Background: Neurokinin B (NKB) is a member of the tachykinin family of peptides. Inactivating mutations in the tachykinin 3 or tachykinin 3 receptor gene are associated with pubertal failure and congenital hypogonadotrophic hypogonadism in humans. This suggests that NKB may have a critical role in human reproduction. The effects of NKB administration have not been investigated previously in humans.
Aim: The aim of this study was to determine the effects of iv administration of NKB on gonadotrophin secretion in healthy male and female volunteers.
Methods: A total of 23 healthy men and 11 healthy women participated in the study. After an initial dose-finding study (study 1), men received a 4-hour infusion of vehicle (gelofusin) followed by a 4-hour infusion of NKB (2.56 or 5.12 nmol/kg/h) (study 2), and an 8-hour infusion of vehicle or NKB during different visits (study 3). Healthy women underwent a dose-finding study consisting of a 3-hour NKB administration during the follicular phase of the menstrual cycle, and the maximum dose of NKB was also tested during the preovulatory and midluteal phases of menstrual cycle (study 4).
Results: Mean LH, FSH, and T secretion were not significantly altered during a 90-minute infusion of NKB (0.4-5.12 nmol/kg/h), or a 4-hour infusion of NKB (5.12 nmol/kg/h). No alterations in gonadotrophin secretion or LH pulsatility were observed during an 8-hour infusion of NKB when compared with vehicle. Doses of 0.64-5.12 nmol/kg/h NKB did not significantly alter LH, FSH, or estradiol secretion in healthy women during the follicular phase of the menstrual cycle. Finally, 5.12 nmol/kg/h did not significantly alter reproductive hormone secretion during the preovulatory or midluteal phases of the menstrual cycle.
Conclusions: This is the first clinical study of NKB administration. None of the doses of NKB tested were associated with significant alterations in reproductive hormone secretion in healthy male or female volunteers. These novel data add to our understanding of the physiological actions of NKB in human reproduction.
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http://dx.doi.org/10.1210/jc.2012-2880 | DOI Listing |
Mycobacterium tuberculosis (M.tb) infection can lead to various outcomes, including active tuberculosis or latent tuberculosis infection (LTBI). Household contacts of TB cases have a high risk of acquiring LTBI.
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December 2024
Department of Pathology, Stanford University School of Medicine, Stanford, United States.
The growth and survival of cells with different fitness, such as those with a proliferative advantage or a deleterious mutation, is controlled through cell competition. During development, cell competition enables healthy cells to eliminate less fit cells that could jeopardize tissue integrity, and facilitates the elimination of pre-malignant cells by healthy cells as a surveillance mechanism to prevent oncogenesis. Malignant cells also benefit from cell competition to promote their expansion.
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January 2025
Department of Nutritional Physiology, National Institute of Medical and Nutritional Sciences "Salvador Zubirán", Mexico City, Mexico.
Childhood obesity increases the risk of developing metabolic diseases in adulthood, since environmental stimuli during critical windows of development can impact on adult metabolic health. Studies demonstrating the effect of prepubertal diet on adult metabolic disease risk are still limited. We hypothesized that a prepubertal control diet (CD) protects the adult metabolic phenotype from diet-induced obesity (DIO), while a high-fat diet (HFD) would predispose to adult metabolic alterations.
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January 2025
CFD Research Corporation, Huntsville, AL, United States of America.
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Department of Orthopedics, Xiangyang Central Hospital, Affiliated Hospital of Hubei University of Arts and Science, Hubei, China.
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Method: The inverse variance weighted (IVW) approach to MR was primarily used to explore causal associations between exposures and outcomes using publicly available genetic variants from large genome-wide association studies (GWAS).
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