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1.
Mol Reprod Dev ; 91(1): e23723, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38282316

RESUMEN

The Sodium Glucose Cotransporter Isoform 1 (Sglt-1) is a symporter that moves Na+ and glucose into the cell. While most studies have focused on the role of Sglt-1 in the small intestine and kidney, little is known about this transporter's expression and function in other tissues. We have previously shown that Sglt-1 is expressed in the mouse sperm flagellum and that its inhibition interferes with sperm metabolism and function. Here, we further investigated the importance of Sglt-1 in sperm, using a Sglt-1 knockout mouse (Sglt-1 KO). RNA, immunocytochemistry, and glucose uptake analysis confirmed the ablation of Sglt-1 in sperm. Sglt-1 KO male mice are fertile and exhibit normal sperm counts and morphology. However, Sglt-1 null sperm displayed a significant reduction in total, progressive and other parameters of sperm motility compared to wild type (WT) sperm. The reduction in motility was exacerbated when sperm were challenged to swim in media with higher viscosity. Parameters of capacitation, namely protein tyrosine phosphorylation and acrosomal reaction, were similar in Sglt-1 KO and WT sperm. However, Sglt-1 KO sperm displayed a significant decrease in hyperactivation. The impaired motility of Sglt-1 null sperm was observed in media containing glucose as the only energy substrate. Interestingly, the addition of pyruvate and lactate to the media partially recovered sperm motility of Sglt-1 KO sperm, both in the low and high viscosity media. Altogether, these results support an important role for Sglt-1 in sperm energetics and function, providing sperm with a higher capacity for glucose uptake.


Asunto(s)
Transportador 1 de Sodio-Glucosa , Motilidad Espermática , Animales , Masculino , Ratones , Glucosa/metabolismo , Ratones Noqueados , Semen/metabolismo , Transportador 1 de Sodio-Glucosa/genética , Transportador 1 de Sodio-Glucosa/metabolismo , Capacitación Espermática/fisiología , Motilidad Espermática/fisiología , Espermatozoides/metabolismo
2.
J Orthop Sci ; 29(2): 627-631, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36914484

RESUMEN

BACKGROUND: The self-administered foot evaluation questionnaire is a comprehensive measure for assessing the perception of patients regarding their foot-related problems. However, it is currently only available in English and Japanesse. Therefore, this study aimed to cross-culturally adapt the questionnaire to Spanish and assess its psychometric properties. METHODS: The methodology recommended by the International Society for Pharmaco Economics and Outcomes Research for translating and validating patient-reported outcome measures was followed for the Spanish translation. After a pilot study with 10 patients and 10 controls, an observational study was carried out between March and December 2021. The Spanish version of the questionnaire was filled by 100 patients with unilateral foot disorders, and the time spent to complete each questionnaire was recorded. Cronbach's alpha was calculated to analyze the internal consistency of the scale and Pearson's correlation coefficients for the degree of inter-subscale associations. RESULTS: The maximum correlation coefficient for the Physical Functioning, Daily Living, and Social Functioning subscales was 0.768. The inter-subscale correlation coefficients were significant (p < 0.001). Additionally, the value of Cronbach's alpha for the whole scale was 0.894 (95% confidence interval, 0.858-0.924). The values of Cronbach's alpha varied between 0.863 and 0.889 when the value of one of the five subscales was suppressed, which can be considered a measure of good internal consistency. CONCLUSION: The Spanish version of the questionnaire is valid and reliable. The method followed for its transcultural adaptation ensured its conceptual equivalence with the original questionnaire. Health practitioners can use the self-administered foot evaluation questionnaire as a complementary method to assess the interventions performed for ankle and foot disorders among native Spanish speakers; however, further research is necessary to assess its consistency for use by populations from other Spanish-speaking countries.


Asunto(s)
Comparación Transcultural , Extremidad Inferior , Humanos , Proyectos Piloto , Reproducibilidad de los Resultados , Encuestas y Cuestionarios , Psicometría/métodos
3.
Am J Physiol Renal Physiol ; 325(6): F857-F869, 2023 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-37823195

