For potential use as a diagnostic test, morphological changes in the lung tissue of rats after inhalationof e-cigarette liquid based on polypropylene glycol and glycerol were studied ex vivo and in vivo. Lungs of Wistar rats placed for 1 hour in ecigarette liquid were used in the ex vivo study. The in vivo study was performed on 12 mature male Wistar rats. The animals were divided into two groups - experimental and control, 6 rats in each. Rats of the experimental group were placed in aerosol administration chamber and exposed to an aerosol of nicotine-free liquid for electronic cigarettes. Rats of the control group were intact. The animals were removed from the experiment one hour after inhalation, lung tissue samples were examined ex vivo using optical coherence tomography (OCT) and lung tissue spectroscopy. After manipulations, lung samples were fixed in 10% formalin solution and embedded in paraffin. Then histological sections were made according to the conventional methods, followed by hematoxylin and eosin staining. Comparative analysis of B-scans ex vivo of lung tissue samples placed in e-cigarette liquid and control samples showed the presence of a luminescent effect on lung tissue in the studied solution, as alveoli are filled with the solution and scattering is reduced. The structure of the tissue differs from the control samples. B-scan in vivo studies are characterized by the presence of voids of rather large size. Histological examination of ex vivo and in vivo specimens noted morphological changes in lung tissue structure corresponding to the changes observed in OCT.
For photodynamic therapy (PDT), galactose – Lutetium (Lu)-phthalocyanine, as a novel photosensitizer, was administered by intratumoral injection in 8 outbred albino male mice with inoculated hepatoma in a dose of 2 mg/kg. Then, tumors were irradiated through the skin by 670 nm-diode laser source with irradiation dose 200 J /cm2 applied for 1000 sec. The withdrawal of the animals from the experiment and sampling of tissues for morphological study were performed before (n=4) and 72 hrs after PDT (n=4). Tissue of the tumor was taken for morphological examination and fixed in 10% formalin. Serial paraffin sections were stained with hematoxylin-eosin and with the use of immunohistochemical staining with antibodies to proliferation marker Ki-67 and apoptotic marker BAX (Abcam, UK). 3 days after PDT with galactose- Lu-phthalocyanine, pronounced necrotic changes and inflammation reaction were observed in central tumor area, necrosis fields occupied up to 80% of the area. The dystrophic changes, reduction of proliferation degree and development of apoptosis in tumor cells were observed on tumor periphery. The decreased expression of proliferation marker Ki-67 and the increased expression of apoptotic marker BAX were noted in tumor cells after PDT.
The goal of our research was to assess the vascularization degree of tumor to predict the efficiency of plasmonic photothermal therapy (PPT) and photodynamic therapy (PDT) in tumor-bearing rats. Before any treatment, 3D Doppler ultrasound imaging was used for assessment of the vascularization degree of transplanted rat cholangiocarcinoma. For PPT, the gold nanorods with aspect ratio of 4:1, functionalized with thiolated polyethylene glycol, were used. After multiple fractional intravenous (IV) injections in rats with cholangiocarcinoma, the tumours were irradiated through the skin by an 808-nm NIR diode laser at a power density of 2.3 W/cm2 for 15 min. For PDT, galactose – Luphthalocyanine, as a photosensitizer, was applied by intratumoural injection, in a dose of 2 mg/kg. Then, tumors were irradiated through the skin by 670 nm-diode laser source with power density 200 mW/cm2 applied for 1000 sec in three non-overlapping zones covering whole tumour surface to obtain a total irradiation dose of 200 J/cm2 for each lesion. The withdrawal of the animals from the experiment and sampling of tissues for morphological study were performed before and 72 hrs after PPT and PDT. The vascular microdensity in tumors was assessed on histological sections as vessel counts or vessel area per unit of assessed tumor area. It was shown that efficiency of PPT and PDT therapy was mostly due to the sufficient accumulation of photothermosensitizers in the tumor, therefore preliminary assessment of tumor vascularization degree was necessary before starting a therapy.
Our previous study has revealed that specific ornithosis antigens extracted from Сhlamydia psittaci (CP) could possess some modulatory activity on the growth of malignant solid tumors in Wistar rats. Here, in the same model we studied dose-dependent dynamics of tumor growth under the influence of CP antigen derived from CP AMK-16 strain, in doses ranged from 0.025 mg/kg to 1.25 mg/kg given as a single subcutaneous injection. Velocity of tumor growth has been estimated by t-LASCA technique.
