Design, synthesis, and anti-cancer evaluation of C-14 arylcarbamate derivatives of andrographolide.

In this study, we explored a concise and mild synthetic route to produce novel C-14 arylcarbamate derivatives of andrographolide, a known anti-inflammatory and anticancer natural product. Upon assessing their anti-cancer efficacy against pancreatic ductal adenocarcinoma (PDAC) cells, some derivatives showed stronger cytotoxicity against PANC-1 cells than andrographolide. In addition, we demonstrated one derivative, compound 3m, effectively reduced the expression of oncogenic p53 mutant proteins (p53R273H and p53R248W), proliferation, and migration in PDAC lines, PANC-1 and MIA PaCa-2. Accordingly, the novel derivative holds promise as an anti-cancer agent against pancreatic cancer. In summary, our study broadens the derivative library of andrographolide and develops an arylcarbamate derivative of andrographolide with promising anticancer activity against PDAC.

Gender Differences in the Attitudes of Parents Living with Adult Children with Schizophrenia.

BACKGROUND: This paper explored the gender differences in the attitudes of parents toward taking care of their adult daughters or sons with schizophrenia, and focused on how parents define and think about the roles of their children, and how they cope with fulfilling the expected roles. METHODS: Qualitative research design and purpose sampling were used to enroll parents who had adult patients with schizophrenia at a medical center in central Taiwan. Semi-structured in-depth interviews were conducted and content analysis was used to analyze the data. RESULTS: Seven main themes emerged from the data provided by ten parents living with adult children with schizophrenia. Three themes that focused on gender difference are listed: parents continue to expect their sons with schizophrenia to carry on the family name; society as a whole expects males to be the "head of the family"; male family members are supposed to assume the responsibility of caring for siblings with schizophrenia. CONCLUSIONS: The results of the study could help clinical professionals to understand and have greater empathy with regard to the difficulties for families and the concerns of parents taking care of their children with schizophrenia in the specific context of Chinese culture, and to provide more efficient and responsive assistance.

Homocysteine is a bystander for ST-segment elevation myocardial infarction: a case-control study.

BACKGROUND: Homocysteine has been long considered a risk factor for atherosclerosis. However, cardiovascular events cannot be reduced through homocysteine lowering by B vitamin supplements. Although several association studies have reported an elevation of serum homocysteine levels in cardiovascular diseases, the relationship of homocysteine with ST-segment elevation myocardial infarction (STEMI) is not well established. METHODS: We prospectively enrolled STEMI patients who were consecutively admitted to an intensive care unit following coronary intervention in a single medical center in Taiwan. Control subjects were individuals who presented to the outpatient or emergency department with acute chest pain but subsequently revealed patent coronary arteries by coronary arteriography. The association between serum homocysteine levels and STEMI was investigated. A culture system using human coronary artery endothelial cells was also established to examine the toxic effects of homocysteine at the cellular level. RESULTS: Patients with chest pain were divided into two groups. The STEMI group included 56 patients who underwent a primary percutaneous coronary intervention. The control group included 17 subjects with patent coronary arteries. There was no difference in serum homocysteine levels (8.4 ± 2.2 vs. 7.6 ± 1.9 µmol/L, p = 0.142). When stratifying STEMI patients by the Killip classification into higher (Killip III-IV) and lower (Killip I-II) grades, CRP (3.3 ± 4.1 vs. 1.4 ± 2.3 mg/L, p = 0.032), peak creatine kinase (3796 ± 2163 vs. 2305 ± 1822 IU/L, p = 0.023), and SYNTAX scores (20.4 ± 11.1 vs. 14.8 ± 7.6, p = 0.033) were significantly higher in the higher grades, while serum homocysteine levels were similar. Homocysteine was not correlated with WBCs, CRP, or the SYNTAX score in STEMI patients. In a culture system, homocysteine at even a supraphysiological level of 100 µmol/L did not reduce the cell viability of human coronary artery endothelial cells. CONCLUSIONS: Homocysteine was not elevated in STEMI patients regardless of Killip severity, suggesting that homocysteine is a bystander instead of a causative factor of STEMI. Our study therefore supports the current notion that homocysteine-lowering strategies are not essential in preventing cardiovascular disease.

Electronegative L5-LDL induces the production of G-CSF and GM-CSF in human macrophages through LOX-1 involving NF-κB and ERK2 activation.

