Anticholinergic Burden, Polypharmacy, and Cognition in Parkinson's Disease Patients with Mild Cognitive Impairment: A Cross-Sectional Observational Study.

INTRODUCTION: Anticholinergic burden may be an important risk factor for the cognitive impairment. Especially in polypharmacy, even drugs with low anticholinergic effects may contribute to a significant anticholinergic burden. The drugs with anticholinergic effects are used in treatment of motor and nonmotor symptoms of Parkinson's disease (PD). Therefore, it is important to screen for polypharmacy and anticholinergic burden in PD patients with mild cognitive impairment (MCI). METHODS: This cross-sectional study was conducted with 58 patients with PD. PD-MCI was diagnosed according to MDS Level 2 Comprehensive Assessment. Cognitive performance (attention - working memory, executive functions, language, memory, and visuospatial functions) of patients was evaluated. The anticholinergic burden was scored by Anticholinergic Cognitive Burden (ACB) Scale, Anticholinergic Risk Scale (ARS), and Anticholinergic Drug Scale (ADS). RESULTS: There was no significant difference in anticholinergic burden between PD-MCI and PD-normal cognition. A significant concordance was observed between ACB, ARS, and ADS scores (p < 0.001; Kendall's W = 0.653). While the variable predicting anticholinergic burden was the total number of drugs for ACB and ADS scales, it was the number of antiparkinson drugs for ARS scale. CONCLUSION: Patients with PD are at high risk for polypharmacy and anticholinergic burden. Anticholinergic burden should be considered in the selection of drugs, especially for comorbidities in patients with PD. No significant correlation was found between the cognition and anticholinergic burden in patients with PD-MCI. Although the risk scores of antiparkinson and other drugs were different among the 3 scales, significant concordance was observed between scales.

Genotype-Phenotype correlations of SCARB2 associated clinical presentation: a case report and in-depth literature review.

BACKGROUND: Biallelic pathogenic variants in the SCARB2 gene have been associated with action myoclonus-renal failure (AMRF) syndrome. Even though SCARB2 associated phenotype has been reported to include typical neurological characteristics, depending on the localization and the feature of the pathogenic variants, clinical course and the presentations have been shown to differ. CASE PRESENTATION: Whole exome sequencing (WES) analysis revealed a homozygous truncating variant (p.N45MfsX88) in SCARB2 gene in the index case, and subsequent sanger sequencing analysis validated the variant in all affected family members from a Turkish family with the clinical characteristics associated with AMRF and related disorders. Intrafamilial clinical heterogeneity with common features including dysarthria, tremor and proteinuria, and distinct features such as peripheral neuropathy (PNP), myoclonus and seizures between the affected cases, was observed in the family. In-depth literature review enabled the detailed investigation of the reported variants associated with AMRF and suggested that while the type of the variant did not have a major impact on the course of the clinical characteristics, only the C terminal localization of the pathogenic variant significantly affected the clinical presentation, particularly the age at onset (AO) of the disease. CONCLUSIONS: In this study we showed that biallelic SCARB2 pathogenic variants might cause a spectrum of common and distinct features associated with AMRF. Of those features while the common features include myoclonus (100%), ataxia (96%), tonic clonic seizures (82%), dysarthria (68%), tremor (65%), and renal impairment (62%), the uncommon features involve PNP (17%), hearing loss (6.8%), and cognitive impairment (13.7%). AO has been found to be significantly higher in the carriers of the p.G462DfsX34 pathogenic variant. SCARB2 pathogenic variants have not been only implicated in AMRF but also in the pathogenesis of Parkinson's disease (PD) and Gaucher disease (GD), suggesting the importance of genetic and functional studies in the clinical and the diagnostic settings. Given the proven role of SCARB2 gene in the pathogenesis of AMRF, PD and GD with a wide spectrum of clinical symptoms, investigation of the possible modifiers, such as progranulin and HSP7, has a great importance.

Characterization of Recessive Parkinson Disease in a Large Multicenter Study.

