Browsing by Author "P.K. Satheeshkumar"

Now showing 1 - 5 of 5

Exosomal biomarkers in colorectal cancer
(Springer International Publishing, 2021) S. Priya; P.K. Satheeshkumar
Colorectal cancer (CRC) is the third most diagnosed cancer in the world which affects the large intestine or rectum. It is a multifactorial disease that gradually develops with the cumulative effects of genetic and epigenetic alterations, which changes the normal colon mucosal layer into invasive form. Recent research interest in CRC relies on the identification of specific biomarkers for early disease diagnosis, adopting better treatment modalities and analysing treatment efficacies. Developments in the omics techniques have identified number of biomarkers. The short oligonucleotides such as microRNA (miRNA) and long noncoding RNA (lncRNA) have proved as better biomarkers among diverse types. Exosomes are 30-150 nm sized membrane bound vesicles formed from endosomes and released to the extracellular space. The differentially expressed proteins, miRNAs, lncRNAs and circular RNAs found in the exosomal vesicles associated with body fluids that could serve as promising biomarkers for CRC. They exhibit entirely different roles in the tumorigenesis and prevention process when compared to the cellular and extracellular biomarkers. In the near future, exosomes will represent a promising non-invasive source of biomarkers for CRC. © The Author(s), under exclusive license to Springer Nature Switzerland AG 2021. All rights reserved.
Natural products from plants: Recent developments in phytochemicals, phytopharmaceuticals, and plant-based neutraceuticals as anticancer agents
(Elsevier, 2020) S. Priya; P.K. Satheeshkumar
Along with all the necessities of life, nature also provides us very low-cost healthcare support. Other than the dietary goods, plants give us many products which have medicinal properties along with the nutritional value and sometimes considered to have even the ability to prevent/delay many lifestyle diseases. The system of traditional practices to treat various diseases has a history may be as old as the human race and was the prominent healthcare management mode until the beginning of the 19th century. The modern medical system evolved alongside the industrial revolution and is the major mode of healthcare all around the world. Though useful in an emergency, several modern medicines are proved to have adverse sideeffects. The “folklore medicines” or tribal medicines enrich the health of common people even in this century without any clinical trial or standardization. Throughout history, natural products have offered a rich source of compounds that found many applications in the fields of medicine, pharmacy, and biology. It would be desirable to look forward to identifying new target molecules from different plant sources and assess their value in this context. The plant-derived molecules can be used as nutraceuticals or therapeutic molecules, which will be easily procurable, less expensive, and with a very less extent of adverse sideeffects. Within the sphere of cancer, several commercialized drugs have been obtained from natural sources. By structural modification of natural compounds, novel synthetic molecules are developed, some of which are as efficient as or even better than that of the natural molecules. The chapter tries to compile the recent developments in the field of anticancer therapeutics research and functional ingredients from plants which are proposed to have anticancer property. © 2020 Elsevier Inc. All rights reserved.
Proteomic approach and expression analysis revealed the differential expression of predicted leptospiral proteases capable of ECM degradation
(Elsevier B.V., 2018) Gunasekaran Dhandapani; Thoduvayil Sikha; Sneha M. Pinto; M. Kiran Kumar; Krishna Patel; Manish Kumar; Vikram Kumar; Jebasingh Tennyson; P.K. Satheeshkumar; Harsha Gowda; T.S. Keshava Prasad; M.G. Madanan
Leptospira, the causative agent of leptospirosis is known to have many proteases with potential to degrade extracellular matrix. However, a multipronged approach to identify, classify, characterize and elucidate their role has not been attempted. Our proteomic approach using high-resolution LC-MS/MS analysis of Triton X-114 fractions of Leptospira interrogans resulted in the identification of 104 proteases out of 130 proteases predicted by MEROPS. In Leptospira approximately 3.5% of the genome complements for proteases, which include catalytic types of metallo-, serine-, cysteine-, aspartic-, threonine- and asparagine- peptidases. Comparison of proteases from different serovars revealed that M04, M09B, M14A, M75, M28A, A01 and U73 protease families are exclusively present in pathogenic form. The M23 and S33 protease families are represented with >14 members in Leptospira. The differential expression under physiological temperature (37 °C) and osmolarity (300 mOsM) showed that proteases belonging to the catalytic type of Metallo-peptidases are upregulated significantly in pathogenic conditions. In silico prediction and characterization of the proteases revealed that several proteases are membrane anchored and secretory, classical as well as non-classical system. The study demonstrates the diversity and complexity of proteases, while maintaining conservation across the serovars in Leptospira and their differential expression under pathogenic conditions. © 2018 Elsevier B.V.
