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1.
Climacteric ; 24(6): 560-571, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-33759670

RESUMEN

Vulvovaginal pathology impairs the quality of life of both women in menopause and those who are not. Different therapies have been proposed, mainly related to estrogen therapy in postmenopausal women. However, some contraindications limit its use, and different moisturizers or lubricants have been tested. Hyaluronic acid is a promising and widely used vaginal medical treatment with a moisturizing action and appears to provide a solution. For this reason, we performed a systematic review of the literature. We searched for original articles without date restriction until 30 April 2020. We included all clinical trials which administered local hyaluronic acid in the vulva or vagina. Only English studies and those performed in humans were eligible. Seventeen original studies were included in the review (from randomized controlled trials to longitudinal studies). Hyaluronic acid was generally found to be effective in improving vulvovaginal symptoms (dyspareunia, itching, burning, dryness) and signs (bleeding, atrophy, vaginal pH). In conclusion, hyaluronic acid has the properties to be an efficient moisturizer for women suffering from vulvovaginal atrophy who have contraindications for estrogen therapy and for vulvovaginal signs and symptoms affecting sexual well-being. However, a well-designed randomized controlled trial is needed in order to clarify its efficacy and safety profile.


Asunto(s)
Ácido Hialurónico/uso terapéutico , Calidad de Vida , Administración Intravaginal , Atrofia , Estrógenos , Femenino , Humanos , Vulva
2.
Gynecol Endocrinol ; 35(10): 894-898, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31081709

RESUMEN

Several studies have compared the effectiveness of corifollitropin alfa versus daily gonadotropins in poor ovarian responders (PORs) undergoing controlled ovarian stimulation (COS), showing conflicting results in terms of IVF outcomes. Given the heterogeneity of patients included in the classification of POR according to 'Bologna criteria', the aim of this study was to evaluate the impact of corifollitropin alfa in two different categories of POR distinguished according to patients' antral follicle count (AFC). We retrospectively evaluated 104 infertile POR, split into two groups according to AFC (Group A ≤ 5; Group B > 5) and subgroups according to the ovarian stimulation regimen (corifollitropin alfa plus daily gonadotropins (Subgroup 1) versus daily gonadotropins alone (Subgroup 2)). Outcome measures were total oocytes, MII oocytes, total embryos, follicular output rate (FORT), implantation rate (IR), clinical pregnancy rate (CPR), miscarriage rate (MR), and live birth rate (LBR). Subgroup A1 experienced a lower number of total oocytes, MII oocytes, total embryos, and FORT (p < .05) in comparison to Subgroup A2, while no difference was found when comparing Subgroups B1 and B2. No difference was found between subgroups even in terms of IR, CPR, MR, and LBR. In conclusion, corifollitropin alfa may be as effective as daily gonadotropins in POR with AFC > 5 undergoing COS, while it might be inferior to daily gonadotropins in POR with AFC ≤ 5.


Asunto(s)
Tasa de Natalidad , Hormona Folículo Estimulante Humana/administración & dosificación , Inducción de la Ovulación/métodos , Índice de Embarazo , Adulto , Femenino , Fertilización In Vitro/métodos , Humanos , Persona de Mediana Edad , Embarazo , Estudios Retrospectivos , Resultado del Tratamiento
3.
Gynecol Endocrinol ; 34(9): 752-755, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29463152

RESUMEN

The influence of thyroid autoimmunity in assisted reproductive technology (ART) outcome in euthyroid women is still controversial. In this study, we retrospectively evaluated embryo quality in 123 euthyroid women undergoing ART with or without thyroid autoantibodies (TAA). Embryo quality was assessed in 119 embryos of 29 infertile patients with TAA and in 394 embryos of 94 infertile patients without TAA. Our results showed not statistically significant differences in age, body mass index, anti-Müllerian hormone, follicle stimulating hormone, free triiodothyronine, and free thyroxine levels between cases and controls. Thyroid stimulating hormone was within the normal range, but significantly higher in TAA patients compared with the controls (2.4 ± 0.8 vs. 2 ± 0.9 mIU/L, respectively, p < .01). The number of oocytes picked up and fertilized was comparable between the two groups. Embryo quality was significantly impaired in women with at least one autoantibody (p < .001). Implantation rate, pregnancy rate, and ongoing pregnancy rate were comparable in the two groups. These results suggest a negative impact of thyroid autoimmunity in embryo quality in women undergoing ART even when thyroid function is normal.


