Neurological outcome in long-chain hydroxy fatty acid oxidation disorders.

OBJECTIVE: This study aims to elucidate the long-term benefit of newborn screening (NBS) for individuals with long-chain 3-hydroxy-acyl-CoA dehydrogenase (LCHAD) and mitochondrial trifunctional protein (MTP) deficiency, inherited metabolic diseases included in NBS programs worldwide. METHODS: German national multicenter study of individuals with confirmed LCHAD/MTP deficiency identified by NBS between 1999 and 2020 or selective metabolic screening. Analyses focused on NBS results, confirmatory diagnostics, and long-term clinical outcomes. RESULTS: Sixty-seven individuals with LCHAD/MTP deficiency were included in the study, thereof 54 identified by NBS. All screened individuals with LCHAD deficiency survived, but four with MTP deficiency (14.8%) died during the study period. Despite NBS and early treatment neonatal decompensations (28%), symptomatic disease course (94%), later metabolic decompensations (80%), cardiomyopathy (28%), myopathy (82%), hepatopathy (32%), retinopathy (17%), and/or neuropathy (22%) occurred. Hospitalization rates were high (up to a mean of 2.4 times/year). Disease courses in screened individuals with LCHAD and MTP deficiency were similar except for neuropathy, occurring earlier in individuals with MTP deficiency (median 3.9 vs. 11.4 years; p = 0.0447). Achievement of dietary goals decreased with age, from 75% in the first year of life to 12% at age 10, and consensus group recommendations on dietary management were often not achieved. INTERPRETATION: While NBS and early treatment result in improved (neonatal) survival, they cannot reliably prevent long-term morbidity in screened individuals with LCHAD/MTP deficiency, highlighting the urgent need of better therapeutic strategies and the development of disease course-altering treatment.

Different Lipid Signature in Fibroblasts of Long-Chain Fatty Acid Oxidation Disorders.

Long-chain fatty acid oxidation disorders (lc-FAOD) are a group of diseases affecting the degradation of long-chain fatty acids. In order to investigate the disease specific alterations of the cellular lipidome, we performed undirected lipidomics in fibroblasts from patients with carnitine palmitoyltransferase II, very long-chain acyl-CoA dehydrogenase, and long-chain 3-hydroxyacyl-CoA dehydrogenase. We demonstrate a deep remodeling of mitochondrial cardiolipins. The aberrant phosphatidylcholine/phosphatidylethanolamine ratio and the increased content of plasmalogens and of lysophospholipids support the theory of an inflammatory phenotype in lc-FAOD. Moreover, we describe increased ratios of sphingomyelin/ceramide and sphingomyelin/hexosylceramide in LCHAD deficiency which may contribute to the neuropathic phenotype of LCHADD/mitochondrial trifunctional protein deficiency.

Long-chain 3-hydroxyacyl-CoA dehydrogenase (LCHAD) deficiency and progressive retinopathy: one case report followed by ERGs, VEPs, EOG over a 17-year period.

BACKGROUND: LCHAD (long-chain 3-hydroxyacyl-CoA dehydrogenase) deficiency is a rare genetic disorder of mitochondrial long-chain fatty acid oxidation inherited as a recessive trait. Affected patients can present with hypoglycaemia, rhabdomyolysis and cardiomyopathy. About half of the patients may suffer from retinopathy. CASE REPORT: A 19-year-old girl was diagnosed as suffering from LCHAD deficiency with recurrent rhabdomyolysis episodes at the age of 7 months by an inaugural coma with hypoglycaemia and hepatomegaly. Appropriate dietary management with carnitine supplementation was initiated. Retinopathy was diagnosed at age two. Ophthalmological assessments including visual acuity, visual field, OCT, flash ERGs, P-ERG, flash VEPs and EOG recordings were conducted over a 17-year period. RESULTS: Visual acuity was decreased. Fundi showed a progressive retinopathy and chorioretinopathy. Photophobia was noticed 2 years before the decrease in photopic-ERG amplitude with normal scotopic-ERGs. Scotopic-ERG amplitude decreased 10 years after the decrease in photopic-ERG amplitude. No EOG light rise was observed. Flash VEPs remained normal. These results suggest that the cone system dysfunction occurs largely prior to the rod system dysfunction with a relative preservation of the macula function. COMMENTS: This dysfunction of cones prior to the dysfunction of rods was not reported previously. This could be related to mitochondrial energy failure in cones as cones are greater consumers of ATP than rods. This hypothesis needs to be further confirmed as other long-chain fatty oxidation defective patients (VLCAD and CPT2 deficiencies) do not exhibit retinopathy.

Retained visual function in a subset of patients with long-chain 3-hydroxyacyl-CoA dehydrogenase deficiency (LCHADD).