BACKGROUND AND AIMS: Circulating levels of granulocyte colony-stimulating factor (G-CSF) and granulocyte macrophage colony-stimulating factor (GM-CSF) are associated with the severity of acute myocardial infarction (AMI). However, what causes increases in G-CSF and GM-CSF is unclear. In this study, we investigated whether L5-low-density lipoprotein (LDL), a mildly oxidized LDL from AMI, can induce G-CSF and GM-CSF production in human macrophages. METHODS: L1-LDL and L5-LDL were isolated through anion-exchange chromatography from AMI plasma. Human macrophages derived from THP-1 and peripheral blood mononuclear cells were treated with L1-LDL, L5-LDL, or copper-oxidized LDL (Cu-oxLDL) and G-CSF and GM-CSF protein levels in the medium were determined. In addition, the effects of L5-LDL on G-CSF and GM-CSF production were tested in lectin-type oxidized LDL receptor-1 (LOX-1), CD36, extracellular signal-regulated kinase (ERK) 1, and ERK2 knockdown THP-1 macrophages. RESULTS: L5-LDL but not L1-LDL or Cu-oxLDL significantly induced production of G-CSF and GM-CSF in macrophages. In vitro oxidation of L1-LDL and L5-LDL altered their ability to induce G-CSF and GM-CSF, suggesting that the degree of oxidation is critical for the effects. Knockdown and antibody neutralization experiments suggested that the effects were caused by LOX-1. In addition, nuclear factor (NF)-κB and ERK1/2 inhibition resulted in marked reductions of L5-LDL-induced G-CSF and GM-CSF production. Moreover, knockdown of ERK2, but not ERK1, hindered L5-LDL-induced G-CSF and GM-CSF production. CONCLUSIONS: The results indicate that L5-LDL, a naturally occurring mild oxidized LDL, induced G-CSF and GM-CSF production in human macrophages through LOX-1, ERK2, and NF-κB dependent pathways.

The Effects of an Exercise Program on Anxiety Levels and Metabolic Functions in Patients With Anxiety Disorders.

The purpose of this study was to evaluate the effects of a home-based (HB) exercise program on anxiety levels and metabolic functions in patients with anxiety disorders in Taiwan. Purposive sampling was used to recruit 86 participants for this randomized, experimental study. Participants were asked to complete a pretest before the 3-month exercise program, a posttest at 1 week, and a follow-up test at 3 months after the exercise program. Study measures included four Self-Report Scales and biophysical assessments to collect and assess personal data, lifestyle behaviors, anxiety levels, and metabolic control functions. Of the 86 study participants, 83 completed the posttest and the 3-month follow-up test, including 41 in the experimental group and 42 in the control group. Participants in the experimental group showed significant improvements in body mass index, high-density lipoprotein cholesterol levels, and the level of moderate exercise after the program relative to the control group, as analyzed by generalized estimating equations mixed-model repeated measures. State and trait anxiety levels were also significantly improved from pretest to follow-up test in the experimental group. Finally, the prevalence of metabolic syndrome declined for participants in the experimental group. The HB exercise program produced positive effects on the metabolic indicators and anxiety levels of Taiwanese adults with anxiety disorders. Health providers should consider using similar HB exercise programs to help improve the mental and physical health of patients with anxiety disorders in their communities.

L5-LDL from ST-elevation myocardial infarction patients induces IL-1ß production via LOX-1 and NLRP3 inflammasome activation in macrophages.

L5-LDL, the most electronegative LDL associated with major cardiovascular risks, significantly rises in patients with ST-segment elevation myocardial infarction (STEMI). The inflammatory nature of atherosclerotic vascular diseases has prompted us to investigate whether L5-LDL induces the production of inflammatory cytokines, especially vascular ischemia-related interleukin (IL)-1ß, in the pathogenesis of STEMI. Clinical data showed that plasma levels of L5-LDL and IL-1ß were higher in the STEMI patients than in the controls (P < 0.05). In THP-1-derived human macrophages, L5-LDL significantly increased the levels of both IL-1ß and cleaved caspase-1, indicating the activation of NOD-like receptor pyrin domain containing 3 (NLRP3) inflammasomes by L5-LDL. Knockdown of NLRP3 and its adaptor protein apoptosis-associated speck-like protein containing a CARD (ASC) resulted in decreased L5-LDL-induced IL-1ß. Furthermore, knock down of the lectin-type oxidized LDL receptor (LOX-1) in THP-1 cells attenuated L5-LDL-induced activation of NF-κB and caspase-1, leading to subsequent inhibition of IL-1ß in macrophages. Furthermore, blockade LOX-1 with neutralizing antibody also inhibited L5-LDL-induced IL-1ß in human peripheral blood mononuclear cell-derived macrophages. In conclusion, L5-LDL induces IL-1ß production in macrophages by activation of NF-κB and caspase-1 through the LOX-1-dependent pathway. This study represents the evidence linking L5-LDL and the inflammatory cytokine IL-1ß in STEMI, and identifies L5-LDL as a novel therapeutic target in acute myocardial infarction. NEW & NOTEWORTHY: This study represents the evidence linking L5-LDL and the inflammatory cytokine IL-1ß in ST-segment elevation myocardial infarction (STEMI). We elucidate the molecular mechanism underlying L5-LDL-induced production of IL-1ß in macrophages. The results showed that L5-LDL induced activation of caspase-1 and NF-κB through the lectin-type oxidized LDL receptor (LOX-1)-dependent pathway, leading to the production of IL-1ß.

