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1.
Nat Immunol ; 21(5): 546-554, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32231300

RESUMEN

High-dose radiation activates caspases in tumor cells to produce abundant DNA fragments for DNA sensing in antigen-presenting cells, but the intrinsic DNA sensing in tumor cells after radiation is rather limited. Here we demonstrate that irradiated tumor cells hijack caspase 9 signaling to suppress intrinsic DNA sensing. Instead of apoptotic genomic DNA, tumor-derived mitochondrial DNA triggers intrinsic DNA sensing. Specifically, loss of mitochondrial DNA sensing in Casp9-/- tumors abolishes the enhanced therapeutic effect of radiation. We demonstrated that combining emricasan, a pan-caspase inhibitor, with radiation generates synergistic therapeutic effects. Moreover, loss of CASP9 signaling in tumor cells led to adaptive resistance by upregulating programmed death-ligand 1 (PD-L1) and resulted in tumor relapse. Additional anti-PD-L1 blockade can further overcome this acquired immune resistance. Therefore, combining radiation with a caspase inhibitor and anti-PD-L1 can effectively control tumors by sequentially blocking both intrinsic and extrinsic inhibitory signaling.


Asunto(s)
Antineoplásicos Inmunológicos/uso terapéutico , Caspasa 9/metabolismo , Inhibidores de Caspasas/uso terapéutico , Quimioradioterapia/métodos , Neoplasias Colorrectales/terapia , Ácidos Pentanoicos/uso terapéutico , Animales , Antígeno B7-H1/genética , Antígeno B7-H1/metabolismo , Caspasa 9/genética , Línea Celular Tumoral , Modelos Animales de Enfermedad , Resistencia a Antineoplásicos/genética , Femenino , Humanos , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Noqueados , Trasplante de Neoplasias , Transducción de Señal , Regulación hacia Arriba
2.
Proc Biol Sci ; 291(2015): 20232578, 2024 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-38228178

RESUMEN

In the silkmoth Bombyx mori, the role of male sensilla trichodea in pheromone detection is well established. Here we study the corresponding female sensilla, which contain two olfactory sensory neurons (OSNs) and come in two lengths, each representing a single physiological type. Only OSNs in medium trichoids respond to the scent of mulberry, the silkworm's exclusive host plant, and are more sensitive in mated females, suggesting a role in oviposition. In long trichoids, one OSN is tuned to (+)-linalool and the other to benzaldehyde and isovaleric acid, both odours emitted by silkworm faeces. While the significance of (+)-linalool detection remains unclear, isovaleric acid repels mated females and may therefore play a role in avoiding crowded oviposition sites. When we examined the underlying molecular components of neurons in female trichoids, we found non-canonical co-expression of Ir8a, the co-receptor for acid responses, and ORco, the co-receptor of odorant receptors, in long trichoids, and the unexpected expression of a specific odorant receptor in both trichoid sensillum types. In addition to elucidating the function of female trichoids, our results suggest that some accepted organizational principles of the insect olfactory system may not apply to the predominant sensilla on the antenna of female B. mori.


Asunto(s)
Monoterpenos Acíclicos , Bombyx , Hemiterpenos , Neuronas Receptoras Olfatorias , Ácidos Pentanoicos , Receptores Odorantes , Animales , Femenino , Bombyx/metabolismo , Sensilos/fisiología , Olfato , Neuronas Receptoras Olfatorias/metabolismo , Receptores Odorantes/metabolismo , Feromonas/metabolismo
3.
J Environ Manage ; 356: 120522, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38493645

RESUMEN

In the context of a circular bio-based economy, more public attention has been paid to the environmental sustainability of biodegradable bio-based plastics, particularly plastics produced using emerging biotechnologies, e.g. poly(3-hydroxybutyrate-co-3-hydroxyvalerate) or PHBV. However, this has not been thoroughly investigated in the literature. Therefore, this study aimed to address three aspects regarding the environmental impact of PHBV-based plastic: (i) the potential environmental benefits of scaling up pellet production from pilot to industrial scale and the environmental hotspots at each scale, (ii) the most favourable end-of-life (EOL) scenario for PHBV, and (iii) the environmental performance of PHBV compared to benchmark materials considering both the pellet production and EOL stages. Life cycle assessment (LCA) was implemented using Cumulative Exergy Extraction from the Natural Environment (CEENE) and Environmental Footprint (EF) methods. The results show that, firstly, when upscaling the PHBV pellet production from pilot to industrial scale, a significant environmental benefit can be achieved by reducing electricity and nutrient usage, together with the implementation of better practices such as recycling effluent for diluting feedstock. Moreover, from the circularity perspective, mechanical recycling might be the most favourable EOL scenario for short-life PHBV-based products, using the carbon neutrality approach, as the material remains recycled and hence environmental credits are achieved by substituting recyclates for virgin raw materials. Lastly, PHBV can be environmentally beneficial equal to or even to some extent greater than common bio- and fossil-based plastics produced with well-established technologies. Besides methodological choices, feedstock source and technology specifications (e.g. pure or mixed microbial cultures) were also identified as significant factors contributing to the variations in LCA of (bio)plastics; therefore, transparency in reporting these factors, along with consistency in implementing the methodologies, is crucial for conducting a meaningful comparative LCA.


