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1.
Int J Mol Sci ; 25(2)2024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-38279332

RESUMEN

Pollen cells require large amounts of sugars from the anther to support their development, which is critical for plant sexual reproduction and crop yield. Sugars Will Eventually be Exported Transporters (SWEETs) have been shown to play an important role in the apoplasmic unloading of sugars from anther tissues into symplasmically isolated developing pollen cells and thereby affect the sugar supply for pollen development. However, among the 17 CsSWEET genes identified in the cucumber (Cucumis sativus L.) genome, the CsSWEET gene involved in this process has not been identified. Here, a member of the SWEET gene family, CsSWEET5a, was identified and characterized. The quantitative real-time PCR and ß-glucuronidase expression analysis revealed that CsSWEET5a is highly expressed in the anthers and pollen cells of male cucumber flowers from the microsporocyte stage (stage 9) to the mature pollen stage (stage 12). Its subcellular localization indicated that the CsSWEET5a protein is localized to the plasma membrane. The heterologous expression assays in yeast demonstrated that CsSWEET5a encodes a hexose transporter that can complement both glucose and fructose transport deficiencies. CsSWEET5a can significantly rescue the pollen viability and fertility of atsweet8 mutant Arabidopsis plants. The possible role of CsSWEET5a in supplying hexose to developing pollen cells via the apoplast is also discussed.


Asunto(s)
Arabidopsis , Cucumis sativus , Arabidopsis/genética , Arabidopsis/metabolismo , Cucumis sativus/metabolismo , Proteínas de Transporte de Monosacáridos/genética , Proteínas de Transporte de Monosacáridos/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Hexosas/metabolismo , Polen/genética , Polen/metabolismo , Saccharomyces cerevisiae/metabolismo , Fertilidad/genética , Regulación de la Expresión Génica de las Plantas
2.
Prep Biochem Biotechnol ; 54(3): 343-357, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-37531084

RESUMEN

Microalgae are regarded as renewable resources of energy, foods and high-valued compounds using a biorefinery approach. In the present study, we explored isolated microalgae (Desmodesmus subspicatus) for the production of bio-energy molecules (carbohydrate and lipid). Optimizations of media (BG-11) components have been made using the Taguchi orthogonal array (TOA) technique to maximize biomass, carbohydrate and lipid production. Optimized results showed that biomass, carbohydrates and lipid productivity increased by 1.3 times at optimal combinations of media components than standard BG-11 media. Further, the influence of various carbon and nitrogen sources as nutritional supplement with optimum media composition under different light intensities was investigated for productivity of carbohydrate and lipid. Results demonstrated that 1.5 times higher productivity of carbohydrate and lipids were achieved in the presence optimum BG-11 under a broad range of light intensities (84-504 µmol m-2 s-1). Among different nitrogen sources, glycine was found to give higher productivity (1.5 times) followed by urea. Use of the cellulose as a carbon source in the media significantly increases biomass (2.4 times), carbohydrates (2.3 times) and lipids (2.3 times) productivity. Investigations revealed that cultivating Desmodesmus subspicatus under optimum culture conditions has the potential for large-scale bio-ethanol and bio-diesel production.


Asunto(s)
Celulosa , Microalgas , Carbono , Suplementos Dietéticos , Hexosas , Nitrógeno , Lípidos
3.
Plant J ; 113(2): 327-341, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36448213

RESUMEN

To cope with cold stress, plants have developed antioxidation strategies combined with osmoprotection by sugars. In potato (Solanum tuberosum) tubers, which are swollen stems, exposure to cold stress induces starch degradation and sucrose synthesis. Vacuolar acid invertase (VInv) activity is a significant part of the cold-induced sweetening (CIS) response, by rapidly cleaving sucrose into hexoses and increasing osmoprotection. To discover alternative plant tissue pathways for coping with cold stress, we produced VInv-knockout lines in two cultivars. Genome editing of VInv in 'Désirée' and 'Brooke' was done using stable and transient expression of CRISPR/Cas9 components, respectively. After storage at 4°C, sugar analysis indicated that the knockout lines showed low levels of CIS and maintained low acid invertase activity in storage. Surprisingly, the tuber parenchyma of vinv lines exhibited significantly reduced lipid peroxidation and reduced H2 O2 levels. Furthermore, whole plants of vinv lines exposed to cold stress without irrigation showed normal vigor, in contrast to WT plants, which wilted. Transcriptome analysis of vinv lines revealed upregulation of an osmoprotectant pathway and ethylene-related genes during cold temperature exposure. Accordingly, higher expression of antioxidant-related genes was detected after exposure to short and long cold storage. Sugar measurements showed an elevation of an alternative pathway in the absence of VInv activity, raising the raffinose pathway with increasing levels of myo-inositol content as a cold tolerance response.