Studies of the phenotype and population distribution of rare genetic forms of parkinsonism are required, now that gene-targeting approaches for Parkinson disease have reached the clinical trial stage. We evaluated the frequencies of PRKN, PINK1, and DJ-1 mutations in a cohort of 1,587 cases. Mutations were found in 14.1% of patients; 27.6% were familial and 8% were isolated. PRKN was the gene most frequently mutated in Caucasians, whereas PINK1 mutations predominated in Arab-Berber individuals. Patients with PRKN mutations had an earlier age at onset, and less asymmetry, levodopa-induced motor complications, dysautonomia, and dementia than those without mutations. ANN NEUROL 2020;88:843-850.

TREM2 variants as a possible cause of frontotemporal dementia with distinct neuroimaging features.

BACKGROUND AND PURPOSE: Nasu-Hakola disease (NHD) is a rare, autosomal recessive disorder characterized by skeletal and neurological symptoms. Behavioral symptoms with cognitive impairment may mimic the behavioral variant of frontotemporal dementia (bvFTD) and other early-onset dementias. Our patients were analyzed and the literature was reviewed to delineate neurological and neuroimaging findings suggestive of NHD. METHOD: Fourteen patients carrying a pathogenic mutation in the TREM2 gene were found in our database. Demographic, clinical, laboratory and radiological data were retrieved and analyzed. RESULTS: The presenting clinical picture was behavioral changes with cognitive decline resembling bvFTD in all patients. The mean age was 37.1 ± 4.97 years and the mean duration of the disease was 8.9 ± 3.51 years. Only two patients had typical bone cysts. Seven patients had bilateral calcification of the basal ganglia in computed tomography of the brain. Magnetic resonance imaging of the brain revealed severe atrophy of the corpus callosum, enlargement of the ventricles, atrophy of the caudate nuclei and periventricular white matter changes in all patients. Symmetrical global atrophy of the brain mainly affecting frontoparietal and lateral temporal regions were observed in all cases, and 13 patients had atrophy of the hippocampus. Cerebrospinal fluid examination of 10 patients showed elevated protein levels in six and the presence of oligoclonal bands in four patients. CONCLUSION: A combination of white matter changes, enlarged ventricles, atrophy of the caudate nuclei and thinning of the corpus callosum in magnetic resonance imaging strongly suggests NHD in patients with FTD syndrome. Molecular genetic analysis should be performed in suspected cases, and families should receive genetic counseling.

Neurological features and outcomes of Wilson's disease: a single-center experience.

Wilson's disease (WD) is an autosomal recessive genetic disorder of copper metabolism, and WD patients can present with neurologic symptoms. We aimed to report the general characteristics and prognosis of a Turkish series of WD patients with neurological manifestations. A total of 12,352 patients were screened from the patient database, and 53 WD patients were included. Patients were classified based on the predominant neurological syndrome type including tremor, dystonia, parkinsonism, or discrete neurological signs and were classified as having "good outcome," "stable," and "poor outcome" according to their treatment response. There were 32 male and 21 female patients, aged 20-66 years. The mean follow-up was 11.3 ± 4.56 years. Sixty-two percent of patients presented predominantly with neurological symptoms. Neurological WD diagnosis was established after a mean time delay of 2.3 years from the WD diagnosis. The most common neurological manifestation was dystonia, followed by tremor and parkinsonism. Fifteen patients had a family history of WD. Consanguinity was present in 20 patients. Patients were treated with D-penicillamine, trientine, zinc salts, or their combinations. Besides the main treatments, 41 patients were on symptomatic treatment for neurologic symptoms. Thirty-six patients had a "good outcome," five patients were stable, and six patients had "poor outcome." Post-chelation neurological worsening was observed in 11 patients. WD should be considered in differential diagnosis in any patient with unexplained neurologic symptoms. Early diagnosis is important, and appropriate treatment should be promptly initiated to prevent progressive and irreversible damage, with good prognosis and stable disease in the majority of the patients with treatment compliance.

Do Alzheimer's Disease Patients Appear Younger than Their Real Age?

