Laser-Synthesized Elemental Boron Nanoparticles for Efficient Boron Neutron Capture Therapy.

Boron neutron capture therapy (BNCT) is one of the most appealing radiotherapy modalities, whose localization can be further improved by the employment of boron-containing nanoformulations, but the fabrication of biologically friendly, water-dispersible nanoparticles (NPs) with high boron content and favorable physicochemical characteristics still presents a great challenge. Here, we explore the use of elemental boron (B) NPs (BNPs) fabricated using the methods of pulsed laser ablation in liquids as sensitizers of BNCT. Depending on the conditions of laser-ablative synthesis, the used NPs were amorphous (a-BNPs) or partially crystallized (pc-BNPs) with a mean size of 20 nm or 50 nm, respectively. Both types of BNPs were functionalized with polyethylene glycol polymer to improve colloidal stability and biocompatibility. The NPs did not initiate any toxicity effects up to concentrations of 500 µg/mL, based on the results of MTT and clonogenic assay tests. The cells with BNPs incubated at a 10B concentration of 40 µg/mL were then irradiated with a thermal neutron beam for 30 min. We found that the presence of BNPs led to a radical enhancement in cancer cell death, namely a drop in colony forming capacity of SW-620 cells down to 12.6% and 1.6% for a-BNPs and pc-BNPs, respectively, while the relevant colony-forming capacity for U87 cells dropped down to 17%. The effect of cell irradiation by neutron beam uniquely was negligible under these conditions. Finally, to estimate the dose and regimes of irradiation for future BNCT in vivo tests, we studied the biodistribution of boron under intratumoral administration of BNPs in immunodeficient SCID mice and recorded excellent retention of boron in tumors. The obtained data unambiguously evidenced the effect of a neutron therapy enhancement, which can be attributed to efficient BNP-mediated generation of α-particles.

Dexamethasone Inhibits Heparan Sulfate Biosynthetic System and Decreases Heparan Sulfate Content in Orthotopic Glioblastoma Tumors in Mice.

Glioblastoma (GB) is an aggressive cancer with a high probability of recurrence, despite active chemoradiotherapy with temozolomide (TMZ) and dexamethasone (DXM). These systemic drugs affect the glycosylated components of brain tissue involved in GB development; however, their effects on heparan sulfate (HS) remain unknown. Here, we used an animal model of GB relapse in which SCID mice first received TMZ and/or DXM (simulating postoperative treatment) with a subsequent inoculation of U87 human GB cells. Control, peritumor and U87 xenograft tissues were investigated for HS content, HS biosynthetic system and glucocorticoid receptor (GR, Nr3c1). In normal and peritumor brain tissues, TMZ/DXM administration decreased HS content (5-6-fold) but did not affect HS biosynthetic system or GR expression. However, the xenograft GB tumors grown in the pre-treated animals demonstrated a number of molecular changes, despite the fact that they were not directly exposed to TMZ/DXM. The tumors from DXM pre-treated animals possessed decreased HS content (1.5-2-fold), the inhibition of HS biosynthetic system mainly due to the -3-3.5-fold down-regulation of N-deacetylase/N-sulfotransferases (Ndst1 and Ndst2) and sulfatase 2 (Sulf2) expression and a tendency toward a decreased expression of the GRalpha but not the GRbeta isoform. The GRalpha expression levels in tumors from DXM or TMZ pre-treated mice were positively correlated with the expression of a number of HS biosynthesis-involved genes (Ext1/2, Ndst1/2, Glce, Hs2st1, Hs6st1/2), unlike tumors that have grown in intact SCID mice. The obtained data show that DXM affects HS content in mouse brain tissues, and GB xenografts grown in DXM pre-treated animals demonstrate attenuated HS biosynthesis and decreased HS content.

Biodistribution of 10B in Glioma Orthotopic Xenograft Mouse Model after Injection of L-para-Boronophenylalanine and Sodium Borocaptate.

