Current Medicinal Chemistry - Volume 25, Issue 18, 2018

The diagnosis of mitochondrial diseases is still challenging due to clinical and genetical heterogeneity. The development of advanced technologies including Whole-Exome- Sequencing (WES) and Whole-Genome-Sequencing (WGS) has led to improvements in genetic diagnosis. However, a reliable biomarker in serum could enhance and ease the diagnosis and indeed reduce the need for muscle biopsy. Several studies suggest Fibroblast growth factor 21 (FGF-21) as a biomarker for diagnosis in mitochondrial disorders. It is known, that in patients with mitochondrial disorders, the expression of FGF-21 gets elevated in an effort to counteract the underlying metabolic deficiency. The growth and differentiation factor 15 (GDF-15) has been described as a potential biomarker for mitochondrial diseases, too. In the present review, a literature research, using PubMed database about the reliability of FGF-21 as a biomarker for mitochondrial disorders and its comparison with GDF-15 has been performed.

For more than 40 years, the fluid mosaic model of cellular membranes has supported our vision of an inert lipid bilayer containing membrane protein receptors that are randomly hit by extracellular molecules to trigger intracellular signaling events. However, the notion that compartmentalized cholesterol- and sphingomyelin-rich membrane microdomains (known as lipid rafts) spatially arrange receptors and effectors to promote kinetically favorable interactions necessary for the signal transduction sounds much more realistic. Despite their assumed importance for the dynamics of ligand-receptor interactions, lipid rafts and biomembranes as a whole remain less explored than the other classes of biomolecules because of the higher variability and complexity of their membrane phases, which rarely provide the detailed atomic-level structural data in X-ray crystallography assays necessary for molecular modeling studies. The fact that some alkylphospholipids (e.g. edelfosine: 1-O-octadecyl-2-O-methyl-rac-glycero-3-phosphocholine) selectively induce the apoptotic death of cancer cells by recruiting Fas death receptors and the downstream signaling molecules into clusters of lipid rafts suggests these potential drug targets deserve a more in-depth investigation. Herein, we review the structure of lipid rafts, their role in apoptotic signaling pathways and their potential role as drug targets for the treatment of cancer.

Background: Endometriosis is an inflammatory gynaecological disease with an associated chronic inflammation. Interleukin(IL)-1 is one of the most important immune and proinflammatory factors, produced mainly by monocytes and macrophages. Studies indicate the role of the cytokine from IL-1 family in endometrium-related disorders, particularly in endometriosis. Methods: The information about the impact of cytokine from IL-1 cytokine family on the pathogenesis and development of endometriosis was obtained with an electronic literature search based on the PubMed and Medline databases, spanning the period of January 1950 to July 2017 and includes associated references in the published studies. Results: The impairment of the IL-1 family cytokine-network may lead to changes in the activation of immune system in the peritoneal cavity of women with endometriosis. The aberrant ectopic endometrial cell properties of adhesion, implantation and proliferation may be the result of a reduced suppressive capacity controlling the IL-1. The imbalance between IL-1α, pro-IL-1β, mature IL-1β and sIL-1R2 and sIL-1RAcP in the peritoneal fluid and serum of women with endometriosis may be linked to the ability of transforming an acute inflammation into a chronic one. Despite the fact that peritoneal macrophages secrete more antiinflammatory IL-1Ra and less proinflammatory IL-1 in the peritoneal cavity in affected women, the inflammation still develops. Conclusions: This observation clearly suggested a significant inadequacy in the specific regulatory mechanisms of IL-1 activity at the peritoneal cavity level. The imbalance between all studied cytokines in endometriosis may escalate peritoneal inflammation and, in consequence, develop endometriosis.

Background: Bile acids (BAs) are among the main components of bile. Lately, they are also considered important signaling molecules, not only by regulating their own synthesis, but also having a role in several metabolic diseases. Objective: In this review we focus on the effect of sodium deoxycholate (NaDOC), ursodeoxycholic (UDCA) and litocholic (LCA) acids and their combination upon the intestinal Ca2+ absorption. To make clear the actions of those BAs on this physiological process, an overview of current information about the mechanisms by which the intestinal Ca2+ occurs is described. Methods: The PubMed database was searched until 2017, using the keywords bile acids, NaDOC, UDCA and LCA and redox state, apoptosis, autophagy and intestinal Ca2+ absorption. Results: The modulation of redox state, apoptosis and autophagy are mechanisms that are involved in the action of BAs on intestinal Ca2+ absorption. Although the mechanisms are still not completely understood, we provide the latest knowledge regarding the effect of BAs on intestinal Ca2+ absorption. Conclusion: The response of the intestine to absorb Ca2+ is affected by BAs, but it is different according to the type and dose of BA. When there is a single administration, NaDOC has an inhibitory effect, UDCA is an stimulator whereas LCA does not have any influence. However, the combination of BAs modifies the response. Either UDCA or LCA protects the intestine against the oxidative injury caused by NaDOC by blocking the oxidative/nitrosative stress, apoptosis and autophagy.

