Sexual maturation among youth with ADHD and the impact of stimulant medication

Objective

Evaluate the differences in achieving puberty between ADHD and non-ADHD participants and the effects of medication on that process among ADHD participants.

Procedure

A subset of participants with ADHD from the Multimodal Treatment study of ADHD (n = 342) were compared with respect to Tanner staging to participants from a comparison group without ADHD (n = 159) at the 36-month follow-up assessment. Further comparisons were made for Tanner stages and Auxology of the participants in the ADHD group who were always (n = 61), never (n = 56), newly (n = 74) and inconsistently (n = 116) treated with stimulants.

Results

No statistically significant differences in Tanner stages of sexual development were found between the ADHD and non-ADHD groups at the age of assessment (between 10 and 14 years of age) or among the ADHD medication subgroups, although a trend was observed for stimulant-associated delayed pubertal initiation using auxological analysis.

Conclusion

Children with or without ADHD did not differ in Tanner stages at the 3-year follow-up assessment, and exposure to stimulant medication does not appear to affect sexual development within this age range.     

Continuity in features of anxiety and attention deficit/hyperactivity disorder in young preschool children

Anxiety disorders and attention deficit/hyperactivity disorder (ADHD) develop before school age, but little is known about early developmental pathways. Here we test two hypotheses: first, that early signs of anxiety and ADHD at 18 months predict symptoms of anxiety and ADHD at age 3½ years; second, that emotional dysregulation at 18 months predicts the outcome of co-occurring anxiety and ADHD at age 3½ years. The study was part of the prospective Norwegian Mother and Child Cohort Study (MoBa) at the Norwegian Institute of Public Health. The 628 participants were clinically assessed at 3½ years. Questionnaire data collected at 18 months were categorized into early behavioural scales of anxiety, ADHD, and emotional dysregulation. We investigated continuity in features of anxiety and ADHD from 18 months to 3½ years of age through logistic regression analyses. Anxiety symptoms at 3½ years were predicted by early signs of anxiety (Odds ratio (OR) = 1.41, CI = 1.15–1.73) and emotional dysregulation (OR = 1.33, CI = 1.15–1.54). ADHD symptoms at 3½ years were predicted by early signs of ADHD (OR = 1.51, CI = 1.30–1.76) and emotional dysregulation (OR = 1.31, CI = 1.13–1.51). Co-occurring anxiety and ADHD symptoms at 3½ years were predicted by early signs of anxiety (OR = 1.43, CI = 1.13–1.84), ADHD (OR = 1.30, CI = 1.11–1.54), and emotional dysregulation (OR = 1.34, CI = 1.13–1.58). We conclude that there were modest continuities in features of anxiety and ADHD through early preschool years, while emotional dysregulation at age 18 months was associated with symptoms of anxiety, ADHD, and co-occurring anxiety and ADHD at age 3½ years.     

Altered peripheral BDNF mRNA expression and BDNF protein concentrations in blood of children and adolescents with autism spectrum disorder

Findings from molecular genetic studies and analyses of postmortem and peripheral tissue led to the hypothesis that neurotrophins—as crucial moderators of neuroplasticity—impact on the pathophysiology of autism spectrum disorder (ASD). The study projects aimed to complement former results on the role of brain-derived neurotrophic factor (BDNF), a member of the neurotrophin family with fundamental impact on brain development and function. The purpose of this work was to investigate peripheral BDNF mRNA expression and BDNF protein concentrations in ASD as potential surrogates for the effects observed in the central nervous system. In a BDNF protein quantification study, serum concentrations were analyzed using Enzyme-Linked Immunosorbent Assays in 24 male patients with ASD, all with an IQ > 70 (age 13.9 ± 3.0 years) and 20 age- and gender-matched healthy control subjects (age 14.4 ± 2.1 years; p = 0.522). In a further independent project, a BDNF mRNA expression analysis, mRNA levels from total blood were assessed by quantitative real-time polymerase chain reaction in a sample of 16 male ASD patients (age 10.8 ± 2.2), 15 age- and gender-matched healthy controls (age 12.1 ± 2.2) and 15 patients with attention deficit hyperactivity disorder as a clinical control group (age 11.8 ± 2.2; p = 0.207). In the protein quantification project, significantly decreased BDNF serum concentrations were found in ASD cases compared to healthy control children (t = ?2.123, df = 42, p < 0.05). Analysis of covariance (ANCOVA) revealed this result in accordance with significant reductions in BDNF mRNA expression in ASD, observed in the mRNA expression study (F = 3.65; df = 2.43; p < 0.05); neither age nor IQ confounded the result, as indicated by ANCOVA (F = 3.961; df = 2.41; p < 0.05, η ²  = 0.162). Our study projects supported the notion that neurotrophins are involved in the pathophysiology of ASD. Further studies may eventually contribute to the identification of distinct peripheral mRNA expression and protein concentration patterns possibly supporting diagnostic and therapeutic processes.     

