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1.
Protein Expr Purif ; 215: 106419, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38110109

RESUMEN

A lipase EstA from Bacillus subtilis KM-BS was expressed in Escherichia coli BL21 (DE3) cells. The recombinant enzyme achieved high activity (49.67 U/mL) with protein concentration of 1.29 mg/mL under optimal conditions at the large-scale expression of 6 h and post-induction time at 30 °C using 0.1 mM isopropyl-ß-d-thiogalactopyranoside (IPTG). The optimal temperature and pH of the purified enzyme were at 45-55 °C and pH 8.0 - 9.0, respectively. Activity of the purified enzyme was stable in the presence of 1 mM Ca2+; stimulated by 1 mM Mg2+ and Mn2+, and inhibited by Fe3+. A significant amount of fatty acids was released during the hydrolysis of waste cooking oil under the catalysis of purified lipase, indicating that this recombinant lipase showed promise as a suitable candidate in industrial fields, particularly in biodiesel and detergent sector.


Asunto(s)
Bacillus subtilis , Lipasa , Hidrólisis , Bacillus subtilis/metabolismo , Catálisis , Culinaria , Temperatura
2.
Nutr Metab Cardiovasc Dis ; 34(3): 633-641, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38161124

RESUMEN

BACKGROUND AND AIMS: To prospectively investigate associations of plasma sphingolipids with insulin sensitivity, ß-cell function, and incident diabetes in the Japanese American Community Diabetes Study. METHODS AND RESULTS: Baseline plasma samples from adults without diabetes (n = 349; mean age 56.7 years, 51 % men) were assayed for circulating ceramide and sphingomyelin species. Adjusted regression models examined cross-sectional and longitudinal associations with insulin sensitivity (HOMA2-%S), ß-cell function (oral disposition index: DIo) and with incident diabetes over 5 years follow-up. Concentrations of four species (Ceramide C16:0, C18:0, C20:0, and C22:0) were inversely associated with HOMA2-%S at baseline (all P values < 0.05, Q values < 0.05) and change in HOMA2-%S over 5 years (all P values < 0.05, Q values < 0.05). No sphingolipids were associated with baseline or change in DIo. Of the four species associated with HOMA2-%S, only Ceramide C18:0 was significantly and positively associated with incident diabetes (RR/1SD 1.44, 95 % CI 1.10-1.80, P = 0.006, Q = 0.024). The association of plasma Ceramide C18:0 with the risk of diabetes was partially mediated by change in HOMA2-%S between baseline and 5 years (mediation proportion: 61.5 %, 95 % CI 21.1%-212.5 %). CONCLUSION: Plasma Ceramide C18:0 was associated with higher risk of incident diabetes which was partially mediated through a decrease in insulin sensitivity between baseline and five years. Circulating Ceramide C18:0 could be a potential biomarker for identifying those at risk of developing diabetes.


Asunto(s)
Diabetes Mellitus , Resistencia a la Insulina , Femenino , Humanos , Masculino , Persona de Mediana Edad , Asiático , Ceramidas , Estudios Transversales , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/epidemiología , Esfingolípidos
3.
Arterioscler Thromb Vasc Biol ; 40(11): 2785-2793, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32878474

RESUMEN

OBJECTIVE: High plasma ceramide levels and ratios are associated with poor outcomes in individuals with cardiovascular disease; less is known about their relation to cerebral small vessel disease. We examined whether high plasma ceramide levels or ratios were associated with cerebral microbleeds (CMBs) and lacunes and whether associations differ by sex. Approach and Results: We included 548 participants enrolled in the MCSA (Mayo Clinic Study of Aging) with concurrent plasma ceramide assays and magnetic resonance imaging. CMBs were quantified on T2* magnetic resonance imaging and lacunes on T2 fluid-attenuated inversion recovery magnetic resonance imaging. Fasting plasma ceramides were assayed using liquid chromatography-electrospray ionization tandem mass spectrometry. We used logistic regression models adjusting for age, sex, hypertension, and diabetes mellitus to examine the relationship between ceramides and presence of a lacune; hurdle models were used for presence and number of CMBs. Each SD increase in the log ceramide C16:0/24:0 ratio was associated with greater odds of a CMB (odds ratio, 1.28 [95% CI, 1.01-1.64]). There was an interaction between sex and the ceramide C16:0/24:0 ratio (P=0.049). The association between this ratio and presence of a CMB was stronger for women (odds ratio, 1.87 [95% CI, 1.20-3.00]) than men (odds ratio, 1.09 [95% CI, 0.80-1.46]). Several ceramides and all ceramide ratios were associated with number of CMBs. We did not find associations between plasma ceramides and lacunes. CONCLUSIONS: In a population-based sample, the plasma ceramide C16:0/24:0 ratio was associated with CMBs and was stronger for women. Plasma ceramides are differentially associated with cerebral small vessel pathologies.