Asunto(s)
Hidroxibutiratos , Ácidos Pentanoicos , Poliésteres , Polihidroxibutiratos , Biotecnología
4.
Molecules ; 29(9)2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38731399

RESUMEN

The antibacterial effects of a selection of volatile fatty acids (acetic, propionic, butyric, valeric, and caproic acids) relevant to anaerobic digestion were investigated at 1, 2 and 4 g/L. The antibacterial effects were characterised by the dynamics of Enterococcus faecalis NCTC 00775, Escherichia coli JCM 1649 and Klebsiella pneumoniae A17. Mesophilic anaerobic incubation to determine the minimum bactericidal concentration (MBC) and median lethal concentration of the VFAs was carried out in Luria Bertani broth at 37 °C for 48 h. Samples collected at times 0, 3, 6, 24 and 48 h were used to monitor bacterial kinetics and pH. VFAs at 4 g/L demonstrated the highest bactericidal effect (p < 0.05), while 1 g/L supported bacterial growth. The VFA cocktail was the most effective, while propionic acid was the least effective. Enterococcus faecalis NCTC 00775 was the most resistant strain with the VFAs MBC of 4 g/L, while Klebsiella pneumoniae A17 was the least resistant with the VFAs MBC of 2 g/L. Allowing a 48 h incubation period led to more log decline in the bacterial numbers compared to earlier times. The VFA cocktail, valeric, and caproic acids at 4 g/L achieved elimination of the three bacteria strains, with over 7 log10 decrease within 48 h.


Asunto(s)
Antibacterianos , Enterococcus faecalis , Ácidos Grasos Volátiles , Klebsiella pneumoniae , Pruebas de Sensibilidad Microbiana , Ácidos Grasos Volátiles/metabolismo , Ácidos Grasos Volátiles/farmacología , Antibacterianos/farmacología , Antibacterianos/química , Enterococcus faecalis/efectos de los fármacos , Enterococcus faecalis/crecimiento & desarrollo , Klebsiella pneumoniae/efectos de los fármacos , Klebsiella pneumoniae/crecimiento & desarrollo , Anaerobiosis , Escherichia coli/efectos de los fármacos , Escherichia coli/crecimiento & desarrollo , Propionatos/farmacología , Concentración de Iones de Hidrógeno , Ácidos Pentanoicos/farmacología
5.
Zhonghua Gan Zang Bing Za Zhi ; 32(4): 318-324, 2024 Apr 20.
Artículo en Zh | MEDLINE | ID: mdl-38733186

RESUMEN

Objective: To explore the antiviral activity of the small-molecule compound AM679 in hepatitis B virus (HBV) replication and infection cell models. Methods: The positive regulatory effect of AM679 on EFTUD2 expression was validated by qPCR and Western blotting. HepAD38 and HepG2-NTCP cells were treated with AM679 (0.5, 1, and 2 nmol/L). Negative control, positive control, and AM679 combined with the entecavir group were set up. HBV DNA intra-and extracellularly, as well as the expression levels of intracellular HBV total RNAs and 3.5kb-RNA changes, were detected with qPCR. Hepatitis B surface antigen (HBsAg) and hepatitis B e antigen (HBeAg) levels were measured in the cell supernatant by an enzyme-linked immunosorbent assay (ELISA). The t-test method was used for the statistical analysis of the mean difference between groups. Results: EFTUD2 mRNA and protein expression levels were significantly increased in HepAD38 and HepG2-NTCP cells following AM679 treatment, with a statistically significant difference (P < 0.001). Intra-and extracellular indicators such as HBV DNA, HBV RNAs, HBV 3.5kb-RNA, HBsAg, and HBeAg were decreased to varying degrees in both cell models, and the decrease in these indicators was more pronounced with the increase in AM679 concentration and prolonged treatment duration, while the combined use of AM679 and entecavir had a more significant antiviral effect. The HBV DNA inhibition rates in the supernatant of HepAD38 cells with the use of 2 nmol/L AM679 were 21% and 48% on days three and nine, respectively. The AM679 combined with the ETV treatment group had the most significant inhibitory effect (62%), with a P < 0.01. More active HBV replication was observed after silencing EFTUD2, while the antiviral activity of AM679 was significantly weakened. Conclusion: AM679 exerts anti-HBV activity in vitro by targeting the regulation of EFTUD2 expression.


Asunto(s)
Antivirales , Virus de la Hepatitis B , Replicación Viral , Humanos , Antivirales/farmacología , ADN Viral , Guanina/análogos & derivados , Células Hep G2 , Antígenos e de la Hepatitis B/metabolismo , Antígenos de Superficie de la Hepatitis B/metabolismo , Virus de la Hepatitis B/efectos de los fármacos , Replicación Viral/efectos de los fármacos , Indoles/química , Indoles/farmacología , Ácidos Pentanoicos/química , Ácidos Pentanoicos/farmacología , Factores de Elongación de Péptidos/antagonistas & inhibidores , Factores de Elongación de Péptidos/metabolismo , Ribonucleoproteína Nuclear Pequeña U5/antagonistas & inhibidores , Ribonucleoproteína Nuclear Pequeña U5/metabolismo
6.
Chem Senses ; 482023 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-37956399

