Objective:To summarize the clinical characteristics of children with mitochondrial short-chain enoyl-CoA hydratase-1 deficiency (ECHS1D) caused by c.489G>A (p.Pro163=) compound heterozygous variants in the ECHS1 gene, and to explore genotype-phenotype correlations.Methods:A case series study was performed to analyze clinical, biochemical, metabolic, imaging, genetic, treatment and follow-up outcomes of 24 children with ECHS1 gene c.489G>A(p.Pro163=) variant, who were diagnosed in the Department of Neurology, Beijing Children′s Hospital from July 2010 to June 2024. Disease severity was assessed using the Newcastle Paediatric Mitochondrial Disease Scale, and Fisher exact test was applied to compare the improvement rate between valine-restricted and non-restricted groups.Results:These 24 children were all diagnosed after 2022, with a disease duration of 3.35 (1.25, 6.52) years at diagnosis. A total of 8 children initially had negative genetic results, and were finally confirmed by abnormal splicing of ECHS1 gene via skin fibroblast RNA sequencing, with the longest diagnostic time of 14 years. All 24 children presented with Leigh syndrome, including 11 boys and 13 girls, with an onset age of 1.46 (0.96, 2.79) years; 16 children (67%) were mild cases. Common initial symptoms included developmental delay (9 cases) and paroxysmal dystonia (9 cases), followed by developmental regression (3 cases), nystagmus (2 cases), and epilepsy (1 case). Main manifestations were dystonia (18 cases), developmental regression (14 cases), nystagmus (12 cases), developmental delay (11 cases), ataxia (10 cases), vision loss (9 cases), seizures (2 cases), and hearing impairment (1 case). Among 22 children who underwent blood and urine metabolic screening, 21 children (95%) had elevated urinary 2, 3-dihydroxy-2-methylbutyric acid and 19 children (86%) had elevated urinary S-(2-hydroxypropyl) cysteamine. All 24 children had symmetric abnormal signals in bilateral globus pallidus on cranial magnetic resonance imaging, 10 children had isolated globus pallidus involvement, and other common involved sites included caudate nucleus and brainstem (9 cases each), putamen (7 cases), and cerebral white matter (5 cases). At last follow-up, all 24 children survived, with a follow-up duration of 5.40 (2.75, 8.02) years and a maximum age of 17.8 years; 17 children (71%) had varying degrees of clinical improvement. There was no statistical difference in the improvement rate between children with or without valine-restricted diet (12/14 vs. 5/8, P=0.309). A total of 18 pathogenic variants in the ECHS1 gene were identified among 24 children, 13 of which were distributed in exons 7 and 8; those carrying c.308T>C, c.523G>A, c.796A>G, and c.832G>A variants were mostly severe cases. Conclusions:Children carrying ECHS1 gene c.489G>A(p.Pro163=) compound heterozygous variants face significant diagnostic delay. Clinical awareness of this synonymous variant needs further improvement for timely diagnosis. All these cases present as Leigh syndrome, mostly mild, with no clear genotype-phenotype correlation identified.

Objective:To summarize the long-term efficacy of nicotinamide in treating pediatric early-onset progressive encephalopathy with brain edema and (or) leukoencephalopathy-2 (PEBEL2) caused by NAXD gene variation .Methods:This was a case report conducted from February 2019 to January 2025. The long-term efficacy of nicotinamide was observed by following up a child with PEBEL2 who received the treatment in the Department of Neurology, Beijing Children′s Hospital Affiliated to Capital Medical University. The clinical data included changes in skin lesions, neurological symptoms. The modified Rankin scale (mRS) was used to evaluate the recovery of neurological function.Results:A boy was diagnosed with PEBEL2 caused by NAXD gene variation via genetic testing at Beijing Children′s Hospital Affiliated to Capital Medical University in February 2019, when he was 4 years and 6 months of age. Immediately after diagnosis, nicotinamide treatment was initiated at an initial dose of 100 mg/d, which was increased by 100 mg per week and gradually increased to 500 mg/d; meanwhile, other therapeutic drugs were gradually discontinued. After 1 year and 8 months of treatment, the child′s skin lesions had completely resolved; at the 2-year follow-up, dystonia in both upper limbs and swallowing dysfunction was alleviated significantly; by 2.5-year follow-up, his cognitive function also showed improvement. When the child was treated with 500 mg/d for 3 years, a rash appeared around the mouth. After the dose was reduced to 250 mg/d, the rash resolved, and the dose of 250 mg/d was maintained until the last follow-up. At the last follow-up in January 2025, the child was 10 years and 5 months of age. His mRS score decreased from 5 (before treatment) to 4. During the 6-year of continuous nicotinamide treatment, the child′s condition remained stable without progression. Drug-related skin rashes occurred, but no severe drug-related adverse reactions were observed.Conclusions:PEBEL2 is a treatable mitochondrial disease. Nicotinamide treatment can effectively improve skin lesions and neurological symptoms in PEBEL2 patients, and the long-term administration demonstrates a favorable safety profile.

