In Utero Exposure to Valproic Acid Induces Neocortical Dysgenesis via Dysregulation of Neural Progenitor Cell Proliferation/Differentiation.

Valproic acid (VPA), a widely used antiepileptic drug, is an inhibitor of histone deacetylases, which epigenetically modify cell proliferation/differentiation in developing tissues. A series of recent clinical studies in humans reported that VPA exposure in utero impaired histogenesis and the development of the central nervous system, leading to increased risks of congenital malformation and the impairment of higher brain functions in children. In the present study conducted in mice, we report that VPA exposure in utero (1) increases the amount of acetylated histone proteins, (2) alters the expression of G1-phase regulatory proteins, (3) inhibits the cell cycle exit of neural progenitor cells during the early stage of neocortical histogenesis, and (4) increases the production of projection neurons distributed in the superficial neocortical layers in embryonic brains. Together, our findings show that VPA exposure in utero alters proliferation/differentiation characteristics of neural progenitor cells and hence leads to the neocortical dysgenesis. SIGNIFICANCE STATEMENT: This study provides new insight into the mechanisms of how an altered in utero environment, such as drug exposure, affects the generation of neurons prenatally. The antiepileptic drug valproic acid (VPA) is a good target molecule as in utero exposure to VPA has been repeatedly reported to increase the risk of nervous system malformations and to impair higher brain functions in children. We show that VPA decreases the probability of differentiation of the neural progenitor cells (NPCs) in mice, resulting in an abnormally increased number of projection neurons in the superficial layers of the neocortex. Further, we suggest that histone deacetylase inhibition by VPA may be involved in the dysregulation of proliferation/differentiation characteristics of NPCs.

Manifestations and characteristics of congenital adrenal hyperplasia-associated encephalopathy.

BACKGROUND: This study aimed to clarify the characteristics of acute encephalopathic episodes in patients with congenital adrenal hyperplasia (CAH), which we termed "CAH-associated encephalopathy (CAHE)." METHODS: This retrospective study was conducted using a questionnaire as a nationwide survey of patients with CAH with acute encephalopathy and related episodes. RESULTS: Fifteen patients were recruited on the bases of clinical data that supported a diagnosis of CAHE. Fourteen patients displayed seizures at onset, and 12 patients exhibited refractory seizures. Deep coma lasting >24h was noted in 12 patients. Neuroimaging studies revealed some heterogeneous features. Diffuse or focal edematous lesions in the cerebrum, which produce high signal intensity on diffusion-weighted magnetic resonance imaging or low density on computer tomography, were found in the acute period in all 15 patients. In the chronic period, 14 patients survived, 11 of whom had some degree of neurological sequelae. Moreover, various degrees of cerebral shrinkage were observed in 11 of 14 surviving patients. Surprisingly, there were no abnormal neuroimaging findings in the basal ganglia, brainstem, and cerebellum in any patient. CONCLUSION: Our results indicated that patients with CAH have a risk of developing CAHE, and thus, they should be followed closely because not only status epilepticus or deep coma but also minor symptoms, such as fever and nausea, may lead to CAHE. Because CAHE may feature some heterogeneous encephalopathic episodes, further validation is needed to clarify its etiology.

Persistent hypertension despite successful dilation of a stenotic renal artery in a boy with neurofibromatosis type 1.

Hypertension is one of the major complications in neurofibromatosis type 1 (NF1). It is known to be caused by renal artery stenosis or pheochromocytoma. However, more than half of hypertensive patients with NF1 do not have either disorder. We report here on a 13-year-old male with NF1 who had hypertension and a stenosis of the right renal artery associated with elevated renal vein renin on the diseased side. He underwent percutaneous transluminal renal angioplasty. In spite of successful dilation of the artery and normalized renin level, high blood pressure persisted beyond 6 months requiring antihypertensive medication. His wide pulse pressure suggested arterial stiffness due to NF1 vasculopathy. We posit that the cause of hypertension in this patient was considered to be arterial stiffness ascribed to NF1 vasculopathy rather than renal artery stenosis. Increased pulse pressure supports the hypothesis. This marker of arterial stiffness can be assessed non-invasively and should be evaluated routinely in NF1.

Catastrophic autonomic crisis with cardiovascular collapse in spinal muscular atrophy with respiratory distress type 1.