RESUMEN

Masking unpleasant odors with pleasant-smelling odorants has a long history and is utilized in various industries, including perfumery and consumer products. However, the effectiveness of odor masking is idiosyncratic and temporary. In this study, we employed Sniff olfactometry (SO) to investigate the psychophysics of masking using brief 70 ms stimulations with mixtures of the mal-odorant iso-valeric acid (IVA) and different masking agents. IVA is a component of human sweat that can overpower its smell and is often associated with unpleasant descriptors such as "gym locker," "smelly feet," "dirty clothes," and so on. Traditionally, high concentrations of pleasant-smelling odorants are used to mitigate the unpleasantness of IVA in situations involving clothing or environments contaminated with IVA. To examine the masking effects of sub-threshold levels of various masking agents (neohivernal, geraniol, florhydral, decanal, iso-longifolanone, methyl iso-eugenol, and s-limonene) on IVA, we conducted experiments using SO to measure the probability of recognizing IVA after 70 ms stimulations with headspaces containing mixtures of super-threshold concentrations of IVA and sub-threshold concentrations of IVA suppressors. The study involved nine subjects, and on average, a single masking agent was found to decrease IVA recognition probability by 14-72%. Moreover, a sub-threshold odor mixture consisting of 6 masking agents demonstrated a substantial decrease in IVA recognition, with a reduction of 96%.


Asunto(s)
Odorantes , Olfato , Humanos , Ácidos Pentanoicos , Olfatometría
7.
Int J Mol Sci ; 24(24)2023 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-38139077

RESUMEN

This review presents a comprehensive update of the biopolymer poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), emphasizing its production, properties, and applications. The overall biosynthesis pathway of PHBV is explored in detail, highlighting recent advances in production techniques. The inherent physicochemical properties of PHBV, along with its degradation behavior, are discussed in detail. This review also explores various blends and composites of PHBV, demonstrating their potential for a range of applications. Finally, the versatility of PHBV-based materials in multiple sectors is examined, emphasizing their increasing importance in the field of biodegradable polymers.


Asunto(s)
Poliésteres , Polímeros , Ácido 3-Hidroxibutírico , Poliésteres/química , Ácidos Pentanoicos
8.
Int J Mol Sci ; 24(3)2023 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-36768593

RESUMEN

Natural product-based structural templates have immensely shaped small molecule drug discovery, and new biogenic natural products have randomly provided the leads and molecular targets in anti-analgesic activity spheres. Pain relief achieved through opiates and non-steroidal anti-inflammatory drugs (NSAIDs) has been under constant scrutiny owing to their tolerance, dependency, and other organs toxicities and tissue damage, including harm to the gastrointestinal tract (GIT) and renal tissues. A new, 3',4',6'-triacetylated-glucoside, 2-O-ß-D-(3',4',6'-tri-acetyl)-glucopyranosyl-3-methyl pentanoic acid was obtained from Ficus populifolia, and characterized through a detailed NMR spectroscopic analysis, i.e., 1H-NMR, 13C-DEPT-135, and the 2D nuclear magnetic resonance (NMR) correlations. The product was in silico investigated for its analgesic prowess, COX-2 binding feasibility and scores, drug likeliness, ADMET (absorption, distribution, metabolism, excretion, and toxicity) properties, possible biosystem's toxicity using the Discovery Studio®, and other molecular studies computational software programs. The glycosidic product showed strong potential as an analgesic agent. However, an in vivo evaluation, though at strong levels of pain-relieving action, was estimated on the compound's extract owing to the quantity and yield issues of the glycosidic product. Nonetheless, the F. populifolia extract showed the analgesic potency in eight-week-old male mice on day seven of the administration of the extract's dose in acetic acid-induced writhing and hot-plate methods. Acetic acid-induced abdominal writhing for all the treated groups decreased significantly (p < 0.0001), as compared to the control group (n = 6) by 62.9%, 67.9%, and 70.9% of a dose of 100 mg/kg (n = 6), 200 mg/kg (n = 6), and 400 mg/kg (n = 6), respectively. Similarly, using the analgesia meter, the reaction time to pain sensation increased significantly (p < 0.0001), as compared to the control (n = 6). The findings indicated peripheral and central-nervous-system-mediated analgesic action of the product obtained from the corresponding extract.


Asunto(s)
Ficus , Animales , Masculino , Ratones , Ácido Acético/uso terapéutico , Analgésicos/uso terapéutico , Ficus/química , Dolor/tratamiento farmacológico , Dolor/inducido químicamente , Extractos Vegetales/química , Ácidos Pentanoicos/química
9.
J Am Chem Soc ; 144(43): 20016-20024, 2022 11 02.
Artículo en Inglés | MEDLINE | ID: mdl-36256876

