Chapters authored
Emerging Role of Pancreatic β-Cells during Insulin Resistance
In today’s world, type 2 diabetes has become a part of every household and leads to various complications including high blood sugar level, diabetic retinopathy, diabetic foot, diabetic nephropathy and diabetic neuropathy. Yet people lack awareness about this disease and its detrimental effects. For a better understanding of this disease we must know about the causes and preventive measures since the medications used in treating type 2 diabetes have moderate to severe side effects. Type 2 diabetes is characterized by loss of insulin receptor activity in skeletal muscle and adipocytes, compensatory insulin secretion from pancreatic β-cells, β-cell dysfunction and death. The proper functioning of β-cells is a major criterion for preventing advent of type 2 diabetes. The different natural or physiological insulin secretagogues include glucose, amino acids and fatty acids, which stimulate insulin secretion under the influence of various hormones like incretins, leptin, growth hormone, melatonin and estrogen. However, excess of nutrients lead to β-cell dysfunction and dearth of insulin involving various signal molecules like SIRT1, PPARγ, TLR4, NF-ΚB, Wnt, mTOR, inflammasomes, MCP1, EGFR, and Nrf2. A deeper insight into the functioning of these signaling molecules will also create new avenues for therapeutic interventions of curing β-cell dysfunction and death.
Part of the book: Type 2 Diabetes
TLR Signaling on Protozoan and Helminthic Parasite Infection
Toll-like receptors (TLRs), a major component of innate immune system, are expressed as membrane or cytosolic receptors on neutrophils, monocytes, macrophages, dendritic cells (DCs), B lymphocytes, Th1, Th2, and regulatory T lymphocytes. It recognizes pathogen-associated molecular patterns (PAMPs) and Toll-interleukin1 (IL-1) receptor (TIR) of various invading pathogens. Downstream signaling of TLRs activates NF-κB, which acts as a transcription factor of pro-inflammatory cytokines, chemokines, and costimulatory molecules. A balance between pro- and anti-inflammatory cytokine protects host body from infectious agents and also induces the healing process. Some of parasitic infections by protozoans and helminths such as Malaria, Leishmaniasis, Trypanosomiasis, Toxoplasmosis, Amoebiasis, Filariasis, Schistosomiasis, Ascariasis, Taeniasis, and Fasciolosis are the leading cause of death and economic loss in both developing and developed nations. Frequent exposure to parasites, immigration, refugee resettlement, increasing immunodeficiency, climate change, drug resistance, lack of vaccination, etc. are the major cause of emerging and re-emerging of the above-stated diseases. However, TLR activation by parasites could stimulate antigen presenting cells and ultimately clear the pathogens by phagocytosis. So, a better understanding of host-parasite interaction in relation to TLR signaling pathway will improve the controlling method of these pathogens in immunotherapy.
Part of the book: Toll-like Receptors