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1.
Mol Psychiatry ; 28(4): 1813-1826, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36127429

RESUMO

Mitochondrial DNA variants have previously associated with disease, but the underlying mechanisms have been largely elusive. Here, we report that mitochondrial SNP rs2853499 associated with Alzheimer's disease (AD), neuroimaging, and transcriptomics. We mapped rs2853499 to a novel mitochondrial small open reading frame called SHMOOSE with microprotein encoding potential. Indeed, we detected two unique SHMOOSE-derived peptide fragments in mitochondria by using mass spectrometry-the first unique mass spectrometry-based detection of a mitochondrial-encoded microprotein to date. Furthermore, cerebrospinal fluid (CSF) SHMOOSE levels in humans correlated with age, CSF tau, and brain white matter volume. We followed up on these genetic and biochemical findings by carrying out a series of functional experiments. SHMOOSE acted on the brain following intracerebroventricular administration, differentiated mitochondrial gene expression in multiple models, localized to mitochondria, bound the inner mitochondrial membrane protein mitofilin, and boosted mitochondrial oxygen consumption. Altogether, SHMOOSE has vast implications for the fields of neurobiology, Alzheimer's disease, and microproteins.


Assuntos
Doença de Alzheimer , Humanos , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Proteínas tau/genética , Proteínas tau/metabolismo , Peptídeos beta-Amiloides/metabolismo , Fragmentos de Peptídeos/metabolismo , DNA Mitocondrial/genética , Biomarcadores/líquido cefalorraquidiano , Micropeptídeos
2.
J Nat Prod ; 87(2): 186-194, 2024 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-38277493

RESUMO

The rise of multidrug resistant fungal infections highlights the need to identify and develop novel antifungal agents. Occidiofungin is a nonribosomally synthesized glycolipopeptide that has a unique mechanism of action, disrupting actin-mediated functions and inducing cellular apoptosis. Antifungal activity has been observed in vitro against various fungal species, including multidrug resistant Candida auris, and in vivo efficacy has been demonstrated in a murine vulvovaginal candidiasis model. Occidiofungin, a cyclic glycolipopeptide, is composed of eight amino acids and in previous studies, an asparagine residue was assigned at position 7 (ASN7). In this study, new structural variants of occidiofungin have been characterized which have aspartic acid (ASP7), glutamine (GLN7), or glutamic acid (GLU7) at position 7. The side chain of the ASP7 variant contains the only terminal carboxylic acid in the peptide and provides a useful site for selective chemical modifications. Analogues were synthesized at the ASP7 position and tested for antifungal activity. These analogues were shown to be more active as compared to the ASP7 variant against a panel of Candida species. The naturally occurring variants of occidiofungin with a side chain containing a carboxylic acid at the seventh amino acid position can be used to develop semisynthetic analogues with enhanced therapeutic properties.


Assuntos
Antifúngicos , Burkholderia , Glicopeptídeos , Peptídeos Cíclicos , Camundongos , Animais , Antifúngicos/química , Burkholderia/química , Ácidos Carboxílicos , Testes de Sensibilidade Microbiana
3.
Hepatology ; 73(5): 1747-1763, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-32740973

RESUMO

BACKGROUND AND AIMS: Cholangiocarcinoma (CCA) is a highly lethal disease without effective therapeutic approaches. The whole-genome sequencing data indicate that about 20% of patients with CCA have isocitrate dehydrogenase 1 (IDH1) mutations, which have been suggested to target 2-oxoglutarate (OG)-dependent dioxygenases in promoting CCA carcinogenesis. However, the clinical study indicates that patients with CCA and mutant IDH1 have better prognosis than those with wild-type IDH1, further complicating the roles of 2-OG-dependent enzymes. APPROACH AND RESULTS: This study aimed to clarify if ten-eleven translocation 1 (TET1), which is one of the 2-OG-dependent enzymes functioning in regulating 5-hydroxymethylcytosine (5hmC) formation, is involved in CCA progression. By analyzing The Cancer Genome Atlas (TCGA) data set, TET1 mRNA was found to be substantially up-regulated in patients with CCA when compared with noncancerous bile ducts. Additionally, TET1 protein expression was significantly elevated in human CCA tumors. CCA cells were challenged with α-ketoglutarate (α-KG) and dimethyl-α-KG (DM-α-KG), which are cosubstrates for TET1 dioxygenase. The treatments with α-KG and DM-α-KG promoted 5hmC formation and malignancy of CCA cells. Molecular and pharmacological approaches were used to inhibit TET1 activity, and these treatments substantially suppressed 5hmC and CCA carcinogenesis. Mechanistically, it was found that knockdown of TET1 may suppress CCA progression by targeting cell growth and apoptosis through epigenetic regulation. Consistently, targeting TET1 significantly inhibited CCA malignant progression in a liver orthotopic xenograft model by targeting cell growth and apoptosis. CONCLUSIONS: Our data suggest that expression of TET1 is highly associated with CCA carcinogenesis. It will be important to evaluate TET1 expression in CCA tumors before application of the IDH1 mutation inhibitor because the inhibitor suppresses 2-hydroxyglutarate expression, which may result in activation of TET, potentially leading to CCA malignancy.