The paper presents the investigation of change of optical properties of the rat transplanted cholangiocarcinoma doped with gold nanorods after laser-induced plasmon-resonant photothermal treatment (PPT). 72, 48 and 24 hours before the experiment the animals were injected with the suspension of gold nanorods intravenously. For irradiation a diode laser with wavelength 808 nm was used. After the irradiation the tumors and surrounding tissues were removed and sliced. The samples studied were: skin, subcutaneous connective tissue, tumor capsule, top, center, and bottom part of tumor. Spectra of total transmittance and diffuse reflectance of the samples were measured in the wavelength range 350-2250 nm. Absorption and reduced scattering coefficients of the tumor tissues were calculated with inverse adding-doubling method. The results of the experiment were compared with result of investigation of the control tissues without gold nanorods injection and PPT. A decrease in the absorption coefficient of tumor layers in the water absorption bands was obtained, which indicated tissue dehydration during PPT. A decrease in the reduced scattering coefficient of tumor layers indicated an increase in the size of scatterers and an increase in their ordering. Changes in the optical parameters of the skin and subcutaneous layer were insignificant, which indicated a weak thermal damage.
The study of blood microcirculation is one of the most important problems of the medicine. This is caused by the fact that many diseases, such as cardio-vascular diseases, atherosclerosis, diabetes, chronic venous insufficiency, oncology diseases, cause functional and morphological changes of microcirculation of blood flow. The results of experimental study of changes of blood microcirculation of pancreas in rats with diabetes measured by using Laser Speckle Contrast Imaging (LSCI) at application of optical clearing agents are presented. Laser speckle contrast techniques are based on the spatial and temporal statistics of the speckle pattern, calculating of contrast of time-averaged dynamic speckles in dependence on the exposure time at the registration of the speckle-modulated images. In research, 38 Wistar rats weighing 300-500 g were used. Alloxan induced animal model and streptozotocin model of diabetes was explored. The influence of solution of glycerol, Omnipaque®-300 was investigated. Application of 70%-aqueous glycerol solution demonstrates 50%-decrease of blood flow velocity in the group of aloxan diabetic animals, to 10th min blood flow velocity was completely restored. In a group of animals with streptozotocin diabetes, the blood flow rate decreased by 54%, by 10 minutes the speed did not reach the initial value. Blood flow in the control group almost stopped, to 10 min has not recovered. Application of Omnipaque®-300 demonstrates 65%-increase of blood flow in the group of alloxan diabetic animals and an increase of bloode flow in the first 2 minutes of applying the solution by 45%. In both cases to 10th min, blood flow velocity was completely restored. Blood flow in the control group did not show any noticeable changes.
The aim of the study is investigation of morphological features of the testicles of rat newborns with different models of intrauterine hypoxia. Fifteen white outbred female rats aged from 4 to 10 months with a weight of 200 ± 30 g were used. Laboratory animals were divided into 3 experimental groups, 5 rats in each. The first group was subjected to a hypoxic hypoxia during pregnancy (21 days). The hypoxia was simulated in accordance with the method of N.N. Karkishchenko (2010). The second group was subjected to a hemic hypoxia during the second and third weeks of pregnancy, in accordance with the methodology of L.M. Sosedova (2012). The third (control) group was not exposed to any treatment during the pregnancy. After delivery, the newborn rat pups were subjected to the measurements of oxygenation degree using the methods of reflectance spectroscopy, then the animals were withdrawn from the experiment; and a morphological study of the testicle tissues was performed. Histological examination of the tissues of the testicles of newborn rats showed signs of impaired blood circulation, dystrophic and necrobiotic changes in the parenchyma.
Two models of diabetes, such as alloxan and streptozotocin, were used in the study to verify the influence of both on the optical properties and molecular permeability of skin ex vivo. Kinetics of collimated transmittance of control and diabetic skin samples immersed in aqueous 70%-glycerol solution was measured and then processed for estimation of diffusion coefficient of glycerol in skin. As a result, the slower glycerol diffusion rate was observed for both models of diabetes.
In this report, the influence of C. psittaci (CP) antigens on the process of a development of a malignant solid tumor in the inbred Wistar white rats in experimental conditions has been successfully studied. Velocity of growing of a tumor has been estimated by s-LASCA technique. Measurement of statement of a tumor has been performed daily after each of three serial injections of the CP specific ornithosis antigen derived from two different CP strains, the Rostinovo-70 and the АМК. Single injection solutions were administered in a volume of 1 ml. We found, that both antigens could initiate the marked decrease of the growth of malignant tumors in the animal model used.
