|Nelly M. Dabbour*|
|Corresponding Author: Dr. Nelly M. Dabbour, Assistant Professor Medical Research Institute Alexandria University, Egypt.|
|Received: June 30, 2016; Accepted: July 18, 2016; Published: Nov 8, 2016;|
|Citation: Dabbour M. (2016) Technologies Used in Drug Research. J Pharm Drug Res, 1(1): 7-8.|
|Copyrights: ©2016 Dabbour M. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.|
From the dawn of civilization, people have been dreaming of healthy and long-life, therefore, drug research become one of the most important field in the health community. To achieve a science revolution in discovering treatments, many technologies were used by the researchers to help many patients to defeat their incurable diseases.
Drug Delivery System (DDS):
It is a nanotechnological technique that has optimal dose and longer lasting effect with less quantity and less side effects. The main goal of any DDS is to maximize bioavailability, whatever the drug is administered topically (1) or systemically (2). Thus, the drug becomes more effective and more pleasant.
As many drug molecules are not able to pass through the cell membrane because it is a nonpolar membrane and the drug molecules are polar; encapsulating the polar drug in a nonpolar coating will act as protective environment and aid to easily pass through the cell membrane. The encapsulation could be microparticles or nanoparticles (dendrimers, liposomes, buckyballs, quantum dots, and nanoshells), and could be prepared as organic (e.g. polymers) (2) or inorganic (e.g. gold) (3).
The uses of DDS are numerous; firstly, it converts the molecules from poorly soluble and poorly absorbed into deliverable drug as its particle size is reduced (5). Secondly, it has the concept of targeted therapy which the drug can be selectively delivered to cells as a silver bullet to the diseased cells leaving the healthy cells untouched and limiting drug distribution to target organ, which decreases its side effects, improves its efficacy (6).
Finally, it provides a drug release over an extended period of time, through drug accumulation in target tissues and prevention of rapid clearance (7), leading to increase in the half-life, amelioration in the therapeutic index and reduction in immunogenicity (8).
Monoclonal Antibody (MAb):
It is a biotechnological molecule produced from a single B cell clone and can bind to a single type of antigen binding site. It is homogenous that bind to only a single epitope on the antigen of the cell.
This laboratory-engineered antibody mimics the body’s immune system; first of all, it makes the diseased cells obvious if they are not recognized by the immune system, this is achieved by attaching to the cell as a mark so the immune system can detect it. Or, it stimulates the immune system to its job and defends the body against diseases such as cancer (9). As well as, it protects the body from infection by binding to the antigen of the virus and neutralizing its biological effect (10).
Also, it has a crucial role in cancer therapy; it blocks the signals of growth factors on the malignant cells preventing them from growing and dividing faster. On the other hand, it inhibits angiogenesis leading to reduction in nutrients and oxygen supply, and then tumor shrinkage and metastasis prevention. It has another role in arresting checkpoints, of the cell cycle, used by the tumor to suppress the immune system (11).
In addition, it is effective in autoimmune diseases such as rheumatoid arthritis, Crohn’s disease, ankylosing spondilitis, ulcerative colitis and renal diseases; through the inhibition of the Tumor Necrosis Factor (TNF-α) (12), or by targeting B‑cells (13). Finally, it acts as immunosuppressant in organ transplantation to overcome rejection; this is done by targeting T-cell receptors or B-cells, or by inhibiting one of the cytokines (14).
Drug Discovery and Design:
Drug discovery is a process where researchers attempt to improve an existing drug or invent a new one with different chemical structure. It should be more potent or safer than any drug of a similar category (15).
This is accomplished by having a good understanding of the causes and the mechanism of the disease, choosing a valid target molecule (i.e. a biomolecule) involved in that disease which can be modulated by the drug, and then searching for a lead drug molecule that can act on the biological target to alter the disease through inhibition or stimulation. If succeeded, the lead compound becomes a new medicine.
A biological target can be identified when there is abnormality in some biochemical functions, or an increase/decrease in production of some intermediates. Thus, it can be an enzyme (16), a receptor (17) or a nucleic acid (18). Biological target validation needs the suitable animal models and the latest techniques in gene targeting to help detecting a secondary target that the chosen drug can bind to (19); this interaction may cause adverse reaction. This is because the drug has to binds to a single target only.
When the drug binds to the biomolecule, its action is shown; this is done by drug designing through computer software which design ligands and identify the biological target and its active site accurately. The synthesized structures are predictive models for the evaluation of biological activity.
To be able to predict molecular-interactions in computer-aided drug design (CADD), development of pharmacophore-based and molecular docking and scoring techniques are involved; because docking predicts the conformation and orientation of ligand within the binding site of the target. This process is carried out for accurate structural modelling and correct prediction of the biological activity (20).
The biomolecule structure is identified by X-ray crystallography or nuclear magnetic resonance to predict the potential affinity of the lead drug. After that, the designed drug is tested on the target biomolecule; the scientists follow the compound absorption, distribution, metabolism and excretion, and also detect any toxicity. The compound that succeeds in the initial test is altered to make it safer and more effective through the change in their properties. After many optimizations, the final compound becomes a drug candidate.
When searching the effective technologies that quest to achieve the best quality of life, it is revealed that it comes from the development of basic chemistry and human biology. Thus, technologies encourage the thriving of the drug research development.
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