Assuntos
Neoplasias dos Ductos Biliares/patologia , Colangiocarcinoma/patologia , Isocitrato Desidrogenase/genética , Oxigenases de Função Mista/genética , Proteínas Proto-Oncogênicas/genética , Translocação Genética/genética , Idoso , Neoplasias dos Ductos Biliares/diagnóstico , Neoplasias dos Ductos Biliares/genética , Western Blotting , Colangiocarcinoma/diagnóstico , Colangiocarcinoma/genética , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Reação em Cadeia da Polimerase em Tempo Real , Regulação para Cima
4.
Catheter Cardiovasc Interv ; 99(1): 181-192, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34402588

RESUMO

OBJECTIVES: The objective was to compare outcomes of redo-aortic valve replacement (AVR) via surgical or transcatheter approach in prior surgical AVR with large percentage of prior stentless surgical AVR. BACKGROUND: With the introduction of transcatheter aortic valve replacement (TAVR), patients with increased surgical risks now have an alternative to redo surgical AVR (SAVR), known as valve-in-valve (ViV) TAVR. Stentless prosthetic aortic valves present a more challenging implantation for ViV-TAVR given the lack of structural frame. METHODS: We performed a retrospective study of 173 subjects who have undergone SAVR (N = 100) or ViV-TAVR (N = 73) in patients with prior surgical AVR at Wake Forest Baptist Medical Center from 2009 to 2019. Our study received the proper ethical oversight. RESULTS: The average ages in redo-SAVR and ViV-TAVR groups were 58.03 ± 13.86 and 66.57 ± 13.44 years, respectively (p < 0.0001). The redo-SAVR had significantly lower STS (2.78 ± 2.09 and 4.68 ± 5.51, p < 0.01) and Euroscores (4.32 ± 2.98 and 7.51 ± 8.24, p < 0.05). The redo-SAVR group had higher percentage requiring mechanical support (8% vs. 0%, p < 0.05) and vasopressors (53% vs. 0%, p < 0.0001), longer length of stay (13.65 ± 11.23 vs. 5.68 ± 7.64 days, p < 0.0001), and inpatient mortality (16% vs. 2.78%, p < 0.005). At 30-day follow-up, redo-SAVR group had higher rates of acute kidney injury (10% vs. 0%, p < 0.01), however ViV-TAVR group had more new left bundle branch blocks (6.85% vs. 0%, p < 0.05). No significant differences regarding re-hospitalization rates, stroke, or death up to 1-year. CONCLUSION: Although the ViV-TAVR group had higher risk patients, there were significantly fewer procedural complications, shorter length of stay, and similar mortality outcomes up to 1-year follow-up.


Assuntos
Estenose da Valva Aórtica , Bioprótese , Implante de Prótese de Valva Cardíaca , Próteses Valvulares Cardíacas , Substituição da Valva Aórtica Transcateter , Adulto , Idoso , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/cirurgia , Estenose da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/cirurgia , Implante de Prótese de Valva Cardíaca/efeitos adversos , Humanos , Pessoa de Meia-Idade , Reoperação , Estudos Retrospectivos , Fatores de Risco , Substituição da Valva Aórtica Transcateter/efeitos adversos , Resultado do Tratamento
5.
J Am Chem Soc ; 143(5): 2304-2314, 2021 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-33501825

