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2.
Clin Genitourin Cancer ; 22(5): 102140, 2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-39018723

RESUMEN

BACKGROUND: Optimal drug selection for metastatic hormone-sensitive prostate cancer (mHSPC) remains unclear. We therefore assessed the clinical outcomes of mHSPC treated with new-generation androgen receptor pathway inhibitors (ARSIs) and identified risk factors associated with the prognosis of mHSPC. METHODS: We retrospectively reviewed 324 patients with mHSPC who were treated with ARSIs, including abiraterone acetate, enzalutamide, and apalutamide, between January 2018 and December 2022. In addition to assessing the prostate-specific antigen (PSA) response and overall survival (OS) during ARSI treatment, we investigated several potential risk factors for a poor OS in patients with mHSPC. RESULTS: Patients with a ≥ 90% PSA reduction (hazard ratio [HR]: 0.24, 95% confidence interval [CI], 0.10-0.58; P = .002) and those whose PSA declined to ≤ 0.2 ng/mL (HR: 0.22, 95% CI, 0.08-0.63; P = .005) showed significantly better OS than other patients. Gleason grade group 5 (GG5), presence of liver metastasis, and an LDH ≥ 250 U/L were identified as prognostic factors significantly associated with a poor OS, with HRs of 2.31 (95% CI, 1.02-5.20; P = .044), 7.87 (95% CI, 2.61-23.8; P < .001) and 3.21 (95% CI, 1.43-7.23; P = .005). CONCLUSION: We identified GG5, the presence of liver metastasis, and elevated LDH at the diagnosis as significant factors predicting the OS of mHSPC, but the choice of ARSIs did not affect the prognosis. The potential prognostic impact of these markers requires further investigation.

3.
Int J Urol ; 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39007529

RESUMEN

BACKGROUND: Surgical resection for pheochromocytoma (PCC) is still challenging. This study assessed the perioperative outcomes of adrenalectomy for PCC and investigated the risk factors for intraoperative hemodynamic instability (HI). METHODS: This retrospective study included 571 patients with adrenal tumors who underwent adrenalectomy at Kobe University Hospital and other related hospitals between April 2008 and October 2023. The perioperative outcomes of laparoscopic adrenalectomy were compared between PCC (n = 92) and non-PCC (n = 464) groups. In addition, we investigated several potential risk factors for intraoperative HI in patients with PCC (n = 107; open, n = 11; laparoscopic, n = 92; robot-assisted, n = 4). RESULTS: While patients with PCC had a significantly larger amount of blood loss in comparison to those with non-PCC (mean, 70 and 30 mL, respectively; p = 0.004), no significant difference was observed in the rate of perioperative grade ≥III complications (1.1% vs. 0.6%; p = 0.516), and no perioperative mortality was observed in either group. A tumor size of ≥40 mm, with preoperative hypertension and urinary metanephrines at a level ≥3 times the upper limit of the normal value, were found to be significant predictors of HI, with odds ratios of 2.74 (p = 0.025), 3.91 (p = 0.005), and 3.83 (p = 0.004), respectively. CONCLUSIONS: Our data suggest that laparoscopic adrenalectomy for PCC may be as safe as that for other types of adrenal tumors and that large tumors and hormonally active disease may be risk factors for intraoperative HI. The optimal perioperative management for PCC with these risk factors should be established.

4.
Cureus ; 16(4): e58558, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38770464

RESUMEN

Premature chromatid separation (PCS)/mosaic variegated aneuploidy (MVA) syndrome is a rare chromosome instability syndrome. This syndrome is inherited in an autosomal recessive pattern. Although heterozygous carriers of a monoallelic mutation reportedly have a normal phenotype, PCS-positive cells are found at a higher rate in such carriers than in the general population. We herein report a case in which a PCS carrier was incidentally diagnosed during investigation of male infertility. A diagnosis of nonobstructive azoospermia was made, and chromosome analysis revealed the PCS trait in 81 of 200 cells (40.5%), indicating that the patient was a PCS carrier. PCS carriers are not uncommon, and if both members of a couple are carriers, there would be a 25% likelihood of the child presenting with PCS syndrome. Therefore, a clinical psychological approach that includes genetic counseling should be considered before proceeding to microsurgical testicular sperm extraction.