Subthreshold attention-deficit/hyperactivity disorder is associated with functional impairments across domains: a comprehensive analysis in a large-scale community study

This study compared children who experience attention-deficit/hyperactivity disorder (ADHD) symptoms but do not meet criteria (i.e., subthreshold ADHD) with those with the full syndrome and healthy controls. Presence of ADHD symptoms was determined in a nationwide community sample of 921 children, aged 8–11 years. The main outcome measures comprised attentional symptoms, comorbidity profiles, academic performance, and neurocognitive ability (i.e., ADHD Rating Scale, Child Behavior Checklist, Learning Disability Evaluation Scale, and Stroop Color-Word Test, respectively). Subthreshold ADHD was equally prevalent in boys and girls, and more prevalent in low-income families. Throughout all the outcome measurements, subthreshold ADHD was both a significantly milder condition than full syndrome ADHD and a significantly more severe condition than non-ADHD status. The findings were consistent across the total as well as the subtest scores, and after correction for multiple comparisons (p < 0.0017). Children with subthreshold ADHD were found to experience significant symptoms and functional impairments. The results of this study support the clinical relevance of subthreshold ADHD in a childhood population. Subthreshold diagnostic criteria for ADHD may be more sensitive in detecting ADHD symptoms in girls than the full syndrome criteria, and subthreshold clinical, cognitive, and behavioral symptoms of ADHD may occur in a subset of children who are possibly more sensitive to their environment. Further consideration about the diagnostic threshold for ADHD may particularly benefit girls and children in low-income families.     

Induction of Matrix Metalloproteinase-3 (MMP-3) Expression in the Microglia by Lipopolysaccharide (LPS) via Upregulation of Glycoprotein Nonmetastatic Melanoma B (GPNMB) Expression

Substantial evidence suggests that inflammation is an important contributor to many neurodegenerative disorders. Activated microglial cells play an important role in releasing pro-inflammatory factors, including tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) for inducing inflammation. Recently, some reports have suggested that glycoprotein nonmetastatic melanoma B (GPNMB) is highly expressed in microglia after LPS treatment. However, the role of GPNMB in activated microglia is not clearly understood. In this study, we used RT-PCR and Western blotting to detect GPNMB and matrix metalloproteinase-3 (MMP-3) expressions in activated microglia. GPNMB small interfering RNA (siRNA) or MMP-3 inhibitor was applied on microglial BV2 cells, and ELISA was performed to measure the expressions of TNF-α and IL-1β in BV2 cells. Levels of iNOS and NO in BV2 cells were also determined. We found that the levels of GPNMB and MMP-3 were significantly increased in BV2 cells after LPS treatment. Moreover, we found that GPNMB significantly upregulated the expression of MMP-3 in BV2 cells, and high expression of MMP-3 was dependent on the level of GPNMB. Inhibition of GPNMB or MMP-3 expression by GPNMB siRNA or MMP-3 inhibitor dramatically suppressed the expressions of TNF-α, IL-1β, iNOS, and NO in activated microglia. All of these results suggest that GPNMB is involved in the inflammatory responses of microglia.     

Seroprevalence of n-methyl-d-aspartate glutamate receptor (NMDA-R) autoantibodies in aging subjects without neuropsychiatric disorders and in dementia patients