RESUMEN

Renal cyst progression in autosomal dominant polycystic kidney disease (ADPKD) is highly dependent on agents circulating in blood. We have previously shown, using different in vitro models, that one of these agents is the hormone ouabain. By binding to Na+-K+-ATPase (NKA), ouabain triggers a cascade of signal transduction events that enhance ADPKD cyst progression by stimulating cell proliferation, fluid secretion, and dedifferentiation of the renal tubular epithelial cells. Here, we determined the effects of ouabain in vivo. We show that daily administration of ouabain to Pkd1RC/RC ADPKD mice for 1-5 mo, at physiological levels, augmented kidney cyst area and number compared with saline-injected controls. Also, ouabain favored renal fibrosis; however, renal function was not significantly altered as determined by blood urea nitrogen levels. Ouabain did not have a sex preferential effect, with male and female mice being affected equally. By contrast, ouabain had no significant effect on wild-type mice. In addition, the actions of ouabain on Pkd1RC/RC mice were exacerbated when another mutation that increased the affinity of NKA for ouabain was introduced to the mice (Pkd1RC/RCNKAα1OS/OS mice). Altogether, this work highlights the role of ouabain as a procystogenic factor in the development of ADPKD in vivo, that the ouabain affinity site on NKA is critical for this effect, and that circulating ouabain is an epigenetic factor that worsens the ADPKD phenotype.NEW & NOTEWORTHY This work shows that the hormone ouabain enhances the progression of autosomal dominant polycystic kidney disease (ADPKD) in vivo. Ouabain augments the size and number of renal cysts, the kidney weight to body weight ratio, and kidney fibrosis in an ADPKD mouse model. The Na+-K+-ATPase affinity for ouabain plays a critical role in these effects. In addition, these outcomes are independent of the sex of the mice.


Asunto(s)
Quistes , Riñón Poliquístico Autosómico Dominante , Masculino , Femenino , Ratones , Animales , Riñón Poliquístico Autosómico Dominante/tratamiento farmacológico , Riñón Poliquístico Autosómico Dominante/genética , Riñón Poliquístico Autosómico Dominante/metabolismo , Ouabaína/farmacología , Adenosina Trifosfatasas , Quistes/metabolismo , Hormonas/metabolismo , Hormonas/farmacología , Riñón/metabolismo , Canales Catiónicos TRPP/genética , Canales Catiónicos TRPP/metabolismo , Modelos Animales de Enfermedad
4.
J Clin Med ; 12(13)2023 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-37445403

RESUMEN

Minimally invasive surgery (MIS) is currently used to correct hallux valgus deformities. Most studies reporting on MIS techniques to correct hallux valgus deformities included patients with postoperative complications. These reported complications, with an average rate of 23%, had significant negative effects on the clinical outcomes in this patient population. In the present study, a cohort of 63 women who underwent MIS hallux valgus correction was assessed preoperatively and at a mean follow-up of 1.0, 4.7, and 6.5 years using the American Orthopaedic Foot and Ankle Society (AOFAS) scale and the Manchester Oxford Foot Questionnaire (MOXFQ). The main criterion for inclusion in this cohort was a lack of complications during the entire follow-up period. The results showed significant improvements in both AOFAS and MOXFQ scores between the preoperative and 1-year follow-up assessments. By contrast, clinically small and nonsignificant changes were observed among postoperative follow-up values. The number of enrolled patients needs to be increased in future studies, with different surgeons and techniques included. Nevertheless, our study findings will inform patients about the outcomes they can expect over the years if no complications occur.

5.
FASEB J ; 37(4): e22835, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36856735

RESUMEN

Through its classic ATP-dependent ion-pumping function, basolateral Na/K-ATPase (NKA) generates the Na+ gradient that drives apical Na+ reabsorption in the renal proximal tubule (RPT), primarily through the Na+ /H+ exchanger (NHE3). Accordingly, activation of NKA-mediated ion transport decreases natriuresis through activation of basolateral (NKA) and apical (NHE3) Na+ reabsorption. In contrast, activation of the more recently discovered NKA signaling function triggers cellular redistribution of RPT NKA and NHE3 and decreases Na+ reabsorption. We used gene targeting to test the respective contributions of NKA signaling and ion pumping to the overall regulation of RPT Na+ reabsorption. Knockdown of RPT NKA in cells and mice increased membrane NHE3 and Na+ /HCO3 - cotransporter (NBCe1A). Urine output and absolute Na+ excretion decreased by 65%, driven by increased RPT Na+ reabsorption (as indicated by decreased lithium clearance and unchanged glomerular filtration rate), and accompanied by elevated blood pressure. This hyper reabsorptive phenotype was rescued upon crossing with RPT NHE3-/- mice, confirming the importance of NKA/NHE3 coupling. Hence, NKA signaling exerts a tonic inhibition on Na+ reabsorption by regulating key apical and basolateral Na+ transporters. This action, lifted upon NKA genetic suppression, tonically counteracts NKA's ATP-driven function of basolateral Na+ reabsorption. Strikingly, NKA signaling is not only physiologically relevant but it also appears to be functionally dominant over NKA ion pumping in the control of RPT reabsorption.


