Pl. Rm. Palaniappan

Fourier transform infrared study of protein secondary structural changes in the muscle of Labeo rohita due to arsenic intoxication.

Protein is one of the most important nutrients in human diets and fish has become an increasingly important source of protein in most of the developing countries. Among the various fish tissues, muscle is the major contributor of proteins and the whole mass of the body. The goal of this study is to assess the changes in the biochemical compositions in general, and the protein structural changes in particular, in the muscle of Labeo rohita fingerlings due to arsenic intoxication using Fourier transform infrared (FT-IR) spectroscopy. The results of the present study indicate that arsenic intoxication induces significant alteration in the major biochemical compositions such as proteins, lipids and nucleic acids of Labeo rohita. Further, the results clearly indicate considerable change in the composition of muscle proteins due to arsenic intoxication. It is therefore concluded that FT-IR spectroscopy can be a successful detection tool in toxicological research.

The effect of titanium dioxide on the biochemical constituents of the brain of Zebrafish (Danio rerio): an FT-IR study.

During recent years, the use of nanoparticles (NPs) in commercial products and industrial applications has increased greatly. One of the most widely used nanoparticles is titanium dioxide (nTiO(2)). It is a very versatile compound that has many uses, depending on its particle size. In the present paper an attempt is made to study the effect of TiO(2) nanoparticles and its bulk material on the biochemical constituents of the brain of Zebrafish (Danio rerio) by using FT-IR technique. FT-IR spectra reveals significant differences in absorbance intensities between the control and TiO(2) exposed brain tissues, reflecting alterations on the major biochemical constituents such as proteins, lipids and nucleic acids in the brain tissues of D. rerio due to TiO(2) exposure. The results further reveal that TiO(2) nanoparticles are more toxic than their bulk counterparts. The higher ratio of integrated area of carbonyl-to-CH(2) peaks (1743 cm(-1):1458 cm(-1)) observed in the present study in the nTiO(2) exposed brain tissues suggests that lipids are being oxidized. Since oxidation can cause an increase in carbonyls and a degradation of lipids, both of these changes could be contributed to the elevated ratio. Further, the observed decreasing ratio of integrated areas of both 1458 cm(-1):1542 cm(-1) and 1743 cm(-1):1542 cm(-1) in the TiO(2) exposed tissues suggests that lipid degradation predominates over carbonyl formation. The observed changes in the biochemical constituents in the brain tissues of D. rerio could be due to the overproduction of ROS.

FTIR study of the effect of nTiO2 on the biochemical constituents of gill tissues of Zebrafish (Danio rerio).

In the present study, an attempt is made to assess the changes in the biochemical contents in general, and the protein structural changes in particular, in the gill tissues of Zebrafish (Danio rerio) due to titanium nanoparticles and their bulk counterpart using FTIR spectroscopy. The FTIR spectra show that the intensity differences between the control and titanium-exposed tissues are remarkable. For example, TiO(2)-exposed tissues show higher intensities at amide I and amide II of proteins, but lower at 2924 cm(-1) (CH(2) asymmetric stretching of lipids), 2853 cm(-1) (CH(2) symmetric stretching of lipids) and 1744 cm(-1) (CO stretching of phospholipids) when compared with the control tissues. This suggests that there is an increase or decrease in the percentage of a certain types of biomolecules relative to the total infrared-active constituents in the gill tissues. The curve-fitting analysis suggests an increase in alpha-helical structure and a decrease in beta-sheet structure due to TiO(2) exposure. These results confirm that the structural conformation of proteins in fish gill tissues was significantly influenced by TiO(2) exposure. Further, the changes are more due to nTiO(2) when compared to TiO(2) bulk, suggesting that nTiO(2) are affecting the biochemical constituents more than their bulk counterpart.