Asunto(s)
Ceramidas/sangre , Hemorragia Cerebral/sangre , Enfermedades de los Pequeños Vasos Cerebrales/sangre , Anciano , Anciano de 80 o más Años , Biomarcadores/sangre , Hemorragia Cerebral/diagnóstico por imagen , Enfermedades de los Pequeños Vasos Cerebrales/diagnóstico por imagen , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Pronóstico , Medición de Riesgo , Factores de Riesgo , Factores Sexuales
4.
Arterioscler Thromb Vasc Biol ; 39(11): 2431-2436, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31510790

RESUMEN

OBJECTIVE: Sphingolipids, including S1P (sphingosine-1-phosphate) and ceramides, have been associated with vascular tone, blood pressure regulation, cardiovascular outcomes, and mortality. However, the relationship between plasma sphingolipids and cerebrovascular disease has not been examined. We aimed to assess the cross-sectional association between plasma sphingolipids and white matter hyperintensity (WMH) volume, which is a marker of cerebrovascular disease. Approach and Results: We included 588 participants (302 men and 286 women), aged 60 to 93, enrolled in the population-based Mayo Clinic Study of Aging who had MRI and plasma sphingolipids at the same study visit. Fasting plasma was obtained, and ceramides and S1P were assayed using liquid chromatography-electrospray ionization tandem mass spectrometry. Fluid-attenuated inversion recovery was used to measure WMH volume, defined as percent total intracranial volume. We used linear regression to cross-sectionally examine the relationships between plasma sphingolipids and WMH; both were log-transformed. In multivariable analyses adjusting for age, sex, and hypertension, higher levels of ceramide C16:0 (b [95% CI]=0.24 [0.02-0.45]) and the ceramide ratios C16:0_24:0 (b [95% CI]=0.30 [0.12-0.48]) and C24:1_24:0 (b [95% CI]=0.24 [0.07-0.41]) were associated with a higher WMH volume. A higher ceramide score was also associated with higher WMH volume (b [95% CI]=0.03 (0.01-0.04]). We did not observe any association between S1P and WMH volume. CONCLUSIONS: Higher plasma ceramide C16:0 and 2 specific ceramide ratios (C16:0_24:0 and C24:1_24:0) are associated with greater WMH volumes, independent of hypertension, suggesting their utility for measurement of cerebrovascular disease.


Asunto(s)
Ceramidas/sangre , Trastornos Cerebrovasculares/patología , Lisofosfolípidos/sangre , Esfingosina/análogos & derivados , Sustancia Blanca/patología , Anciano , Anciano de 80 o más Años , Biomarcadores/sangre , Trastornos Cerebrovasculares/diagnóstico por imagen , Estudios Transversales , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Factores de Riesgo , Esfingosina/sangre , Sustancia Blanca/diagnóstico por imagen
5.
J Fish Biol ; 96(6): 1341-1348, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32162333

RESUMEN

Myeloid differentiation factor 88 (Myd88) plays an important role in both innate and adaptive immune response. In this study, the full-length complementary DNA (cDNA) of myd88 from Misgurnus anguillicaudatus was characterized. The myd88 cDNA is 1333 bp in length and contains an 855 bp open reading frame encoding a predicted protein of 284 amino acids. The predicted protein possesses typical Myd88 domain structural features including a death domain in the N-terminus, and box 1, 2, and 3 motifs of the Toll/IL-1 receptor domain in the C-terminus. Quantitative real-time PCR (qRT-PCR) revealed that myd88 messenger RNA (mRNA) was ubiquitously expressed in all examined tissues, especially highly in brain, kidney, blood, intestines and liver. qRT-PCR and western blotting were used to determine the mRNA and protein levels of Myd88 after Aeromonas veronii challenge, respectively. The Myd88 was remarkably upregulated in response to infection of A. veronii. These results suggested that Myd88 may play a vital role during the immune response of M. anguillicaudatus against bacterial infection.


Asunto(s)
Cipriniformes/genética , Cipriniformes/inmunología , Enfermedades de los Peces/inmunología , Infecciones por Bacterias Gramnegativas/veterinaria , Factor 88 de Diferenciación Mieloide/genética , Factor 88 de Diferenciación Mieloide/inmunología , Aeromonas veronii/inmunología , Animales , Clonación Molecular , ADN Complementario/genética , Infecciones por Bacterias Gramnegativas/inmunología , ARN Mensajero/metabolismo
6.
J Lipid Res ; 60(9): 1630-1639, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31227640

