and neurodegenerative disease.
‘The results go a long way to explaining the process that links a variety of neurodegenerative diseases, including ALS, frontotemporal dementia and related diseases of the brain, muscle and bone known as multisystem proteinopathies,’ said the study’s co-corresponding author, J. Paul Taylor, M.D., Ph.D., a member of the St. Jude Department of Developmental Neurobiology. Roy Parker, Ph.D., of the University of Colorado’s Department of Chemistry and Biochemistry and the Howard Hughes Medical Institute (HHMI), is the other corresponding author. St Jude Children’s Research Hospital

Researchers discover a potential cause of autism

Problems with a key group of enzymes called topoisomerases can have profound effects on the genetic machinery behind brain development and potentially lead to autism spectrum disorder (ASD), according to research. Scientists at the University of North Carolina School of Medicine have described a finding that represents a significant advance in the hunt for environmental factors behind autism and lends new insights into the disorder’s genetic causes.

‘Our study shows the magnitude of what can happen if topoisomerases are impaired,’ said senior study author Mark Zylka, PhD, associate professor in the Neuroscience Center and the Department of Cell Biology and Physiology at UNC. ‘Inhibiting these enzymes has the potential to profoundly affect neurodevelopment — perhaps even more so than having a mutation in any one of the genes that have been linked to autism.’

The study could have important implications for ASD detection and prevention.

‘This could point to an environmental component to autism,’ said Zylka. ‘A temporary exposure to a topoisomerase inhibitor in utero has the potential to have a long-lasting effect on the brain, by affecting critical periods of brain development. ‘

This study could also explain why some people with mutations in topoisomerases develop autism and other neurodevelopmental disorders.

Topiosomerases are enzymes found in all human cells. Their main function is to untangle DNA when it becomes overwound, a common occurrence that can interfere with key biological processes.

Most of the known topoisomerase-inhibiting chemicals are used as chemotherapy drugs. Zylka said his team is searching for other compounds that have similar effects in nerve cells. ‘If there are additional compounds like this in the environment, then it becomes important to identify them,’ said Zylka. ‘That’s really motivating us to move quickly to identify other drugs or environmental compounds that have similar effects — so that pregnant women can avoid being exposed to these compounds.’

Zylka and his colleagues stumbled upon the discovery quite by accident while studying topotecan, a topoisomerase-inhibiting drug that is used in chemotherapy. Investigating the drug’s effects in mouse and human-derived nerve cells, they noticed that the drug tended to interfere with the proper functioning of genes that were exceptionally long — composed of many DNA base pairs. The group then made the serendipitous connection that many autism-linked genes are extremely long.

‘That’s when we had the ‘Eureka moment,’’ said Zylka. ‘We realised that a lot of the genes that were suppressed were incredibly long autism genes.’

Of the more than 300 genes that are linked to autism, nearly 50 were suppressed by topotecan. Suppressing that many genes across the board — even to a small extent — means a person who is exposed to a topoisomerase inhibitor during brain development could experience neurological effects equivalent to those seen in a person who gets ASD because of a single faulty gene.

The study’s findings could also help lead to a unified theory of how autism-linked genes work. About 20 percent of such genes are connected to synapses — the connections between brain cells. Another 20 percent are related to gene transcription — the process of translating genetic information into biological functions. Zylka said this study bridges those two groups, because it shows that having problems transcribing long synapse genes could impair a person’s ability to construct synapses.

‘Our discovery has the potential to unite these two classes of genes — synaptic genes and transcriptional regulators,’ said Zylka. ‘It could ultimately explain the biological mechanisms behind a large number of autism cases.’ University of North Carolina School of Medicine