Electronegative LDL is linked to high-fat, high-cholesterol diet-induced nonalcoholic steatohepatitis in hamsters.

The pathogenesis of nonalcoholic steatohepatitis (NASH), like that of atherosclerosis, involves lipid accumulation, inflammation and fibrosis. Recent studies suggest that oxidized LDL (oxLDL) may be a risk factor for NASH, but oxLDL levels were not directly measured in these studies. The aim of this study was to examine whether there was an association between electronegative LDL [LDL(-)], a mildly oxLDL found in the blood, and the development of NASH using two animal models. Golden Syrian hamsters and C57BL/6 mice were fed a high-fat, high-cholesterol (HFC) diet for 6 or 12weeks, then liver lipid and histopathology, plasma lipoprotein profile and LDL(-) levels were examined. The HFC-diet-fed hamsters and mice had similar levels of hepatic lipid but different histopathological changes, with microvesicular steatosis, hepatocellular hypertrophy, inflammation and bridging fibrosis in the hamsters, but only in mild steatohepatitis with low inflammatory cell infiltration in the mice. It also resulted in a significant increase in plasma levels of LDL cholesterol and LDL(-) in hamsters, but only a slight increase in mice. Moreover, enlarged Kupffer cells, LDL(-) and accumulation of unesterified cholesterol were detected in the portal area of HFC-diet-fed hamsters, but not HFC-diet-fed mice. An in vitro study showed that LDL(-) from HFC-diet-fed hamsters induced TNF-α secretion in rat Kupffer cell through a LOX-1-dependent pathway. Our results strongly suggest that LDL(-) is one of the underlying causes of hepatic inflammation and plays a critical role in the development of NASH.

[The Discursive Analysis of Mental Health Promotion Efforts Targeting Community-Dwelling Young Adults at High Risk of Mental Illness].

The mental health of adolescents and young adults is an issue of concern worldwide due to the increase in violent incidents that have been perpetrated by members of this age group. Young people at high-risk of mental disability are easily ignored. Therefore, social tensions in society have increased due to safety issues arising from the problems that are associated with mental disabilities in this population. This paper discusses the importance of early identification and early prevention of mental disabilities in high-risk young people, defines high-risk mental illness, and identifies the various subcategories of mental diseases. Based on our review of the literature, the present paper suggests targeting young people in high-risk categories with health promotion that addresses the following six health-promotion lifestyle habits: engaging in regular exercise, eating a balanced diet, managing stress, engaging in social relationships, taking responsibility for personal health, and fulfilling self-actualization. This discursive analysis discusses these strategies as safe and sustained interventions for adolescents and young adults that may improve self-awareness and thus maintain health and enhance opportunities to promote an ideal health status.

IL-1ß promotes malignant transformation and tumor aggressiveness in oral cancer.