The results of an experimental study of changes in the microcirculation of subcutaneous blood flow in a malignant tumor using laser speckle contrast imaging (LSCI) using an optical clearing agent of 70% glycerol solution are presented. In this study, for hemodynamic monitoring we used the speckle contrast method, which is one of the laser speckle imaging methods. This method is based on calculation of contrast of time-averaged dynamic speckles in dependence on the exposure time at the registration of the speckle-modulated images. Analysis of change of hemodynamic was carried out depending on the stage of development of pathologyIn research, we used 15 white laboratory rats Wistar weighing 300-500 g. A tumor was inoculated in laboratory rats by subcutaneous injection of 0.5 ml of a 25% tumor suspension into the area of the shoulder blades in a Hanks solution strain of PC1 alveolar liver cancer. Laboratory animals were divided into three groups, the first included healthy animals, the second - animals with an inoculated tumor 14 days after injection and the third - animals with an inoculated tumor 28 days after injection. It was found that the blood flow rate in pathological group No. 2 was reduced by 25% relative to control measurements of group No. 1, in pathological group No. 3 increased by 20% relative to control measurements. Also, the results showed that the use of a 70% glycerol solution reduced the blood flow velocity in the control group by about 2 times. Moreover, in pathological groups, the effect of the solution on the blood flow is more pronounced, in the group, the measurements on which were carried out 14 days after the inoculation of the tumor, the blood flow rate decreased by 2.8 times, after 28 days - by 4 times. The results obtained in the study of disorders of the microcirculation of the subcutaneous blood flow under the conditions of the development of a malignant tumor show that the development of diseases in animals causes changes in the microcirculatory system, and the use of optical clearing agents demonstrates changes in vascular permeability under conditions of the development of pathologies.
Application of many optical methods, such as photoacoustics, optical coherent tomography, and terahertz spectroscopy, for tissue imaging and disease diagnostics is limited due to small probing depth caused by strong scattering and absorption in tissues [1, 2]. It is possible to increase the efficiency of optical techniques by using tissue optical clearing (TOC), which allows one to control tissue optical properties by exposing tissue to biocompatible liquids - optical clearing agents (OCAs). When exposed to an OCA with hyperosmotic properties, such as glycerol or highly concentrated glucose solution, it is possible to achieve a considerable decrease of tissue scattering within the entire spectral range and absorption on the water bands due to refractive index matching phenomenon and dehydration of the tissue, and therefore to get a significant increase of the optical and THz wave transmittance [1-3]. In vitro studies were performed on laboratory rats of the Vistar strain (sexually mature females weighing 300–400 g were used). The animals were inoculated with the tumor cells by subcutaneous injection into the area of the scapulae. Studies were conducted in 28 days after injection. The weight and thickness of the samples were measured before and after optical clearing by using a micrometer with an accuracy of ±0.001 mm and an analytical balance (Scientech, SA210, USA) with an accuracy of ±1 mg. The samples of the area 1.5*1.5 cm2 were placed in a closed sealed container, to which was added 2 ml of OCA. 70% glycerol solution, 40% glucose solution and 50% fructose in a 30% alcohol solution were used with the addition of saline as an OCA. The transmission spectrum of glycerol in the frequency range of 0.05–1.0 THz was measured by using the terahertz (THz) time-domain spectrometer. Measurements of the refractive index of OCA were carried out before the start of the experiment and every 5 minutes after placing the skin sample in the solution with OCA for 15 minutes, then every 10 minutes for another 45 minutes. It was found that the effectiveness of optical clearing of the skin over the tumor is higher compared to healthy skin. A good correlation was shown between the kinetics of the sample mass and THz absorption and refraction. An assessment of skin dehydration also showed that the concentration of water extracted from the skin above the tumor is greater compared to healthy. It is especially important that enhancing the image contrast due to dehydration and TOC in the pathology area is extremely significant in diagnosing precancerous conditions and treating early stages of tumor, due to the possibility of selective increase of the scattering contrast of cell nuclei relative to surrounding cytoplasm and interstitial fluid and thus following their size and internal rearrangements [5].
The new generations of photoactive compounds, which are derivatives of already well-established groups of photosensitizers, together with the modern light sources in the spectral region of their activation and in the PDT window range, are emerging as a reliable phototherapy approach for tumour treatment with higher efficiency. The substitution of a highly hydrophobic phthalocyanine with galactose units could improve the solubility and to decrease significant aggregation in polar solvents.
The control group of rats with transplanted cholangiocarcinoma without any treatment was used for comparison of PDT effectiveness. In the second group the white outbred male rats with cholangiocarcinoma lesions were treated using Zn-phthalocyanine, as a typical representative of phthalocyanine photosensitizers with known photodynamic properties and the third group of animals was treated with galactose – Lu-phthalocyanine, as a novel derivative from the same family with two specific differences – presence of galactose and replacing of Zn(II) with Lu(III) ion. To compare the PDT effectiveness of both compounds the same drug doses were applied - 2 mg/kg, applied by intratumoural injection. Diode laser source at 670 nm, on 50 mW output power with power density applied 200 mW/cm2 was applied for 1000 sec to obtain total irradiation dose of 200 J/cm2 for each lesion.