Introduction: LCHADD causes retinopathy associated with low vision, visual field defects, nyctalopia and myopia. We report a retrospective long-term single-center study of 6 LCHADD patients trying to clarify if early diagnosis has an impact on the course and outcome of chorioretinal degeneration. Methods: Long-term follow-up of visual acuity and staging of chorioretinal degeneration by fundus photography, optical coherence tomography (OCT) and autofluorescence (AF) in all six patients. Three patients (2 m/1 f; age 8-14.8 years) were diagnosed by newborn screening, a single patient early within the first year of life and treated promptly while the other two (1 m/1 f; age 23-24 years) were diagnosed later after developing symptoms. All carried HADHA variants; five were homozygous for the common p.E510Q variant, in one from the symptomatically diagnosed group p.[E510Q]; [R291*] was detected. Results: All patients showed retinal alterations, but early diagnosis was associated with a milder phenotype and a longer preservation of visual function. Among symptomatic patients, only one showed mild retinal involvement at the time of diagnosis. Conclusion: Despite the small number our study suggests that early diagnosis does not prevent retinopathy but might contribute to a milder phenotype with retained good visual acuity over time. OCT and AF are reliable non-invasive diagnostic tools to estimate the progression of early-stage retinal changes in LCHADD patients.

Effects of fasting, feeding and exercise on plasma acylcarnitines among subjects with CPT2D, VLCADD and LCHADD/TFPD.

BACKGROUND: The plasma acylcarnitine profile is frequently used as a biochemical assessment for follow-up in diagnosed patients with fatty acid oxidation disorders (FAODs). Disease specific acylcarnitine species are elevated during metabolic decompensation but there is clinical and biochemical heterogeneity among patients and limited data on the utility of an acylcarnitine profile for routine clinical monitoring. METHODS: We evaluated plasma acylcarnitine profiles from 30 diagnosed patients with long-chain FAODs (carnitine palmitoyltransferase-2 (CPT2), very long-chain acyl-CoA dehydrogenase (VLCAD), and long-chain 3-hydroxy acyl-CoA dehydrogenase or mitochondrial trifunctional protein (LCHAD/TFP) deficiencies) collected after an overnight fast, after feeding a controlled low-fat diet, and before and after moderate exercise. Our purpose was to describe the variability in this biomarker and how various physiologic states effect the acylcarnitine concentrations in circulation. RESULTS: Disease specific acylcarnitine species were higher after an overnight fast and decreased by approximately 60% two hours after a controlled breakfast meal. Moderate-intensity exercise increased the acylcarnitine species but it varied by diagnosis. When analyzed for a genotype/phenotype correlation, the presence of the common LCHADD mutation (c.1528G > C) was associated with higher levels of 3-hydroxyacylcarnitines than in patients with other mutations. CONCLUSIONS: We found that feeding consistently suppressed and that moderate intensity exercise increased disease specific acylcarnitine species, but the response to exercise was highly variable across subjects and diagnoses. The clinical utility of routine plasma acylcarnitine analysis for outpatient treatment monitoring remains questionable; however, if acylcarnitine profiles are measured in the clinical setting, standardized procedures are required for sample collection to be of value.

Evaluation of earlier versus later dietary management in long-chain 3-hydroxyacyl-CoA dehydrogenase or mitochondrial trifunctional protein deficiency: a systematic review.

BACKGROUND: Mitochondrial trifunctional protein (MTP) and long-chain 3-hydroxyacyl-CoA dehydrogenase (LCHAD) deficiencies are rare fatty acid ß-oxidation disorders. Without dietary management the conditions are life-threatening. We conducted a systematic review to investigate whether pre-symptomatic dietary management following newborn screening provides better outcomes than treatment following symptomatic detection. METHODS: We searched Web of Science, Medline, Pre-Medline, Embase and the Cochrane Library up to 23rd April 2018. Two reviewers independently screened titles, abstracts and full texts for eligibility and quality appraised the studies. Data extraction was performed by one reviewer and checked by another. RESULTS: We included 13 articles out of 7483 unique records. The 13 articles reported on 11 patient groups, including 174 people with LCHAD deficiency, 18 people with MTP deficiency and 12 people with undifferentiated LCHAD/MTP deficiency. Study quality was moderate to weak in all studies. Included studies suggested fewer heart and liver problems in screen-detected patients, but inconsistent results for mortality. Follow up analyses compared long-term outcomes of (1) pre-symptomatically versus symptomatically treated patients, (2) screened versus unscreened patients, and (3) asymptomatic screen-detected, symptomatic screen-detected, and clinically diagnosed patients in each study. For follow up analyses 1 and 2, we found few statistically significant differences in the long-term outcomes. For follow up analysis 3 we found a significant difference for only one comparison, in the incidence of cardiomyopathy between the three groups. CONCLUSIONS: There is some evidence that dietary management following screen-detection might be associated with a lower incidence of some LCHAD and MTP deficiency-related complications. However, the evidence base is limited by small study sizes, quality issues and risk of confounding. An internationally collaborative research effort is needed to fully examine the risks and the benefits to pre-emptive dietary management with particular attention paid to disease severity and treatment group.

Blood cytokine patterns suggest a modest inflammation phenotype in subjects with long-chain fatty acid oxidation disorders.