Asunto(s)
Autoanticuerpos/sangre , Autoinmunidad/fisiología , Implantación del Embrión/fisiología , Infertilidad Femenina/terapia , Técnicas Reproductivas Asistidas , Glándula Tiroides/inmunología , Factores de Edad , Hormona Antimülleriana/sangre , Femenino , Hormona Folículo Estimulante/sangre , Humanos , Infertilidad Femenina/sangre , Infertilidad Femenina/inmunología , Embarazo , Índice de Embarazo , Estudios Retrospectivos , Tiroxina/sangre , Triyodotironina/sangre
4.
J Endocrinol Invest ; 39(9): 1015-21, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27072668

RESUMEN

PURPOSE: Spironolactone (SP) is an effective treatment for polycystic ovary syndrome (PCOS), but it is often associated with menstrual abnormalities whose mechanism is still under investigation. In this study, we investigated the serum sex steroids and endometrial thickness in 30 PCOS patients, before and after one-month 100 mg SP treatment. METHODS: Serum FSH, LH, estradiol, progesterone and endometrial thickness were evaluated at the 14th and 16th day of the menstrual cycle, before and during short-term SP treatment. According to the presence (15 cases) or absence (15 cases) of menstrual bleeding at the 14th day during SP, the patients were divided into two groups, which were then compared using a two-tailed Student's t test. RESULTS: Serum estradiol and endometrial thickness were lower than pretreatment at both determinations in all patients, but patients with bleeding had significantly lower estradiol values than non-bleeding ones, both before and after therapy. Endometrial thickness was significantly lower in the bleeding group compared with non-bleeding group only at the 16th day of the cycle. These differences were significant, even though the values of estradiol and endometrial thickness remained in the normal range. CONCLUSIONS: SP therapy can reduce the values of estradiol and the endometrial thickness in patients with PCOS compared with pretreatment, but PCOS patients with bleeding had pretreatment estradiol values lower than the patients who did not complain of this side effect. Intermenstrual abnormalities may represent the low estrogen impregnation of endometrium due to SP, whose mechanism is complex, involving several factors, such as the effects of some metabolites of SP on estradiol and progesterone production, on their receptors, and the individual metabolism of SP in vivo.


Asunto(s)
Índice de Masa Corporal , Ciclo Menstrual/efectos de los fármacos , Metrorragia/inducido químicamente , Antagonistas de Receptores de Mineralocorticoides/efectos adversos , Síndrome del Ovario Poliquístico/tratamiento farmacológico , Espironolactona/efectos adversos , Adulto , Femenino , Humanos , Ultrasonografía , Adulto Joven
5.
Int J Androl ; 34(5 Pt 1): 411-9, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20738429

RESUMEN

Generation of controlled amounts of reactive oxygen species (ROS) and phosphorylation of protein tyrosine (Tyr) residues are two main cellular changes involved in sperm capacitation. This study examined the relationship between tyrosine-phosphorylation (Tyr-P) and endogenous ROS production during sperm capacitation, and correlated them with both sperm motility and functionality expressed as acrosome-reacted cells. Immediate ROS generation was observed to peak after a 45-min incubation, followed by a rapid decrease in ROS content and successive regeneration of the ROS peak in 3 h and later. These two peaks were directly correlated with both the Tyr-P process involving sperm heads and tails, and the acrosome reaction (69 ± 8% and 65 ± 4%, respectively). The period of low-ROS content resulted in low Tyr-P patterns, located exclusively in the cell midpiece, and drastic reduction in acrosome-reacted cells. Ascorbic acid addition inhibited both Tyr-P patterns and acrosome reactions, whereas NADPH induced high ROS generation, with Tyr-P patterns located only on sperm tails, and prevented the acrosome reaction. Sperm hyperactivation was insensitive to ROS content. This is an important parameter for evaluation of sperm capacitation, which is achieved only when both ROS generation reaches a peak and Tyr-P involves the sperm head.


