Top PDF Intrabodies as therapeutics for Huntington's disease

Intrabodies as therapeutics for Huntington's disease

Intrabodies as therapeutics for Huntington's disease

(Khoshnan et al., 2002; Jackson et al., 2004). We find that it is also effective in an acute brain slice model of HD, and that it increases the turnover of HDx-1, with greater effect on the mutant than the wild type form. We also produced novel intrabodies, Happ1 and 3, which recognize the unique, P-rich epitope between the two polyP domains of Htt. The Happ intrabodies exhibit beneficial properties similar to those of MW7 such as preferential effects on the mutant form of Htt and increasing turnover without altering localization, but the Happs are effective at lower ratios to Htt than MW7. We found no evidence that the anti-PRR intrabodies bind to previously aggregated mHtt, suggesting that the observed reduction in aggregation is the indirect result of increased turnover of the soluble form of the protein, causing a shift away from the aggregated state. The increased turnover of mHDx-1 in the presence of either anti-polyP or anti-P- rich intrabodies suggests that this effect is a direct result of blocking these epitopes and therefore that this domain has a role in modulating stability of the mutant protein.
Show more

219 Read more

Nonallele-specific Silencing of Mutant and Wild-type Huntingtin Demonstrates Therapeutic Efficacy in Huntington s Disease Mice

Nonallele-specific Silencing of Mutant and Wild-type Huntingtin Demonstrates Therapeutic Efficacy in Huntington s Disease Mice

Huntington’s disease (HD) is a fatal neurodegenerative disease caused by mutant huntingtin (htt) protein, and there are currently no effective treatments. Recently, we and others demonstrated that silencing mutant htt via RNA interference (RNAi) provides therapeutic benefit in HD mice. We have since found that silencing wild-type htt in adult mouse striatum is tolerated for at least 4 months. However, given the role of htt in various cellular pro- cesses, it remains unknown whether nonallele- specific silencing of both wild-type and mutant htt is a viable therapeutic strategy for HD. Here, we tested whether cosilencing wild-type and mutant htt provides therapeu- tic benefit and is tolerable in HD mice. After treatment, HD mice showed significant reductions in wild-type and mutant htt, and demonstrated improved motor coordi- nation and survival. We performed transcriptional pro- filing to evaluate the effects of reducing wild-type htt in adult mouse striatum. We identified gene expression changes that are concordant with previously described roles for htt in various cellular processes. Also, several abnormally expressed transcripts associated with early- stage HD were differentially expressed in our studies, but intriguingly, those involved in neuronal function changed in opposing directions. Together, these encour- aging and surprising findings support further testing of nonallele-specific RNAi therapeutics for HD.
Show more

11 Read more

Transgenic animal models for study of the pathogenesis of Huntington’s disease and therapy

Transgenic animal models for study of the pathogenesis of Huntington’s disease and therapy

Abstract: Huntington’s disease (HD) is caused by a genetic mutation that results in polyglutamine expansion in the N-terminal regions of huntingtin. As a result, this polyQ expansion leads to the misfolding and aggregation of mutant huntingtin as well as age-dependent neurodegeneration. The genetic mutation in HD allows for generating a variety of animal models that express different forms of mutant huntingtin and show differential pathology. Studies of these animal models have provided an important insight into the pathogenesis of HD. Mouse models of HD include transgenic mice, which express N-terminal or full-length mutant huntingtin ubiquitously or selectively in different cell types, and knock-in mice that express full-length mutant Htt at the endogenous level. Large animals, such as pig, sheep, and monkeys, have also been used to generate animal HD models. This review focuses on the different features of commonly used transgenic HD mouse models as well as transgenic large animal models of HD, and also dis- cusses how to use them to identify potential therapeutics. Since HD shares many pathological features with other neurodegenerative diseases, identification of therapies for HD would also help to develop effective treatment for different neurodegenerative diseases that are also caused by protein misfolding and occur in an age-dependent manner.
Show more