3 days after treatment, the animals were withdrawn from the experiment. Tissue from the central zone and periphery of the tumor was taken for morphological examination and fixed in 10% formalin. Serial paraffin sections were stained with hematoxilin-eosin and by immunohistochemical staining with antibodies to proliferation marker Ki-67 and apoptosis marker BAX. After photodynamic therapy, pronounced necrobiotic changes in combination with an inflammatory reaction were developed at the central zone of tumors. The dystrophic changes, reduction of proliferation and development of apoptosis in tumor cells were observed on tumor periphery as well.
The aim of work was to study the characteristics of uteroplacental blood flow in pregnant rats, tissue oxygenation and the morphological features of the main internal organs (heart, liver, kidneys) of newborns during chronic intrauterine hypoxia. The rats (8 animals) were divided into 2 experimental groups. The first (hypoxia) group was subjected to hypoxia throughout pregnancy (21 days). The second (control) group was not exposed to any effect throughout the pregnancy. On the 20th day of gestation in both groups, a Doppler ultrasound study of uterine-fetal blood flow and measurement of the placenta was performed. Newborn rat pups of the first day of life were subjected to oxygenation degree measurement. After delivery, the number of rats in the litter was counted and their body weight was measured. After the measurements the laboratory animals were withdrawn from the experiments and morphological study of their internal organs was performed. The studies have shown a clear relationship between the characteristics of uterine blood flow and the presence or absence of hypoxia. In chronic hypoxia, there were low rates of arterial blood flow, an increase in the peripheral resistance of uterine vessels. All this indicates the defective formation of the placenta and impaired blood flow with the development of placental insufficiency. It was also found that hypoxia in the antenatal period adversely affects the number and somatometric indicators of newborn rats in the offspring. Histological examination of the tissues of the heart, liver and kidney of newborn rat pups showed signs of impaired blood circulation, dystrophic and necrobiotic changes in the parenchyma.
The study offers a possibility to use such biocompatible chemical as glycerol as a biomarker for early diagnostics of diabetes mellitus complications, in particular, for assessing the degree of myocardial lesion evidence by the stage of skin glycation during diabetes development and treatment. The study was aimed to find the difference in glycerol permeability through rat soft tissues of control and diabetic groups in order to show the possibility of glycerol usage as a biomarker of diabetes impact on different organs. The investigation presents transition the experimental studies from ex vivo to in vivo conditions.
The study of blood microcirculation is one of the most important problems of the medicine. This is caused by the fact that many diseases, such as cardio-vascular diseases, atherosclerosis, diabetes, chronic venous insufficiency, oncology diseases, cause functional and morphological changes of microcirculation of blood flow. The results of experimental study of changes of blood microcirculation of pancreas in rats with diabetes measured by using Laser Speckle Contrast Imaging (LSCI) at application of optical clearing agents are presented. Laser speckle contrast techniques are based on the spatial and temporal statistics of the speckle pattern, calculating of contrast of time-averaged dynamic speckles in dependence on the exposure time at the registration of the speckle-modulated images. In research, 28 Wistar rats weighing 300-500 g were used. Alloxan induced animal model of diabetes was explored. The influence of solution of glycerol, PEG-300 was investigated. Application of 70%-aqueous glycerol solution demonstrates 50%-decrease of blood flow velocity in the group of diabetic animals, to 10th min blood flow velocity was completely restored. Blood flow in the control group almost stopped, to 10 min has not recovered. Application of solution of PEG-300 demonstrates 25%- decrease of blood flow in the group of diabetic animals. Blood flow in the control group show 65%-decrease of blood flow. The results obtained at the study of blood microcirculation disorders of pancreas in diabetes show that diseases development in animals causes changes in the microcirculatory system and application of optical clearing agents demonstrates changes in vascular permeability in conditions of development of pathologies.
This study focuses on the effect of the flavonoid-containing Gratiola officinalis L. extract with antitumor activity on the intensity of peroxidation and the content of vitamin E in the blood serum of animals with transplanted liver cancer PC-1. Intramuscular and oral administrations of the Gratiola officinalis extract in a dose of 110 mg/kg reduce MDA concentration (more than 20 times) and lipid hydroperoxide (more than 1.5 times) in rats with transplanted tumors. This effect leads to decrease in intensity of lipid peroxidation processes in animals. The Gratiola officinalis extract administration increases the vitamin E concentration (more than 1.3 times) in the serum of rats. This result enables to suggest that the extract of Gratiola officinalis contains the tocopherols. Thus, the study of mechanisms of the Gratiola officinalis extract influence on the activity of peroxidation processes and on the activation of the antioxidant system is promising.