Asunto(s)
Frío , Solanum tuberosum , beta-Fructofuranosidasa/genética , beta-Fructofuranosidasa/metabolismo , Metabolismo de los Hidratos de Carbono , Hexosas/metabolismo , Sacarosa/metabolismo , Solanum tuberosum/genética , Solanum tuberosum/metabolismo , Tubérculos de la Planta/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
4.
Carbohydr Res ; 522: 108696, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36335652

RESUMEN

Soft rot and blackleg diseases, caused by pectinolytic bacteria from the numerous species of Dickeya and Pectobacterium, pose a serious threat to the world potato production. Besides, infections triggered by these pectinolytic bacteria lead to huge economic losses in the cultivation of other crops, vegetables, and ornamentals. Strains belonging to the genus Pectobacterium tend to be isolated from various environments such as rotten or asymptomatic plants, weeds, soil or water. The main virulence factors of these phytopathogenic bacteria involve plant cell wall degrading enzymes (PCWDEs) i.e. pectinases, cellulases and proteases. Among accessory virulence factors, there is often lipopolysaccharide (LPS) listed. This constituent of the external part of bacterial cell wall contains lipid A, inner and outer core in addition to O-polysaccharide (OPS). LPS plays an important role in plant-microbe interactions, in particular during the first step of pathogen recognition. In this study we present the chemical structure of OPS of the first Pectobacterium aquaticum strain (IFB5637) isolated from water in Poland. The OPS consists of two common hexoses, such as mannose and glucose, as well as an abequose (3,6-dideoxy-d-xylo-hexose), the first 3,6-dideoxyhexose identified among the Pectobacteriaceae family: According to our best knowledge this is the first determined structure of the OPS of P. aquaticum.


Asunto(s)
Pectobacterium , Solanum tuberosum , Lipopolisacáridos , Enfermedades de las Plantas/microbiología , Hexosas , Solanum tuberosum/microbiología , Factores de Virulencia , Agua
5.
Sci Rep ; 12(1): 15390, 2022 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-36100614

RESUMEN

Reaumuria soongorica is an important biological barrier for ecological protection in the Gobi Desert in northwestern China, where soil nitrogen availability is low. N deposition has recently increased significantly in Gobi Desert, and the responses of R. soongorica to N enrichment may become a problem for ecological restoration and protection. However, little is known about the effects of N addition on the biomass, non-structural carbohydrates (NSC), and carbon:nitrogen:phosphorus (C:N:P) stoichiometry of R. soongorica in this region. Here, we examined changes in biomass, NSC and C:N:P ratios of different organs of R. soongorica seedlings in four N addition treatments: 0 (N0), 4.6 (N1), 9.2 (N2), and 13.8 (N3) g m-2 year-1. N addition up to 9.2 g m-2 year-1 significantly increased the biomass of different organs, simultaneously increasing the belowground: aboveground ratio of R. soongorica seedlings. Root NSC concentrations significantly increased under all N addition treatments, but leaf and stem NSC concentrations only increased under the N1 and N2 addition treatments. Nitrogen addition enhanced the soluble sugar concentrations (SSC) of leaves and roots, and reduced starch concentrations (SC) of all organs. Stem and root N concentrations significantly increased under the N2 and N3 treatments, and leaf N concentrations only increased under the N3 treatment, but N addition had no significant effect on plant C and P concentrations. Leaf and stem C:N ratios decreased significantly under the N2 and N3 treatments, but root C:N decreased significantly in all N addition treatments. The N3 treatment significantly increased the N:P ratio of all organs. N addition significantly enhanced available N (AN), available P (AP) and total phosphorus (TP) in rhizosphere soil. Our results suggest that N addition alters the biomass, NSC, N concentrations, C:N and N:P ratios of all plant organs, but roots responded more strongly than stems or leaves to N addition, potentially allowing the plants to absorb more water from the arid soil in this region ensuring the survival of R. soongorica seedlings. Rhizosphere soil AP, AN and TP concentrations were important factors affecting the NSC concentrations and stoichiometric characteristics of R. soongorica.


Asunto(s)
Plantones , Tamaricaceae , Carbohidratos , Hexosas , Nitrógeno , Fósforo , Suelo
6.
Molecules ; 27(16)2022 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-36014358

RESUMEN

Although sugar beets are primarily treated as a source of sucrose, due to their rich chemical composition, they can also be a source of other carbohydrates, e.g., mono- and oligosaccharides. The study focused on both fresh beet roots and those stored in mounds. Our studies have shown that, in addition to sucrose, sugar beet tissue also comprises other carbohydrates: kestose (3.39%) and galactose (0.65%) and, in smaller amounts, glucose, trehalose and raffinose. The acidic hydrolysis of the watery carbohydrates extracts resulted in obtaining significant amounts of glucose (8.37%) and arabinose (3.11%) as well as xylose and galactose and, in smaller amounts, mannose. An HPSEC liquid chromatography study of the molecular mass profile of the carbohydrate compounds present in the beet roots showed alongside the highest percentage (96.53-97.43%) of sucrose (0.34 kDa) the presence of pectin compounds from the araban group and arabinoxylooligosaccharides (5-9 kDa) with a percentage share of 0.61 to 1.87%. On the basis of our research, beet roots can be considered a potential source of carbohydrates, such as kestose, which is classified as fructooligosaccharide (FOS). The results of this study may be helpful in evaluating sugar beets as a direct source of various carbohydrates, or as a raw material for the biosynthesis of fructooligosaccharides (FOS) or galactooligosaccharides (GOS).