Objective:To summarize the clinical characteristics of children with mitochondrial short-chain enoyl-CoA hydratase-1 deficiency (ECHS1D) caused by c.489G>A (p.Pro163=) compound heterozygous variants in the ECHS1 gene, and to explore genotype-phenotype correlations.Methods:A case series study was performed to analyze clinical, biochemical, metabolic, imaging, genetic, treatment and follow-up outcomes of 24 children with ECHS1 gene c.489G>A(p.Pro163=) variant, who were diagnosed in the Department of Neurology, Beijing Children′s Hospital from July 2010 to June 2024. Disease severity was assessed using the Newcastle Paediatric Mitochondrial Disease Scale, and Fisher exact test was applied to compare the improvement rate between valine-restricted and non-restricted groups.Results:These 24 children were all diagnosed after 2022, with a disease duration of 3.35 (1.25, 6.52) years at diagnosis. A total of 8 children initially had negative genetic results, and were finally confirmed by abnormal splicing of ECHS1 gene via skin fibroblast RNA sequencing, with the longest diagnostic time of 14 years. All 24 children presented with Leigh syndrome, including 11 boys and 13 girls, with an onset age of 1.46 (0.96, 2.79) years; 16 children (67%) were mild cases. Common initial symptoms included developmental delay (9 cases) and paroxysmal dystonia (9 cases), followed by developmental regression (3 cases), nystagmus (2 cases), and epilepsy (1 case). Main manifestations were dystonia (18 cases), developmental regression (14 cases), nystagmus (12 cases), developmental delay (11 cases), ataxia (10 cases), vision loss (9 cases), seizures (2 cases), and hearing impairment (1 case). Among 22 children who underwent blood and urine metabolic screening, 21 children (95%) had elevated urinary 2, 3-dihydroxy-2-methylbutyric acid and 19 children (86%) had elevated urinary S-(2-hydroxypropyl) cysteamine. All 24 children had symmetric abnormal signals in bilateral globus pallidus on cranial magnetic resonance imaging, 10 children had isolated globus pallidus involvement, and other common involved sites included caudate nucleus and brainstem (9 cases each), putamen (7 cases), and cerebral white matter (5 cases). At last follow-up, all 24 children survived, with a follow-up duration of 5.40 (2.75, 8.02) years and a maximum age of 17.8 years; 17 children (71%) had varying degrees of clinical improvement. There was no statistical difference in the improvement rate between children with or without valine-restricted diet (12/14 vs. 5/8, P=0.309). A total of 18 pathogenic variants in the ECHS1 gene were identified among 24 children, 13 of which were distributed in exons 7 and 8; those carrying c.308T>C, c.523G>A, c.796A>G, and c.832G>A variants were mostly severe cases. Conclusions:Children carrying ECHS1 gene c.489G>A(p.Pro163=) compound heterozygous variants face significant diagnostic delay. Clinical awareness of this synonymous variant needs further improvement for timely diagnosis. All these cases present as Leigh syndrome, mostly mild, with no clear genotype-phenotype correlation identified.