INTRODUCTION: The most prominent risk factor of Alzheimer's disease (AD) is aging. Aging also influences the physical appearance. Our clinical experience suggests that patients with AD may appear younger than their actual age. Based on this empirical observation, we set forth to test the hypothesis with human and computer-based estimation systems. METHOD: We compared 50 early-stage AD patients with 50 age and sex-matched controls. Facial images of all subjects were recorded using a video camera with high resolution, frontal view, and clear lighting. Subjects were recorded during natural conversations while performing Mini-Mental State Examination, including spontaneous smiles in addition to static images. The images were used for age estimation by 2 methods: (1) computer-based age estimation; (2) human-based age estimation. Computer-based system used a state-of-the-art deep convolutional neural network classifier to process the facial images contained in a single-video session and performed frame-based age estimation. Individuals who estimated the age by visual inspection of video sequences were chosen following a pilot selection phase. The mean error (ME) of estimations was the main end point of this study. RESULTS: There was no statistically significant difference between the ME scores for AD patients and healthy controls (p = 0.33); however, the difference was in favor of younger estimation of the AD group. The average ME score for AD patients was lower than that for healthy controls in computer-based estimation system, indicating that AD patients were on average estimated to be younger than their actual age as compared to controls. This difference was statistically significant (p = 0.007). CONCLUSION: There was a tendency for humans to estimate AD patients younger, and computer-based estimations showed that AD patients were estimated to be younger than their real age as compared to controls. The underlying mechanisms for this observation are unclear.

Functional neural substrates of football fanaticism: Different pattern of brain responses and connectivity in fanatics.

AIM: Sports activities provide social interaction for humans. Commitment to a given team is a salient feature of being a sports fan and becomes a prominent part of self-identification for fanatics. Emotion, subjective hedonic experience, and non-romantic love are related to fan behaviors. Few studies have evaluated the neural basis of sports fanaticism. METHODS: Thirty men, including 16 football fanatics and 14 non-fanatics, with a mean age of 27.4 ± 6.4 years (range, 20-48 years) were enrolled. Subjects underwent functional MRI while watching a set of goals scored by favorite, rival, and neutral teams. RESULTS: The analysis of variance in a general linear model revealed a significant Group × Condition interaction effect in the bilateral dorsal anterior cingulate cortex (dACC) that was more prominent in the left hemisphere. In the post-hoc comparisons, fanatics showed increased activation in bilateral dACC, supplementary motor area, superior frontal cortex, right dorsolateral prefrontal cortex, and right insula for Favorite > Neutral contrast and an increased activation in bilateral dACC and supplementary motor area for Rival > Neutral contrast. Seed-based connectivity analyses using the areas with significant activation differences revealed increased connectivity between dACC and several regions, including the left posterior lateral temporal area, insula, bilateral medial temporal area, and medial superior frontal area as well as the basal ganglia in fanatics compared to non-fanatics. CONCLUSION: Our results suggest that football fanatics exhibit a different brain activation and connectivity pattern from non-fanatics, both under favorable and unfavorable conditions. This brain activity and connectivity pattern under emotionally laden conditions may represent higher responses to rewards, higher emotional valence attribution, and stronger motivational state of football fanatics, which might underlie their unusual behavioral responses.

Potential Protective Role of SDF-1 and CXCR4 Gene Variants in the Development of Dementia.

BACKGROUND: The aim of this study was to evaluate the role of polymorphisms of stromal cell-derived factor-1 (SDF-1) and chemokine receptor-4 (CXCR4) genes in dementia susceptibility in a Turkish population. SUBJECTS AND METHODS: The study group included 61 dementia patients, while the control group comprised 82 healthy individuals. Gene polymorphisms of SDF-1 3'A G801A (rs1801157) and CXCR4 C138T (rs2228014) were genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis. RESULTS: A significantly reduced risk for developing dementia was found for the group bearing an A allele for SDF-1 3'A polymorphism (p=0.009; χ2=6.812; OR=0.626; 95%CI= 0.429-0.913). The frequency of the CXCR4 TT and TC genotype was significantly lower in patients with dementia compared to controls (p=0.028; χ2=5.583; OR=0.215; 95%CI=0.05-0.914); (p=0.027; χ2=4.919; OR=0.484; 95% CI=0.246-0.955). Additionally, combined genotype analysis showed that the frequency of SDF1 GA-CXCR4 CC was significantly lower in patients with dementia in comparison with those of controls (p=0.049; OR=0.560; 95% CI= 0.307±1.020). CONCLUSIONS: Our study provides new evidence that SDF1 A and CXCR4 T alleles may be associated with a decreased dementia risk. The present study is important because to our knowledge, it is the first one to be conducted in a Turkish population to date, but we believe that more patients and controls are needed to obtain statistically significant results.