Brain scans could predict response to antipsychotic medication

Researchers from King’s College London and the University of Nottingham have identified neuroimaging markers in the brain which could help predict whether people with psychosis respond to antipsychotic medications or not.
In approximately half of young people experiencing their first episode of a psychosis (FEP), the symptoms do not improve considerably with the initial medication prescribed, increasing the risk of subsequent episodes and worse outcome. Identifying individuals at greatest risk of not responding to existing medications could help in the search for improved medications, and may eventually help clinicians personalise treatment plans.
In a study, researchers used structural Magnetic Resonance Imaging (MRI) to scan the brains of 126 individuals – 80 presenting with FEP, and 46 healthy controls. Participants had an MRI scan shortly after their FEP, and another assessment 12 weeks later, to establish whether symptoms had improved following the first treatment with antipsychotic medications.
The researchers examined a particular feature of the brain called ‘cortical gyrification’ – the extent of folding of the cerebral cortex and a marker of how it has developed. They found that the individuals who did not respond to treatment already had a significant reduction in gyrification across multiple brain regions, compared to patients who did respond and to individuals without psychosis. This reduced gyrification was particularly present in brain areas considered important in psychosis, such as the temporal and frontal lobes. Those who responded to treatment were virtually indistinguishable from the healthy controls.
The researchers also investigated whether the differences could be explained by the type of diagnosis of psychosis (eg. with or without affective symptoms, such as depression or elated mood). They found that reduced gyrification predicted non-response to treatment independently of the diagnosis.
Dr Paola Dazzan from the Department of Psychosis Studies at King’s College London’s Institute of Psychiatry, and senior author of the paper, says: ‘Our study provides crucial evidence of a neuroimaging marker that, if validated, could be used early in psychosis to help identify those people less likely to respond to medications. It is possible that the alterations we observed are due to differences in the way the brain has developed early on in people who do not respond to medication compared to those who do.’
She continues:’There have been few advances in developing novel anti-psychotic drugs over the past 50 years and we still face the same problems with a sub-group of people who do not respond to the drugs we currently use. We could envisage using a marker like this one to identify people who are least likely to respond to existing medications and focus our efforts on developing new medication specifically adapted to this group. In the longer term, if we were able to identify poor responders at the outset, we may be able to formulate personalised treatment plans for that individual patient.’
Dr Lena Palaniyappan from the University of Nottingham adds: ‘All of us have complex and varying patterns of folding in our brains. For the first time we are showing that the measurement of these variations could potentially guide us in treating psychosis. It is possible that people with specific patterns of brain structure respond better to treatments other than antipsychotics that are currently in use. Clearly, the time is ripe for us to focus on utilising neuroimaging to guide treatment decisions.’ King’s College London

Scientists find new gene linked to ovarian cancer

Cancer Research UK scientists have found a gene in mice that could protect against ovarian cancer and, if faulty, may increase the chance of developing the disease, according to research.
This gene, known as Helq, helps repair any damage to DNA that happens when it is copied as cells multiply. So if the gene is missing or faulty, DNA errors could mount up, increasing the chance of cancer developing.
The team, from Cancer Research UK’s London Research Institute, found that mice without either of the two copies of the Helq gene were twice as likely to develop ovarian tumours, as well as becoming less fertile. And even losing just a single copy of the Helq gene was enough to cause a mouse to develop more tumours.
Dr Simon Boulton, senior author from Cancer Research UK’s London Research Institute, said: ‘Our findings show that if there are problems with the Helq gene in mice it increases the chance of them developing ovarian and other tumours. This is an exciting finding because this might also be true for women with errors in Helq, and the next step will be to see if this is the case.
‘If it plays a similar role in humans, this may open up the possibility that, in the future, women could be screened for errors in the Helq gene that might increase their risk of ovarian cancer.’
Dr Julie Sharp, Cancer Research UK’s senior science information manager, said: ‘This study pulls together clues from a series of experiments building a picture of cell faults that could lead to ovarian cancer in women.
‘Ovarian cancer can be hard to diagnose early and treat successfully so the more we know about the causes of the disease, the better equipped we will be to detect and treat it.’ Cancer Research UK

Inactivation of taste genes causes male sterility

Scientists from the Monell Center report the surprising finding that two proteins involved in oral taste detection also play a crucial role in sperm development.
‘This paper highlights a connection between the taste system and male reproduction,’ said lead author Bedrich Mosinger, MD, PhD, a molecular biologist at Monell. ‘It is one more demonstration that components of the taste system also play important roles in other organ systems.’
While breeding mice for taste-related studies, the researchers discovered that they were unable to produce offspring that were simultaneously missing two taste-signalling proteins.
As reported online, the critical proteins were TAS1R3, a component of both the sweet and umami (amino acid) taste receptors, and GNAT3, a molecule needed to convert the oral taste receptor signal into a nerve cell response.
Breeding experiments determined that fertility was affected only in males. Both taste proteins had previously been found in testes and sperm, but until now, their function there was unknown.
In order to explore the reproductive function of the two proteins, the research team engineered mice that were missing genes for the mouse versions of TAS1R3 and GNAT3 but expressed the human form of the TAS1R3 receptor. These mice were fertile.
However, when the human TAS1R3 receptor was blocked in the engineered mice by adding the drug clofibrate to the rodents’ diet, thus leaving the mice without any functional TAS1R3 or GNAT3 proteins, the males became sterile due to malformed and fewer sperm. The sterility was quickly reversed after clofibrate was removed from the diet.
Clofibrate belongs to a class of drugs called fibrates that frequently are prescribed to treat lipid disorders such as high blood cholesterol or triglycerides. Previous studies from the Monell team had revealed that it is a potent inhibitor of the human, but not mouse, TAS1R3 receptor.
Noting the common use of fibrates in modern medicine and also the widespread use in modern agriculture of the structurally-related phenoxy-herbicides, which also block the human TAS1R3 receptor, Mosinger speculates that these compounds could be negatively affecting human fertility, an increasing problem worldwide.
He in turn notes positive implications related to the research. ‘If our pharmacological findings are indeed related to the global increase in the incidence of male infertility, we now have knowledge to help us devise treatments to reduce or reverse the effects of fibrates and phenoxy-compounds on sperm production and quality. This knowledge could further be used to design a male non-hormonal contraceptive.’
Previous work from Monell and other groups has shown that some taste genes can be found in other parts of the body, including stomach, intestines, pancreas, lungs, and brain, where they are increasingly thought to have important physiological functions. Monell Center

