Post-transactional modification of collagen – role of glycosylation

Signaling pathways in chromium induced apoptosis

Apoptosis is a unique morphological pattern of cell death having the characteristic features of chromatin condensation and membrane blebbing.  It role in maintaining homeostasis , regulating many developmental process and also elimination of unwanted and damaged cells has been realized in recent times .The mechanisms involved are being worked out in many laboratories the world over. In our laboratory, we are working on the signaling mechanisms involved in chromium toxicity, since chromium is an important element finding use in many industries and leather industry is one among them. Chromium in various valence states viz., Cr(VI), Cr(V) and Cr(III) have been investigated in our laboratory for their cytotoxic properties. Cr(V) complexes and Cr(III) complexes soluble at the physiological pH values have been used in our studies. The apoptotic cell death of human peripheral blood lymphocytes induced by chromium(III) has been reported first by us.  Some of the signaling molecules which participate in the apoptotic process have been identified as reactive oxygen species (ROS), Src- family tyrosine kinases, and caspase-3. Cr (III) picolinate has been a popular nutritional supplement as well as used in treating the diabetics in the Western countries for a few years now and its use in India is increasing. Some of the Cr(III) complexes which we have employed in our study includes the Cr(III) liganded to aromatic amine groups. Since Cr (III) picolinate bears similarity in this respect as well as there are some controversies regarding the safety of this compound in human use, we are now addressing to the effects of Cr (III) picolinate in cells. Furthur the synthesis of antioxidant proteins such as metallothionein in the presence of some chromium (III) complexes and not due to Cr(VI) has been demonstrated and other antioxidant mechanisms are being probed. The various isoforms of metallothionein induced by Cr (III) have been identified. Investigations on the expression of genes in the presence of chromium through microarray techniques will be taken up in order identify the biomarkers in chromium exposure.  Other metals and organic compounds which find use as drugs are being investigated for their cytotoxic properties.

Enzymes for processing skins and hides in leather industry

Other areas of research interest include the proteins of the skin and their susceptibility to enzymes, which bear relevance to the leather industry. Paradigm shifts from chemicals to enzymes in the processing of leather is the need of the hour. Studies on the biochemical action of enzymes on the skin proteins have been carried out in order provide biochemical explanation for the utility of enzymes for unhairing in the leather industry.

Studies on the polymorphism of Collagen from hard and mineralized tissues from different organisms are also being pursued.