The paper presents the investigation of change of tumor optical properties of the rat tumor doped by gold nanoparticles after laser-induced plasmon-resonant photothermal treatment. To obtain the model tumors the rats have been implanted by suspension of alveolar kidney cancer cells. An hour before the experiment the animals have been injected by the suspension of gold nanorods intratumorally. For irradiation a diode laser with wavelength 808 nm has been used. After the irradiation the tumor has been removed and sliced. Spectra of total and collimated transmission and diffuse reflectance of the samples of different layers of the tumors have been measured in the wavelength range 350-2500 nm. Absorption, scattering, reduced scattering coefficients and scattering anisotropy factor of tumor tissues have been calculated with inverse adding-doubling method. The results of the experiment have shown that after doping the tumor tissue by the plasmon resonant nanoparticles and NIR laser irradiating, there is the decreases of absorption as well as scattering properties of the tumor and surrounding tissues. However, despite the sufficiently high temperature on the surface (about 80°C), the changes in the center of the tumor are insignificant.
Here we show the interaction between the meningeal lymphatic system and the blood-brain barrier (BBB) function. In normal state, the meningeal lymphatic vessels are invisible on optical coherent tomography (OCT), while during the opening of the BBB, meningeal lymphatic vessels are clearly visualized by OCT in the area of cerebral venous sinuses. These results give a significant impulse in the new application of OCT for the study of physiology of meningeal lymphatic system as well as sheds light on novel strategies in the prognosis of the opening of the BBB related with many central nervous system diseases, such as stroke, brain trauma, Alzheimers disease, etc.
We report on plasmonic photothermal therapy of rats with inoculated cholangiocarcinoma through the intratumoral injection of PEG-coated gold nanorods followed by CW laser light irradiation. The length and diameter of gold nanorods were 41±8 nm and 10±2 nm, respectively; the particle mass-volume concentration was 400 μg/mL, which corresponds to the optical density of 20 at the wavelength 808 nm. The tumor-bearing rats were randomly divided into three groups: (1) without any treatment (control); (2) with only laser irradiation of tumor; (3) with intratumoral administration of gold nanorods and laser irradiation of tumors. An hour before laser irradiation, the animals were injected intratumorally with gold nanorod solutions in the amount of 30% of the tumor volume. The infrared 808-nm laser with power density of 2.3 W/cm2 was used for plasmonic photothermal therapy (PTT). The withdraw of animals from the experiment was performed 24 h after laser exposure. The content of lipid peroxidation products and molecular markers of inflammation (TNF-α, IGF-1, VEGF-C) was determined by ELISA test in serum of rats. The standard histological techniques with hematoxylin and eosin staining were used for morphological examination of tumor tissues. It was revealed that the significant necrotic changes were noted in tumor tissue after plasmonic photothermal therapy, which were accompanied by formation of inflammatory reaction with release of proinflammatory cytokines and lipid peroxidation products into the bloodstream
Delivery and spatial localization of upconversion luminescent microparticles [Y2O3:Yb, Er] (mean size ∼1.6 μm) and quantum dots (QDs) (CuInS2/ZnS nanoparticles coated with polyethylene glycol-based amphiphilic polymer, mean size ∼20 nm) inside rat skin was studied in vivo using a multimodal optical imaging approach. The particles were embedded into the skin dermis to the depth from 300 to 500 μm through microchannels performed by fractional laser microablation. Low-frequency ultrasound was applied to enhance penetration of the particles into the skin. Visualization of the particles was revealed using a combination of luminescent spectroscopy, optical coherence tomography, confocal microscopy, and histochemical analysis. Optical clearing was used to enhance the image contrast of the luminescent signal from the particles. It was demonstrated that the penetration depth of particles depends on their size, resulting in a different detection time interval (days) of the luminescent signal from microparticles and QDs inside the rat skin in vivo. We show that luminescent signal from the upconversion microparticles and QDs was detected after the particle delivery into the rat skin in vivo during eighth and fourth days, respectively. We hypothesize that the upconversion microparticles have created a long-time depot localized in the laser-created channels, as the QDs spread over the surrounding tissues.