New pathway in blood vessel inflammation and disease

Case Western Reserve researchers have identified a genetic factor that blocks the blood vessel inflammation that can lead to heart attacks, strokes and other potentially life-threatening events.
The breakthrough involving Kruppel-like factor (KLF) 15 is the latest in a string of discoveries from the laboratory of professor of medicine Mukesh K. Jain, MD, FAHA, that involves a remarkable genetic family. Kruppel-like factors appear to play prominent roles in everything from cardiac health and obesity to metabolism and childhood muscular dystrophy.
School of Medicine instructor Yuan Lu, MD, a member of Jain’s team, led the study involving KLF-15 and its role in inflammation. Lu and colleagues observed that KLF-15 blocks the function of a molecule called NF-kB, a dominant factor responsible for triggering inflammation.
This finding reveals a new understanding of the origins of inflammation in vascular diseases, and may eventually lead to new, targeted treatment options.
‘It had been suspected that smooth muscle cells were related to inflammation, but it hadn’t been pinpointed and specifically linked to disease,’ said Jain, Ellery Sedgwick Jr. Chair and director, Case Cardiovascular Research Institute at Case Western Reserve School of Medicine. Jain also is chief research officer for the Harrington Heart & Vascular Institute at University Hospitals Case Medical Center. ‘This work provides cogent evidence that smooth muscle cells can initiate inflammation and thereby promote the development of vascular disease.’
Smooth muscle cells are only one of two major cell types within blood vessels walls. The other cell type, endothelium, has traditionally taken the blame for inflammation, but Jain’s study suggests that both cells are critically important in the development of vascular disease.
The researchers learned that expression of this factor appeared mainly in smooth muscle cells and that levels were markedly reduced in atherosclerotic human blood vessels. To establish causality, the team generated genetically-modified mice where they deleted KLF-15 gene in smooth muscle cells.
‘We expected to see more proliferation of the smooth muscle cells as this is a common response of this cell type in disease,’ Lu said, first author on the paper. ‘Instead, we were surprised to see rampant vascular inflammation and hyper activated NF-kB, the master regulator of inflammation.’
The results offer hope for the development of specific anti-inflammatory therapies for vascular disease. Cholesterol-lowering drugs such as statins have some anti-inflammatory effects, but despite their widespread use, the burden of vascular disease remains high. As statins’ primary role is to lower cholesterol levels, developing additional or more potent anti-inflammatory therapies are needed to compliment statins’ important function.
Jain’s previous research of the KLF family of genetic factors revealed regulator functions in blood vessels. KLF4 was shown to potently inhibit inflammation in the endothelium, the other major cell type in vessels. The current work is first to establish a role for these factors in smooth muscle inflammation. Case Western Reserve University School of Medicine

Protein link to initial tumour growth in several cancers

A team led by scientists from The Scripps Research Institute (TSRI) have shown that a protein once thought to inhibit the growth of tumours is instead required for initial tumour growth. The findings could point to a new approach to cancer treatment.
The focus of the study was angiomotin, a protein that co-ordinates cell migration, especially during the start of new blood vessel growth and proliferation of other cell types.

‘We were the first to describe angiomotin’s involvement in cancer,’ said Joseph Kissil, a TSRI associate professor who led the studies. ‘ And while some following studies found it to be inhibiting, we wanted to clarify its role by using both cell studies and animal models. As a result, we have now found that it is not an inhibitor at all, but instead is required for Yap to produce new tumour growth.’