RESUMEN

Naturally produced, biodegradable polyhydroxyalkanoates (PHAs) promise more sustainable alternatives to nonrenewable/degradable plastics, but biological PHA's stereomicrostructures are strictly confined to isotactic (R)-polymers or copolymers of random sequences. Chemical synthesis via catalyzed ring-opening polymerization (ROP) of cyclic (di)esters offers expedient access to diverse PHA microstructures, including those with defined comonomer sequences and tacticities. However, the synthesis of alternating isotactic PHAs has not been achieved by the existing methodologies. Here, we report the design of unsymmetrically disubstituted eight-membered diolides (rac-8DLR1-R2) and their site- and stereoselective ROP with discrete chiral catalysts, enabling the synthesis of alternating isotactic PHAs, poly(3-hydroxybutyrate-alt-3-hydroxyvalerate) (alt-P3HBV) and poly(3-hydroxybutyrate-alt-3-hydroxyheptanoate) (alt-P3HBHp), with high to quantitative (>99%) alternation and isotacticity and Mn up to 113 kDa and D = 1.01. Physical properties of such PHAs are substantially determined by the degree of backbone sequence alternation and tacticity, ranging from amorphous to semi-crystalline materials. The alt-P3HBV shows significantly improved mechanical performance relative to the constituent homopolymers. Intriguingly, enantiomeric (R)-alt-P3HBV and (S)-alt-P3HBV, synthesized by kinetically resolved ROP of rac-8DLMe-Et, form a stereocomplex with a significantly enhanced Tm (by 53 °C), while the enantiomeric homopolymers do not form a stereocomplex.


Asunto(s)
Polihidroxialcanoatos , Polimerizacion , Ácido 3-Hidroxibutírico , Ácidos Pentanoicos
10.
Int Arch Allergy Immunol ; 183(4): 398-408, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34839288

RESUMEN

BACKGROUND: Short-chain fatty acids (SCFAs) are abundant bacterial metabolites in the gut, with immunomodulatory properties. Hence, they may influence allergy development. Previous studies have linked fecal SCFA pattern during infancy with allergy. However, the association of SCFAs to allergic outcomes in adolescence is not well established. Here, we examined how the fecal SCFA pattern at 1 year of age related to allergy at 13 years of age. METHODS: Levels of 8 SCFAs in fecal samples collected at 1 year of age from 110 children were quantified using gas chromatography. The same individuals were evaluated at 13 years of age for allergic symptoms, allergy diagnosis and allergy medication by questionnaire, and for sensitization using skin prick test against egg, milk, fish, wheat and soy, cat, dog, horse, birch, and timothy grass. RESULTS: The concentration of fecal valeric acid at 1 year of age was inversely associated with eczema at 13 years of age (OR 0.6, 95% CI: 0.4-1.0, p = 0.049) and showed a trend for inverse association with food allergy at 13 years of age (OR 0.6, 95% CI: 0.4-1.0, p = 0.057). In a sub-group analysis of children with eczema at 1 year of age, a higher concentration of fecal valeric acid was linked with reduced risk of their eczema remaining at 13 years of age (OR 0.2, 95% CI: 0.0-1.5), although this latter analysis did not reach statistical significance (p = 0.12). CONCLUSIONS: Our findings lend further support to the notion of early childhood as a critical period when allergy may be programmed via the gut microbiota. Higher levels of fecal valeric acid may be characteristic of a protective gut microbiota and/or actively contribute to protection from eczema and food allergy.


Asunto(s)
Eccema , Hipersensibilidad a los Alimentos , Animales , Cohorte de Nacimiento , Preescolar , Perros , Eccema/epidemiología , Hipersensibilidad a los Alimentos/epidemiología , Caballos , Humanos , Lactante , Ácidos Pentanoicos , Suecia/epidemiología
11.
Mol Psychiatry ; 26(12): 7167-7187, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34663905

RESUMEN

Postoperative cognitive dysfunction (POCD) affects the outcome of millions of patients each year. Aging is a risk factor for POCD. Here, we showed that surgery induced learning and memory dysfunction in adult mice. Transplantation of feces from surgery mice but not from control mice led to learning and memory impairment in non-surgery mice. Low intensity exercise improved learning and memory in surgery mice. Exercise attenuated surgery-induced neuroinflammation and decrease of gut microbiota diversity. These exercise effects were present in non-exercise mice receiving feces from exercise mice. Exercise reduced valeric acid, a gut microbiota product, in the blood. Valeric acid worsened neuroinflammation, learning and memory in exercise mice with surgery. The downstream effects of exercise included attenuating growth factor decrease, maintaining astrocytes in the A2 phenotypical form possibly via decreasing C3 signaling and improving neuroplasticity. Similar to these results from adult mice, exercise attenuated learning and memory impairment in old mice with surgery. Old mice receiving feces from old exercise mice had better learning and memory than those receiving control old mouse feces. Surgery increased blood valeric acid. Valeric acid blocked exercise effects on learning and memory in old surgery mice. Exercise stabilized gut microbiota, reduced neuroinflammation, attenuated growth factor decrease and preserved neuroplasticity in old mice with surgery. These results provide direct evidence that gut microbiota alteration contributes to POCD development. Valeric acid is a mediator for this effect and a potential target for brain health. Low intensity exercise stabilizes gut microbiota in the presence of insult, such as surgery.