RESUMEN

The de novo ceramide synthesis pathway is essential to human biology and health, but genetic influences remain unexplored. The core function of this pathway is the generation of biologically active ceramide from its precursor, dihydroceramide. Dihydroceramides have diverse, often protective, biological roles; conversely, increased ceramide levels are biomarkers of complex disease. To explore the genetics of the ceramide synthesis pathway, we searched for deleterious nonsynonymous variants in the genomes of 1,020 Mexican Americans from extended pedigrees. We identified a Hispanic ancestry-specific rare functional variant, L175Q, in delta 4-desaturase, sphingolipid 1 (DEGS1), a key enzyme in the pathway that converts dihydroceramide to ceramide. This amino acid change was significantly associated with large increases in plasma dihydroceramides. Indexes of DEGS1 enzymatic activity were dramatically reduced in heterozygotes. CRISPR/Cas9 genome editing of HepG2 cells confirmed that the L175Q variant results in a partial loss of function for the DEGS1 enzyme. Understanding the biological role of DEGS1 variants, such as L175Q, in ceramide synthesis may improve the understanding of metabolic-related disorders and spur ongoing research of drug targets along this pathway.


Asunto(s)
Ceramidas/biosíntesis , Ácido Graso Desaturasas/genética , Western Blotting , Sistemas CRISPR-Cas/genética , Ceramidas/metabolismo , Femenino , Genotipo , Células Hep G2 , Humanos , Masculino , Americanos Mexicanos
7.
J Biol Chem ; 293(47): 18328-18336, 2018 11 23.
Artículo en Inglés | MEDLINE | ID: mdl-30305392

RESUMEN

2-Hydroxy-oleic acid (2OHOA) is a potent anticancer drug that induces cancer cell cycle arrest and apoptosis. Previous studies have suggested that 2OHOA's anticancer effect is mediated by SMS activation in cancer cells, including A549 and U118 cells. To confirm this phenomenon, in this study, we treated both A549 and U118 cells with 2OHOA and measured SMS activity. To our surprise, we found neither 2OHOA-mediated SMS activation nor sphingomyelin accumulation in the cells. However, we noted that 2OHOA significantly reduces phosphatidylcholine in these cells. We also did not observe 2OHOA-mediated SMS activation in mouse tissue homogenates. Importantly, 2OHOA inhibited rather than activated recombinant SMS1 (rSMS1) and rSMS2 in a dose-dependent fashion. Intra-gastric treatment of C57BL/6J mice with 2OHOA for 10 days had no effects on liver and small intestine SMS activities and plasma sphingomyelin levels. The treatment inhibited lysophosphatidylcholine acyltransferase (LPCAT) activity, consistent with the aforementioned reduction in plasma phosphatidylcholine. Because total cellular phosphatidylcholine is used as a predictive biomarker for monitoring tumor responses, the previously reported 2OHOA-mediated cancer suppression could be related to this phosphatidylcholine reduction, which may influence cell membrane structure and properties. We conclude that 2OHOA is not a SMS activator and that its anticancer property may be related to an effect on phosphatidylcholine metabolism.


Asunto(s)
Antineoplásicos/metabolismo , Neoplasias/enzimología , Ácidos Oléicos/metabolismo , Transferasas (Grupos de Otros Fosfatos Sustitutos)/metabolismo , Animales , Antineoplásicos/administración & dosificación , Antineoplásicos/química , Línea Celular Tumoral , Activación Enzimática , Activadores de Enzimas/administración & dosificación , Activadores de Enzimas/química , Activadores de Enzimas/metabolismo , Humanos , Ratones , Ratones Endogámicos C57BL , Neoplasias/tratamiento farmacológico , Neoplasias/genética , Neoplasias/metabolismo , Ácidos Oléicos/administración & dosificación , Ácidos Oléicos/química , Fosfatidilcolinas/metabolismo , Esfingomielinas/metabolismo , Transferasas (Grupos de Otros Fosfatos Sustitutos)/química , Transferasas (Grupos de Otros Fosfatos Sustitutos)/genética
8.
J Lipid Res ; 59(7): 1164-1174, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29739864

RESUMEN

Elevated hepatic ceramide levels have been implicated in both insulin resistance (IR) and hepatic steatosis. To understand the factors contributing to hepatic ceramide levels in mice of both sexes, we have quantitated ceramides in a reference population of mice, the Hybrid Mouse Diversity Panel that has been previously characterized for a variety of metabolic syndrome traits. We observed significant positive correlations between Cer(d18:1/16:0) and IR/hepatic steatosis, consistent with previous findings, although the relationship broke down between sexes, as females were less insulin resistant, but had higher Cer(d18:1/16:0) levels than males. The sex difference was due in part to testosterone-mediated repression of ceramide synthase 6. One ceramide species, Cer(d18:1/20:0), was present at higher levels in males and was associated with IR only in males. Clear evidence of gene-by-sex and gene-by-diet interactions was observed, including sex-specific genome-wide association study results. Thus, our studies show clear differences in how hepatic ceramides are regulated between the sexes, which again suggests that the physiological roles of certain hepatic ceramides differ between the sexes.