Objective:To summarize the long-term efficacy of nicotinamide in treating pediatric early-onset progressive encephalopathy with brain edema and (or) leukoencephalopathy-2 (PEBEL2) caused by NAXD gene variation .Methods:This was a case report conducted from February 2019 to January 2025. The long-term efficacy of nicotinamide was observed by following up a child with PEBEL2 who received the treatment in the Department of Neurology, Beijing Children′s Hospital Affiliated to Capital Medical University. The clinical data included changes in skin lesions, neurological symptoms. The modified Rankin scale (mRS) was used to evaluate the recovery of neurological function.Results:A boy was diagnosed with PEBEL2 caused by NAXD gene variation via genetic testing at Beijing Children′s Hospital Affiliated to Capital Medical University in February 2019, when he was 4 years and 6 months of age. Immediately after diagnosis, nicotinamide treatment was initiated at an initial dose of 100 mg/d, which was increased by 100 mg per week and gradually increased to 500 mg/d; meanwhile, other therapeutic drugs were gradually discontinued. After 1 year and 8 months of treatment, the child′s skin lesions had completely resolved; at the 2-year follow-up, dystonia in both upper limbs and swallowing dysfunction was alleviated significantly; by 2.5-year follow-up, his cognitive function also showed improvement. When the child was treated with 500 mg/d for 3 years, a rash appeared around the mouth. After the dose was reduced to 250 mg/d, the rash resolved, and the dose of 250 mg/d was maintained until the last follow-up. At the last follow-up in January 2025, the child was 10 years and 5 months of age. His mRS score decreased from 5 (before treatment) to 4. During the 6-year of continuous nicotinamide treatment, the child′s condition remained stable without progression. Drug-related skin rashes occurred, but no severe drug-related adverse reactions were observed.Conclusions:PEBEL2 is a treatable mitochondrial disease. Nicotinamide treatment can effectively improve skin lesions and neurological symptoms in PEBEL2 patients, and the long-term administration demonstrates a favorable safety profile.

Tetrandrine(TET),a natural bisbenzyl isoquinoline alkaloid extracted from Stephania tetrandra S.Moore,has diverse pharmacological effects.However,its effects on melanoma remain unclear.Cellular prolif-eration assays,multi-omics analyses,and xenograft models were used to determine the effect of TET on melanoma.The direct target of TET was identified using biotin-TET pull-down liquid chromatograph-mass spectrometry(LC-MS),cellular thermal shift assays,and isothermal titration calorimetry(ITC)analysis.Our findings revealed that TET treatment induced robust cellular autophagy depending on activating transcription factor 6(ATF6)-mediated endoplasmic reticulum(ER)stress.Simultaneously,it hindered autophagic flux by inducing cytoskeletal protein depolymerization in melanoma cells.TET treatment resulted in excessive accumulation of reactive oxygen species(ROS)and simultaneously triggered mitophagy.Sirtuin 5(SIRT5)was ultimately found to be a direct target of TET.Mechanistically,TET led to the degradation of SIRT5 via the ubiquitin(Ub)-26S proteasome system.SIRT5 knockdown induced ROS accumulation,whereas SIRT5 overexpression attenuated the TET-induced ROS accumula-tion and autophagy.Importantly,TET exhibited anti-cancer effects in xenograft models depending on SIRT5 expression.This study highlights the potential of TET as an antimelanoma agent that targets SIRT5.These findings provide a promising avenue for the use of TET in melanoma treatment and underscore its potential as a therapeutic candidate.