Asunto(s)
Disfunción Cognitiva , Disbiosis , Condicionamiento Físico Animal , Procedimientos Quirúrgicos Operativos/efectos adversos , Animales , Cognición , Disfunción Cognitiva/etiología , Ratones , Ratones Endogámicos C57BL , Plasticidad Neuronal , Ácidos Pentanoicos
12.
Environ Res ; 215(Pt 1): 114323, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36115419

RESUMEN

Dependency on plastic commodities has led to a recurrent increase in their global production every year. Conventionally, plastic products are derived from fossil fuels, leading to severe environmental concerns. The recent coronavirus disease 2019 pandemic has triggered an increase in medical waste. Conversely, it has disrupted the supply chain of personal protective equipment (PPE). Valorisation of food waste was performed to cultivate C. necator for fermentative production of biopolymer poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV). The increase in biomass, PHBV yield and molar 3-hydroxy valerate (3HV) content was estimated after feeding volatile fatty acids. The fed-batch fermentation strategy reported in this study produced 15.65 ± 0.14 g/L of biomass with 5.32 g/L of PHBV with 50% molar 3HV content. This is a crucial finding, as molar concentration of 3HV can be modulated to suit the specification of biopolymer (film or fabric). The strategy applied in this study addresses the issue of global food waste burden and subsequently generates biopolymer PHBV, turning waste to wealth.


Asunto(s)
COVID-19 , Cupriavidus necator , Residuos Sanitarios , Eliminación de Residuos , Biopolímeros , Cupriavidus necator/metabolismo , Fermentación , Alimentos , Combustibles Fósiles , Humanos , Hidroxibutiratos , Ácidos Pentanoicos , Plásticos , Poliésteres , Valeratos
13.
Bioprocess Biosyst Eng ; 45(8): 1331-1347, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35792928

RESUMEN

The domination of high-cost organic acids over other 3-hydroxyvalerate (3HV) precursors due to the wide preference among polyhydroxyalkanoates (PHA)-producing bacteria has limited the development of diverse poly(3-hydroxybutyrate-co-3-hydroxyvalerate) [P(3HB-co-3HV)] production processes. 1-pentanol is a low-cost 3HV precursor but is rarely employed due to the relatively low tolerance among PHA-producing bacteria. This study demonstrated P(3HB-co-3HV) production with manipulable and reproducible 3HV composition and 3HV yield from palm olein and 1-pentanol. Cupriavidus malaysiensis USMAA2-4ABH16 is the transformant strain with acquired lipase genes that retains the high tolerance towards 1-pentanol of its wild-type, with a preference for 1-pentanol over valeric acid indicated by the sixfold higher 3HV yield than that from valeric acid. C. malaysiensis USMAA2-4ABH16 was able to tolerate up to 0.15 wt% C 1-pentanol. Upon optimization using response surface methodology, 0.41‒0.52 g/g P(3HB-co-3HV) yield and 72‒89 wt% PHA content was achieved for 7, 9, 12 and 16 mol% 3HV, with 3HV yields of 0.30 g/g, 0.26 g/g, 0.23 g/g and 0.23 g/g, respectively. Up-scaling batch production by adopting the optimized concentrations of substrates for 12 mol% 3HV resulted in reproducible 3HV composition and 3HV yield on a 120-fold larger scale. The P(3HB-co-12 mol% 3HV) produced displayed higher flexibility than polypropylene and P(3HB-co-3HV) produced from different carbon sources. C. malaysiensis USMAA2-4ABH16 could be practically applicable for sustainable and economically feasible P(3HB-co-3HV) production on an industrial scale from used palm olein with relatively similar oleic acid content with palm olein and 1-pentanol, with higher 3HV compositions achievable through fed-batch strategies owing to its high 1-pentanol tolerance.


Asunto(s)
Cupriavidus necator , Cupriavidus , Polihidroxialcanoatos , Carbono , Etanol , Hidroxibutiratos , Ácidos Pentanoicos , Poliésteres/química
14.
Molecules ; 27(19)2022 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-36234738

RESUMEN

Polyhydroxyalkanoates (PHAs) are a family of biopolyesters synthesized by various microorganisms. Due to their biocompatibility and biodegradation, PHAs have been proposed for biomedical applications, including tissue engineering scaffolds. Olive leaf extract (OLE) can be obtained from agri-food biowaste and is a source of polyphenols with remarkable antioxidant properties. This study aimed at incorporating OLE inside poly(hydroxybutyrate-co-hydroxyvalerate) (PHBHV) fibers via electrospinning to obtain bioactive bio-based blends that are useful in wound healing. PHBHV/OLE electrospun fibers with a size of 1.29 ± 0.34 µm were obtained. Fourier transform infrared chemical analysis showed a uniform surface distribution of hydrophilic -OH groups, confirming the presence of OLE in the electrospun fibers. The main OLE phenols were released from the fibers within 6 days. The biodegradation of the scaffolds in phosphate buffered saline was investigated, demonstrating an adequate stability in the presence of metalloproteinase 9 (MMP-9), an enzyme produced in chronic wounds. The scaffolds were preliminarily tested in vitro with HFFF2 fibroblasts and HaCaT keratinocytes, suggesting adequate cytocompatibility. PHBHV/OLE fiber meshes hold promising features for wound healing, including the treatment of ulcers, due to the long period of durability in an inflamed tissue environment and adequate cytocompatibility.