Asunto(s)
Beta vulgaris , Beta vulgaris/química , Carbohidratos/química , Galactosa , Glucosa , Hexosas , Oligosacáridos , Sacarosa , Verduras
7.
Plant Physiol ; 189(1): 344-359, 2022 05 03.
Artículo en Inglés | MEDLINE | ID: mdl-35166824

RESUMEN

Pollen fertility is critical for successful fertilization and, accordingly, for crop yield. While sugar unloading affects the growth and development of all types of sink organs, the molecular nature of sugar import to tomato (Solanum lycopersicum) pollen is poorly understood. However, sugar will eventually be exported transporters (SWEETs) have been proposed to be involved in pollen development. Here, reverse transcription-quantitative polymerase chain reaction (PCR) revealed that SlSWEET5b was markedly expressed in flowers when compared to the remaining tomato SlSWEETs, particularly in the stamens of maturing flower buds undergoing mitosis. Distinct accumulation of SlSWEET5b-ß-glucuronidase activities was present in mature flower buds, especially in anther vascular and inner cells, symplasmic isolated microspores (pollen grains), and styles. The demonstration that SlSWEET5b-GFP fusion proteins are located in the plasma membrane supports the idea that the SlSWEET5b carrier functions in apoplasmic sugar translocation during pollen maturation. This is consistent with data from yeast complementation experiments and radiotracer uptake, showing that SlSWEET5b operates as a low-affinity hexose-specific passive facilitator, with a Km of ∼36 mM. Most importantly, RNAi-mediated suppression of SlSWEET5b expression resulted in shrunken nucleus-less pollen cells, impaired germination, and low seed yield. Moreover, stamens from SlSWEET5b-silenced tomato mutants showed significantly lower amounts of sucrose (Suc) and increased invertase activity, indicating reduced carbon supply and perturbed Suc homeostasis in these tissues. Taken together, our findings reveal the essential role of SlSWEET5b in mediating apoplasmic hexose import into phloem unloading cells and into developing pollen cells to support pollen mitosis and maturation in tomato flowers.


Asunto(s)
Solanum lycopersicum , Flores/genética , Flores/metabolismo , Hexosas/metabolismo , Solanum lycopersicum/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Polen , Sacarosa/metabolismo
8.
Integr Cancer Ther ; 21: 15347354211073066, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35075934

RESUMEN

PURPOSE: Active hexose-correlated compound (AHCC), a standardized extract of cultured Lentinula edodes mycelia, exerts antitumor effects through anti-inflammatory and immune-modulatory functions. Adjuvant therapy for patients with hepatocellular carcinoma (HCC) who have undergone curative hepatectomy has not been established. The purpose of this study was to evaluate the efficacy and safety of AHCC as adjuvant therapy in patients with advanced HCC after curative hepatectomy. PATIENTS AND METHODS: The study design was single-armed, non-randomized, open (no one was blinded), and uncontrolled. Patients with HCC who underwent curative hepatectomy were treated with AHCC (1 g) 3 times daily orally for 2 years. The inclusion criteria were HCC diagnosed preoperatively as stages A and B of the Barcelona clinic liver cancer (BCLC) classification and alpha-fetoprotein × protein induced by vitamin K absence or antagonist II (PIVKA-II) ≥ 105 for stage A. RESULTS: A total of 29 patients were treated with AHCC, of which 25 (4 patients discontinued) were followed up. The 2-year recurrence-free survival rate after resection was 48% for those without discontinuations and 55.2% for all patients with a history of treatment. Serum albumin levels decreased to a minimum in the first postoperative month and gradually recovered to the preoperative level at 6 months. Almost no change in lymphocyte percentage was observed during follow-up. Inflammation-based prognostic scores were maintained at favorable levels after hepatectomy. Toxicity and adverse events were not observed in any patient. CONCLUSION: AHCC may be safe and effective in preventing HCC recurrence after curative hepatectomy, and further randomized trials of AHCC for its use in this setting are warranted.This clinical trial was registered in UMIN Clinical Trials Registry (ID UMIN000024396).


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Hongos Shiitake , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/cirugía , Hepatectomía , Hexosas/uso terapéutico , Humanos , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/cirugía , Recurrencia Local de Neoplasia/tratamiento farmacológico , Pronóstico , Estudios Retrospectivos
9.
Food Chem ; 369: 130943, 2022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-34469838

RESUMEN

This paper addresses sorbitan and sucrose ester in physical transformations of palm mid-fraction (PMF). Both emulsifiers influenced the crystallization properties of PMF, mainly due to emulsifier solubility, which affects its ability to interfere with the kinetics of solution-mediated phase transformations. DSC results corroborate the polymorphism analysis, indicating that the mechanism and rate of phase transformation depend on the chemical structure and amount of each emulsifier. The addition of sorbitan tristearate (STS) and sucrose stearate (S-370) increased the crystallization speed of the PMF and caused changes in the crystallization behavior. STS favored the ß'â†’ß transition, while S-370 stabilized the ß'-form. We can conclude that the presence of emulsifiers dissimilar to the composition of PMF modified its physical structure, either by increasing the liquid fraction or by reducing molecular motion, facilitating or preventing polymorphic transformations.