10 Read more

Novel targets for Huntington’s disease: future prospects

Novel targets for Huntington’s disease: future prospects

Abstract: Huntington’s disease (HD) is an incurable, inherited, progressive, neurodegenerative disorder that is characterized by a triad of motor, cognitive, and psychiatric problems. Despite the noticeable increase in therapeutic trials in HD in the last 20 years, there have, to date, been very few significant advances. The main hope for new and emerging therapeutics for HD is to develop a neuroprotective compound capable of slowing down or even stopping the progres- sion of the disease and ultimately prevent the subtle early signs from developing into manifest disease. Recently, there has been a noticeable shift away from symptomatic therapies in favor of more mechanistic-based interventions, a change driven by a better understanding of the pathogenesis of this disorder. In this review, we discuss the status of, and supporting evidence for, potential novel treatments of HD that are currently under development or have reached the level of early Phase I/II clinical trials.
Show more

12 Read more

Making (anti-) sense out of huntingtin levels in Huntington disease

Making (anti-) sense out of huntingtin levels in Huntington disease

Recent advances have shown the potential of reducing mutant htt levels with oligonucleotide-based therapeutics. Reduction of both wild-type and mutant htt up to 70% was well tolerated in HD rodent models and non-human pri- mates [19]. Long-term suppression of wild-type and mutant htt might not be desirable because of htt’s anti-apoptotic function [20] and importance for cell survival in the adult brain [21,22]. A different approach would be an allele- specific reduction of mutant htt. This could be achieved with oligonucleotides directed against SNPs unique to the mutant htt transcript, or by targeting the expanded CAG repeat directly [23]. Although our allelic HTT mRNA ex- pression levels are in disagreement to that of Liu et al. [9], the overall differences in basal HTT mRNA in both studies are small. This shows that the levels of wild-type and mu- tant htt protein are not considerably different and provides feasibility for oligonucleotide therapeutics that are not com- pletely specific for the mutant HTT allele.
Show more

11 Read more

Targeting tauopathy with engineered tau-degrading intrabodies

Targeting tauopathy with engineered tau-degrading intrabodies

Utilizing the free-floating method, we subjected unilaterally injected AAVs encoding intrabody -K48R , intrabody -K63 , con- ventional intrabody, or AAV-control injected mice brain sections to pathological tau marker anti-AT8 (phospho-tau Ser202, Thr205, Thermo Scientific, MN1020B) and for de- tection of the various intrabodies anti-HA (Vector Labora- tories and Bethyl Laboratories, Inc.). Brain sections (30 μm) were picked that displayed a clear structured cross-section of the hippocampus, piriform, and entorhinal cortex re- gions. For quenching auto fluorescence, the sections were incubatated in sudan black (40 mg in 40 ml of 70% EtOH) for 10 min followed by washing with 0.03% PBS-Tween. Nonspecific binding was blocked by PBS 3% BSA, 3% nor- mal goat serum 0.1% Triton X-100. Brain sections were then incubated with primary antibodies, rabbit anti-HA (1: 1000), and anti-AT8 (1:500) overnight at 4C. Thereafter, the sections were washed three times in PBS for 10 min each followed by incubation with anti-streptavidin conju- gated 568 (Molecular Probes 1:500), and anti-rabbit conju- gated 488 (Molecular Probes 1:500) for 2 h at room temperature in the dark. Sections were then washed three times in PBS for 20 min each and mounted with ProLong Gold anti-fade reagent. Images were taken with an epi- fluorescence microscope at 4× magnification and quantified using MetaMorph as previously reported 27 . For analysis of p-tau (anti-AT8), the dentate gyrus, granule cell layer, mossy fibers, CA1, CA2, CA3 regions were traced from a minimum of 2 sections (300 μm) apart from each other per mouse using MetaMorph. To determine the percent area covered per region, we quantified the average ratio of p-tau (AT8) positive area from the contralateral to ipsilateral side. To measure total tau levels brain sections from mice injected unilaterally with AAVs encoding intrabody -K48R , intrabody -K63 , conventional intrabody, or AAV-control injected were subjected to immunohistochemistry with human anti-HT7 (Thermo Fischer, MN1000B). Free floating whole brain sections cut at 30 μm were incu- bated in .3% H 2 O 2 in TBS for 10 min at room
Show more

12 Read more

Drug Induced Liver Disease. Thomas S. Foster, Pharm.D. Integrated Therapeutics PHR 961

Drug Induced Liver Disease. Thomas S. Foster, Pharm.D. Integrated Therapeutics PHR 961

of acute and chronic lesions, including fatty.. Drug Induced Liver Disease.. z There are 800 million chemical.[r]