n-methyl-d-aspartate glutamate receptors (NMDA-R) play a key role in learning and memory. Therefore, they may be involved in the pathophysiology of dementia. NMDA-R autoantibodies directed against the NR1a subunit of the NMDA-R, which were first identified as a specific marker for a severe form of encephalitis, cause a decrease in NMDA-Rs, resulting in cognitive impairment and psychosis. We examined the prevalence of NR1a NMDA-R autoantibodies in the serum and cerebrospinal fluid (CSF) of 24 patients with Alzheimer’s disease (AD), 20 patients with subcortical ischemic vascular dementia (SIVD), and 274 volunteers without neuropsychiatric disorder. The latter cases showed an association of seropositivity with age. Notably, the overall seroprevalence was not statistically different between dementia patients and matched controls. Further analysis of the patient samples showed that four patients with AD and three patients with SIVD had positive NMDA-R IgM, IgG, and/or IgA autoantibody titers in serum. These patients suffered from psychosis (with the exception of one case). CSF samples were negative for NMDA-R autoantibodies. We conclude that the seroprevalence of NMDA-R-directed autoantibodies is age-related. It has to be clarified by larger studies whether NMDA-R autoantibodies in peripheral blood may predispose patients with AD and SIVD to susceptibility for psychotic episodes if disturbances of blood–brain-barrier integrity occur.     

Ras Homolog Enriched in the Brain is Linked to Retinal Ganglion Cell Apoptosis after Light Injury in Rats

Ras homolog enriched in the brain (Rheb) is a small GTPase of the Ras family. It has been confirmed that Rheb activation not only regulates cell growth and migration but also induces neuron apoptosis after toxic stimuli. However, the function of Rheb in the retina is still not fully understood. To find out whether Rheb was involved in retinal neuron death, the expression profile of Rheb in light-damaged retinal ganglion cells (RGCs) of adult rats was investigated. Western blotting showed the expression of Rheb was significantly upregulated in the injured retina. Rheb was mainly detected in apoptotic RGCs by using double immunofluorescent staining. Active caspase-3 was upregulated and co-labeled with Rheb. Meanwhile, terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) showed that Rheb-positive RGCs underwent apoptosis after light exposure, which suggested that Rheb might be relevant to RGC apoptosis following phototoxicity. Furthermore, Western blotting and immunofluorescence showed that the expression profiles of CyclinD1 and cyclin-dependent kinase 4 (CDK4) were parallel with that of Rheb in a time–space dependent manner. Based on this study, it is speculated that Rheb might play an important role in physiological and pathological process in light-induced retina damage, which might provide a potential therapeutic avenue of retinal degeneration.     

Characterization of anti-inflammatory responses of norepinephrine in hepatitis induced by LPS: Effects on expression of IL-6, TNF-α and iNOS in liver of mice

Under septic conditions, Kupffer cells produce pro-inflammatory mediators which contribute to hepatic dysfunction, and whose levels can be modulated by endogenous factors including neurotransmitters such as norepinephrine (NE). We investigated the ability of NE to suppress Kupffer cell activation, in particular its effects on induction and activity of the inducible form of nitric oxide synthase (NOSII), interleukin 6 (IL-6) and tumor necrosis factor-alpha (TNF-α). In the present study used twenty one male NMRI mice (25 ± 5 g) that they divided into tree groups (n = 7). Negative control (normal saline), positive control (LPS), NE (～100 nM) is injected through the mouse tail vein 30 minutes before inducts inflammation by LPS (5 mg/kg for intraperitoneal). Changes in the levels of expression of TNF-α, IL-6 and iNOS genes in the liver induced by LPS injection for two hours studied by a semi quantitative RT-PCR method. The results showed that administration of LPS increased hepatic TNF-α, IL-6 and iNOS mRNAs. NE (～100 nM) reduces TNF-α, IL-6 and iNOS mRNA levels two hours after the injection. The most important have remarked effect norepinephrine in reducing iNOS; on the other hand, NE has a better influence on iNOS in liver tissue. These results indicate that high concentration of NE effectively suppress LPS-induced TNF-α, IL-6 and iNOS expression from liver tissue, suggesting that the down regulatory effect of NE on pro-inflammatory cytokine may represent a mechanism responsible for their beneficial effects in preventing inflammatory responses and tissue damage in sepsis.     

Evaluation of a psychoeducation programme for parents of children and adolescents with ADHD: immediate and long-term effects using a blind randomized controlled trial