Asunto(s)
Estearatos , Sacarosa , Cristalización , Hexosas , Aceite de Palma , Sacarosa/análogos & derivados
10.
Pharmacol Rep ; 74(1): 135-147, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34739705

RESUMEN

BACKGROUND: Surface functionalization enhances the properties and characteristics of polymeric nanocapsules (NCs) mainly due to the surface charge, surfactants, and polymer coating type. Curcumin (CUR) is a bioactive compound with several proven pharmacological properties and low bioavailability. This study aimed to develop anionic (poly-ɛ-caprolactone; PCL) and cationic (Eudragit® RS100 (EUD)) NCs prepared with sorbitan monostearate (Span 60®) or sorbitan monooleate (Span 80®), coated with d-α-tocopherol polyethylene glycol 1000 succinate (TPGS) and optimized using 23 factorial analysis. Subsequently, the biological activity was evaluated. METHODS: A two-level, three-factor design (polymer, Span type, and TPGS concentration) was used. The biological effects of CUR-loaded TPGS-coated cationic and anionic NCs were assessed in apomorphine-induced stereotyped behavior in rats. RESULTS: The type of polymer (anionic or cationic) and Span® had a factorial influence on the physical and chemical characteristics of NCs according to the changes in TPGS concentrations. Both cationic and anionic CUR-NCs could block apomorphine-induced behavioral changes. CONCLUSIONS: The CUR-loaded TPGS-coated NCs proved to be a promising brain delivery system.


Asunto(s)
Apomorfina/farmacología , Conducta Animal/efectos de los fármacos , Curcumina/farmacología , Nanocápsulas/química , Conducta Estereotipada/efectos de los fármacos , Animales , Agonistas de Dopamina/farmacología , Inhibidores Enzimáticos , Hexosas/farmacología , Plantas Medicinales , Ratas , Resultado del Tratamiento , Vitamina E/farmacología
11.
J Trace Elem Med Biol ; 67: 126795, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34091240

RESUMEN

BACKGROUND: Atopic dermatitis (AD) is a multifactorial chronic inflammatory disease that affects ∼20 % of children and 3% of adults globally and is generally treated by the topical application of steroidal drugs that have undesirable side-effects. The development of alternative therapies is therefore an important objective. The present study investigated the effects of topical treatment with a novel water-soluble selenium-containing carbohydrate derivative (4-anhydro-4-seleno-D-tatitol, SeTal) on the symptoms and inflammatory parameters in an AD mouse model. METHODS: Mice were sensitized by applying 2,4-dinitrochlorobenzene (DNCB) to their dorsal skin on days 1-3, then further challenged on their ears and dorsal skin on days 14, 17, 20, 23, 26, and 29. SeTal (1 and 2%) or hydrocortisone (1%) was applied topically to the backs of the mice from days 14-29, and skin severity scores and scratching behavior determined on day 30. The mice were euthanized, and their ears and dorsal skin removed to quantify inflammatory parameters, edema, myeloperoxidase (MPO) activity, and AD-associated cytokines (tumor necrosis factor alpha (TNF-α), interleukins (IL)-18, and IL-33). RESULTS: DNCB treatment induced skin lesions and increased the scratching behavior, ear edema, MPO activity (ear and dorsal skin), and cytokine levels in dorsal skin. Topical application of SeTal improved inflammatory markers (cytokine levels and MPO activity), cutaneous severity scores, and scratching behavior. CONCLUSION: The efficacy of SeTal was satisfactory in the analyzed parameters, showing similar or better results than hydrocortisone. SeTal appears to be therapeutically advantageous for the treatment and control of AD.


Asunto(s)
Dermatitis Atópica , Animales , Citocinas , Dermatitis Atópica/inducido químicamente , Dermatitis Atópica/tratamiento farmacológico , Dinitroclorobenceno , Modelos Animales de Enfermedad , Hexosas , Hidrocortisona , Mediadores de Inflamación , Ratones , Ratones Endogámicos BALB C , Compuestos de Organoselenio , Piel
12.
NMR Biomed ; 34(7): e4511, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33772915

