Solid-Phase Peptide Synthesis

Anorexia nervosa, otherwise stated as anorexia, is an eating disorder that occurs when an individual restricts themselves from necessary energy intake which leads to significantly low body weight. Other characteristics of this disorder include: intense fear of becoming fat or gaining weight, persistent behavior that interferes with weight gain, and disturbances of perception and experience of their own body weight and shape (DSM V, 2013). Effective treatments are still trying to be researched for this disorder, as there is not a “one size fits all” for people of all age groups, living situations, etc. Since adolescents with anorexia are such a vulnerable population,

Bailer et al (1970) compared serotonin activity in recovering anorexia suffers and healthy controls. They found significantly higher activity in the women that were recovering from anorexia, the highest levels found in those women with the highest anxiety levels. This also provides support for AN having a biological cause, in this case an imbalance of neurotransmitters.

Ghrelin, commonly referred to as the “hunger hormone,” is a 28-amino acid peptide that has many important roles in human digestion including regulation of growth hormone release, enhancement of appetite, and increase of food intake (1). This gut-derived peptide could play an extremely important role in the altered eating behaviors of patients with eating disorders. Increased fasting plasma ghrelin levels have been consistently reported in underweight patients with anorexia nervosa. Circulating levels of this hormone have also been found to be enhanced in symptomatic bulimic patients, while also being blunted in response to balanced meals (4).

Leptin is released through the arcuate nucleus and leptin helps to check the fat content of the body. If there is not enough fat, then our body gets the signal to be hungry and eat something. There are two types of appetite control neuron in the arcuate nucleus. They are NPY neurons and POMC neurons. NPY neurons can stimulate the appetite and reduce metabolism (Ceballos 2016). When the leptin level is high, this reducing metabolism process can be inhibited. These neurons can work as hunger neurons that can be stimulated by ghrelin. This peptide hormone is made by and released by the gut to increase appetite. During fasting, high concentration of ghrelin can strongly stimulate appetite and decrease suddenly when you eat something. NPY neurons inhibited by PYY3-36 to decrease appetite. PYY3-36 is released by intestinal cells. This small peptide level is increased after a meal to lower the appetite (satiety) signal (Ceballos 2016). This PYY3-36 acts on hypothalamic appetite control mechanism. PYY3-36 is very low in obese people, causing them to feel hungry and gain weight. The other type of appetite control neurons in arcuate nucleus is POMC neurons. These neurons can lower or inhibit appetite and increase the metabolism. They are also useful in acting as satiety

Some types of medications may help reduce symptoms of binge eating disorder, but are not designed

The three nationally recognized eating disorders are identified as Bulimia Nervosa, Anorexia Nervosa, and Binge-Eating Disorder. Eating disorders, although stereotypically viewed as a lifestyle choice, is a serious and often fatal illness that not only cause severe eating disturbances, but adverse psychological and physiological environments for the individual (National Institute of Mental Health, 2006). These disorders typically develop in the mid-to-late teen years and often carry out into early adulthood albeit also existing in late adulthood (Butcher, Mineka, & Hooley, 2004). Treatment for this class of disorder can range from various perspectives, current methodologies for binge-eating disorder point to cognitive therapies and pharmacotherapy (Reas & Grilo, 2014).

Tryptophan is a large neutral amino acid present in living organisms, which is precisely one of the twenty L-amino acids incorporated in proteins and one of the nine essential amino acids which cannot be endogenously synthesised and needs to be supplied with ailments. It is a precursor for various neurotransmitters such as serotonin, which is essential for maintaining mood balance and the regulation of appetite. It is also regarded that a deficit of the neurotransmitter may lead to depression and other mood disorders. With that being said, intake of serotonin precursors is essential for the amount of serotonin in the brain.

Over time, many diseases and famines have spread across the globe. In the modern, developed world, different, yet equally severe, problems have arisen. One of the leading complications in today’s society is eating disorders. These relentless disturbances are known for being lethal and for ravaging the world.