Recent guidelines for the diagnosis and treatment of attention deficit hyperactivity disorder (ADHD) have claimed the possible benefits of psychoeducational techniques in the comprehensive management of ADHD. To evaluate the efficacy of a psychoeducation programme for parents of children and adolescents with ADHD in a clinical setting using a blind randomized trial. 81 children/adolescents with ADHD were randomly assigned for their families to receive either a well-structured psychoeducation programme (intervention group, n = 44), or a parent counselling and support intervention (control group, n = 37). Measures of child ADHD symptoms, psychopathology, quality of life and family stress were taken before and after intervention and after a year follow-up. Parents and evaluators were unaware of the condition received. Compared to the support control group, the psychoeducation group showed ADHD Index and cognitive/inattention levels significantly reduced after the intervention ended (Mann–Whitney U = 3.34; p = 0.001; Mann–Whitney U = 3.47; p = 0.001). An improvement in the pro-social domain was also observed after 1 year follow-up (Mann–Whitney U = ?2.37; p = 0.018), and clinical global impression found a statistically significant effect for severity over the time. Differences were initially found for the impact of the disorder in the family in different domains, including emotional and social functioning; these differences were no longer significant after alpha correction. No significant differences in quality of life or family stress were found in comparison with the control group. This psychoeducation programme is a valuable treatment for parents/carers of children/adolescents with ADHD, which needs to be considered when evaluating different non-pharmacological treatment options. Psychoeducation and other kind of non-pharmacological approaches need to be regarded not as a substitute, but as a complementary treatment to medications; these approaches might help other very crucial aspects of ADHD including social and familiar outcomes.     

PACAP Protects Against Inflammatory-Mediated Toxicity in Dopaminergic SH-SY5Y Cells: Implication for Parkinson’s Disease

There has been a growing recognition of the role of neuroinflammation caused by microglia-exaggerated release of inflammatory mediators in the pathogenesis of Parkinson’s disease (PD). Pituitary adenylate cyclase activating polypeptide (PACAP) is an endogenous 38 amino acid containing neuropeptide that has been shown to possess neurotrophic as well as neuroprotective properties. In this study, we sought to determine whether PACAP could protect SH-SY5Y dopaminergic cells against toxicity induced by inflammatory mediators. For this purpose, THP-1 cells which possess microglia-like property were stimulated by a combination of lipopolysaccharide (LPS) and interferon gamma (IFN-γ), and the media containing inflammatory mediators were isolated and applied to SH-SY5Y cells. Such treatment resulted in approximately 54 % cell death as well as a reduction in brain-derived neurotrophic factor (BDNF) and phosphorylated cyclic AMP response element-binding protein (p-CREB). Pretreatment of the SH-SY5Y cells with PACAP (1-38) dose-dependently attenuated toxicity induced by the inflammatory mediators. PACAP effects, in turn, were dose-dependently blocked by the PACAP receptor antagonist (PACAP 6-38). These results suggest protective effects of PACAP against inflammatory-induced toxicity in a cellular model of PD that is likely mediated by enhancement of cell survival markers through activation of PACAP receptors. Hence, PACAP or its agonists could be of therapeutic benefit in inflammatory-mediated PD.     

BDNF genetic variability modulates psychopathological symptoms in patients with eating disorders

The brain-derived neurotrophic factor (BDNF) gene may influence eating behavior, body weight and cognitive impairments. We aimed to investigate whether BDNF genetic variability may affect anthropometric and psychological parameters in patients with anorexia or bulimia nervosa (AN, BN) and/or modulate the risk for the disorder. A total of 169 unrelated female patients and 312 healthy controls were genotyped for two common BDNF single-nucleotide polymorphisms (SNPs), Val66Met and C-270T, and several selected tag-SNPs. Associated personality characteristics and psychopathological symptoms were assessed by the EDI-2 and SCL-90R inventories, respectively. No single SNP or haplotype played a relevant role in the risk for AN or BN. The rs16917237 TT genotype was significantly associated with increased weight (74.63 ± 16.58 vs. 57.93 ± 13.02) and body mass index (28.94 ± 6.22 vs. 22.23 ± 4.77) in the BN group after correcting for multiple testing. Haplotype analyses using a sliding window approach with three adjacent SNPs produced four loci of interest. Locus 3 (rs10835210/rs16917237/C-270T) showed a broad impact on the measured psychopathological symptoms. Haplotypes CGC and CGT in this locus correlated with scores in all three scales of the SCL-90R inventory, both in AN and BN patients. In contrast, the results of the EDI-2 inventory were largely unaffected. These preliminary results suggest that variability in the BDNF gene locus may contribute to anthropometric characteristics and also psychopathological symptoms that are common but not exclusive of ED patients.     

