An autopsy case of amyotrophic lateral sclerosis with striatonigral and pallidoluysian degeneration and cat's-eye-shaped neuronal nuclear inclusions

We report the case of a Japanese woman with sporadic amyotrophic lateral sclerosis (ALS) of 28 months' duration who died at the age of 66 years. Postmortem examination revealed moderate loss of neurons and phosphorylated TDP-43 (p-TDP-43)-immunoreactive neuronal and glial cytoplasmic inclusions in the upper and lower motor neurons. Additionally, marked neuronal loss was observed in the neostriatum, globus pallidum, subthalamic nucleus, and substantia nigra. p-TDP-43-immunoreactive inclusions were frequently found in these areas. Neuronal loss and TDP-43 pathology in the motor, striatonigral, and pallidoluysian systems were predominant on the right side. Moreover, p-TDP-43-immunoreactive cat's-eye-shaped neuronal nuclear inclusions (NNIs) were observed in the affected lesions. NNIs in the striatonigral system were also positive for valosin-containing protein (VCP). We diagnosed the patient as having ALS with striatonigral and pallidoluysian degeneration. Patients with ALS rarely experience pallido-nigro-luysian degeneration. To our best knowledge, only one case of ALS combined with striatonigral and pallidoluysian degeneration has been reported. Neuronal loss in the striatonigral and/or pallidoluysian systems has also been reported in patients with ALS with multisystem degeneration accompanied by long-term use of an artificial respirator. Based on these findings, a possibility of an extremely rare subtype of ALS demonstrating selective loss of neurons in the striatonigral and pallidoluysian systems exists; another possibility is that this type could be an early stage or forme fruste of ALS with multisystem degeneration. Although VCP-positive cat's-eye-shaped NNIs have been reported in spinocerebellar ataxia type-2 cases, our case report presents VCP-positive NNIs in a patient with ALS for the first time.

Amyotrophic Lateral Sclerosis with Pallidonigroluysian Degeneration: A Clinicopathological Study

OBJECTIVE

The pallidonigroluysian (PNL) system, the primary component of corticosubcortical circuits, is generally spared in amyotrophic lateral sclerosis (ALS). We evaluated the clinicopathological features of an unusual form of ALS with PNL degeneration (PNLD) and assessed whether ALS with PNLD represents a distinct ALS subtype.

METHODS

From a cohort of 97 autopsied cases of sporadic ALS with phosphorylated 43kDa TAR DNA-binding protein (TDP-43) inclusions, we selected those with PNLD and analyzed their clinicopathological features.

RESULTS

Eleven cases (11%) that showed PNLD were divided into 2 subtypes depending on the lesion distribution: (1) extensive type (n = 6), showing widespread TDP-43 pathology and multisystem degeneration, both involving the PNL system; and (2) limited type (n = 5), showing selective PNL and motor system involvement, thus being unclassifiable in terms of Brettschneider's staging or Nishihira's typing of ALS. The limited type showed a younger age at onset and predominant PNLD that accounted for the early development of extrapyramidal signs. The limited type exhibited the heaviest pathology in the subthalamus and external globus pallidus, suggesting that TDP-43 inclusions propagated via indirect or hyperdirect pathways, unlike ALS without PNLD, where the direct pathway is considered to convey TDP-43 aggregates from the cerebral cortex to the substantia nigra.

INTERPRETATION

The PNL system can be involved in the disease process of ALS, either nonselectively as part of multisystem degeneration, or selectively. ALS with selective involvement of the PNL and motor systems exhibits unique clinicopathological features and TDP-43 propagation routes, thus representing a distinct subtype of ALS. ANN NEUROL 2020;87:302-312.

Pathological and immunoblot analysis of phosphorylated TDP-43 in sporadic amyotrophic lateral sclerosis with pallido-nigro-luysian degeneration

Transactivation response DNA-binding protein 43 kDa (TDP-43) is a key protein of sporadic amyotrophic lateral sclerosis (ALS), and phosphorylated form of TDP-43 (p-TDP-43) is a major pathological protein that accumulates in sporadic ALS. p-TDP-43 is found not only in primary motor neurons, but often propagates to non-motor systems as well. However, pallido-nigro-luysian (PNL) degeneration (PNLD) is rarely associated with ALS. We describe here a 68-year-old ALS patient presenting severe PNLD. He had difficulty walking due to poor movement of his right leg, and was diagnosed as having Parkinson's disease because of akinesia. About 2 years after onset, weakness of his left hand and leg led to a diagnosis of ALS. Tube feeding and non-invasive positive-pressure ventilation were initiated. He died of respiratory failure at the age of 71. There was no family history of either neurological disorders or dementia. Neuropathological examination revealed severe loss of neurons and gliosis in the PNL system in addition to the upper and lower motor neuron system. p-TDP-43 pathology was widespread in the PNL and motor neuron systems and also in the amygdala and hippocampus where no significant gliosis or neuronal loss was detected. Synuclein pathology was not observed in the investigated areas. Immunoblot analysis of p-TDP-43 C-terminal fragments showed a type B band pattern consistent with sporadic ALS. This is the first case of ALS with PNLD, in which p-TDP-43 distribution was widespread in the hippocampal formation (Nishihira type 2 and Brettschneider stage 4), and the type B immunoblot pattern was confirmed. Our case indicated that the PNL system can be involved in the disease process in sporadic ALS cases, although rarely. We also reviewed previous autopsy cases of ALS with PNLD to clarify the clinicopathological features.