Reactive Oxygen Species (ROS) and ROS Scavengers in Plant Abiotic Stress Response
(Springer Nature, 2024) Aakanksha Singh; P.K. Satheeshkumar
The surroundings in which plants live experience fluctuations in every moment. Highly dynamic processes in the cells in response to these changes in the outside environment restore the equilibrium necessary for normal metabolism. Being sessile living beings' plants are affected by the changes in their surroundings much more than animals, who can move themselves to a more comfortable environment. Metabolic processes produce certain bi-products that play critical roles in living cells. They present in the cells under normal conditions within a permissible level and may increase their concentration under extreme conditions like stress. Reactive oxygen species or “ROS” is one of those by-products that have multiple roles in living cells. Nearly 1–2% of the oxygen that enters the cells is converted to ROS of different types such as singlet oxygen, superoxide radical, hydroxide radical, and hydrogen peroxide, which are inevitable components in activating many molecular pathways in cells. The sensitive balance in terms of the amount of ROS present in a cell at a time is taken care of by a group of molecules known as ROS scavengers, which are part of the antioxidant machinery in the cells. While the redox signalling pathways mediated by the ROS under normal conditions are beneficial for plant growth, and development, the pathways activated by the ROS under stress conditions have a negative effect on plants. Even though the ROS induces the ROS scavenger's production and activity, depending on the intensity and duration of the stress it may be beneficial or ineffective. This chapter discusses about different types of ROS and ROS scavengers, the conditions leading to their origin, the role played by them under normal and stressed conditions, and the major organelles involved in the ROS signalling pathways. © The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2024.
Triton X-114 Fractionated Subcellular Proteome of Leptospira interrogans Shows Selective Enrichment of Pathogenic and Outer Membrane Proteins in the Detergent Fraction
(Wiley-VCH Verlag, 2020) Sikha Thoduvayil; Gunasekaran Dhandapani; Rahul Brahma; Rex Devasahayam Arokia Balaya; Kiran K. Mangalaparthi; Krishna Patel; Manish Kumar; Jebasingh Tennyson; P.K. Satheeshkumar; Mahesh J. Kulkarni; Sneha M. Pinto; T. S. Keshava Prasad; Madathiparambil G. Madanan
The Triton X-114-based solubilization and temperature-dependent phase separation of proteins is used for subcellular fractionation where, aqueous, detergent, and pellet fractions represents cytoplasmic, outer membrane (OM), and inner membrane proteins, respectively. Mass spectrometry-based proteomic analysis of Triton X-114 fractions of proteomic analysis of Leptospira interrogans identified 2957 unique proteins distributed across the fractions. The results are compared with bioinformatics predictions on their subcellular localization and pathogenic nature. Analysis of the distribution of proteins across the Triton X-114 fractions with the predicted characteristics is performed based on “number” of unique type of proteins, and “quantity” which represents the amount of unique protein. The highest number of predicted outer membrane proteins (OMPs) and pathogenic proteins are found in aqueous and pellet fractions, whereas detergent fraction representing the OM has the highest quantity of OMPs and pathogenic proteins though lower in number than the aqueous and pellet fractions. This leaves the possibility of an upsurge in pathogenic proteins and OMPs on the OM under pathogenic conditions suggesting their potential use to combat leptospirosis. Further, the Triton X-114 subcellular fractions are more correlated to enrichment of pathogenic proteins predicted by MP3 software than predicted localization. © 2020 Wiley-VCH GmbH