Asunto(s)
Polihidroxialcanoatos , Antioxidantes/farmacología , Hidroxibutiratos/farmacología , Metaloproteinasa 9 de la Matriz , Olea , Ácidos Pentanoicos , Fosfatos , Extractos Vegetales , Poliésteres/química , Polihidroxialcanoatos/química , Polifenoles , Estudios Prospectivos , Ingeniería de Tejidos , Andamios del Tejido/química , Cicatrización de Heridas
15.
J Cell Mol Med ; 25(9): 4287-4297, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33768674

RESUMEN

Osteoclasts (OCs) play important roles in bone remodelling and contribute to bone loss by increasing bone resorption activity. Excessively activated OCs cause diverse bone disorders including osteoporosis. Isovaleric acid (IVA), also known as 3-methylbutanoic acid is a 5-carbon branched-chain fatty acid (BCFA), which can be generated by bacterial fermentation of a leucine-rich diet. Here, we find that IVA suppresses differentiation of bone marrow-derived macrophages into OCs by RANKL. IVA inhibited the expression of OC-related genes. IVA-induced inhibitory effects on OC generation were attenuated by pertussis toxin but not by H89, suggesting a Gi -coupled receptor-dependent but protein kinase A-independent response. Moreover, IVA stimulates AMPK phosphorylation, and treatment with an AMPK inhibitor blocks IVA-induced inhibition of OC generation. In an ovariectomized mouse model, addition of IVA to the drinking water resulted in significant decrease of body weight gain and inhibited the expression of not only OC-related genes but also fusogenic genes in the bone tissue. IVA exposure also blocked bone destruction and OC generation in the bone tissue of ovariectomized mice. Collectively, the results demonstrate that IVA is a novel bioactive BCFA that inhibits OC differentiation, suggesting that IVA can be considered a useful material to control osteoclast-associated bone disorders, including osteoporosis.


Asunto(s)
Resorción Ósea/prevención & control , Diferenciación Celular , Hemiterpenos/farmacología , Osteoclastos/citología , Osteoporosis/prevención & control , Ovariectomía/efectos adversos , Ácidos Pentanoicos/farmacología , Animales , Remodelación Ósea , Resorción Ósea/etiología , Resorción Ósea/patología , Femenino , Macrófagos/citología , Macrófagos/efectos de los fármacos , Ratones , Ratones Endogámicos C57BL , Osteoclastos/efectos de los fármacos , Osteoporosis/patología , Osteoporosis/cirugía , Transducción de Señal
16.
J Neurochem ; 158(5): 1074-1082, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34273193

RESUMEN

Imbalance in the metabolic pathway linking excitatory and inhibitory neurotransmission has been implicated in multiple psychiatric and neurologic disorders. Recently, we described enantiomer-specific effects of 2-methylglutamate, which is not decarboxylated to the corresponding methyl analogue of gamma-aminobutyric acid (GABA): 4-aminopentanoic acid (4APA). Here, we tested the hypothesis that 4APA also has enantiomer-specific actions in brain. Mouse cerebral synaptosome uptake (nmol/mg protein over 30 min) of (R)-4APA or (S)-4APA was time and temperature dependent; however, the R enantiomer had greater uptake, reduction of endogenous GABA concentration, and release following membrane depolarization than did the S enantiomer. (S)-4APA exhibited some weak agonist (GABAA α4ß3δ, GABAA α5ß2γ2, and GABAB B1/B2) and antagonist (GABAA α6ß2γ2) activity while (R)-4APA showed weak agonist activity only with GABAA α5ß2γ2. Both 4APA enantiomers (100 mg/kg IP) were detected in mouse brain 10 min after injection, and by 1 hr had reached concentrations that were stable over 6 hr; both enantiomers were cleared rapidly from mouse serum over 6 hr. Two-month-old mice had no mortality following 100-900 mg/kg IP of each 4APA enantiomer but did have similar dose-dependent reduction in distance moved in a novel cage. Neither enantiomer at 30 or 100 mg/kg impacted outcomes in 23 measures of well-being, activity chamber, or withdrawal from hot plate. Our results suggest that enantiomers of 4APA are active in mouse brain, and that (R)-4APA may act as a novel false neurotransmitter of GABA. Future work will focus on disease models and on possible applications as neuroimaging agents.


Asunto(s)
Conducta Exploratoria/fisiología , Locomoción/fisiología , Neurotransmisores/química , Ácidos Pentanoicos/química , Ácido gamma-Aminobutírico/química , Animales , Encéfalo/metabolismo , Química Encefálica , Relación Dosis-Respuesta a Droga , Conducta Exploratoria/efectos de los fármacos , Locomoción/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos C57BL , Neurotransmisores/metabolismo , Ácidos Pentanoicos/metabolismo , Ácidos Pentanoicos/farmacología , Receptores de GABA-A/química , Receptores de GABA-A/metabolismo , Estereoisomerismo , Sinaptosomas/metabolismo , Ácido gamma-Aminobutírico/metabolismo
17.
J Hepatol ; 74(2): 274-282, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33038432