5.
World J Mens Health ; 42(1): 92-132, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37382284

RESUMEN

PURPOSE: The purpose of this meta-analysis is to study the impact of varicocele repair in the largest cohort of infertile males with clinical varicocele by including all available studies, with no language restrictions, comparing intra-person conventional semen parameters before and after the repair of varicoceles. MATERIALS AND METHODS: The meta-analysis was performed according to PRISMA-P and MOOSE guidelines. A systematic search was performed in Scopus, PubMed, Cochrane, and Embase databases. Eligible studies were selected according to the PICOS model (Population: infertile male patients with clinical varicocele; Intervention: varicocele repair; Comparison: intra-person before-after varicocele repair; Outcome: conventional semen parameters; Study type: randomized controlled trials [RCTs], observational and case-control studies). RESULTS: Out of 1,632 screened abstracts, 351 articles (23 RCTs, 292 observational, and 36 case-control studies) were included in the quantitative analysis. The before-and-after analysis showed significant improvements in all semen parameters after varicocele repair (except sperm vitality); semen volume: standardized mean difference (SMD) 0.203, 95% CI: 0.129-0.278; p<0.001; I²=83.62%, Egger's p=0.3329; sperm concentration: SMD 1.590, 95% CI: 1.474-1.706; p<0.001; I²=97.86%, Egger's p<0.0001; total sperm count: SMD 1.824, 95% CI: 1.526-2.121; p<0.001; I²=97.88%, Egger's p=0.0063; total motile sperm count: SMD 1.643, 95% CI: 1.318-1.968; p<0.001; I²=98.65%, Egger's p=0.0003; progressive sperm motility: SMD 1.845, 95% CI: 1.537%-2.153%; p<0.001; I²=98.97%, Egger's p<0.0001; total sperm motility: SMD 1.613, 95% CI 1.467%-1.759%; p<0.001; l2=97.98%, Egger's p<0.001; sperm morphology: SMD 1.066, 95% CI 0.992%-1.211%; p<0.001; I²=97.87%, Egger's p=0.1864. CONCLUSIONS: The current meta-analysis is the largest to date using paired analysis on varicocele patients. In the current meta-analysis, almost all conventional semen parameters improved significantly following varicocele repair in infertile patients with clinical varicocele.

6.
Biosci Microbiota Food Health ; 42(3): 213-221, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37404567

RESUMEN

A placebo-controlled, randomized, double-blind study was conducted to evaluate the effect of taking 25 billion colony-forming units of heat-killed Bifidobacterium longum CLA8013 over 2 weeks on bowel movements in constipation-prone healthy individuals. The primary endpoint was the change in defecation frequency between the baseline and 2 weeks after the intake of B. longum CLA8013. The secondary endpoints were the number of days of defecation, stool volume, stool consistency, straining during defecation, pain during defecation, feeling of incomplete evacuation after defecation, abdominal bloating, fecal water content, and the Japanese version of the Patient Assessment of Constipation Quality of Life. A total of 120 individuals were assigned to two groups, 104 (control group, n=51; treatment group, n=53) of whom were included in the analysis. After 2 weeks of consuming the heat-killed B. longum CLA8013, defecation frequency increased significantly in the treatment group compared with that in the control group. Furthermore, compared with the control group, the treatment group showed a significant increase in stool volume and significant improvement in stool consistency, straining during defecation, and pain during defecation. No adverse events attributable to the heat-killed B. longum CLA8013 were observed during the study period. This study revealed that heat-killed B. longum CLA8013 improved the bowel movements of constipation-prone healthy individuals and confirmed that there were no relevant safety issues.

7.
Urol Case Rep ; 47: 102368, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36915704

RESUMEN

Congenital adrenal hyperplasia (CAH) causes hypogonadotropic hypogonadism due to the excessive production of adrenal androgens, which results in hypospermatogenesis in some male patients. We herein present a CAH case with hypogonadotropic hypogonadism and male infertility. A 26-year-old male receiving steroid therapy for 21 hydroxylase deficiency was diagnosed with low gonadotropin levels, an elevated ACTH level, and severe oligozoospermia. The switching from hydrocortisone to dexamethasone resulted in the normalization of gonadotropin levels and semen findings. The couple underwent ICSI-ET, resulting in a live birth. In cases of CAH with hypospermatogenesis, the continuous suppression of ACTH by dexamethasone may restore spermatogenesis.