RESUMEN

Nucleotide sugars are required for the synthesis of glycoproteins and glycolipids, which play crucial roles in many cellular functions such as cell communication and immune responses. Uridine diphosphate-glucose (UDP-Glc) was previously believed to be the only nucleotide sugar detectable in brain by 31 P-MRS. Using spectra of high SNR and high resolution acquired at 7 T, we showed that multiple nucleotide sugars are coexistent in brain and can be measured simultaneously. In addition to UDP-Glc, these also include UDP-galactose (UDP-Gal), -N-acetyl-glucosamine (UDP-GlcNAc) and -N-acetyl-galactosamine (UDP-GalNAc), collectively denoted as UDP(G). Coexistence of these UDP(G) species is evident from a quartet-like multiplet at -9.8 ppm (M-9.8 ), which is a common feature seen across a wide age range (24-64 years). Lineshape fitting of M-9.8 allows an evaluation of all four UDP(G) components, which further aids in analysis of a mixed signal at -8.2 ppm (M-8.2 ) for deconvolution of NAD+ and NADH. For a group of seven young healthy volunteers, the concentrations of UDP(G) species were 0.04 ± 0.01 mM for UDP-Gal, 0.07 ± 0.03 mM for UDP-Glc, 0.06 ± 0.02 mM for UDP-GalNAc and 0.08 ± 0.03 mM for UDP-GlcNA, in reference to ATP (2.8 mM). The combined concentration of all UDP(G) species (average 0.26 ± 0.06 mM) was similar to the pooled concentration of NAD+ and NADH (average 0.27 ± 0.06 mM, with a NAD+ /NADH ratio of 6.7 ± 2.1), but slightly lower than previously found in an older cohort (0.31 mM). The in vivo NMR analysis of UDP-sugar composition is consistent with those from tissue extracts by other modalities in the literature. Given that glycosylation is dependent on the availability of nucleotide sugars, assaying multiple nucleotide sugars may provide valuable insights into potential aberrant glycosylation, which has been implicated in certain diseases such as cancer and Alzheimer's disease.


Asunto(s)
Encéfalo/diagnóstico por imagen , Hexosas/metabolismo , Espectroscopía de Resonancia Magnética , Uridina Difosfato Glucosa/metabolismo , Adenosina Trifosfato/metabolismo , Adulto , Femenino , Humanos , Masculino , NAD/metabolismo , Fósforo , Procesamiento de Señales Asistido por Computador , Uridina Difosfato Glucosa/síntesis química , Uridina Difosfato Glucosa/química , Adulto Joven
13.
Molecules ; 26(1)2021 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-33401775

RESUMEN

Hydrophobic curcumin in temulawak extract and hydrophilic betacyanin in red dragon fruit extract are high-value bioactive compounds with extensive applications in functional food. In this study, these extracts were encapsulated in water-in-oil-in-water (w/o/w) nanoemulsions as a delivery system using a two-step high-energy emulsification method. PGPR and Span 20 were used as lipophilic emulsifiers for the primary w/o emulsion. The most stable w/o/w formulation with the least oil phase separation of 5% v/v consisted of w/o emulsion (15% w/w) and Tween 80 (1.5% w/w) as hydrophilic emulsifier. The formulation was characterized by a 189-nm mean droplet diameter, 0.16 polydispersity index, and -32 mV zeta potential. The freeze-thaw stability may be attributed to the combination of low w/o emulsion content and high Tween 80 concentration in the outer water phase of the w/o/w nanoemulsions used in this study. The IC50 values of the nanoemulsion and the red dragon fruit extract were similar. It means that the higher concentration of curcumin in the nanoemulsions and the lower IC50 value of temulawak extract ensured sufficient antioxidant activities of the w/o/w nanoemulsions.


Asunto(s)
Cactaceae/química , Emulsiones/química , Nanoestructuras/química , Extractos Vegetales/química , Antioxidantes/química , Betacianinas/química , Aceite de Maíz/química , Curcuma/química , Curcumina/química , Sistemas de Liberación de Medicamentos , Emulsionantes/química , Congelación , Hexosas , Interacciones Hidrofóbicas e Hidrofílicas , Microscopía Electrónica de Transmisión , Polisorbatos/química , Espectroscopía Infrarroja por Transformada de Fourier , Agua/química
14.
Diabetologia ; 64(1): 181-194, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33052459

