The effect of β-cyclodextrin on the Formation of Phospholipid Micelles: A Molecular Dynamics Simulation Study

Using the molecular dynamics simulation method we studied the aqueous solution ofβ-cyclodextrin and1,2-dimyristoyl-sn-glycero-3phosphocholine (DMPC) molecules. We observed that in water environment DMPCmolecules form a “core” surrounded byβ-cyclodextrins which stick to the surface of DMPC core. The developedβ-cyclodextrin shell (corona) might facilitate the transport of DMPC cluster in bioenvironment. Moreover somesmaller binary complexes, composed of only single pair ofβ-cyclodextrin and DMPC were detected. Our simulationsshowed thatβ-cyclodextrin do not influence the structure of lipid aggregates and should not negatively interferethe liposomal drug delivery systems

Impact of the Carbon Allotropes on Cholesterol Domain: MD Simulation

In recent years, immense advancement has been made in the field of nanotechnology. This emerging field will indefinitely become a critical facet of many areas including chemistry, biology, electronics and optics, and will provide unique opportunities for researchers to innovate in unimaginable ways. Nanomaterials, because of their unique mechanical, thermal, optical and electronic properties, have reshaped many segments of modern science and engineering and are increasingly impacting our society, health care, and the environment. Specifically, nanotechnology has great potential in biomedical applications, as mammal/human biology is essentially a very complex system of nano-machines. Nowadays big changes are coming from the marriage of medicine and nanotechnology - the new branch of science called nanomedicine or molecular medicine. A field of utilizing molecular assemblies at the nano-scale of about 100 nm or less for novel and alternative diagnostics and therapeutics, in incredible selectivity and accuracy not achievable through conventional means. One would hope that with the future development of nanomedicine, we will be able to think of today's incurable diseases as curable tomorrow, by looking at a problem at its molecular or even atomic levels and apply medical intervention at the molecular scale. [frag

The impact of a carbon nanotube on the cholesterol domain localized on a protein surface

The influence of a single walled carbon nanotube on the structure of a cholesterol cluster (domain) developed over the surface of the endothelial protein 1LQV has been investigated using the classical molecular dynamics (MD) simulation technique. We have observed a substantial impact of carbon nanotube on the arrangement of the cholesterol domain. The carbon nanotube can drag out cholesterol molecules, remarkable reducing the volume of the domain settled down on the protein.Comment: 17 pages, 8 figure

The effect of NaCl on the level of reduced sulfur compounds in rat liver : implications for blood pressure increase

Background: It is commonly known that excessive salt intake is a risk factor of hypertension. Currently, there is an increasing interest in reduced reactive sulfur species (RSS), mainly H2S and sulfane sulfur (SS) as new gasotransmitters showing vasorelaxant properties. The aim of the present study was to determine the effect of repeated administration of low sodium chloride dose included in physiological saline on blood pressure, on the level of RSS and activity of enzymes involved in their biosynthesis in the rat.Methods: Two separate experiments were carried out on male Wistar rats: one with intravenous injections of saline and the second one with intraperitoneal saline injections. Blood pressure was measured during the experiment. The level of RSS and other biochemical assays were conducted in the rat liver, because of an intense cysteine metabolism to RSS in this organ.Results: Intravenous administration of saline induced a significant increase in systolic blood pressure while intraperitoneal injections showed only a tendency towards increasing blood pressure. The RSS (H2S and SS) level as well as the activity of the main enzyme responsible for their production in the liver of animals after iv saline injections were decreased. Animals injected with physiological saline by ip route did not reveal any statistically significant differences in SS, H2S, and activities of sulfurtransferases, although a tendency to decrease in the RSS was observed.Conclusions: The repeated iv saline injection induced a slight hypertension accompanied by disturbances in anaerobic cysteine metabolism in the rat liver

Lipoic Acid as a Possible Pharmacological Source of Hydrogen Sulfide/Sulfane Sulfur

The aim of the present study was to verify whether lipoic acid (LA) itself is a source of H2S and sulfane sulfur. It was investigated in vitro non-enzymatically and enzymatically (in the presence of rat tissue homogenate). The results indicate that both H2S and sulfane sulfur are formed from LA non-enzymatically in the presence of environmental light. These results suggest that H2S is the first product of non-enzymatic light-dependent decomposition of LA that is, probably, next oxidized to sulfane sulfur-containing compound(s). The study performed in the presence of rat liver and kidney homogenate revealed an increase of H2S level in samples containing LA and its reduced form dihydrolipoic acid (DHLA). It was accompanied by a decrease in sulfane sulfur level. It seems that, in these conditions, DHLA acts as a reducing agent that releases H2S from an endogenous pool of sulfane sulfur compounds present in tissues. Simultaneously, it means that exogenous LA cannot be a direct donor of H2S/sulfane sulfur in animal tissues. The present study is an initial approach to the question whether LA itself is a donor of H2S/sulfane sulfur