Loss of VPS13C Function in Autosomal-Recessive Parkinsonism Causes Mitochondrial Dysfunction and Increases PINK1/Parkin-Dependent Mitophagy.

Autosomal-recessive early-onset parkinsonism is clinically and genetically heterogeneous. The genetic causes of approximately 50% of autosomal-recessive early-onset forms of Parkinson disease (PD) remain to be elucidated. Homozygozity mapping and exome sequencing in 62 isolated individuals with early-onset parkinsonism and confirmed consanguinity followed by data mining in the exomes of 1,348 PD-affected individuals identified, in three isolated subjects, homozygous or compound heterozygous truncating mutations in vacuolar protein sorting 13C (VPS13C). VPS13C mutations are associated with a distinct form of early-onset parkinsonism characterized by rapid and severe disease progression and early cognitive decline; the pathological features were striking and reminiscent of diffuse Lewy body disease. In cell models, VPS13C partly localized to the outer membrane of mitochondria. Silencing of VPS13C was associated with lower mitochondrial membrane potential, mitochondrial fragmentation, increased respiration rates, exacerbated PINK1/Parkin-dependent mitophagy, and transcriptional upregulation of PARK2 in response to mitochondrial damage. This work suggests that loss of function of VPS13C is a cause of autosomal-recessive early-onset parkinsonism with a distinctive phenotype of rapid and severe progression.

Parkinson's Disease Dementia and Lewy Body Disease.

Dementia with Lewy bodies (DLB) and Parkinson's disease dementia (PD-D) are Lewy body-related neurodegenerative disorders sharing common clinical and neuropathological findings. The clinical features of both conditions include cognitive impairment, behavioral symptoms, autonomic dysfunction, sleep disorders, and parkinsonism. The cognitive profile of both disorders is characterized by particularly severe deficits in executive and visuospatial functions as well as attention. Clinical differentiation between DLB and PD-D is based on an arbitrary distinction between the time of onset of parkinsonism and cognitive symptoms; extrapyramidal symptoms precede dementia in PD-D, whereas it coincides with or follows dementia within 1 year in DLB. When the clinical picture is fully developed, DLB and PD-D are practically indistinguishable. Although the diagnosis is basically clinical, structural and functional neuroimaging as well as cerebrospinal fluid biomarkers may help the clinician in the diagnosis. Placebo-controlled randomized trials of the cholinesterase inhibitors have shown modest but significant benefits in cognition, global function, and neuropsychiatric symptoms in both disorders. Behavioral symptoms such as hallucinations and delusions should be treated with caution with antipsychotics, as they have the potential to worsen motor and cognitive symptoms.

Patients with Lately Diagnosed Cerebrotendinous Xanthomatosis.

OBJECTIVES: Cerebrotendinous xanthomatosis (CTX) is a rare autosomal recessive inborn lipid storage disorder due to various pathogenic mutations in the CYP27A1 gene. Although the symptoms begin commonly in infancy, CTX diagnosis is often delayed. In this study, we report 7 Turkish CTX patients who had a delayed diagnosis despite early clinical signs and belonged to 6 unrelated families. METHODS: We have retrospectively evaluated clinical, laboratory, imaging, and genetic findings of CTX patients, which were collected from 2 centers specialized in movement disorders: the Department of Neurology, Faculty of Medicine, Istanbul University, and the Department of Neurology, Faculty of Medicine, Mersin University. RESULTS: All patients were diagnosed with CTX after neurological symptom development, and their mean age at diagnosis was 38.7 ± 9.6 years, despite a mean onset age of 12.4 ± 10.6 years. The mean follow-up period was 28 months (range: 3-60 months). The most common initial clinical abnormalities in our cohort were unexplained chronic diarrhea (42%), febrile convulsion (42%), juvenile cataract (85%), childhood depression and autism (14%), parkinsonism (14%), and intellectual disability (100%). The most prominent neurological findings were the pyramidal-cerebellar syndrome (85%) and extrapyramidal signs (42%). All patients were genetically confirmed. Serum cholestanol levels were elevated in all patients and decreased after chenodeoxycholic acid (CDCA) treatment in 6 patients. CONCLUSION: This cohort is the largest CTX case series in Turkey. All cases showed improvement in gastrointestinal symptoms as a response to CDCA treatment and stabilization on neurological symptoms, i.e., no further progression of neurological abnormalities were noted during this treatment. Therefore, early diagnosis and treatment is crucial in preventing clinical deterioration.

