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1.
Int J Mol Sci ; 23(10)2022 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-35628594

RESUMEN

Ototoxicity is one of the main dose-limiting side effects of cisplatin chemotherapy and impairs the quality of life of tumor patients dramatically. Since there is currently no established standard therapy targeting hearing loss in cisplatin treatment, the aim of this study was to investigate the effect of nimodipine and its role in cell survival in cisplatin-associated hearing cell damage. To determine the cytotoxic effect, the cell death rate was measured using undifferentiated and differentiated UB/OC-1 and UB/OC-2 cells, after nimodipine pre-treatment and stress induction by cisplatin. Furthermore, immunoblot analysis and intracellular calcium measurement were performed to investigate anti-apoptotic signaling, which was associated with a reduced cytotoxic effect after nimodipine pre-treatment. Cisplatin's cytotoxic effect was significantly attenuated by nimodipine up to 61%. In addition, nimodipine pre-treatment counteracted the reduction in LIM Domain Only 4 (LMO4) by cisplatin, which was associated with increased activation of Ak strain transforming/protein kinase B (Akt), cAMP response element-binding protein (CREB), and signal transducers and activators of transcription 3 (Stat3). Thus, nimodipine presents a potentially well-tolerated substance against the ototoxicity of cisplatin, which could result in a significant improvement in patients' quality of life.


Asunto(s)
Antineoplásicos , Ototoxicidad , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Antineoplásicos/efectos adversos , Antineoplásicos/metabolismo , Apoptosis , Cisplatino/farmacología , Células Ciliadas Auditivas/metabolismo , Humanos , Proteínas con Dominio LIM/genética , Proteínas con Dominio LIM/metabolismo , Nimodipina/farmacología , Calidad de Vida , Regulación hacia Arriba
2.
Trials ; 22(1): 475, 2021 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-34294114

RESUMEN

BACKGROUND: A previously performed phase III trial on 112 subjects investigating prophylactic nimodipine treatment in vestibular schwannoma (VS) surgery showed no clear beneficial effects on preservation of facial and cochlear nerve functions, though it should be considered that protection of facial nerve function was the primary outcome. However, the risk for postoperative hearing loss was halved in the nimodipine group compared to the control group (OR 0.49; 95% CI 0.18-1.30; p = 0.15). Accordingly, this phase III extension trial investigates the efficacy and safety of prophylactic nimodipine for hearing preservation in VS surgery. METHODS: This is a randomized, multi-center, two-armed, open-label phase III trial with blinded expert review and two-stage with interim analysis. Three hundred thirty-six adults with the indication for microsurgical removal of VS (Koos I-IV) and serviceable preoperative hearing (Gardner-Robertson scale (GR) 1-3) are assigned to either the therapy (intravenous nimodipine 1-2 mg/h from the day before surgery until the fifth postoperative day and standard of care) or the control group (surgery only and standard of care). The primary endpoint of the trial is postoperative cochlear nerve function measured before discharge according to GR 1-3 versus GR 4-5 (binary). Hearing function will be determined by pre- and postoperative audiometry with speech discrimination, which will be evaluated by a blinded expert reviewer. Furthermore, patient-reported outcomes using standardized questionnaires will be analyzed. DISCUSSION: Prophylactic parenteral nimodipine treatment may have a positive effect on hearing preservation in VS surgery and would improve patient's quality of life. Further secondary analyses are planned. Except for dose-depending hypotension, nimodipine is known as a safe drug. In the future, prophylactic nimodipine treatment may be recommended as a routine medication in VS surgery. VS can be considered as an ideal model for clinical evaluation of neuroprotection, since hearing outcome can be classified by well-recognized criteria. The beneficial effect of nimodipine may be transferable to other surgical procedures with nerves at risk and may have impact on basic research. TRIAL REGISTRATION: EudraCT 2019-002317-19, DRKS00019107 . 8th May 2020.