Asunto(s)
Túbulos Renales , Sodio , Animales , Ratones , Intercambiador 3 de Sodio-Hidrógeno , ATPasa Intercambiadora de Sodio-Potasio , Adenosina Trifosfato
6.
J Clin Med ; 11(19)2022 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-36233550

RESUMEN

There is some controversy regarding the use of one or two hamstring tendons for anterior cruciate ligament reconstruction (ACLR). In this study, two cohorts of 22 male patients underwent an ACLR with hamstring tendon autografts. One cohort was reconstructed through an all-inside technique with the semitendinosus tendon (ST group) and the other with the semitendinosus and gracilis tendons (ST-G group). Anterior tibial translation (ATT), Lysholm, and IKDC scores were assessed preoperatively and five years postoperation. Additionally, isometric knee muscle strength was manually measured in both groups and in another cohort of 22 uninjured control male subjects five years after the operation. There were no significant differences in ATT and Lysholm scores between the operated groups. The IKDC score was lower in the ST-G group than in the ST group­9.57 (CI 14.89−4.25) (p < 0.001). No significant differences between injured and uninjured knees were detected in hamstring to quadriceps ratio strength and quadriceps limb symmetry index of the two operated groups, but the hamstring limb symmetry index was significantly lower in the ST-G group than in the ST and control groups. This study shows that using an ST-G autograft for ACLR yielded less flexor strength and worse results in some patient-reported outcome measures (PROM) than using an ST autograft five years after the operation. The observed results let us suggest that the use of one autograft hamstring tendon for ACLR is clinically preferable to the use of two hamstring tendons.

7.
J Clin Med ; 11(13)2022 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-35806910

RESUMEN

The surgical correction of a hallux valgus (HV) deformity improves radiological parameters and clinical outcomes. However, it is not known how these improvements are related between themselves. In this retrospective study, 73 women were assessed preoperatively and 60 months after HV surgical correction. Several radiological parameters were measured: the hallux valgus angle (HVA), I−II intermetatarsal angle (IMA) and sesamoid position. The functional outcomes were assessed using the American Orthopaedic Foot and Ankle Society (AOFAS) Hallux Metatarsophalangeal-Interphalangeal (HMI) scale, and patient-reported outcomes (PROMs) were recorded with the Manchester−Oxford Foot Questionnaire (MOXFQ). A pre−post-surgery comparison of radiological and clinical values was performed, the correlation among them was studied and the differences pre−post-surgery in the radiological measurements compared with those for the clinical outcomes were studied. The results show that all the radiological parameters, functional outcomes and PROMs improved significantly from their pre-operative values to the follow-up values. Multivariate regression analysis showed a significant relationship (p < 0.001) between the differential pre−post-surgery AOFAS scoring only with two sesamoid position differential pre−post-surgery measures: position of medial sesamoid (PMS) and translation of the first metatarsal head (TMH). However, no significant association was observed between the pre−post-surgery radiological differences and the pre−post-surgery MOXFQ scoring.

8.
Front Cell Dev Biol ; 10: 911056, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35693932

RESUMEN

The Na,K-ATPase alpha 4 isoform (NKAα4) is expressed specifically in the male germ cells of the testes and is particularly abundant in mature spermatozoa. Genetic deletion of NKAα4 in mice (NKAα4 KO mice) results in complete infertility of male, but not female mice. The reduced fecundity of NKAα4 KO male mice is due to a series of defects, including a severe impairment in total and hyperactive sperm motility. In this work, we show that deletion of NKAα4 also leads to major defects in sperm metabolism and energetics. Thus, compared to wild-type sperm, sperm from NKAα4 KO mice display a significant reduction in the extracellular acidification rate (ECAR), indicative of impaired glycolytic flux. In addition, mitochondrial function is disrupted in sperm lacking NKAα4, as indicated by a reduction in the mitochondrial membrane potential and lower oxygen consumption rate (OCR). Moreover, the ratio between the oxidized and reduced forms of nicotinamide adenine dinucleotide (NAD/NADH) is increased in NKAα4 KO sperm, indicating a shift in the cellular redox state. These metabolic changes are associated with augmented reactive oxygen species (ROS) production and increased lipid peroxidation in NKAα4 KO sperm. Altogether, these findings reveal a novel link between NKAα4 activity and sperm energetics, highlighting the essential role of this ion transporter in sperm physiology.