RESUMO

The development of fluorescent dyes that emit and absorb light at wavelengths greater than 700 nm and that respond to biochemical and biophysical events in living systems remains an outstanding challenge for noninvasive optical imaging. Here, we report the design, synthesis, and application of near-infrared (NIR)-absorbing and -emitting optical voltmeter based on a sulfonated, phosphine-oxide (po) rhodamine for voltage imaging in intact retinas. We find that po-rhodamine based voltage reporters, or poRhoVRs, display NIR excitation and emission profiles at greater than 700 nm, show a range of voltage sensitivities (13 to 43% ΔF/F per 100 mV in HEK cells), and can be combined with existing optical sensors, like Ca2+-sensitive fluorescent proteins (GCaMP), and actuators, like light-activated opsins ChannelRhodopsin-2 (ChR2). Simultaneous voltage and Ca2+ imaging reveals differences in activity dynamics in rat hippocampal neurons, and pairing poRhoVR with blue-light based ChR2 affords all-optical electrophysiology. In ex vivo retinas isolated from a mouse model of retinal degeneration, poRhoVR, together with GCaMP-based Ca2+ imaging and traditional multielectrode array (MEA) recording, can provide a comprehensive physiological activity profile of neuronal activity, revealing differences in voltage and Ca2+ dynamics within hyperactive networks of the mouse retina. Taken together, these experiments establish that poRhoVR will open new horizons in optical interrogation of cellular and neuronal physiology in intact systems.


Assuntos
Raios Infravermelhos , Imagem Óptica , Óxidos/química , Fosfinas/química , Rodaminas/química , Animais , Cálcio/metabolismo , Corantes Fluorescentes/química , Corantes Fluorescentes/metabolismo , Camundongos , Neurônios/citologia , Neurônios/metabolismo , Retina/citologia , Retina/diagnóstico por imagem , Retina/metabolismo
6.
Dig Dis Sci ; 66(4): 1080-1089, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-32445050

RESUMO

BACKGROUND: Cholangiocarcinoma is a devastating disease with a 2% 5-year survival if the disease has spread outside the liver. The enzyme aspartate beta-hydroxylase (ASPH) has been demonstrated to be highly expressed in cholangiocarcinoma but not in normal bile ducts and found to stimulate tumor cell migration. In addition, it was found that targeting ASPH inhibits cholangiocarcinoma malignant progression. However, it is not clear whether targeting ASPH with the small molecule inhibitor MO-I-1182 suppresses cholangiocarcinoma metastasis. The current study aims to study the efficacy of MO-I-1182 in suppressing cholangiocarcinoma metastasis. METHODS: The analysis was performed in vitro and in vivo with a preclinical animal model by using molecular and biochemical strategies to regulate ASPH expression and function. RESULTS: Knockdown of ASPH substantially inhibited cell migration and invasion in two human cholangiocarcinoma cell lines. Targeting ASPH with a small molecule inhibitor suppressed cholangiocarcinoma progression. Molecular mechanism studies demonstrated that knockdown of ASPH subsequently suppressed protein levels of the matrix metalloproteinases. The ASPH knockdown experiments suggest that this enzyme may modulate cholangiocarcinoma metastasis by regulating matrix metalloproteinases expression. Furthermore, using an ASPH inhibitor in a rat cholangiocarcinoma intrahepatic model established with BED-Neu-CL#24 cholangiocarcinoma cells, it was found that targeting ASPH inhibited intrahepatic cholangiocarcinoma metastasis and downstream expression of the matrix metalloproteinases. CONCLUSION: ASPH may modulate cholangiocarcinoma metastasis via matrix metalloproteinases expression. Taken together, targeting ASPH function may inhibit intrahepatic cholangiocarcinoma metastasis and improve survival.


Assuntos
Proteínas de Ligação ao Cálcio , Colangiocarcinoma , Inibidores Enzimáticos/farmacologia , Neoplasias Hepáticas , Proteínas de Membrana , Oxigenases de Função Mista , Proteínas Musculares , Metástase Neoplásica/prevenção & controle , Animais , Ductos Biliares Intra-Hepáticos/metabolismo , Ductos Biliares Intra-Hepáticos/patologia , Proteínas de Ligação ao Cálcio/antagonistas & inibidores , Proteínas de Ligação ao Cálcio/metabolismo , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Colangiocarcinoma/tratamento farmacológico , Colangiocarcinoma/metabolismo , Colangiocarcinoma/patologia , Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Metaloproteinases da Matriz/metabolismo , Proteínas de Membrana/antagonistas & inibidores , Proteínas de Membrana/metabolismo , Oxigenases de Função Mista/antagonistas & inibidores , Oxigenases de Função Mista/metabolismo , Proteínas Musculares/antagonistas & inibidores , Proteínas Musculares/metabolismo , Ratos
8.
FASEB J ; 33(2): 1824-1835, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30188753