9.
J Nutr Sci Vitaminol (Tokyo) ; 68(2): 112-119, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35491200

RESUMEN

It is well known that branched-chain amino acids (BCAAs) promote protein synthesis in skeletal muscle and can cause muscle hypertrophy. However, it has also been reported that they may inhibit muscle atrophy induced by load-bearing and age-related changes. In this study, we investigated the effects of BCAA intake during joint fixation on the levels of protein kinase B (Akt), mammalian target of rapamycin (mTOR), and nebulin in a rat model of joint fixation. Akt and mTOR are signal factors of protein synthesis, whereas nebulin is a structural protein in the muscle. The effects of BCAAs on muscle atrophy were also investigated. The phosphorylation rate of mTOR was higher than that of Akt and increased with BCAA intake in the rat hind limb muscles (soleus) when the ankle joint was fixed. The relative level of nebulin and the phosphorylation rate of Neural Wiskott-Aldrich syndrome protein (N-WASP) also increased as a result of BCAA intake during fixation. This is important because nebulin and N-WASP are involved in the formation of the structure of sarcomere thin filaments. Furthermore, when the cross-sectional areas (CSAs) of different types of muscle fibers were measured during histological evaluation of muscle atrophy, it was found that the inhibitory effect of BCAA on muscle atrophy was higher in Type 1 fibers. Additionally, a positive correlation was found between nebulin level and the CSAs of the muscle fibers. It was found that there is a close relationship between the content of structural proteins and muscle atrophy.


Asunto(s)
Aminoácidos de Cadena Ramificada , Proteínas Proto-Oncogénicas c-akt , Animales , Mamíferos/metabolismo , Proteínas Musculares , Atrofia Muscular/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Ratas , Serina-Treonina Quinasas TOR
10.
Biochem Biophys Res Commun ; 603: 123-129, 2022 05 07.
Artículo en Inglés | MEDLINE | ID: mdl-35287053

RESUMEN

BACKGROUND: Cisplatin (CDDP) is an effective anticancer drug for the treatment of malignant tumors, such as lung cancer, bladder cancer, and testicular cancer. However, oligozoospermia and azoospermia after administration of CDDP are clinical problems. One of the testicular toxicities of CDDP is known to cause oxidative stress. Tadalafil has been reported to exhibit antioxidant effects and is widely used in clinical practice to treat benign prostatic hyperplasia and erectile dysfunction. Rho-kinase α (ROCK2) regulates cell migration and apoptosis and has been reported to be involved in CDDP-induced nephrotoxicity. The excessive expression of ROCK2 is known to cause oxidative stress. OBJECTIVE: The objective of the current study was to test the effect of tadalafil on the testicular toxicity of CDDP. MATERIAL AND METHODS: Thirty-two rats were used and divided into the following four groups. (1) The control group (CONT), treated with saline on day 1 and saline and dimethyl sulfoxide (DMSO) on days 1-10 intraperitoneally (i.p.) (2) The Tadalafil Group (TAD), treated with saline on day 1, and 0.4 mg/kg tadalafil on days 1-10 i.p. (3) The CDDP group (CD), treated with 7 mg/kg CDDP, saline, and DMSO on days 1-10 i.p. and (4) The CDDP + TAD group (CDT) was treated with 7 mg/kg CDDP on day 1, and 0.4 mg/kg tadalafil on days 1-10 i.p. Testes and epididymides samples were collected on day 11. Biochemical and pathological analyses and quantitative polymerase chain reaction were performed on the excised specimens. RESULTS: CDDP treatment resulted in testicular atrophy, decreased sperm concentration, and atrophy of seminiferous tubules as observed from the testicular histology. Increased apoptosis of seminiferous tubules, oxidative stress, and ROCK2 mRNA expression were observed after CDDP treatment. Treatment with tadalafil improved these adverse effects. CONCLUSION: Tadalafil is a potential drug for reducing CDDP-induced spermatogenic dysfunction. The antioxidant effect of tadalafil may be partly responsible for this phenomenon. ROCK2 and oxidative stress markers may be involved in the possible antioxidant effects of tadalafil. Tadalafil may be considered as one of a treatment option for reducing spermatogenic dysfunction after administration of CDDP.