Asunto(s)
Ceramidas/metabolismo , Dieta , Resistencia a la Insulina/genética , Resistencia a la Insulina/fisiología , Hígado/metabolismo , Caracteres Sexuales , Animales , Ceramidas/biosíntesis , Femenino , Hígado/efectos de los fármacos , Masculino , Ratones , Testosterona/farmacología
9.
J Viral Hepat ; 25(5): 535-542, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29274188

RESUMEN

It is unclear whether multiple nonstructural (NS) 5A resistance-associated substitutions (RASs) correlate with the outcome of sofosbuvir (SOF) and ledipasvir (LDV) therapy. We investigated the effects of multiple NS5A RASs in NS5A inhibitor-naïve patients with chronic hepatitis C virus genotype 1b infection treated with SOF/LDV. In 313 patients treated with SOF/LDV, we assessed the effects of multiple NS5A RASs on the sustained virological response (SVR). RASs at L28, R30, L31, Q54, P58, Q62, A92, and Y93 in the NS5A region were examined by direct sequencing. The prevalence of RASs was as follows: 2.6% at L28, 8.7% at R30, 6.1% at L31, 48.7% at Q54, 9.9% at P58, 9.9% at Q62, 5.1% at A92, 13.8% at Y93, and 19.2% at L31 or Y93. A total of 133 patients had no RASs. SVR was achieved in 98.7% of the patients. SVR rates significantly differed between patients with and without the L31 or Y93 RAS (93.0% [53/57] vs 100% [250/250], P = .0011). In addition, among patients with the L31 or Y93 RAS, 29.8%, 45.6% and 24.6% had one, two and three or more NS5A RASs, respectively. The SVR rate was significantly lower in patients with the L31 or Y93 RAS with more than three NS5A RASs compared to those with fewer than three NS5A RASs (71.4% [10/14] vs 100% [43/43], P = .0025). Although the prevalence of multiple NS5A RASs at baseline was low in NS5A inhibitor-naïve patients, the presence of multiple NS5A RASs was associated with the effectiveness of SOF/LDV therapy.


Asunto(s)
Antivirales/uso terapéutico , Bencimidazoles/uso terapéutico , Fluorenos/uso terapéutico , Hepacivirus/genética , Hepatitis C Crónica/tratamiento farmacológico , Mutación Missense , Sofosbuvir/uso terapéutico , Proteínas no Estructurales Virales/genética , Adulto , Anciano , Anciano de 80 o más Años , Farmacorresistencia Viral , Femenino , Genotipo , Hepacivirus/clasificación , Hepatitis C Crónica/virología , Humanos , Masculino , Persona de Mediana Edad , Análisis de Secuencia de ADN , Respuesta Virológica Sostenida , Resultado del Tratamiento , Proteínas no Estructurales Virales/antagonistas & inhibidores
10.
Anal Biochem ; 547: 66-76, 2018 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-29470948

RESUMEN

Phosphatidylinositol (3,4,5) trisphosphate (PIP3) is a biologically active membrane phospholipid that is essential for the growth and survival of all eukaryotic cells. We describe a new method that directly measures PIP3 and describe the HPLC separation and measurement of the positional isomers of phosphatidylinositol bisphosphate, PI(3,5)P2, PI(3,4)P2 and PI(4,5)P2. Mass spectrometric analyses were performed online using ultra-high performance liquid chromatography (UHPLC)-electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) in the negative multiple-reaction monitoring (MRM) modes. Rapid separation of PIP3 from PI, phosphatidylinositol phosphate (PIP) and PIP2 was accomplished by C18 reverse phase chromatography with the addition of the ion pairing reagents diisopropylethanolamine (DiiPEA) and ethylenediamine tetraacetic acid tetrasodium salt dihydrate (EDTA) to the samples and mobile phase with a total run time, including equilibration, of 12 min. Importantly, these chromatography conditions result in no carryover of PIP, PIP2, and PIP3 between samples. To validate the new method, U87MG cancer cells were serum starved and treated with PDGF to stimulate PIP3 biosynthesis in the presence or absence of the phosphatidylinositol 3-kinase (PI3K) inhibitor LY294002. Results generated with the LC/MS method were in excellent agreement with results generated using [33P] phosphate radiolabeled U87MG cells and anion exchange chromatography analysis, a well validated method for measuring PIP3. To demonstrate the usefulness of the new method, we generated reproducible IC50 data for several well-characterized PI3K small molecule inhibitors using a U87MG cell-based assay as well as showing PIP3 can be measured from additional cancer cell lines. Together, our results demonstrate this novel method is sensitive, reproducible and can be used to directly measure PIP3 without radiolabeling or complex lipid derivatization.