RESUMO

The 5-hydroxymethylcytosine (5hmc) is a newly identified epigenetic modification thought to be regulated by the TET family of proteins. Little information is available about how ethanol consumption may modulate 5hmC formation and alcoholic liver disease (ALD) progression. A rat ALD model was used to study 5hmC in relationship to hepatocyte apoptosis. Human ALD liver samples were also used to validate these findings. It was found that chronic ethanol feeding significantly reduced 5hmC formation in a rat ALD model. There were no significant changes in TET2 and TET3 between the control- and ethanol-fed animals. In contrast, methylcytosine dioxygenase TET1 (TET1) expression was substantially reduced in the ethanol-fed rats and was accompanied by increased hepatocyte apoptosis. Similarly, knockdown of TET1 in human hepatocyte-like cells also significantly promoted apoptosis. Down-regulation of TET1 resulted in elevated expression of the DNA damage marker, suggesting a role for 5hmc in hepatocyte DNA damage as well. Mechanistic studies revealed that inhibition of TET1 promoted apoptotic gene expression. Similarly, targeting TET1 activity by removing cosubstrate promoted apoptosis and DNA damage. Furthermore, treatment with 5-azacitidine significantly mimics these effects, suggesting that chronic ethanol consumption promotes hepatocyte apoptosis and DNA damage by diminishing TET1-mediated 5hmC formation and DNA methylation. In summary, the current study provides a novel molecular insight that TET1-mediated 5hmC is involved in hepatocyte apoptosis in ALD progression.-Ji, C., Nagaoka, K., Zou, J., Casulli, S., Lu, S., Cao, K. Y., Zhang, H., Iwagami, Y., Carlson, R. I., Brooks, K., Lawrence, J., Mueller, W., Wands, J. R., Huang, C.-K. Chronic ethanol-mediated hepatocyte apoptosis links to decreased TET1 and 5-hydroxymethylcytosine formation.


Assuntos
5-Metilcitosina/análogos & derivados , Apoptose/efeitos dos fármacos , Etanol/toxicidade , Hepatócitos/efeitos dos fármacos , Oxigenases de Função Mista/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , 5-Metilcitosina/biossíntese , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular , Dano ao DNA , Desferroxamina/farmacologia , Regulação para Baixo , Epigênese Genética , Técnicas de Silenciamento de Genes , Hepatócitos/citologia , Humanos , Hepatopatias Alcoólicas/metabolismo , Oxigenases de Função Mista/genética , Proteínas Nucleares/metabolismo , Ligação Proteica , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo
10.
J Cell Mol Med ; 22(8): 3987-3995, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29873178

RESUMO

MicroRNAs (miRs) have been recently shown to be heavily involved in the development of alcoholic liver disease (ALD) and suggested as a potential therapeutic target in ALD. The miR-34a was consistently reported to be significantly elevated in several ALD rodent models, but it remains unclear how miR-34a modulates the cellular behaviours of hepatocytes in ALD development and progression. This study aims to characterize alcohol-induced miR-34a impact on hepatocytes growth and apoptosis. The miRNA array was performed to assess changes in miRNA after chronic alcohol feeding. Liver and blood samples were used to examine ALD progression. The miR-34a was overexpressed in human hepatocytes to evaluate its impact on cell growth and apoptosis. Real-time quantitative PCR and Western blot were used to determine the growth and apoptosis molecular signalling pathways associated with miR-34a. Alcohol feeding significantly promoted fatty liver progression, serum ALT levels, apoptosis and miR-34a expression in rat liver. Overexpression of miR-34a in human hepatocytes suppressed cell growth signallings, including c-Met, cyclin D1 and cyclin-dependent kinase 6 (CDK6). The miR-34a might also inhibit the expression of sirtuin 1 (Sirt1) and its target, B-cell lymphoma 2. Interestingly, the expression of miR-34a reverses the suppressive effects of ethanol on cell growth. But, miR-34a promotes hepatocyte senescence and apoptosis. Although the miR-34a-mediated down-regulation of cell growth-associated genes may contribute to cell growth retardation, other miR-34a targets, such as Sirt1, may reverse this phenotype. Future studies will be needed to clarify the role of miR-34a in ALD progression.