RESUMEN

AIMS/HYPOTHESIS: Melanocortin 4 receptor (MC4R) mutation is the most common cause of known monogenic obesity in humans. Unexpectedly, humans and rodents with MC4R deficiency do not develop hyperglycaemia despite chronic obesity and insulin resistance. To explain the underlying mechanisms for this phenotype, we determined the role of MC4R in glucose homeostasis in the presence and absence of obesity in mice. METHODS: We used global and hypothalamus-specific MC4R-deficient mice to investigate the brain regions that contribute to glucose homeostasis via MC4R. We performed oral, intraperitoneal and intravenous glucose tolerance tests in MC4R-deficient mice that were either obese or weight-matched to their littermate controls to define the role of MC4R in glucose regulation independently of changes in body weight. To identify the integrative pathways through which MC4R regulates glucose homeostasis, we measured renal and adrenal sympathetic nerve activity. We also evaluated glucose homeostasis in adrenaline (epinephrine)-deficient mice to investigate the role of adrenaline in mediating the effects of MC4R in glucose homeostasis. We employed a graded [13C6]glucose infusion procedure to quantify renal glucose reabsorption in MC4R-deficient mice. Finally, we measured the levels of renal glucose transporters in hypothalamus-specific MC4R-deficient mice and adrenaline-deficient mice using western blotting to ascertain the molecular mechanisms underlying MC4R control of glucose homeostasis. RESULTS: We found that obese and weight-matched MC4R-deficient mice exhibited improved glucose tolerance due to elevated glucosuria, not enhanced beta cell function. Moreover, MC4R deficiency selectively in the paraventricular nucleus of the hypothalamus (PVH) is responsible for reducing the renal threshold for glucose as measured by graded [13C6]glucose infusion technique. The MC4R deficiency suppressed renal sympathetic nerve activity by 50% in addition to decreasing circulating adrenaline and renal GLUT2 levels in mice, which contributed to the elevated glucosuria. We further report that adrenaline-deficient mice recapitulated the increased excretion of glucose in urine observed in the MC4R-deficient mice. Restoration of circulating adrenaline in both the MC4R- and adrenaline-deficient mice reversed their phenotype of improved glucose tolerance and elevated glucosuria, demonstrating the role of adrenaline in mediating the effects of MC4R on glucose reabsorption. CONCLUSIONS/INTERPRETATION: These findings define a previously unrecognised function of hypothalamic MC4R in glucose reabsorption mediated by adrenaline and renal GLUT2. Taken together, our findings indicate that elevated glucosuria due to low sympathetic tone explains why MC4R deficiency does not cause hyperglycaemia despite inducing obesity and insulin resistance. Graphical abstract.


Asunto(s)
Hexosas/metabolismo , Homeostasis/fisiología , Receptor de Melanocortina Tipo 4/fisiología , Bases de Schiff/metabolismo , Animales , Glucemia/metabolismo , Cruzamientos Genéticos , Epinefrina/deficiencia , Epinefrina/fisiología , Prueba de Tolerancia a la Glucosa , Transportador de Glucosa de Tipo 2/fisiología , Glucosuria/fisiopatología , Hipotálamo/química , Insulina/sangre , Resistencia a la Insulina/fisiología , Riñón/inervación , Riñón/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Obesidad/fisiopatología , Receptor de Melanocortina Tipo 4/deficiencia , Sistema Nervioso Simpático/fisiopatología
15.
Food Chem ; 334: 127561, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-32711272

RESUMEN

Grapefruit (Citrus paradisi) peel (GP) is rich in flavonoids and phenolics which have several proven pharmacological effects. However, their chemical instability towards oxygen, light and heat limits its applications in food industries. In the present study, we evaluated the feasibility of fabricating grapefruit-peel-phenolic (GPP) nano-emulsion in mustard oil using ultrasonication. Response surface methodology (RSM) optimization revealed that sonication time of 9.5 min at 30% amplitude and 0.52% Span-80 produced the stable GPP nano-emulsion with a droplet size of 29.73 ± 1.62 nm. Results indicate that both ultrasonication and Span-80 can assist the fabrication of a stabilized nano-emulsion. This study is one of its kind where nano-encapsulation of GPP into W/O emulsion was done to stabilize the active compound inside mustard oil and then the nano-emulsion was used to extend oxidative stability of mustard oil. Findings provide a basic guideline to formulate stable nano-emulsions for their use in active food packaging, oils, and pharmaceuticals.


Asunto(s)
Citrus paradisi/química , Emulsiones/química , Planta de la Mostaza/química , Nanoestructuras/química , Aceites de Plantas/química , Polifenoles/química , Antioxidantes/química , Almacenamiento de Alimentos , Frutas/química , Hexosas/química , Oxidación-Reducción , Sonicación
16.
Biochem Soc Trans ; 48(5): 2283-2293, 2020 10 30.
Artículo en Inglés | MEDLINE | ID: mdl-32897293

RESUMEN

Butanol is an important chemical and potential fuel. For more than 100 years, acetone-butanol-ethanol (ABE) fermentation of Clostridium strains has been the most successful process for biological butanol production. In recent years, other microbes have been engineered to produce butanol as well, among which Escherichia coli was the best one. Considering the crude oil price fluctuation, minimizing the cost of butanol production is of highest priority for its industrial application. Therefore, using cheaper feedstocks instead of pure sugars is an important project. In this review, we summarized butanol production from different renewable resources, such as industrial and food waste, lignocellulosic biomass, syngas and other renewable resources. This review will present the current progress in this field and provide insights for further engineering efforts on renewable butanol production.


