Hepatitis-C Virus (HCV) belongs to the Flaviviridae family and is the leading cause of chronic liver disease globally. It is estimated to infect about 170 million people around the world (WHO, 1997). Chronic HCV infection frequently leads to liver fibrosis and cirrhosis, and is associated with the occurrence of hepatocellular carcinoma. Acute infection occurs in only a few patients. In most cases the virus results in chronic infection taking 10–20 years before the emergence of liver disease, which is often accompanied by only mild or vague symptoms. Despite the seemingly benign onset of the disease, a significant number of patients with chronic hepatitis develop cirrhosis and its complications.HCV infects only humans and chimpanzees; there are no small-animal[..]

The hair follicle is a three-dimensional tube, composed mainly of epithelial cells that protrude down through the epidermis and dermis of the skin, enveloping at its base the mesenchyme-derived dermal papilla. These hair follicle acts as a sensory organ and immunologic sentinel for the skin. Hairs detect mechanical stimuli above the surface of the skin, and the slightest bend in a hair activates Neuroreceptors in the follicle, relaying important sensory information to the Nervous System. The Langerhans' cells (Dendritic Antigen-Presenting Cells) at the opening of the follicle detect surface pathogens and activate the immune system. The hair follicle has a complex immunologic profile, with immunologically "privileged" matrix at its base, and a complement of[..]

The ESRs (Estrogen Receptors) are ligand-dependent transcription factors and are important Nuclear Hormone Receptors that act as regulators of cell growth, differentiation and malignant transformation. Transcriptional activation by ESRs is accomplished through specific and general cofactor complexes that assemble with the receptor at target promoters to regulate transcription. The chief ligand for ESR is the ovarian steroid hormone Estrogen, which has a primary role in the establishment and maintenance of reproductive function (Ref.1). Naturally occurring forms of Estrogen are Estradiol, Estriol, and Estrone. Estradiol is the most commonly occurring form of Estrogen in non-pregnant women. Binding of Estrogen to the ESR promotes a conformational change in the receptor[..]

Retinoic Acid, a lipophilic molecule and a metabolite of Vitamin-A (all-trans-Retinol), affects gene transcription and modulates a wide variety of biological processes like Cell Proliferation, Differentiation, including Apoptosis. Retinoic Acid mediated gene transcription depends on the rate of transport of Retinoic Acid to target cells and the timing of exposure of Retinoic Acid to RARs (Retinoic Acid Receptors) in the target tissues. The all-trans-Retinoic Acid, the Carboxylic Acid form of Vitamin-A is of biological significance since it has high circulating levels than other isomers of Retinoic Acid. The targets of all-trans-Retinoic Acid and RARs include a multitude of Structural genes, Oncogenes, Transcription Factors and Cytokines. Although biologically active[..]

ILK(Integrin-linked kinase) is a key scaffold protein that localizes to focal adhesions, acts as a central component of a heterotrimer (the ILK–PINCH–parvin complex). Since its discovery, ILK has been demonstrated to have an essential role in connecting the cytoplasmic tail of β subunits of integrins to the actin cytoskeleton, and in regulating actin polymerization. Within this pivotal position, ILK has been shown to interact with many intracellular proteins through PINCH or parvin to mediate diverse arrays of biological events,or to mediate cell responses induced by the interaction of integrins with the ECM(extracellular matrix)(Ref.1). Several adaptor proteins with Actin binding properties interact with the C-terminus (COOH-terminus) of ILK.[..]

Oxidative stress/Hypoxia is induced by a wide range of environmental factors including UV stress, pathogen invasion (hypersensitive reaction), oxygen shortage, etc. Generation of ROS (Reactive Oxygen Species) is characteristic feature of such stress conditions. Of the ROS, both Hydrogen Peroxide and Superoxide are produced in a number of cellular reactions and by various enzymes such as Lipoxygenases, Peroxidases, NADPH Oxidase, Xanthine Oxidase, etc to name a few. The main cellular components susceptible to damage by free radicals are lipids (peroxidation of unsaturated fatty acids in membranes), proteins (denaturation), carbohydrates and nucleic acids. Consequences of oxidative stress depend on tissue and/or species (i.e. their tolerance to Anoxia), on membrane[..]