11.
Anal Chem ; 90(24): 14316-14320, 2018 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-30444965

RESUMO

Preeclampsia (PE) is a hypertensive disorder of pregnancy and one of the leading contributors to both maternal and perinatal morbidity and mortality. Reliable diagnostic parameters unique to the disorder that accurately define and diagnose PE are currently unavailable. Recent studies have revealed that PE is accompanied by the accumulation of amyloidogenic deposits in the placenta and the presence of congophilic amyloid-like protein aggregates in the urine. Here, we evaluate the capability of an amyloid-targeting aryl cyano amide (ARCAM-1) fluorophore to identify PE patients from analysis of urine samples. Our results reveal that this probe can distinguish patients with PE from gestationally healthy patients and patients suffering from non-PE hypertension, highlighting the potential for amyloid-targeting fluorophores to help identify PE patients during pregnancy.


Assuntos
Amidas/urina , Amiloide/metabolismo , Nitrilas/urina , Pré-Eclâmpsia/diagnóstico , Pré-Eclâmpsia/urina , Amidas/metabolismo , Feminino , Humanos , Nitrilas/metabolismo , Gravidez , Espectrometria de Fluorescência
12.
Prenat Diagn ; 38(7): 475-481, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29663461

RESUMO

The specialty of fetal surgery or fetal intervention is one of the most exciting emerging fields of modern medicine. It is made possible by decades of major developments in antenatal imaging, obstetric anaesthesia, fetal medicine, paediatric surgery, and of course by the bold and novel practitioners willing to take new steps to advance the field. Beginning in the 1970s, it has now reached a stage of maturity where there are several established in utero procedures and countless clinical trials and studies to develop more. But what is the legal situation that fetal surgeons find themselves in? What are the rights and legal protections for the fetus and the mother, both of which are arguably the patient? This article will address this question, discussing and summarising the current legal frameworks governing fetal surgery in the jurisdictions of the United Kingdom, European Court of Human Rights, and the United States of America as well as discuss what the future may hold and how researchers and physicians in the specialty can best navigate the legal environment.


Assuntos
Doenças Fetais/cirurgia , Terapias Fetais , Procedimentos Cirúrgicos Obstétricos/legislação & jurisprudência , Feminino , Direitos Humanos , Humanos , Legislação Médica , Gravidez
13.
Chemistry ; 23(28): 6757-6762, 2017 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-28370726

RESUMO

This paper presents a new hybrid lipid that fuses the ideas of molecular tethering of lipid tails used by archaea and the integration of cholesterol groups used by eukaryotes, thereby leveraging two strategies employed by nature to increase lipid packing in membranes. Liposomes comprised of pure hybrid lipids exhibited a 5-30-fold decrease in membrane leakage of small ions and molecules compared to liposomes that used only one strategy (lipid tethering or cholesterol incorporation) to increase membrane integrity. Molecular dynamics simulations reveal that tethering of lipid tails and integration of cholesterol both reduce the disorder in lipid tails and time-dependent variance in area per lipid within a membrane, leading to tighter lipid packing. These hybrid lipid membranes have exceptional stability in serum, yet can support functional ion channels, can serve as a substrate for phospholipase enzymes, and can be used for liposomal delivery of molecules into living cells.


Assuntos
Eucariotos/metabolismo , Lipídeos/química , Lipossomos/química , Soro/química , Archaea/metabolismo , Linhagem Celular , Colesterol/química , Eucariotos/química , Humanos , Íons/química , Lipídeos/síntese química , Lipossomos/metabolismo , Microscopia de Fluorescência , Simulação de Dinâmica Molecular
14.
J Org Chem ; 80(14): 7019-32, 2015 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-26151079

RESUMO

Clopidogrel is a prodrug anticoagulant with active metabolites that irreversibly inhibit the platelet surface GPCR P2Y12 and thus inhibit platelet activation. However, gaining an understanding of patient response has been limited due to imprecise understanding of metabolite activity and stereochemistry, and a lack of acceptable analytes for quantifying in vivo metabolite formation. Methods for the production of all bioactive metabolites of clopidogrel, their stereochemical assignment, and the development of stable analytes via three conceptually orthogonal routes are disclosed.