35 Read more

Magnetization Transfer Imaging in Premanifest and Manifest Huntington Disease

Magnetization Transfer Imaging in Premanifest and Manifest Huntington Disease

The regression analysis revealed several highly significant correlations between the MTR values and clinical measures (On-line Table 2). The disease burden score was significantly correlated with both cortical gray and white matter MTR peak height and mean MTR. The deep gray matter structures mainly showed a correlation of MTR peak height to the disease burden, except the right caudate nucleus and right putamen. The motor tests also correlated significantly with the MTR values in most regions of interest, predominantly with the UHDRS-total motor score and the tapping measure, and only minimally with the tongue measure. The cognitive measures showed correlations in the following regions: cortical gray matter, white matter, thalamus, left putamen, right pallidum, and left amygdala. The total functional capacity showed a cor- relation with white matter and the left putamen. The smell identification test was correlated to MTR values in both corti- cal gray and white matter, as in the caudate nucleus, amygdala, and thalamus. The MMSE and the measures of behavioral/ psychiatric functioning revealed no correlation to any struc- tures and are therefore not displayed in On-line Table 2.
Show more

6 Read more

Indirect tolerability comparison of Deutetrabenazine and Tetrabenazine for Huntington disease

Indirect tolerability comparison of Deutetrabenazine and Tetrabenazine for Huntington disease

The European Huntington’s Disease Network (EHDN) REGISTRY study reported that <10% of patients with HD taking medications receive tetrabenazine [18]. Clinical management of chorea is not uniform, and comorbid psy- chiatric comorbidities commonly seen in HD patients (e.g. delusions, behavioral outbursts, and psychosis) often ne- cessitate the use of neuroleptics, which can also provide improvements to choreiform movements. Of course, neu- roleptics also have significant side effects, such as worsen- ing parkinsonism, metabolic derangements (among other side effects), and poor tolerability which can limit their use. However, given our ITC findings, if improved tolerability of deutetrabenazine is replicated in larger HD populations, this would potentially allow for increased options for man- aging chorea and titration up to higher doses, thus maxi- mizing chorea control with fewer dose-limiting AEs [19].
Show more

11 Read more

Quantitative 7T Phase Imaging in Premanifest Huntington Disease

Quantitative 7T Phase Imaging in Premanifest Huntington Disease

One-way ANCOVA was used to compare LFS and normalized volume between controls and subjects with pmHD, with age and sex included as covariates. Next, to investigate the relationship between LFS and normalized volume, we performed 2 separate analyses. First, Pearson partial correlation was applied, control- ling for age, sex, and diagnosis. Second, logistic regression models were constructed to compare the accuracy of using LFS alone, normalized volume alone, and both values together as predictors to distinguish controls and subjects with pmHD. Finally, multi- variate linear regressions were applied to evaluate relationships between LFS and CAP S (disease burden), total motor UHDRS
Show more

7 Read more

Clinical and genetic features of Huntington disease in Sri Lanka

Clinical and genetic features of Huntington disease in Sri Lanka

Results: Thirty patients had fully penetrant (FP) CAG repeat mutations and 5 had reduced penetrant (RP) CAG repeat mutations. In the FP group mean ages of onset and diagnosis were 37.5 and 40.4 years, while in the RP group it was 63.0 and 64.8 years respectively. The age of diagnosis ranged from 15 to 72 years, with 2 patients with Juvenile onset (<20 years) and 3 with late onset (>60 years) Huntington disease. The symptoms at diagnosis were predominantly motor (32/35 -91%). Three patients had psychiatric and behavioral disorders. The age difference between onset and genetic diagnosis showed significant delay in females compared to males (p < 0.05). Twenty two (62.8%) had a positive family history, with 13/22 (59.1%) showing a paternal inheritance of the disease. In both groups, those with a family history had a significantly lower age of presentation (p < 0.05). The mean CAG repeat length in patients with FP alleles was 44.6 ± 5 and RP alleles was 37.2 ± 1.1. Age of onset and CAG repeat length of the HTT gene showed significant inverse correlation (p < 0.0005, R 2 = 0.727).
Show more

5 Read more

Overlap between age-at-onset and disease-progression determinants in Huntington disease