Excessive cellular accumulation or exposure to lipids such as long-chain acylcarnitines (LCACs), ceramides, and others is implicated in cell stress and inflammation. Such a situation might manifest when there is a significant mismatch between long-chain fatty acid (LCFA) availability versus storage and oxidative utilization; for example, in cardiac ischemia, increased LCACs may contribute to tissue cell stress and infarct damage. Perturbed LCFAß-oxidation is also seen in fatty acid oxidation disorders (FAODs). FAODs typically manifest with fasting- or stress-induced symptoms, and patients can manage many symptoms through control of diet and physical activity. However, episodic clinical events involving cardiac and skeletal muscle myopathies are common and can present without an obvious molecular trigger. We have speculated that systemic or tissue-specific lipotoxicity and activation of inflammation pathways contribute to long-chain FAOD pathophysiology. With this in mind, we characterized inflammatory phenotype (14 blood plasma cytokines) in resting, overnight-fasted (~10 h), or exercise-challenged subjects with clinically well-controlled long-chain FAODs (n = 12; 10 long-chain 3-hydroxyacyl-CoA dehydrogenase [LCHAD]; 2 carnitine palmitoyltransferase 2 [CPT2]) compared to healthy controls (n = 12). Across experimental conditions, concentrations of three cytokines were modestly but significantly increased in FAOD (IFNγ, IL-8, and MDC), and plasma levels of IL-10 (considered an inflammation-dampening cytokine) were significantly decreased. These novel results indicate that while asymptomatic FAOD patients do not display gross body-wide inflammation even after moderate exercise, ß-oxidation deficiencies might be associated with chronic and subtle activation of "sterile inflammation." Further studies are warranted to determine if inflammation is more apparent in poorly controlled long-chain FAOD or when long-chain FAOD-associated symptoms are present.

RETINAL PHENOTYPE IN A CASE OF LCHAD/TFP DEFICIENCY WITH LATE-STAGE DIAGNOSIS.

PURPOSE: To report the retinal phenotype of a rare case of long-chain 3-hydroxyacyl-CoA dehydrogenase (LCHAD)/trifunctional protein (TFP) deficiency diagnosed in his late 40s with ocular findings of diffuse chorioretinal atrophy and bilateral retinoschisis. METHODS: An acylcarnitine profile assay revealed LCHAD/TFP deficiency in a 45-year-old man with a history of high myopia, bilateral decreased vision, episodic rhabdomyolysis, and peripheral neuropathy. Ocular findings were evaluated with spectral domain optical coherence tomography (Spectralis OCT; Heidelberg Engineering, Heidelberg, Germany) and color fundus photography. RESULTS: Spectral domain optical coherence tomography revealed severe bilateral macular retinoschisis. Subretinal fibrosis was noted in the left temporal macula with an associated lamellar macular hole. Fundus photographs demonstrated diffuse, symmetric chorioretinal atrophy characteristic of end-stage retinopathy, as previously reported in younger patients. Myopic staphylomas were evident in the posterior pole of both eyes. A trial of topical dorzolamide for 3 months resulted in no change in the retinal profile. CONCLUSION: We report the retinal phenotype of a patient with LCHAD/TFP deficiency diagnosed later in life. To date, this is the oldest patient reported with LCHAD/TFP-associated retinopathy. Macular retinoschisis may represent a feature of the end-stage retinopathy due to the progressive myopia. The diagnosis of LCHAD/TFP deficiency should be considered in adult patients with a history rhabdomyolysis, neuropathy, and retinopathy, as they would not have undergone routine newborn screening before the late 90s.

Fatal pitfalls in newborn screening for mitochondrial trifunctional protein (MTP)/long-chain 3-Hydroxyacyl-CoA dehydrogenase (LCHAD) deficiency.

BACKGROUND: Mitochondrial trifunctional protein (MTP) and long-chain 3-hydroxyacyl-CoA dehydrogenase (LCHAD) deficiency are long-chain fatty acid oxidation disorders with particularly high morbidity and mortality. Outcome can be favorable if diagnosed in time, prompting the implementation in newborn screening programs. Sporadic cases missed by the initial screening sample have been reported. However, little is known on pitfalls during confirmatory testing resulting in fatal misconception of the diagnosis. RESULTS: We report a series of three patients with MTP and LCHAD deficiency, in whom diagnosis was missed by newborn screening, resulting in life-threatening metabolic decompensations within the first half year of life. Two of the patients showed elevated concentrations of primary markers C16-OH and C18:1-OH but were missed by confirmatory testing performed by the maternity clinic. A metabolic center was not consulted. Confirmatory testing consisted of analyses of acylcarnitines in blood and organic acids in urine, the finding of normal excretion of organic acids led to rejection and underestimation of the diagnosis, respectively. The third patient, a preterm infant, was not identified in the initial screening sample due to only moderate elevations of C16-OH and C18:1-OH and normal secondary markers and analyte ratios. CONCLUSION: Our observations highlight limitations of newborn screening for MTP/LCHAD deficiency. They confirm that analyses of acylcarnitines in blood and organic acids in urine alone are not suitable for confirmatory testing and molecular or functional analysis is crucial in diagnosing MTP/LCHAD deficiency. Mild elevations of primary biomarkers in premature infants need to trigger confirmatory testing. Our report underscores the essential role of specialized centers in confirming or ruling out diagnoses in suspicious screening results.