Boron neutron capture therapy (BNCT) is based on the ability of the boron-10 (10B) isotope to capture epithermal neutrons, as a result of which the isotope becomes unstable and decays into kinetically active elements that destroy cells where the nuclear reaction has occurred. The boron-carrying compounds-L-para-boronophenylalanine (BPA) and sodium mercaptoundecahydro-closo-dodecaborate (BSH)-have low toxicity and, today, are the only representatives of such compounds approved for clinical trials. For the effectiveness and safety of BNCT, a low boron content in normal tissues and substantially higher content in tumor tissue are required. This study evaluated the boron concentration in intracranial grafts of human glioma U87MG cells and normal tissues of the brain and other organs of mice at 1, 2.5 and 5 h after administration of the boron-carrying compounds. A detailed statistical analysis of the boron biodistribution dynamics was performed to find a 'window of opportunity' for BNCT. The data demonstrate variations in boron accumulation in different tissues depending on the compound used, as well as significant inter-animal variation. The protocol of administration of BPA and BSH compounds used did not allow achieving the parameters necessary for the successful course of BNCT in a glioma orthotopic xenograft mouse model.

Rational Design of Albumin Theranostic Conjugates for Gold Nanoparticles Anticancer Drugs: Where the Seed Meets the Soil?

Multifunctional gold nanoparticles (AuNPs) may serve as a scaffold to integrate diagnostic and therapeutic functions into one theranostic system, thereby simultaneously facilitating diagnosis and therapy and monitoring therapeutic responses. Herein, albumin-AuNP theranostic agents have been obtained by conjugation of an anticancer nucleotide trifluorothymidine (TFT) or a boron-neutron capture therapy drug undecahydro-closo-dodecaborate (B12H12) to bimodal human serum albumin (HSA) followed by reacting of the albumin conjugates with AuNPs. In vitro studies have revealed a stronger cytotoxicity by the AuNPs decorated with the TFT-tagged bimodal HSA than by the boronated albumin conjugates. Despite long circulation time, lack of the significant accumulation in the tumor was observed for the AuNP theranostic conjugates. Our unique labelling strategy allows for monitoring of spatial distribution of the AuNPs theranostic in vivo in real time with high sensitivity, thus reducing the number of animals required for testing and optimizing new nanosystems as chemotherapeutic agents and boron-neutron capture therapy drug candidates.

pH-triggered delivery of magnetic nanoparticles depends on tumor volume.

Nowadays there is growing recognition of the fact that biological systems have a greater impact on nanoparticle target delivery in tumors than nanoparticle design. Here we investigate the targeted delivery of Fe3O4 magnetic nanoparticles conjugated with pH-low-insertion peptide (MNP-pHLIP) on orthotopically induced MDA-MB-231 human breast carcinoma xenografts of varying volumes as a model of cancer progression. Using in vivo magnetic resonance imaging and subsequent determination of iron content in tumor samples by inductively coupled plasma atomic emission spectroscopy we found that MNP-pHLIP accumulation depends on tumor volume. Transmission electron microscopy, histological analysis and immunohistochemical staining of tumor samples suggest that blood vessel distribution is the key factor in determining the success of the accumulation of nanoparticles in tumors.

From Allostatic Load to Allostatic State-An Endogenous Sympathetic Strategy to Deal With Chronic Anxiety and Stress?

The concepts of allostatic load and overload, i. e., a dramatic increase in the allostatic load that predisposes to disease, have been extensively described in the literature. Here, we show that rats engaging in active offensive response (AOR) behavioral strategies to chronic predator scent stress (PSS) display less anxiety behavior and lower plasma cortisol levels vs. rats engaging in passive defensive response (PDR) behavioral strategies to chronic PSS. In the same chronic PSS paradigm, AOR rats also have higher lactate and lower glutamate levels in amygdala but not in control-region hippocampus vs. PDR rats. The implications of these findings for regulation of allostatic and stress responses, and post-traumatic stress disorder (PTSD) are discussed.

GC-based chemoprofile of lipophilic compounds in Altaian Ganoderma lucidum sample.

The presented data contains information about component composition of lipophilic compounds in Ganoderma lucidum fungal body sample obtained using gas chromatography and subsequent mass spectrometry.

Oncolytic effect of wild-type Newcastle disease virus isolates in cancer cell lines in vitro and in vivo on xenograft model.