Asunto(s)
Fosfatos de Fosfatidilinositol/análisis , Fosfatos de Fosfatidilinositol/metabolismo , Espectrometría de Masa por Ionización de Electrospray/métodos , Línea Celular Tumoral , Cromatografía Liquida/métodos , Humanos
11.
Int J Clin Pract ; 72(1)2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28869721

RESUMEN

INTRODUCTION: Evidence linking sleep disruption and sexual dysfunction in men is mounting; yet the characterisation of sleep patterns and complaints utilising a clinically feasible method within this patient population remain largely under-reported. AIM: A pilot study aiming to demonstrate a clinically feasible method to characterise the sleep patterns and complaints in a representative sample of patients treated in a men's health clinic. METHODS: Male patients (n = 48) completed a battery of validated sleep questionnaires using an mHealth mobile platform, MySleepScript, at the Johns Hopkins Men's Health and Vitality Center. Metrics related to clinical feasibility such as completion time, ease of use, preference of electronic format, and patient satisfaction were also collected. MAIN OUTCOME MEASURES: Pittsburgh Sleep Quality Index (PSQI), Insomnia Severity Index (ISI), Berlin Questionnaire, Patient Health Questionnaire (PHQ-9), and Primary Care PTSD Screen (PC-PTSD). RESULTS: Primary urological chief symptoms for this sample patient population were erectile dysfunction (ED; 80%), hypogonadism (40%), benign prostatic hyperplasia/lower urinary tract symptoms (BPH/LUTS; 40%) and Peyronie's disease (10%). Mean PSQI score was 7.8 [SD 4.2], with 67% of all patients falling within the "poor sleeper" range. At least mild symptoms of depression were noted in 40% and 43% were at risk for obstructive sleep apnea (OSA) on the Berlin Questionnaire. CONCLUSIONS: This pilot study demonstrated the feasibility and potential utility of an mHealth platform to assist clinicians, within a men's health clinic, in detecting sleep disturbances. Disrupted sleep was revealed in well over half of this sample of patients. As a result of the growing evidence linking poor sleep and sleep disorders (eg, OSA) to the conditions relevant to men's health (eg, erectile dysfunction, hypogonadism and BPH), further efforts beyond this pilot study are necessary to identify the aetiological processes underlying the association between specific disrupted sleep disorders and urological conditions.


Asunto(s)
Salud del Hombre , Disfunciones Sexuales Fisiológicas/etiología , Disfunciones Sexuales Psicológicas/etiología , Trastornos del Sueño-Vigilia/diagnóstico , Telemedicina/métodos , Adulto , Anciano , Estudios Transversales , Estudios de Factibilidad , Humanos , Síntomas del Sistema Urinario Inferior/etiología , Masculino , Persona de Mediana Edad , Proyectos Piloto , Trastornos del Sueño-Vigilia/complicaciones , Encuestas y Cuestionarios
12.
South Med J ; 111(12): 758-762, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30512130

RESUMEN

OBJECTIVE: How outside factors affect physician decision making remains an open question of vital importance. We sought to investigate the importance of various influences on physician decision making when clinical guidelines differ from patient preference. METHODS: An online survey asking 469 primary care providers (PCPs) across four practice sites whether they would order magnetic resonance imaging for a patient with uncomplicated back pain. Participants were randomized to one of four scenarios: a patient's preference for imaging (control), a patient's preference plus a colleague's opinion against imaging (colleague), a patient's preference plus a professional society's recommendation against imaging (profession), or a patient's preference plus an accountable care organization's quality metric that measures physician use of imaging (ACO). Demographic information and the reasoning behind participants' decisions also were obtained. RESULTS: A total of 168 PCPs completed the survey, yielding a 36% completion rate. A majority chose not to pursue imaging: control 68%, colleague 85%, profession 87%, and ACO 78%. Multivariate logistic regression revealed that participants were more likely not to order advanced imaging only when reminded of a professional society recommendation (P = 0.017). Regression also suggested that practice site exerted an effect on the primary outcome. Evidence-based medicine and clinical judgment were the most cited reasons for the decision. CONCLUSIONS: Our results reinforce the potential to leverage professional societies to advance evidence-based medicine and reduce unnecessary testing. At the same time, practice site appeared to exert influence, suggesting that these recommendations must be part of local institutional culture to be effective.


Asunto(s)
Actitud del Personal de Salud , Toma de Decisiones Clínicas/métodos , Dolor de la Región Lumbar/diagnóstico por imagen , Médicos de Atención Primaria , Pautas de la Práctica en Medicina , Atención Primaria de Salud/métodos , Adulto , Anciano , Estudios Transversales , Medicina Basada en la Evidencia , Femenino , Encuestas de Atención de la Salud , Humanos , Modelos Logísticos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Prioridad del Paciente , Guías de Práctica Clínica como Asunto , Sociedades Médicas , Procedimientos Innecesarios
13.
AAPS PharmSciTech ; 19(3): 971-977, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29302872