Spinal muscular atrophy with respiratory distress type 1 (SMARD1) is a rare motor neuron disease that can result in dysautonomia but is usually only mildly symptomatic. We report a young girl with SMARD1 who had a catastrophic autonomic crisis with resultant permanent brain damage during an interhospital transfer. Although she was only mildly symptomatic prior to the transfer, in retrospect, her baseline autonomic function analysis had sympathetic hyperactivity without a typical circadian rhythm, indicating the presence of severe underlying dysautonomia. Because this underlying dysautonomia seemed markedly aggravated by the psychological stress, careful autonomic evaluation and management are warranted in patients with SMARD1.

Hydrocephalus with Hirschsprung disease: severe end of X-linked hydrocephalus spectrum.

L1CAM molecule is a cell adhesion molecule in nervous and enteric systems and is responsible for X-linked hydrocephalus (XLH) spectrum, which is a rare condition with severe congenital hydrocephalus, dysgenesis of the corpus callosum, intellectual disability, spasticity, and adducted thumbs. Several cases of XLH accompanied by Hirschsprung disease (HSCR) have been reported in the literature, but whether HSCR results from a gain-of-function mutation in cases with XLH, i.e., a neomorphic mutation, or the severe end of the L1CAM mutation spectrum remains unclear. The present patient was a Japanese boy with severe congenital hydrocephalus with aqueductal stenosis as well as hypoplasia of the corpus callosum. HSCR had been confirmed by a biopsy. A mutation analysis of the L1CAM gene showed a C61T mutation in exon 1, resulting in a truncating nonsense mutation at amino acid position 21 and producing an extremely short protein that was unlikely to interact with other proteins. These findings suggest that XLH-HSCR represents the severe end of the XLH spectrum, rather than a neomorphic mutation. A thorough abdominal investigation to rule out HSCR should be considered in patients with XLH accompanied by severe constipation.

Posterior cerebral artery dissection on a serial magnetic resonance angiography.

Posterior cerebral artery (PCA) dissection in children seldom is reported in the literature. This is the second report of acute PCA dissection with infarct occurring in a young child. A serial magnetic resonance angiography demonstrated a delayed and transient narrowing of the arterial caliber, which was consistent with a focal PCA dissection with delayed vascular recanalization. PCA dissection should be included in the causes of infarct in children and a thorough and serial neurovascular imaging should be considered if no cause of stroke is found.

Reversible diffuse white matter lesion in Alagille syndrome.

A boy with genetically confirmed Alagille syndrome was incidentally found to manifest striking diffuse hyperintensity of the white matter on T(2)-weighted cranial magnetic resonance images. He never exhibited signs of hepatic encephalopathy. For his progressive liver failure, he underwent a live-donor liver transplant at age 2 years, which unexpectedly resulted in a near-complete resolution of the diffuse white matter lesion. Reversible white matter lesions attributed to cerebral edema were reported in adult patients with liver cirrhosis, but not in the pediatric population. The diffuse reversible white matter lesion in the present case demonstrated T(2) hyperintensity, coupled with restricted diffusion confirmed by apparent diffusion coefficient, and was suggestive of etiologies such as ischemia or cytotoxic edema rather than vasogenic edema.

Protective role of anti-synthetic hinge peptide antibody for glomerular deposition of hypoglycosylated IgA1.

BACKGROUND: The KM mouse lacks endogenous genes for immunoglobulins and carries the entire human IgH locus and the IgLk transgene. Therefore, human IgA1 does not provoke a hetero-immune response. We had observed mesangial IgA deposits in KM mice given desialo-degalacto (DeS/DeGal) IgA1. METHODS: In this study, the mice were immunized with synthetic IgA1 hinge (glyco-)peptide before administration of DeS/DeGal IgA1, and the effects of the pre-immunization were evaluated. Mice were divided into sHP, 5GalNAc-sHP and non-immunization groups. In two pre-immunization groups, KLH-conjugated sHP or KLH-5GalNAc-sHP, which has five GalNAc residues, was subcutaneously given three times every 2 weeks. Two weeks after the final pre-immunization, DeS/DeGal IgA1 was administered daily for 5 weeks. Serial serum levels of anti-sHP and anti-IgA1 antibodies were evaluated by ELISA. On the day of the last administration of IgA1, renal biopsy was performed. RESULTS: Mesangial IgA deposits were observed in all non-immunized mice. In pre-immunized mice, IgA deposition was not detected in 6 of 13 sHP mice and 1 of 4 5GalNAc-sHP mice. The intensities of IgA deposits were significantly different between sHP groups and non-immunized (P = 0.003) groups. There was a significant inverse correlation between the intensities of IgA deposits and the anti-sHP antibody titers (P = 0.016). CONCLUSIONS: These results suggest that the anti-IgA1 hinge peptide antibody plays a role in the inhibition of glomerular IgA deposition.