[Regulation of pravastatin on long-chain fatty acid oxidative enzyme in pre-eclampsia-like mouse model].

Objective: To investigate the modulation of long-chain 3-hydroxyacyl-CoA dehydrogenase (LCHAD) expression by pravastatin in pre-eclampsia-like mouse model. Methods: C57BL/6J mice were randomly injected with N-nitro-L-arginine methyl ester (L-NAME) as pre-eclampsia-like model group (PE) or saline as normal pregnancy control group (Con) respectively, from gestational the 7th to 18th day. For each group, pravastatin (PE+Pra, Con+Pra group) or saline (PE+N, Con+N Group) was given from the 8th to 18th day of gestation, respectively. Liver and placenta of pregnant mice were collected on gestational day 18. The LCHAD protein expression and mRNA levels of liver and placenta were detected through western blot, immunohistochemistry and real-time quantitative PCR. Results: (1) The average arterial pressure of pregnant mice increased gradually from the 8th to 18th day in PE+N group, but decreased in PE+Pra group from gestational 10th day, 24 hour urinary protein levels in PE+N group [(1 494 ± 201) µg] were significantly higher than that in Con+N group [(935±128) µg, P<0.01], and also higher than that in PE+Pra group [(981±116) µg, P<0.01].(2) The results of western blot: the expression of LCHAD was significantly lower in PE+N group (liver: 0.64±0.11, placenta: 0.48±0.06) than that in Con+N group (liver: 1.06±0.10, placenta: 0.60±0.10), and lower than that in PE+Pra group (liver: 0.99±0.04, placenta: 0.60±0.08; all P<0.01).(3)The results of real-time quantitative PCR: the levels of LCHAD mRNA in liver and placenta in PE+N group (liver: 0.621±0.128, placenta: 0.646±0.129) were significantly decreased compared with Con+N group (liver: 1.007±0.130, placenta: 1.004±0.103; all P<0.01), but there was no significant difference between PE+Pra group (liver: 0.693±0.678, placenta: 0.662±0.183; P>0.05). (4) LCHAD protein was expressed widely and evenly in liver. The expression in placental cytotrophoblast and syncytial trophoblast cells located in outer layer of villous in labyrinth layer was the most. The expression of LCHAD was significantly lower in PE+N group (liver: 0.062±0.016, placenta: 0.147±0.018) than that in Con+N group (liver: 0.126±0.013, placenta: 0.183±0.024), and lower than that in PE+Pra group (liver: 0.111±0.017, placenta: 0.174±0.027; all P<0.05). Conclusion: Pravastatin could upregulate the LCHAD protein expression of liver and placenta in the pre-eclampsia-like mouse, which may be a mechanism to improve the clinical manifestations of pre-eclampsia.

Two Fungicides Alter Reproduction of the Small Brown Planthopper Laodelphax striatellus by Influencing Gene and Protein Expression.

Aside from their intended actions, fungicides can drive pest insect outbreaks due to virtually continuous use and pest evolution. Small brown planthopper (SBPH), Laodelphax striatellus, outbreaks occurred recently in many provinces in China, with devastating rice losses. Because exposure to the fungicide jinggangmycin (JGM) increased reproduction of the brown plant hopper, Nilaparvata lugens, via its influence on fatty acid synthase, we posed the hypothesis that JGM and carbendazim (CBM) influence SBPH reproduction via their influence on enzymes involved in other aspects of lipid metabolism. Exposure to the fungicide CBM stimulated SBPH reproduction (egg-laying up by 78%) and to another fungicide, JGM, led to decreased egg-laying (down by 47.3%). These inverse effects are mediated by down-regulated expression of l-3-hydroxyacyl-coenzyme A dehydrogenase (LCHAD) in JGM-treated females and up-regulated expression of hydroxysteroid dehydrogenase-like protein 2-like (HSD) in CBM-treated females. RNAi knockdown of, separately, LCHAD and HSD led to reduced egg-laying (down by 52% for dsLCHAD and by 73% for dsHSD). dsLCHAD, dsHSD, and JGM treatments also led to severely reduced ovarian development in experimental SBPH, with shorted and thinned valvula and lack of egg cells in ovaries. Valvula of CBM-treated females enlarged, with banana-shaped eggs in ovaries. These data strongly support our hypothesis.

Oligo(cis-1,4-isoprene) aldehyde-oxidizing dehydrogenases of the rubber-degrading bacterium Gordonia polyisoprenivorans VH2.

