Neuropsychiatric disorder

Question 1

Neuropsychiatric disorders

Answer 1

Refers to several disorders encompassing a broad range of medical conditions involving both neurology and psychiatry and cognitive deficit disorders

Question 2

common neuropsychiatric disorders

Answer 2

-ADD
-anxiety
-schizophrenia (SZ)
-Bipolar disorder (BD)
-major depressive disorder (MDD)
ADHD

Question 3

Anxiety disorder characterisation

Answer 3

Persistent and excessive fear and anxiety and the dysfunctional behavioral changes a patient may use to mitigate these feelings

Question 4

How do anxiety disorders differ from one another

Answer 4

Based on specific objectives or situations that induce fear, anxiety and associated behavioural changes

Question 5

Anxiety triggers

Answer 5

Neurobiological responses
-Perpetration of violence
-Self-rewarding lust of violence/gaining power
-Appetitive aggression
-Reactive aggression
-PTSD
_Traumatic experiences
-Violent environment ( stressful life and trauma)

Question 6

stress response

Answer 6

Question 7

HPA axis

Answer 7

Stress triggers a freed-forward mechanism of the HPA axis by activating the hypothalamus to release corticotrophin-releasing hormone (CRH), which binds to the anterior pituatary gland and induces secretion of adrenocorticotrophic hormone (ACTH)

Question 8

ACTH effect

Answer 8

Triggers adrenal cortex to release glucocorticoids like cortisol, which binds to glucocorticoid receptors (GRs) to activate metabolic effects for survival during stressful event

Question 9

Cortisol role in HPA axis

Answer 9

It balances the freedforward and feedback mechanisms by deactivating both the hypothalamus and the pituatary gland
-Therefore, it is characterised by feeling less alert and having trouble focusing or doing everyday tasks including memory loss

Question 10

corisol homeostasis

Answer 10

Down regulation of the freed-forward mechanism of the HPA axis is crucial to ensuring the homeostasis of cortisol levels during stress
-disruption can lead to an imbalance between feedforward and feedback mechanisms, with elevated negative feedback thought to result in blunted cortisol due to desensitization, as well as the development of both PTSD and aggression

Question 11

What causes HPA axis dysfunction?

Answer 11

*Chronic stress can lead to HPA axis
dysfunction and cause consistently increased
cortisol levels in your body

Question 12

constantly increased cortisol effect

Answer 12

Mental health conditions, like mood
disorders, anxiety disorders,
depression and post-traumatic stress disorder
(PTSD)
*Metabolic diseases, such as
diabetes, obesity and cancer
*Cardiovascular diseases, like high blood
pressure and vascular damage
*HPA axis dysfunction may also play a role
in memory loss and neurodegenerative
conditions like Alzheimer’s disease

Question 13

HPA axis dysfunction

Answer 13

HPA axis dysfunction is a complex,
biochemical and physiological process
*Research scientists are still investigating and
studying its causes and health impacts

Question 14

serotonin

Answer 14

-Serotonin is best known as a
neurotransmitter that modulates neural
activity
-a wide range of
neuropsychological processes, and drugs that
target serotonin receptors are used widely in
psychiatry and neurology

Question 15

serotnin location

Answer 15

*Serotonin is abundantly found outside the
central nervous system
-its
15 receptors are all expressed peripherally
and within the brain

Question 16

serotonin role

Answer 16

*Serotonin regulates numerous biological
processes, including cardiovascular function,
bowel motility, ejaculatory latency, and
bladder control

Question 17

serotonin production cell type

Answer 17

Serotonin is almost exclusively produced in
neurons originating in the raphe nuclei
located in the midline of the brainstem
* These serotonin-producing neurons form the
largest and most complex efferent system in
the human brain

Question 18

location of raphae nuclei

Answer 18

The most caudal raphe innervates the spinal
cord, while the more rostral raphe, the dorsal
raphe nucleus and the medial raphe nucleus
innervate much of the rest of the CNS by
diffuse projections

Question 19

Trp in physiological conditions

Answer 19

Under physiological conditions, the majority
of Tryptophan (Trp) is degraded along the
kynurenine pathway (KP) and only about 1%
is metabolised into serotonin (5-HT)

Question 20

serotonin transformation + enzymes

Answer 20

This metabolic route begins with the
transformation of Trp into 5-hydroxytryptophan
and then into serotonin through two consecutive
reactions catalysed by the enzymes tryptophan
hydroxylase (TPH) and 5-hydroxytryptophan is a
decarboxylase (AADC= aromatic l amino acid decarboxylase)

Question 21

rate limiting enzme + function in serotonin production (melatonin transformation

Answer 21

the rate-limiting enzyme
arylalkylamine N-acetyltransferase (AANAT)
promotes the acetylation of serotonin into Nacetylserotonin (NAS), which, in turn, serves as a substrate for the hydroxy indole-O-methyl
transferase (HIOMT or acetylserotonin Omethyltransferase, ASMT) to generate melatonin

Question 22

Melatonin functions

Answer 22

Melatonin is an essential player in the
regulation of energy metabolism and glucose
homeostasis
*It is responsible for the daily distribution of
energy metabolism functions (daily phase of
high insulin sensitivity, glycogen synthesis,
and lipogenesis and a sleep phase associated
with the usage of stored energy)

Question 23

Low melatonin secretion effects

Answer 23

independently been associated with a higher
risk for type 2 diabetes (T2DM)

Question 24

AFMK

Answer 24

N-acetyl-N-formyl-5-
methoxykynurenamine (AFMK)

Question 25

AFMK production

Answer 25

-melatonin can be cleaved by indoleamine 2,3-
dioxygenase 1 (IDO1) in a nonspecific reaction
-melatonin can yield AFMK by directly
scavenging hydrogen peroxide or as a substrate of
neutrophils’ myeloperoxidase
NB antioxidant

Question 26

melatonin and hydogen peroxide reaction

Answer 26

, AFMK can arise from the reaction of
melatonin with hydroxyl radical and the subsequent
interaction of the new-born melatonyl species with
superoxide anion

Question 27

AFMK research

Answer 27

Research involving cell culture, AFMK
efficiently reduced hippocampal neuronal
death caused by either hydrogen peroxide or
amyloid b25-35 peptide

Question 28

AFMK significance

Answer 28

*AFMK is a naturally occurring molecule with
potent free radical scavenging capacity
(donating two electrons/molecule)
*It thus may be a valuable new antioxidant for
preventing and treating free radical-related
disorders

Question 29

genes associated with neuropsychiatric disorders

Answer 29

COMT
encoding for catechol-O-methyl transferase
(COMT), an enzyme that catalyses the
extraneuronal breakdown of catecholamines

Question 30

epigenetic factors associated with neuropsychiatric disorders

Answer 30

*Additional epigenetic changes found on these
genes, especially at their promoter regions,
influence the disease
*A number of cytosine-guanine methylation have
been found and have been associated with
neuropsychiatric disorders