The increase of Nrf2 m6A modification induced by FTO downregulation promotes hippocampal neuron injury and aggravates the progression of epilepsy in a rat model.

Epilepsy is a common chronic neurological disorder characterized by widespread neuronal death. The purpose of this study was to investigate the role of nuclear factor erythroid 2-related factor 2 (Nrf2) m6A methylation in epilepsy. To create epileptic models, the rats were given Lithium chloride and pilocarpine, and isolated primary rat hippocampal neurons were cultured in an Mg2+ -free medium. The frequency of seizures was recorded in the epilepsy group of rats. The functional tests included TUNEL, MTT, and flow cytometry. Mechanistically, RNA degradation assay, RNA immunoprecipitation, and methylated RNA immunoprecipitation were performed. In epileptic models, Nrf2 and fat mass and obesity-associated (FTO) levels were downregulated, whereas YT521-B homology (YTH) domain family protein 2 (YTHDF2) was upregulated. Additionally, in epileptic models, there was a rise in the m6A methylation level of Nrf2 mRNA. Overexpressing FTO increased cell viability and reduced apoptosis, but Nrf2 interference reversed these effects. Meanwhile, FTO overexpression decreased the m6A methylation of Nrf2 mRNA. Moreover, YTHDF2 bound to Nrf2 mRNA and decreased its stability. Furthermore, FTO overexpression reduced seizure frequency in rats and inhibited hippocampal neuron apoptosis via lowering the m6A methylation level of Nrf2 mRNA. Overexpressing FTO reduced m6A methylation of Nrf2 mRNA, increased cell viability, suppressed apoptosis, and slowed the progression of epileptic diseases, which is linked to YTHDF2 binding to m6A-modified Nrf2 and promoting its degradation, as well as downregulating Nrf2 expression in hippocampal neurons.

Weakness in both lower limbs for 1 week and blepharoptosis for 3 days in a boy aged 1 year and 7 months. / ç”·æ€§å¹¼å„¿åŒä¸‹è‚¢æ— åŠ›1周伴眼睑下垂3 d.

A boy, aged 1 year and 7 months, was hospitalized due to weakness in both lower limbs and blepharoptosis, which showed progressive aggravation and developed into irregular breathing. Neurological examinations showed lethargy, blepharoptosis, grade 4 muscle strength of both upper limbs, grade 3 muscle strength of both lower limbs, and disappearance of tendon reflex. Laboratory tests revealed albuminocytological dissociation in cerebrospinal fluid, disappearance of H reflex, and positive serum anti-GD1b IgG. The boy was finally diagnosed with Guillain-Barré syndrome (GBS) overlapping with Miller-Fisher syndrome and Bickerstaff brainstem encephalitis. He recovered and was discharged after treatment including immunoglobulin, plasma exchange, and respiratory support. The GBS overlap syndromes in children have strong clinical heterogeneity due to the injury of both peripheral nerve and brainstem, among which anti-GD1b antibody-related GBS overlap syndromes have special clinical manifestations and complex neuroelectrophysiological changes and are thus difficult to diagnose. Nerve conduction velocity tests, especially H reflex test, should be performed for children with weakness in both lower limbs and blepharoptosis.

[Progressive psychomotor regression for 2.5 years in a boy aged 5 years]. / 5岁男童进行性智力运动功能倒退2.5年.

A boy, aged 5 years, attended the hospital due to progressive psychomotor regression for 2.5 years. Motor function regression was the main manifestation in the early stage, and brain MRI and whole-exome sequencing (WES) of the family showed no abnormalities. After the age of 4 years and 9 months, the boy developed cognitive function regression, and brain MRI showed cerebellar atrophy. The reanalysis of WES results revealed a compound heterozygous mutation, [NM_000520, c.784C>T(p.His262Tyr]), c.1412C>T(p.Pro471Leu)], in the HEXA gene. The enzyme activity detection showed a significant reduction in the level of ß-hexosaminidase encoded by this gene. The boy was diagnosed with juvenile Tay-Sachs disease (TSD). TSD has strong clinical heterogeneity, and cerebellar atrophy may be an important clue for the diagnosis of juvenile TSD. The reanalysis of genetic data when appropriate based on disease evolution may improve the positive rate of WES.

[Fever for 2 months and disturbance of consciousness for 1 week in a preschool-aged girl].

Rapid-onset obesity with hypothalamic dysfunction, hypoventilation, and autonomic dysregulation syndrome (ROHHADS) is a rare multi-system disease, and delayed diagnosis and treatment may lead to catastrophic cardiopulmonary complications. As far as we know, no patient with ROHHADS has been reported in China, and this article reports a child with ROHHADS to improve the awareness of this disease among clinicians. A girl, aged 3 years, had the clinical manifestations of rapid weight gain, fever, disturbance of consciousness, and convulsion. The physical examination showed a body weight of 20 kg, somnolence, irregular breathing, and stiff neck. She had increased blood levels of prolactin and follicle-stimulating hormone and hyponatremia. The lumbar puncture showed an increased intracranial pressure. The brain MRI and magnetic resonance venography showed symmetrical lesions in the periventricular region and venous thrombosis in the right transverse sinus and the superior sagittal sinus. The sleep monitoring showed hypopnea. The girl was finally diagnosed with ROHHADS and intracranial venous thrombosis. She recovered after symptomatic treatment including decreasing intracranial pressure, anticoagulation, and respiratory support. The possibility of ROHHADS should be considered for patients with unexplained obesity, fever, and hypoventilation, with or without central nervous system symptoms. Early diagnosis and standardized follow-up can improve the prognosis of children with ROHHADS.