9.
Biol Reprod ; 106(6): 1206-1217, 2022 06 13.
Artículo en Inglés | MEDLINE | ID: mdl-35420639

RESUMEN

Glucose is a key substrate for supporting sperm energy production and function. Previous studies have demonstrated that sperm glucose uptake is facilitated by several isoforms of the glucose transporters (GLUT). Here, we report that sperm also expresses the Na+-dependent sodium glucose cotransporter (SGLT). This was first suggested by our observation that genetic deletion of the testis-specific Na,K-ATPase α4, which impairs the sperm plasma membrane Na+ gradient, reduces glucose uptake and ATP production. Immunoblot analysis revealed the presence of an SGLT in sperm, with specific expression of isoform 1 (SGLT-1), but not of isoform 2 (SGLT-2). Immunocytochemistry identified SGLT-1 in the mid- and principal piece of the sperm flagellum. Inhibition of SGLT-1 with the isotype-selective inhibitor phlorizin significantly reduced glucose uptake, glycolytic activity, and ATP production in noncapacitated and capacitated sperm from wild-type mice. Phlorizin also decreased total sperm motility, as well as other parameters of sperm movement. In contrast, inhibition of SGLT-1 had no significant effect on sperm hyperactivation, protein tyrosine phosphorylation, or acrosomal reaction. Importantly, phlorizin treatment impaired the fertilizing capacity of sperm. Altogether, these results demonstrate that mouse sperm express a functional SGLT transport system that is important for supporting sperm energy production, motility, and fertility.


Asunto(s)
ATPasa Intercambiadora de Sodio-Potasio , Motilidad Espermática , Adenosina Trifosfato/metabolismo , Animales , Fertilidad , Glucosa/metabolismo , Masculino , Ratones , Florizina/metabolismo , Florizina/farmacología , Isoformas de Proteínas/metabolismo , Sodio/metabolismo , Sodio/farmacología , Transportador 1 de Sodio-Glucosa , ATPasa Intercambiadora de Sodio-Potasio/metabolismo , Motilidad Espermática/fisiología , Espermatozoides/metabolismo
10.
Artículo en Inglés | MEDLINE | ID: mdl-34948910

RESUMEN

Little attention has been paid to knee muscle strength after ACL rupture and its effect on prognostic outcomes and treatment decisions. We studied hamstrings (H) and quadriceps (Q) strength correlation with a patient-reported outcome measures score (International Knee Documentation Committee, IKDC), anterior tibial translation (ATT), and time post-injury in 194 anterior cruciate ligament deficient patients (ACLD) who required surgery after a failed rehabilitation program (non-copers). The correlation between knee muscle strength and ATT was also studied in 53 non-injured controls. ACLD patients showed decreased knee muscle strength of both the injured and non-injured limbs. The median (interquartile range) values of the H/Q ratio were 0.61 (0.52-0.81) for patients' injured side and 0.65 (0.57-0.8) for the non-injured side (p = 0.010). The median H/Q ratio for the controls was 0.52 (0.45-0.66) on both knees (p < 0.001, compared with the non-injured side of patients). The H/Q, ATT, and time post-injury were not significantly correlated with the IKDC score. ATT was significantly correlated with the H/Q of the injured and non-injured knees of patients, but not in the knees of the controls. Quadriceps strength and H/Q ratio were significantly correlated with ATT for both limbs of the patients. IKDC score correlated significantly with the quadriceps and hamstrings strengths of the injured limb but not with the H/Q ratio, ATT or time passed after injury.


Asunto(s)
Lesiones del Ligamento Cruzado Anterior , Ligamento Cruzado Anterior , Lesiones del Ligamento Cruzado Anterior/cirugía , Estudios Transversales , Humanos , Articulación de la Rodilla , Fuerza Muscular , Medición de Resultados Informados por el Paciente
12.
Rev. cir. (Impr.) ; 73(5): 625-633, oct. 2021. ilus, tab
Artículo en Español | LILACS | ID: biblio-1388870