Asunto(s)
Cisplatino , Neoplasias Testiculares , Animales , Antioxidantes/farmacología , Atrofia , Cisplatino/efectos adversos , Dimetilsulfóxido/farmacología , Humanos , Masculino , Estrés Oxidativo , Ratas , Tadalafilo/farmacología , Tadalafilo/uso terapéutico
11.
Physiol Rep ; 9(18): e15046, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34558206

RESUMEN

Diabetic skeletal muscles show reduced contractile force and increased fatigability. Hands are a target for several diabetes-induced complications. Therefore, reduced handgrip strength often occurs as a consequence of diabetes. The aim of this study was to examine whether long-term exercise can prevent reduction of grip strength in type 2 diabetes mellitus (T2DM) model OLETF rats, and to explore the mechanisms underlying diabetes-induced grip strength reduction. Ten 5-week-old OLETF rats were used as experimental animals, and five non-diabetic LETO rats as controls of OLETF rats. Half OLETF rats performed daily voluntary wheel-running for 17 months (OLETF + EXE), and the rest of OLETF and LETO rats were sedentary. Grip strength was higher in OLETF + EXE and LETO groups than in OLETF group. OLETF group with hyperglycemia showed an increase in HbA1c, serum TNF-α, and muscle SERCA activity, but a decrease in circulating insulin. Each fiber area, total fiber area, and % total fiber area in type IIb fibers of extensor digitorum longus muscles were larger in OLETF + EXE and LETO groups than in OLETF group. There was a positive correlation between grip strength and the above three parameters concerning type IIb fiber area. Therefore, type IIb fiber atrophy may be the major direct cause of grip strength reduction in OLETF group, although there seems multiple etiological mechanisms. Long-term wheel-running may have blocked the diabetes-induced reduction of grip strength by preventing type IIb fiber atrophy. Regular exercise may be a potent modality for preventing not only the progression of diabetes but muscle dysfunction in T2DM patients.


Asunto(s)
Diabetes Mellitus Experimental/fisiopatología , Diabetes Mellitus Tipo 2/fisiopatología , Fuerza de la Mano , Atrofia Muscular/prevención & control , Condicionamiento Físico Animal/métodos , Carrera , Animales , Diabetes Mellitus Experimental/complicaciones , Diabetes Mellitus Tipo 2/complicaciones , Masculino , Músculo Esquelético/fisiopatología , Atrofia Muscular/etiología , Ratas , Ratas Long-Evans
12.
Arerugi ; 70(4): 310-314, 2021.
Artículo en Japonés | MEDLINE | ID: mdl-34135254

RESUMEN

A 12-year-old boy visited our hospital with complaints of chronic cough and dyspnea. Chest X-ray and CT revealed diffuse granular shadow in the bilateral lung fields and "Tree-in-bud appearance" in the peripheral airways, respectively. Sinusitis was present, and restrictive disorder was predominantly found in pulmonary function. The patient was diagnosed with DPB, and long-term therapy was started with low-dose clarithromycin (CAM), The patient showed a dramatic response to CAM, with improvements of both the clinical symptoms and pulmonary function within 1-2 months. According to the relevant literature, in adult patients with this disease, pulmonary dysfunction starts from an obstructive pattern; however, this is not the case in pediatric patients. It was therefore suggested that the mechanisms underlying the development of pulmonary dysfunction in cases of childhood onset differs from those with an adult onset.


