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1.
Hum Reprod ; 39(3): 578-585, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38268234

RESUMEN

STUDY QUESTION: What is the temporal activity and the concentration in follicular fluid (FF) of the anti-inflammatory steroid cortisol during the ovulatory process in humans? SUMMARY ANSWER: Intrafollicular concentrations of cortisol become massively upregulated close to ovulation concomitant with an exceptionally high biological activity securing a timely and efficient termination of inflammatory processes. WHAT IS KNOWN ALREADY: Ovulation has been described as a local, controlled inflammatory process resulting in the degeneration of the follicle wall which facilitate oocyte extrusion. Ovulation also affects the glucocorticoid metabolism of granulosa cells (GCs) and although de novo synthesis of cortisol only occurs in the adrenal cortex, the mid-cycle surge has been shown to induce a change from high expression of HSD11B2, inactivating cortisol to cortisone, to high expression of HSD11B1 which reversibly catalyses cortisol production from cortisone. Furthermore, high concentrations of progesterone and 17OH-progesterone within follicles may cause dislodging of cortisol from cortisol binding protein (CBP) thereby activating the biological activity of cortisol. STUDY DESIGN, SIZE, DURATION: This prospective cohort study included 50 women undergoing fertility treatment according to a standard antagonist protocol at a university hospital-affiliated fertility clinic in Denmark. PARTICIPANTS/MATERIALS, SETTING, METHODS: Women donated FF and GCs from one follicle for research purpose aspirated at one of four time points during the process of final maturation of follicles: T = 0 h, T = 12 h, T = 17 h, T = 32 h. A second sample was collected at oocyte pick up at T = 36 h. The concentration of cortisol and cortisone together with a range of sex steroids was measured by LC-MS/MS in FF collected at the five time points mentioned above. Whole genome microarray data, validated by q-PCR analysis, was used to evaluate gene expression of CYP11B1, CYP21A2, HSD11B1, HSD11B2, and NR3C1 in GCs at the same time points. MAIN RESULTS AND THE ROLE OF CHANCE: The concentration of cortisol was significantly increased from a few nM at 0 h to around 100-140 nM (P ≤ 0.0001) at 32-36 h, whilst cortisone was almost constant from 0 to 17 h at a concentration of between 90 and 100 nM being significantly reduced to 25-40 nM (P ≤ 0.0001) at 32-36 h. This was paralleled by a 690-fold upregulation of HSD11B1 from 0 to 12 h increasing to a more than 20.000-fold change at 36 h. HSD11B2 was quickly downregulated 15- to 20-fold after ovulation induction. Concentrations of progesterone and 17OH-progesterone increased during the ovulatory process to high levels which in essence displaces cortisol from its binding protein CBP due to similar binding affinities. Furthermore, a significant decrease in 11-deoxycortisol expression was seen, but CYP11B1 expression was below detection limit in GCs. LIMITATIONS, REASONS FOR CAUTION: The study included women undergoing ovarian stimulation and results may differ from the natural cycle. More observations at each specific time point may have strengthened the conclusions. Furthermore, we have not been able to measure the actual active biological concentration of cortisol. WIDER IMPLICATIONS OF THE FINDINGS: For the first time, this study collectively evaluated the temporal pattern of cortisol and cortisone concentrations during human ovulation, rendering a physiological framework for understanding potential dysregulations in the inflammatory reaction of ovulation. STUDY FUNDING/COMPETING INTEREST(S): This research was supported by the University Hospital of Copenhagen, Rigshospitalet, and Novo Nordisk Foundation grant number NNF21OC00700556. Interreg V ÔKS through ReproUnion (www.reprounion.eu); Region Zealand Research Foundation. The funders had no role in study design, collection of data, analyses, writing of the article, or the decision to submit it for publication. The authors have no conflicts of interest to declare. TRIAL REGISTRATION NUMBER: N/A.


Asunto(s)
Cortisona , Progesterona , Femenino , Humanos , Progesterona/metabolismo , Hidrocortisona , Estudios Prospectivos , Esteroide 11-beta-Hidroxilasa , Cromatografía Liquida , Fertilización In Vitro/métodos , Espectrometría de Masas en Tándem , Ovulación , Inducción de la Ovulación/métodos , Esteroide 21-Hidroxilasa
2.
Reprod Biomed Online ; 49(2): 103853, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38865783

RESUMEN

RESEARCH QUESTION: How is the production of progesterone (P4) and 17-hydroxy-P4 (17-OH-P4) regulated between theca cells and granulosa cells during the follicular phase, during ovulation and after transformation into a corpus luteum? DESIGN: Three cohorts were examined: (i) 31 women undergoing natural and stimulated cycles, with serum hormone measurements taken every 3 days; (ii) 50 women undergoing ovarian stimulation, with hormone concentrations in serum and follicular fluid assessed at five time points during final follicle maturation; and (iii) 12 women undergoing fertility preservation, with hormone concentrations evaluated via the follicular fluid of small antral follicles. RESULTS: In the early follicular phase, theca cells primarily synthesized 17-OH-P4 while granulosa cells produced limited P4, maintaining the P4:17-OH-P4 ratio <1. As follicles reached follicle selection at a diameter of approximately 10 mm, P4 synthesis in granulosa cells was up-regulated, but P4 was mainly accumulated in follicular fluid. During final maturation, enhanced activity of the enzyme HSD3B2 in granulosa cells enhanced P4 production, with the P4:17-OH-P4 ratio increasing to >1. The concentration of 17-OH-P4 in the luteal phase was similar to that in the follicular phase, but P4 production increased in the luteal phase, yielding a P4:17-OH-P4 ratio significantly >1. CONCLUSIONS: The P4:17-OH-P4 ratio reflects the activity of granulosa cells and theca cells during the follicular phase and following luteinization in the corpus luteum. Managing the function of granulosa cells is key for reducing the concentration of P4 during ovarian stimulation, but the concerted action of FSH and LH on granulosa cells during the second half of the follicular phase makes this complex.


Asunto(s)
Líquido Folicular , Células de la Granulosa , Progesterona , Células Tecales , Femenino , Líquido Folicular/metabolismo , Humanos , Células de la Granulosa/metabolismo , Progesterona/biosíntesis , Progesterona/metabolismo , Células Tecales/metabolismo , Adulto , 17-alfa-Hidroxiprogesterona/metabolismo , 17-alfa-Hidroxiprogesterona/sangre , Folículo Ovárico/metabolismo
3.
Anaesth Rep ; 9(1): 114-117, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34099999

RESUMEN

Flexible bronchoscopic tracheal intubation is a fundamental technique in the management of the difficult airway but requires specific skills which may be both difficult to achieve and maintain. Therefore, techniques to improve its success should be developed. We present two cases, one where the ear, nose and throat surgeon could not view the glottis due to laryngeal pathology, and one where pathology in the oropharynx obscured access to the trachea during attempts at flexible bronchoscopic and videolaryngoscopic tracheal intubation. In both cases, tracheal intubation was subsequently successful due to the use of the Infrared Red Intubation System. This is an infrared light source that is secured to the anterior neck. It emits a flashing infrared light that is captured by the flexible bronchoscope, thus guiding the way to the trachea. These are the first reports of this technology being used for flexible bronchoscopic tracheal intubation in patients with severe airway pathology where conventional approaches had failed. Both cases emphasise that this technique can be of benefit in avoiding a surgical airway.

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