RESUMEN

Resumen Introducción: Debido a su eficacia en el tratamiento de la obesidad mórbida, el bypass gástrico (BPG) sigue siendo una intervención realizada frecuentemente. Sin embargo, un grupo reducido de pacientes puede desarrollar complicaciones nutricionales y metabólicas que no logran controlarse con un tratamiento médico óptimo. En estos casos, puede ser necesario reestablecer la continuidad del tracto gastrointestinal por medio de la reversión del BPG (R-BPG). Objetivo: Presentar las indicaciones y resultados obtenidos en una serie de pacientes sometidos a una R-BPG. Materiales y Método: Identificación y evaluación retrospectiva de todos los pacientes sometidos a una R-BPG en nuestra institución de manera consecutiva. Se registraron las características demográficas y antropométricas de la cirugía original y al momento de la reversión. Las complicaciones se registraron de acuerdo con la clasificación de Clavien-Dindo. Resultados: Se identificaron 7 pacientes en los cuales se realizó una R-BPG. En 2 casos la reversión fue por síndrome de intestino corto, en 3 casos por hipoglicemias severas refractarias a manejo médico y en 2 casos por diarrea crónica. La mediana de edad al momento de la reversión fue de 55 años. La mediana de tiempo desde la cirugía original hasta el momento de la reversión fue de 77 meses. La mediana de estadía hospitalaria fue de 6 días. No hubo complicaciones Clavien-Dindo ≥ III. La R-BPG logró revertir en todos los casos las complicaciones nutricionales y metabólicas. Conclusión: La restauración de la continuidad del tracto gastrointestinal permite el control de las complicaciones nutricionales y metabólicas.


Introduction: Due to its efficacy in the treatment of morbid obesity, roux-en-y gastric bypass (RYGB) continues to be a frequently performed intervention. However, a small group of patients may develop nutritional and metabolic complications that cannot be controlled with optimal medical treatment. In these cases, it may be necessary to reestablish the continuity of the gastrointestinal tract by reversing the RYGB (R-RYGB). Aim: To present the indications and results obtained in a series of patients who underwent to R-RYGB. Materials and Method: Identification and retrospective evaluation of all patients who underwent consecutive R-RYGB in our institution. Demographic and anthropometric characteristics of the original surgery and at the time of the reversal were recorded. Complications were classified according to Clavien-Dindo classification. Results: Seven patients were identified in whom an R-RYGB was performed. In 2 cases the reversal was due to short bowel syndrome, in 3 cases due to severe hypoglycemia refractory to medical treatment and in 2 cases due to chronic diarrhea. The median age at the time of the reversal was 55 years. The median time from primary surgery to reversal was 77 months. The median hospital stay was 6 days. There were no Clavien-Dindo complications ≥ III. The R-RYGB was able to reverse nutritional and metabolic complications in all cases. Conclusion: Restoring the continuity of the gastrointestinal tract allows control of nutritional and metabolic complications.


Asunto(s)
Humanos , Esofagoplastia/métodos , Cirugía Bariátrica/efectos adversos , Cirugía Bariátrica/métodos , Prótesis e Implantes , Obesidad Mórbida/cirugía
13.
J Membr Biol ; 254(5-6): 549-561, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34129092

RESUMEN

Mammalian sperm express two Na,K-ATPase (NKA) isoforms, Na,K-ATPase α4 (NKAα4) and Na,K-ATPase α1 (NKAα1). While NKAα4 is critical to sperm motility, the role of NKAα1 in sperm movement remains unknown. We determined this here using a genetic and pharmacological approach, modifying the affinity of NKAα1 and NKAα4 for the inhibitor ouabain to selectively block the function of each isoform. Sperm from wild-type (WT) mice (naturally containing ouabain-resistant NKAα1 and ouabain-sensitive NKAα4) and three newly generated mouse lines, expressing both NKAα1 and NKAα4 ouabain resistant (OR), ouabain sensitive (OS), and with their ouabain affinity switched (SW) were used. All mouse lines produced normal sperm numbers and were fertile. All sperm types showed NKAα isoform expression levels and activity comparable to WT, and kinetics for ouabain inhibition confirming the expected changes in ouabain affinity for each NKA isoform. Ouabain at 1 µM, which only block ouabain-sensitive NKA, significantly inhibited total, progressive, and hyperactivated sperm motility in WT and OS, but had no significant effect on OR or SW sperm. Higher ouabain (1 mM), which inhibits both ouabain-sensitive and ouabain-resistant NKA, had little additional effect on sperm motility in all mouse lines, including the OR and SW. A similar pattern was found for the effect of ouabain on sperm intracellular sodium ([Na+]i). These results indicate that NKAα4, but not NKAα1 is the main contributor to sperm motility and that the ouabain affinity site in NKA is not an essential requirement for male fertility.