Asunto(s)
Especies Reactivas de Oxígeno/metabolismo , Capacitación Espermática , Tirosina/metabolismo , Adulto , Western Blotting , Humanos , Inmunohistoquímica , Luminiscencia , Masculino , NADP/metabolismo , Fosforilación
6.
Biochim Biophys Acta ; 1148(1): 157-60, 1993 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-8388726

RESUMEN

In human erythrocytes, okadaic acid, a potent inhibitor of certain protein phosphatases, promotes a marked increase of Ser/Thr-phosphorylation of membrane proteins, including band-3 protein. Moreover, okadaic acid also increases the band-3-mediated oxalate transport across the membranes, thus suggesting that this process is regulated by Ser/Thr-phosphorylation of transporter band-3 protein.


Asunto(s)
Proteína 1 de Intercambio de Anión de Eritrocito/metabolismo , Proteína 1 de Intercambio de Anión de Eritrocito/fisiología , Eritrocitos/efectos de los fármacos , Serina/metabolismo , Treonina/metabolismo , Transporte Biológico/efectos de los fármacos , Éteres Cíclicos/farmacología , Humanos , Ácido Ocadaico , Oxalatos/farmacocinética , Fosfoproteínas Fosfatasas/antagonistas & inhibidores , Fosforilación
7.
Biochim Biophys Acta ; 1199(3): 266-70, 1994 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-7718030

RESUMEN

Spermine, ubiquitous intracellular polyamine, is able to promote the transmembrane translocation of casein kinase CKII through the outer membrane of rat liver mitochondria and its binding to more internal mitochondrial structures. These findings suggest that spermine may play a critical role in regulating the subcellular distribution of casein kinase CKII.


Asunto(s)
Mitocondrias Hepáticas/enzimología , Proteínas Serina-Treonina Quinasas/metabolismo , Espermina/fisiología , Animales , Quinasa de la Caseína II , Membranas Intracelulares/metabolismo , Proteínas Serina-Treonina Quinasas/aislamiento & purificación , Ratas
8.
J Hum Hypertens ; 13(5): 321-7, 1999 May.
Artículo en Inglés | MEDLINE | ID: mdl-10376850

RESUMEN

The kinetic properties of sodium-proton exchange are abnormal in human red blood cells of hypertensive patients and it has been demonstrated that the transport protein undergoes post-translational modifications able to affect its kinetic properties. Protein kinase C (PKC) activation decreases the affinity constant for intracellular protons while insulin increases the maximal rate of proton translocation. The present study therefore aimed to examine the relationships among PKC activity, fasting insulin levels and the kinetic behaviour of sodium-proton exchange in red blood cells from 20 normotensives and 36 hypertensives. In comparison with normotensive subjects, hypertensive patients had higher body mass index (26.2 +/- 0.7 vs 23.6 +/- 0.6 kg/m2, P < 0.05), higher fasting insulin levels (93.2 +/- 10.8 vs 38.6 +/- 2.9 pmol/L), increased maximal velocity of proton translocation (37.9 +/- 2.7 vs 27.6 +/- 1.9 mmol/L per cell x h, P < 0.05), and reduced Hill's coefficient (1.6 +/- 0.1 vs 2.0 +/- 0.1, P < 0.01) of sodium-proton exchange. Basal PKC activity of the cytosol and membrane was similar in the study groups. However, after treatment with 1 micromol/L phorbol 12-myristate 13-acetate (PMA) for 10 min, membrane PKC activity was stimulated to a larger extent in hypertensives (to 181 +/- 8 pmol/min/mg protein) than in normotensives (to 136 +/- 6 pmol/min/mg protein, P < 0.01). The PMA stimulated PKC activity was positively correlated to fasting insulin levels (r = 0.59, P < 0.01). Stimulation of membrane PKC by PMA corrected the low Hill's coefficient for H(i)+ activation of sodium-proton exchange in the hypertensives, while the constant for half maximal activation for intracellular protons (ie, the affinity for intracellular protons) decreased to a similar extent in both groups. The maximal transport rate was unaffected by PMA. These results indicate that the abnormal proton activation of red blood cell sodium-proton exchange in hypertensives reflects an abnormal regulation of PKC translocation to the cell membrane, associated to hyperinsulinaemia and probably insulin resistance. Therefore, post-translational modifications of the transport protein(s) account for the altered kinetic behaviour of sodium-proton exchange in hypertensives.