The meningeal lymphatic vessels were discovered 2 years ago as the drainage system involved in the mechanisms underlying the clearance of waste products from the brain. The blood–brain barrier (BBB) is a gatekeeper that strongly controls the movement of different molecules from the blood into the brain. We know the scenarios during the opening of the BBB, but there is extremely limited information on how the brain clears the substances that cross the BBB. Here, using the model of sound-induced opening of the BBB, we clearly show how the brain clears dextran after it crosses the BBB via the meningeal lymphatic vessels. We first demonstrate successful application of optical coherence tomography (OCT) for imaging of the lymphatic vessels in the meninges after opening of the BBB, which might be a new useful strategy for noninvasive analysis of lymphatic drainage in daily clinical practice. Also, we give information about the depth and size of the meningeal lymphatic vessels in mice. These new fundamental data with the applied focus on the OCT shed light on the mechanisms of brain clearance and the role of lymphatic drainage in these processes that could serve as an informative platform for a development of therapy and diagnostics of diseases associated with injuries of the BBB such as stroke, brain trauma, glioma, depression, or Alzheimer disease.
The goal of this study is to quantify the impact of the in vivo photochemical treatment of rats with obesity using indocyanine green (ICG) dissolved in saline or dispersed in an encapsulated form at NIR laser irradiation, which was monitored by tissue sampling and histochemistry. The subcutaneous injection of the ICG solution or ICG encapsulated into polyelectrolyte microcapsules, followed by diode laser irradiation (808 nm, 8 W/cm2, 1 min), resulted in substantial differences in lipolysis of subcutaneous fat. Most of the morphology alterations occurred in response to the laser irradiation if a free-ICG solution had been injected. In such conditions, membrane disruption, stretching, and even delamination in some cases were observed for a number of cells. The encapsulated ICG aroused similar morphology changes but with weakly expressed adipocyte destruction under the laser irradiation. The Cochran Q test rendered the difference between the treatment alternatives statistically significant. By this means, laser treatment using the encapsulated form of ICG seems more promising and could be used for safe layerwise laser treatment of obesity and cellulite.
To assess the effectiveness of plasmonic photothermal therapy (PPT) multiple intravenous strategy of gold nanorods (GNRs) administration was used before laser exposure. The model of alveolar liver cancer PC-1 was used in male outbred albino rats, which were intravenously administrated by single and multiple injections of GNRs and then were treated by PPT. The gold dosage was 400 μg (single injection group), 800 μg (double injection group), 1200 μg (triple injection group), and absorption maximum of gold nanorods suspension was at the wavelength of 808 nm. 24 hours after last injection the tumors were irradiated by the 808-nm diode laser during 15 min at power density 2.3 W/cm2. Temperature control of the tumor heating was provided by IR imager. 24 hours after the PPT the half of animals from each group was withdrawn from the experiments and the sampling tumor tissue for morphological study was performed. In survived animals the growth of tumors was evaluated during 21 days after the PPT. The antitumor effects of PPT after triple intravenous injection were comparable with those obtained at direct intratumoral administration of similar total dose of GNRs. The effectiveness of PPT depended on gold accumulation in tumor, probably, due to sufficient vascularization of tumor tissue.
Influence of flavonoids on the intensity of peroxidation processes in the blood is investigated by numerical modeling and by experiment in vivo. As an example we consider the effects of flavonoid-containing extract of Helichrysum arenarium L. with antitumor activity on serum of rats with transplanted liver cancer PC-1. It was found that the content of malondialdehyde, lipid hydroperoxides and average mass molecules were decreased in animals with transplanted liver cancer after intramuscular and oral administration of Helichrysum arenarium L extract in a dose of 1000 mg/mL. The extract reduces the intensity of lipid peroxidation processes in animals. The compound formation possibility of flavonoids and products of lipid peroxidation is investigated by numerical simulations. Using the density functional theory method of molecular modeling, we analyze hydrogen bonds formation and their influence on IR - spectra and structure of molecular complex which is formed due to interaction between flavonoids and products of lipid peroxidation processes on example of naringine and malondialdehyde. We have found that naringine can form a steady molecular complex with malondialdehyde by hydrogen bonds formation. Thus, the application of Helichrysum arenarium L. extract for suppression processes of lipid peroxidation and activation of enzymatic and non-enzymatic antioxidant systems is promising.