RESUMEN

Antibody-drug conjugates (ADCs) are an emerging class of biopharmaceuticals. As such, there are no specific guidelines addressing impurity limits and qualification requirements. The current ICH guidelines on impurities, Q3A (Impurities in New Drug Substances), Q3B (Impurities in New Drug Products), and Q6B (Specifications: Test Procedures and Acceptance Criteria for Biotechnological/Biological Products) do not adequately address how to assess small molecule impurities in ADCs. The International Consortium for Innovation and Quality in Pharmaceutical Development (IQ) formed an impurities working group (IWG) to discuss this issue. This white paper presents a strategy for evaluating the impact of small molecule impurities in ADCs. This strategy suggests a science-based approach that can be applied to the design of control systems for ADC therapeutics. The key principles that form the basis for this strategy include the significant difference in molecular weights between small molecule impurities and the ADC, the conjugation potential of the small molecule impurities, and the typical dosing concentrations and dosing schedule. The result is that exposure to small impurities in ADCs is so low as to often pose little or no significant safety risk.


Asunto(s)
Contaminación de Medicamentos , Inmunoconjugados/química , Peso Molecular
14.
J Biol Chem ; 291(14): 7651-60, 2016 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-26828064

RESUMEN

Lysophosphatidylcholine acyltransferase 3 (Lpcat3) is involved in phosphatidylcholine remodeling in the small intestine and liver. We investigated lipid metabolism in inducible intestine-specific and liver-specificLpcat3gene knock-out mice. We producedLpcat3-Flox/villin-Cre-ER(T2)mice, which were treated with tamoxifen (at days 1, 3, 5, and 7), to deleteLpcat3specifically in the small intestine. At day 9 after the treatment, we found that Lpcat3 deficiency in enterocytes significantly reduced polyunsaturated phosphatidylcholines in the enterocyte plasma membrane and reduced Niemann-Pick C1-like 1 (NPC1L1), CD36, ATP-binding cassette transporter 1 (ABCA1), and ABCG8 levels on the membrane, thus significantly reducing lipid absorption, cholesterol secretion through apoB-dependent and apoB-independent pathways, and plasma triglyceride, cholesterol, and phospholipid levels, as well as body weight. Moreover, Lpcat3 deficiency does not cause significant lipid accumulation in the small intestine. We also utilized adenovirus-associated virus-Cre to depleteLpcat3in the liver. We found that liver deficiency only reduces plasma triglyceride levels but not other lipid levels. Furthermore, there is no significant lipid accumulation in the liver. Importantly, small intestine Lpcat3 deficiency has a much bigger effect on plasma lipid levels than that of liver deficiency. Thus, inhibition of small intestine Lpcat3 might constitute a novel approach for treating hyperlipidemia.


Asunto(s)
1-Acilglicerofosfocolina O-Aciltransferasa/deficiencia , Membrana Celular/metabolismo , Enterocitos/metabolismo , Intestino Delgado/metabolismo , Metabolismo de los Lípidos , Hígado/metabolismo , Transportador 1 de Casete de Unión a ATP/genética , Transportador 1 de Casete de Unión a ATP/metabolismo , Transportador de Casete de Unión a ATP, Subfamilia G, Miembro 8 , Transportadoras de Casetes de Unión a ATP/genética , Transportadoras de Casetes de Unión a ATP/metabolismo , Animales , Antígenos CD36/genética , Antígenos CD36/metabolismo , Membrana Celular/genética , Lipoproteínas/genética , Lipoproteínas/metabolismo , Proteínas de Transporte de Membrana/genética , Proteínas de Transporte de Membrana/metabolismo , Ratones , Ratones Noqueados , Especificidad de Órganos
15.
Hepatology ; 64(6): 2089-2102, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27642075

RESUMEN

Serine palmitoyltransferase is the key enzyme in sphingolipid biosynthesis. Mice lacking serine palmitoyltransferase are embryonic lethal. We prepared liver-specific mice deficient in the serine palmitoyltransferase long chain base subunit 2 gene using an albumin-cyclization recombination approach and found that the deficient mice have severe jaundice. Moreover, the deficiency impairs hepatocyte polarity, attenuates liver regeneration after hepatectomy, and promotes tumorigenesis. Importantly, we show that the deficiency significantly reduces sphingomyelin but not other sphingolipids in hepatocyte plasma membrane; greatly reduces cadherin, the major protein in adherens junctions, on the membrane; and greatly induces cadherin phosphorylation, an indication of its degradation. The deficiency affects cellular distribution of ß-catenin, the central component of the canonical Wnt pathway. Furthermore, such a defect can be partially corrected by sphingomyelin supplementation in vivo and in vitro. CONCLUSION: The plasma membrane sphingomyelin level is one of the key factors in regulating hepatocyte polarity and tumorigenesis. (Hepatology 2016;64:2089-2102).


