Nanoparticle-mediated gene delivery to tumour neovasculature

The alpha(v)beta(3) integrin is a potential pharmacological target for anti-angiogenic therapy. A recent report describes the use of alpha(v)beta(3)-targeted nanoparticles to deliver a gene to tumour vasculature selectively. This resulted in substantial tumour regression in several experimental mouse tumour models. Hence, this approach has great potential for the treatment of human cancer.     

Supplementation of maturation medium with CoQ10 enhances developmental competence of ovine oocytes through improvement of mitochondrial function

In vitro maturation (IVM) can impair the balance between antioxidant capacity and oxidative stress, and jeopardize embryo development by increasing oxidative stress, reducing energy metabolism, and causing improper meiotic segregation. Balancing the energy production and reduction of oxidative stress can be achieved by supplementation with coenzyme Q10 (CoQ10), an electron transporter in the mitochondrial inner membrane. To improve the in vitro production of ovine embryos, we studied the effect of CoQ10 supplementation during the maturation of sheep oocytes. A minimum of 100 cumulus‐oocyte complexes (COCs) were matured in the presence of 15, 30, or 50 μM CoQ10 in three to five replicates; next, in vitro fertilization and culture in a subset of oocytes were done. Our data revealed that compared to control oocytes or other concentrations of CoQ10, supplementation with 30 µM CoQ10 resulted in a significant increase in blastocyst formation and hatching rates, improved the distribution, relative mass and potential membrane of mitochondria, decreased the levels of reactive oxygen species and glutathione and lessened the percentage of oocytes with misaligned chromosomes after spindle assembly. The relative expression levels of apoptosis markers CASPASE3 and BAX were significantly reduced in CoQ10‐treated oocytes and cumulus cells whereas the relative expression level of GDF9, an oocyte‐specific growth factor, significantly increased. In conclusion, supplementation with CoQ10 improves the quality of COCs and the subsequent developmental competence of the embryo.     

Biomembrane Fabrication by the Solvent-assisted Lipid Bilayer (SALB) Method

In order to mimic cell membranes, the supported lipid bilayer (SLB) is an attractive platform which enables in vitro investigation of membrane-related processes while conferring biocompatibility and biofunctionality to solid substrates. The spontaneous adsorption and rupture of phospholipid vesicles is the most commonly used method to form SLBs. However, under physiological conditions, vesicle fusion (VF) is limited to only a subset of lipid compositions and solid supports. Here, we describe a one-step general procedure called the solvent-assisted lipid bilayer (SALB) formation method in order to form SLBs which does not require vesicles. The SALB method involves the deposition of lipid molecules onto a solid surface in the presence of water-miscible organic solvents (e.g., isopropanol) and subsequent solvent-exchange with aqueous buffer solution in order to trigger SLB formation. The continuous solvent exchange step enables application of the method in a flow-through configuration suitable for monitoring bilayer formation and subsequent alterations using a wide range of surface-sensitive biosensors. The SALB method can be used to fabricate SLBs on a wide range of hydrophilic solid surfaces, including those which are intractable to vesicle fusion. In addition, it enables fabrication of SLBs composed of lipid compositions which cannot be prepared using the vesicle fusion method. Herein, we compare results obtained with the SALB and conventional vesicle fusion methods on two illustrative hydrophilic surfaces, silicon dioxide and gold. To optimize the experimental conditions for preparation of high quality bilayers prepared via the SALB method, the effect of various parameters, including the type of organic solvent in the deposition step, the rate of solvent exchange, and the lipid concentration is discussed along with troubleshooting tips. Formation of supported membranes containing high fractions of cholesterol is also demonstrated with the SALB method, highlighting the technical capabilities of the SALB technique for a wide range of membrane configurations.     

The Impacts of Prepared Plasma-Activated Medium (PAM) Combined with Doxorubicin on the Viability of MCF-7 Breast Cancer Cells: A New Cancer Treatment Strategy

Background:For many years, the chemotherapeutic agent doxorubicin (DOX) has been used to treat various cancers; however, DOX initiates several critical adverse effects. Many studies have reported that non-thermal atmospheric pressure plasma can provide novel, but challenging, treatment strategies for cancer patients. To date, tissues and cells have been treated with plasma-activated medium (PAM) as a practical therapy. Consequently, due to the harmful adverse effects of DOX, we were motivated to elucidate the impact of PAM in the presence of DOX on MCF-7 cell proliferation.Methods:MTT assay, N-acetyl-L-cysteine (NAC) assay, and flow cytometry analysis were utilized in this research.Results:The results demonstrated that 0.45 µM DOX combined with 3-min PAM significantly induced apoptosis (p< 0.01) through intracellular ROS generation in MCF-7 when compared with 0.45 µM DOX alone or 3-min PAM alone. In contrast, after treatment with 0.45 µM DOX plus 4-min PAM, cell necrosis was increased. Hence, DOX combined with 4-min PAM has cytotoxic effects with different mechanisms than 4-min PAM alone, in which the number of apoptotic cells increases.Conclusion:Although further investigations are crucial, low doses of DOX plus 3-min PAM could be a promising strategy for cancer therapy. The findings from this research may offer advantageous and innovative clinical strategies for cancer therapy using PAM.Key Words: Apoptosis, Breast cancer lymphedema, Doxorubicin, Plasma-activated medium (PAM), Necrosis     

