Indian Journal of Biochemistry & Biophysics 

About: Indian Journal of Biochemistry & Biophysics is an academic journal published by NISCAIR. The journal publishes majorly in the area(s): Biology & Chemistry. It has an ISSN identifier of 0301-1208. Over the lifetime, 2921 publications have been published receiving 29125 citations.

A modified spectrophotometric assay of superoxide dismutase.

Abstract: A simple and rapid method for the assay of superoxide dismutase in biological samples is described. Present method takes advantage of the inhibition of NADH-dependent-nitroblue tetrazolium reduction by the dismutase. Inhibition of the chromogen formation by superoxide dismutase was linear with increase in enzyme concentrations. The chromogen extract in butanol was stable even up to 48 hr. Superoxide dismutase activity, as assayed by the modified method, was in good agreement with that obtained using other methods.

Nitric oxide and immune response.

Abstract: Nitric oxide (NO), initially described as a physiological mediator of endothelial cell relaxation plays an important role in hypotension. It is an intercellular messenger and has been recognized as one of the most versatile players in the immune system. Cells of the innate immune system--macrophages, neutrophils and natural killer (NK) cells use pattern recognition receptors to recognize molecular patterns associated with pathogens. Activated macrophages then inhibit pathogen replication by releasing a variety of effector molecules, including NO. In addition to macrophages, a large number of other immune system cells produce and respond to NO. Thus, NO is important as a toxic defense molecule against infectious organisms. It also regulates the functional activity, growth and death of many immune and inflammatory cell types including macrophages, T lymphocytes, antigen-presenting cells, mast cells, neutrophils and NK cells. However, the role of NO in non-specific and specific immunity in vivo and in immunologically mediated diseases and inflammation is poorly understood. This review discusses the role of NO in immune response and inflammation and its mechanisms of action in these processes.

Microtiter plate assay for superoxide dismutase using MTT reduction by superoxide.

Abstract: A simple microtiter plate based colorimetric assay for superoxide dismutase is described. The method, involves generation of superoxide by pyrogallol autoxidation and the inhibition of superoxide dependent reduction of the tetrazolium dye MTT [3-(4,5-dimethyl-thiazol-2-yl) 2,5-diphenyl tetrazolium bromide] to its formazan, measured at 570 nm. The reaction was terminated by the addition of dimethyl sulfoxide (DMSO) which also helps to solubilize the formazan formed and the colour evolved was stable for many hours. The method was compared with other known methods to measure the activity of purified erythrocyte Cu,ZnSOD and superoxide dismutase activity from various rat tissues. This procedure involves inexpensive reagents, allows a rapid and sensitive measurement of SOD activity and the microtiter plate assay is suitable for use with large number of samples.

Methods for estimating lipid peroxidation: an analysis of merits and demerits.

Abstract: Among the cellular molecules, lipids that contain unsaturated fatty acids with more than one double bond are particularly susceptible to action of free radicals. The resulting reaction, known as lipid peroxidation, disrupts biological membranes and is thereby highly deleterious to their structure and function. Lipid peroxidation is being studied extensively in relation to disease, modulation by antioxidants and other contexts. A large number of by-products are formed during this process. These can be measured by different assays. The most common method used is the estimation of aldehydic products by their ability to react with thiobarbituric acid (TBA) that yield 'thiobarbituric acid reactive substances' (TBARS), which can be easily measured by spectrophotometry. Though this assay is sensitive and widely used, it is not specific and TBA reacts with a number of components present in biological samples. Hence caution should be used while employing this method. Wherever possible this assay should be combined with other assays for lipid peroxidation. Such methol are measurement of conjugated dienes, lipid hydroperoxides, individual aldehydes, exhaled gases like pentane, isoprostanes, etc. The modern methods also involve newer techniques involving HPLC, spectrofluorimetry, mass spectrometry, chemiluminescence etc. These and other modem methods are more specific and can be applied to measure lipid peroxidation. There are certain restraints, in terms of high cost and certain artifacts, and these should be considered while selecting the method for estimation. This review analyses the merits and demerits of various assays to measure lipid peroxidation.