Asunto(s)
Uniones Adherentes/fisiología , Carcinogénesis , Hígado/enzimología , Serina C-Palmitoiltransferasa/deficiencia , Factores de Edad , Animales , Ratones
16.
Gastroenterology ; 149(6): 1519-29, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26226572

RESUMEN

BACKGROUND & AIMS: Phosphatidylcholines (PCs) are structural and functional constituents of cell membranes. The activity of acyltransferase (lysophosphatidylcholine acyltransferase [LPCAT]) is required for addition of polyunsaturated fatty acids to the sn-2 position of PCs and is therefore required to maintain cell membrane structure and function. LPCAT3 is the most abundant isoform of LPCAT in the small intestine and liver, which are important sites of plasma lipoprotein metabolism. We investigated the effects of Lpcat3 disruption on lipid metabolism in mice. METHODS: We disrupted the gene Lpcat3 in C57BL/6J mice to create LPCAT3 knockout (KO) mice. Livers and small intestinal tissues were collected from LPCAT3 KO and C57BL/6J parental strain (controls), and levels of LPCAT messenger RNAs and protein were measured. Levels of lipids and lipoproteins were measured in plasma samples. We isolated enterocytes from mice and measured levels of RNAs and proteins involved in lipid uptake by real-time polymerase chain reaction and immunoblot assays, respectively. We assessed lipid absorption and PC subspecies in the enterocyte plasma membrane using liquid chromatography with tandem mass spectometry. RESULTS: LPCAT3 KO mice survived only 3 weeks after birth. Oil Red O staining showed that the control but not LPCAT3 KO mice accumulated lipids in the small intestine; levels of Niemann-Pick C1-like 1 (NPC1L1) and fatty acid transporter protein 4 (FATP4), which regulate lipid uptake, were greatly reduced in the small intestines of LPCAT3 KO mice. Oral administration of PC and olive oil allowed the LPCAT3 KO mice to survive with the same body weights as controls, but the KO mice had shorter and wider small-intestinal villi and longer and bigger small intestines. Plasma membranes of enterocytes from LPCAT3 KO mice also had significant reductions in the composition of polyunsaturated PCs and reduced levels of NPC1L1, CD36, and FATP4 proteins. These reductions were associated with reduced intestinal uptake of lipid by the small intestine and reduced plasma levels of cholesterol, phospholipid, and triglyceride. CONCLUSIONS: LPCAT3 KO mice have longer and larger small intestines than control mice, with shorter wide villi, reduced lipid absorption, and lower levels NPC1L1, CD36, and FATP4 proteins. Inhibition of LPCAT3 in the small intestine could be developed as an approach to treat hyperlipidemia.


Asunto(s)
1-Acilglicerofosfocolina O-Aciltransferasa/metabolismo , Enterocitos/metabolismo , Absorción Intestinal/fisiología , Mucosa Intestinal/patología , Intestino Delgado/metabolismo , Metabolismo de los Lípidos/fisiología , 1-Acilglicerofosfocolina O-Aciltransferasa/deficiencia , 1-Acilglicerofosfocolina O-Aciltransferasa/genética , Animales , Peso Corporal/fisiología , Antígenos CD36/metabolismo , Colesterol/sangre , Cromatografía Liquida , Proteínas de Transporte de Ácidos Grasos/metabolismo , Immunoblotting , Absorción Intestinal/genética , Mucosa Intestinal/metabolismo , Intestino Delgado/citología , Metabolismo de los Lípidos/genética , Hígado/metabolismo , Proteínas de Transporte de Membrana/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Aceite de Oliva/administración & dosificación , Fosfatidilcolinas/administración & dosificación , Fosfatidilcolinas/metabolismo , Fosfolípidos/metabolismo , ARN Mensajero , Reacción en Cadena en Tiempo Real de la Polimerasa , Espectrometría de Masas en Tándem , Triglicéridos/sangre
17.
J Pharmacol Exp Ther ; 359(1): 207-14, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27516465

RESUMEN

Autotaxin is a secreted enzyme that catalyzes the conversion of lysophosphatidyl choline into the bioactive lipid mediator lysophosphatidic acid (LPA). It is the primary enzyme responsible for LPA production in plasma. It is upregulated in inflammatory conditions and inhibition of autotaxin may have anti-inflammatory activity in a variety of inflammatory diseases. To determine the role of autotaxin and LPA in the pathophysiology of inflammatory disease states, we used a potent and orally bioavailable inhibitor of autotaxin that we have recently identified, and characterized it in mouse models of inflammation, inflammatory bowel disease (IBD), multiple sclerosis (MS), and visceral pain. Compound-1, a potent inhibitor of autotaxin with an IC50 of ∼2 nM, has good oral pharmacokinetic properties in mice and results in a substantial inhibition of plasma LPA that correlates with drug exposure levels. Treatment with the inhibitor resulted in significant anti-inflammatory and analgesic effects in the carrageenan-induced paw inflammation and acetic acid-induced visceral pain tests, respectively. Compound-1 also significantly inhibited disease activity score in the dextran sodium sulfate-induced model of IBD, and in the experimental autoimmune encephalomyelitis model of MS. In conclusion, the present study demonstrates the anti-inflammatory and analgesic properties of a novel inhibitor of autotaxin that may serve as a therapeutic option for IBD, MS, and pain associated with inflammatory states.