Serum under-galactosylated IgA1 is increased in Japanese patients with IgA nephropathy.

BACKGROUND: Immunoglobulin A nephropathy (IgAN) is characterized by an aberrant structure of O-glycans in the IgA1 hinge region. Recently, under-galactosylated IgA1 has been found to be increased in Caucasian IgAN patients. Thus, we examined this in Japanese IgAN patients. METHODS: An enzyme-linked immunosorbent assay of binding between Helix aspersa (HAA) and serum IgA was performed in Japanese IgAN patients and the HAA-IgA binding levels were compared among IgAN patients (n = 41), patients with other forms of kidney disease (OKD, n = 43) and healthy controls (n = 38). The clinicopathological severity of IgAN was then analysed between patients with high and low HAA-IgA binding levels. The levels were also compared in 11 patients before and after the combination of tonsillectomy and steroid pulse therapy. Furthermore, we examined the O-glycan structure of IgA1 hinge glycopeptides by mass spectrometry (MS). RESULTS: The HAA-IgA binding levels were significantly higher in IgAN patients compared with either healthy controls (P = 0.0025) or those with OKD (P = 0.016). To reflect the absolute level of under-galactosylated IgA, we multiplied the HAA-IgA binding level by the serum IgA concentration to produce an indicative value. The specificity and sensitivity of this value were 89% and 66%, respectively. MS showed that peak distribution of IgA1 hinge glycopeptides was shifted to smaller molecular weights in high HAA-IgA-binding IgAN patients. There was no correlation between the HAA-IgA binding level and either disease severity or the use of combination therapy. CONCLUSIONS: HAA-IgA binding is significantly increased in Japanese IgAN patients. This potential IgAN marker is not affected by disease severity or therapeutic intervention.

Accumulation of bisphenol A in hemodialysis patients.

Bisphenol A [BPA, 2,2-bis(4-hydoxyphenyl)propane], an industrial chemical used in the production of polycarbonate, epoxide resin, and polyarylate, is considered to be an endocrine-disrupting chemical. BPA may be present in some hollow-fiber dialyzers used in hemodialysis. In this study, we tested the amounts of BPA eluted from various hollow fibers. Furthermore, we measured the BPA concentration in the sera of 22 renal disease predialysis patients, as well as 15 patients who were receiving hemodialysis, to see if there is BPA accumulation in these patients. The elution test of BPA showed that a much larger amount of BPA was eluted from polysulfone (PS), and polyester-polymeralloy hollow fibers. Among renal disease patients who had not undergone hemodialysis, the serum BPA concentration increased as the renal function deteriorated, showing a significant negative association. In a crossover test between PS and cellulose (Ce) dialyzers, the predialysis serum BPA concentration of PS dialyzer users decreased after changing to a Ce dialyzer, and the serum BPA increased again after switching back to PS dialyzers. In patients who were using PS dialyzers, the BPA level significantly increased after a dialysis session. However, in the Ce dialyzer users, the BPA level decreased. Since accumulation of BPA could affect the endocrine or metabolic system of the human body, it is important to perform further investigations on dialysis patients.

Structural analyses of O-glycan sugar chains on IgA1 hinge region using SELDI-TOFMS with various lectins.

The aim of the study was to develop a simple and precise method for identifying glycosylation of the IgA hinge region using surface-enhanced laser desorption/ionization (SELDI)-TOFMS with a lectin-coupled ProteinChip array. Serum IgA was isolated using an anti-IgA antibody column. Following reduction, alkylation, and trypsin digestion, the IgA fragments were applied on the ProteinChip coupled with jacalin, peanut agglutinin (PNA), or Vilsa villosa lectin (VVL). The SELDI-TOFMS peaks corresponding to the fragments containing IgA1 hinge glycopeptides trapped by each lectin were compared. The jacalin-, PNA-, and VVL-immobilized ProteinChips detected 13, 4, and 2 peaks, respectively. One major peak was confirmed as a glycopeptide by MS/MS analysis. These results suggest that a lectin-immobilized ProteinChip assay can be used to simplify the procedures for the analyses of the O-glycans in IgA1 hinge. This method potentially makes it possible to identify a disease-specific glycoform by selecting the appropriate ligand-coupled ProteinChip array.