Assuntos
Microssomos Hepáticos/metabolismo , Piperidinas/síntese química , Inibidores da Agregação Plaquetária/síntese química , Inibidores da Agregação Plaquetária/metabolismo , Pró-Fármacos/síntese química , Ticlopidina/análogos & derivados , Fenômenos Biológicos , Clopidogrel , Humanos , Microssomos Hepáticos/efeitos dos fármacos , Piperidinas/química , Inibidores da Agregação Plaquetária/química , Pró-Fármacos/química , Estereoisomerismo , Ticlopidina/síntese química , Ticlopidina/química , Ticlopidina/metabolismo
15.
Clin Pract Cases Emerg Med ; 8(1): 64-67, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38546316

RESUMO

Introduction: Heterotopic pregnancy, defined as simultaneous intrauterine and ectopic pregnancy, is a rare and potentially life-threatening condition. The incidence of heterotopic pregnancy has significantly increased in the modern era, primarily due to use of assisted reproductive technology. Heterotopic pregnancy in the absence of risk factors is uncommon. The symptoms of heterotopic pregnancy are similar to those of ectopic pregnancy, primarily abdominal pain and vaginal bleeding. Case Report: We report a case of heterotopic pregnancy occurring in the absence of risk factors and presenting with primary symptoms of chest pain and shortness of breath. Conclusion: While uncommon, heterotopic pregnancy may occur in patients without risk factors and may present with atypical symptoms such as chest pain and shortness of breath.

16.
Cancer Lett ; 580: 216493, 2024 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-37977350

RESUMO

Cholangiocarcinoma (CCA) is resistant to systemic chemotherapies that kill malignant cells mainly through DNA damage responses (DDRs). Recent studies suggest that the involvement of 2-oxoglutarate (2-OG) dependent dioxygenases in DDRs may be associated with chemoresistance in malignancy, but how 2-OG impacts DDRs in CCA chemotherapy remains elusive. We examined serum 2-OG levels in CCA patients before receiving chemotherapy. CCA patients are classified as progressive disease (PD), partial response (PR), and stable disease (SD) after receiving chemotherapy. CCA patients classified as PD showed significantly higher serum 2-OG levels than those defined as SD and PR. Treating CCA cells with 2-OG reduced DDRs. Overexpression of full-length aspartate beta-hydroxylase (ASPH) could mimic the effects of 2-OG on DDRs, suggesting the important role of ASPH in chemoresistance. Indeed, the knockdown of ASPH improved chemotherapy in CCA cells. Targeting ASPH with a specific small molecule inhibitor also enhanced the effects of chemotherapy. Mechanistically, ASPH modulates DDRs by affecting ATM and ATR, two of the major regulators finely controlling DDRs. More importantly, targeting ASPH improved the therapeutic potential of chemotherapy in two preclinical CCA models. Our data suggested the impacts of elevated 2-OG and ASPH on chemoresistance through antagonizing DDRs. Targeting ASPH may enhance DDRs, improving chemotherapy in CCA patients.


Assuntos
Neoplasias dos Ductos Biliares , Colangiocarcinoma , Humanos , Ácido Aspártico/metabolismo , Neoplasias dos Ductos Biliares/tratamento farmacológico , Neoplasias dos Ductos Biliares/genética , Ductos Biliares Intra-Hepáticos , Colangiocarcinoma/tratamento farmacológico , Colangiocarcinoma/genética , Dano ao DNA , Ácidos Cetoglutáricos , Oxigenases de Função Mista/genética
17.
Aging Cell ; 23(7): e14153, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38520065

RESUMO

The APOE4 allele is recognized as a significant genetic risk factor to Alzheimer's disease (AD) and influences longevity. Nonetheless, some APOE4 carriers exhibit resistance to AD even in advanced age. Humanin, a mitochondrial-derived peptide comprising 24 amino acids, has variants linked to cognitive resilience and longevity. Our research uncovered a unique humanin variant, P3S, specifically enriched in centenarians with the APOE4 allele. Through in silico analyses and subsequent experimental validation, we demonstrated a strong affinity between humanin P3S and APOE4. Utilizing an APOE4-centric mouse model of amyloidosis (APP/PS1/APOE4), we observed that humanin P3S significantly attenuated brain amyloid-beta accumulation compared to the wild-type humanin. Transcriptomic assessments of mice treated with humanin P3S highlighted its potential mechanism involving the enhancement of amyloid beta phagocytosis. Additionally, in vitro studies corroborated humanin P3S's efficacy in promoting amyloid-beta clearance. Notably, in the temporal cortex of APOE4 carriers, humanin expression is correlated with genes associated with phagocytosis. Our findings suggest a role of the rare humanin variant P3S, especially prevalent among individuals of Ashkenazi descent, in mitigating amyloid beta pathology and facilitating phagocytosis in APOE4-linked amyloidosis, underscoring its significance in longevity and cognitive health among APOE4 carriers.