Asunto(s)
Analgésicos/farmacología , Antiinflamatorios/farmacología , Inhibidores Enzimáticos/farmacología , Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Esclerosis Múltiple/tratamiento farmacológico , Hidrolasas Diéster Fosfóricas/metabolismo , Administración Oral , Analgésicos/administración & dosificación , Analgésicos/farmacocinética , Analgésicos/uso terapéutico , Animales , Antiinflamatorios/administración & dosificación , Antiinflamatorios/farmacocinética , Antiinflamatorios/uso terapéutico , Disponibilidad Biológica , Modelos Animales de Enfermedad , Inhibidores Enzimáticos/administración & dosificación , Inhibidores Enzimáticos/farmacocinética , Inhibidores Enzimáticos/uso terapéutico , Femenino , Masculino , Ratones , Dolor Visceral/tratamiento farmacológico
19.
Water Sci Technol ; 72(7): 1072-81, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26398021

RESUMEN

Rapid socio-economic development in suburban areas of developing countries has induced changes in agricultural waste and nutrient management, resulting in water pollution. The study aimed at estimating agricultural nutrient cycles and their contribution to the water environment. A material flow model of nitrogen (N) and phosphorus (P) was developed focusing on agricultural activities from 1980 to 2010 in Trai hamlet, an agricultural watershed in Nhue-Day River basin, Vietnam. The model focused on the change in household management of human excreta and livestock excreta, and chemical fertilizer consumption. The results showed that the proportion of nutrients from compost/manure applied to paddy fields decreased from 85 to 41% for both N and P between 1980 and 2010. The nutrient inputs derived from chemical fertilizer decreased 6% between 1980 and 2000 for both N and P. Then, these nutrients increased 1.4 times for N and 1.2 times for P from 2000 to 2010. As of 2010, the total inputs to paddy fields have amounted to 435 kg-N/ha/year and 90 kg-P/ha/year. Of these nutrient inputs, 40% of N and 65% of P were derived from chemical fertilizer. Thirty per cent (30%) of total N input was discharged to the water bodies through agricultural runoff and 47% of total P input accumulated in soil.


Asunto(s)
Agricultura , Monitoreo del Ambiente/métodos , Fertilizantes/análisis , Ríos/química , Contaminantes Químicos del Agua/análisis , Agricultura/normas , Humanos , Estiércol/análisis , Modelos Teóricos , Nitrógeno/análisis , Fósforo/análisis , Suelo/normas , Vietnam
20.
Curr Opin Clin Nutr Metab Care ; 16(1): 76-82, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23164986

RESUMEN

PURPOSE OF REVIEW: The endothelial isoform of nitric oxide synthase (eNOS) is constitutively expressed but dynamically regulated by a number of factors. Building our knowledge of this regulation is necessary to understand and modulate the bioavailability of nitric oxide, central to the cardiovascular complications of diabetes and other diseases. This review will focus on the eNOS substrate (L-arginine), its cofactor (tetrahydrobiopterin), and mechanisms related to the uncoupling of eNOS activity. RECENT FINDINGS: The global arginine bioavailability ratio has been proposed as a biomarker reflective of L-arginine availability, arginase activity, and citrulline cycling, as all of these processes impact eNOS activity. The failure of oral supplementation of tetrahydrobiopterin to recouple eNOS has emphasized the importance of the tetrahydrobiopterin to dihydrobiopterin ratio. Identification of transporters for biopterin species as well as signals that regulate endogenous arginine production have provided insight for alternative strategies to raise endothelial tetrahydrobiopterin levels while reducing dihydrobiopterin and alter eNOS activity. Finally, new information about redox regulation of eNOS itself may point to ways of controlling oxidative stress in the vasculature. SUMMARY: Restoring proper eNOS activity is key to ameliorating or preventing cardiovascular complications of diabetes. Continued investigation is needed to uncover new means for maintaining endothelial nitric oxide bioavailability.


Asunto(s)
Arginina/metabolismo , Biopterinas/análogos & derivados , Diabetes Mellitus/fisiopatología , Óxido Nítrico/metabolismo , Biomarcadores/sangre , Biopterinas/metabolismo , Enfermedades Cardiovasculares/complicaciones , Enfermedades Cardiovasculares/fisiopatología , Diabetes Mellitus/enzimología , Endotelio Vascular/citología , Endotelio Vascular/metabolismo , Homeostasis , Humanos , Óxido Nítrico Sintasa de Tipo III/metabolismo , Estrés Oxidativo , Tetrahidrofolato Deshidrogenasa/metabolismo
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