Asunto(s)
Bronquiolitis , Infecciones por Haemophilus , Adulto , Bronquiolitis/tratamiento farmacológico , Niño , Humanos , Macrólidos , Masculino , Organización Mundial de la Salud
13.
Arerugi ; 70(3): 210-214, 2021.
Artículo en Japonés | MEDLINE | ID: mdl-34011776

RESUMEN

We experienced a case of vocal cord dysfunction (VCD) in a child to whom an adrenaline autoinjector (Epipen®) had been prescribed and frequently used following a diagnosis of exercise-induced anaphylaxis. An exercise test was performed to investigate her frequent episodes of anaphylaxis-like symptoms. A few minutes after starting the test, signs of dyspnea, such as throat tightness and stridor, appeared, although hypoxia was not present and her respiratory sounds were normal. Medications were not effective for treating her respiratory symptoms. Laryngoscopy performed at the test revealed bizarre vocal cord movement, which was diagnosed as VCD. The symptoms gradually diminished after the initiation of biofeedback therapy, including pursed lips breathing and abdominal breathing. Thereafter, she did not use an adrenaline autoinjector when symptoms appeared; instead, she would perform biofeedback therapy before using the adrenaline autoinjector. Thus, VCD should be included in the differential diagnosis of patients who show anaphylactic symptoms that are resistant to preventive therapy.


Asunto(s)
Anafilaxia , Disfunción de los Pliegues Vocales , Anafilaxia/diagnóstico , Anafilaxia/tratamiento farmacológico , Anafilaxia/etiología , Niño , Diagnóstico Diferencial , Disnea/diagnóstico , Disnea/etiología , Epinefrina , Femenino , Humanos , Disfunción de los Pliegues Vocales/diagnóstico , Organización Mundial de la Salud
14.
Biochim Biophys Acta Biomembr ; 1862(10): 183403, 2020 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-32585206

RESUMEN

The left-handed, extended polyproline II (PPII) helix is a unique secondary structure which potently modulates peptide/protein functions through its constraint conformation. To investigate the effect of PPII helix on the direct cell membrane penetration of arginine-rich peptides, we designed a polyproline-containing arginine-rich peptide P9R7W (PPPPPPPPPRRRRRRRW) by introducing nine proline residues into a linear R7W (RRRRRRRW) peptide. Circular dichroism spectroscopy showed that P9R7W has the PPII helix structure in solution whereas R7W is predominantly in random coil structure. Tryptophan fluorescence measurements demonstrated that P9R7W binds to negatively charged lipid vesicles with similar affinity to R7W, in which there was no significant change in the PPII helix structure. Flow cytometry and confocal laser scanning microscopy analyses showed that P9R7W has an ability to penetrate into CHO-K1 cells more efficiently compared to R7W with no cytotoxicity. Consistently, a channel current analysis unveiled that P9R7W penetrates planar lipid bilayer membranes more efficiently than R7W without significant membrane perturbation. Our results indicate that the PPII helix structure can enhance the membrane penetration efficiency of arginine-rich peptides without lipid membrane perturbation.


Asunto(s)
Arginina/química , Péptidos/química , Secuencia de Aminoácidos , Animales , Células CHO , Cricetulus , Conformación Proteica , Espectrometría de Fluorescencia , Porcinos
15.
J Surg Case Rep ; 2020(6): rjaa165, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32582434

RESUMEN

Sarcomas and related proliferative lesions of the specialized stroma of the prostate are very rare and have been classified into prostate stromal sarcoma (PSS) and prostatic stromal tumor of uncertain malignant potential based on histology. We herein describe a case of PSS. A 40-year-old male presented at a hospital with urinary distention. Magnetic resonance imaging revealed a large prostate mass, and the diagnosis was prostate sarcoma of uncertain differentiation by ultrasound-guided needle biopsy. Total pelvic exenteration was performed and a pathological diagnosis of PSS was ultimately reached. Ten months later, there have been no signs of metastasis or recurrence.

16.
Andrologia ; 52(1): e13489, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31777105

RESUMEN

A 27-year-old man with nonobstructive azoospermia was diagnosed with Klinefelter syndrome (KS) with a satellite Y chromosome (47, XXYqs) by karyotyping. Genetic analysis revealed azoospermia factor c (AZFc) microdeletion of gr/gr deletion in the Y chromosome. Microdissection testicular sperm extraction (micro-TESE) was performed in bilateral testes. Very few seminiferous tubules were bilaterally observed, and a minute number of spermatozoa obtained from the left testis were cryopreserved. Histologic examination of the left testicular tissue revealed severe tubular atrophy with only Sertoli cells accompanied by Leydig cell hyperplasia. Oocyte harvest was conducted in his wife in two different cycles after ovarian stimulation, and intracytoplasmic sperm injection was performed for 24 oocytes (8 and 16 oocytes respectively) using thawed spermatozoa. Fertilisation was confirmed in total of 19 oocytes (79.2%), with 15 cleaved embryos (62.5%). Two cleavage-stage embryos were cryopreserved at day 2, but no blastocysts developed. Frozen-thawed embryo transfer was performed using two cleavage-stage (day 2) embryos; however, the wife did not conceive. In conclusion, spermatozoa were successfully obtained by micro-TESE from a patient with 47, XXYqs. Despite failure of conception, the fertilisation and cleavage rates were comparable or better than those reported in patients with "typical" KS.