Asunto(s)
Biocombustibles , Butanoles/metabolismo , Ingeniería Metabólica/métodos , Eliminación de Residuos/métodos , Acetona/metabolismo , Biomasa , Biotecnología/métodos , Butanoles/química , Carbono/química , Clostridium/metabolismo , Electrones , Escherichia coli/metabolismo , Etanol/metabolismo , Fermentación , Alimentos , Hexosas/química , Hidrólisis , Modelos Biológicos , Pentosas/química , Petróleo , Sacarosa/química , Biología Sintética
17.
Drug Deliv ; 27(1): 1342-1359, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32964732

RESUMEN

Presently, a combination of chemotherapy, radiotherapy, thermotherapy, and other treatments has become a hot topic of research for the treatment of cancer, especially lung cancer. In this study, novel hollow gold nanoparticles (HGNPs) were used as drug carriers, and in order to improve the targeting ability of HGNPs to a lung tumor site, polyoxyethylene sorbitol oleate (PSO) was chosen here as a target ligand since it can be specifically recognized by the low-density lipoprotein (LDL) receptor which is usually over expressed on A549 lung cancer cells. In this way, a PSO-modified doxorubicin-loaded HGNP drug delivery system (PSO-HGNPs-DOX) was constructed and its physicochemical properties, photothermal conversion ability, and drug release of PSO-HGNPs-DOX was investigated. Further, the effects of triple combination therapy, the intracellular uptake, and the ability to escape macrophage phagocytosis of PSO-HGNPs-DOX were also studied using A549 cells in vitro. In addition, an in vivo mouse model was also used to study the targeting of PSO-HGNPs-DOX to lung cancer. PSO-HGNPs-DOX demonstrated a good triple therapeutic effect for lung cancer (A549 cell viability was only 10% at 500 µM) by LDL receptor mediated endocytosis and was able to escape macrophage phagocytosis to enhance its accumulation at the target site. Therefore, PSO-HGNPs-DOX is a novel, safe, promising, and targeted drug carrier designed for triple combination lung cancer therapy which should be further studied for such applications.


Asunto(s)
Endocitosis/fisiología , Hexosas/administración & dosificación , Neoplasias Pulmonares/metabolismo , Macrófagos/metabolismo , Fagocitosis/fisiología , Receptores de LDL/metabolismo , Células A549 , Animales , Células Cultivadas , Relación Dosis-Respuesta a Droga , Endocitosis/efectos de los fármacos , Oro/administración & dosificación , Humanos , Neoplasias Pulmonares/terapia , Macrófagos/efectos de los fármacos , Nanopartículas del Metal/administración & dosificación , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Fagocitosis/efectos de los fármacos , Terapia Fototérmica/métodos , Polietilenglicoles/administración & dosificación , Ratas , Receptores de LDL/administración & dosificación , Ensayos Antitumor por Modelo de Xenoinjerto/métodos
18.
Drug Des Devel Ther ; 14: 3315-3324, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32884236

RESUMEN

INTRODUCTION: Ginsenoside Rh2, purified from the Panax ginseng root, has been demonstrated to possess anticancer properties against various cancerous cells including colorectal, breast, skin, ovarian, prostate, and liver cancerous cells. However, the poor bioavailability, low stability on gastrointestinal systems, and fast plasma elimination limit further clinical applications of Ginsenoside Rh2 for cancer treatments. In this study, a novel formulation of niosomal Ginsenoside Rh2 was prepared using the thin film hydration technique. METHODS: The niosomal formulation contained Span 60 and cholesterol, and cationic lipid DOTAP was evaluated by determining particle size distribution, encapsulation efficiency, the polydispersity index (PDI), and surface morphology. The cytotoxic effects of free Ginsenoside Rh2 and Ginsenoside Rh2-loaded niosomes were determined using the MTT method in the PC3 prostate cancer cell line. For the investigation of the in vitro cellular uptake of Ginsenoside Rh2-loaded niosome, two formulations were prepared: the Ginsenoside Rh2-loaded niosomal formula containing 5% DOTAP and the Ginsenoside Rh2-loaded niosomal formula without DOTAP. RESULTS: The mean size, DPI, zeta potential, and encapsulation efficiency of the Ginsenoside Rh2-loaded nanoniosomal formulation containing DOTAP were 93.5±2.1 nm, 0.203±0.01, +4.65±0.65, and 98.32% ±2.4, respectively. The niosomal vesicles were found to be round and have a smooth surface. The release profile of Ginsenoside Rh2 from niosome was biphasic. Furthermore, a two-fold reduction in the Ginsenoside Rh2 concentration was measured when Ginsenoside Rh2 was administered in a nanoniosomal form compared to free Ginsenoside Rh2 solutions in the PC3 prostate cancer cell line. After storage for 90 days, the encapsulation efficiency, vesicle size, PDI, and zeta potential of the optimized formulation did not significantly change compared to the freshly prepared samples. The cellular uptake experiments of the niosomal formulation demonstrated that by adding DOTAP to the niosomal formulation, the cellular uptake was enhanced. DISCUSSION: The enhanced cellular uptake and cytotoxic activity of the Ginsenoside Rh2 nanoniosomal formulation on the PC3 cell make it an attractive candidate for application as a nano-sized delivery vehicle to transfer Ginsenoside Rh2 to cancer cells.