Asunto(s)
Neuroma Acústico , Nimodipina , Adulto , Ensayos Clínicos Fase III como Asunto , Audición , Humanos , Estudios Multicéntricos como Asunto , Neuroma Acústico/diagnóstico , Neuroma Acústico/cirugía , Nimodipina/efectos adversos , Complicaciones Posoperatorias , Calidad de Vida , Ensayos Clínicos Controlados Aleatorios como Asunto , Estudios Retrospectivos , Resultado del Tratamiento
3.
Neurosurg Rev ; 44(3): 1729-1735, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32827307

RESUMEN

A 2016 published randomized multicenter phase III trial of prophylactic nimodipine treatment in vestibular schwannoma surgery showed only a tendency for higher hearing preservation rates in the treatment group. Gender was not included in statistical analysis at that time. A retrospective analysis of the trial considering gender, preoperative hearing, and nimodipine treatment was performed. The treatment group received parenteral nimodipine from the day before surgery until the seventh postoperative day. The control group was not treated prophylactically. Cochlear nerve function was determined by pure-tone audiometry with speech discrimination preoperatively, during in-patient care, and 1 year after surgery and classified according to the Gardner-Robertson grading scale (GR). Logistic regression analysis showed a statistically significant effect for higher hearing preservation rates (pre- and postoperative GR 1-4) in 40 men comparing the treatment (n = 21) and the control (n = 19) groups (p = 0.028), but not in 54 women comparing 27 women in both groups (p = 0.077). The results were also statistically significant for preservation of postoperative hearing with pre- and postoperative GR 1-3 (p = 0.024). There were no differences in tumor sizes between the treatment and the control groups in men, whereas statistically significant larger tumors were observed in the female treatment group compared with the female control group. Prophylactic nimodipine is safe, and an effect for hearing preservation in 40 men with preoperative hearing ability of GR 1-4 was shown in this retrospective investigation. The imbalance in tumor size with larger tumors in females of the treatment group may falsely suggest a gender-related effect. Further investigations are recommended to clarify whether gender has impact on nimodipine's efficacy.


Asunto(s)
Audición/efectos de los fármacos , Neuroma Acústico/tratamiento farmacológico , Neuroma Acústico/cirugía , Nimodipina/administración & dosificación , Profilaxis Pre-Exposición/tendencias , Adulto , Anciano , Femenino , Audición/fisiología , Pruebas Auditivas/tendencias , Humanos , Masculino , Persona de Mediana Edad , Neuroma Acústico/diagnóstico , Estudios Prospectivos , Radiocirugia/métodos , Estudios Retrospectivos , Método Simple Ciego , Resultado del Tratamiento
4.
J Craniomaxillofac Surg ; 45(12): 1948-1954, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29037922

RESUMEN

PURPOSE: Cleft lip and palate (CL/P) are one of the most common human birth defects. Animal experiments and clinical investigations show a clear reduction of teratogenic clefts by a high-dose vitamin B supplementation during early pregnancy, especially in families at risk (reduction of recurrence). The aim of this work was to examine the influence of thiamine (vitamin B1) on CL/P appearance in genetically determined A/WySn mice within different supplementation starting points. MATERIALS AND METHODS: A total of 24 A/WySn female mice were orally supplemented with high doses (80 mg/kg) of thiamine at different times of pregnancy (5 groups, n = 90). The influence of thiamine on the abortion rate and CL/P appearance in the offspring was analyzed with respect to the concentration of thiamine in the serum and amniotic fluid (HPLC-chromatography). Immunochemical analyses of the ThTr-1 und ThTr-2 receptor-status were performed in midface sections of A/WySn-fetuses and the corresponding placenta, with and without CL/P. RESULTS: High doses of orally supplemented thiamine did not reduce the CL/P appearance in A/WySn mice. However, the different starting points of vitamin B1 substitution had some influence. Additionally, an obvious decrease in aborted fetuses was noticed in all supplemented groups. The oral substitution caused a clear increase of the serum concentration in all mothers, but showed no increase of the amniotic fluid concentration. Then immunohistochemistry detected an overexpression of ThTr-1 in the midface and an irregular localization of ThTr-2 in the placenta of fetuses with clefts. CONCLUSION: Our results suggest a time-dependent influence of thiamine on CL/P appearance in female mice. The prophylactic/periconceptional, but not the therapeutic supplementation, starting point can be proposed as a crucial step for regular facial and palatal fusion in embryonic development. The absolute rate of CL/P was not reduced, and the concentration of the water-soluble thiamine could not increase in the amniotic fluid. Thus the proposed local effect of thiamine failed in the development of genetically determined mice.