RESUMEN

BACKGROUND & AIMS: Non-alcoholic steatohepatitis is a leading cause of end-stage liver disease. Hepatic steatosis and lipotoxicity cause chronic necroinflammation and direct hepatocellular injury resulting in cirrhosis, end-stage liver disease and hepatocellular carcinoma. Emricasan is a pan-caspase inhibitor that inhibits excessive apoptosis and inflammation; it has also been shown to decrease portal pressure and improve synthetic function in mice with carbon tetrachloride-induced cirrhosis. METHODS: This double-blind, placebo-controlled study randomized 217 individuals with decompensated NASH cirrhosis 1:1:1 to emricasan (5 mg or 25 mg) or placebo. Patients were stratified by decompensation status and baseline model for end-stage liver disease-sodium (MELD-Na) score. The primary endpoint comprised all-cause mortality, a new decompensation event (new or recurrent variceal hemorrhage, new ascites requiring diuretics, new unprecipitated hepatic encephalopathy ≥grade 2, hepatorenal syndrome, spontaneous bacterial peritonitis), or an increase in MELD-Na score ≥4 points. RESULTS: There was no difference in event rates between either of the emricasan treatment groups and placebo, with hazard ratios of 1.02 (95% CI 0.59-1.77; p = 0.94) and 1.28 (95% CI 0.75-2.21; p = 0.37) for 5 mg and 25 mg of emricasan, respectively. MELD-Na score progression was the most common outcome. There was no significant effect of emricasan treatment on MELD-Na score, international normalized ratio, total serum bilirubin, albumin level or Child-Pugh score. Emricasan was generally safe and well-tolerated. CONCLUSIONS: Emricasan was safe but ineffective for the treatment of decompensated NASH cirrhosis. However, this study may guide the design and conduct of future clinical trials in decompensated NASH cirrhosis. LAY SUMMARY: Patients with decompensated cirrhosis related to non-alcoholic steatohepatitis are at high risk of additional decompensation events and death. Post hoc analyses in previous pilot studies suggested that emricasan might improve portal hypertension and liver function. In this larger randomized study, emricasan did not decrease the number of decompensation events or improve liver function in patients with a history of decompensated cirrhosis related to non-alcoholic steatohepatitis. CLINICALTRIALS. GOV IDENTIFIER: NCT03205345.


Asunto(s)
Ascitis , Hemorragia Gastrointestinal , Encefalopatía Hepática , Cirrosis Hepática , Pruebas de Función Hepática/métodos , Enfermedad del Hígado Graso no Alcohólico , Ácidos Pentanoicos , Peritonitis , Ascitis/etiología , Ascitis/prevención & control , Inhibidores de Caspasas/administración & dosificación , Inhibidores de Caspasas/efectos adversos , Progresión de la Enfermedad , Monitoreo de Drogas/métodos , Enfermedad Hepática en Estado Terminal/etiología , Enfermedad Hepática en Estado Terminal/prevención & control , Várices Esofágicas y Gástricas/etiología , Várices Esofágicas y Gástricas/fisiopatología , Femenino , Hemorragia Gastrointestinal/etiología , Hemorragia Gastrointestinal/prevención & control , Encefalopatía Hepática/etiología , Encefalopatía Hepática/prevención & control , Humanos , Cirrosis Hepática/sangre , Cirrosis Hepática/tratamiento farmacológico , Cirrosis Hepática/etiología , Cirrosis Hepática/mortalidad , Masculino , Persona de Mediana Edad , Enfermedad del Hígado Graso no Alcohólico/complicaciones , Enfermedad del Hígado Graso no Alcohólico/diagnóstico , Ácidos Pentanoicos/administración & dosificación , Ácidos Pentanoicos/efectos adversos , Peritonitis/etiología , Peritonitis/prevención & control , Resultado del Tratamiento
18.
Liver Transpl ; 27(4): 568-579, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33164276

RESUMEN

Despite achieving sustained virologic response (SVR) to hepatitis C virus (HCV) therapy, there remains a post liver transplantation population with advanced fibrosis/cirrhosis. Emricasan is an orally active, pan-caspase inhibitor that suppresses apoptosis and inflammation, potentially decreasing hepatic inflammation and fibrosis. We aimed to determine the safety and efficacy of emricasan (IDN-6556-07) in a double-blind, randomized, placebo-controlled, multicenter study in reducing or preventing the progression of hepatic fibrosis in HCV liver transplant recipients with residual fibrosis or cirrhosis after achieving SVR. A total of 64 participants were randomly assigned to receive 25 mg twice daily of emricasan or placebo in a 2:1 ratio for 24 months. 41 participants were randomly assigned to emricasan and 23 to placebo; 32 participants in the emricasan group (78.0%) and 19 who took a placebo (82.6%) completed the study. There was no difference in the primary endpoint (Ishak fibrosis stages F2-F5, improvement in fibrosis or stability; Ishak fibrosis stage F6, improvement) between the emricasan (77.1%) and placebo groups (74.1%); P = NS. There was no difference between the emricasan (54.5%) and placebo (60.7%) arms in the rate of fibrosis improvement alone. However, those in the prespecified F3 to F5 subgroup had higher rates of stability or improvement in fibrosis in the emricasan group (95.2%) compared with placebo (54.6%) (P = 0.01). The tolerability and safety profiles were similar in both groups. In conclusion, overall stability in the Ishak fibrosis stage was similar between emricasan and placebo groups at 24 months. However, there was improvement and/or stability in fibrosis stage in the prespecified F3 to F5 subgroup with emricasan versus placebo, suggesting that patients with moderate fibrosis may benefit with emricasan.