Asunto(s)
Síndrome de Klinefelter/terapia , Recuperación de la Esperma , Adulto , Cromosomas Humanos Y/genética , Femenino , Humanos , Cariotipificación , Síndrome de Klinefelter/diagnóstico , Síndrome de Klinefelter/genética , Masculino , Microdisección/métodos , Inyecciones de Esperma Intracitoplasmáticas , Resultado del Tratamiento
17.
Nucleic Acids Res ; 47(20): 10942-10955, 2019 11 18.
Artículo en Inglés | MEDLINE | ID: mdl-31586407

RESUMEN

The complex between Trm7 and Trm734 (Trm7-Trm734) from Saccharomyces cerevisiae catalyzes 2'-O-methylation at position 34 in tRNA. We report biochemical and structural studies of the Trm7-Trm734 complex. Purified recombinant Trm7-Trm734 preferentially methylates tRNAPhe transcript variants possessing two of three factors (Cm32, m1G37 and pyrimidine34). Therefore, tRNAPhe, tRNATrp and tRNALeu are specifically methylated by Trm7-Trm734. We have solved the crystal structures of the apo and S-adenosyl-L-methionine bound forms of Trm7-Trm734. Small angle X-ray scattering reveals that Trm7-Trm734 exists as a hetero-dimer in solution. Trm7 possesses a Rossmann-fold catalytic domain, while Trm734 consists of three WD40 ß-propeller domains (termed BPA, BPB and BPC). BPA and BPC form a unique V-shaped cleft, which docks to Trm7. The C-terminal region of Trm7 is required for binding to Trm734. The D-arm of substrate tRNA is required for methylation by Trm7-Trm734. If the D-arm in tRNAPhe is docked onto the positively charged area of BPB in Trm734, the anticodon-loop is located near the catalytic pocket of Trm7. This model suggests that Trm734 is required for correct positioning of tRNA for methylation. Additionally, a point-mutation in Trm7, which is observed in FTSJ1 (human Trm7 ortholog) of nosyndromic X-linked intellectual disability patients, decreases the methylation activity.


Asunto(s)
ARN de Transferencia/metabolismo , Proteínas de Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/enzimología , Proteínas de Transporte Vesicular/química , ARNt Metiltransferasas/química , Dominio Catalítico , Enlace de Hidrógeno , Metilación , Modelos Moleculares , Proteínas Mutantes/química , Proteínas Mutantes/metabolismo , Unión Proteica , Subunidades de Proteína/química , Pirimidinas/metabolismo , Proteínas Recombinantes/metabolismo , S-Adenosilmetionina/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Especificidad por Sustrato , Proteínas de Transporte Vesicular/metabolismo , ARNt Metiltransferasas/metabolismo
18.
Commun Biol ; 2: 209, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31240247

RESUMEN

Rhodopsin is a G protein-coupled receptor (GPCR) that initiates the phototransduction cascade in retinal disc membrane. Recent studies have suggested that rhodopsin forms highly ordered rows of dimers responsible for single-photon detection by rod photoreceptors. Dimerization is also known to confer to rhodopsin a high affinity for ordered lipids (raftophilicity). However, the role of rhodopsin organization and its raftophilicity in phototransduction remains obscure, owing to the lack of direct observation of rhodopsin dynamics and distribution in native discs. Here, we explore the single-molecule and semi-multimolecule behaviour of rhodopsin in native discs. Rhodopsin forms transient meso-scale clusters, even in darkness, which are loosely confined to the disc centre. Cognate G protein transducin co-distributes with rhodopsin, and exhibits lateral translocation to the disc periphery upon activation. We demonstrate that rhodopsin offers inherently distributed and stochastic platforms for G protein signalling by self-organizing raftophilic clusters, which continually repeat generation/extinction in the disc membrane.