Asunto(s)
Eritrocitos/metabolismo , Hipertensión/metabolismo , Insulina/metabolismo , Proteína Quinasa C/metabolismo , Intercambiadores de Sodio-Hidrógeno/metabolismo , Adulto , Análisis de Varianza , Femenino , Humanos , Cinética , Masculino , Persona de Mediana Edad
9.
Am J Clin Oncol ; 8(6): 528-32, 1985 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-4083271

RESUMEN

Levonantradol is a synthetic cannabinoid with demonstrated preclinical antiemetic activity. The current phase I trial was undertaken to determine: 1) the maximally tolerated dose; 2) the side effects at the different dosage levels; and 3) to evaluate the antiemetic efficacy of levonantradol in patients receiving emesis-producing chemotherapy. Thirty-four patients received 52 courses of levonantradol. Concurrent chemotherapy most frequently consisted of high dose cisplatin (120 mg/m2), either alone or in combination with other agents. Levonantradol dosage was escalated through seven treatment levels (0.5-4.0 mg per dose) and was given intramuscularly every 4 hours. Toxicity was similar to that observed with other cannabinoids and primarily consisted of dizziness (65%), burning and erythema at the injection site (48%), mild sedation (44%), orthostatic hypotension (37%), dysphoria (29%), and urinary retention (10%). Marked urinary retention occurred in three of seven patients at the 4.0 mg per dose level, and two of 24 patients at either the 2.5 mg and 3.0 mg levels. Major or minor antiemetic responses (0-2 or 3-5 emetic episodes, respectively) occurred in 23% of patients receiving cisplatin and in 53% of patients receiving non-cisplatin containing chemotherapy. Intramuscular levonantradol can be given safely at doses up to 3.0 mg/kg, with toxicity and antiemetic efficacy similar to that observed with other cannabinoids.


Asunto(s)
Antieméticos/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Fenantridinas/efectos adversos , Adulto , Anciano , Antieméticos/administración & dosificación , Cisplatino/administración & dosificación , Ciclofosfamida/administración & dosificación , Dactinomicina/administración & dosificación , Relación Dosis-Respuesta a Droga , Evaluación de Medicamentos , Femenino , Humanos , Inyecciones Intramusculares , Masculino , Persona de Mediana Edad , Fenantridinas/administración & dosificación
10.
Biochem Int ; 26(6): 1065-72, 1992 May.
Artículo en Inglés | MEDLINE | ID: mdl-1632802

RESUMEN

Band 3, the major transmembrane multifunctional protein of human erythrocytes, has been found to be phosphorylated-dephosphorylated on both Ser/Thr- and Tyr-residues by specific protein kinases and protein phosphatases. The results reported here would indicate that the ghosts prepared from human erythrocytes pretreated with DIDS, well known inhibitor of band 3-mediated anion transport, exhibit a markedly reduced Ser/Thr-phosphorylation of spectrin and band 3, when incubated with [gamma-32P]ATP in the presence of Mg2+. On the other hand, Tyr-phosphorylation of this latter protein is practically unchanged or even slightly enhanced. This suggests that Ser/Thr- and Tyr-phosphorylation of band 3 display a different functional role.