Asunto(s)
Labio Leporino/genética , Labio Leporino/prevención & control , Fisura del Paladar/genética , Fisura del Paladar/prevención & control , Suplementos Dietéticos , Tiamina/administración & dosificación , Administración Oral , Animales , Labio Leporino/embriología , Fisura del Paladar/embriología , Femenino , Ratones , Embarazo , Insuficiencia del Tratamiento
5.
J Neurosurg ; 127(6): 1376-1383, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28298021

RESUMEN

OBJECTIVE In clinical routines, neuroprotective strategies in neurosurgical interventions are still missing. A pilot study (n = 30) and an analogously performed Phase III trial (n = 112) pointed to a beneficial effect of prophylactic nimodipine and hydroxyethyl starch (HES) in vestibular schwannoma (VS) surgery. Considering the small sample size, the data from both studies were pooled. METHODS The patients in both investigator-initiated studies were assigned to 2 groups. The treatment group (n = 70) received parenteral nimodipine (1-2 mg/hour) and HES (hematocrit 30%-35%) from the day before surgery until the 7th postoperative day. The control group (n = 72) was not treated prophylactically. Facial and cochlear nerve functions were documented preoperatively, during the inpatient care, and 1 year after surgery. RESULTS Pooled raw data were analyzed retrospectively. Intent-to-treat analysis revealed a significantly lower risk for hearing loss (Class D) 12 months after surgery in the treatment group compared with the control group (OR 0.46, 95% CI 0.22-0.97; p = 0.04). After exclusion of patients with preoperative Class D hearing, this effect was more pronounced (OR 0.38, 95% CI 0.17-0.83; p = 0.016). Logistic regression analysis adjusted for tumor size showed a 4 times lower risk for hearing loss in the treatment group compared with the control group (OR 0.25, 95% CI 0.09-0.63; p = 0.003). Facial nerve function was not significantly improved with treatment. Apart from dose-dependent hypotension (p < 0.001), the study medication was well tolerated. CONCLUSIONS Prophylactic nimodipine is safe and may be recommended in VS surgery to preserve hearing. Prophylactic neuroprotective treatment in surgeries in which nerves are at risk seems to be a novel and promising concept. Clinical trial registration no.: DRKS 00000328 ( https://drks-neu.uniklinik-freiburg.de/drks_web/ ).


Asunto(s)
Pérdida Auditiva/cirugía , Neuroma Acústico/cirugía , Fármacos Neuroprotectores/uso terapéutico , Procedimientos Neuroquirúrgicos/métodos , Nimodipina/uso terapéutico , Adulto , Femenino , Audición , Pérdida Auditiva/tratamiento farmacológico , Pérdida Auditiva/etiología , Pruebas Auditivas , Humanos , Masculino , Persona de Mediana Edad , Neuroma Acústico/complicaciones , Neuroma Acústico/tratamiento farmacológico , Proyectos Piloto , Estudios Retrospectivos , Resultado del Tratamiento
6.
J Neurosurg ; 124(3): 657-64, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26274985

RESUMEN

OBJECTIVE: A pilot study of prophylactic nimodipine and hydroxyethyl starch treatment showed a beneficial effect on facial and cochlear nerve preservation following vestibular schwannoma (VS) surgery. A prospective Phase III trial was undertaken to confirm these results. METHODS: An open-label, 2-arm, randomized parallel group and multicenter Phase III trial with blinded expert review was performed and included 112 patients who underwent VS surgery between January 2010 and February 2013 at 7 departments of neurosurgery to investigate the efficacy and safety of the prophylaxis. The surgery was performed after the patients were randomly assigned to one of 2 groups using online randomization. The treatment group (n = 56) received parenteral nimodipine (1-2 mg/hr) and hydroxyethyl starch (hematocrit 30%-35%) from the day before surgery until the 7th postoperative day. The control group (n = 56) was not treated prophylactically. RESULTS: Intent-to-treat analysis showed no statistically significant effects of the treatment on either preservation of facial nerve function (35 [67.3%] of 52 [treatment group] compared with 34 [72.3%] of 47 [control group]) (p = 0.745) or hearing preservation (11 [23.4%] of 47 [treatment group] compared with 15 [31.2%] of 48 [control group]) (p = 0.530) 12 months after surgery. Since tumor sizes were significantly larger in the treatment group than in the control group, logistic regression analysis was required. The risk for deterioration of facial nerve function was adjusted nearly the same in both groups (OR 1.07 [95% CI 0.34-3.43], p = 0.91). In contrast, the risk for postoperative hearing loss was adjusted 2 times lower in the treatment group compared with the control group (OR 0.49 [95% CI 0.18-1.30], p = 0.15). Apart from dose-dependent hypotension (p < 0.001), no clinically relevant adverse reactions were observed. CONCLUSIONS: There were no statistically significant effects of the treatment. Despite the width of the confidence intervals, the odds ratios may suggest but do not prove a clinically relevant effect of the safe study medication on the preservation of cochlear nerve function after VS surgery. Further study is needed before prophylactic nimodipine can be recommended in VS surgery.