Asunto(s)
Antineoplásicos/farmacología , Medicamentos Herbarios Chinos/farmacología , Ginsenósidos/farmacología , Neoplasias de la Próstata/tratamiento farmacológico , Antineoplásicos/química , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Colesterol/química , Composición de Medicamentos , Liberación de Fármacos , Ensayos de Selección de Medicamentos Antitumorales , Medicamentos Herbarios Chinos/química , Ácidos Grasos Monoinsaturados/química , Ginsenósidos/química , Hexosas/química , Humanos , Liposomas , Masculino , Células PC-3 , Panax/química , Tamaño de la Partícula , Neoplasias de la Próstata/patología , Compuestos de Amonio Cuaternario/química , Células Tumorales Cultivadas
19.
Ultrason Sonochem ; 69: 105258, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32702637

RESUMEN

O/W nanoemulsions are isotropic colloidal systems constituted of oil droplets dispersed in continuous aqueous media and stabilised by surfactant molecules. Nanoemulsions hold applications in more widespread technological domains, more crucially in the pharmaceutical industry. Innovative nanoemulsion-based drug delivery system has been suggested as a powerful alternative strategy through the useful means of encapsulating, protecting, and delivering the poorly water-soluble bioactive components. Consequently, there is a need to generate an emulsion with small and consistent droplets. Diverse studies acknowledged that ultrasonic cavitation is a feasible and energy-efficient method in making pharmaceutical-grade nanoemulsions. This method offers more notable improvements in terms of stability with a lower Ostwald ripening rate. Meanwhile, a microstructured reactor, for instance, microchannel, has further been realised as an innovative technology that facilitates combinatorial approaches with the acceleration of reaction, analysis, and measurement. The recent breakthrough that has been achieved is the controlled generation of fine and monodispersed multiple emulsions through microstructured reactors. The small inner dimensions of microchannel display properties such as short diffusion paths and high specific interfacial areas, which increase the mass and heat transfer rates. Hence, the combination of ultrasonic cavitation with microstructures (microchannel) provides process intensification of creating a smaller monodispersed nanoemulsion system. This investigation is vital as it will then facilitate the creation of new nanoemulsion based drug delivery system continuously. Following this, the fabrication of microchannel and setup of its combination with ultrasound was conducted in the generation of O/W nanoemulsion, as well as optimisation to analyse the effect of varied operating parameters on the mean droplet diameter and dispersity of the nanoemulsion generated, besides monitoring the stability of the nanoemulsion. Scanning transmission electron microscopy (STEM) images were also carried out for the droplet size measurements. In short, the outcomes of this study are encouraging, which necessitates further investigations to be carried out to advance a better understanding of coupling microchannel with ultrasound to produce pharmaceutical-grade nanoemulsions.


Asunto(s)
Emulsiones/química , Microquímica/instrumentación , Nanoestructuras/química , Aceite de Palma/química , Ultrasonido/métodos , Agua/química , Hexosas/química , Microquímica/métodos , Sonicación/métodos , Tensoactivos
20.
Biomolecules ; 10(7)2020 07 06.
Artículo en Inglés | MEDLINE | ID: mdl-32640594

RESUMEN

Aldose reductase (AKR1B1), the first enzyme in the polyol pathway, is likely involved in the onset of diabetic complications. Differential inhibition of AKR1B1 has been proposed to counteract the damaging effects linked to the activity of the enzyme while preserving its detoxifying ability. Here, we show that epigallocatechin gallate (EGCG), one of the most representative catechins present in green tea, acts as a differential inhibitor of human recombinant AKR1B1. A kinetic analysis of EGCG, and of its components, gallic acid (GA) and epigallocatechin (EGC) as inhibitors of the reduction of L-idose, 4-hydroxy2,3-nonenal (HNE), and 3-glutathionyl l-4-dihydroxynonanal (GSHNE) revealed for the compounds a different model of inhibition toward the different substrates. While EGCG preferentially inhibited L-idose and GSHNE reduction with respect to HNE, gallic acid, which was still active in inhibiting the reduction of the sugar, was less active in inhibiting HNE and GSHNE reduction. EGC was found to be less efficient as an inhibitor of AKR1B1 and devoid of any differential inhibitory action. A computational study defined different interactive modes for the three substrates on the AKR1B1 active site and suggested a rationale for the observed differential inhibition. A chromatographic fractionation of an alcoholic green tea extract revealed that, besides EGCG and GA, other components may exhibit the differential inhibition of AKR1B1.


Asunto(s)
Aldehído Reductasa/metabolismo , Catequina/análogos & derivados , Inhibidores Enzimáticos/farmacología , Té/química , Aldehído Reductasa/química , Dominio Catalítico/efectos de los fármacos , Catequina/química , Catequina/farmacología , Inhibidores Enzimáticos/química , Ácido Gálico/química , Ácido Gálico/farmacología , Glutatión/análogos & derivados , Glutatión/metabolismo , Hexosas/metabolismo , Humanos , Modelos Moleculares , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Extractos Vegetales/química , Extractos Vegetales/farmacología
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