Chronic inflammation, coupled with alcohol, betel quid, and cigarette consumption, is associated with oral squamous cell carcinoma (OSCC). Interleukin-1 beta (IL-1ß) is a critical mediator of chronic inflammation and implicated in many cancers. In this study, we showed that increased pro-IL-1ß expression was associated with the severity of oral malignant transformation in a mouse OSCC model induced by 4-Nitroquinolin-1-oxide (4-NQO) and arecoline, two carcinogens related to tobacco and betel quid, respectively. Using microarray and quantitative PCR assay, we showed that pro-IL-1ß was upregulated in human OSCC tumors associated with tobacco and betel quid consumption. In a human OSCC cell line TW2.6, we demonstrated nicotine-derived nitrosamine ketone (NNK) and arecoline stimulated IL-1ß secretion in an inflammasome-dependent manner. IL-1ß treatment significantly increased the proliferation and dysregulated the Akt signaling pathways of dysplastic oral keratinocytes (DOKs). Using cytokine antibodies and inflammation cytometric bead arrays, we found that DOK and OSCC cells secreted high levels of IL-6, IL-8, and growth-regulated oncogene-α following IL-1ß stimulation. The conditioned medium of IL-1ß-treated OSCC cells exerted significant proangiogenic effects. Crucially, IL-1ß increased the invasiveness of OSCC cells through the epithelial-mesenchymal transition (EMT), characterized by downregulation of E-cadherin, upregulation of Snail, Slug, and Vimentin, and alterations in morphology. These findings provide novel insights into the mechanism underlying OSCC tumorigenesis. Our study suggested that IL-1ß can be induced by tobacco and betel quid-related carcinogens, and participates in the early and late stages of oral carcinogenesis by increasing the proliferation of dysplasia oral cells, stimulating oncogenic cytokines, and promoting aggressiveness of OSCC.

Malondialdehyde mediates oxidized LDL-induced coronary toxicity through the Akt-FGF2 pathway via DNA methylation.

BACKGROUND: Oxidized LDL (oxLDL) is involved in the development of atherosclerotic heart disease through a mechanism that is not fully understood. In this study, we examined the role of malondialdehyde (MDA), an important oxidative stress epitope of oxLDL, in mediating coronary endothelial cytotoxicity. RESULTS: Human coronary artery endothelial cells (HCAECs) were treated with oxLDL in the presence or absence of antibody against MDA (anti-MDA) or apoB100 (anti-apoB100). In HCAECs treated with oxLDL (100 µg/ml) alone, DNA synthesis, cell viability, and expression of prosurvival fibroblast growth factor 2 (FGF2) were significantly reduced (P < 0.01 vs phosphate buffered saline-treated cells). These inhibitory effects of oxLDL were significantly attenuated in HCAECs cotreated with anti-MDA (0.15 µg/ml; P < 0.05 vs oxLDL-treated cells), but not in those cotreated with anti-apoB100. When we tested the effects of a panel of signal transduction modifiers on the signal transduction pathways of MDA in oxLDL-treated HCAECs, we found that MDA-induced cytotoxicity was mediated partly through the Akt pathway. Using a reporter gene assay, we identified an oxLDL-response element in the FGF2 promoter that was responsible for the transcriptional repression of FGF2 by oxLDL. The results of bisulfite genomic DNA sequencing showed that in HCAECs treated with oxLDL, the GC-rich promoter of FGF2 was heavily methylated at cytosine residues, whereas cotreatment with anti-MDA markedly reduced oxLDL-induced FGF2 promoter methylation. CONCLUSION: OxLDL disrupts the growth and survival of HCAECs through an MDA-dependent pathway involving methylation of the FGF2 promoter and repression of FGF2 transcription. This novel epigenetic mechanism of oxLDL may underlie its atherogenicity in patients with atherosclerotic cardiovascular disease.

[Assay of screening and prevention issues for high risk populations with prodromes of severe mental illness].

Before the appearance of specific psychotic symptoms, most individuals experience a period of prodromal symptoms associated with severe mental illness. Early intervention during this pre-psychotic phase may improve treatment outcomes, alter the natural course of disease, and prevent or delay mental disease onset. This paper aimed to synthesize four screening strategies (genetic high-risk populations selected by family history with mental illness, finding ultra-high-risk population, the close-in strategy, and the pre-psychotic phase by assessing basic symptoms); two intervention dimensions (psychosocial interventions and antipsychotic medicine); discussions of ethnic issues; and three Taiwanese nurses' roles (the role of assessment for screening, the role of development for screening tools, and the role of preventive intervention providers) to attain early diagnoses and prevention of mental illness. This article provides more information to advanced Taiwanese mental health nurses responsible to promote /s enhance the health of patients with prodromes of severe mental illness.

Aspirin protects human coronary artery endothelial cells against atherogenic electronegative LDL via an epigenetic mechanism: a novel cytoprotective role of aspirin in acute myocardial infarction.