Asunto(s)
Ácido 4-Acetamido-4'-isotiocianatostilbeno-2,2'-disulfónico/análogos & derivados , Membrana Eritrocítica/efectos de los fármacos , Proteínas de la Membrana/efectos de los fármacos , Ácido 4,4'-Diisotiocianostilbeno-2,2'-Disulfónico , Ácido 4-Acetamido-4'-isotiocianatostilbeno-2,2'-disulfónico/farmacología , Proteína 1 de Intercambio de Anión de Eritrocito/química , Proteína 1 de Intercambio de Anión de Eritrocito/efectos de los fármacos , Proteína 1 de Intercambio de Anión de Eritrocito/metabolismo , Sitios de Unión , Membrana Eritrocítica/metabolismo , Humanos , Técnicas In Vitro , Proteínas de la Membrana/sangre , Proteínas de la Membrana/química , Fosforilación , Serina/química , Espectrina/química , Espectrina/efectos de los fármacos , Espectrina/metabolismo , Treonina/química , Tirosina/química
11.
Biochem Biophys Res Commun ; 178(3): 1021-7, 1991 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-1651709

RESUMEN

The pH-dependence of the distribution of Tyr- and Ser/Thr-protein kinases between cytosol and membrane in human erythrocytes was investigated. When the internal pH of human erythrocytes is decreased from 8 to 7.3 the membrane-associated Tyr-protein kinase activity markedly increases at expense of the cytosolic counterpart, whereas the membrane-bound and cytosolic casein kinase activity are unaffected. This different response of the two kinase activities to the imposed variation of intracellular pH may explain why the Tyr-phosphorylation of cytoplasmic domain of band 3 results to be much higher in the ghosts from erythrocytes whose internal pH was 7.3 than that in the ghosts from erythrocytes whose internal pH was 8. By contrast, the Ser-phosphorylation of spectrin beta-subunit (band 2) and band 3 results to be practically unchanged in the ghosts from the erythrocytes treated at both pH values.


Asunto(s)
Eritrocitos/enzimología , Proteínas de la Membrana/sangre , Proteínas Quinasas/sangre , Proteínas Tirosina Quinasas/sangre , Proteínas Quinasas Dependientes de Calcio-Calmodulina , Citosol/enzimología , Membrana Eritrocítica/metabolismo , Humanos , Concentración de Iones de Hidrógeno , Técnicas In Vitro , Cinética , Proteínas de la Membrana/aislamiento & purificación , Fosfoproteínas/sangre , Fosfoproteínas/aislamiento & purificación , Fosforilación
12.
Eur J Biochem ; 240(2): 394-9, 1996 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-8841404

RESUMEN

Band-3 protein (approximately 95 kDa), the major and multifunctional transmembrane protein of human erythrocytes, has been shown to be phosphorylated by endogenous Tyr-protein kinases on different Tyr residues at its N and C cytoplasmic domains. Both the added p36syk (catalytic domain of p72syk) and Lyn kinases are able to phosphorylate the isolated cytoplasmic domain of band 3 (cdb3), yielded by chymotryptic digestion of band 3 in the isolated membranes (ghosts). However, the two Tyr-protein kinases exhibited different phosphorylation behaviours when added to the isolated erythrocyte membranes. More precisely, the added p36syk markedly Tyr phosphorylates the band-3 protein, whereas the added Lyn phosphorylates it very poorly. It is of interest that Lyn can associate with membranes and markedly phosphorylate band 3 when this latter protein has been previously phosphorylated by p36syk, i.e. the p36(syk)-catalyzed phosphorylation is proposed to be a prerequisite for the association of Lyn with the membrane (likely to band 3) and for the Lyn-catalyzed phosphorylation of different band-3 Tyr sites.