Pancreatic ductal adenocarcinoma is the most common pancreatic neoplasm and as its name suggests it arises from ductal epithelial cells of the pancreas. Other subtypes of pancreatic neoplasms include benign and malignant cystic lesions, mucin producing tumor, acinar cell carcinoma, adenosquamous carcinoma, lymphomas and sarcomas. Pancreatic ductal adenocarcinoma evolves from a progressive cascade of cellular, morphological and architectural changes from normal ductal epithelium through preneoplastic lesions termed PanIN (Pancreatic Intraepithelial Neoplasia). These PanIN lesions are in turn associated with somatic alterations in canonical oncogenes and tumor suppressor genes. The molecular pathogenesis of human pancreatic ductal adenocarcinoma involves the temporal and[..]

ESCs (Embryonic stem cells) are Pluripotent cells derived from the ICM (Inner Cell Mass) of Blastocyst-stage embryos. These cells have two distinctive properties: an unlimited capacity for Self-renewal and Pluripotency. The capability for Self-renewal and the Pluripotency of ESCs seem to be under the control of multiple transcriptional factors, most common among them being Nanog (Nanog homeobox), Oct4 (Octamer Binding Transcription Factor-4) and SOX2 (SRY (Sex Determining Region-Y) Box-2). Functions of these transcription factors depend on the stage of development of a Pluripotent cell, indicating that these factors function in combination with other processes. The activity of these transcription factors also depends on the accessibility[..]

ESCs (Embryonic Stem Cells) are Pluripotent cells capable of differentiating into any cell type of the body. Only three species of Mammals have yielded long-term cultures of self-renewing ESCs- Mice, Monkeys, and Humans. Human ESCs are derived from Blastocysts, multicellular structures originating from four cleavages of fertilized oocytes. Isolated from the ICM (Inner Cell Mass) of Blastocysts, the ESCs retain properties of self-renewal and the potential to be committed and to differentiate toward most cell lineages. They are able to spontaneously give rise to different progenies of the three embryonic layers, namely, the Ectoderm, the Mesoderm and the Endoderm. The Pluripotency of ESCs has attracted great attention for their potential use in tissue and cell therapy.[..]

MI(Myocardial infarction ) causes the loss of cardiac tissue and scar formation, which ultimately lead to heart failure. According to the World Health Organization, heart failure initiated by MI and coronary artery disease accounts for 29% of deaths worldwide. However, human heart tissue does not regenerate spontaneously, thus “regenerative medicine” represents a promising alternative treatment for MI. Cardiac tissue regenerative medicine involves cardiomyocyte regeneration, neovascularization, and paracrine cytokines, which have anti-inflammatory, anti-apoptotic, and anti-remodeling effects. During the last decade, stem cells have become promising candidates for regenerative medicine not only because of their capacity of differentiation toward[..]

Cellular Lipid homeostasis in mammalian cells is regulated through the end-product feedback regulation of Lipid synthesis by a family of membrane-bound transcription factors designated SREBPs (Sterol Regulatory Element–Binding Proteins) that control the flux of cellular metabolites into the major Lipid pathways. The mammalian cell continuously adjusts its Sterol content by regulating levels of key Sterol synthetic enzymes and levels of Lipoprotein receptors that mediate uptake of Cholesterol-laden particles. Control is brought about by SREBPs, which monitor the Sterol-regulated transcription and directly activate the expression of more than 30 relevant genes dedicated to the synthesis and uptake of Cholesterol, Fatty Acids, Triglycerides, and Phospholipids, as well[..]

The cell membranes do not simply serve as barriers to separate the inside of the cell from the outside or to delineate different intracellular compartments. These membranes also serve as a platform for cell signaling by allowing specific sets of proteins to interact. Phospholipids are major structural constituents of the cell membranes. In the cell membranes of neurons, the two most prevalent Phospholipids include PC (Phosphatidylcholine) and PS (Phosphatidylserine). When cell membranes are stimulated by cell signaling activity, enzymes (called Phospholipases) free lipid messengers from these reservoirs. The lipid messengers then regulate and interact with other signaling cascades to contribute to the development, differentiation, function protection, and repair of the[..]