Assuntos
Apolipoproteína E4 , Encéfalo , Longevidade , Apolipoproteína E4/genética , Apolipoproteína E4/metabolismo , Humanos , Longevidade/genética , Camundongos , Animais , Encéfalo/metabolismo , Encéfalo/patologia , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Camundongos Transgênicos , Peptídeos beta-Amiloides/metabolismo , Masculino , Feminino , Idoso de 80 Anos ou mais , Heterozigoto , Modelos Animais de Doenças , Peptídeos e Proteínas de Sinalização Intracelular
18.
Gels ; 9(10)2023 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-37888361

RESUMO

Fungal infections are caused by opportunistic pathogens that can be life threatening or debilitating. Candida spp. are becoming increasingly resistant to current clinically approved antifungal therapeutics. Candida infections afflict not only immunosuppressed but also immunocompetent individuals. Recurrent vulvovaginal candidiasis (RVVC) is a disease that afflicts 5-9% of women. Occidiofungin is a novel cyclic peptide that has a broad spectrum of antifungal activity with a novel fungicidal mechanism of action. A gel formulation containing occidiofungin (OCF001) is being developed for use to treat vulvovaginal candidiasis. The formulated gel for intravaginal application used hydroxyethyl cellulose as the primary gelling agent and hydroxypropyl ß-cyclodextrin as a solubilizing agent for occidiofungin. Franz cells and LC-MS/MS were used to determine the rate of drug substance diffusion in the gel formulation. The formulation was tested in an ex vivo mouse skin efficacy study, and the safety was tested following repeat intravaginal administration in rabbits. In this study, the gel formulation was shown to reduce the drug substance rate of diffusion across a skin memetic membrane. The study showed that the formulation extends exposure time to inhibitory concentrations of occidiofungin over a 24-h period and supports a single daily application for the treatment of RVVC.

19.
STAR Protoc ; 4(4): 102649, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37874679

RESUMO

Small open reading frame (smORF)-encoded microproteins, proteins containing less than 100-150 amino acids, are an emerging class of functional biomolecules. Here, we present a protocol for identifying translated smORFs in mammalian systems genome wide. We describe steps for generation of ribosome profiling (Ribo-seq) data, in silico translation of a transcriptome assembly to create an ORF database, and computational analysis of Ribo-seq to score individual smORFs for translation. Identification of translated smORFs is the first step to studying the functions of microproteins. For complete details on the use and execution of this protocol, please refer to Martinez et al.1.


Assuntos
Micropeptídeos , Proteínas , Animais , Fases de Leitura Aberta/genética , Fluxo de Trabalho , Proteínas/genética , Genoma , Mamíferos
20.
Elife ; 122023 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-37039777

RESUMO

The retina, behind the transparent optics of the eye, is the only neural tissue whose physiology and pathology can be non-invasively probed by optical microscopy. The aberrations intrinsic to the mouse eye, however, prevent high-resolution investigation of retinal structure and function in vivo. Optimizing the design of a two-photon fluorescence microscope (2PFM) and sample preparation procedure, we found that adaptive optics (AO), by measuring and correcting ocular aberrations, is essential for resolving putative synaptic structures and achieving three-dimensional cellular resolution in the mouse retina in vivo. Applying AO-2PFM to longitudinal retinal imaging in transgenic models of retinal pathology, we characterized microvascular lesions with sub-capillary details in a proliferative vascular retinopathy model, and found Lidocaine to effectively suppress retinal ganglion cell hyperactivity in a retinal degeneration model. Tracking structural and functional changes at high-resolution longitudinally, AO-2PFM enables microscopic investigations of retinal pathology and pharmacology for disease diagnosis and treatment in vivo.


Assuntos
Retina , Degeneração Retiniana , Camundongos , Animais , Retina/patologia , Células Ganglionares da Retina , Degeneração Retiniana/patologia , Microscopia de Fluorescência , Óptica e Fotônica
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