Asunto(s)
Proteína 1 de Intercambio de Anión de Eritrocito/metabolismo , Membrana Eritrocítica/metabolismo , Tirosina/metabolismo , Familia-src Quinasas/metabolismo , Adenosina Trifosfato/metabolismo , Secuencia de Aminoácidos , Proteína 1 de Intercambio de Anión de Eritrocito/química , Western Blotting , Cromatografía en Agarosa , Cromatografía en Capa Delgada , Electroforesis en Gel de Poliacrilamida , Precursores Enzimáticos/metabolismo , Membrana Eritrocítica/química , Humanos , Péptidos y Proteínas de Señalización Intracelular , Cinética , Proteínas de la Membrana/metabolismo , Datos de Secuencia Molecular , Mapeo Peptídico , Fosforilación , Unión Proteica , Proteínas Tirosina Quinasas/metabolismo , Quinasa Syk
13.
Biochem Biophys Res Commun ; 187(2): 853-8, 1992 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-1382423

RESUMEN

In human erythrocytes Ser/Thr- and Tyr-phosphorylations of cytoplasmic domain of band 3 are catalyzed by casein kinase I and Tyr-protein kinase respectively, both distributed between cytosol and membrane structures. The results reported here show that purified cytosolic Tyr-protein kinase activity, assayed on added substrates such as poly(Glu,Tyr)4:1 and isolated chymotryptic fragments of band 3 cytoplasmic domain (cdb3), is potently inhibited by PIP and even more by PIP2. Similar inhibitory effects are displayed by these polyphosphoinositides also on the endogenous Tyr-phosphorylation of band 3, when they are added to the isolated native membranes, thus suggesting their involvement in regulating in-vivo Tyr-phosphorylation of membrane proteins.


Asunto(s)
Eritrocitos/enzimología , Fosfatos de Fosfatidilinositol , Fosfatidilinositoles/farmacología , Proteínas Tirosina Quinasas/antagonistas & inhibidores , Adenosina Trifosfato/metabolismo , Proteína 1 de Intercambio de Anión de Eritrocito/metabolismo , Quimotripsina/metabolismo , Humanos , Concentración de Iones de Hidrógeno , Fragmentos de Péptidos/sangre , Fosfatidilinositol 4,5-Difosfato , Fosfoserina/metabolismo , Fosfotirosina , Proteínas Tirosina Quinasas/sangre , Tirosina/análogos & derivados , Tirosina/sangre
14.
Biochem Biophys Res Commun ; 195(2): 723-9, 1993 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-8396924

RESUMEN

Okadaic acid, penetrating the human erythrocytes, almost completely inhibits P-Ser-protein phosphatase activity, whereas it unaffects Ser/Thr-protein kinase activity (casein kinases CKI and CKII), thus promoting a marked increase of the endogenous Ser-phosphorylation level of membrane proteins, such as cytoskeletal spectrin beta-subunit (band 2) and transmembrane band 3 protein. By contrast, the Tyr-phosphorylation state of band 3 protein is practically unaffected by okadaic acid, being unaffected both Tyr-protein kinase and P-Tyr-protein phosphatase activities.


Asunto(s)
Membrana Eritrocítica/metabolismo , Éteres Cíclicos/farmacología , Proteínas de la Membrana/sangre , Caseína Quinasas , Citosol/enzimología , Membrana Eritrocítica/efectos de los fármacos , Eritrocitos/enzimología , Humanos , Cinética , Ácido Ocadaico , Fosfoproteínas Fosfatasas/antagonistas & inhibidores , Fosfoproteínas Fosfatasas/sangre , Fosforilación , Proteínas Quinasas/sangre
15.
Miner Electrolyte Metab ; 19(1): 17-20, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8393959

RESUMEN

This study was carried out to verify the hypothesis of a link between faster endogenous phosphorylation of band 3 protein, the anion carrier, and anomalous oxalate transmembrane self-exchange found in erythrocyte from calcium oxalate renal stone formers. Agents able to modify 32P-labelling of band 3 protein induced a concurrent modification in oxalate transmembrane flux. Cyclic AMP- and phospholipid-sensitive Ca(2+)-independent protein kinases seem to be critical modulators of band 3 function. These observations demonstrate a close link between the band 3 phosphorylation state and its anion transport function, and provide new insights into the pathogenetic mechanisms of the cellular anomalies observed in calcium-oxalate renal stone disease.