Validation of the World Health Organization’s Quality of Life Questionnaire with Parents of Children with Autistic Disorder

The World Health Organization’s Quality of Life Questionnaire-BREF (WHOQOL-BREF) has been used in many studies that target parents of children with Autistic Disorder. However, the measure has yet to be validated and adapted to this sample group whose daily experiences are considered substantially different from those of parents of children with typical development and parents of children with other disabilities. Therefore, this study was designed to examine the psychometric properties and the theoretical structure of the WHOQOL-BREF with a sample of 184 parents of children with Autistic Disorder. The factor structure for the WHOQOL-BREF was examined using exploratory and confirmatory factor analyses. Our analyses provided no evidence of a better model than the original 4-domain model. Nevertheless, some items in the measure were re-distributed to different domains based on theoretical meanings and/or clean loading criteria. The new model structure gained the measure’s required validity with parents of children with Autistic Disorder.     

The association between seizure predisposition and inflammation in a rat model of fatty liver disease

The association between inflammation and the induction of seizures is well-known. It has been reported that non-alcoholic fatty liver disease (NAFLD) is associated with a pro-inflammatory state, and systemic inflammation may trigger central nervous system inflammation. This study aims to identify the impact of inflammation in a rat model of fatty liver on the propensity and severity of pentylenetetrazol (PTZ)-induced seizures. Twenty-four male Sprague–Dawley rats were divided into four groups. Groups 1 and 2 were administered a 35 % fructose solution over 8 weeks to induce the development of fatty liver while Groups 3 and 4 were fed normally as controls. Groups 1 and 3 were given 70 mg/kg PTZ, determining Racine Convulsion Scores (RCS) and onset times of the first myoclonic jerks (FMJ). Groups 2 and 4 were administered 35 mg/kg of PTZ, then EEG recordings were obtained to evaluate spike percentages. TNF-α levels in brain and liver tissues were also measured. While RCS’s of fatty liver rats were higher than the control group (p > 0.05) as well as spike percentages (p < 0.05), FMJ onset time was significantly shorter. TNF-α levels in liver and brain tissues of the rats with NAFLD were significantly higher than the control rats. We found that rats with NAFLD demonstrated decreased seizure thresholds, possibly due to increased cytokine levels systemically and within the central nervous system. As such, epilepsy patients taking medications that may predispose the development of NAFLD must be carefully managed to prevent the possibility of increased seizure episodes.     

The ferric iron chelator 2,2′-dipyridyl attenuates basilar artery vasospasm and improves neurological function after subarachnoid hemorrhage in rabbits

We investigated the efficacy of the ferrous iron (Fe²⁺) chelator 2,2′-dipyridyl (DP) to attenuate cerebral vasospasm after subarachnoid hemorrhage (SAH). Thirty-six New Zealand white rabbits were randomly assigned to four groups: untreated control, SAH, SAH + dimethyl sulfoxide (DMSO) vehicle, and SAH + DP. SAH was induced by injection of autologous blood into the cisterna magna and then DP or vehicle was infused into the cistern magna for 5 days (20 mg/kg/day or an equal volume of DMSO). Neurological deficit score (NDS) was used to assess neurological function and cerebral angiography to measure basilar artery (BA) diameter following SAH. TUNEL staining was used to detect BA endothelial cell apoptosis, and immunohistochemistry and Western blotting to assess changes in caspase-3 protein levels 5 days post-SAH. The SAH + DP group had a significantly larger mean BA diameter and lower mean NDS post-SAH compared to the SAH + DMSO and SAH groups (p < 0.05). TUNEL-positive cell numbers and caspase-3 levels were significantly reduced in BA endothelial cells of the SAH + DP group as compared to the SAH and SAH + DMSO groups (p < 0.05). The iron chelator DP reduced vasospasm and neurological sequelae in rabbits, likely by chelating the Fe²⁺ in oxyhemoglobin and reducing oxidative stress-induced endothelial cell apoptosis.     

Increase in glial fibrillary acidic protein following neural trauma

Immunohistochemical staining and quantitative evaluation of glial fibrillary acidic protein (GFAP) were carried out in a stab wound model of neural trauma in the rat. Increased GFAP staining was detected in reactive cortical astrocytes in the vicinity of the wound at 3,7, and 30 d following injury. Western blots immunostained for GFAP also demonstrated an increase in GFAP in homogenates from the lesioned cortex, compared to the contralateral control side, on days 3, 7, and 30. Specific activity of GFAP expressed as a ratio of lesion/control values showed a fivefold increase from day 0 to day 7, with no further change on day 30. We conclude that neural trauma elicits a quantitative increase in GFAP in the rat cortex during the first week following injury. This increase correlates with both astrocyte hyperthrophy and proliferation. Thus, specific activity of GFAP is a reliable indicator of the onset and progression of astrogliosis in neural trauma.     

