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1.
Biochem Biophys Res Commun ; 630: 84-91, 2022 11 19.
Artículo en Inglés | MEDLINE | ID: mdl-36152349

RESUMEN

Milk lipids are an important energy source for infants, but the composition of milk lipids has not yet been clarified in detail. In this study, we analyzed free fatty acids and their metabolites in milk from humans and cows. In comparison to cow milk, human milk showed a higher content of free fatty acids including polyunsaturated fatty acids, especially ω-3 fatty acids and their metabolites. Polyunsaturated fatty acids were enriched at an early period of lactation, while saturated fatty acids did not change significantly over the period. Moreover, human milk contained high levels of ω-3 fatty acid metabolites, particularly 18-hydroxyeicosapentaenoic acid, an eicosapentaenoic acid-derived metabolite with anti-inflammatory activity. In comparison with human normal milk, thromboxane B2 and protectin D1 levels were significantly elevated in milk from individuals with mastitis, suggesting that these lipid mediators could be potential biomarkers of obstructive mastitis. Overall, the unique lipid profile of human milk supports the efficacy of breast-feeding for supply of more nutritional and bioactive lipids in comparison to artificial or cow milk to infants, in whom digestive and absorptive functions are still immature.


Asunto(s)
Ácidos Grasos Omega-3 , Mastitis , Animales , Biomarcadores/metabolismo , Bovinos , Eicosanoides/metabolismo , Ácido Eicosapentaenoico , Ácidos Grasos/metabolismo , Ácidos Grasos no Esterificados/metabolismo , Ácidos Grasos Omega-3/metabolismo , Ácidos Grasos Insaturados/metabolismo , Femenino , Humanos , Lactante , Lactancia/metabolismo , Mastitis/metabolismo , Leche/metabolismo , Leche Humana/metabolismo , Tromboxanos/metabolismo
2.
Molecules ; 24(2)2019 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-30650646

RESUMEN

We have previously found two novel monoterpene glycosides, liguroside A and liguroside B, with an inhibitory effect on the catalytic activity of the enzyme leukocyte-type 12-lipoxygenase in the Qing Shan Lu Shui tea. Here, two new monoterpene glycosides, liguroside C and liguroside D which inhibit this enzyme, were isolated from the same tea. The spectral and chemical evidence characterized the structures of these compounds as (5E)-7-hydroperoxy-3,7-dimethyl-1,5-octadienyl-3-O-(α-l-rhamnopyranosyl)-(1''→3')-(4'''-O-trans-p-coumaroyl)-ß-d-glucopyranoside and (2E)-6-hydroxy-3,7-dimethyl-2,7-octadienyl-3-O-(α-l-rhamnopyranosyl)-(1''→3')-(4'''-O-trans-p-coumaroyl)-ß-d-glucopyranoside, respectively. These ligurosides, which irreversibly inhibited leukocyte-type 12-lipoxygenase, have a hydroperoxy group in the monoterpene moiety. Additionally, monoterpene glycosides had the same backbone structure but did not have a hydroperoxy group, such as kudingoside A and lipedoside B-III, contained in the tea did not inhibit the enzyme. When a hydroperoxy group in liguroside A was reduced by using triphenylphosphine, the resultant compound, kudingoside B, showed a lower inhibitory effect on the enzyme. These results strongly suggest the involvement of the hydroperoxy group in the irreversible inhibition of the catalytic activity of leukocyte-type 12-lipoxygenase by the monoterpene glycosides contained in the Qing Shan Lu Shui tea.


Asunto(s)
Leucocitos/efectos de los fármacos , Leucocitos/enzimología , Inhibidores de la Lipooxigenasa/química , Inhibidores de la Lipooxigenasa/farmacología , Extractos Vegetales/química , Extractos Vegetales/farmacología , Té/química , Araquidonato 12-Lipooxigenasa/química , Relación Dosis-Respuesta a Droga , Glicósidos/química , Glicósidos/farmacología , Espectroscopía de Resonancia Magnética , Estructura Molecular , Monoterpenos/química , Monoterpenos/farmacología
3.
Food Chem ; 186: 2-5, 2015 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-25976783

RESUMEN

Oxidation of low-density lipoprotein (LDL) is one of the crucial steps for atherosclerosis development, and an essential role of leukocyte-type 12-lipoxygenase expressed in macrophages in this process has been demonstrated. The biochemical mechanism of the oxidation of circulating LDL by leukocyte-type 12-lipoxygenase in macrophages has been proposed. The major ingredients in guava tea leaves which inhibited the catalytic activity of leukocyte-type 12-lipoxygenase were quercetin and ethyl gallate. Administration of extracts from guava tea leaves to apoE-deficient mice significantly attenuated atherogenic lesions in the aorta and aortic sinus. We recently showed that Qing Shan Lu Shui inhibited the catalytic activity of leukocyte-type 12-lipoxygenase. The major components inhibiting the enzyme contained in Qing Shan Lu Shui were identified to be novel monoterpene glycosides. The anti-atherogenic effect of the tea leaves might be attributed to the inhibition of leukocyte-type 12-lipoxygenase by these components.