Overlap between age-at-onset and disease-progression determinants in Huntington disease

or her HTT CAG repeat size, after back-transformation of the residuals into the natural scale (figure e-4). Third, for every measurement occasion, we defined disease duration as the difference between the participant’s age at that occasion and his/her age at onset. Because disease duration was highly right- skewed (figure e-5A), we used age, which had a near-normal distribution (figure e-5B), as the time variable in our models. Including age as the time indicator also allowed for simulta- neous adjustment for possible age effects on disease pro- gression, which would not have been possible with inclusion of disease duration because of a high degree of collinearity be- tween age and disease duration. Based on this information, we then applied a mixed-effects model to the longitudinal data to estimate the interindividual variability in the rate of disease progression in patients with HD by including both fixed and random intercepts and slopes for age as follows:
Show more

9 Read more

Clinical manifestations of homozygote allele carriers in Huntington disease

Clinical manifestations of homozygote allele carriers in Huntington disease

In previous studies on HD homozygotes, the most frequent variable of disease severity was the difference in age at HD onset. In agreement with other studies, the length of the longer allele was the most contributing and consistent factor associ- ated with age at HD onset in both homozygotes and heterozygotes. 2,4,5,7,8,28 These results suggest that CAG repeat expansion in HD determines age at onset in a fully dominant fashion. 28,29 Age at HD onset in our homozygote participants was similar to that of the Lee et al. 28 study, but lower than reported by Squitieri et al. 2 It should be mentioned, however, that this dif- ference might be due to the greater expansion in the longer allele in our homozygote sample, compared to the Squitieri et al. 2 study. In any case, the small number of homozygotes in both studies 2,28 does not allow us to draw definitive conclusions. The underlying mechanisms of the lack of a significant ex- pression of a double mutant gene dosage in HD are not well- understood. On one hand, it has been proposed that biallelic mutation in HD might be deleterious in patients, due to lack of protective function of the wild-type huntingtin or mito- chondria impairment. 2,30,31 On the other hand, the level of mutant huntingtin protein produced from a single allele ap- parently exceeds any minimum threshold required to trigger pathogenesis (at a rate determined primarily by its CAG re- peat length), and that hypothetically neither additional mu- tant protein nor the absence of any normal protein further alters the rate of pathogenesis leading to motor onset. 28 In spite of that, it is also important to consider the potential modifying effect of genetic factors on HD clinical course, beside the CAG repeat length of the HTT gene. In a recent genome-wide disease progression association study, single nucleotide polymorphism (SNP) encoding an amino acid change (Pro67Ala) in MSH3 32 was shown to have an effect on disease progression. Each copy of the minor allele at this SNP was associated with a 0.4 units per year (95% CI 0.16–0.66) reduction in the rate of change of the TMS-UHDRS, and a reduction of 0.12 units per year (95% CI 0.06–0.18) in the rate of change of TFC in heterozygotes. 32 In this scenario, identification and assessment of individual genetic and envi- ronmental factors should contribute to define the possible effect of the second expanded allele on the variance of HD phenotype and progression.
Show more

9 Read more

Neurology outreach clinic for Huntington disease in PeruLessons for neurodegenerative diseases

Neurology outreach clinic for Huntington disease in PeruLessons for neurodegenerative diseases

1. Importance of consistent access Caregiver: I have to wait 2 months for when you come with the campaign so you can see him. But in those 2 months, things can happen and I have to wait. As I ’ ve said, the disease, it ’ s not that you come with the campaign and that ’ s it, and you are good, no the disease is constant … We should have … everyone who has a family member with this condition, someone specialized 24 hours per day. 2. Preference for home visits Interviewer: Would you prefer to have doctor ’ s visits here in your home or in the health center?
Show more

5 Read more

Treatment with a herbal formula B401 enhances neuroprotection and angiogenesis in the R6/2 mouse model of Huntington&rsquo;s disease

Treatment with a herbal formula B401 enhances neuroprotection and angiogenesis in the R6/2 mouse model of Huntington&rsquo;s disease