KEYWORDS: Nanoparticles, Gold, Lymphatic system, Tissues, Spleen, Bone, Plasmonics, In vivo imaging, Blood, Particles, Biomedical optics, Medical research
Currently, the usage of gold nanoparticles as photosensitizers and immunomodulators for plasmonic photothermal therapy has attracted a great attention of researches and end-users. In our work, the influence of prolonged peroral administration of gold nanoparticles (GNPs) with different sizes on the morphological changes of hematopoietic and lymphoid organs was investigated. The 24 white outbred male rats weighing 180-220 g were randomly divided into groups and administered orally for 30 days the suspension of gold nanospheres with diameters of 2, 15 and 50 nm at a dosage of 190 μg/kg of animal body weight. To prevent GNPs aggregation in a tissue and enhance biocompatibility, they were functionalized with thiolated polyethylene glycol. The withdrawal of the animals from the experiment and sampling of spleen, lymph nodes and bone marrow tissues for morphological study were performed a day after the last administration. In the spleen the boundary between the red and white pulp was not clearly differ in all experimental groups, lymphoid follicles were significantly increased in size, containing bright germinative centers represented by large blast cells. The stimulation of lymphocyte and myelocytic series of hematopoiesis was recorded at morphological study of the bone marrow. The number of immunoblasts and large lymphocytes was increased in all structural zones of lymph nodes. The more pronounced changes were found in the group with administration of 15 nm nanoparticles. Thus, the morphological changes of cellular components of hematopoietic organs have size-dependent character and indicate the activation of the migration, proliferation and differentiation of immune cells after prolonged oral administration of GNPs.
Currently, nanotechnologies are widely used in science and industry. It is known that the application of drug delivery nanostructured carriers for biomedicine is one of the promising areas of nanotechnology. Nanostructured carriers can be used in the diagnosis process for detecting a neoplastic tumor cells in peripheral blood, for contrast enhancement on magnetic resonance imaging (MRI), as well as for targeted drug delivery to tumor tissues. Agents for the targeted delivery (nanoparticles, liposomes, microcapsules, and etc) can affect the healthy tissues and organs, cause side effects and have a toxic effect. Therefore, it necessary to study the morphological changes that occur not only in the "target", such as a tumor, but also the internal organs, taking place under the influence of both the agents for targeted drug delivery and physical impact induced remote controlled drug release. Thus , the aim of our work is selection of the most promising agents for targeted drug delivery to tumor and contrast agents for in vivo visualization of tumor tissue boundaries , as well as their impact on the organs and tissues as results of nanostructured object biodistribution.
The aim of work was to study the morphological changes in transplanted liver tumors of rats after plasmonic photothermal therapy (PPTT). The gold nanorods functionalized with thiolated polyethylene glycol were injected intravenously to rats with transplanted liver cancer PC-1. A day after injection the tumors were irradiated by the infrared 808-nm diode laser. The withdrawal of the animals from the experiment and sampling of tumor tissue for morphological study were performed 24 hours after the laser exposure. The standard histological and immunohistochemical staining with antibodies to proliferation marker Ki-67 and apoptosis marker BAX were used for morphological study of transplanted tumors. The plasmonic photothermal therapy had pronounced damaging effect in rats with transplanted liver tumors expressed in degenerative and necrotic changes in the tumor cells. The decrease of proliferation marker Ki-67 and increase of expression of apoptosis marker BAX were observed in tumor cells after PPTT.
In the present work the effectiveness of antioxidants quercetine (a pure chemical) and Gratiola officinalis extract, which is obtained by a new method of extraction from plant material, is investigated on the model of photodynamic haemolysis that is a rather convenient method to monitor the rate of cell membranes oxidative destruction. The effect of these antioxidants on the rate of photodynamic haemolysis is considered as a measure of membranoprotective efficiency.
The wide application of nanotechnologies in medicine requires the careful study of various aspects of their potential safety. The effects of prolonged peroral administration of gold nanoparticles on morphological changes in lymphoid organs and indicators of peripheral blood of laboratory animals were investigated in experiment. The gold nanospheres functionalized with thiolated polyethylene glycol sizes 2, 15 and 50 nm were administered orally for 15 days to outbred white rats at a dosage of 190 μg/kg of animal body weight. The standard histological and hematological staining were used for morphological study of lymphoid organs and bone marrow smears. The size-dependent decrease of the number of neutrophils and lymphocytes was noted in the study of peripheral blood, especially pronounced after administration of gold nanoparticles with size of 50 nm. The stimulation of myelocytic germ of hematopoiesis was recorded at morphological study of the bone marrow. The signs of strengthening of the processes of differentiation and maturation of cellular elements were found in lymph nodes, which were showed as the increasing number of immunoblasts and large lymphocytes. The quantitative changes of cellular component morphology of lymphoid organs due to activation of migration, proliferation and differentiation of immune cells indicate the presence of immunostimulation effect of gold nanoparticles.
The goal of this work is to quantify impact of in vivo photochemical treatment using indocyanine green (ICG) or encapsulated ICG and NIR laser irradiation through skin of rat with obesity by the follow up tissue sampling and histochemistry. After 1 hour elapsed since 1-min light exposure samples of rat skin with subcutaneous tissue of thickness of 1.5-2.5 mm were taken by surgery from rats within marked 4-zones of the skin site. For hematoxylin-eosin histological examination of excised tissue samples, fixation was carried out by 10%-formaldehyde solution. For ICG and encapsulated ICG subcutaneous injection and subsequent 1-min diode laser irradiation with power density of 8 W/cm2, different necrotic regions with lipolysis of subcutaneous fat were observed. The obtained data can be used for safe layer-by-layer laser treatment of obesity and cellulite.