Asunto(s)
Aterosclerosis/prevención & control , Leucocitos/enzimología , Inhibidores de la Lipooxigenasa/química , Extractos Vegetales/química , Psidium/química , Animales , Aorta/metabolismo , Apolipoproteínas E/genética , Araquidonato 12-Lipooxigenasa/metabolismo , Relación Dosis-Respuesta a Droga , Ácido Gálico/análogos & derivados , Ácido Gálico/química , Glicósidos/química , Concentración 50 Inhibidora , Lipoproteínas LDL/metabolismo , Macrófagos/enzimología , Ratones , Ratones Noqueados , Monoterpenos/química , Oxidación-Reducción , Hojas de la Planta/química , Quercetina/química
4.
Molecules ; 18(4): 4257-66, 2013 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-23579993

RESUMEN

We evaluated the inhibitory effect of 12 Chinese teas on leukocyte-type 12-lipoxygenase (LOX) activity. Tea catechins such as epigallocatechin gallate have been known to exhibit leukocyte-type 12-LOX inhibition. Qing Shan Lu Shui, which contains lower catechin levels than the other tested teas, suppressed leukocyte-type 12-LOX activity. To characterize the bioactive components of Qing Shan Lu Shui, leukocyte-type 12-LOX inhibitory activity-guided fractionation of the aqueous ethanol extract of the tea was performed, resulting in the isolation of two new monoterpene glycosides: liguroside A (1) and B (2). The structures of compounds 1 and 2 were characterized as (2E,5E)-7-hydroperoxy-3,7-dimethyl-2,5-octadienyl-O-(α-L-rhamnopyranosyl)-(1″→3')-(4'″-O-trans-p-coumaroyl)-ß-D-glucopyranoside and (2E,5E)-7-hydroperoxy-3,7-dimethyl-2,5-octa-dienyl- O-(α-L-rhamnopyranosyl)-(1″→3')-(4'″-O-cis-p-coumaroyl)-ß-D-glucopyranoside, respectively, based on spectral and chemical evidence. Ligurosides A (1) and B (2) showed inhibitory effects on leukocyte-type 12-LOX activity, with IC50 values of 1.7 and 0.7 µM, respectively.


Asunto(s)
Glicósidos/farmacología , Leucocitos/efectos de los fármacos , Inhibidores de la Lipooxigenasa/farmacología , Monoterpenos/farmacología , Té/química , Animales , Araquidonato 12-Lipooxigenasa/metabolismo , Catequina/análogos & derivados , Catequina/farmacología , Glicósidos/química , Inhibidores de la Lipooxigenasa/química , Monoterpenos/química , Porcinos
5.
Biochem Biophys Res Commun ; 392(3): 421-5, 2010 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-20079714

RESUMEN

Leukotriene C(4) (LTC(4)) is synthesized by binding of glutathione to LTA(4), an epoxide derived from arachidonic acid, and further metabolized to LTD(4) and LTE(4). We previously prepared a monoclonal antibody with a high affinity and specificity to LTC(4). To explore the structure of the antigen-binding site of a monoclonal antibody against LTC(4) (mAbLTC), we isolated full-length cDNAs for heavy and light chains of mAbLTC. The heavy and light chains consisted of 461 and 238 amino acids including a signal peptide with molecular weights of 51,089 and 26,340, respectively. An expression plasmid encoding a single-chain antibody comprising variable regions of mAbLTC heavy and light chains (scFvLTC) was constructed and expressed in COS-7 cells. The recombinant scFvLTC showed a high affinity with LTC(4) comparable to mAbLTC. The scFvLTC also bound to LTD(4) and LTE(4) with 48% and 17% reactivities, respectively, as compared with LTC(4) binding, whereas the antibody showed almost no affinity for LTB(4).


Asunto(s)
Anticuerpos Monoclonales/biosíntesis , Cadenas Ligeras de Inmunoglobulina/biosíntesis , Leucotrieno C4/inmunología , Secuencia de Aminoácidos , Animales , Anticuerpos Monoclonales/genética , Clonación Molecular , ADN Complementario/genética , Cadenas Ligeras de Inmunoglobulina/genética , Ratones , Datos de Secuencia Molecular , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/genética
6.
Artículo en Inglés | MEDLINE | ID: mdl-19457650

RESUMEN

Prostaglandin endoperoxide H synthase (PGHS) is a key enzyme for the synthesis of prostaglandins (PGs) which play important roles in inflammation and carcinogenesis. Because the extract from Psidium guajava is known to have a variety of beneficial effects on our body including the anti-inflammatory, antioxidative and antiproliferative activities, we investigated whether the extract inhibited the catalytic activity of the two PGHS isoforms using linoleic acid as an alternative substrate. The guava leaf extract inhibited the cyclooxygenase reaction of recombinant human PGHS-1 and PGHS-2 as assessed by conversion of linoleic acid to 9- and 13-hydroxyoctadecadienoic acids (HODEs). The guava leaf extract also inhibited the PG hydroperoxidase activity of PGHS-1, which was not affected by nonsteroidal anti-inflammatory drugs (NSAIDs). Quercetin which was one of the major components not only inhibited the cyclooxygenase activity of both isoforms but also partially inhibited the PG hydroperoxidase activity. Overexpression of human PGHS-1 and PGHS-2 in the human colon carcinoma cells increased the DNA synthesis rate as compared with mock-transfected cells which did not express any isoforms. The guava leaf extract not only inhibited the PGE(2) synthesis but also suppressed the DNA synthesis rate in the PGHS-1- and PGHS-2-expressing cells to the same level as mock-transfected cells. These results demonstrate the antiproliferative activity of the guava leaf extract which is at least in part caused by inhibition of the catalytic activity of PGHS isoforms.


Asunto(s)
Antineoplásicos/farmacología , Proliferación Celular/efectos de los fármacos , Ciclooxigenasa 1/metabolismo , Ciclooxigenasa 2/metabolismo , Inhibidores de la Ciclooxigenasa/farmacología , Hojas de la Planta/química , Línea Celular Tumoral , Ciclooxigenasa 1/genética , Ciclooxigenasa 2/genética , Humanos , Isoenzimas/genética , Isoenzimas/metabolismo , Ácido Linoleico/metabolismo , Ácidos Linoleicos/metabolismo , Ácidos Linoleicos Conjugados/metabolismo , Extractos Vegetales/farmacología , Psidium , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
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