Oncolyic virotherapy is one of the modern experimental techniques to treat human cancers. Here we studied the antitumor activity of wild-type Newcastle disease virus (NDV) isolates from Russian migratory birds. We showed that NDV could selectively kill malignant cells without affecting healthy cells. We evaluated the oncolytic effect of 44 NDV isolates in 4 histogenetically different human cell lines (HCT116, HeLa, A549, MCF7). The safety of the isolates was also tested in normal peripheral blood mononuclear (PBMC) cells. The viability of tumor cell lines after incubation with NDV isolates was evaluated by MTT. All cell lines, except for normal PBMC primary cells, had different degrees of susceptibility to NDV infection. Seven NDV strains had the highest oncolytic activity, and some NDV strains demonstrated oncolytic selectivity for different cell lines. In vivo, we described the intratumoral activity of NDV/Altai/pigeon/770/2011 against subcutaneous non-small cell lung carcinoma using xenograft SCID mice model. All animals were responsive to therapy. Histology confirmed therapy-induced destructive changes and growing necrotic bulk density in tumor tissue. Our findings indicate that wild-type NDV strains selectively kill tumor cells with no effect on healthy PBMC cells, and intratumoral virotherapy with NDV suppresses the subcutaneous tumor growth in SCID mice.

Hypotensive and neurometabolic effects of intragastric Reishi (Ganoderma lucidum) administration in hypertensive ISIAH rat strain.

BACKGROUND: As the standard clinically used hypotensive medicines have many undesirable side effects, there is a need for new therapeutic agents, especially ones of a natural origin. PURPOSE: One possible candidate is extract from the mushroom Reishi (Ganoderma lucidum), which is used in the treatment and prevention of many chronic diseases. STUDY DESIGN AND METHODS: To study the effectiveness of Reishi, which grows in the Altai Mountains, as an antihypertensive agent, we intragastrically administered Reishi water extract to adult male hypertensive ISIAH (inherited stress-induced arterial hypertension) rats. RESULTS: After seven weeks, Reishi therapy reduced blood pressure in experimental animals at a level comparable to that of losartan. Unlike losartan, intragastric Reishi introduction significantly increases cerebral blood flow and affects cerebral cortex metabolic patterns, shifting the balance of inhibitory and excitatory neurotransmitters toward excitation. CONCLUSION: Changes in cerebral blood flow and ratios of neurometabolites suggests Reishi has a potential nootropic effect.

Biotin-decorated anti-cancer nucleotide theranostic conjugate of human serum albumin: Where the seed meets the soil?

Human serum albumin is playing an increasing role as a drug carrier in clinical settings. Biotin molecules are often used as suitable tags in targeted anti-tumor drug delivery systems. We report on the synthesis and properties of a new multimodal theranostic conjugate based on an anti-cancer fluorinated nucleotide conjugated with a biotinylated dual-labeled albumin. Interestingly, in vitro and in vivo study revealed stronger anti-tumor activity of the non-tagged theranostic conjugate than that of the biotin-tagged conjugate, which can be explained by decreased binding of the biotin-tagged conjugate to cellular receptors. Our study sheds light on the importance of site-specific albumin modification for the design of albumin-based drugs with desirable pharmaceutical properties.

Multifunctional human serum albumin-therapeutic nucleotide conjugate with redox and pH-sensitive drug release mechanism for cancer theranostics.

We report on the synthesis and properties of a new multimodal theranostic conjugate based on an anticancer fluorinated nucleotide conjugated with a dual-labeled albumin. A fluorine-labeled homocysteine thiolactone has been used as functional handle to synthesize the fluorinated albumin and couple it with a chemotherapeutic agent 5-trifluoromethyl-2'-deoxyuridine 5'-monophosphate (pTFT). The conjugate allows for direct optical and 19F magnetic resonance cancer imaging and release of the drug upon addition of glutathione. Interestingly, the pTFT release from albumin conjugate could only be promoted by the increased acidity (pH 5.4). The in vitro study and primary in vivo investigations showed stronger antitumor activity than free pTFT.

Modulation of embryonic development due to mating with immunised males.

The modification of pre- and postnatal development conferred by immunogenic stimulation of mothers provides a population-level adaptation mechanism for non-genetic transfer of maternal experiences to progeny. However little is known about the transmission of paternal immune experiences to offspring. Here, we show that immune priming of males 3-9 days before mating affects the growth and humoral environment of developing embryos of outbred (ICR) and inbred (C57BL and BALB/c) mice. Antigenic stimulation of fathers caused a significant increase in embryonic bodyweight as measured on Day 16 of pregnancy and altered other gestation parameters, such as feto-placental ratio. Pregnant females mated with immunised males were also characterised by changes in humoral conditions as shown by measurements of blood and amniotic progesterone, testosterone and granulocyte-macrophage colony-stimulating factor (GM-CSF) cytokine concentrations. These results emphasise the role of paternal effects of immune priming on the in utero environment and fetal growth.

