Definition and functions of various biological terms


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Avonex is the brand name of Interferon-β, the therapeutic use of this medication is to help patient's chronic inflammatory demyelinating disease known as multiple sclerosis (MS). Multiple sclerosis is a chronic inflammatory demyelinating disease of a central nervous system disease where people face repeated autoimmune attacks at the early stages. Interferon- β delays disability sequence and reduces the relapsing of MS and it does so by applying its complex effects by bringing about a collection of both genetic and metabolic processes. Interferon beta decrease the production of both T lymphocytes and proinflammatory cytokines, thereby altering the cytokine response to more favourable inflammatory Th2 type response as oppose to Th1. Th2 cells synthesise IL-4 and IL-10 cytokines which stimulate an increase in B cells which then mature in the plasma cells producing antibodies. Th2 also inhibits the function of Th1 cells e.g. inactivates the inflammatory cells and cell mediated reaction carried out by Th1 cytokines. Avonex also inhibits the migration of inflammatory cells and T-lymphocytes to central nervous system. Recent research concludes that Th17 cells have an important part in the advancements of autoimmune responses in MS. 1,2

Zyloric is the brand name of allopurinol. Allopurinol reduces the concentration of the relative insoluble urates and uric acid in tissues, plasma and urine, while increasing the concentration of their more soluble precursors, the xanthine and hypoxanthines. The deposition of urates crystals in tissues is revered, and the formation of renal stones is inhibited. Allopurinol is the drug of choice in the long-term treatment of gout, but it is ineffective in the treatment of an acute attack and may even exacerbate the inflammation.3

Allopurinol is very effective drug to be used with patients with gout but only for long term treatment as short term use of the medicine involves worsening of inflammation. Allopurinol is used to minimise the synthesis of uric acid by competitive inhibition of xanthine oxidase. Alloxanthine oxidase is converted from allopurinol and so this metabolite acts as a non-competitive inhibitor of the enzyme and can also remain unchanged in the tissue for some time. Allopurinol also increases the concentration of their soluble precursors, xanthine and hypoxanthines. 3

Adalimumab is artificial, man-made injectable protein that prevents inflammatory responses of tumour necrosis factor alpha (TNF α) in "rheumatoid arthritis, psoriatic arthritis, ankylosing spondylitis, and Crohn's disease of the intestine" 4. Inflammation arises to avoid any major damage to body when an injury occurs and it is also the process of injury repair. When inflammation occurs body generates TNF protein. This protein in turn encourages the effects of inflammation and so when it is arthritis; fever, swelling of joints and pain occurs. But when it is Crohn's disease abdominal pain, diarrhoea as well as pain and fever are the signs shown. Failure to acquire treatment for the inflammation of rheumatoid arthritis causes deterioration to joints. Intestinal puncture or thinning of the intestine size arises when Crohn's disease is left untreated. Adalimumab is type of a drug that binds to TNF in the body thus blocking the interaction of p55 & p75 cell surface TNF receptors to TNF. Hence down regulating the effects of TNF, evidently the effects of inflammation on joints and intestine decrease. 4, 5

Patients with rheumatoid arthritis that use adalimumab show decrease in the acute-phase reactants of the inflammation. Serum concentration of interleukins-1, 6 and 8 and granulocyte colony decreases and various other events occur during adalimumab therapy, this in response restores normal immune function. 5


Salbutamol is the generic name of Ventolin; there are also several other names that this medicine is sold under. Salbutamol selectively binds with higher affinity to β2 receptors as opposed to β1 receptors. As salbutamol is β2 agonist it is used for patients with acute asthma, hyperkalaemia especially for patients with renal failure, it is also used as protection for asthma stimulated by exercise. One other use includes is prevention of premature labour. Ventolin's major effect in asthma is relaxation of bronchi by binding to β2 adrenoceptors on the smooth muscle found in bronchial, and various other places; they are the antagonists of bronchcontrictors. Salbutamol catalyses adenosine monophosphate (AMP) from adenosine triphosphate (ATP) by stimulating an enzyme called adenyl cyclase. This then causes bronchodilation hence causing relaxation of the smooth muscle by the activation of protein kinases. The concentration of bound intracellular calcium increases due to phosphorylation of proteins from the activation of protein kinases. Due to the decreased availability of intracellular calcium the actin-myosin linkage is stopped, resulting in relaxation of smooth muscle. The use of salbutamol also inhibits the release of mast cells mediators hence reduced amount of histamine released and the action of mucus clearance by cilia is increased. 6,7


Generic name of Nardil is Phenelzine. Phenelzine is a monoamine oxidase inhibitor (MAOI), antidepressant medicine which causes irreversible inhibition of the enzyme. This antidepressants is a derivative of hydrazine and so irreversibly reduces the activity of the enzyme monoamine oxidase (MAO) in the central nervous system thus triggering the build-up of amine neurotransmitters e.g. serotonin, noradrenaline and dopamine in the neuron, therefore reducing the symptoms of depression. Phenelzine has similar structure to MAO and so binds covalently to MAO when it is oxidised. Nardil is non-selective MAO-inhibitor and so reduces the activity of both the MAO-A and MAO-B enzymes. Additionally, phenelzine raises levels of GABA receptors in the nucleus accumbens and caudate-putamen through its primary metabolites. This explains the reasons for the use of Nardil in treating severe anxiety due to its great efficacy and its anxiolytic properties. 8, 9


Metformin hydrochloride is the generic name for Glucophage. Metformin is used to help regulate body's blood glucose levels with patients with type 2 or non-insulin dependent diabetes. Patients who suffer from diabetes mellitus (type 2 diabetes) have shortage or absence of peptide prohormone called insulin which is produced by the pancreas. Insulin is produced by the β-cells of islets of Langerhans within the pancreas and is responsible for controlling the blood sugar levels. Insulin increases glucose and amino acids uptake and inhibits gluconeogenesis in the skeletal muscle. Insulin also prevents glycogenolysis and promotes glycogen synthesis in the liver. It also increases the glucose and fatty acid uptake in the adipose tissue and prevents lipolysis. Another peptide called glucagon is also a prohormone stored within the vesicles of α-cells, they are released by the sympathetic nervous system in order to reduce glucose concentration in blood. 11, 12

Metformin hydrochloride is well-known as a biguanide and is a kind of antidiabetic medicine. Metformin causes a reduced hepatic glucose output; the drug is only effective when there is sufficient concentration of insulin present. The medicine when taken increases insulin's effects in the tissues such as muscle and liver mostly after meals. Glucophage's antilipolytic effect reduces the serum fatty acid concentration, and so limiting the availability of substrate for gluconeogenesis. Therefore showing improvements in glucose levels which leads to decrease in serum insulin concentration. On administration of Glucophage the use of intestinal glucose increases via non-oxidative metabolism. The products of this process are mainly metabolised as a substrate for gluconeogenesis by the liver and come to effect when hypoglycaemia. AMP-activated kinase (AMPK) is the enzyme which on activation causes metformin to lower serum lipid and blood glucose levels. Peutz-Jeghers protein, LKB1 is the mechanism how metformin works in order to control AMPK

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