A distinctive chemical signature in the brain may help explain why some patients with multiple system atrophy develop severe problems with balance, coordination and speech, while others are affected predominantly by Parkinson-like movement symptoms. In a study published in npj Parkinson’s Disease, researchers report that the cerebellar subtype of multiple system atrophy, known as MSA-C, is marked by regional reductions in high-energy phosphorus metabolites. The finding points to a measurable disturbance in the brain’s energy economy and could provide a new way to distinguish disease subtypes that can look similar during the earliest stages of illness.
Multiple system atrophy is a rare, progressive neurodegenerative disorder caused by the gradual failure of several interconnected systems in the brain and autonomic nervous system. It belongs to the family of synucleinopathies, diseases in which the protein alpha-synuclein accumulates abnormally inside cells called oligodendrocytes. Unlike Parkinson’s disease, which primarily targets particular circuits involved in movement, multiple system atrophy can damage motor control, coordination, blood-pressure regulation, bladder function and other automatic processes. The disorder is usually divided into MSA-C, in which cerebellar dysfunction dominates, and MSA-P, in which Parkinsonian features such as rigidity, slowness and tremor are more prominent.
The cerebellum acts as the brain’s precision-control center. It does not initiate movement in the same way as the motor cortex, but it constantly compares intended actions with actual performance, helping the body maintain balance, timing and accuracy. When cerebellar networks deteriorate, patients may develop ataxia, an inability to coordinate movements smoothly, along with an unsteady gait, slurred speech and difficulty controlling the eyes or limbs. Because early MSA-C symptoms can overlap with other forms of ataxia, clinicians often face a difficult diagnostic problem. A biological signal that reveals the affected brain region before the full clinical picture emerges could therefore have considerable value.
The new work focuses on phosphorus-containing molecules that serve as indicators of cellular energy production and membrane biology. The most important high-energy phosphorus compounds include adenosine triphosphate, or ATP, the immediate energy currency used by neurons, and phosphocreatine, a rapidly available energy reservoir that helps stabilize ATP levels when demand changes. Phosphorus magnetic resonance spectroscopy, commonly called 31P-MRS, can measure these and related compounds inside living tissue. The technique uses the magnetic properties of the phosphorus-31 isotope to create a metabolic profile rather than a conventional anatomical image, allowing researchers to study how brain chemistry changes in specific regions.
According to the study, individuals with the cerebellar form of multiple system atrophy showed a regional reduction in high-energy phosphorus metabolites, particularly in areas associated with cerebellar function. This pattern is important because it suggests that MSA-C is not defined solely by visible tissue loss or abnormal protein accumulation. It also involves a localized failure of energy-related chemistry. Neurons consume enormous amounts of ATP to maintain electrical gradients, communicate across synapses and transport materials along their long cellular processes. If mitochondrial energy production becomes inefficient, or if energy demand can no longer be met, vulnerable neural circuits may begin to malfunction even before extensive structural degeneration becomes obvious on routine scans.
A reduction in phosphorus metabolites can reflect several biological processes rather than a single mechanism. Lower ATP or phosphocreatine levels may indicate impaired mitochondrial oxidative phosphorylation, the process through which mitochondria convert nutrients into usable cellular energy. Changes in inorganic phosphate can provide clues about the balance between energy production and consumption, while alterations in phosphodiesters may reflect the breakdown or remodeling of cell membranes. Phosphomonoesters, by contrast, are often linked to membrane synthesis and cellular growth. Taken together, these chemical signals can offer a more detailed view of neuronal stress than a standard MRI, which mainly reveals anatomy. The reported regional pattern therefore raises the possibility that metabolic imaging could identify the specific circuits under greatest pressure in MSA-C.
The findings may also help clarify why the disease does not affect every patient in exactly the same way. MSA-P and MSA-C share a common pathological background, but the distribution and severity of degeneration differ between them. If the cerebellar subtype consistently produces a characteristic phosphorus-metabolite profile, 31P-MRS could eventually support the clinical distinction between the two forms. That would be especially useful during the early phase of illness, when symptoms may be incomplete, mixed or difficult to separate from Parkinson’s disease, hereditary ataxias and other neurodegenerative conditions. The technique would not necessarily replace neurological examination, structural MRI or genetic testing, but it could add a functional layer that shows how well vulnerable tissue is managing its energy demands.
The study also carries implications for treatment research. Multiple system atrophy currently has no proven disease-modifying therapy, and clinical trials are complicated by the disorder’s rapid progression and biological diversity. A regional metabolic marker could help researchers identify participants with comparable disease biology, track changes over time and test whether an experimental therapy protects energy metabolism in the cerebellum. If a treatment restores or stabilizes high-energy phosphorus metabolites, that effect might provide an early signal of biological activity before changes in walking, speech or coordination become measurable. At the same time, the researchers’ observation should not be interpreted as proof that metabolic dysfunction is the sole cause of MSA-C. Energy failure may be a driver of degeneration, a consequence of damaged cells or part of a self-reinforcing cycle involving alpha-synuclein, inflammation, mitochondrial stress and impaired cellular waste disposal.
For patients and families, the most immediate importance of the research is that it moves multiple system atrophy closer to being understood as a biologically diverse disease rather than a single uniform condition. The reported chemical fingerprint does not yet constitute a routine diagnostic test, and further studies will be needed to determine how reliably it separates MSA-C from other ataxias, how early the changes appear and whether they predict symptom progression. Researchers will also need to establish how factors such as age, disease duration, medication, vascular health and technical differences between scanners influence phosphorus measurements. Even with these questions unresolved, the work highlights a promising direction: looking beyond the brain’s shape to measure the energetic state of its circuits. In a disorder where diagnosis remains difficult and therapeutic options are limited, that ability could eventually transform both clinical decision-making and the search for effective treatments.
Subject of Research: Regional brain-energy metabolism in the cerebellar subtype of multiple system atrophy (MSA-C), measured through high-energy phosphorus metabolites.
Article Title: Regional reduction of high-energy phosphorus metabolites characterizes the cerebellar subtype of multiple system atrophy.
Article References: Prasuhn, J., Bodemann, C., Ebeling, B. et al. Regional reduction of high-energy phosphorus metabolites characterizes the cerebellar subtype of multiple system atrophy. npj Parkinson’s Disease. 12, 199 (2026). https://doi.org/10.1038/s41531-026-01537-y
Image Credits: AI Generated
DOI: https://doi.org/10.1038/s41531-026-01537-y
Keywords: Multiple system atrophy, MSA-C, cerebellum, neurodegeneration, phosphorus magnetic resonance spectroscopy, brain metabolism, ATP, phosphocreatine, mitochondrial dysfunction, Parkinson’s disease.