New effective chemically synthesized anti-smallpox compound NIOCH-14.

Antiviral activity of the new chemically synthesized compound NIOCH-14 (a derivative of tricyclodicarboxylic acid) in comparison with ST-246 (the condensed derivative of pyrroledione) was observed in experiments in vitro and in vivo using orthopoxviruses including highly pathogenic ones. After oral administration of NIOCH-14 to outbred ICR mice infected intranasally with 100 % lethal dose of ectromelia virus, it was shown that 50 % effective doses of NIOCH-14 and ST-246 did not significantly differ. The 'therapeutic window' varied from 1 day before infection to 6 days post-infection (p.i.) to achieve 100-60 % survival rate. The administration of NIOCH-14 and ST-246 to mice resulted in a significant reduction of ectromelia virus titres in organs examined as compared with the control and also reduced pathological changes in the lungs 6 days p.i. Oral administration of NIOCH-14 and ST-246 to ICR mice and marmots challenged with monkeypox virus as compared with the control resulted in a significant reduction of virus production in the lungs and the proportion of infected mice 7 days p.i. as well as the absence of disease in marmots. Significantly lower proportions of infected mice and virus production levels in the lungs as compared with the control were demonstrated in experiments after oral administration of NIOCH-14 and ST-246 to ICR mice and immunodeficient SCID mice challenged with variola virus 3 and 4 days p.i., respectively. The results obtained suggest good prospects for further study of the chemical compound NIOCH-14 to create a new smallpox drug on its basis.

Design of protein homocystamides with enhanced tumor uptake properties for (19)F magnetic resonance imaging.

Straightforward and reliable tools for in vivo imaging of tumors can benefit the studies of cancer development, as well as contribute to successful diagnosis and treatment of cancer. (19)F NMR offers an exceptional quantitative way of in vivo imaging of the infused agents because of the lack of (19)F signals from the endogenous molecules in the body. The purpose of this study is to develop molecular probes with appropriate NMR characteristics and the biocompatibility for in vivo applications using (19)F MRI. We have studied the reaction between perfluorotoluene and homocysteine thiolactone resulting in the formation of N-substituted homocysteine thiolactone derivative. It has been shown that the reaction occurs selectively at the para position. This fluorine-labeled homocysteine thiolactone has been employed for the introduction of a perfluorotoluene group as a (19)F-containing tag into human serum albumin. The modified protein has been studied in terms of its ability to aggregate and promote the formation of free radicals. By comparing the properties of N-perfluorotoluene-homocystamide of albumin with N-homocysteinylated albumin, it has been revealed that blocking of the alpha-amino group of the homocysteine residue in the fluorinated albumin conjugate inhibits the dangerous aggregation process, as well as free radical formation. A dual-labeled albumin-based molecular probe for (19)F MRI and fluorescence microscopy has been obtained by functionalizing the protein with both maleimide of a fluorescent dye and a fluorinated thiolactone derivative. The incubation of cells with this conjugate did not reveal any significant reduction in cell viability with respect to the parent albumin. The perfluorotoluene-labeled albumin has been demonstrated to act as a promising agent for in vivo (19)F MRI.

Using ICR and SCID mice as animal models for smallpox to assess antiviral drug efficacy.

The possibility of using immunocompetent ICR mice and immunodeficient SCID mice as model animals for smallpox to assess antiviral drug efficacy was investigated. Clinical signs of the disease did not appear following intranasal (i.n.) challenge of mice with strain Ind-3a of variola virus (VARV), even when using the highest possible dose of the virus (5.2 log10 p.f.u.). The 50 % infective doses (ID50) of VARV, estimated by the virus presence or absence in the lungs 3 and 4 days post-infection, were 2.7 ± 0.4 log10 p.f.u. for ICR mice and 3.5 ± 0.7 log10 p.f.u. for SCID mice. After i.n. challenge of ICR and SCID mice with VARV 30 and 50 ID50, respectively, steady reproduction of the virus occurred only in the respiratory tract (lungs and nose). Pathological inflammatory destructive changes were revealed in the respiratory tract and the primary target cells for VARV (macrophages and epithelial cells) in mice, similar to those in humans and cynomolgus macaques. The use of mice to assess antiviral efficacies of NIOCH-14 and ST-246 demonstrated the compliance of results with those described in scientific literature, which opens up the prospect of their use as an animal model for smallpox to develop anti-smallpox drugs intended for humans.