Abstract: Huntington’s disease (HD) is a neurodegenerative disease characterized by motor dysfunction and early death. Despite years of research, the mechanisms responsible for chronic neurodegeneration of HD remain elusive. Chinese traditional medicines might provide new insights or new therapy for HD. The Chinese herbal formula B401 is a well-known Taiwan–US patent formula and a health supplement for promoting blood circulation and enhancing brain function. This study aimed to elucidate the neuroprotective effects of the Chinese herbal formula B401 on the syndrome of HD. Then, we compared the life span and body weight of R6/2 HD mice with and without oral B401 treatment. The ameliorative effects of B401 on the symptom of HD mice were investigated through behavior tests. Expressions of proteins for neuroprotection, angiogenesis, and inflammation in the brain tissue of R6/2 HD mice were compared by using immunostaining and Western blotting techniques. Our study in vitro showed that viabilities of glutamate-treated SH-SY5Y cells were significantly increased under B401 treatment. Our results in vivo showed that duration of survival was increased, body weight loss was reduced, and motor ability was improved in R6/2 HD mice under oral B401 treatment. Subcutaneous microcirculation was enhanced in 3-month R6/2 HD mice under intraperitoneal B401 injections as observed by using moorFLPI laser Doppler imager. Atrophy of cerebrum, midbrain, and cerebellum in 3-month R6/2 HD mice under oral B401 treatment was alleviated as observed by utilizing magnetic resonance imaging. Evidence from immunostaining and Western blotting analysis showed that expressions of mutant huntingtin and tumor necrosis factor-alpha were reduced, while expressions of brain-derived neurotrophic factor and vascular endothelial growth factor were enhanced in the brain tissue of 2-month R6/2 HD mice under oral B401 treatment. We suggest that the herbal formula B401 can be developed as a medical supplement for ameliorating neurodegenerative diseases of HD via reducing mutant huntingtin aggregation and excitotoxicity, enhancing neuroprotection and angiogenesis, and alleviating inflammation in the brain.
Show more

14 Read more

Dicarbonyls and glyoxalase in disease mechanisms and clinical therapeutics

Dicarbonyls and glyoxalase in disease mechanisms and clinical therapeutics

g l y c e r a l d e h y d e - 3 - p h o s p h a t e ( G A 3 P ) a n d dihydroxyacetonephosphate (DHAP) - 0.05 – 0.1 % of flux. GA3P was ca. 8-fold more reactive than DHAP in degrading to MG but as the concentration ratio of DHAP/GA3P in cells in situ is ca. 9 or similar [9], both of these triosephosphates are important sources of MG formation in physiological systems in situ [10]. MG formation is a minor fate of triosephosphates: early studies with red blood cells suggested only 0.089 % glucotriose (2 x glucose consumption) was converted to MG [11] and our subsequent studies with endothelial cells and fibroblasts suggest a similar flux. The rate of total cellular formation of MG was estimated to be ca. 125 μmol/kg cell mass per day [11], which for an adult human of 70 kg body mass and 25 kg body cell mass [12] equates to a predicted whole body rate of formation of ca. 3 mmol MG per day (or ca. 3 mg/kg body weight/day). MG is also formed by the oxidation of acetone catalysed by cytochrome P450 2E1 in the catabolism of ketone bodies [13] – which is low except where ketone bodies are increased as in diabetic ketoacidosis, prolonged (>3 days) fasting or low calorie diet [13–15]. MG may also be formed from the oxidation of aminoacetone by semicarbazide amine oxidase (SSAO) in the catabolism of threonine [16]. Recent estimates of the concentration and rates of metabolism of aminoacetone in the presence and absence of SSAO inhibitor suggest this pathway has a flux of ca. 0.1 mmol MG per day in human subjects [17] or ca. 3 % of total MG formation. Vascular adhesion protein-1 is considered the origin of SSAO activity in mammals in vivo [18]. It is found in plasma, endothelium, adipose tissue and smooth muscle and increases ca. 2-fold in congestive heart failure, diabetes and inflammatory liver diseases [19], and may relat- edly increase MG formation in these conditions. MG is also formed by the degradation of proteins glycated by glucose and the degradation of monosaccharides [20]. Under physiological conditions with low level phosphate and chelation of trace metal ion, the predicted flux of MG formation from glycated protein degradation is ca. 0.2 mmol MG per day or ca. 7 % of total MG formation. Dietary contributions to MG exposure from food are normally relatively low: sweetened soft drink,
Show more