The actinomycete Gordonia polyisoprenivorans strain VH2 is well-known for its ability to efficiently degrade and catabolize natural rubber [poly(cis-1,4-isoprene)]. Recently, a pathway for the catabolism of rubber by strain VH2 was postulated based on genomic data and the analysis of mutants (Hiessl et al. in Appl Environ Microbiol 78:2874-2887, 2012). To further elucidate the degradation pathway of poly(cis-1,4-isoprene), 2-dimensional-polyacrylamide gel electrophoresis was performed. The analysis of the identified protein spots by matrix-assisted laser desorption/ionization-time of flight tandem mass spectrometry confirmed the postulated intracellular pathway suggesting a degradation of rubber via ß-oxidation. In addition, other valuable information on rubber catabolism of G. polyisoprenivorans strain VH2 (e.g. oxidative stress response) was provided. Identified proteins, which were more abundant in cells grown with rubber than in cells grown with propionate, implied a putative long-chain acyl-CoA-dehydrogenase, a 3-ketoacyl-CoA-thiolase, and an aldehyde dehydrogenase. The amino acid sequence of the latter showed a high similarity towards geranial dehydrogenases. The expression of the corresponding gene was upregulated > 10-fold under poly(cis-1,4-isoprene)-degrading conditions. The putative geranial dehydrogenase and a homolog were purified and used for enzyme assays. Deletion mutants for five aldehyde dehydrogenases were generated, and growth with poly(cis-1,4-isoprene) was investigated. While none of the mutants had an altered phenotype regarding growth with poly(cis-1,4-isoprene) as sole carbon and energy source, purified aldehyde dehydrogenases were able to catalyze the oxidation of oligoisoprene aldehydes indicating an involvement in rubber degradation.

Déficit de 3-hidroxiacil-CoA-deshidrogenasa de cadena larga: a propósito de un caso / Long-chain 3-hydroxyacyl-CoA dehydrogenase deficiency: A case report

CASO CLÍNICO: Paciente de 5 años de edad remitido para valoración oftalmológica con el diagnóstico de déficit de 3-hidroxiacil-CoA deshidrogenasa de cadena larga. Presentaba como antecedente la aparición de crisis metabólicas agudas precipitadas por infecciones banales y rabdomiólisis. El examen oftalmoscópico reveló una atrofia coriorretiniana peripapilar y una maculopatía granular difusa. La agudeza visual era de 6/6 en ambos ojos y las pruebas electrofisiológicas normales. DISCUSIÓN: Se realiza una revisión de la bibliografía y los conocimientos recientes de esta enfermedad mediante la descripción de un caso clínico documentando los hallazgos obtenidos mediante autofluorescencia y tomografía de coherencia óptica para mejorar el conocimiento existente sobre ella

CLINICAL CASE: A five-year-old patient, with a diagnosis of long-chain 3-hydroxyacyl-CoA dehydrogenase deficiency, was referred for an ophthalmological examination. He had a history of acute metabolic crises precipitated by intercurrent infections,as well as rhabdomyolysis. The fundoscopic examination revealed a peripapillary chorioretinal atrophy and a diffuse granular appearance of the macular retinal pigment epithelium. Best corrected visual acuity was 6/6 in both eyes, and he had a normal electroretinography test. DISCUSSION: We perform a review of the literature and recent findings in relation to this disease through the description of a clinical case in order to improve the knowledge of this uncommon disorder

[Variation of long-chain 3-hydroxyacyl CoA dehydrogenase DNA methylated modification and correlation with gene mRNA expression of early-onset preeclampsia, HELLP syndrome and antiphospholipid syndrome in trophoblast cells of placenta].

OBJECTIVE: By detecting the DNA methylation and gene expression of long-chain 3-hydroxyacyl CoA dehydrogenase(LCHAD)in trophoblast cells, analyze the correlation of DNA methylation and gene expression in early-onset preeclampsia(EPE), hemolysis, elevated liver enzymes, and low platelets(HELLP)syndrome and antiphospholipid syndrome(APS), to investigate the molecular basis of long-chain fatty acid oxidation changes in different preeclampsia and pathological pregnancy. METHODS: Primary human cytotrophoblast cells and HTR8/Svneo cells were treated with serum from patients with EPE(14 cases), HELLP(12 cases), APS(14 cases), and normal pregnant women(NP, 14 cases). The methylation level of LCHAD gene promoter region through the MassARRAY platform and mRNA expression level by real-time fluorescent quantitative PCR technique were conducted. RESULTS: (1)Cytosine-phosphate-guanine(CpG)sites in human LCHAD DNA promoter region: CpG sites were detected in the range of 558 bp before LCHAD gene transcription start site, the detected CpG sites were 11 sites including 8 single sites and 3 complex sites. The position of these sites were at-984,-960,-899,-853,-811,-796,-774,-727,-615,-595,-579 respectively.(2)The sites of-899,-853,-615 and-595 showed increased methylation level in EPE and HELLP groups. The methylation level at-899,-853 and-615 sites in EPE and HELLP groups were significantly higher than those in NP group(P<0.01). The methylation level at-853 site was higher in EPE group than that in HELLP group(P<0.05). The-595 site showed the unmethylated in EPE, HELLP and APS groups. There were significantly difference between the 3 groups and EPE group(P<0.01).(3)The gene expression of LCHAD mRNA in EPE(0.048±0.005), HELLP(0.045±0.006)and APS(0.044±0.004)groups were significantly lower than NP group(0.076±0.009; P<0.01).(4)The correlation of methylation level and gene expression in all groups: the methylation level at-899,-853,-727,-615 and-579 sites were negatively correlated with gene mRNA expression in EPE group(P<0.05). The methylation level at-899,-853 and-615 sites were negatively correlated with gene mRNA expression in HELLP group(P< 0.05). CONCLUSIONS: The variation of LCHAD DNA methylation of trophoblast cells are found among EPE, HELLP syndrome and APS. The different correlation of LCHAD DNA methylation and gene expression are different in pathological groups. LCHAD DNA methylation of EPE and HELLP syndrome were significantly increased and negatively correlated with LCHAD gene mRNA expression. These results further revealed the molecular basis of long-chain fatty acid oxidation in different preeclampsia and pathological pregnancy.