Asunto(s)
Motilidad Espermática , Animales , Fertilidad , Iones , Masculino , Ratones , Ouabaína/farmacología , Sodio , ATPasa Intercambiadora de Sodio-Potasio/genética
14.
Am J Pathol ; 191(9): 1592-1609, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34126085

RESUMEN

Male factors, including those of autoimmune origin, contribute to approximately 50% of infertility cases in humans. However, the mechanisms underlying autoimmune male infertility are poorly understood. Deficiency in autoimmune regulator (AIRE) impairs central immune tolerance because of diminished expression of self-antigens in the thymus. Humans with AIRE mutations and mice with engineered ablation of Aire develop multiorgan autoimmunity and infertility. To determine the immune targets contributing to infertility in male Aire-deficient (-/-) mice, Aire-/- or wild-type (WT) males were paired with WT females. Aire-/- males exhibited dramatically reduced mating frequency and fertility, hypogonadism, and reduced serum testosterone. Approximately 15% of mice exhibited lymphocytic infiltration into the testis, accompanied by atrophy, azoospermia, and reduced numbers of mitotically active germ cells; the remaining mice showed normal testicular morphology, sperm counts, and motility. However, spermatozoa from all Aire-/- mice were defective in their ability to fertilize WT oocytes in vitro. Lymphocytic infiltration into the epididymis, seminal vesicle, and prostate gland was evident. Aire-/- male mice generated autoreactive antibodies in an age-dependent manner against sperm, testis, epididymis, prostate gland, and seminal vesicle. Finally, expression of Aire was evident in the seminiferous epithelium in an age-dependent manner, as well as in the prostate gland. These findings suggest that Aire-dependent central tolerance plays a critical role in maintaining male fertility by stemming autoimmunity against multiple reproductive targets.


Asunto(s)
Infertilidad Masculina/inmunología , Poliendocrinopatías Autoinmunes/patología , Factores de Transcripción/metabolismo , Animales , Femenino , Infertilidad Masculina/genética , Masculino , Ratones , Ratones Noqueados , Poliendocrinopatías Autoinmunes/genética , Factores de Transcripción/genética , Proteína AIRE
15.
J Assist Reprod Genet ; 38(6): 1493-1505, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33977467

RESUMEN

PURPOSE: The aim of this study is to investigate the mechanisms by which the testis specific Na,K-ATPase ion transport system (Atp1a4) controls sperm morphology and shape. METHODS: Sperm from wild-type (WT) and Atp1a4 knockout (Atp1a4 KO) mice were analyzed morphologically, using light, transmission, and scanning electron microscopy; and functionally, applying sperm osmotic challenge and viability tests. In addition, a sperm proteomic study was performed. RESULTS: Light microscopy confirmed that sperm lacking Atp1a4 present a bend at the junction of the mid- and principal piece of the flagellum. This bend had different degrees of angulation, reaching occasionally a complete flagellar retroflexion. The defect appeared in sperm collected from the cauda epididymis, but not the epididymal caput or the testis. Transmission and scanning electron microscopy revealed a dilation of the cytoplasm at the site of the bend, with fusion of the plasma membrane in overlapping segments of the flagellum. This was accompanied by defects in the axoneme and peri-axonemal structures. Sperm from Atp1a4 KO mice showed an abnormal response to hypoosmotic challenge with decreased viability, suggesting reduced capacity for volume regulation. Exposure to Triton X-100 only partially recovered the flagellar bend of Atp1a4 KO sperm, showing that factors other than osmotic regulation contribute to the flagellar defect. Interestingly, several key sperm structural proteins were expressed in lower amounts in Atp1a4 KO sperm, with no changes in their localization. CONCLUSIONS: Altogether, our results show that Atp1a4 plays an important role in maintaining the proper shape of the sperm flagellum through both osmotic control and structurally related mechanisms.


Asunto(s)
Proteómica , ATPasa Intercambiadora de Sodio-Potasio/genética , Cola del Espermatozoide/ultraestructura , Animales , Forma de la Célula/genética , Humanos , Masculino , Ratones , Ratones Noqueados , Isoformas de Proteínas/genética , Motilidad Espermática/genética , Cola del Espermatozoide/patología , Espermatozoides/patología , Espermatozoides/ultraestructura , Testículo/crecimiento & desarrollo , Testículo/patología
16.
Acta Physiol (Oxf) ; 232(3): e13652, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33752256