Asunto(s)
Proteína 1 de Intercambio de Anión de Eritrocito/metabolismo , Aniones , Oxalato de Calcio/análisis , Membrana Eritrocítica/metabolismo , Cálculos Renales/sangre , Oxalatos/sangre , Transporte Biológico , AMP Cíclico/sangre , Humanos , Cálculos Renales/química , Ácido Oxálico , Radioisótopos de Fósforo , Fosforilación
16.
Biochem Biophys Res Commun ; 205(1): 389-95, 1994 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-7999054

RESUMEN

The results indicated here, together with those previously reported, show that spermine, ubiquitous polyamine, while promoting the transmembrane translocation of casein kinase II (CKII) across the outer membrane to more internal compartments of rat liver mitochondria, promotes the binding of casein kinase I (CKI) to the external surface of outer mitochondrial membrane but inhibits its spontaneously occurring binding to more internal structures.


Asunto(s)
Mitocondrias Hepáticas/efectos de los fármacos , Proteínas Quinasas/metabolismo , Espermina/farmacología , Animales , Caseína Quinasas , Membranas Intracelulares/efectos de los fármacos , Membranas Intracelulares/enzimología , Mitocondrias Hepáticas/enzimología , Ratas , Especificidad por Sustrato
17.
Biochem Biophys Res Commun ; 203(1): 681-5, 1994 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-8074722

RESUMEN

The present paper shows that an increased phosphorylation of the membrane proteins, promoted by the okadaic acid (strong inhibitor of P-Ser/Thr-protein phosphatase(s)), is accompanied by a release of casein kinase from the membrane into cytosol. Such an intracellular translocation might provide a feedback mechanism for the regulation of the casein kinase catalyzed phosphorylation of membrane proteins in the human erythrocytes.


Asunto(s)
Membrana Eritrocítica/metabolismo , Eritrocitos/enzimología , Proteínas de la Membrana/sangre , Fosfoproteínas/sangre , Proteínas Quinasas/sangre , Adenosina Trifosfato/metabolismo , Caseína Quinasas , Citosol/enzimología , Electroforesis en Gel de Poliacrilamida , Humanos , Técnicas In Vitro , Cinética , Proteínas de la Membrana/aislamiento & purificación , Fosfoproteínas/aislamiento & purificación , Radioisótopos de Fósforo , Fosforilación
18.
Biochem Biophys Res Commun ; 213(1): 249-57, 1995 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-7543753

RESUMEN

The Tyr-phosphorylation of the cytoplasmic domain of the major membrane-spanning band 3, rather than the Ser/Thr-phosphorylation of the membrane proteins (spectrin and band 3 itself), might be functionally related to certain morphological changes of human erythrocytes. This view is supported by the following lines of evidence: a) vanadate or its derivative pervanadate (vanadyl hydroperoxide), which markedly increase the Tyr-phosphorylation of band 3 (without practically affecting the Ser/Thr-phosphorylation of spectrin) promotes a crenation of human erythrocytes; b) okadaic acid, which selectively increases the Ser/Thr-phosphorylation of spectrin and other membrane proteins, does not promote any shape change, at least at a level detectable with scanning electron microscopy.