AIMS: L5 is the most negatively charged subfraction of human low-density lipoprotein (LDL) and is the only subfraction of LDL capable of inducing apoptosis in cultured vascular endothelial cells (ECs) by inhibiting fibroblast growth factor-2 (FGF2) transcription. We examined whether plasma L5 levels are elevated in patients with ST-segment elevation myocardial infarction (STEMI) and whether aspirin provides epigenetic protection of human coronary artery ECs (HCAECs) exposed to L5. METHODS AND RESULTS: Plasma L5 levels were compared between patients with STEMI (n = 10) and control subjects with chest pain syndrome but a normal coronary arteriogram (n = 5). L5 was isolated from the plasma of STEMI patients and control subjects, and apoptosis, FGF2 expression, and FGF2 promoter methylation were examined in HCAECs treated with L5 and aspirin. Plasma L5 levels were significantly higher in STEMI patients than in control subjects (P < 0.001). Treatment of HCAECs with L5 resulted in reduced survival and FGF2 expression and increased CpG methylation of the FGF2 promoter. Co-treatment of HCAECs with L5 and a physiologically relevant, low concentration of aspirin (0.2 mM) attenuated the adverse effects of L5 on HCAEC survival, FGF2 expression, and FGF2 promoter methylation. In contrast, high concentrations of aspirin (≥1.0 mM) accentuated the effects of L5. CONCLUSIONS: Our results show that L5 levels are significantly increased in STEMI patients. Furthermore, L5 impairs HCAEC function through CpG methylation of the FGF2 promoter, which is suppressed in the presence of low-concentration aspirin. Our results provide evidence of a novel mechanism of aspirin in the prevention of MI.

Profiling lipid-protein interactions using nonquenched fluorescent liposomal nanovesicles and proteome microarrays.

Fluorescent liposomal nanovesicles (liposomes) are commonly used for lipid research and/or signal enhancement. However, the problem of self-quenching with conventional fluorescent liposomes limits their applications because these liposomes must be lysed to detect the fluorescent signals. Here, we developed a nonquenched fluorescent (NQF)1 liposome by optimizing the proportion of sulforhodamine B (SRB) encapsulant and lissamine rhodamine B-dipalmitoyl phosphatidylethanol (LRB-DPPE) on a liposomal surface for signal amplification. Our study showed that 0.3% of LRB-DPPE with 200 µm of SRB provided the maximal fluorescent signal without the need to lyse the liposomes. We also observed that the NQF liposomes largely eliminated self-quenching effects and produced greatly enhanced signals than SRB-only liposomes by 5.3-fold. To show their application in proteomics research, we constructed NQF liposomes that contained phosphatidylinositol 3,5-bisphosphate (PI(3,5)P2) and profiled its protein interactome using a yeast proteome microarray. Our profiling led to the identification of 162 PI(3,5)P2-specific binding proteins (PI(3,5)P2-BPs). We not only recovered many proteins that possessed known PI(3,5)P2-binding domains, but we also found two unknown Pfam domains (Pfam-B_8509 and Pfam-B_10446) that were enriched in our dataset. The validation of many newly discovered PI(3,5)P2-BPs was performed using a bead-based affinity assay. Further bioinformatics analyses revealed that the functional roles of 22 PI(3,5)P2-BPs were similar to those associated with PI(3,5)P2, including vesicle-mediated transport, GTPase, cytoskeleton, and kinase. Among the 162 PI(3,5)P2-BPs, we found a novel motif, HRDIKP[ES]NJLL that showed statistical significance. A docking simulation showed that PI(3,5)P2 interacted primarily with lysine or arginine side chains of the newly identified PI(3,5)P2-binding kinases. Our study showed that this new tool would greatly benefit profiling lipid-protein interactions in high-throughput studies.

Intervening conditions of hospital-based home care for people with severe mental illness.

OBJECTIVE: This study discusses the intervening conditions of hospital-based home care (HBHC) for people with severe mental illness in Taiwan. DESIGN AND SAMPLE: Grounded theory of the Strauss and Corbin approach was used. Participants were selected from six hospitals in Central Taiwan, including 21 clients, 19 caregivers, and 25 professionals. MEASURES: Semi-structured one-on-one interviews were used to collect data. Data analysis consisted of three stages: open, axial, and selective coding. Data analysis, data collection, and sampling were conducted through the constant comparative analysis process. RESULTS: Two categories were generated as positive and negative intervening conditions of HBHC services. Eight positive effects and nine negative effects were generated from the data. CONCLUSIONS: Several positive and negative intervening conditions were found in this study to affect the delivery of HBHC. Government support and several limitations regarding HBHC services quality should be noticed and improved.

Zebrafish arl6ip1 is required for neural crest development during embryogenesis.