Yap (Yes-associated-Protein) is a potent oncogene that is over-expressed in several types of tumours.

In addition to identifying angiomotin’s critical role in tumour formation, Kissil and his colleagues found the protein is active within the cell nucleus. Earlier cell studies focused on the function of the protein at the cell membrane.

‘This pathway, which was discovered less than a decade ago, appears to regulate processes that are closely linked to cancer,’ Kissil said. ‘The more we study it, the more we see its involvement.’ Scripps Florida

Psychological effects of genetic testing for risk of weight gain

Obesity gene testing does not put people off weight loss and may help to reduce self-blame, according to a new study by researchers from the Health Behaviour Research Centre at UCL.

Previous studies have shown that genes play a role in a person’s risk of becoming overweight. One gene, called FTO, has been found to have the biggest influence so far.

FTO has two variants, one associated with greater risk of weight gain (A) and one associated with lower risk (T). One in two people carries at least one copy of the A variant. People who inherit two A variants (one from their mother and one from their father) are 70% more likely to become obese than those with two T variants. Even those who inherit one have a higher weight than those with two T variants.

Researchers can now use a gene test for FTO (although this is not yet commercially available). However, it was not known how people would react to finding out the results of the genetic test.
Regardless of gene status or weight, all the volunteers recognised that both genes and behaviour are important for weight control. The results indicate that people are unlikely to believe that genes are destiny and stop engaging with weight control once they know their FTO status.
Some clinicians thought it would help people to become motivated to manage their weight. Others thought that the ‘genes as destiny’ perspective might mean people felt there was nothing they could do about their weight. If people responded fatalistically it could be harmful because diet and exercise are still very important for health and weight control, perhaps even more so if a person is ‘battling against their biology’.

UCL’s Professor Jane Wardle and Susanne Meisel decided to test a small number of volunteers (18) for their FTO status and interview them about their experience. The sample of volunteers included men and women, who spanned the weight range from underweight to obese.

They found that the volunteers were very enthusiastic about receiving their genetic test result. Those who struggled with their weight said that the genetic test result was helpful because it removed some of the emotional stress attached to weight control and relieved some of the stigma and self-blame.

No one reported a negative reaction to the genetic test result, or said it made them feel there was nothing they could do to about their weight.

Susanne Meisel, who led the study said: ‘These results are encouraging. Regardless of gene status or weight, all the volunteers recognised that both genes and behaviour are important for weight control. The results indicate that people are unlikely to believe that genes are destiny and stop engaging with weight control once they know their FTO status. Although they knew that FTO’s effect is only small, they found it motivating and informative. We are now doing a larger study to confirm whether more people react in the same way.’ University of College London

3 out of every 4 cases of bladder cancer display mutations in the same gene

Researchers from the Spanish National Cancer Research Centre (CNIO) have discovered that more than 70% of bladder tumours display somatic mutations in the TERT gene (telomerase reverse transcriptase). The TERT gene is involved in the protection of DNA and in cellular ageing processes and cancer. These results make this gene the most mutated in these tumours.
The study was led by Francisco X. Real, head of the Epithelial Carcinogenesis Group at CNIO, together with Nuria Malats, the head of the Genetic & Molecular Epidemiology Group at CNIO, as well as other European groups, especially Yves Allory, a pathologist at the Mondor Hospital (Créteil, Paris, France), who is on a sabbatical year with Real and Malats’s groups at CNIO, and Ellen Zwarthoff’s group at the Erasmus Medical Centre in Rotterdam.
The conclusions come from an exhaustive genetic and molecular study of more than 450 patients diagnosed with bladder cancer. Among the cases explored are both indolent tumours and more aggressive tumours and, therefore, those most likely to develop localised or spreading metastasis in the organism.

‘When we analysed the frequency of TERT mutations in this group of patients, we observed that there was no correlation between the presence of mutations and the aggressiveness of the tumour or the survival or the patients’, says Real. The authors’ description in the article explains that: ‘The fact that these mutations are present in any phase of the urothelial tumoural process suggests that they occur in an early phase during carcinogenesis’.
The product of the TERT gene is a protein, the reverse transcriptase of the telomerase complex, which increases the length of telomeres, protective structures for genetic material located at the ends of chromosomes and associated with cellular ageing.
‘How TERT mutations affect the length of the telomeres and encourage carcinogenesis still needs to be discovered’, says Real, adding that: ‘We believe that they could increase the gene expression, but additional studies are necessary’. EurekAlert