Background: Recent findings indicate that incretin hormones and incretin-based therapies may affect the metabolism of lipoproteins, although the corresponding mechanisms are not clearly defined. Objective: To summarize the available data on the mechanisms linking incretins with the characteristics of serum lipoproteins and discuss the clinical implications of these relationships. Methods: PubMed was searched using the terms “incretins”, “GLP-1”, “GIP” and “lipids”, “dyslipidemia”, “triglycerides”, “apolipoprotein B48”. All articles published in the English language until June 2016 were assessed and the relevant information is presented here. Results: GLP-1, and therapies that increase its activity, exert a beneficial effect on lipoprotein metabolism that is translated in a reduction in the fasting and postprandial concentration of triglycerides and a small improvement in the concentration and function of HDLs. In addition, a shift towards larger, less atherogenic particles usually follows the administration of GLP-1 receptor agonists. The mechanisms that underlie these changes involve a direct effect of GLP- 1 on the hepatic and intestinal production of triglyceride-rich lipoproteins, the GLP-1 induced increase in the production and function of insulin, the activation of specific areas of central nervous system as well as the increase in the peripheral utilization of triglycerides for energy production. On the other hand, GLP-2 increases the absorption of dietary fat and the production of triglyceride-rich lipoproteins while the role of GIP on lipid metabolism remains indeterminate. Conclusion: GLP-1 and incretin-based therapies favorably affect lipid metabolism. These effects may contribute to the beneficial effects of incretin-based therapies on atherosclerosis and fatty liver disease.

Background: Diabetes mellitus type 2 (DMT2) is an endocrine disease of global proportions which is currently affecting 1 in 12 adults in the world, with still increasing prevalence. World Health Organization (WHO) declared this worldwide health problem, as an epidemic disease, to be the only non-infectious disease with such categorization. People with DMT2 are at increased risk of various complications and have shorter life expectancy. The main classes of oral antidiabetic drugs accessible today for DMT2 vary in their chemical composition, modes of action, safety profiles and tolerability. Methods: A systematic search of peer-reviewed scientific literature and public databases has been conducted. We included the most recent relevant research papers and data in respect to the focus of the present review. The quality of retrieved papers was assessed using standard tools. Results: The review highlights the chemical structural diversity of the molecules that have the common target-DMT2. So-called traditional antidiabetics as well as the newest and the least explored drugs include polypeptides and amino acid derivatives (insulin, glucagon-like peptide 1, dipeptidyl peptidase-IV inhibitors, amylin), sulfonylurea derivatives, benzylthiazolidine- 2,4-diones (peroxisome proliferator activated receptor-γ agonists/glitazones), condensed guanido core (metformin) and sugar-like molecules (α-glucosidase and sodium/ glucose co-transporter 2 inhibitors). Conclusion: As diabetes becomes a more common disease, interest in new pharmacological targets is on the rise.

Proton-pump inhibitors (PPIs), such as omeprazole, lansoprazole and rabeprazole, are used for the treatment of gastroesophageal reflux disease and peptic ulcer disease. The use of PPIs has increased, especially in older individuals, and a pharmacoepidemiological study indicated the use of PPIs peaks in people aged 80 years or older. In this population, Alzheimer's disease (AD) is a common neurological disorder and type of dementia, occurring with a frequency of approximately 10%. Currently, over 45 million people are estimated to have dementia worldwide, and it is a major cause of death in the elderly. Recent clinical studies have indicated that chronic use of PPIs can be a risk factor for increased incidence of dementia, including AD. Potential molecular mechanisms related to the pathophysiology of AD (e.g., modulation of amyloid protein processing) have also been reported in both in vitro and in vivo studies. Although the clinical implications of these results are inconclusive, a literature review of the current knowledge is important for future basic and clinical research. This review summarizes the possible mechanisms connecting the use of PPIs and the incidence of AD. Additionally, we summarize results from clinical studies to highlight the influence in humans.