Cognitive and anatomical correlates of anosognosia in amnestic mild cognitive impairment and early-stage Alzheimer's disease.

BACKGROUND: Anosognosia is a common feature in Alzheimer's disease (AD). The brain substrates of anosognosia are not fully understood, and less is known about the cognitive substrates of anosognosia in prodromal and early stages of AD. METHODS: Fourty-seven patients with amnestic-type mild cognitive impairment (aMCI) (n = 26) and early-stage AD (n = 21) were included, and Clinical Insight Rating Scale and Anosognosia Questionnaire for Dementia (AQ-D) were used to assess anosognosia. A detailed neuropsychological battery was administered; each patient underwent a structural magnetic resonance imaging (MRI). Correlation between anosognosia and performance in individual cognitive domains as well as correlation between anosognosia and cortical thickness values in regions of interest were assessed. RESULTS: Performance of the anosognosic patients in Digit Ordering Test (DOT), Digit Span Backwards, and Clock Drawing Test (CDT) was significantly worse compared to non-anosognosic patients in the total study population and in the aMCI subgroup but not in AD group. AQ-D scores negatively correlated with Mini-Mental State Examination (MMSE), California Verbal Learning Test (CVLT), Digit Span Backwards and CDT scores in total group and MMSE, CVLT, DOT, and Digit Span Backwards scores in the aMCI group. No significant correlations were found between cortical thickness measurements and AQ-D scores in any of the patient populations. CONCLUSIONS: Anosognosia was associated with episodic memory, working memory, and executive functions in the total population and aMCI group, but no association was found in early-stage AD patients. Anosognosia in the early stages of AD may be related with non-structural changes such as hypoconnectivity rather than structural changes.

The Association Between Clusterin and APOE Polymorphisms and Late-Onset Alzheimer Disease in a Turkish Cohort.

Previous studies have demonstrated that clusterin (CLU), which is also known as apolipoprotein J, is involved in the pathogenesis of Alzheimer disease (AD). In this study, we investigated the association between rs2279590, rs11136000, and rs9331888 single-nucleotide polymorphisms (SNPs) in CLU and apolipoprotein E (APOE) genotypes in a cohort of Turkish patients with late-onset AD (LOAD). There were 183 patients with LOAD and 154 healthy controls included in the study. The CLU and APOE polymorphisms were genotyped using the LightSNiP assay. The "GG" genotype of rs9331888 was significantly more frequent in patients with LOAD. The "CC" genotype of the SNP was significantly more frequent in controls. The rs9331888 "GG" genotype in patients and the "CC" genotype in controls were significantly higher in non-∊4 allele carriers of APOE The haplotype analysis showed the CLU "GCG" haplotype was a risk haplotype. Our findings indicate the rs9331888 SNP of CLU is associated with LOAD independent of APOE.

Adult-onset phenylketonuria with rapidly progressive dementia and parkinsonism.

Phenylketonuria (PKU) is an autosomal recessive metabolic disorder due to mutations in the phenylalanine hydroxylase (PAH) gene, which converts phenylalanine (PHE) to tyrosine. Although it is principally a childhood disorder, in rare cases, the first signs of PKU may develop in late adulthood resembling common neurological diseases. Here we report a 59-year-old, previously normal functioning man who was admitted with blurred vision, cognitive problems, and gait difficulty that began 8 months before. He had brisk reflexes and left side dominant parkinsonism. His Mini-Mental State Examination (MMSE) score was 25/30, and neuropsychological evaluation revealed a dysexecutive syndrome with simultanagnosia and constructional apraxia. His Clinical Dementia Rating score (CDR) was 1. Cranial MRI revealed bilateral diffuse hyperintense lesions in parietal and occipital white matter in T2, fluid-attenuated inversion recovery, and diffusion weighted images. Diagnostic workup for rapidly progressive dementias was all normal except PHE level which was found to be highly elevated (1075 µmol/L, normal 39-240 µmol/L) with normal tyrosine level (61.20 µmol/L, normal 35-100 µmol/L). Three months after PHE-restricted diet, his cognitive impairment and signs of parkinsonism significantly improved, with MRI scan unchanged. This case demonstrates that late-onset PKU is a rare, treatable cause of rapidly progressive dementia and parkinsonism with certain constellations such as consanguinity and white matter abnormalities (WMAs) in imaging.