Low Bone Mineral Density in Friedreich Ataxia

Friedreich ataxia (FRDA) is the most common inherited neurodegenerative ataxia. Apart from predominant neurological features an involvement of the skeletal system in terms of scoliosis and foot deformities is frequent. Disease-related falls, mobility restrictions, and wheelchair-dependency in later disease stages might additionally compromise bone structure in FRDA. The aim of this pilot study was to systematically evaluate the bone status in a representative FRDA cohort. Twenty-eight FRDA patients became enrolled in this cross-sectional study. Neurological assessment, a questionnaire comprising the history of fractures and osteoporosis as well as osteodensitometric measurements complemented with general and bone-specific laboratory parameters were performed. The WHO Fracture Risk Assessment tool (FRAX®) was applied, calculating the 10-year risk of suffering an osteoporotic fracture. Six patients (21.4 %) presented with a bone mineral density below the expected range for age in at least one of the examined sites (femoral neck, lumbar spine, and forearm) irrespective of their gender. Corresponding Z scores were significantly lower compared to normative values for the femoral neck and lumbar spine. Vitamin D status was insufficient in 11 and deficient in 8 FRDA patients. There was a strong negative correlation between ataxia severity, GAA repeat expansion and bone density in the femoral neck of FRDA patients. This is the first report of an increased rate of low bone mineral density in FRDA. Given the increased risk of falls, this data rectifies routine bone mineral density measurements in FRDA which may help to initiate therapeutic interventions to prevent this condition.     

Glial Cell-Derived Neurotrophic Factor Attenuates Neuropathic Pain in a Mouse Model of Chronic Constriction Injury: Possible Involvement of E-cadherin/p120ctn Signaling

Treating neuropathic pain is a major clinical challenge, and several key molecules associated with nociception have been suggested as potential targets for novel analgesics. Many studies have reported the anti-nociceptive effects of glial cell-derived neurotrophic factor (GDNF), but the underlying mechanism remains largely unknown. The present study was performed to assess the effects of GDNF in a mouse model of chronic constriction injury (CCI)-induced neuropathic pain. We also determined the potential role of E-cadherin/p120 catenin (p120ctn) signaling in these effects. Mice received an intrathecal acute injection of PBS, GDNF, and DECMA-1 (an E-cadherin functional blocking antibody) or a combination of DECMA-1 with GDNF on the testing days. Our results demonstrated that CCI caused a rapid decrease in E-cadherin and membrane-associated p120ctn in the spinal dorsal horn. Together, these data demonstrated that E-cadherin-associated p120ctn was upregulated by GDNF and that this upregulation was inhibited by pre-treatment with DECMA-1. Moreover, DECMA-1 significantly inhibited the effect of GDNF on thermal hyperalgesia. These data suggest that GDNF might have a therapeutic potential for the treatment of CCI-induced neuropathic pain and that the E-cadherin/p120ctn might play a role in GDNF-induced attenuation of thermal hyperalgesia.     

Genome-wide analysis of DNA methylation in an APP/PS1 mouse model of Alzheimer’s disease

To investigate aberrant genome-wide CpG methylation patterns in cortex brain tissue of APP/PS1 mice and as compared to controls, which allows for identification of novel disease-associated genes. This study investigates the genome-wide DNA methylation profiles of the cortex from APP/PS1 transgenic mice and control mice using the Roche NimbleGen chip platform. Functional analysis was then conducted by Ingenuity Pathways Analysis system. The methylated DNA fragments in the genome of each sample were enriched by MeDIP and the whole-genome interrogations were hybridized to the Roche NimbleGen Human DNA Methylation 3x720 K CpG Island Plus RefSeq Promoter Array that cover 15,980 CpG islands and 20,404 reference gene promoter regions of the entire human genome. Analysis reveals 2346 CpG sites representing 485 unique genes as potentially associated with AD disease status pending confirmation in additional study. At the same time, these hyper-methylated genes display familial aggregation. An impairment of the transforming growth factor-β1 (TGF-β1) signaling pathway has been demonstrated to be specific to the AD brain and, particularly, to the early phase of the disease, supporting a role for epigenetic change of TGF-β1 in AD pathology. In future research, we will focus on TGF-β1, as it appeared to be the most promising candidate for AD.