Asunto(s)
Hepatitis C Crónica , Hepatitis C , Trasplante de Hígado , Antivirales/uso terapéutico , Método Doble Ciego , Fibrosis , Hepacivirus , Hepatitis C/tratamiento farmacológico , Hepatitis C Crónica/tratamiento farmacológico , Humanos , Cirrosis Hepática/tratamiento farmacológico , Trasplante de Hígado/efectos adversos , Ácidos Pentanoicos
19.
Biomacromolecules ; 22(7): 2935-2953, 2021 07 12.
Artículo en Inglés | MEDLINE | ID: mdl-34133120

RESUMEN

In the present study, three different newly developed copolymers of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) with 20, 40, and 60 mol % contents in 3-hydroxyvalerate (3HV) were produced by the biotechnological process of mixed microbial cultures (MMCs) using cheese whey (CW), a by-product from the dairy industry, as feedstock. The CW-derived PHBV copolyesters were first purified and then processed by solution electrospinning, yielding fibers of approximately 2 µm in cross-section in all cases. The resultant electrospun PHBV mats were, thereafter, post-processed by annealing at different temperatures, below their maximum of melting, selected according to their 3HV content in order to obtain continuous films based on coalesced fibers, so-called biopapers. The resultant PHBV films were characterized in terms of their morphology, crystallinity, and mechanical and barrier properties to assess their potential application in food packaging. The CW-derived PHBV biopapers showed high contact transparency but a slightly yellow color. The fibers of the 20 mol % 3HV copolymer were seen to contain mostly poly(3-hydroxybutyrate) (PHB) crystals, the fibers of the 40 mol % 3HV copolymer a mixture of PHB and poly(3-hydroxyvalerate) (PHV) crystals and lowest crystallinity, and the fibers of the 60 mol % 3HV sample were mostly made of PHV crystals. To understand the interfiber coalesce process undergone by the materials during annealing, the crystalline morphology was also assessed by variable-temperature both combined small-angle and wide-angle X-ray scattering synchrotron and Fourier transform infrared experiments. From these experiments and, different from previously reported biopapers with lower 3HV contents, all samples were inferred to have a surface energy reduction mechanism for interfiber coalescence during annealing, which is thought to be activated by a temperature-induced decrease in molecular order. Due to their reduced crystallinity and molecular order, the CW-derived PHBV biopapers, especially the 40 mol % 3HV sample, were found to be more ductile and tougher. In terms of barrier properties, the three copolymers performed similarly to water and limonene, but to oxygen, the 40 mol % sample showed the highest relative permeability. Overall, the materials developed, which are compatible with the Circular Bioeconomy organic recycling strategy, can have an excellent potential as barrier interlayers or coatings of application interest in food packaging.


Asunto(s)
Queso , Suero Lácteo , Hidroxibutiratos , Ácidos Pentanoicos , Poliésteres
20.
J Surg Res ; 259: 562-568, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33261858

RESUMEN

BACKGROUND: Gastroesophageal reflux and Barrett's esophagus are significant risk factors for the development of esophageal adenocarcinoma. Group IIa secretory phospholipase A2 (sPLA2) catalyzes the production of various proinflammatory metabolites and plays a critical role in promoting reflux-induced inflammatory changes within the distal esophagus. We hypothesized that inhibition of sPLA2 in human Barrett's cells would attenuate adhesion molecule expression via decreased activation of nuclear factor kappa B (NF-κB) and decrease cell proliferation, possibly mitigating the invasive potential of Barrett's esophagus. MATERIALS AND METHODS: Normal human esophageal epithelial cells (HET1A) and Barrett's cells (CPB) were assayed for baseline sPLA2 expression. CPB cells were treated with a specific inhibitor of sPLA2 followed by tumor necrosis factor-α. Protein expression was evaluated using immunoblotting. Cell proliferation was assessed using an MTS cell proliferation assay kit. Statistical analysis was performed using the Student's t-test or analysis of variance, where appropriate. RESULTS: CPB cells demonstrated higher baseline sPLA2 expression than HET1A cells (P = 0.0005). Treatment with 30 µM sPLA2 inhibitor significantly attenuated intercellular adhesion molecule-1 (P = 0.004) and vascular cell adhesion molecule-1 (P < 0.0001) expression as well as decreased NF-κB activation (P = 0.002). sPLA2 inhibition decreased cell proliferation in a dose-dependent manner (P < 0.001 for 15, 20, and 30 µM doses). CONCLUSIONS: sPLA2 inhibition in human Barrett's cells decreases cellular adhesive properties and NF-κB activation as well as decreases cell proliferation, signifying downregulation of the inflammatory response and possible attenuation of cellular malignant potential. These findings identify sPLA2 inhibition as a potential chemopreventive target for premalignant lesions of the esophagus.


Asunto(s)
Esófago de Barrett/patología , Esófago/patología , Fosfolipasas A2 Grupo II/antagonistas & inhibidores , Ácidos Pentanoicos/farmacología , Adenocarcinoma/patología , Adenocarcinoma/prevención & control , Esófago de Barrett/tratamiento farmacológico , Adhesión Celular/efectos de los fármacos , Línea Celular , Proliferación Celular/efectos de los fármacos , Evaluación Preclínica de Medicamentos , Neoplasias Esofágicas/patología , Neoplasias Esofágicas/prevención & control , Esófago/citología , Fosfolipasas A2 Grupo II/metabolismo , Humanos , Ácidos Pentanoicos/uso terapéutico
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