RESUMEN

AIM: Highly prevalent diseases such as insulin resistance and heart failure are characterized by reduced metabolic flexibility and reserve. We tested whether Na/K-ATPase (NKA)-mediated regulation of Src kinase, which requires two NKA sequences specific to the α1 isoform, is a regulator of metabolic capacity that can be targeted pharmacologically. METHODS: Metabolic capacity was challenged functionally by Seahorse metabolic flux analyses and glucose deprivation in LLC-PK1-derived cells expressing Src binding rat NKA α1, non-Src-binding rat NKA α2 (the most abundant NKA isoform in the skeletal muscle), and Src binding gain-of-function mutant rat NKA α2. Mice with skeletal muscle-specific ablation of NKA α1 (skα1-/-) were generated using a MyoD:Cre-Lox approach and were subjected to treadmill testing and Western diet. C57/Bl6 mice were subjected to Western diet with or without pharmacological inhibition of NKA α1/Src modulation by treatment with pNaKtide, a cell-permeable peptide designed by mapping one of the sites of NKA α1/Src interaction. RESULTS: Metabolic studies in mutant cell lines revealed that the Src binding regions of NKA α1 are required to maintain metabolic reserve and flexibility. Skα1-/- mice had decreased exercise endurance and mitochondrial Complex I dysfunction. However, skα1-/- mice were resistant to Western diet-induced insulin resistance and glucose intolerance, a protection phenocopied by pharmacological inhibition of NKA α1-mediated Src regulation with pNaKtide. CONCLUSIONS: These results suggest that NKA α1/Src regulatory function may be targeted in metabolic diseases. Because Src regulatory capability by NKA α1 is exclusive to endotherms, it may link the aerobic scope hypothesis of endothermy evolution to metabolic dysfunction.


Asunto(s)
Dieta Occidental , ATPasa Intercambiadora de Sodio-Potasio/metabolismo , Animales , Ratones , Fragmentos de Péptidos , Ratas , Familia-src Quinasas/metabolismo
17.
Orthop Traumatol Surg Res ; 107(2): 102790, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33333269

RESUMEN

BACKGROUND: The Tape Locking Screw system (TLS) is a recognised technique used in anterior cruciate ligament reconstruction (ACLR). However, only a few previous studies have reported associated outcomes, all of which had been examined over a short-term period. The aim of this study was to assess the time-dependent changes in the objective and patient-reported outcome measures (PROM) in a group of patients with anterior cruciate ligament deficiency who have been operated on with this technique. HYPOTHESIS: Previously reported satisfactory short-term outcomes following TLS persist for several years after the operation. PATIENTS AND METHODS: This study was a retrospective observational study including 26 patients, who were followed after unilateral ACLR with TLS. Anterior tibial translation (ATT) was measured in both knees using the KT-1000 arthrometer and two PROMs: International Knee Documentation Committee (IKDC) and Lysholm subjective form scores were examined preoperatively, 6 months postoperatively, and annually for 5 years thereafter in all patients. RESULTS: One patient suffered a rupture of the graft, and one patient had a screw loosening. Two patients were lost for follow-up, so 22 patients were the final study group. Median (25-75%) ATT side-to-side differences between the injured and uninjured sides were 4 (3,5-4)mm preoperatively, 0,75 (0-1)mm 1 year postoperatively, and 0,75 (0-1)mm 5 years after the operation (P<0.001). Median (25-75%) IKDC scores were 44.25 (35.6-55.15), 92.55 (87.08-96.6), and 95.4 (90.8-97.7) points preoperatively and 1 year (P<0.001) and 5 years postoperatively, respectively. Median (25-75%) Lysholm scores were 52 (38.75-64.5), 95.5 (94.75-99.25), and 97.5 (95-99) points preoperatively and 1 year (P<0.001) and 5 years postoperatively, respectively. DISCUSSION: ACLR with TLS might already achieve favourable outcomes 1 year postoperatively, when measured objectively (ATT) and with PROMs. These outcomes persist 5 year postoperatively. LEVEL OF EVIDENCE IV: retrospective cohort study.


Asunto(s)
Lesiones del Ligamento Cruzado Anterior , Reconstrucción del Ligamento Cruzado Anterior , Lesiones del Ligamento Cruzado Anterior/cirugía , Tornillos Óseos , Estudios de Seguimiento , Humanos , Articulación de la Rodilla/cirugía , Medición de Resultados Informados por el Paciente , Estudios Retrospectivos , Resultado del Tratamiento
18.
Biol Reprod ; 103(2): 343-356, 2020 08 04.
Artículo en Inglés | MEDLINE | ID: mdl-32588885

RESUMEN

One of the mechanisms that cells have developed to fulfil their specialized tasks is to express different molecular variants of a particular protein that has unique functional properties. Na,K-ATPase (NKA), the ion transport mechanism that maintains the transmembrane Na+ and K+ concentrations across the plasma membrane of cells, is one of such protein systems that shows high molecular and functional heterogeneity. Four different isoforms of the NKA catalytic subunit are expressed in mammalian cells (NKAα1, NKAα2, NKAα3, and NKAα4). NKAα4 (ATP1A4) is the isoform with the most restricted pattern of expression, being solely produced in male germ cells of the testis. NKAα4 is abundant in spermatozoa, where it is required for sperm motility and hyperactivation. This review discusses the expression, functional properties, mechanism of action of NKAα4 in sperm physiology, and its role in male fertility. In addition, we describe the use of NKAα4 as a target for male contraception and a potential approach to pharmacologically block its ion transport function to interfere with male fertility.