Asunto(s)
Traumatismos del Nervio Craneal/prevención & control , Neuroma Acústico/cirugía , Nimodipina/uso terapéutico , Complicaciones Posoperatorias , Vasodilatadores/uso terapéutico , Adulto , Nervio Coclear/fisiopatología , Traumatismos del Nervio Craneal/etiología , Nervio Facial/fisiopatología , Femenino , Humanos , Masculino , Persona de Mediana Edad
8.
J Neurol Surg A Cent Eur Neurosurg ; 75(4): 251-8, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24114058

RESUMEN

UNLABELLED: BACKGROUND AND STUDY AIMS/OBJECT: Oral nimodipine improves neurologic outcome after aneurysmal subarachnoid hemorrhage. In addition, the neuroprotective efficacy of nimodipine has been revealed following skull base, laryngeal, and maxillofacial surgery. Pharmacokinetic investigations showed nimodipine to reach higher serum levels following parenteral versus enteral administration. Furthermore, a correlation between nimodipine levels in serum, cerebrospinal fluid, and nerve tissue could be quantified. These observations raise the question whether the proven neuroprotective effect of nimodipine is related to its serum level. PATIENTS/MATERIAL AND METHODS: A consecutive series of 37 patients with vestibular schwannoma treated with nimodipine from the day before surgery until the seventh postoperative day was analyzed retrospectively. Both groups received standard dosages for enteral (n = 17) and parenteral (n = 20) nimodipine medication. Nimodipine levels were measured in pre- and postoperative serum and cerebrospinal fluid samples. Cochlear and facial nerve functions were documented before surgery, in the early postoperative course, and 1 year after surgery. RESULTS: Facial nerve outcome was significantly better in the group with parenteral nimodipine medication (p = 0.038). Logistical regression analysis revealed a seven times smaller risk for a deterioration of facial nerve function in the group with parenteral treatment. There was no difference in hearing preservation between both groups despite tumor size tending to be larger in the parenteral group. Intraoperative (p = 0.004), postoperative (p = 0.001), and serum and cerebrospinal fluid (p = 0.024) nimodipine levels were significantly higher following parenteral administration as compared with enteral administration. Both groups were comparable regarding tumor size and extent of resection. CONCLUSIONS: These results support a dependency of nimodipine's neuroprotective efficacy on its serum levels. Parenteral nimodipine treatment produces higher serum levels and has a higher neuroprotective potency in vestibular schwannoma surgery compared with enteral treatment.


Asunto(s)
Nervio Coclear/efectos de los fármacos , Nervio Facial/efectos de los fármacos , Neuroma Acústico/cirugía , Fármacos Neuroprotectores/uso terapéutico , Nimodipina/uso terapéutico , Complicaciones Posoperatorias/prevención & control , Adulto , Anciano , Anciano de 80 o más Años , Nervio Coclear/fisiología , Nervio Facial/fisiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Fármacos Neuroprotectores/administración & dosificación , Fármacos Neuroprotectores/farmacocinética , Nimodipina/administración & dosificación , Nimodipina/farmacocinética , Complicaciones Posoperatorias/tratamiento farmacológico , Estudios Retrospectivos , Resultado del Tratamiento , Adulto Joven
9.
J Neurol Surg A Cent Eur Neurosurg ; 75(2): 84-90, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23504671