Asunto(s)
Proteínas de Unión al GTP/metabolismo , Microdominios de Membrana/química , Retina/metabolismo , Rodopsina/química , Segmento Externo de la Célula en Bastón/metabolismo , Animales , Anticuerpos/química , Membrana Celular/metabolismo , Colesterol/química , Biología Computacional , Guanosina Trifosfato/química , Luz , Fototransducción , Multimerización de Proteína , Transporte de Proteínas , Ranidae , Receptores Acoplados a Proteínas G/metabolismo , Células Fotorreceptoras Retinianas Bastones/metabolismo , Rodopsina/metabolismo , Transducción de Señal , Procesos Estocásticos
19.
Andrologia ; 51(5): e13241, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30706522

RESUMEN

Mirabegron is a selective beta3-adrenoceptor (ß3 -AR) agonist, which is commonly used for the treatment of overactive bladder. This medicine is associated with atrophy of reproductive organs in rats. However, no study has examined the detailed action and mechanism of its toxicity in reproductive cells. In this study, we examined the effect of mirabegron on primary cultured rat Sertoli cells. Firstly, RT-PCR and immunocytochemistry revealed that ß3 -AR was present in rat Sertoli cells. Then, primary cultured rat Sertoli cells were treated with mirabegron. Quantitative real-time PCR revealed that mirabegron treatment induced a significant increase in claudin-11 mRNA, which is crucial for spermatogenesis. Western blot analysis also showed that mirabegron treatment significantly activated p44/42 mitogen-activated protein kinase (MAPK). After additional treatment with U0126, a specific noncompetitive inhibitor of mitogen-activated protein kinase kinase (MAPKK), the upregulation of claudin-11 mRNA induced by mirabegron was reduced. At the same time, immunocytochemistry showed mirabegron treatment disturbed claudin-11 localisation to tight junction, which was recovered when treated with mirabegron in the presence of U0126. These results suggest that mirabegron treatment is associated with assembly of the blood-testis barrier through p44/42 MAPK pathway. These findings could explain one of the underlying mechanisms of reproductive toxicity induced by mirabegron.


Asunto(s)
Acetanilidas/toxicidad , Agonistas de Receptores Adrenérgicos beta 3/toxicidad , Barrera Hematotesticular/efectos de los fármacos , Células de Sertoli/efectos de los fármacos , Tiazoles/toxicidad , Uniones Estrechas/efectos de los fármacos , Animales , Butadienos/farmacología , Células Cultivadas , Claudinas/metabolismo , Masculino , Proteína Quinasa 1 Activada por Mitógenos/antagonistas & inhibidores , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos/antagonistas & inhibidores , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Nitrilos/farmacología , Cultivo Primario de Células , Ratas , Ratas Sprague-Dawley , Células de Sertoli/citología , Células de Sertoli/metabolismo , Transducción de Señal/efectos de los fármacos , Espermatogénesis/efectos de los fármacos , Uniones Estrechas/metabolismo
20.
World J Mens Health ; 37(2): 166-174, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30588779

RESUMEN

The survival rates of boys and men with cancer have increased due to advances in cancer treatments; however, maintenance of quality of life, including fertility preservation, remains a major issue. Fertile male patients who receive radiation and/or chemotherapy face temporary, long-term, or permanent gonadal damage, particularly with exposure to alkylating agents and whole-body irradiation, which sometimes induce critical germ cell damage. These cytotoxic treatments have a significant impact on a patient's ability to have their own biological offspring, which is of particular concern to cancer patients of reproductive age. Therefore, various strategies are needed in order to preserve male fertility. Sperm cryopreservation is an effective method for preserving spermatozoa. Advances have also been achieved in pre-pubertal germ cell storage and research to generate differentiated male germ cells from various types of stem cells, including embryonic stem cells, induced pluripotent stem cells, and spermatogonial stem cells. These approaches offer hope to many patients in whom germ cell loss is associated with sterility, but are still experimental and preliminary. This review examines the current understanding of the effects of chemotherapy and radiation on male fertility.

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