Asunto(s)
Anticoncepción , Fertilidad/fisiología , ATPasa Intercambiadora de Sodio-Potasio/metabolismo , Motilidad Espermática/fisiología , Animales , Membrana Celular/metabolismo , Humanos , Capacitación Espermática/fisiología
19.
Comput Methods Programs Biomed ; 183: 105079, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31542688

RESUMEN

BACKGROUND: The image-based identification of distinct tissues within dermatological wounds enhances patients' care since it requires no intrusive evaluations. This manuscript presents an approach, we named QTDU, that combines deep learning models with superpixel-driven segmentation methods for assessing the quality of tissues from dermatological ulcers. METHOD: QTDU consists of a three-stage pipeline for the obtaining of ulcer segmentation, tissues' labeling, and wounded area quantification. We set up our approach by using a real and annotated set of dermatological ulcers for training several deep learning models to the identification of ulcered superpixels. RESULTS: Empirical evaluations on 179,572 superpixels divided into four classes showed QTDU accurately spot wounded tissues (AUC = 0.986, sensitivity = 0.97, and specificity = 0.974) and outperformed machine-learning approaches in up to 8.2% regarding F1-Score through fine-tuning of a ResNet-based model. Last, but not least, experimental evaluations also showed QTDU correctly quantified wounded tissue areas within a 0.089 Mean Absolute Error ratio. CONCLUSIONS: Results indicate QTDU effectiveness for both tissue segmentation and wounded area quantification tasks. When compared to existing machine-learning approaches, the combination of superpixels and deep learning models outperformed the competitors within strong significant levels.


Asunto(s)
Aprendizaje Profundo , Dermatología/métodos , Diagnóstico por Computador/métodos , Procesamiento de Imagen Asistido por Computador/métodos , Reconocimiento de Normas Patrones Automatizadas/métodos , Úlcera Cutánea/diagnóstico por imagen , Algoritmos , Área Bajo la Curva , Teorema de Bayes , Humanos , Aprendizaje Automático , Análisis de Componente Principal , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Máquina de Vectores de Soporte
20.
Steroids ; 155: 108551, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31812624

RESUMEN

Cardiotonic steroids (CTS) are agents traditionally known for their capacity to bind to the Na,K-ATPase (NKA), affecting the ion transport and the contraction of the heart. Natural CTS have been shown to also have effects on cell signaling pathways. With the goal of developing a new CTS derivative, we synthesized a new digoxin derivative, 21-benzylidene digoxin (21-BD). Previously, we have shown that this compound binds to NKA and has cytotoxic actions on cancer, but not on normal cells. Here, we further studied the mechanisms of actions of 21-BD. Working with HeLa cells, we found that 21-BD decreases the basal, as well as the insulin stimulated proliferation. 21-BD reduces phosphorylation of the epidermal growth factor receptor (EGFR) and extracellular-regulated kinase (ERK), which are involved in pathways that stimulate cell proliferation. In addition, 21-BD promotes apoptosis, which is mediated by the translocation of Bax from the cytosol to mitochondria and the release of mitochondrial cytochrome c to the cytosol. 21-BD also activated caspases-8, -9 and -3, and induced the cleavage of poly (ADP-ribose) polymerase-1 (PARP-1). Altogether, these results show that the new compound that we have synthesized exerts cytotoxic actions on HeLa cells by inhibition of cell proliferation and the activation of both the extrinsic and intrinsic apoptotic pathways. These results support the relevance of the cardiotonic steroid scaffold as modulators of cell signaling pathways and potential agents for their use in cancer.


Asunto(s)
Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Digoxina/análogos & derivados , Quinasas MAP Reguladas por Señal Extracelular/antagonistas & inhibidores , Inhibidores de Proteínas Quinasas/farmacología , Antineoplásicos/química , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Digoxina/química , Digoxina/farmacología , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Receptores ErbB/antagonistas & inhibidores , Receptores ErbB/metabolismo , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Células HeLa , Humanos , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Conformación Molecular , Inhibidores de Proteínas Quinasas/química , Transducción de Señal/efectos de los fármacos , Relación Estructura-Actividad , Células Tumorales Cultivadas
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