ABSTRACT
Perry disease (Perry syndrome) is a rare, rapidly progressive, autosomal dominant neurodegenerative disease characterized by parkinsonism, depression/apathy, weight loss, and respiratory symptoms including central hypoventilation. It is caused by missense mutations (e.g. p.G71A) in the DCTN1 gene. We previously generated transgenic mice that expressed human DCTN1G71A mutant protein under the control of Thy1 promoter. These mice exhibited apathy-like behavior and parkinsonism. However, it is possible that this phenotype was due to a gene-dosage imbalance or transgene insertion position. To circumvent these potential caveats, we have generated a knock-in mouse model carrying a p.G71A mutation in Dctn1. Heterozygous Dctn1G71A and wild-type littermates were subjected to a battery of behavioral analyses. Furthermore, immunohistochemistry for tyrosine hydroxylase (TH) was performed on brain sections of these mice, and TH signal intensity in substantia nigral neurons was quantified. Dctn1G71A mice were immobile for longer than wild-type mice of the same age and sex in the tail-suspension test, revealing depressive characteristics. In addition, the beam-walking test and pole test detected motor deficits in Dctn1G71A female mice. Finally, immunostaining revealed a decrease in TH immunoreactivity in neurons of the substantia nigra in the Dctn1G71A mice. Collectively, heterozygous Dctn1G71A mice showed depression-like behavior, motor deficits, and a functional reduction in substantia nigral neurons, as judged by TH immunostaining, thereby exhibiting multiple features of Perry disease. Hence, this mouse model will be useful in elucidating pathological mechanisms of Perry disease and for developing novel therapeutic strategies against it.
Subject(s)
Dynactin Complex/genetics , Hypoventilation/psychology , Parkinsonian Disorders/psychology , Animals , Behavior Observation Techniques , Behavior, Animal , Depression/genetics , Depression/pathology , Depression/psychology , Disease Models, Animal , Female , Gene Knock-In Techniques , Heterozygote , Humans , Hypoventilation/genetics , Hypoventilation/pathology , Male , Mice , Mice, Transgenic , Mutation , Neurons/pathology , Parkinsonian Disorders/genetics , Parkinsonian Disorders/pathology , Substantia Nigra/pathology , Tyrosine 3-Monooxygenase/analysis , Tyrosine 3-Monooxygenase/metabolismABSTRACT
A 57-year-old woman was referred to our hospital because of descending colon cancer with multiple liver metastases. Abdominal magneticresonanc e imaging (MRI) revealed 13 liver metastases across the lobes. We started combination che- motherapy with capecitabine/oxaliplatin (CapeOX) and bevacizumab. After 9 courses of the treatment, the number and size of the liver metastases were remarkably reduced on MRI. Left colectomy and partial hepatectomy were performed. Histopathological examination revealed no residual cancer cells in the colon but revealed a few cancer cells in 4 of 7 resected liver specimens. At 11 postoperative months, 1 liver metastasis reappeared, for which we performed laparoscopy-assisted partial hepatectomy. At 21 months after the second operation, the patient was well without any signs of recurrence. Thus, the combination chemotherapy with CapeOX and bevacizumab allowed for the successful resection of the tumor and metastasis in our patient who initially had unresectable colon cancer and multiple liver metastases.