Novel filamentous spore-forming iron bacteria causes bulking in activated sludge

Several Gram-positive iron bacteria were isolated from bulking sludge. They were filamentous and had false branching. They had sheaths with iron deposits and formed spores on modified sucrose casitone yeast extract agar. They did not grow on influsion agar for longer than 1 month but could withstand 80°C for 1 h on the same medium. Adding them to sewage before aeration increased the biochemical oxygen demand of waste water and caused poor settling properties of activated sludges. They were the predominant filamentous micro-organisms in bulking activated sludges. At present, these strains cannot be assigned to recognized taxa of Bacillus spp. or sheathed iron bacteria.     

Evaluation of some genes and proteins involved in apoptosis on human chronic myeloid leukemia cells (K562 cells) by datura innoxia leaves aqueous extract

Abstract

Datura innoxia (D. innoxia) has an extensive usage in traditional medicine and can also be used for intervention therapy in order to treat cancer. Despite of accomplishing some researches on D. innoxia mechanism, still our knowledge is very little about exact D. innoxia apoptotic mechanism on human chronic myeloid leukemia cells (K562 cells). This study purpose was to clarify the molecular mechanism of apoptosis, which was mediated by D. innoxia leaves aqueous extract in K562 cells. MTT assay and flow cytometry was applied in order to assess the viability and apoptosis induction of K562 cells and normal human lymphoid B cells in the D. innoxia presence. Finally, the expression of the apoptotic related genes (p53, BAX, BCL2, Caspases 3, 6, 7 and 9) were evaluated using quantitative Real-Time PCR. Western blot analysis was applied for assessing the protein expression. MTT results indicated that D. innoxia could inhibit the viability of K562 cells in a dose- and time-dependent manner. In parallel, D. innoxia inhibitory effect on normal human lymphoid B cells was lower in comparison with its effect on K562 cells at the same concentrations and same incubation time. Apoptosis induction in K562 cells after D. innoxia exposure was determined by flow cytometry. Apoptosis was activated by D. innoxia in K562 cells throughout increasing the expression of P53, BAX/BCL2 ratio, caspase 9, 3, 6, 7. Western blot analysis demonstrated significant increase in cleaved PARP-1 and cleaved caspase 3 in treated K562 cells with high D. innoxia leaves aqueous extract concentration. D. innoxia leaves trigger apoptosis in K562 cells throughout intrinsic apoptotic pathway.

Communicated by Ramaswamy H. Sarma     

Differential properties of organ-specific serum opsonins for liver and spleen macrophages

Earlier we reported that serum contains organ-specific opsonins which selectively enhance recognition of liposomes by macrophages in the specific organs of the reticuloendothelial system (Moghimi, S.M. and Patel, H.M. (1988) FEBS Lett. 233, 143-147). The results presented here describe the properties of these organ-specific opsonins which differentiate between liver-specific and spleen-specific opsonins responsible for the enhancement of phagocytosis of liposomes by Kupffer cells and spleen macrophage, respectively. Liver-specific opsonin is a heat-stable macromolecule which on heating or on freezing and thawing exhibits enhanced opsonic activity. Serum also contains a dialysable factor which inhibits its opsonic activity. On the other hand, the spleen-specific opsonin is a heat-labile macromolecule which is sensitive to freezing and thawing and requires a dialysable serum co-factor for its optimum opsonic activity on spleen macrophages. Removal of this factor from serum brings about an irreversible conformational change in the opsonin. Evidence suggests that the spleen-specific opsonin may be composed of more than one different opsonin molecule. It is suggested that the serum factor(s) that inhibits liver-specific opsonic activity and enhances the spleen-specific activity may not be the same molecule, but in both the cases the factor(s) may mediate its function by modifying the process of the opsonisation of liposomes or by influencing the interaction of the opsonised liposomes with the respective cells. We propose that purification of the organ-specific opsonins may provide an opportunity to target drug carriers selectively to a specific organ of the reticuloendothelial system, and help us to evaluate their role in the altered opsonin states known to exist in certain diseases.