BACKGROUND: Although the embryonic expression pattern of ADP ribosylation factor-like 6 interacting protein 1 (Arl6ip1) has been reported, its function in neural crest development is unclear. METHODS/PRINCIPAL FINDINGS: We found that knockdown of Arl6ip1 caused defective embryonic neural crest derivatives that were particularly severe in craniofacial cartilages. Expressions of the ectodermal patterning factors msxb, dlx3b, and pax3 were normal, but the expressions of the neural crest specifier genes foxd3, snai1b, and sox10 were greatly reduced. These findings suggest that arl6ip1 is essential for specification of neural crest derivatives, but not neural crest induction. Furthermore, we revealed that the streams of crestin- and sox10-expressing neural crest cells, which migrate ventrally from neural tube into trunk, were disrupted in arl6ip1 morphants. This migration defect was not only in the trunk neural crest, but also in the enteric tract where the vagal-derived neural crest cells failed to populate the enteric nervous system. We found that this migration defect was induced by dampened Shh signaling, which may have resulted from defective cilia. These data further suggested that arl6ip1 is required for neural crest migration. Finally, by double-staining of TUNEL and crestin, we confirmed that the loss of neural crest cells could not be attributed to apoptosis. CONCLUSIONS/SIGNIFICANCE: Therefore, we concluded that arl6ip1 is required for neural crest migration and sublineage specification.

Nkx2.7 and Nkx2.5 function redundantly and are required for cardiac morphogenesis of zebrafish embryos.

BACKGROUND: Nkx2.7 is the tinman-related gene, as well as orthologs of Nkx2.5 and Nkx-2.3. Nkx2.7 and Nkx2.5 express in zebrafish heart fields of lateral plate mesoderm. The temporal and spatial expression patterns of Nkx2.7 are similar to those of Nkx2.5, but their functions during cardiogenesis remain unclear. METHODOLOGY/PRINCIPAL FINDINGS: Here, Nkx2.7 is demonstrated to compensate for Nkx2.5 loss of function and play a predominant role in the lateral development of the heart, including normal cardiac looping and chamber formation. Knocking down Nkx2.5 showed that heart development was normal from 24 to 72 hpf. However, when knocking down either Nkx2.7 or Nkx2.5 together with Nkx2.7, it appeared that the heart failed to undergo looping and showed defective chambers, although embryos developed normally before the early heart tube stage. Decreased ventricular myocardium proliferation and defective myocardial differentiation appeared to result from late-stage up-regulation of bmp4, versican, tbx5 and tbx20, which were all expressed normally in hearts at an early stage. We also found that tbx5 and tbx20 were modulated by Nkx2.7 through the heart maturation stage because an inducible overexpression of Nkx2.7 in the heart caused down-regulation of tbx5 and tbx20. Although heart defects were induced by overexpression of an injection of 150-pg Nkx2.5 or 5-pg Nkx2.7 mRNA, either Nkx2.5 or Nkx2.7 mRNA rescued the defects induced by Nkx2.7-morpholino(MO) and Nkx2.5-MO with Nkx2.7-MO. CONCLUSIONS AND SIGNIFICANCE: Therefore, we conclude that redundant activities of Nkx2.5 and Nkx2.7 are required for cardiac morphogenesis, but that Nkx2.7 plays a more critical function, specifically indicated by the gain-of-function and loss-of- function experiments where Nkx2.7 is observed to regulate the expressions of tbx5 and tbx20 through the maturation stage.

The embryonic expression patterns and the knockdown phenotypes of zebrafish ADP-ribosylation factor-like 6 interacting protein gene.

ADP-ribosylation factor-like 6 (Arl6) mutation is linked to human disease and Arl6 interacts with Arl6 interacting protein (Arl6ip). However, the expression pattern and function of Arl6ip during embryogenesis are unknown. To confirm whether abnormal Arl6ip function might result in embryonic defects in zebrafish, we examined the expression patterns of arl6ip during embryogenesis, and they were maternally expressed and exhibited in the brain, optic primordia, hypochord, spinal cord, myotome, heart, fin-bud, kidney, trunk, and retina. Knockdown of Arl6ip revealed the following phenotypic defects: microphthalmia, disorganized pigment pattern, flat head, defective tectum, deficient pectoral fins, abnormal pneumatic duct, pericardial edema, and deformed trunk. Particularly, histological dissection of the retinae of arl6ip-morphants revealed that neuronal differentiation is severely delayed, resulting in no formation of retinal layers. We further confirmed that opsins of arl6ip-morphants were not transcribed. Based on this evidence, Arl6ip may play important roles in zebrafish ocular, heart, and fin-bud development.