14 Read more

Presentation and care of a family with Huntington disease in a resource-limited community

Presentation and care of a family with Huntington disease in a resource-limited community

We were also able to discuss a misperception among members of the family regarding inheritance. At issue is the incorrect belief that a parent who is symptomatic during procreation or pregnancy might “ cause ” the trait to be passed on to her offspring. Since obtaining a definitive diagnosis, we have worked towards dispelling this myth, and to instead provide information regarding inheritance and progression of the disorder. Other at- risk individuals spoke of the disorder as being a “ curse ” that affects some members of the family. The idea of a curse is different from, but has parallels with how some cancer patients understand their disease [36]. Since many family members have internet access we were also able to direct family members to the appropriate on-line resources relevant to HD.
Show more

8 Read more

HUNTINGTON DISEASE: CURRENT ADVANCES IN PATHOGENESIS AND RECENT THERAPEUTIC STRATEGIES

HUNTINGTON DISEASE: CURRENT ADVANCES IN PATHOGENESIS AND RECENT THERAPEUTIC STRATEGIES

immunofluorescence showed a significant and progressive grade-dependent reduction in the number of mitochondria in spiny striatal neurons, with marked alteration in size. Consistent with mitochondrial loss, there was a reduction in COX2 protein levels using western analysis that corresponded with disease severity. In addition, both mitochondrial transcription factor A, a regulator of mitochondrial DNA (mtDNA), and peroxisome proliferator activated receptor-co-activator gamma-1 alpha, a key transcriptional regulator of energy metabolism and mitochondrial biogenesis, were also significantly reduced with increasing disease severity. Abnormalities in mitochondrial dynamics were observed, showing a significant increase in the fission protein Drp1and a reduction in the expression of the fusion protein mitofusin. Mitochondrial PCR array profiling in HD caudate nucleus specimens showed increased mRNA expression of proteins involved in mitochondrial localization, membrane translocation and polarization and transport that paralleled mitochondrial derangement. These findings reveal that there are both mitochondrial loss and altered mitochondrial morphogenesis with increased mitochondrial fission and reduced fusion in HD. These findings provide further evidence that mitochondrial dysfunction plays a critical role in the pathogenesis of HD. [70]
Show more

11 Read more

Huntington Beach AFFORDABLE HOUSING. The City of Huntington Beach and the Huntington Beach Redevelopment Agency

Huntington Beach AFFORDABLE HOUSING. The City of Huntington Beach and the Huntington Beach Redevelopment Agency

Located on Main Street behind the Seacliff Shopping Center, the Fountains at Huntington Beach consist of 204 one-bedroom and 67 two-bedroom apartments with a total of 271 units. The luxurious senior apartments are spread among six buildings in the midst of a rose garden, barbeques, a heated pool and spa, horseshoe pits, a putting green, and a croquet field. For rental information, call (714) 960-1600.

19 Read more

Bioenergetics in fibroblasts of patients with Huntington disease are associated with age at onset

Bioenergetics in fibroblasts of patients with Huntington disease are associated with age at onset

In addition to progressive motor disturbances, neuropsychiatric symptoms, and cognitive decline, patients with Huntington disease and premanifest mutation carriers suffer from un- intended weight loss. 6,7 Recently, we demonstrated that this weight loss was associated with a faster rate of disease pro- gression independent of CAG repeat number. 8 Various evi- dence indeed indicates that disturbances in energy metabolism and mitochondrial defects play a role in Hun- tington disease pathology. 9–11 Furthermore, mitochondrial metabolism was found to be impaired in peripheral tissues of patients with Huntington disease, including lymphoblastoid cell lines and skin fibroblasts. 12–15 In support of the associa- tion between mitochondrial defects and Huntington disease symptomology, Huntington disease characteristics emerged in humans after accidental exposure to 3-nitropropionic acid (3-NP), a mitochondrial toxin that selectively inhibits the activity of mitochondrial complex II. 16–19 However, to what extent differences in energy metabolism are associated with the onset of Huntington disease symptoms independent of the CAG repeat number is unknown. Therefore, the aim of our study was to investigate whether differences in energy metabolism were present in fibroblast cell lines from patients with Huntington disease with identical CAG repeat sizes but a large difference in age at onset.
Show more

13 Read more

Show all 10000 documents...