[Variation of long-chain 3-hydroxyacyl-CoA dehydrogenase DNA methylation in placenta of different preeclampsia-like mouse models].

OBJECTIVE: By detecting the variation of long-chain 3-hydroxyacyl-CoA dehydrogenase (LCHAD) DNA methylation in preeclampsia-like mouse models generated by different ways, to explore the roles of multifactor and multiple pathways in preeclampsia pathogenesis on molecular basis. METHODS: Established preeclampsia-like mouse models in different ways and divided into groups as follows: (1) Nw-nitro-L-arginine-methyl ester (L-NAME) group: wild-type pregnant mouse received subcutaneous injection of L-NAME; (2) lipopolysaccharide (LPS) group: wild-type pregnant mouse received intraperitoneal injection of LPS; (3) apolipoprotein C-III (ApoC3) group: ApoC3 transgenic pregnant mouse with dysregulated lipid metabolism received subcutaneous injection of L-NAME; (4) ß2 glycoprotein I (ß-2GPI) group: wild-type pregnant mouse received subcutaneous injection of ß-2GPI. According to the first injection time (on day 3, 11, 16 respectively), the L-NAME, LPS and ApoC3 groups were further subdivided into: pre-implantation (PI) experimental stage, early gestation (EG) experimental stage, and late gestation (LG) experimental stage. ß-2GPI group was only injected before implantation. LCHAD gene methylation levels in placental were detected in different experimental stage. Normal saline control groups were set within wild-type and ApoC3 transgenic pregnant mice simultaneously. RESULTS: (1) CG sites in LCHAD DNA: 45 CG sites were detected in the range of 728 bp before LCHAD gene transcription start site, the 5, 12, 13, 14, 15, 16, 19, 24, 25, 27, 28, 29, 30, 31, 32, 34, 35, 43 CG sites were complex sites which contained two or more CG sequences, others were single site which contained one CG sequence. The 3, 5, 6, 11, 13, 14, 18, 28 sites in L-NAME, LPS, ApoC3 and ß-2GPI groups showed different high levels of methylation; the 16, 25, 31, 42, 44 sites showed different low levels of methylation; other 32 sites were unmethylated. (2) Comparison of LCHAD gene methylation between different groups: the methylation levels of LCAHD gene at 3, 11, 13, 14, 18 sites in L-NAME, LPS, ApoC3 and ß-2GPI groups were significantly higher than those in the normal saline control group (P < 0.05); and the methylation levels of 42, 44 sites in these groups were significantly lower than those in the normal saline control group (P < 0.05). (3) Methylation of LCHAD gene at the same site between different experimental stages: ① The 3, 11, 18 sites of EG experimental stage was significantly lower than PI and LG experimental stage in L-NAME group (P < 0.05); the 3, 11, 18 sites of PI experimental stage was significantly lower than EG and LG experimental stage in LPS group (P < 0.05); these sites of PI experimental stage was significantly higher than EG and LG experimental stages in ApoC3 group (P < 0.05). ② The methylation of site 5 in L-NAME and LPS groups were significantly higher than that of the normal saline control group (P < 0.05), and the LG experimental stages were significantly higher than other stages, but in ApoC3 group, only PI and EG stages were significantly higher than the normal saline control group (P < 0.05). ③ At site 6 in L-NAME group which showed high methylation level was significantly higher than the same site in other groups which showed low methylation level (P < 0.05). ④ At 13, 14 sites, earlier preeclampsia onset caused a lower methylation level in L-NAME group, but PI experimental stage was significantly higher than EG and LG experimental stages in LPS group (P < 0.05), EG experimental stage was significantly higher than PI and LG experimental stages in ApoC3 group (P < 0.05). ⑤ At site 28, earlier preeclampsia onset caused a higher methylation level in L-NAME group, but PI experimental stage was significantly lower than EG and LG experimental stages in LPS group (P < 0.05), EG experimental stage was significantly higher than PI and LG experimental stages in ApoC3 group (P < 0.05). ⑥ The 16, 25, 31 sites in ApoC3 group were significantly higher than other groups (P < 0.05). ⑦ At site 42 in ß-2GPI group was unmethylated, but it in other groups showed low methylation level, the methylation level of site 42 in ß-2GPI group was significantly lower than that in other groups (P < 0.05). CONCLUSIONS: The methylation of 6 and 42 CG sites may be related to LCHAD gene expression in placenta of L-NAME and ß-2GPI induced preeclampsia-like models respectively; LCHAD gene expression and DNA methylation may not have obvious correlation in LPS and ApoC3 induced preeclampsia-like models. Differences exist in LCHAD DNA methylation in preeclampsia-like models generated by different ways, revealed a molecular basis to expand our understanding of the multi-factorial pathogenesis of preeclampsia.

