Leptin Action in Pubertal Development

<p>Previous illnesses (A)</p> Signup and view all the answers

<p>Increased activity of the hypothalamic–pituitary–gonadal (HPG) axis (A)</p> Signup and view all the answers

<p>They are reactivated at the onset of puberty, leading to increased GnRH release. (A)</p> Signup and view all the answers

<p>It becomes more frequent and occurs in pulses. (A)</p> Signup and view all the answers

<p>It provided insights into the role of the HPG axis in controlling reproduction. (B)</p> Signup and view all the answers

<p>Body size (A)</p> Signup and view all the answers

<p>A critical amount of body fat is required for proper pubertal development. (B)</p> Signup and view all the answers

<p>Puberty onset is consistently occurring at earlier ages. (B)</p> Signup and view all the answers

<p>Tanner stage 2 of breast development (A)</p> Signup and view all the answers

<p>5-8% (B)</p> Signup and view all the answers

<p>Obesity is linked to earlier puberty onset. (C)</p> Signup and view all the answers

<p>Leptin (A)</p> Signup and view all the answers

<p>Adipocytes (D)</p> Signup and view all the answers

<p>Class I cytokine-receptor (C)</p> Signup and view all the answers

<p>JAK/STAT pathway (C)</p> Signup and view all the answers

<p>Leptin receptor long form (C)</p> Signup and view all the answers

<p>Obesity, diabetes, and infertility (C)</p> Signup and view all the answers

<p>Neuron-specific deletion of STAT3 (C)</p> Signup and view all the answers

<p>Fertile (C)</p> Signup and view all the answers

<p>db/db mice (C)</p> Signup and view all the answers

<p>Mediating reproduction signals (D)</p> Signup and view all the answers

<p>It acts as a metabolic signal influencing reproductive functions. (C)</p> Signup and view all the answers

<p>Ventral premammillary nucleus (D)</p> Signup and view all the answers

<p>Rescue from sterility (B)</p> Signup and view all the answers

<p>It reduces kisspeptin expression. (D)</p> Signup and view all the answers

<p>It's not critical for female reproductive maturation. (C)</p> Signup and view all the answers

<p>Missense mutation (C)</p> Signup and view all the answers

<p>Androgen and estrogen receptor mRNA (D)</p> Signup and view all the answers

<p>Kiss1 neurons (C)</p> Signup and view all the answers

<p>Hyperphagia and decreased energy expenditure (B)</p> Signup and view all the answers

<p>They develop normally, but remain in a prepubertal state (A)</p> Signup and view all the answers

<p>Leptin administration (C)</p> Signup and view all the answers

<p>It decreases their body weight (B)</p> Signup and view all the answers

<p>It decreases gonadotropin levels (C)</p> Signup and view all the answers

<p>Leptin increases the pulsatile rate of GnRH secretion (B)</p> Signup and view all the answers

<p>Sex steroid levels are reduced (A)</p> Signup and view all the answers

<p>It is not required for pubertal development (C)</p> Signup and view all the answers

<p>It disrupts the HPG axis at puberty. (C)</p> Signup and view all the answers

<p>Leptin's effects are dependent on the PI3K signaling pathway. (C)</p> Signup and view all the answers

<p>Glutamate signaling stimulates GnRH neurons at puberty. (C)</p> Signup and view all the answers

<p>Phosphatidylinositol 3-kinase (PI3K) signaling pathway. (C)</p> Signup and view all the answers

<p>Central metabolic imbalances. (B)</p> Signup and view all the answers

<p>Kisspeptin activates GnRH neurons as a neuroendocrine switch for puberty onset. (C)</p> Signup and view all the answers

<p>Kinesin superfamily-associated protein 3. (B)</p> Signup and view all the answers

<p>Estrogen receptor alpha signaling in kisspeptin neurons. (A)</p> Signup and view all the answers

The start of the menstrual cycle in females, marking the beginning of puberty.

A process of physical changes that leads to sexual maturity.

A group of hormones that play a key role in controlling the reproductive system.

A network of glands in the brain and body that controls the production and release of hormones, particularly those related to reproduction.

A hormone released from the hypothalamus that triggers the release of gonadotropins from the pituitary gland.

The part of the brain that plays a crucial role in controlling the HPG axis and the timing of puberty.

The gland in the brain that releases gonadotropins in response to GnRH from the hypothalamus.

A chemical messenger in the body that helps regulate various functions and processes.

The onset of puberty is triggered when a certain threshold of body fat is reached, irrespective of chronological age.

Studies in the past two decades have consistently reported a trend of earlier puberty onset in girls.

The initial stages of breast development (Tanner stage 2) are used as the clinical indicator for puberty onset.

Obesity has been linked to an earlier appearance of clinical signs of puberty onset in girls compared to non-obese girls.

Leptin, a hormone produced by fat cells, plays a crucial role in regulating pubertal development and is considered a key permissive factor.

Mice deficient in leptin, a hormone vital for regulating pubertal development, exhibit reproductive deficits.

The onset of puberty is intricately regulated by a complex interplay of various factors, including metabolic cues and the developmental stage.

The presence of redundant neural pathways and metabolic cues highlights the robust and complex nature of pubertal regulation.

A member of the class I cytokine-receptor family that activates the JAK/STAT signaling pathway.

A signaling pathway involved in regulating various cellular processes, including cell growth, differentiation, and survival.

A protein within the leptin receptor that is crucial for STAT3 activation.

The isoform of the leptin receptor that contains the Box 3 motif and is responsible for the primary signaling function.

A type of STAT protein that plays a crucial role in leptin signaling.

A mutation that leads to the absence of the leptin receptor long form.

Mice with a neuron-specific deletion of STAT3.

Mice with a mutation that disrupts STAT3 signaling specifically through the leptin receptor.

A genetic model of obesity due to a deficiency in leptin, a hormone involved in appetite regulation. These mice are characterized by excessive eating (hyperphagia) and reduced energy expenditure, resulting in significant weight gain.

A condition characterized by early onset obesity due to a deficiency in leptin, resulting in severely overweight individuals.

A potent hormone involved in appetite regulation, energy expenditure, and reproductive processes. It is primarily produced by adipose tissue (fat cells) and acts on specific receptors in the brain and other tissues.

The long form of the leptin receptor, responsible for mediating the biological effects of leptin throughout the body. It is primarily found in the brain, where it plays a critical role in regulating appetite and metabolism.

The primary site of action for leptin, where it regulates energy balance and reproductive functions. It acts by binding to the long form of the leptin receptor, initiating biochemical responses.

A condition caused by a deficiency in leptin, leading to obesity, infertility, and other metabolic problems.

A type of neuron in the hypothalamus that is sensitive to leptin levels.

A brain region involved in regulating various functions, including reproduction, appetite, and stress response. It plays a key role in the response to leptin.

A family of peptides that play a crucial role in regulating the release of GnRH and the timing of puberty.

A neurotransmitter that plays a role in regulating pubertal development. It plays a crucial role in mediating excitatory control of female puberty.

This signaling pathway is crucial in the brain and is involved in responses to leptin. It plays a role in regulating the timing of puberty.

A complex system that controls the production and release of hormones essential for reproduction. It is the main regulatory network for puberty.

A hormone released from the hypothalamus that stimulates the release of gonadotropins from the pituitary gland.

A specific type of neuron that plays a critical role in the onset of puberty. These neurons receive signals from leptin and other cues that influence pubertal timing.

A complex pattern of physical changes that leads to sexual maturity. It is influenced by various factors including hormones, genetics, and environmental cues.