Dataset Information

Kappa-Opioid Receptor Blockade Ameliorates Obesity Caused by Estrogen Withdrawal via Promotion of Energy Expenditure through mTOR Pathway.

ABSTRACT: Weight gain is a hallmark of decreased estradiol (E2) levels because of menopause or following surgical ovariectomy (OVX) at younger ages. Of note, this weight gain tends to be around the abdomen, which is frequently associated with impaired metabolic homeostasis and greater cardiovascular risk in both rodents and humans. However, the molecular underpinnings and the neuronal basis for these effects remain to be elucidated. The aim of this study is to elucidate whether the kappa-opioid receptor (k-OR) system is involved in mediating body weight changes associated with E2 withdrawal. Here, we document that body weight gain induced by OVX occurs, at least partially, in a k-OR dependent manner, by modulation of energy expenditure independently of food intake as assessed in Oprk1-/-global KO mice. These effects were also observed following central pharmacological blockade of the k-OR system using the k-OR-selective antagonist PF-04455242 in wild type mice, in which we also observed a decrease in OVX-induced weight gain associated with increased UCP1 positive immunostaining in brown adipose tissue (BAT) and browning of white adipose tissue (WAT). Remarkably, the hypothalamic mTOR pathway plays an important role in regulating weight gain and adiposity in OVX mice. These findings will help to define new therapies to manage metabolic disorders associated with low/null E2 levels based on the modulation of central k-OR signaling.

SUBMITTER: Romero-Pico A

PROVIDER: S-EPMC8953356 | biostudies-literature | 2022 Mar

REPOSITORIES: biostudies-literature

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Kappa-Opioid Receptor Blockade Ameliorates Obesity Caused by Estrogen Withdrawal via Promotion of Energy Expenditure through mTOR Pathway.

Romero-Picó Amparo A Novelle Marta G MG Al-Massadi Omar O Beiroa Daniel D Tojo Marta M Heras Violeta V Ruiz-Pino Francisco F Senra Ana A López Miguel M Blouet Clemence C Tena-Sempere Manuel M Nogueiras Rubén R Diéguez Carlos C

International journal of molecular sciences 20220314 6

Weight gain is a hallmark of decreased estradiol (E2) levels because of menopause or following surgical ovariectomy (OVX) at younger ages. Of note, this weight gain tends to be around the abdomen, which is frequently associated with impaired metabolic homeostasis and greater cardiovascular risk in both rodents and humans. However, the molecular underpinnings and the neuronal basis for these effects remain to be elucidated. The aim of this study is to elucidate whether the kappa-opioid receptor ( ...[more]

PMID: 35328539

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Dataset Information

Kappa-Opioid Receptor Blockade Ameliorates Obesity Caused by Estrogen Withdrawal via Promotion of Energy Expenditure through mTOR Pathway.

Publications

Kappa-Opioid Receptor Blockade Ameliorates Obesity Caused by Estrogen Withdrawal via Promotion of Energy Expenditure through mTOR Pathway.

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