Chemopreventive efficacy of piperine in 7,12-dimethyl benz [a] anthracene (DMBA)-induced hamster buccal pouch carcinogenesis: An FT-IR study

The present study is designed to investigate the effect of piperine in modifying the carcinogenic process, as well as biochemical alterations at the molecular level during DMBA-induced hamster buccal pouch carcinogenesis by FT-IR spectroscopy. Specific changes were noticed in the FT-IR spectral features of DMBA-induced hamster buccal pouch carcinoma. These alterations include structural changes of proteins and possible increase of its content, an increase in the nuclear-to-cytoplasm ratio, an increase in the relative amount of DNA, an enhancement in the phosphorylation of proteins, a loss of hydrogen bonding of the C-OH groups in the amino acid residues of proteins and diminished lipid peroxidation which were accompanied by a significant reduction in the relative amount of lipids compared to untreated control animals. Administration of piperine significantly increased the levels of lipid peroxidation and decreased the levels of proteins and nucleic acid content that were found to increase in oral cancer bearing animals. In conclusion, the results of the present study suggest that piperine may exert its chemopreventive effect by modulating the biochemical changes at the molecular level during DMBA-induced hamster buccal pouch carcinogenesis which can be detected using FT-IR spectroscopic technique.

Morphological changes due to Lead exposure and the influence of DMSA on the gill tissues of the freshwater fish, Catla catla.

Catla catla fingerlings were reared in freshwater and exposed to 15.5 ppm concentration of lead for 60 days. The morphological changes on the gill of the C. catla fingerlings due to lead intoxication and the effect of DMSA (meso 2,3-dimercaptosuccinic acid) on the affected tissues were observed using Scanning Electron Microscope. It has been found that the lead treated gill tissues showed certain marked changes, such as cell hypertrophy, alteration in the lamellar surfaces, epithelial hyperplasia and the fusion of adjacent lamellae. The antidote DMSA treatment reduces the toxic effects and helps the recovery of gill tissue and its return to the level of the control/normal.

The effect of arsenic exposure and the efficacy of DMSA on the proteins and lipids of the gill tissues of Labeo rohita

Arsenic is a naturally occurring, highly toxic environmental pollutant. Fourier transform infrared (FT-IR) spectroscopy is a non-disturbing technique which provides quantitative information about the molecular composition of biological samples. The aim of this work is to study the compositional and structural changes at the molecular level occurring in gill tissues of Labeo rohita fingerlings due to arsenic exposure for various exposure periods by using FT-IR spectroscopic technique. The results of the present study suggest that arsenic exposure causes significant changes on the major biochemical constituents such as proteins, lipids and nucleic acids in the gill tissues of L. rohita. The changes are more pronounced as the period of exposure is increased. The significant decrease in the intensity and area of the amide I peak and CH(3) asymmetric stretching band suggests an alteration in the protein profile and lipid levels respectively, due to arsenic exposure. The amide A peak shifts suggests a change in the level of protein amide hydrogen bonding due to arsenic exposure. Further, the treatment with meso-2,3-dimercaptosuccinic acid (DMSA) improves the levels of biochemical constituents significantly, which suggest that DMSA treatment reduces the toxic effects and helps the recovery of gill tissues and its return to the level of the control.

The study of the changes in the biochemical and mineral contents of bones of Catla catla due to lead intoxication.

In the present study, an attempt has been made to analyze the changes in the biochemical and mineral contents of lead‐intoxicated bones of Catla catla at subchronic (15.5 ppm) exposure, and also to determine whether the effects of Pb intoxication can be reversed with the chelating agent meso 2, 3‐dimercaptosuccinic acid (DMSA) on the bones of freshwater fingerlings Catla catla by using Fourier transform infrared (FT‐IR) spectroscopy, X‐ray diffraction (XRD), and atomic absorption spectrophotometer techniques. The FT‐IR spectra of the lead‐exposed bones show significant alteration in the biochemical constituents. The XRD analysis showed a decrease in crystallinity due to lead exposure. Further, the Ca, Mg, and P contents of the lead‐exposed bones were less than those of the control group, and there was an increase in the mineral contents of the bones after DMSA treatment. In conclusion, the present study suggests that the subchronic lead exposure results in severe loss of bone minerals. The overall decrease in the FT‐IR band intensity of Pb‐exposed bones relative to the control indicates a decrease in the biochemical constituents like proteins and lipids. The increase in the band intensity after treatment with chelating agent DMSA indicates increased biochemical constituents, showing that the subchronic effects of lead can be reversed by DMSA. The amide I bands observed at 1654 cm−1 in the present study suggest that the protein is dominated by α‐helical structure.