Objective:To summarize the clinical characteristics of children carrying the m.8344A>G variant of MT-TK gene.Methods:A case series study was conducted to retrospectively collect data of 22 children with mitochondrial disease caused by MT-TK gene m.8344A>G variation who were treated at the Department of Neurology of Beijing Children′s Hospital of Capital Medical University from January 2012 to January 2024. Their clinical data, laboratory tests, muscle pathology, genetic testing, and the follow-up results were analyzed. Pearson correlation analysis was used for correlation analysis.Results:Among the 22 children, there were 13 boys and 9 girls. The age of onset was 5.00 (2.75, 9.00) years. Fifteen children had myoclonic epilepsy with ragged-red fibers (MERRF), 3 had Leigh syndrome (LS), and 4 had LS-MERRF overlap syndrome (LS-MERRF). Myoclonus presented and worsened progressively in all 15 MERRF children, with 10 as the initial symptom and 5 developing progressively during the disease course. Myoclonus was predominantly focal, worsening with fine motor tasks or stress. Electroencephalogram monitoring in the 15 MERRF children revealed myoclonic seizures in 10 children, with 6 classified as myoclonic epilepsy, and 4 as subcortical myoclonus. Two children had generalized myoclonic seizures, and 1 each had absence seizures and generalized seizures. Twelve children had cerebellar ataxia, 10 children exhibited exercise intolerance, and 8 children had muscle weakness. Magnetic resonance imaging (MRI) revealed periventricular white matter involvement in 1 child and bilateral hippocampal involvement in 1 child, likely due to frequent seizures. All 3 children with LS exhibited developmental regressions, accompanied with 2 symptoms include cerebellar ataxia, muscle weakness, and dysphagia. The clinical manifestations of 4 LS-MERRF overlap children presented with combined features of MERRF and LS. Cranial MRI in the 7 LS and LS-MERRF children showed brainstem involvement (all affecting the midbrain) in 6 children and basal ganglia involvement in 4 children. Among the 22 children, 12 had m.8344A>G variant levels >90%, 3 had >80%-90%, 4 had >70%-80%, and 3 had >60%-70%. Higher variant level correlated with the LS phenotype and earlier onset age ( r=0.47, -0.50; P=0.018 and 0.029, respectively). Sanger sequencing in 19 mothers revealed m.8344A>G variations in 18, with 4 showing exercise intolerance. Follow-up of 13 children on antimyoclonic treatment showed>75% reduction in seizures with levetiracetam monotherapy in 2 children, with combination therapy required in others. Most achieved >50% seizures reduction within 2 years, but the effectiveness declined with disease progression. Conclusions:The m.8344A>G variant is rare, with MERRF being the most common phenotype, while LS and LS-MERRF are less common. Children with higher ratio of the m.8344A>G variant are more likely to present LS phenotype. Myoclonus, primarily focal, is a key feature, with levetiracetam as the first-line treatment and benzodiazepines recommended for refractory cases.

Objective To investigate the expression and relationship of canonical transient receptor potential channel-3 (TRPC3) and brain-derived neurotrophic factor (BDNF) in the hippocampus of a rat model of Alzheimer's disease (AD). Methods SD rats were randomly divided into PBS, AD, and AD+BDNF experimental groups. AD models were generated by intracerebroventricular injection ofβ-amyloid protein (Aβ1-42). BDNF was injected via the lateral ventricle catheter after 14 days. The Morris water maze test was used to assess the spatial learning and memory ability of the rats. The expression of TRPC3 and BDNF mRNA and protein in the hippocampus were detected by RT-PCR and Western blotting, respectively. Results The Morris water maze test showed that the escape latencies of the fifth day in the AD group were longer than those in the PBS group (P ＜ 0. 05). The escape latencies in the AD+BDNF group were shorter than those in the AD group (P ＜ 0. 05). RT-PCR and Western blotting results showed that the expression of both TRPC3 and BDNF were reduced in the AD group compared with the PBS group (P ＜ 0. 05). TRPC3 expression was increased in the AD+BDNF group compared with the AD group (P ＜ 0. 05). Conclusion The expression of BDNF and TRPC3 is decreased in the hippocampus of AD rats. An exogenous BDNF injection appears to improve the spatial learning and memory of AD rats that are impaired by a Aβ1-42 injection, possibly via TRPC3 upregulation, and may play a protective role in neurons.

Objective To evaluate the clinical value of speckle tracking imaging in the measurement of two-dimensional strain in patients with myocardial infarction. Methods High frame rate two-dimensional echocardiography were performed in 30 healthy subjects,21patients with anterior myocardial infarction and 15 patients with inferior myocardial infarction. Longitudinal strain (LS), radial velocity (Vs), regional shortening fraction (RFS),radial strain (RS) were measured in the apical two-chamber view and short-axis view(the level of papillary muscle) using two-dimensional strain software. Results Compared with healthy subjects, LS, Vs, RFS, RS decreased in the segments with infarction(P<0.05). LS, Vs, RFS, RS of the two myocardial infarction groups had partly differences(P<0.05). Conclusions Regional wall motion of left ventricle in patients with myocardial infarction can be evaluated accurately with speckle tracking imaging.