[Study on the methylation of LCHAD gene promoter region in mitochondria of trophoblast cells incubated with long-chain fatty acids].

OBJECTIVE: To explore the methylation level of long-chain 3-hydroxyacyl-CoA dehydrogenase (LCHAD) gene promoter region in mitochondria of trophoblasts incubated with long-chain fatty acids and the time-effect of methylation modification. METHODS: Primary human trophoblast cells and HTR8/Svneo cells were incubated with free fatty acids of various lengths. Long-chain free fatty acids (LC-FFA) was experimental group, short-chain fatty acids (SC-FFA) and medium-chain fatty acids (MC-FFA) were control groups, and blank control was without free fatty acid. Collecting cells and extract DNA at 24, 48 and 72 h incubation respectively. Predicted CpG island location access to 2 000 bp DNA sequences upstream of the transcription start site of LCHAD gene. We designed methylation detection sites and primer originally. Methylation of CpG sites in LCHAD gene promoter region were detected by MassARRAY and analyzed statistically. RESULTS: (1) We detected methylation of 65% (11/17) CpG sites, including 8 single sites and 3 composite sites, in ampliconic sequences. These CpG sites were at positions: -984, -960, -899, -853, -811, -796, -774, -727, -615, -595, -579, respectively. In different groups methylation level and changes of every site showed differences with the most significant changes at -899 site. (2) Methylation of CpG island in LCHAD gene promoter region: ① Methylation of CpG island in LC-FFA and MC-FFA groups showed rising trend with the time: Methylation level of LC-FFA group at 72 h (0.55±0.08) was significantly higher than that of 48 h (0.35±0.12) and 24 h (0.31±0.04) (P<0.05). Methylation level of MC-FFA group at 72 h (0.44±0.05) was significantly higher than that of 24 h (0.31±0.04) (P<0.05). ② Methylation of CpG island in LCHAD gene promoter region in different groups at different times: Methylation level of LC-FFA group at 72 h was significantly higher than that of the other two groups at 72, 48 and 24 h (P<0.05). (3) Methylation of 11 CpG sites in LCHAD gene promoter region in different groups at 72 h: Methylation level of -899 site in LC-FFA and MC-FFA groups were significantly higher than that of other sites (P<0.05). (4) Methylation level of -899 site in LCHAD gene promoter region in LC-FFA group showed rising trend with the time: (72 h (0.34±0.15), 48 h (0.14±0.05) and 24 h (0.10±0.02), P<0.05). Methylation level of LC-FFA group at 72 h was significantly higher than that of the other two groups at 72, 48 and 24 h (P<0.05). CONCLUSIONS: Methylation modification effect on LCHAD gene promoter region in trophoblast cells incubated with long-chain fatty acids is more significant than with medium-chain and short-chain fatty acids and shows obvious time-effect as incubation time prolonged. The changes at -899 site dominate the degree of methylation in LCHAD gene promoter region.

Deregulation of mitochondrial functions provoked by long-chain fatty acid accumulating in long-chain 3-hydroxyacyl-CoA dehydrogenase and mitochondrial permeability transition deficiencies in rat heart--mitochondrial permeability transition pore opening as a potential contributing pathomechanism of cardiac alterations in these disorders.

Mitochondrial trifunctional protein and long-chain 3-hydroxyacyl-CoA dehydrogenase deficiencies are fatty acid oxidation disorders biochemically characterized by tissue accumulation of long-chain fatty acids and derivatives, including the monocarboxylic long-chain 3-hydroxy fatty acids (LCHFAs) 3-hydroxytetradecanoic acid (3HTA) and 3-hydroxypalmitic acid (3HPA). Patients commonly present severe cardiomyopathy for which the pathogenesis is still poorly established. We investigated the effects of 3HTA and 3HPA, the major metabolites accumulating in these disorders, on important parameters of mitochondrial homeostasis in Ca(2+) -loaded heart mitochondria. 3HTA and 3HPA significantly decreased mitochondrial membrane potential, the matrix NAD(P)H pool and Ca(2+) retention capacity, and also induced mitochondrial swelling. These fatty acids also provoked a marked decrease of ATP production reflecting severe energy dysfunction. Furthermore, 3HTA-induced mitochondrial alterations were completely prevented by the classical mitochondrial permeability transition (mPT) inhibitors cyclosporin A and ADP, as well as by ruthenium red, a Ca(2+) uptake blocker, indicating that LCHFAs induced Ca(2+)-dependent mPT pore opening. Milder effects only achieved at higher doses of LCHFAs were observed in brain mitochondria, implying a higher vulnerability of heart to these fatty acids. By contrast, 3HTA and docosanoic acids did not change mitochondrial homeostasis, indicating selective effects for monocarboxylic LCHFAs. The present data indicate that the major LCHFAs accumulating in mitochondrial trifunctional protein and long-chain 3-hydroxyacyl-CoA dehydrogenase deficiencies induce mPT pore opening, compromising Ca(2+) homeostasis and oxidative phosphorylation more intensely in the heart. It is proposed that these pathomechanisms may contribute at least in part to the severe cardiac alterations characteristic of patients affected by these diseases.