FT-IR study of the effect of lead and the influence of chelating agents, DMSA and D-Penicillamine, on the biochemical contents of brain tissues of Catla catla fingerlings

Abstract.The goal of this study was to investigate the effect of lead and the influence of chelating agents,meso 2, 3-dimercaptosuccinic acid (DMSA) and D-Penicillamine, on the biochemical contents of the brain tissues of Catla catla fingerlings by Fourier Transform Infrared Spectroscopy. FT-IR spectra revealed significant differences in absorbance intensities between control and lead-intoxicated brain tissues, reflecting a change in protein and lipid contents in the brain tissues due to lead toxicity. In addition, the administration of chelating agents, DMSA and D-Penicillamine, improved the protein and lipid contents in the brain tissues compared to lead-intoxicated tissues. Further, DMSA was more effective in reducing the body burden of lead. The protein secondary structure analysis revealed that lead intoxication causes an alteration in protein profile with a decrease in α-helix and an increase in β-sheet structure of Catla catla brain. In conclusion, the study demonstrated that FT-IR spectroscopy could differentiate the normal and lead-intoxicated brain tissues due to intrinsic differences in intensity.

A study of the subchronic effects of arsenic exposure on the liver tissues of Labeo rohita using Fourier transform infrared technique

In this work, an attempt has been made to study the subchronic effects of arsenic exposure on the biochemical composition; mainly proteins of the liver tissues of Labeo rohita fingerlings by using Fourier transform infrared (FT‐IR) spectroscopic technique. The study was carried out using a Perkin Elmer‐Spectrum Rx1 spectrometer. Because of arsenic exposure, significant reductions in the intensity as well as area of amide bands have been observed in the liver tissues. The decreased intensity of the amide bands could be interpreted as the result of alteration of the protein synthesis due to the high affinity of metal compounds towards different amino acid residues of proteins. Further, meso‐2, 3‐dimercaptosuccinic acid (DMSA) treatment shows the recovery of the protein content in the liver tissues. To confirm that the changes observed are only due to the bio‐accumulation of arsenic, the concentration of arsenic in the liver tissues of Labeo rohita was determined by using Inductively Coupled Plasma‐Optical Emission Spectrometry (ICP‐OES). It is observed that the arsenic level in the control tissues is found to be below detectable limit, whereas the arsenic exposed liver shows an accumulation of 66.68 ± 0.43 μg/g and DMSA treatment reduces the arsenic content to 17.96 ± 0.19 μg/g. In conclusion, this study gives clear evidence that the use of FT‐IR spectroscopy is a powerful approach to achieve more insight into the protein alterations caused by arsenic.

Arsenic-Induced Biochemical Changes in Labeo rohita Kidney: An FTIR Study

ABSTRACT Arsenic is a toxic heavy metal that occurs naturally in water, soil, and air. It is widespread in the environment as a consequence of both anthropogenic and natural processes. In the current study, an attempt has been made to analyze the arsenic-induced molecular changes in macromolecular components like proteins and lipids in the kidney tissues of edible fish Labeo rohita using Fourier transform infrared (FTIR) spectroscopy. The FTIR spectrum of kidney tissue is quite complex and contains several bands arising from the contribution of different functional groups. The detailed spectral analyses were performed in three distinct wave number regions, namely 3600–3050 cm−1, 3050–2800 cm−1, and 1800–800 cm−1. The current study shows that the kidney tissues are more vulnerable to arsenic intoxication. FTIR spectra reveal significant differences in both absorbance intensities and areas between control and arsenic-intoxicated kidney tissues; this result indicates that arsenic intoxication induces significant alteration on the major biochemical constituents such as lipids and proteins and leads to compositional and structural changes in kidney tissues at the molecular level. The current study confirms that FTIR spectroscopy can be successfully applied to toxicologic and biological studies.