In our Western society, we have several different types of eating dysfunction, all of which are unique and tragic in their own right. Despite their individuality, however, they all have several overlapping symptoms that are key to their classification and severity. For Bulimia Nervosa (BN) and Binge Eating Disorder (BED), one of the core features is binge eating, which can be defined objectively by number of calories eaten in a given time or subjectively by the feelings of the binger. Binge eating has many different aspects that are of interest to scientists and clinicians alike. One of those interests has to do with the reduction of this symptom among populations being treated for their respective disorder. Because both

This system is comprised of Pro-opiomelanocortin (POMC) and AgRP neurons of the arcuate hypothalamus (Arc), neuropeptides α-MSH and AgRP, and central melanocortin receptors (MCRs) MC3R and MC4R. POMC and AgRP neurons monitor energy state and change their activity to alter feeding and body weight. When energy needs are met, POMC neurons release α-MSH which acts as an agonist on MC3R and MC4R. AgRP is released in response to an energy deficit and acts as an inverse agonist/antagonist of the central MCRs. Activation of POMC and AgRP neuron signaling has an opposite effect on feeding behavior such that the stimulation of POMC neurons or injection of MCR agonist decreases food intake and body weight27-29 , whereas AgRP neuron activation, central administration or overexpression of AgRP stimulates food intake and weight gain27,30-33. In addition to neuropeptide-mediated signaling, both POMC and AgRP neurons are also capable of fast neurotransmission via Glutamate and/or GABA34-36 and this neurotransmission has been suggested to play an important role in the ability of POMC and AgRP neurons to control feeding27,32. Although much is known about the role of AgRP and POMC neurons in the regulation of feeding and body weight, there is still much to be learned about the larger role these neurons play in energy homeostasis, including their interactions with non-homeostatic circuits, and a better understanding of the role GABA and Glutamate released from POMC and AgRP neurons play in feeding

Serotonin (5-hydroxytryptamine, 5-HT) is a neurotransmitter in the brain that has an enormous influence over many brain functions. It is synthesized, from the amino acid L-tryptophan, in brain neurons and stored in vesicles. Serotonin is found in three main areas of the body: the intestinal wall; large constricted blood vessels; and the central nervous system. The most widely studied effects have been those on the central nervous system. The functions of serotonin are numerous and appear to involve control of appetite, sleep, memory and learning, temperature regulation, mood, behavior (including sexual and hallucinogenic behavior), cardiovascular function, muscle contraction, endocrine regulation, and

Ghrelin is the first hormone to be identified that increases feeding when administered peripherally. All of the other known orexigenic peptide transmitters such as neuropeptide Y, orexin, agoutirelated peptide (AGRP), melanocortin-concentrating hormone, and galanin stimulate feeding only when administered into the brain. The observations that circulating ghrelin levels surge suddenly before a meal and fall sharply after a meal, suggest that ghrelin serves as a signal for initiation of feeding. Interestingly, ghrelin increases the number but not the size of meals. However, ghrelin does not only play a role in regulating short-term feeding, but it also regulates body weight over the long-term (Cummings et al.,

Overeating provides an interesting parallel to addictive behaviour. Much like habitual drug users, obese individuals commonly report experiencing craving and preoccupation with food (Herman and Polivy, 2008; Jastreboff, Sinha, Lacadie, Small, Sherwin & Potenza, 2013). The influence that food relevant cues (e.g. sight, smell, taste) have on food intake has also been well documented (for review see Herman & Polivy, 2008). It is plausible that dopaminergic conditioning

     The process of Protein Synthesis involves many parts of the cell. Unlike other similar productions, this process is very complex and precise and therefore must be done in proper sequence to work effectively. The slightest error during this process could cause the action to experience difficulty or even fail. For example, in the production of starch, glucose molecules are combined to be stored and eventually utilized as usable chemical energy. The cell can break down the starch with little difficulty as if each molecule was identical, even though there is a wide variety of molecules. This is a different case in Protein Synthesis. In Protein Synthesis, there are

Pleasure eating is the habit of enjoying tantalizing food and longingly looking forward to the next meal. Pleasure food is often produced by adding salt, fat, or sugar to captivate people and ensure they crave for it. Foods have a powerful effect not only because they nourish and make people healthy but because they make individuals emotionally happy. The pleasure that food gives is a powerful sensation that could easily become addictive. The fulfillment of the human and natural instinct is often pleasing and leads to subsequent consummation. In this regard, pleasure eating aims correlates to the two fundamental requirements of life, which ate sustenance and replication.