RNA interference (RNAi) is one of the most exciting and revolutionary new approaches to therapies that have attracted considerable amount of attention within the last few decades. It has been found that gene expression may be controlled at the level of messenger RNA via noncoding RNAs. RNAi is an important pathway that leads to explicit gene silencing and down regulating.
Gene therapy is a medical intervention that uses genes for the treatment or prevention of disease. If the gene of interest is delivered properly to the desired site, then this strategy would allow the direct insertion of a gene into a specific cell. Therefore, different types of biocompatible nanoparticles have been used to deliver genes intended for gene therapy to overcome the disadvantages encountered with the traditional methods used for genetic material delivery.
Nanoparticles as therapeutics can be delivered to targeted sites, including locations that cannot be easily reached by standard drugs. For instance, if a therapeutic can be chemically attached to a nanoparticle, it can then be guided to the site of the disease or infection by radio or magnetic signals. These nanodrugs can also be designed to “”release”” only at times when specific molecules are present or when external triggers (such as infrared heat) are provided. At the same time, harmful side effects from potent medications can be avoided by reducing the effective dosage needed to treat the patient. By encapsulating drugs in nanosized materials (such as organic dendrimers, hollow polymer capsules, and nanoshells), release can be controlled much more precisely than ever before.
Drugs are designed to carry a therapeutic payload (radiation, chemotherapy or gene therapy) as well as for imaging applications. Many agents, which cannot be administered orally due to their poor bioavailability, will now have scope of use in therapy with the help of nanotechnology. Nano-formulations offer protection for agents vulnerable to degradation or denaturation when exposed to extreme pH, and also prolong half-life of a drug by expanding retention of the formulation through bioadhesion. Another broad application of nanotechnology is the delivery of antigens for vaccination. Recent advances in encapsulation and development of suitable animal models have demonstrated that microparticles and nanoparticles are capable of enhancing immunization.
In therapy: Nanotechnology can provide new formulations of drugs with less side effects and routes for drug delivery. Diseases should be diagnosed and cured before symptoms even manifest themselves, this is optimum. Nucleic acid diagnostics play a crucial role in that process, as they allow the detection of pathogens and diseased cells at such an early symptomless stage of disease progression that effective treatment is more feasible.
In Diagnosis: Main diagnostic methods for most diseases depend on the manifestation of visible symptoms so that doctors know there is a disease. But by the time those symptoms have appeared, treatment may have a decreased chance of being effective. Therefore the earlier a disease can be detected, the better the chance for a cure is.
Applications: Drug loading onto nanoparticles increase cell and tissue distribution this enhance drug efficacy and reduces drug toxicity
They can be effectively used to deliver relevant drugs to the brain overcoming the presence of blood–brain barrier (as in meninges)
Nanosystems have capacity of selective localization in inflammation.
The effect of the nanosystems in the tumors or inflamed tissues through better transmission and retention improved by increasing vascular permeability coupled with an impaired lymphatic drainage in tumors.
Nanoproducts can be accumulated at higher concentrations than normal drugs