Asunto(s)
Membrana Eritrocítica/metabolismo , Membrana Eritrocítica/ultraestructura , Proteínas de la Membrana/sangre , Proteína 1 de Intercambio de Anión de Eritrocito/aislamiento & purificación , Proteína 1 de Intercambio de Anión de Eritrocito/metabolismo , Membrana Eritrocítica/efectos de los fármacos , Éteres Cíclicos/farmacología , Humanos , Proteínas de la Membrana/efectos de los fármacos , Proteínas de la Membrana/aislamiento & purificación , Microscopía Electrónica de Rastreo , Ácido Ocadaico , Fosfoproteínas Fosfatasas/antagonistas & inhibidores , Fosfoproteínas/efectos de los fármacos , Fosfoproteínas/aislamiento & purificación , Fosfoproteínas/metabolismo , Fosforilación , Fosfotirosina , Espectrina/aislamiento & purificación , Espectrina/metabolismo , Tirosina/análogos & derivados , Tirosina/análisis , Tirosina/metabolismo , Vanadatos/farmacología
19.
J Am Soc Nephrol ; 10 Suppl 14: S381-4, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10541268

RESUMEN

Greater arachidonic acid (AA) contents, which were correlated with erythrocyte transmembrane oxalate (Ox) transport, were observed in plasma and erythrocyte membrane phospholipids of patients with idiopathic calcium renal stones, suggesting a link between membrane phospholipid fatty acid composition and cellular Ox transport. To confirm this hypothesis, the effects of exogenous red blood cell incorporation of three different fatty acids (i.e., oleic acid, AA, and eicosapentaenoic acid) on Ox transport and the phosphorylation status of band 3 protein, which has been shown to mediate red blood cell Ox flux, were investigated. Preincubation of erythrocytes with AA induced a dose-dependent increase in the phosphorylation level of band 3 protein and an increase in transmembrane Ox self-exchange. In contrast, inhibitory effects on both parameters were observed after the incorporation of oleic and eicosapentaenoic acids. These data, together with previous observations of dietary effects on erythrocyte Ox transport and urinary Ox excretion, indicate that genetic and/or nutritional changes in membrane phospholipid fatty acid composition play a crucial role in modulating cellular Ox transport in idiopathic calcium Ox nephrolithiasis.


Asunto(s)
Ácido Araquidónico/farmacología , Oxalato de Calcio/metabolismo , Eritrocitos/metabolismo , Cálculos Renales/etiología , Oxalatos/metabolismo , Adulto , Transporte Biológico/efectos de los fármacos , Humanos
20.
Clin Sci (Lond) ; 102(4): 403-9, 2002 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11914102

RESUMEN

Epidemiological, clinical and experimental evidence suggests that fatty acids have a modulatory effect on bone metabolism in animals and humans. To investigate this hypothesis, we evaluated the effects of three different fatty acids, arachidonic acid (AA), eicosapentaenoic acid (EPA) and oleic acid (OA), on the expression of cytokines involved in bone remodelling. Cytokine mRNAs in the human osteoblast-like cell line MG-63 were quantified by reverse transcription-PCR. AA induced increased expression of interleukin-1alpha, interleukin-1beta, tumour necrosis factor-alpha and macrophage colony-stimulating factor mRNAs in a time- and dose-dependent manner. EPA and OA had no stimulatory effects, but instead caused a significant inhibition of AA-induced cytokine mRNA expression. Cell treatment with calphostin C, an inhibitor of protein kinase C (PKC), and cellular PKC down-regulation experiments independently resulted in significant inhibition of AA-induced cytokine expression, suggesting that a PKC-dependent mechanism accounts for the effects of AA on cytokine production. In conclusion, our study demonstrates specific effects of fatty acids on cytokine gene expression in human osteoblast-like cells. The clinical relevance of our findings requires further investigation.


Asunto(s)
Citocinas/biosíntesis , Ácidos Grasos Insaturados/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Osteoblastos/efectos de los fármacos , Ácido Araquidónico/farmacología , Línea Celular , Citocinas/genética , Relación Dosis-Respuesta a Droga , Ácido Eicosapentaenoico/farmacología , Humanos , Interleucina-1/biosíntesis , Factor Estimulante de Colonias de Macrófagos/biosíntesis , Ácido Oléico/farmacología , Osteoblastos/metabolismo , Reacción en Cadena de la Polimerasa/métodos , ARN Mensajero/genética , Factor de Necrosis Tumoral alfa/biosíntesis
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