Delivery of upconversion microparticles [Y2O3:Yb, Er] and quantum dots (CuInS2/ZnS coated with PEG-based amphiphilic polymer) into rat skin using the fractional laser microablation has been studied in vivo. Luminescence spectroscopy, optical coherence tomography, confocal microscopy, and histochemical analysis were used for visualization of nanoparticles in microchannels. Results have shown that the upconversion microparticles are detected more efficiently in comparison with the quantum dots. The fluorescence intensity of the inserted upconversion microparticles is higher, when the Omnipaque™ was applied as a skin optical clearing agent. The fluorescent images of upconversion nanoparticle distribution indicate the advantage of particle delivery into skin by ultrasound.
In study the evaluation of the influence of gold nanorods on morphological indicators of red bone marrow and peripheral blood of rats with diabetes and transplanted liver tumor after intravenous administration of gold nanorods was conducted. We used gold nanorods with length 41 ± 8 nm and diameter of 10.2±2 nm, synthesized in the laboratory of nanobiotechnology IBPPM RAS (Saratov). After intravenous administration of gold nanorods the decrease of leukocytes, platelets and lymphocytes was observed in animals of control group in blood. It was marked the decrease of the number of mature cellular elements of the leukocyte germ in bone marrow - stab neutrophils and segmented leukocytes, and the increase of immature elements- metamyelocytes, indicating the activation of leukocyte germ after nanoparticle administration. The decrease of leukocyte amount was noted in blood and the increase of cellular elements of the leukocyte germ was revealed in bone marrow, indicating the activation of leukocyte germ in rats with alloxan diabetes and transplanted tumors. The changes of morphological indicators of blood and bone marrow testify about stimulation of myelocytic sprouts of hemopoiesis in bone marrow as a result of reduction of mature cells in peripheral blood after gold nanoparticle administration.
In the experiment the white outbred rats with transplanted liver cancer (cholangiocarcinoma line PC-1) and simulated alloxan diabetes were treated by single intravenous injection of gold nanorods. State of lipid peroxidation was evaluated by the following parameters: the malondialdehyde, lipid hydroperoxide, the average weght molecules in the serum of animals by conventional spectrophotometric methods study using a spectrofluorometer RF-5301 PC (Shimadzu, Japan). In both experimental groups of animals the significant increasing of levels of lipid peroxidation products was noted compared with control group. After intravenous administration of nanoparticles in the group of animals with alloxan diabetes the activation of a free radical oxidation was not observed, in group with transplanted liver cancer the increasing of levels of lipid hydroperoxide, malondialdehyde was established.
The oral administration of gold nanoparticles at dose 190 mg /kg animal body weight during 8 days leads to changes in
the cellular composition of the mesenteric lymph nodes, the severity and reversibility of the reaction was determined by
the size of gold nanoparticles. The cellular composition of the lymph nodes after the introduction of gold nanoparticle
size of 1-3 nm for 8 days corresponded the control values, indicating the absence of immunotoxicity. Duration of
recovery of cellular composition of the lymph nodes after administration of gold nanoparticles with size 15 nm and 50
nm does not exceed 21 days. It can be concluded that 15 nm and 50 nm nanoparticles have no immunotoxic action at oral
administration.
Histological slices of skin samples with the subcutaneous adipose tissue after photothermal/photodynamic treatment are analyzed. In the case of subcutaneous indocyanine green injection and 808-nm diode laser exposure of the rat skin site in vivo, the greatest changes in tissue condition were observed. Processes were characterized by dystrophy, necrosis, and desquamation of the epithelial cells, swelling and necrosis of the connective tissue, and widespread necrosis of the subcutaneous adipose tissue. The obtained data are useful for safe layer-by-layer dosimetry of laser illumination of ICG-stained adipose tissue for treatment of obesity and cellulite.
Lipid peroxidation (LP) of blood serum of laboratory animals after in vivo photodynamic treatment was investigated. To
determine changes in LP the standard colorimetric test OXYSTAT was used. The results indicate an increase in the
intensity of free radical generation in tissues induced by photodynamic treatment.
Histological slices of skin samples with the subcutaneous adipose tissue after laser irradiation at different doses are
analyzed. These data may be used at carrying out of the analysis of histological slices of skin samples with the
subcutaneous adipose tissue after photodynamic therapy. The obtained data are important for safe layer-by-layer
dosimetry of laser irradiation used in the treatment of obesity and cellulite.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.