A new F-box protein 7 gene mutation causing typical Parkinson's disease.

BACKGROUND: Recessive mutations in the F-box protein 7 gene (FBXO7; PARK15) have been identified as a cause of the parkinsonian-pyramidal syndrome. Here, we report clinical and genetic findings in a Turkish family with novel FBXO7 mutations. METHODS: Whole exome and targeted Sanger sequencing were performed for genetic analysis in a family with two members affected by Parkinson's disease (PD). All family members underwent detailed clinical, mental, and neurological examination. RESULTS: The new p.L34R (c.101 T>G) FBXO7 mutation was detected in a homozygous state in two Turkish sibs with typical levodopa-responsive PD. CONCLUSION: This is the first time a FBXO7 mutation has been identified that causes a phenotype compatible with typical idiopathic PD and presents with some of its common nonmotor features, such as rapid eye movement sleep behavior disorder, depression, and anxiety.

Cognitive impairment and dementia in Parkinson's disease: practical issues and management.

Cognitive impairment and dementia pose particular challenges in the management of patients with Parkinson's disease (PD). Decision-making capacity can render patients vulnerable in a way that requires careful ethical considerations by clinicians with respect to medical decision making, research participation, and public safety. Clinicians should discuss how future decisions will be made as early in the disease course as possible. Because of cognitive, visual, and motor impairments, PD may be associated with unsafe driving, leading to early driving cessation in many. DBS of the STN and, to a lesser degree, globus pallidus interna (GPi) has consistently been associated with decreased verbal fluency, but significant global cognitive decline is usually not observed in patients who undergo rigorous selection. There are some observations suggesting lesser cognitive decline in GPi DBS than STN DBS, but further research is required. Management of PD dementia (PDD) patients involves both pharmacological and nonpharmacological measures. Patients with PDD should be offered treatment with a cholinesterase inhibitor taking into account expected benefits and potential risks. Treatment with neuroleptics may be necessary to treat psychosis; classical neuroleptics, as well as risperidone and olanzapine, should be avoided. Quetiapine might be considered first-line treatment because it does not need special monitoring, although the strongest evidence for efficacy exists for clozapine. Evidence from randomized, controlled studies in the PDD population is lacking; selective serotonin reuptake inhibitors or serotonin-norepinephrine reuptake inhibitors may be used to treat depressive features. Clonazepam or melatonin may be useful in the treatment of rapid eye movement behavior disorder.

Clinical spectrum of human STAR variants and their genotype-phenotype correlation.

Biallelic variants of steroidogenic acute regulatory protein (STAR/STARD1) may cause primary adrenal insufficiency and 46,XY disorder of sex development. STAR plays a pivotal role in transporting cholesterol into mitochondria where cholesterol serves as essential substrate for initiating steroid biosynthesis by its conversion to pregnenolone. Generally, loss-of-function mutations of STAR cause the classic form of lipoid Congenital Adrenal Hyperplasia (LCAH) where steroidogenesis of the adrenal cortex and the gonads is severely affected. By contrast, partial activity of STAR causes a less severe phenotype, the non-classic LCAH, which is characterized by later onset and initial manifestation with isolated adrenal insufficiency only. Disease causing STAR variants are very rare. Numerous variants of all types have been described worldwide. Prevailing variants have been reported from Japan and Korea and in some population clusters where STAR is more common. Genotype-phenotype correlation is pretty good for STAR variants. While the exact mechanisms of cholesterol transport into mitochondria for steroidogenesis are still under investigation, the important role of STAR in this process is evident by inactivating STAR variants causing LCAH. The mechanism of disease with STAR deficiency is best described by a two hit model: The first hit relates to impaired cholesterol import into mitochondria and thus lack of substrate for all steroid hormone biosynthesis. The second hit then relates to massive cytoplasmic lipid overload (evidenced by typically enlarged and fatty adrenal glands) leading to cell death and organ destruction. This review summarizes phenotype and genotype characteristics of human STAR variants found through the ClinVar database.

Adrenal Abcg1 Controls Cholesterol Flux and Steroidogenesis.