RESUMEN

UNLABELLED: BACKGROUND AND STUDY AIMS/OBJECT: Oral nimodipine is recommended to reduce poor outcome related to aneurysmal subarachnoid hemorrhage (SAH). In addition, animal experiments and clinical trails revealed a beneficial effect of enteral and parenteral nimodipine for the regeneration of cranial nerves following skull base, laryngeal, and maxillofacial surgery. Despite these findings there is a lack of pharmacokinetic data in the literature, especially concerning its distribution in nerve tissue. PATIENTS/MATERIAL AND METHODS: Samples were taken from a consecutive series of 57 patients suffering from skull base lesions and treated with nimodipine prophylaxis from the day before surgery until the seventh postoperative day. Both groups received standard dosages for enteral (n = 25) and parenteral (n = 32) nimodipine . Nimodipine levels were measured in serum, cerebrospinal fluid (CSF), and tissue samples, including vestibular nerves. RESULTS: Nimodipine levels were significantly higher following parenteral as compared with enteral administration for intraoperative serum (p < 0.001), intraoperative CSF (p < 0.001), tumor tissues (p = 0.01), and postoperative serum (p < 0.001). In addition, nimodipine was significantly more frequently detected in nerve tissue following parenteral administration (Fisher's exact test, p = 0.015). CONCLUSIONS: From a pharmacokinetic point of view, parenteral nimodipine medication leads to higher levels in serum and CSF. Furthermore, traces are more frequently found in nerve tissue following parenteral as compared with enteral nimodipine administration, at least in the early course.


Asunto(s)
Bloqueadores de los Canales de Calcio/administración & dosificación , Bloqueadores de los Canales de Calcio/farmacocinética , Nimodipina/administración & dosificación , Nimodipina/farmacocinética , Vasodilatadores/administración & dosificación , Vasodilatadores/farmacocinética , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Base del Cráneo/cirugía , Resultado del Tratamiento , Adulto Joven
10.
Neurosurgery ; 61(1): 92-7; discussion 97-8, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17621023

RESUMEN

OBJECTIVE: Facial nerve paresis and hearing loss are common complications after vestibular schwannoma surgery. Experiments with facial nerves of the rat and retrospectively analyzed clinical studies showed a beneficial effect of vasoactive treatment on the preservation of facial and cochlear nerve functions. This prospective and open-label randomized pilot study is the first study of a prophylactic vasoactive treatment in vestibular schwannoma surgery. METHODS: Thirty patients were randomized before surgery. One group (n = 14) received a vasoactive prophylaxis consisting of nimodipine and hydroxyethylstarch which was started the day before surgery and was continued until the seventh postoperative day. The other group (n = 16) did not receive preoperative medication. Intraoperative monitoring, including acoustic evoked potentials and continuous facial electromyelograms, was applied to all patients. However, when electrophysiological signs of a deterioration of facial or cochlear nerve function were detected in the group of patients without medication, vasoactive treatment was started immediately. Cochlear and facial nerve function were documented preoperatively, during the first 7 days postoperatively, and again after long-term observation. RESULTS: Despite the limited number of patients, our results were significant using the Fisher's exact test (small no. of patients) for a better outcome after vestibular schwannoma surgery for both hearing (P = 0.041) and facial nerve (P = 0.045) preservation in the group of patients who received a prophylactic vasoactive treatment. CONCLUSION: Prophylactic vasoactive treatment consisting of nimodipine and hydroxyethylstarch shows significantly better results concerning preservation of the facial and cochlear nerve function in vestibular schwannoma surgery. The prophylactic use is also superior to intraoperative vasoactive treatment.


Asunto(s)
Enfermedades del Nervio Facial/etiología , Enfermedades del Nervio Facial/prevención & control , Procedimientos Neuroquirúrgicos/efectos adversos , Nimodipina/administración & dosificación , Enfermedades del Nervio Vestibulococlear/etiología , Enfermedades del Nervio Vestibulococlear/prevención & control , Adolescente , Adulto , Anciano , Quimioterapia Adyuvante/métodos , Neoplasias de los Nervios Craneales/cirugía , Humanos , Masculino , Persona de Mediana Edad , Neurilemoma/cirugía , Proyectos Piloto , Resultado del Tratamiento , Vasodilatadores/administración & dosificación , Enfermedades del Nervio Vestibulococlear/cirugía
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