Pathological and Clinical Spectrum of Progressive Supranuclear Palsy: With Special Reference to Astrocytic Tau Pathology

Progressive supranuclear palsy (PSP) is a four-repeat tauopathy with tau-positive, argyrophilic tuft-shaped astrocytes (TAs). We performed a pathological and clinical investigation in 40 consecutive autopsied Japanese patients with pathological diagnoses of PSP or PSP-like disease. Unequivocal TAs were present in 22 cases, all of which were confirmed to be PSP. Such TAs were hardly detected in the other 18 cases, which instead exhibited tau-positive, argyrophilic astrocytes, appearing as comparatively small clusters with central nuclei of irregularly shaped, coarse structures (equivocal TAs). Cluster analysis of the distribution pattern of tau-related pathology for these 18 cases identified two subgroups, pallido-nigro-luysian atrophy (PNLA) Type 1 (n = 9) and Type 2 (n = 9), the former being distinguished from the latter by the presence of tau-related lesions in the motor cortex, pontine nucleus and cerebellar dentate nucleus in addition to the severely affected PNL system. The duration from symptom onset until becoming wheelchair-bound was significantly longer in PNLA Type 1. Immunoblotting of samples from the three disease conditions revealed band patterns of low-molecular-mass tau fragments at ∼35 kDa. These findings shed further light on the wide pathological and clinical spectrum of four-repeat tauopathy, representing PSP in the broad sense rather than classical PSP.

Ventilatory control in ALS

Amyotrophic lateral sclerosis (ALS) is a fatal, progressive neurodegenerative disease. ALS selectively causes degeneration in upper and lower (spinal) motor neurons, leading to muscle weakness, paralysis and death by ventilatory failure. Although ventilatory failure is generally the cause of death in ALS, little is known concerning the impact of this disorder on respiratory motor neurons, the consequences of respiratory motor neuron cell death, or the ability of the respiratory control system to "fight back" via mechanisms of compensatory respiratory plasticity. Here we review known effects of ALS on breathing, including possible effects on rhythm generation, respiratory motor neurons, and their target organs: the respiratory muscles. We consider evidence for spontaneous compensatory plasticity, preserving breathing well into disease progression despite dramatic loss of spinal respiratory motor neurons. Finally, we review current and potential therapeutic approaches directed toward preserving the capacity to breathe in ALS patients.

Clinicopathological review of pallidonigroluysian atrophy

Pallidonigroluysian atrophy is a rare neurodegenerative disease characterized by degeneration of the globus pallidus, substantia nigra, and subthalamic nucleus. Few studies have comprehensively documented the clinical and pathological features of pallidonigroluysian atrophy. A systematic review of all published cases of pallidonigroluysian atrophy in English since 1970 was performed. We also report a new case of pallidonigroluysian atrophy. Twenty-five cases of pathologically proven pallidonigroluysian atrophy were reviewed, 24 from the literature and 1 of our own. Average age of onset was 54.3 ± 14.3 years, and average duration of disease was 7.9 ± 5.8 years. The most common first symptom was gait or balance disturbance. Patients had a diversity of movement disorders, including chorea in 5 cases (20%). Nine cases (36%) had coexistent motor neuron disease. Almost all cases had gliosis, and many cases had iron-positive pigments in the pallidonigroluysian system. Tauopathy was absent to rare in this region. Widespread tau-negative, p62-positive glial inclusions, described in 1 previous case, were also present in our patient. As pallidonigroluysian atrophy has a diversity of clinical presentations, it is best defined neuropathologically. The relative lack of tauopathy and the presence of p62-positive glial inclusions or iron-positive pigments in the pallidonigroluysian region may help to distinguish pallidonigroluysian atrophy from similar disease entities.

Proportional neuronal loss between the primary motor and sensory cortex in amyotrophic lateral sclerosis

The number of neurons in the primary motor cortex (MI) and the primary somatosensory cortex (SI) were estimated in the same locations of brains from sporadic amyotrophic lateral sclerosis (ALS) cases and controls. The number of MI and SI neurons and Betz cells were significantly decreased in the ALS cases as compared to the controls. The number of neurons in MI and SI was independent of age at death or duration of disease. Moreover, the number of neurons in MI and SI was significantly correlated, suggesting that the neurons in both sites might be interdependent and might decrease proportionally.

Sporadic amyotrophic lateral sclerosis with pallido-nigro-luysian degeneration: a TDP-43 immunohistochemical study

Recently, Nishihira et al. demonstrated the presence of two types of TDP-43 pathology in sporadic amyotrophic lateral sclerosis (ALS) (Acta Neuropathol 2008; 116: 169-182). Type 1 represents the TDP-43 distribution pattern observed in classic ALS, whereas type 2 shows the presence of TDP-43 inclusions in the frontotemporal cortex, hippocampal formation, neostriatum and substantia nigra and is significantly associated with dementia. However, ALS with pallido-nigro-luysian degeneration (PNLD) is very rare. We recently encountered a case of ALS with PNLD of 9 years duration, in which the patient received artificial respiratory support for 6 years. In our case, neuronal loss and TDP-43-positive neuronal cytoplasmic inclusions were found in the globus pallidus, substantia nigra and subthalamic nucleus. Neither neuronal loss nor TDP-43-immunoreactive inclusions were found in the frontotemporal cortex and hippocampus. These findings suggest that the pallido-nigro-luysian system is also involved in the disease process of ALS and that ALS with PNLD is different from ALS with dementia based on the distribution pattern of neuronal loss and TDP-43 accumulation.