Cholesterol is the precursor of all steroids, but how cholesterol flux is controlled in steroidogenic tissues is poorly understood. The cholesterol exporter ABCG1 is an essential component of the reverse cholesterol pathway and its global inactivation results in neutral lipid redistribution to tissue macrophages. The function of ABCG1 in steroidogenic tissues, however, has not been explored. To model this, we inactivated Abcg1 in the mouse adrenal cortex, which led to an adrenal-specific increase in transcripts involved in cholesterol uptake and de novo synthesis. Abcg1 inactivation did not affect adrenal cholesterol content, zonation, or serum lipid profile. Instead, we observed a moderate increase in corticosterone production that was not recapitulated by the inactivation of the functionally similar cholesterol exporter Abca1. Altogether, our data imply that Abcg1 controls cholesterol uptake and biosynthesis and regulates glucocorticoid production in the adrenal cortex, introducing the possibility that ABCG1 variants may account for physiological or subclinical variation in stress response.

Mitochondrial dysfunction results in enhanced adrenal androgen production in H295R cells.

The role of mitochondria in steroidogenesis is well established. However, the specific effects of mitochondrial dysfunction on androgen synthesis are not fully understood. In this study, we investigate the effects of various mitochondrial and metabolic inhibitors in H295R adrenal cells and perform a comprehensive analysis of steroid and metabolite profiling. We report that mitochondrial complex I inhibition by rotenone shifts cells toward anaerobic metabolism with a concomitant hyperandrogenic phenotype characterized by rapid stimulation of dehydroepiandrosterone (DHEA, 2 h) and slower accumulation of androstenedione and testosterone (24 h). Screening of metabolic inhibitors confirmed DHEA stimulation, which included mitochondrial complex III and mitochondrial pyruvate carrier inhibition. Metabolomic studies revealed truncated tricarboxylic acid cycle with an inverse correlation between citric acid and DHEA production as a common metabolic marker of hyperandrogenic inhibitors. The current study sheds light on a direct interplay between energy metabolism and androgen biosynthesis that could be further explored to identify novel molecular targets for efficient treatment of androgen excess disorders.

Factors predictive of the development of Levodopa-induced dyskinesia and wearing-off in Parkinson's disease.

The Stalevo Reduction in Dyskinesia Evaluation in Parkinson's Disease (STRIDE-PD) study compared the initiation of levodopa (l-dopa) therapy with l-dopa/carbidopa (LC) versus l-dopa/carbidopa/entacapone (LCE) in patients with Parkinson's disease. In the current study, the STRIDE-PD study population was investigated to determine the effect of l-dopa dose and other risk factors on the development of dyskinesia and wearing-off. Patients were randomized to receive LCE (n=373) or LC (n=372). Blinded assessments for dyskinesia and wearing-off were performed at 3-month intervals for the 134- to 208-week duration of the study. The patients were divided into 4 dose groups based on nominal l-dopa dose at the time of onset of dyskinesia (or at study conclusion if there was no dyskinesia): group 1, <400 mg/day (n=157); group 2, 400 mg/day (n=310); group 3, 401 to 600 mg/day (n=201); and group 4, >600 mg/day (n=77). Similar analyses were performed with respect to wearing-off and any motor complication. The times to onset and frequency of dyskinesia, wearing-off, or any motor complication were compared using the log-rank test (overall trend test) and a Cox proportional hazards model (pairwise comparisons). A stepwise Cox proportional hazards model was used to screen predictive factors in a multivariate analysis. The risk of developing dyskinesia and wearing-off increased in an l-dopa dose-dependent manner (P<0.001 for both). Analyses using l-dopa equivalent doses produced comparable results. Factors that were predictive of dyskinesia, in rank order, were: young age at onset, higher l-dopa dose, low body weight, North American geographic region, LCE treatment group, female gender, and more severe Unified Parkinson's Disease Rating Scale (UPDRS) Part II. Multivariate analyses identified similar predictors for wearing-off but included baseline UPDRS Part III and excluded weight and treatment allocation. The risk of developing dyskinesia or wearing-off was closely linked to l-dopa dose. The current results suggest that physicians should use the lowest dose of l-dopa that provides satisfactory clinical control to minimize the risk of both dyskinesia and wearing-off.