Horizontal Gene Transfer: From Evolutionary Flexibility to Disease Progression.

Flexibility in the exchange of genetic material takes place between different organisms of the same or different species. This phenomenon is known to play a key role in the genetic, physiological, and ecological performance of the host. Exchange of genetic materials can cause both beneficial and/or adverse biological consequences. Horizontal gene transfer (HGT) or lateral gene transfer (LGT) as a general mechanism leads to biodiversity and biological innovations in nature. HGT mediators are one of the genetic engineering tools used for selective introduction of desired changes in the genome for gene/cell therapy purposes. HGT, however, is crucial in development, emergence, and recurrence of various human-related diseases, such as cancer, genetic-, metabolic-, and neurodegenerative disorders and can negatively affect the therapeutic outcome by promoting resistant forms or disrupting the performance of genome editing toolkits. Because of the importance of HGT and its vital physio- and pathological roles, here the variety of HGT mechanisms are reviewed, ranging from extracellular vesicles (EVs) and nanotubes in prokaryotes to cell-free DNA and apoptotic bodies in eukaryotes. Next, we argue that HGT plays a role both in the development of useful features and in pathological states associated with emerging and recurrent forms of the disease. A better understanding of the different HGT mediators and their genome-altering effects/potentials may pave the way for the development of more effective therapeutic and diagnostic regimes.

Implications of resistin in type 2 diabetes mellitus and coronary artery disease: Impairing insulin function and inducing pro-inflammatory cytokines.

Diabetes mellitus is a metabolic and chronic disorder, which is very common all over the world. Many genetic and nongenetic factors are involved in the development of type 2 diabetes mellitus (T2DM). Meanwhile, the resistin gene is an important candidate in the pathogenesis of this complex condition. High levels of transcription of the resistin gene are associated with inflammation, insulin resistance, initiation and development of T2DM and atherosclerosis progression through induction of secretion of bioactive materials from adipocytes. Releasing adipose tissue-derived inflammatory cytokines is associated with inflammatory processes activation, which causes inhibition of insulin action via interference with insulin signaling, such that these disorders can contribute to insulin resistance. With the direct effect of resistin and other inflammatory mediators on vascular endothelial cells and arterial walls, the expression of cell adhesion molecules is increased. This process can lead to atherosclerosis and will result in coronary artery disease (CAD). In this review, we will explore the effects of resistin on inflammation and insulin resistance that may lead to type 2 diabetes and CAD.