Nickel inhibits mitochondrial fatty acid oxidation.

Nickel exposure is associated with changes in cellular energy metabolism which may contribute to its carcinogenic properties. Here, we demonstrate that nickel strongly represses mitochondrial fatty acid oxidation-the pathway by which fatty acids are catabolized for energy-in both primary human lung fibroblasts and mouse embryonic fibroblasts. At the concentrations used, nickel suppresses fatty acid oxidation without globally suppressing mitochondrial function as evidenced by increased glucose oxidation to CO2. Pre-treatment with l-carnitine, previously shown to prevent nickel-induced mitochondrial dysfunction in neuroblastoma cells, did not prevent the inhibition of fatty acid oxidation. The effect of nickel on fatty acid oxidation occurred only with prolonged exposure (>5 h), suggesting that direct inhibition of the active sites of metabolic enzymes is not the mechanism of action. Nickel is a known hypoxia-mimetic that activates hypoxia inducible factor-1α (HIF1α). Nickel-induced inhibition of fatty acid oxidation was blunted in HIF1α knockout fibroblasts, implicating HIF1α as one contributor to the mechanism. Additionally, nickel down-regulated the protein levels of the key fatty acid oxidation enzyme very long-chain acyl-CoA dehydrogenase (VLCAD) in a dose-dependent fashion. In conclusion, inhibition of fatty acid oxidation by nickel, concurrent with increased glucose metabolism, represents a form of metabolic reprogramming that may contribute to nickel-induced carcinogenesis.

Patient-Specific Induced Pluripotent Stem Cell-Derived RPE Cells: Understanding the Pathogenesis of Retinopathy in Long-Chain 3-Hydroxyacyl-CoA Dehydrogenase Deficiency.

PURPOSE: Retinopathy is an important manifestation of trifunctional protein (TFP) deficiencies but not of other defects of fatty acid oxidation. The common homozygous mutation in the TFP α-subunit gene HADHA (hydroxyacyl-CoA dehydrogenase), c.1528G>C, affects the long-chain 3-hydroxyacyl-CoA dehydrogenase (LCHAD) activity of TFP and blindness in infancy. The pathogenesis of the retinopathy is unknown. This study aimed to utilize human induced pluripotent stem cell (hiPSC) technology to create a disease model for the disorder, and to derive clues for retinopathy pathogenesis. METHODS: We implemented hiPSC technology to generate LCHAD deficiency (LCHADD) patient-specific retinal pigment epithelial (RPE) monolayers. These patient and control RPEs were extensively characterized for function and structure, as well as for lipid composition by mass spectrometry. RESULTS: The hiPSC-derived RPE monolayers of patients and controls were functional, as they both were able to phagocytose the photoreceptor outer segments in vitro. Interestingly, the patient RPEs had intense cytoplasmic neutral lipid accumulation, and lipidomic analysis revealed an increased triglyceride accumulation. Further, patient RPEs were small and irregular in shape, and their tight junctions were disorganized. Their ultrastructure showed decreased pigmentation, few melanosomes, and more melanolysosomes. CONCLUSIONS: We demonstrate that the RPE cell model reveals novel early pathogenic changes in LCHADD retinopathy, with robust lipid accumulation, inefficient pigmentation that is evident soon after differentiation, and a defect in forming tight junctions inducing apoptosis. We propose that LCHADD-RPEs are an important model for mitochondrial TFP retinopathy, and that their early pathogenic changes contribute to infantile blindness of LCHADD.

Caring for the woman with acute fatty liver of pregnancy.

Acute fatty liver of pregnancy, although rare, is usually a third trimester of pregnancy occurrence that may be life threatening for both the pregnant woman and the fetus. Often, the onset resembles gastroenteritis or cholecystitis and correct diagnosis is delayed. Because it can also present with preeclampsia and eclampsia, it may be mistakenly diagnosed as hemolysis, elevated liver enzymes, low platelet syndrome. This article presents diagnostic differences between liver conditions that can complicate pregnancy and management strategies for treating and maintaining the well-being of pregnant women, fetuses, and infants who are affected by acute fatty liver of pregnancy. Early recognition and rapid intervention from antepartum diagnosis through delivery and the postpartum period are required by the nursing team and medical providers to reduce maternal and neonatal morbidity and mortality.